1_2023

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100 январь—Февраль 2023 ванных составов, а также эффективность их применения. в работе [8] показано, что на ре‑ зультаты 3D‑печати наряду со свойствами используемых материалов на основе цемента оказывают большое влияние параметры са‑ мой печати. По данным [8], оптимальное от‑ ношение высоты одиночного слоя материала к диаметру сопла принтера составляет 0,4— 0,6, а наилучшие параметры работы оборудо‑ вания — объемный расход подаваемого мате‑ риала 0,09 м3/ч и скорость печати 4—8 см/с. в то же время при 3D‑печати предпочтителен возможно более короткий трубопровод для подачи смеси. в нем не должно быть колен, наличие которых может привести к останов‑ кам в работе принтера. Преобладающие способы 3D‑печати — экс‑ трузионная печать, струйная печать вяжущим, технология с использованием автоматического укладчика и сварщика арматуры (Mesh Mould) и др. в работе [4] автоматизированные адди‑ тивные технологии строительства получили дальнейшее развитие. наиболее широко ис‑ пользуется экструзионная печать (рис. 1). важнейший вопрос для 3D‑печати — вы‑ бор сырьевых материалов и состава бетонной смеси, позволяющих обеспечить ее ключевые характеристики — легкость перекачивания и экструдирования, а также последующее сохранение формы. Эти характеристики вы‑ ходят за рамки общих требований к бетон‑ ной смеси, указанных в нормах и руковод‑ ствах, — подвижности (оцениваемой по осадке конуса) и других характеристик удобоуклады‑ ваемости. Хотя итоги исследований позво‑ лили предложить некоторые эмпирические методы проектирования смесей для 3D‑пе‑ чати [9], общепринятых методов до сих пор нет. Серия экспериментов показала, что приемлемый расплыв таких смесей равен 50—60 %**; аналогичные значения приведены в работах [10—15]. на результаты определе‑ ния реологических свойств суспензий, обра‑ зуемых сыпучими материалами (в частности, материалами на основе вяжущих), влияют та‑ кие факторы, как миграция частиц и высыха‑ ние растворителя, которые также несколько ограничивают проведение реологических из‑ мерений [14—15]. в то время как для 3D‑пе‑ чати бетоном требуется материал с хорошей ** По индийскому стандарту IS: 1727—1967 расплыв определяется как увеличение среднего диаметра основания растворной массы, имеющей форму конуса, которое выра‑ жается в процентах первоначального диаметра основания, равного 100 мм (прим. ред.). цолановые вяжущие, содержащие золу-унос и микрокремнезем, могут в значительной сте‑ пени уменьшить рабочие швы и варьирование конечной прочности в смеси для 3D‑печати (возможно, благодаря меньшему объему пор и образованию более плотной микрострукту‑ ры на границе слоя). Однако такой эффект зависит и от содержания в бетонной системе влаги, необходимой для дальнейшей пуццо‑ лановой реакции с участием этих материа‑ лов [23—27]. При разработке рецептуры смеси техно‑ логия 3D‑печати накладывает ограничения на выбор некоторых параметров, напри‑ мер размеров зерен заполнителя, а также типа волокна, что дополнительно повлия‑ ет на свойства бетонной смеси. в принципе тиксотропные материалы с высоким (стати‑ ческим) предельным напряжением сдвига и с низкой вязкостью подходят для печати бетонных конструкций. Исследования по‑ казали, что количественное соотношение теста и заполнителя оказывает большое влияние на пригодность бетона для 3D‑пе‑ чати. Однако в отпечатанном образце могут наблюдаться дефекты и слабые связи между поверхностями слоев, что приводит к значи‑ тельному снижению механических характе‑ ристик отпечатанного образца по сравнению с литым бетоном, зависящему от содержания заполнителя [23—29]. в отличие от обычного монолитного бетона, имеющего плотно упа‑ кованную структуру, в бетоне, напечатанном на 3D‑принтере, должно содержаться боль‑ ше цементного теста, чтобы оно покрывало заполнители, поскольку формированием их суспензии в тесте обеспечивается возмож‑ ность экструзии. Однако слишком большое количество теста снижает способность бето‑ на сохранять форму [24—30]. Цель данного исследования — разрабо‑ тать рецептуру бетонной смеси для 3D‑пе‑ чати, оптимизировав количество материалов для ее изготовления. Для этого подбирали дозировку химических добавок в смеси, со‑ держащей также цемент, золу-унос, микро‑ кремнезем, мелкий заполнитель и воду. удобоукладываемостью, позволяющий обес‑ печить легкую транспортировку смеси (обыч‑ но путем перекачки) к печатающей головке, экструдированный материал должен быть относительно жестким, чтобы можно было гарантировать сохранение формы укладывае‑ мых слоем «нитей» [16]. Используются сопла с отверстиями различной формы — прямо‑ угольными, квадратными, круглыми и эллип‑ тическими. Форму отверстия сопла можно выбрать в соответствии с особенностями его использования. Круглые сопла обеспечивают простоту печати участков, находящихся воз‑ ле ребер и вершин конструкции или имеющих переменный угол наклона. Однако меньшая площадь контакта между порциями экстру‑ дированного материала, имеющими круглое сечение, может повлиять на стабильность слоев [17]. При 3D‑печати сохранение фор‑ мы материала после экструзии является критически важным требованием, и для его удовлетворения экструдированный материал до нанесения поверх него следующего слоя должен восстановить свою первоначальную вязкость и предельное напряжение сдвига, поскольку при деформации слоя может нару‑ шиться непрерывность конструкции [18—20]. Существует множество факторов, от кото‑ рых зависит пригодность бетона для печати. Повышение объемной доли твердой фазы (за‑ полнителей и армирующего волокна) и умень‑ шение доли цементного теста благотворно влияют на способность бетона сохранять форму, но могут ухудшить перекачиваемость и затруднить экструзию бетонной смеси для 3D‑печати. влияние объемной доли запол‑ нителей обратно влиянию доли цементного теста — ее увеличение приводит к повыше‑ нию требуемого давления при перекачивании смеси [21—22] из-за увеличения вязкости. Существенно влияет на перекачиваемость и на возможность экструзии смеси для 3D‑пе‑ чати использование крупных заполнителей. является ли конкретный максимальный раз‑ мер кусков заполнителя критическим или нет, зависит от настройки насоса и печатающей головки, а особенно от диаметра сопла. Пуц‑ Таблица 1 Физические свойства и химический состав цемента и минеральных добавок Показатель OPC 43 Зола-унос Микрокремнезем Тонина помола, м2/кг 323 334 1670 Плотность, г/см3 3,15 2,19 2,28 П.П.П., % масс. 2,30 3,64 2,73 Содержание, % масс.: SiO2 20,71 62,53 85,03 Al2O3 5,15 23,58 — CaO 59,96 1,17 — MgO 4,57 0,50 — Na2O 0,42 1,23 0,73 K2O 0,56 — 2,96 Cl– 0,012 — — нерастворимый осадок, % масс. 1,25 91,92 — рис. 1. Схема экструзионной печати [4] Экструзионное сопло Построенная часть объекта Понтонная крыша резервуара под строением Основание строения Z Y X Бетонная смесь

101 январь—Февраль 2023 и того же значения текучести, увеличивается с ростом a/b. Это связано с пониженным со‑ держанием воды в смесях с более высоким a/b. расплыв смесей, определявшийся с исполь‑ зованием встряхивающего столика согласно IS: 1727—1967, составлял 160—225 мм. При разработке состава композиций с большой объемной долей цементного теста целесообразно использовать минеральные добавки для замещения части портландце‑ мента. Пластическая вязкость повышается на 35 %, если отношение a/b увеличивает‑ ся с 0,75 до 0,9. Эту тенденцию увеличения пластической вязкости можно объяснить моделью Кригера—Догерти [21]. Также было проведено несколько испытаний с полипро‑ пиленовыми волокнами (Пв), длина и толщи‑ на которых составляли 12 мм и 40 мкм со‑ ответственно. Прочность на сжатие смесей изменялась в пределах 45—55 МПа. Можно ожидать, что если объемная доля цементного теста увеличивается за счет роста содержа‑ ния цемента или другого быстро реагирующе‑ го вяжущего, то способность бетона сохра‑ нять форму при этом улучшится. напротив, если объемная доля теста увеличивается за счет добавления инертных или медленно реагирующих добавок, то эта способность может остаться прежней, а иногда и сни‑ зиться. Что касается параметров состава смеси для 3D‑печати бетона, отметим, что выбор компонентов смеси и их пропорций зависит от особенностей применяемой тех‑ нологии 3D‑печати (рис. 2). Для обеспечения экструдируемости печатный бетон должен содержать большое количество вяжущего. Отсутствие крупного заполнителя и избыточ‑ но высокое содержание вяжущего приводят к более высокой пластичности, аутогенной усадке и усадке при высыхании и, как след‑ ствие, к большей вероятности образования трещин. Чтобы уменьшить растрескивание напечатанного на 3D‑принтере бетона, выз‑ ванное усадкой, было решено добавить в со‑ став смеси волокно. 5. Результаты и обсуждение Очевидно, что экструдируемость и способ‑ ность бетона сохранять форму зависят от раз‑ личных факторов, но для упрощения разра‑ ботки состава смеси консистенцию/текучесть пробной смеси регулировали, корректируя дозировку суперпластификатора. Было уста‑ новлено, что приготовленную бетонную смесь можно перекачивать и непрерывно выдавли‑ вать из сопла диаметром 25 мм. Печать выпол‑ няли оптимизированной бетонной смесью № 4 в 9 слоев суммарной высотой 0,225 м. Объект круглой формы, напечатанный из этого бето‑ на, оказался достаточно стабильным и сохра‑ нял свою форму ко времени печати последне‑ го слоя. Скорость печати соплом 3D‑принтера поддерживали на уровне 2 см/с. в ходе нескольких испытаний были заме‑ чены усадочные трещины в ранее напечатан‑ ных объектах с 9 слоями толщиной по 25 мм 2. Материалы в качестве основного вяжущего во всех бетонных смесях использовался коммерчески доступный обычный портландцемент (ОрС) класса 43 по IS 269 (здесь и далее указаны индийские стандарты, требованиями которых соответствовали физико-химические харак‑ теристики материалов). Золу-унос по IS 3812, ч. 1, и микрокремнезем по IS 15388 вводили в различных сочетаниях и пропорциях для приготовления двух- и трехкомпонентных бетонных смесей. Физические свойства и хи‑ мический состав этих материалов приведе‑ ны в табл. 1. Дробленый мелкий заполнитель по IS 383 относился к III группе по фракци‑ онному составу (см. табл. 9 в IS 383), размер его зерен не превышал 2,36 мм. Использовали суперпластификатор на основе поликарбок‑ силатного эфира по IS 9103 и модификатор вязкости бетонной смеси (Viscosity Modifying Admixture, VMA). 3. План эксперимента на основе результатов прошлых иссле‑ дований был подготовлен план определения свойств бетона. Из-за особенностей, связан‑ ных с различиями в назначении и характерис‑ тиках объекта, а также в процедуре его изго‑ товления, оборудование для 3D‑печати в раз‑ ных областях не может быть универсальным, но принцип его работы в целом одинаков. При разработке рецептуры бетона были приняты параметры работы 3D‑принтера, указанные в табл. 2. Осуществлялось программное ре‑ гулирование расхода впрыскиваемых жидких добавок. Диапазоны дозировки компонентов бетонной смеси, выбранные с учетом литера‑ турных данных и индивидуальных параметров 3D‑принтера, приведены в табл. 3. 4. Разработка рецептуры смеси Для оптимизации состава смеси было про‑ ведено более 30 испытаний, приготовлено 6 смесей (табл. 4) и определены их текучесть, экструдируемость, пригодность для печати и способность сохранять форму. Компоненты смешивали в смесителе с вертикальной ча‑ шей, подключенном к установке 3D‑принтера. вначале смешивали «всухую» мелкий запол‑ нитель, цемент и минеральные добавки в тече‑ ние 2 мин, после чего добавляли воду с супер‑ пластификатором. Перемешивание прекраща‑ ли через 2 мин, добавляли VMA и продолжали перемешивание в течение еще 2 мин. в результате серии пробных эксперимен‑ тов было установлено, что для печати подхо‑ дят смеси с расплывом 70—80 %. аналогич‑ ные значения расплыва бетона, пригодного для печати, приводятся в работах [19—21]. Соотношение заполнителя и вяжущего (a/b) поддерживали в диапазоне 0,75—0,90, а дози‑ ровку суперпластификатора подбирали такой, чтобы достигался расплыв 60—80 %. во все смеси вводили VMA в дозировке 0,05—0,10 % массы вяжущего. Дозировка суперпластифи‑ катора, необходимая для достижения одного каждый. в связи с этим провели эксперимен‑ ты с добавлением в бетонную смесь Пв, чтобы избежать образования трещин в 3D‑напеча‑ танных объектах и повысить стабильность последних. Объемная доля Пв в бетоне со‑ ставляла 0,1 или 0,25 % (см. табл. 4). Хотя состав смесей обеспечивал их оптимальные характеристики для дозирования и наслое‑ ния материалов, шнек в полости сопла давал сбой и забивался, если бетон содержал более 0,1 % Пв. Состав смеси с 0,1 % Пв не вызы‑ вал засорения отсека сопла. Таким образом, в качестве оптимальной приняли дозировку волокна 0,1 %, которая позволяет печатать материал без засорения сопла или образова‑ ния усадочных трещин. Проведенные ранее исследования пока‑ зали, что повышение скорости печати влияет на стабильность одиночного слоя. Дозировка суперпластификатора 0,10—0,25 % обеспе‑ чила в настоящем исследовании непрерыв‑ ную экструзию материала без засорения со‑ пла (авторы работ [10, 11] тоже предложили дозировку такой добавки выше 0,10 % для того, чтобы можно было непрерывно экстру‑ дировать материал без засорения). Ширина и толщина экструдированного слоя соответ‑ ствовали размерам сопла, т. е. тест на экс‑ трудируемость был «пройден». Измерения показали, что нижний слой напечатанной конструкции не деформируется, даже если над ним находятся 8 слоев и более (рис. 3). Однако при дальнейшем увеличении дозиров‑ ки суперпластификатора (до 0,15 %) высота нижнего слоя уменьшилась на 5 мм. При бо‑ лее низкой дозировке суперпластификатора предельное напряжение сдвига возрастало Таблица 2 Параметры работы 3D‑принтера Параметр Значение размер области печати, м 0,5—1,0 Скорость движения сопла, м/с 0,010—0,050 расход материала, м3/мин 0,050—0,100 Ширина слоя, мм 25 высота слоя, мм 10—15 Таблица 3 Пределы дозировки материалов Показатель Значение Содержание, кг/м3: вяжущего (цемента и минеральных добавок, суммарно) 800—1100 цемента OPC 43 300—600 золы-уноса 300—500 микрокремнезема 50—135 воды 250—330 Содержание химических добавок, % суммарной массы вяжущего и минеральных добавок: добавки на основе поликарбокси‑ латного эфира 0,1—0,5 VMA 0,05—0,20

102 январь—Февраль 2023 по мере повышения дозировки VMA, что позволяло экструдировать материал, тогда как расплыв не проявлял определенной тенденции изменения и варьировался в диапазоне 160—225 мм, что указывает на его зависимость от типа материала и плотности упаковки. Статическое предельное напряжение сдвига исследованных смесей — напряжение, необходимое для того, чтобы заставить течь находящийся в состоянии покоя материал (при меньшем напряжении он демонстрирует упругое поведение и не течет) — измеряли с помощью прибора Vane Shear. Значения начального напряжения сдвига печатной массы приведены в табл. 5. в результате проведенных ранее исследований влияния суперпластификаторов на вязкость [10—15] сформировалось общее мнение о том, что ввод этих добавок приводит к уменьшению предельного напряжения сдвига, однако не позволяет значительно снизить вязкость смесей на основе вяжущих материалов. Установлено, что с ростом a/b предел текучести увеличивается незначительно по сравнению с повышением пластической вязкости. высокая объемная доля теста (более 50 %) и низкая дозировка заполнителей (менее 50 %) обеспечивают лучшую перекачиваемость и экструдируемость бетонной смеси при ее постоянной подвижности. возможность экструзии материала начинала теряться в среднем через 12—15 мин после приготовления смеси, когда достигалось предельное допустимое время работы с ней. Печатать материалы после этого было сложно. Тем не менее допустимое время рарис. 2. Ограничение в параметрах проектного состава смеси для 3D­печати [31—33] 3D­печать Ограничения Максимальный диаметр зерен заполнителя высокое содержание вяжущего Проблема усадки армирование волокном боты со смесью можно регулировать, добавляя в нее суперпластификатор в подходящей дозировке. в случае образца со средним интервалом времени между печатью двух соседних слоев, равным 12—15 мин, слои были прочно скреплены между собой. Однако скрепляются только поверхности, контактирующие с воздухом, в то время как линии, разграничивающие каждый слой образца с соседними слоями, наблюдались в среднем 20 мин (для смесей № 1 и 6). По истечении 40 мин каждый слой был виден в поперечном сечении образца как отдельный объект. Пограничная линия становилась заметнее по мере увеличения интервала времени между печатью соседних слоев. Исходя из этого было установлено, что максимальный интервал при нанесении материала составляет в среднем 12 мин. Последующий слой бетона необходимо наносить поверх предыдущего через небольшой промежуток времени, чтобы материал сохранял достаточную химическую активность и пластичность для сцепления со следующим слоем. Превышение максимального «времени ожидания» перед нанесением очередного слоя может привести к образованию холодных швов. Предел текучести свежего бетона — критический параметр, определяющий стабильность формы изделия — увеличивается с течением времени при отсутствии перемешивания и других механических воздействий. Это связано с образованием зародышей C—S—H в точках контакта зерен цемента в течение индукционного периода (до начала схватывания). 5. Заключение Индивидуальный лабораторный 3D­принтер, разработанный в ходе настоящего исследования, показывает, что прототип принтера может быть полезным только для оптимизации управления подвижными частями машины, изучения свойств материалов печатаемых объектов и выбора механизма подачи материала. Однако при проектировании оборудования для промышленного применения необходимо установить взаимосвязь между скоростью вращения шнека и скоростью подачи смеси, чтобы избежать таких ситуаций, как прерывание подачи смеси и засорение сопла. Дозировка суперпластификатора, необходимая для достижения одного и того же значения текучести, увеличивалась с ростом a/b. Это связано с пониженным содержанием воды в смесях с более высоким a/b. Пластическая вязкость выросла примерно на 35 %, когда a/b увеличилось с 0,75 до 0,90. При более низкой дозировке суперпластификатора предельное напряжение сдвига росло с повышением дозировки VMA, чем обеспечивалась возможность экструдирования, тогда как расплыв смеси не проявлял определенной тенденции изменения. расплыв варьировался от 160 до 225 мм в зависимости от типа материала и плотности упаковки. Предельное напряжение сдвига смеси важно для сохраняемости формы образца — низкое значение этого показателя может привести к деформации слоев и всего изделия. Оптимальной была дозировка Пв в смеси для 3D­печати без засорения или усадочных трещин 0,1 % объема бетона. Допустимое время работы рис. 3. Объекты, напечатанные с использованием оптимизированной бетонной смеси Таблица 4 Содержание компонентов в бетонных смесях для 3D­печати номер смеси Цемент, кг/м3 Зола-унос, кг/м3 Микрокремнезем, кг/м3 Добавка на основе поликарбоксилатного эфира, % массы вяжущего VMA, % массы вяжущего вода, кг/м3 Пв, % объема бетона Мелкий заполнитель (размер зерен менее 2,36 мм), кг/м3 1 300 600 100 0,25 0,10 320 — 900 2 300 600 100 0,17 0,05 280 — 832 3 225 540 135 0,15 0,07 290 — 750 4 300 600 75 0,14 0,06 295 — 730 5 400 500 100 0,20 0,10 295 0,10 % (1,00 кг) 825 6 400 500 100 0,22 0,08 295 0,25 % (2,5 кг) 825

103 январь—Февраль 2023 со смесью составило около 12—15 мин. Све ‑ жую бетонную смесь готовили через каждые 15 мин с учетом допустимого времени работы со смесью и максимального интервала време ‑ ни между печатью соседних слоев. Исследо ‑ вания показали, что как оптимизация смеси с использованием различных комбинаций це‑ ментных вяжущих, так и выбор оптимальной дозировки суперпластификатора и VMA очень важны для получения бетона, пригодного для 3D‑печати. Бетонные смеси для 3D‑печати, внедрен ‑ ные в последние годы, содержат много це ‑ ментного вяжущего и мало заполнителей, что делает их склонными к растрескиванию при усадке и снижает их долговечность. Это не соответствует принципам устойчивого раз ‑ вития и требованию долговечности объектов. Поэтому исследование возможностей приме ‑ нения бетона для 3D‑печати с крупным за ‑ полнителем и низким содержанием вяжуще ‑ го важно для достижения цели устойчивого развития строительства. лИТераТУра 1. Khoshnevis B., Hwang D., Yao K. 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Evaluating the Influence of Aggregate Content on Pumpability of 3D Printable Concrete // RILEM Book series. 2020. P . 333—341. 23. Nerella V.N., Nather M., Iqbal A., Butler M., Mechtch ‑ erine V . Inline quantification of extrudability of cementitious ma ‑ terials for digital construction // Cement Concr. Compos. 2019. Vol. 95. P . 260—270. 24. Kruger J., Zeranka S., van Zijl G. A rheology based quasi static shape retention model for digitally fabricated concrete // Con‑ struct. Build. Mater. 2020. Vol. 254. P . 119241. 25. Ojha P.N., Mittal P., Singh A., Singh B., et al. Optimization and evaluation of ultra high performance concrete // J. of Asian Con ‑ crete Federation. 2020. Vol. 6, N 1. P . 26—36. 26. Arora V.V., Singh B. Durability studies on prestressed con ‑ crete made with Portland pozzolana cement // Indian Concrete J. 2016. Vol. 90, N 8. P . 41—48. 27. Patel V., Singh B., and Arora V.V. 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январь—февраль 2023 104 К вопросу о механизме действия интенсификаторов помола цемента УДК 666.972.162 Л.Д. Шахова1, д-р техн. наук, проф., консультант; Р.А. Котляров1, канд. техн. наук, заместитель начальника ОТСП нБн; Е.С. Черноситова2, канд. техн. наук, доцент 1 ООО «Полипласт новомосковск», россия 2 Белгородский государственный технологический университет им. в.Г. Шухова, россия РЕФЕРАТ. В статье предлагается теоретическое обоснование механизма действия технологических добавок при помоле цемента, обусловленного снятием поверхностных электростатических зарядов. Установлена взаимосвязь между поверхностной проводимостью цементных частиц и классом органических соединений. С использованием статистических методов доказано влияние типа вводящейся добавки и минералогического состава клинкера на диэлектрическое сопротивление цементных частиц и текучесть порошка. Результаты эксперимента и масштабной промышленной практики согласуются с выдвинутым предположением о возможности снятия электростатических зарядов и регулирования текучести цементного порошка с помощью технологических добавок, склонных к поляризации. Ключевые слова: интенсификаторы помола, поверхностные электростатические заряды, механизм действия, диэлектрическое сопротивление. Keywords: grinding intensifiers, surface electrostatic charges, mechanism of action, dielectric resistance. При интенсификации помола цемента в шаровых мельницах с помощью технологических добавок они воздействуют на материал в ходе измельчения и влияют на параметры процесса и свойства готового цемента. Подробная классификация технологических добавок, используемых при помоле цемента, приведена в работе [1]. в соответствии с этой классификацией применяемые добавки по функциональному назначению разделены на интенсификаторы помола (grinding aids) и добавки, позволяющие улучшить строительно-эксплуатационные свойства цемента (quality improvers). Чтобы обозначать функциональное назначение последних, было предложено использовать термин «модификаторы» по аналогии с модифицирующими добавками для бетонных и растворных смесей. нами выявлены положительная роль текучести тонкодисперсных цементных порошков в процессах их измельчения, сепарирования и транспортирования и влияние Пав на этот показатель [2]. Известно также, что текучесть тонкодисперсных порошков зависит от многих факторов, в том числе: • дисперсности порошка и формы его частиц; • минералогического состава; • электрических явлений, обусловленных электризацией частиц порошка при трении, которая вызывает прилипание частиц к металлическим поверхностям помольных агрегатов и друг к другу и отражается на эффективности помола и сепарации. Установить, от чего зависит влияние того или иного класса органических соединений, составляющих основу интенсификаторов помола, на процесс измельчения и физикомеханические свойства цемента, даже несмотря на большое число публикаций по этому вопросу, не представляется возможным ввиду использования в исследованиях, проведенных разными авторами, различных по минералогическому составу клинкеров, типоразмеров лабораторных или промышленных мельниц, их шаровой загрузки и пр. в вопросах применения технологических добавок для помола еще много неясного, а их составы находятся на стадии активных разработок. Предлагаемые в литературе механизмы действия добавок по сути описательные, т. е. это попытки воспроизвести последовательность процессов на молекулярном или коллоидном уровне, являющиеся предметом дискуссий. наиболее распространена теория ребиндера, объясняющая действие Пав при измельчении более легким деформированием и разрушением твердых тел и самопроизвольным протеканием в них структурных изменений в результате уменьшения их свободной поверхностной энергии при конНовокузнецк ОХРАНА, БЕЗОПАСНОСТЬ ТРУДА И ЖИЗНЕДЕЯТЕЛЬНОСТИ НЕДРА РОССИИ 6-9 июня 2023 XIII Международная специализированная выставка VIII Международная специализированная выставка XXXI Международная специализированная выставка технологий горных разработок II Специализированная выставка ПРОМТЕХЭКСПО

Новокузнецк ОХРАНА, БЕЗОПАСНОСТЬ ТРУДА И ЖИЗНЕДЕЯТЕЛЬНОСТИ НЕДРА РОССИИ 6-9 июня 2023 XIII Международная специализированная выставка VIII Международная специализированная выставка XXXI Международная специализированная выставка технологий горных разработок II Специализированная выставка ПРОМТЕХЭКСПО реклама

январь—февраль 2023 106 такте со средой, содержащей вещества, способные к адсорбции на межфазной поверхности. Однако в последние годы эта теория опровергнута ввиду появления новых данных. на практике уменьшение критического напряжения наблюдается только при более низких скоростях распространения трещин [3]. результаты моделирования показали, что скорость распространения трещины в кристалле клинкерного минерала С3S вдоль поверхности спайности достигает в ходе измельчения 11 500 км/ч, что почти в 10 раз больше скорости звука в воздухе [4, 5]. Скорость диффундирования молекул Пав на твердой поверхности разлома клинкерных кристаллов значительно ниже — от 1 мкм/c до 10 м/с (36 км/ч), в зависимости от условий [6]. Таким образом, скорость перемещения молекул Пав по свежей поверхности излома несоизмерима со скоростью распространения трещин, что исключает их способность уменьшить работу разрушения кристалла. Для объяснения роли Пав, входящих в состав интенсифицирующих добавок при помоле, в зарубежной литературе выдвинута теория нейтрализации статических зарядов на поверхности твердых частиц в присутствии молекул органических веществ [7, 8]. единственное подтверждение действия Пав как антистатика — результаты исследований, выполненных сотрудниками Цементной ассоциации СШа (Portland Cement Association USA), в ходе которых они измеряли электростатические заряды при помоле в шаровой мельнице с помощью электростатического измерителя поля ETS (модель 222 со специально изготовленным индикаторным зондом) [9]. результаты показали, что при помоле без интенсификатора цемент в разгрузочном патрубке имел электрический потенциал на порядок выше, чем при входе в мельницу. При подаче интенсификатора потенциал снижался и знак заряда изменялся на отрицательный. Возникновение статических зарядов на поверхности цементных частиц возникновение зарядов на поверхности частиц твердых тел можно объяснить двумя причинами. 1. Измельчение твердой частицы включает в себя образование и распространение трещин под действием напряжений, создаваемых внешними силами. Критическое напряжение распространения трещины определяется по уравнению Гриффитса [10] на основе значений модуля Юнга, поверхностной энергии и длины трещины. При тонком измельчении разность плотности зарядов на противоположных стенках трещины, возникающей при воздействии мелющих тел на материал, может достигать десятков единиц CGSE на 1 см2 (до 1010 элементарных зарядов на 1 см2) [11]. совпадает с полярностью переносящего носителя заряда, и в случае переноса положительного заряда самая большая частица будет заряжена положительно, а самая маленькая частица — отрицательно, и наоборот [20]. Электростатическая адгезия Электростатические заряды, возникающие на поверхности твердых частиц при трении, обусловливают притяжение частиц и их агрегацию в более крупные конгломераты [21]. в основе электрической теории адгезии лежит представление о двойном электрическом слое, образующемся при тесном контакте двух поверхностей. При разделении частиц возникает разность электрических потенциалов, которая повышается с увеличением зазора между раздвигаемыми поверхностями до определенного предела, когда наступает разрыв. Таким образом, на границе раздела адгезия—прилипание образуется электростатическая сила, обусловленная наличием двойного электрического слоя. Эти силы объясняют сопротивление разделению [22]. Сила адгезии F в результате электростатического взаимодействия при высокой плотности электризации выражается уравнением по модели плоского конденсатора [22]: 2 0 2 0 ( U ) F , 2H 2 ε ρ = = ε (2) где U — разность потенциалов, ε0 — диэлектрическая проницаемость, ρ — поверхностная плотность заряда, н — расстояние между взаимодействующими поверхностями. Роль электризации в процессе измельчения в условиях электростатики, т. е. когда электрические заряды неподвижны, напряженность электрического поля внутри частицы всегда равна нулю. Поэтому заряженные однократно частицы диэлектриков сохраняют свой заряд в течение нескольких часов, даже если частицы материала располагаются на заземленной металлической поверхности (мельницы, силоса). При измельчении твердых материалов электризация играет негативную роль, противодействуя достижению высокой размалываемости материалов за счет агрегирования тонких частиц и налипанию их на мелющие тела и футеровку мельницы. в ходе сепарации агрегаты частиц воспринимаются как крупные частицы и возвращаются в первую камеру мельницы, при этом повышаются затраты электроэнергии на повторное разрушение агрегированных частиц. возвращенные мелкие частицы в первой камере выполняют роль «подушки», что снижает эффективность работы мелющих тел. Снижается скорость прохождения потока материала сквозь мельницу. При хранении порошков электризация способствует зависанию часЗаряд частицы после разделения поверхностей определяется выражением [12]: Qч = σσSк – Qос – Qн, (1) где σσ — плотность электрического заряда двойного слоя, Кл/м2; Sк — площадь поверхности контакта, м2; Qос — заряд, стекающий через омическое сопротивление контактирующих поверхностей; Qн — заряд, нейтрализованный в результате ионных процессов, протекающих в зазоре между разделяющимися поверхностями. Таким образом, заряды будут оставаться на поверхностях после их разделения при условии, что время разделения контакта меньше времени релаксации зарядов. При отрыве поверхностей друг от друга обнаруживаются частицы с зарядом обоих знаков. При этом знак заряда не зависит от знака начального заряда частиц, а значение заряда в десятки раз превышает первоначальные заряды, фиксируемые после осаждения частиц на поверхности. 2. Статическое электричество накапливается при трении. во второй камере мельницы измельчение происходит за счет истирающих воздействий. При трении повышается площадь поверхности контакта между двумя материалами и интенсифицируется перенос одного материала на другой, что способствует накоплению зарядов на поверхности частиц. напряженность электрического поля при электризации путем трения зависит от физико-химического состояния частиц, площади и формы ее поверхности и скорости движения относительно среды. Превалируют отрицательно заряженные частицы, доля которых составляет примерно 75 % их общего числа [13—17]. Детальные исследования размеров частиц показали, что заряд непрерывно увеличивается с уменьшением размера частиц. Установлено, что при размере частиц 330—500 мкм заряд составлял 10 нКл на 1 г, тогда как при их размере 90—120 мкм — 65 нКл на 1 г [18]. авторы посчитали, что возможной причиной различия является адгезия мелких частиц (размером менее 40 мкм) к крупным частицам, которые в конечном счете повышают шероховатость поверхности крупных частиц, аналогично эффектам рисунка/микроструктуры. авторы работы [19] доказали, что простые геометрические факторы приводят к нетто-переносу электронов от более крупных частиц к более мелким. Основываясь на модели контактного переноса заряда между двумя частицами, авторы работы [20] установили, что для системы гранулированных частиц различных размеров из-за их множественных столкновений существует пороговый радиус частиц — имеющие бóльший и меньший радиусы несут противоположные заряды. Пороговый радиус частиц равен среднему их размеру в такой системе. в принципе полярность зарядов, переносимых на самую большую частицу,

ßÍÂÀÐÜ—ÔÅÂÐÀËÜ 2023 107 òèö â åìêîñòÿõ õðàíåíèÿ; ïðè òðàíñïîðòèðîâàíèè, îñîáåííî ñ âûñîêèìè ñêîðîñòÿìè ïîòîêîâ, ìàòåðèàë íàëèïàåò íà ñòåíêè òðóáîïðîâîäîâ è ðàáî÷èå ýëåìåíòû íàñîñîâ. Âñå ýòî ñîçäàåò îïðåäåëåííûå òðóäíîñòè ïðè ðàáîòå ñ òîíêîäèñïåðñ íûìè ìèíåðàëüíûìè ïîðîøêàìè. Ñíÿòèå ýëåêòðîñòàòè÷åñêèõ çàðÿäîâ îðãàíè÷åñêèìè äîáàâêàìè Ñîãëàñíî óðàâíåíèþ (2), óìåíüøèòü ñèëó àäãåçèè ìîæíî, ñíèæàÿ ðàçíîñòè ïîòåíöèàëîâ ìåæäó äâóìÿ ÷àñòèöàìè; èçìåíÿÿ ïîâåðõíîñòíóþ ïëîòíîñòü çàðÿäà; óâåëè÷èâàÿ ðàññòîÿíèå ìåæäó âçàèìîäåéñòâóþùèìè ïîâåðõ íîñòÿìè. Íè ó êîãî íå âûçûâàåò ñîìíåíèÿ, ÷òî ìåõàíèçì äåéñòâèÿ îðãàíè÷åñêèõ äîáàâîê îñíîâàí íà ïðîöåññàõ àäñîðáöèè íà ñâåæåñôîðìèðîâàííîé ïîâåðõíîñòè ïðè èçìåëü÷åíèè ÷àñòèö. Äëÿ âûáîðà âèäà ÏÀÂ, âõîäÿùåãî â ñîñòàâ èíòåíñèôèêàòîðà ïîìîëà, íåîáõîäèìî ïîíèìàòü ìåõàíèçì ðàáîòû ìîëåêóëû îðãàíè÷åñêîãî âåùåñòâà ïîñëå àäñîðáöèè íà ïîâåðõíîñòè òâåðäûõ ÷àñòèö ïðè èçìåëü÷åíèè.  êà÷åñòâå ðàáî÷åé ãèïîòåçû î ìåõàíèçìå ðàáîòû òàêèõ ìîëåêóë íà ïîâåðõíîñòè öåìåíòíûõ ÷àñòèö áûëà ïðèíÿòà òåîðèÿ íåéòðàëèçàöèè ñòàòè÷åñêèõ çàðÿäîâ ìîëåêóëàìè ÏÀ [7, 8]. Êðîìå òîãî, ìîëåêóëû îðãàíè÷åñêèõ âåùåñòâ ñîçäàþò ñòåðè÷åñêèé ýôôåêò îòòàëêèâàíèÿ, ÷òî â ñâîþ î÷åðåäü ñíèæàåò àãëîìåðàöèþ òîíêîäèñïåðñíûõ ÷àñòèö â õîäå èçìåëü÷åíèÿ.  ðàáîòàõ [24, 25] ïðèâåäåíû ðåçóëüòàòû ìîëåêóëÿðíîãî ìàòåìàòè÷åñêîãî ìîäåëèðîâàíèÿ ïðîöåññîâ àäñîðáöèè íà ïîâåðõíîñòÿõ ðàñêîëà êðèñòàëëîâ, ïîäòâåðæäàþùèå èçìåíåíèå àãëîìåðàöèè â ïðèñóòñòâèè ðÿäà îðãàíè÷åñêèõ ñîåäèíåíèé. Áûëî ïîäòâåðæäåíî, ÷òî ãëàâíûé ýôôåêò äåéñòâèÿ èíòåíñèôèêàòîðîâ çàêëþ÷àåòñÿ â ñíèæåíèè ýíåðãèè àãëîìåðàöèè çà ñ÷åò óìåíüøåíèÿ ïîâåðõíîñòíîé ïîëÿðíîñòè. Ïàðàëëåëüíî ñ ïîñëåäíåé óìåíüøàåòñÿ ïîâåðõíîñòíàÿ ýíåðãèÿ. Ýíåðãèÿ àãëîìåðàöèè èìååò îáðàòíóþ êîððåëÿöèþ ñ ïðîèçâîäèòåëüíîñòüþ ïîìîëà. ×åì áîëüøå ñíèæàþòñÿ êóëîíîâñêèå ñèëû ïðèòÿæåíèÿ ìåæäó äâóìÿ ïîâåðõíîñòÿìè, òåì ìåíüøå ñèëà àãëîìåðàöèè è áîëåå ýôôåêòèâåí ïîìîë. Äðóãàÿ ïðè÷èíà ñíèæåíèÿ àãëîìåðàöèîííûõ ñèë ìåæäó ðàñêîëîòûìè ïîâåðõíîñòÿìè êëèíêåðíûõ ìèíåðàëîâ, ïî ìíåíèþ àâòîðîâ ðàáîò [24, 25], — íà÷àëüíàÿ ãèä ðàòàöèÿ íà ïîâåðõíîñòè. Ãèäðàòèðîâàííûå ïîâåðõíîñòè èìåþò áîëåå íèçêóþ ïîëÿðíîñòü, íàïðèìåð, èç-çà ãðóïï Al—OH âìåñòî ïîëó èîííûõ ñâÿçåé Àl—Î, è êóëîíîâñêèå ñèëû âçàèìîäåéñòâèÿ â ðåçóëüòàòå îñëàáëÿþòñÿ. Òàêîé ýôôåêò îòìå÷àåòñÿ ïðè âïðûñêèâàíèè âîäû âî âòîðóþ êàìåðó ìåëüíèöû. Îäíîâðåìåííî ñëåäóåò ó÷èòûâàòü, ÷òî èçìåëü÷àåìûå ÷àñòèöû èìåþò øåðîõîâàòîñòü, óãëóáëåíèÿ è òðåùèíû, êîòîðûå ñîçäàþò àêòèâíîå ñîïðîòèâëåíèå ïðè äâèæåíèè ñëîåâ ïîðîøêà. Âëèÿíèå àáðàçèâíîãî ýôôåêòà ìåëêèõ ÷àñòèö ìîæåò áûòü ñíèæåíî «ñìàçî÷íûì» ýôôåêòîì óãëåâîäîðîäíûõ ðàäèêàëîâ àäñîðáèðîâàííîé äîáàâêè, íàïðàâëåííûõ âî âíåøíþþ ñðåäó. Ïðè ýòîì î÷åíü ñèëüíî óâåëè÷èâàåòñÿ ïîðîøêîâàÿ òåêó÷åñòü. Ðàñ÷åòíûé ìèíåðàëîãè÷åñêèé ñîñòàâ èññëåäóåìûõ êëèíêåðîâ Çàâîä-èçãîòîâèòåëü Èíäåêñ êëèíêåðà Ñîäåðæàíèå ìèíåðàëîâ, % ìàññ. Ìîäóëüíàÿ õàðàêòåðèñòèêà C3S C2S C3A C4AF ÊÍ n p ÎÎÎ «Õîëñèì (Ðóñ) Ñòðîèòåëüíûå ìàòåðèàëû» Ê1 70,5 10,9 17,2 1,4 0,92 3,26 14,57 ÇÀÎ «Îñêîëöåìåíò» Ê2 61,7 16,6 9,5 12,2 0,93 1,92 0,86 ÇÀÎ «Áåëãîðîäñêèé öåìåíò» Ê3 62,3 17,4 7,4 12,9 0,90 2,17 1,34 ÇÀÎ «Êàâêàçöåìåíò» Ê4 64,4 12,8 3,2 19,6 0,94 1,90 0,90 Óâàæàåìûå ÷èòàòåëè! Вы можете подписаться на наш журнал, начиная с любого номера. Äëÿ îôîðìëåíèÿ ïîäïèñêè ïðèøëèòå, ïîæàëóéñòà, ïî ýëåêòðîííîé ïî÷òå çàÿâêó, óêàçàâ â íåé: ïîëíîå íàèìåíîâàíèå Âàøåé êîìïàíèè; ÷èñëî ýêçåìïëÿðîâ æóðíàëà è ñðîê ïîäïèñêè; ýëåêòðîííûé èëè ïî÷òîâûé àäðåñ äëÿ îòïðàâêè äîãîâîðà íà ïîäïèñêó; íîìåð êîíòàêòíîãî òåëåôîíà. +7 (812) 242-1124 E-mail: [email protected] www.jcement.ru Âû ìîæåòå òàêæå ïðèñëàòü çàÿâêó íà ïðèîáðåòåíèå ðàíåå âûøåäøèõ íîìåðîâ æóðíàëà. 4-2009 ISSN 1607-8837 4 -2009 ISSN 1607-8837 ÖÅÌÅÍÒ È ÅÃÎ ÏÐÈÌÅÍÅÍÈÅ ¹3-2016 3-2016 ISSN 1607-8837 ĴńŕŜŌŔŠŖʼnŕņŒŌ ņŒŋŐŒŊőŒŕŖŌ œŔŌŐŌőŌŐńŏŠőŒō œŏŒŝńňŌ ŋńŕŖŔŒōŎŌ ĦŎŒŐœńőŌŌ2/+Őş ŖņʼnŔňŒņʼnŔŌŐśŖŒŏŌňʼnŔŕŖņŒ ŒŋőńśńʼnŖœŔŒŔşņœŔŌņŒňţŝŌō ŎŌŋŐʼnőʼnőŌŢŔşőŎń ŁŖŒŎńŎőʼnŏŠŋţŏŗśŜʼnņŌňőŒ őńœŔŌŐʼnŔʼnőńŜʼnō ŕŌŕŖʼnŐşCOMFLEX® ķŋőńōŖʼnŅŒŏŠŜʼnŒŖŒŐśŖŒ2/+ŐŒŊʼnŖŕňʼnŏńŖŠňŏţ ĦńŜʼnŇŒœŔʼnňœŔŌţŖŌţ őńŕńōŖʼn^^^ROKJVT

январь—февраль 2023 108 необходимая дозировка органического соединения пропорциональна тонкости помола цемента. наши расчеты показали, что для молекул триэтаноламина (ТЭа) посадочная площадь равна 36,5 · 10—16 см2. При дозировке ТЭа в мельницу при помоле 150 г на 1 т цемента покрытие поверхности частиц цемента с удельной площадью 300 м2/кг составляет 60—70 %. Для покрытия 50 % свободной поверхности цементных частиц молекулами глицерина требуется внести его в количестве от 150 до 250 г/т цемента с удельной поверхностью 300 и 500 м2/кг соответственно. Практически за короткое время пребывания материала в мелющей системе (6—30 мин) должны пройти адсорбционные процессы, в результате которых молекулами Пав будет покрыто 50— 70 % вновь созданной поверхности материала. Обоснование методики эксперимента Для обнаружения эффекта снятия электростатического заряда с поверхности была выдвинута гипотеза об изменении электропроводимости диэлектрических цементных частиц при нанесении на их поверхность органических веществ с молекулами, склонными к поляризации в соответствии с формулой Клаузиуса—Моссотти [1]. Как нам представляется, механизм повышения поверхностной проводимости цементных частиц связан со способностью молекул таких веществ к поляризации под действием локальных силовых полей на свежесколотых поверхностях и снятием остаточных электростатических зарядов из-за роста электропроводимости при поляризации. Количество свободных электронов в диэлектриках мало, и поэтому проводимость их тоже мала (10—8…10—18 См/см). Проводимость может возникать в диэлектриках по двум причинам: вследствие смещения зарядов, которые возникают при различной поляризации (абсорбционных токов) и вследствие перемещения (примесных) ионов. если к цементным частицам приложить постоянное напряжение и при этом измерять протекающий через них ток, то можно получить зависимость тока утечки iут от времени приложения напряжения. Ток утечки представляет собой сумму двух токов [26]: iyт = iабс + iск, (3) где iабс — ток абсорбции, iск — сквозной ток, или ток сквозной проводимости. рис. 1. результаты расчета в модуле ANOVA в программе Statistica. SS — сумма квадратов значений (используется для вычисления внутригрупповой дисперсии), MS — средний квадрат значений (отношение SS к числу степеней свободы), F — расчетное значение критерия фишера, р — расчетный уровень значимости рис. 2. влияние технологических добавок и минералогического состава клинкеров на текучесть цементных порошков лабораторного помола; б/д — без добавки рис. 4. взаимосвязь между сопротивлением и текучестью цементов с интенсификаторами помола (а) и без добавок (б) рис. 3. влияние технологических добавок и минералогического состава клинкеров на диэлектрическое сопротивление образцов из цементного порошка; б/д — без добавки 2800 2600 2400 2200 2000 1800 1600 1400 1200 Сопротивление, МОм б/д ЭГ ПЭГ ТЭа типа литопласт аи литопласт иП1 литопласт иМ1 Клинкер Добавка К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 а бСопротивление, МОм Сопротивление, МОм Текучесть Текучесть 2300 2300 2400 2500 2600 2200 2200 2100 2100 2000 2000 1900 1800 1700 1600 1500 1400 38 40 33 Текучесть:Сопротивление, МОм: у = 3023,8535 – 25,262х r = –0,8838; p = 0,0000; r2 = 0,7812 Сопротивление, МОм: у = 3023,8535 – 25,262х; доверительный интервал 0,95 Сопротивление, МОм: y = 4102,0768 – 49,8228х; доверительный интервал 0,95 Текучесть:Сопротивление, МОм: y = 4102,0768 – 49,8228х r = –0,7802; p = 0,0028; r2 = 0,6087 42 44 46 48 50 52 54 56 58 60 34 35 36 37 38 39 40 41 42 60 56 52 48 44 40 36 Текучесть, % б/д ЭГ ПЭГ ТЭа типа литопласт аи литопласт иП1 литопласт иМ1 Клинкер Добавка К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 60 56 52 48 44 40 36 Текучесть, % б/д ЭГ ПЭГ ТЭа типа литопласт аи литопласт иП1 литопласт иМ1 Клинкер Добавка К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 60 56 52 48 44 40 36 Текучесть, % б/д ЭГ ПЭГ ТЭа типа литопласт аи литопласт иП1 литопласт иМ1 Клинкер Добавка К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4 К1 К2 К3 К4

январь—февраль 2023 109 Ток абсорбции обусловлен быстрыми поляризационными процессами, происходящими с момента приложения напряжения. Сквозной ток зависит от диэлектрических свойств цементных частиц. Таким образом, можно определить ток адсорбции при нанесении на поверхность различных веществ. Электрическая проводимость диэлектрических материалов зависит от влажности, температуры окружающей среды и наличия на их поверхности адсорбированных молекул органических веществ. Электрическая проводимость обратно пропорциональна диэлектрическому сопротивлению. Достаточно тончайшего слоя адсорбированных молекул на поверхности диэлектрика, чтобы была обнаружена заметная проводимость, определяемая в основном толщиной этого слоя. Удельное поверхностное сопротивление тем выше, чем меньше полярность адсорбированного на поверхности вещества. Снятие электростатических зарядов должно привести к уменьшению поверхностных сил притяжения, вызванных электростатической составляющей адгезии, и за счет этого — к снижению агломерации мелких частиц и повышению текучести цементного порошка. Электростатическое взаимодействие и текучесть зависят от ряда факторов. вызывало интерес влияние минералогического состава цементного клинкера и класса органических соединений на эти характеристики. Цель работы заключалась в обнаружении эффекта снятия электростатических зарядов молекулами органических соединений, склонных к поляризации, установлении взаимосвязи между диэлектрическим сопротивлением цементных порошков и их текучестью и определении влияния на эти показатели минералогического состава клинкеров. Методы и материалы Для подтверждения влияния на электропроводимость (диэлектрическое сопротивление) органических соединений исследовали пробы цемента, полученные в результате помола в лабораторной мельнице промышленных клинкеров различного минералогического состава совместно с гипсом в присутствии соединений классов гликолей и аминов — этиленгликоля (ЭГ), полиэтиленгликоля (ПЭГ), ТЭа и триизопропаноламина (ТИПа), а также комплексных составов интенсификаторов помола производства ООО «Полипласт новомосковск», таких как «литопласт аИ», «литопласт ИП» и «литопласт ИМ». Технологические добавки вводили в мельницу вместе с компонентами цемента в дозировке 0,2 % массы цемента. Минералогический состав клинкеров приведен в таблице. на основе клинкеров К2 и К3 выпускаются цементы общестроительного назначения, на основе клинкера К4 изготавливают сульфатостойкие цементы, К1 — клинкер для белого цемента. Цементные порошки лабораторного помола имели примерно равную удельную поверхность по Блейну 300 ± 10 м2/кг. Текучесть порошков определяли по методике ASTM С1565—09 по массе порошка, прошедшего сквозь сито № 05 при механическом воздействии. Для определения диэлектрического сопротивления из цементных порошков прессовали цилиндры размерами D = H = 20 мм. Сопротивление образцов протеканию тока измеряли прибором «Измеритель сопротивления изоляции 1800 IN/1801 IN/1832 IN/1851 IN». Принцип действия прибора основан на измерении падения напряжения на сопротивлении изоляции под действием тока, возникающего при приложении испытательного высокого напряжения с последующим преобразованием в пропорциональное значение сопротивления. Испытательное напряжение постоянного тока не превышало 2500 в, тестовый ток — 2 ма, погрешность измерения составляла ±5 % предельного значения измеряемых величин. Сопротивление изоляции измерялось в мегаомах. Для каждого цемента диэлектрическое сопротивление и текучесть измеряли на трех образцах. Для изучения взаимосвязей диэлектрического сопротивления, минералогического состава цемента и текучести цементного порошка АО ПОдОльск Цемент производит и реализует оптом и в розницу Телефон/факс: +7 (495) 502-79-34 (35), +7 (4927) 65-09-02, +7 (929) 554-25-15 [email protected] www.podolsk-cement.ru реклама Напрягающий цемент НЦ-20-32,5 Н Сульфатостойкий портландцемент ЦЕМ I 42,5 Н СС Высокоглиноземистое вяжущее ВГВ-М-60-1-50, ВГЦ-II Глиноземистое вяжущее ГВ-40, ГВ-50, ГВ-60 Сульфоалюминатнобелитовый цемент САБЦ-30-1 Смесь безусадочная быстротвердеющая ремонтная ССБВР Смесь гидроизоляционная М600 и М700

январь—февраль 2023 110 применили методы корреляционно–регрессионного и дисперсионного анализа, реализованные в программе Statistica. Результаты и обсуждение все цементные порошки исследовали на текучесть по методу ASTM С1565-09, суть которого заключается в определении способности порошка протекать сквозь сито с размером ячеек 500 мкм. После этого из порошкообразных бездобавочного цемента и цементов с технологическими добавками спрессовали по три образца, на которых определяли диэлектрическое сопротивление. на первом этапе статистического исследования провели формальный статистический тест для проверки гипотезы о том, что обнаруженная связь между исследуемыми факторами носит случайный характер, а не является свойством совокупности. Для этого использовали уровень значимости р — количественную оценку надежности связи: чем меньше его значение, тем выше статистическая значимость результатов исследования, подтверждающего указанную гипотезу. Дисперсионный анализ полученных данных в модуле ANOVA (Analysis of Variation) продемонстрировал значимость различий между средними значениями сопротивления и текучести цементных порошков, полученных на клинкерах с разным минералогическим составом (эффект — «Клинкер») в присутствии различных технологических добавок (эффект — «Добавка») (рис. 1). Поскольку расчетное значение р оказалось для всех исследованных факторов («Добавка», «Клинкер», совместное влияние «Добавки» и «Клинкера») меньше 0,05, принятого в качестве граничного значения для проверки гипотезы, был сделан вывод о статистической значимости полученных данных о влиянии «Добавки» на сопротивление прессованных образцов из цемента и на текучесть цементных порошков. Таким образом, средние значения текучести и сопротивления для добавочных и бездобавочных смесей значимо различаются. Для графического представления влияния «Клинкера» и «Добавки» на текучесть и диэлектрическое сопротивление цементных порошков в программе Statistica были построены графики изменчивости (рис. 2 и 3). в присутствии гликолей (ЭГ и ПЭГ) текучесть повысилась на 20—22 %, а при добавлении ТЭа и ТИПа — на 20—32 и 40—52 % соответственно (см. рис. 2). При вводе каждой из добавок текучесть варьировалась в пределах 2—6 % в зависимости от минералогического состава клинкеров. результаты экспериментов показали, что выбранные для исследования добавки снижают диэлектрическое сопротивление порошка цемента на 13—40 %. наименьшее влияние на снятие статических зарядов оказывают гликоли (ЭГ и ПЭГ), наибольшее — амины (ТЭа и ТИПа). в цементах без интенсификаторов помола сильнее выражено влияние минералогического состава на сопротивление (см. рис. 3). введение интенсифицирующих добавок нивелирует влияние минералогического состава на сопротивление (см. рис. 3), и в результате изменяется текучесть цементного порошка (см. рис. 2). Отметим, что промышленные образцы интенсификаторов помола содержат комплекс химических реагентов, проявляющих синергетический эффект по снижению сопротивления. Так, при вводе добавки «литопласт ИМ1» сопротивление понизилось в зависимости от вида клинкера на 26—34 %, а текучесть повысилась на 40—57 %. Также отмечаются незначительные колебания диэлектрического сопротивления при вводе определенной добавки для клинкеров с разным минералогическим составом (в пределах 10—12 %). Колебания коэффициента парной корреляции для минералогического состава (попеременно варьировалось содержание C3S, C2S, C3A и C4AF) и диэлектрического сопротивления цемента с каждой из исследуемых добавок составляли ±0,24, что свидетельствует о незначительной взаимосвязи этих переменных. Цемент К1 во всех случаях — и с добавкой, и без нее — имеет более высокое сопротивление, за исключением образца с добавкой «литопласт аИ», для которого, наоборот, сопротивление минимально. рассчитанные значения коэффициента регрессии показали интенсивное влияние сопротивления на текучесть цементного порошка. Была установлена обратная линейная корреляция между сопротивлением и текучестью порошка (рис. 4). на диаграммах рассеяния, полученных в программе Statistica, дополнительно приведены уравнения линейной регрессии y = f(x), а также значения p и коэффициентов корреляции r (см. рис. 4). Представленные зависимости аппроксимированы к линейной модели. Сила связи между сопротивлением и текучестью по шкале Чеддока высокая, при этом коэффициент корреляции для цементов с добавками больше (r = –0,8838), чем для бездобавочных цементов (r = –0,7802). Приведенные на рис. 4 расчетные коэффициенты детерминации r2 (0,7812 для цементов с добавками и 0,6087 — без добавок) показывают, что при вводе добавок диэлектрическое сопротивление образцов из цемента сильнее влияет на текучесть порошка. Таким образом, статистический анализ полученных результатов показал, что введение интенсифицирующей добавки при помоле снижает сопротивление изоляции цементных частиц с бездобавочными составами, что подтверждает выдвинутую гипотезу об изменении поверхностного заряда частиц адсорбированными молекулами органических соединений, входящих в состав интенсификаторов. анализ результатов экспериментов, проведенных в настоящей работе, еще раз подтвердил полученные в течение многих лет при промышленном внедрении интенсификаторов помола на цементных предприятиях данные о влиянии добавок на повышение текучести цементного порошка (см. рис. 2) [27]. Полученные результаты легли в основу правила подбора компонентов комплексных технологических добавок, которые разрабатываются с учетом минералогического состава клинкера. При выборе Пав как компонента интенсификатора учитываются молекулярная структура и поверхностная активность органического соединения, а также наличие неподеленной пары электронов, которые могут взаимодействовать с ионами металлов измельчаемого материала с образованием донорно-акцепторных комплексов [1]. Эти характеристики должны определять высокую скорость диффундирования молекул к месту нахождения разорванных валентных связей кристаллических соединений и изменение значений поверхностных зарядов за счет поляризации молекул после их адсорбции на поверхности твердых частиц. Показатель текучести цементного порошка при подборе рецептуры промышленных составов интенсификаторов помола был принят в качестве критерия оценки эффективности: чем выше показатель текучести, тем эффективнее работает добавка в качестве интенсификатора помола. рабочая методика определения текучести цементных порошков при вводе интенсификатора была внедрена сотрудниками ООО «Полипласт новомосковск» на многих цементных предприятиях для текущего контроля работы добавки и режима работы помольной установки, включая сепарирование. Выводы Данные о диэлектрическом сопротивлении прессованных образцов из цементного порошка подтвердили выдвинутую гипотезу о снятии электростатических зарядов с поверхности частиц адсорбированными молекулами органических соединений, склонных к поляризации, и о снижении агломерации частиц в ходе помола. Статистическими методами установлена обратная зависимость между диэлектрическим сопротивлением и текучестью цементного порошка, обусловленная меньшими электростатическими силами притяжения между частицами для составов с более высоким сопротивлением. Подтверждена зависимость диэлектрического сопротивления от минералогического состава в отсутствие технологических добавок. ввод добавок, особенно группы аминов, при помоле нивелирует влияние минералогического состава на диэлектрическое со-

январь—февраль 2023 111 противление и, соответственно, на текучесть цемента. Текучесть цементного порошка является косвенным критерием оценки эффективности работы интенсификатора помола в промышленных условиях. Учет склонности к поляризации молекул органических веществ при разработке промышленных рецептур интенсификаторов помола позволяет достичь синергетического эффекта действия технологических добавок на повышение текучести цемента и, следовательно, на эффективность измельчения. лИТераТУра 1. Шахова л.Д., Черкасов р.а., Манелюк Д.Б., Березина н.М. Классификация технологических добавок при помоле цемента // фундаментальные исследования. 2014. № 12. С. 295—299. 2. Шахова л.Д., Черноситова е.С., Щелокова л.С., Уханева н.Г. Структурно-реологические свойства цементного порошка // Цемент и его применение. 2022. № 1. С. 102—105. 3. латышев О.Г., Жилин а.С., Осипов И.С., Сынбулатов в.в. выбор поверхностно-активной среды для управления свойствами пород в горной технологии // Изв. вузов. Горный журнал. 2004. № 6. С. 117—121. 4. Weibel M., Mishra R.K. Comprehensive understanding of grinding aids // ZKG International. 2014 [Электронный ресурс]. Учредитель: ООО «ПЕТРОЦЕМ». Свидетельство о регистрации ПИ № ФС77-69313 от 06 апреля 2017 г. Федеральная служба по надзору в сфере связи, информационных технологий и массовых коммуникаций (Роскомнадзор) Адрес редакции: 191119, Санкт-Петербург, ул. Звенигородская, д. 22, лит. А, пом. №440 №442. Тел. +7 (812) 242-11-24. Сдано в набор 10.03.2023. Подписано к печати 30.03.2023. Формат 60.901/8. Бум. офсет. усл. печ. л. 10,75. Кр.-отт. 4,0 Уч. изд. л. 10.75. Тираж 2000 экз. Цена в розницу свободная. Требования к материалам, направляемым в журнал «Цемент и его применение» для опубликования Журнал «Цемент и его применение» принимает для публикации материалы, отражающие состояние и развитие цементной промышленности россии, стран СнГ и мира, вопросы химии, технологии и использования вяжущих веществ, эксплуатации, строительства и модернизации цементных предприятий, в том числе специальных вяжущих материалов, экономии топливно-энергетических ресурсов и использования отходов, а также смежные вопросы. Материал, передаваемый в редакцию, должен сопровождаться: • рекомендательным письмом руководителя предприятия (института, отдела, кафедры) с указанием, является ли этот материал диссертационным; • подтверждением, что эта статья предназначена для публикации в журнале «Цемент и его применение», ранее нигде не публиковалась и в настоящее время не передана в другие издания; • сведениями об авторах с указанием полностью фамилии, имени, отчества, ученой степени, ученого звания (звания в негосударственных академиях наук не указывать), должности, контактных телефонов, почтового и электронного адресов (отдельное приложение). Статьи могут передаваться в редакцию по электронной почте или на электронном носителе с распечаткой материала, обязательно подписанной всеми авторами. в каждой статье должны быть приведены следующие данные: • название статьи; • реферат; • ключевые слова. Каждое ключевое слово или словосочетание отделяется от другого запятой или точкой с запятой. Эти данные должны приводиться на русском и английском языках; • список литературы; • коды УДК. Текст статьи должен быть представлен в формате .doc, .docx или .rtf и включать в себя весь иллюстративный материал и таблицы. рекомендуемый объем — не более 8 страниц, включая рисунки и таблицы, размер шрифта 14, печать через 1,5 интервала, поля 3–4 см. При объеме текста более 6000 знаков (с пробелами) статья должна иметь рубрикацию. Для экспериментальных работ рекомендуем следующие подзаголовки: введение (Постановка проблемы), Методика и исходные материалы, результаты, Обсуждение, Заключение (выводы). Методика должна быть изложена таким образом, чтобы читатель мог воспроизвести описываемый эксперимент. растровый иллюстративный материал (фотографии, коллажи и т. п.) должен предоставляться также в виде файлов отдельно от текста с разрешением не менее 300 точек на дюйм (300 dpi). форматы принимаемых иллюстративных материалов должны быть открытыми и общедоступными. Плата за публикацию статей аспирантов не взимается. редакция допускает отдельные отклонения от перечисленных требований, если сочтет причины этих отклонений уважительными. Журнал входит в перечень рецензируемых изданий ВАК, в которых должны быть опубликованы основные научные результаты диссертаций на соискание ученой степени кандидата наук/доктора наук по специальностям: 05.02.13 – Машины, агрегаты и процессы (технические науки), 05.17.11 – Технология силикатных и тугоплавких неметаллических материалов (технические науки), 05.17.11 – Технология силикатных и тугоплавких неметаллических материалов (химические науки), 05.23.05 – Строительные материалы и изделия (технические науки). URL: https://www.researchgate.net/publication/26314392 (дата обращения 06.02.2023). 5. Deckers M., Stettner W. Die Wirkung von Mahlhilfsmitteln unter besonderer Berücksichtigung der Mühlenbedingungen (Effect of grinding aids with special consideration of the mill conditions) // Aufbereitungs-Technik. 1979. Vol. 10. P. 545—550. 6. Blake T.D. The physics of moving wetting lines // J. of Colloid and Interface Sci. 2006. Vol. 1. P. 1—13. 7. Moothedath S.K., Ahluwalia S.C. Mechanism of action of grinding aids in comminution // Powder Tech. 1992. Vol. 71, N 3. P. 229—237. 8. Teoreanu I., Guslicov G. Mechanisms and effects of additives from the dihydroxy-compound class on Portland cement grinding // Cement and Concrete Res. 1999. Vol. 29, N 1. P. 9—15. 9. Marceau M.L., Caffero A.M. Data analysis of electrostatic charge in a finish ball mill // Portland Cement Association. Res. & Development Information. 2005. Serial N 2855. 10. Биргер И.а., Мавлютов р.р. Сопротивление материалов. М.: наука, 1986. 560 с. 11. Бутягин П.Ю., Стрелецкий а.н. Кинетика и энергетический баланс в механохимических превращениях // физика твердого тела. 2005. Т. 47, № 5. С. 830—836. 12. Овчаренко а.Г., раско С.л. Электростатическая безопасность пожаро- и взрывоопасных производств. Бийск: алт. гос. тех. ун-т, БТИ. 156 с. 13. Зимон а.Д. адгезия пыли и порошков. М.: Химия, 1976. 432 с. 14. Lacks D.J. Effect of particle size distribution on the polarity of triboelectric charging in granular insulator systems // J. Electrost. 2007. Vol. 65. P. 107—112. 15. Mehrani P., Grace H.T. Electrostatic charge generation in gas solids fluidized beds // J. of Electrostatics. 2005. Vol. 63. P. 165—173. 16. Mehrani P., Grace H.T. Electrostatic behavior of different fines added to a Faraday cup fluidized bed // J. of Electrostatics. 2007. Vol. 65. P. 1—10. 17. Forward K.M., Lacks D.J., Sankaran R.M. Charge segregation depends on particle size in triboelectrically charged granular materials // Phys. Rev. Lett. 2009. Vol. 102. P. 028001 18 Rowley G. Quantifying electrostatic interactions in pharmaceutical solid systems // Int. J. Pharm. 2001. Vol. 227. P. 47—55. 19. Kok J.F., Lacks D.J. Electrification of granular systems of identical insulators // Phys. Rev. 2009. Vol. 79. P. 051304. 20. Hongxiang Y., Li’an M., Li X. Numerical simulation of particle size effects on contact electrification in granular systems // J. of Electrostatics. 2017. Vol. 90. P. 113—122. 21. Дерягин Б.в., Кротова н.а., Смилг в.П. адгезия твердых тел. М.: наука, 1973. 280 с. 22. Bischof C., Possart W. Adhasion Theoretishce und experimentelle Grundlagen. Berlin: Akademie Verlag, 1983. 23. волков в.а. Коллоидная химия. Поверхностные явления и дисперсные системы. М.: МГТУ, 2015. 659 с. 24. Mishra R.K., Flatt R.J., Heinz H. Force field for tricalcium silicate and insight into nanoscale properties: cleavage, initial hydration, and adsorption of organic molecules [Электронный ресурс]. URL: https://www.linkedin.com/in/ratank-mishra-015b846 (дата обращения 06.02.2023). 25. Mishra R.K., Fernandez-Carralunya L.J., Flatt R.J., Heinz H. A force field for tricalcium aluminate to characterize surface properties, initial hydration, and organically modified interfaces in atomic resolution // Dalton Trans. 2014. Vol. 43. P. 10602— 10616. 26. Бородулин в.н. Диэлектрики. М.: Изд-во МЭИ, 1993. 60 с. 27. Shakhova L.D., Chernositova E.S., Denisova J.V. Flowability of cement powder // IOP Conf. Ser.: Materials Sci. and Engineering. 2018. Vol. 327, N 3. Article number 032049.

112 p. 6—11 NEWS RUSSIA The program of industrial mortgages According to Decree No.716-r of the RF Government dated 27 March 2023 over RUR 1 billion will be allocated in 2023 for the support of the industrial mortgage program - granting soft loans to businesses for the purchase of real estate for industrial production purposes. As Mikhail Mishustin, Chairman of the Government of the Russian Federation, noted, this will allow companies to receive concessional loans for the purchase of industrial premises in the total amount of more than RUR 45 billion, which will be a substantial help for them. The industrial mortgage program was launched by the Government on the instructions of the President in September 2022 and aroused great interest on the part of business. This mechanism allows industrial enterprises to optimize the cost of acquiring new premises, and also contributes to the expansion of production, the launch of promising projects, and the creation of new jobs. Loans under the program are granted for up to seven years at a preferential rate of 5% per annum. For innovative technology companies, the rate is even lower - 3% per annum. The maximum loan amount is RUR 500 million. The difference between the preferential and market rates will be compensated by the state. Taking into account the funds allocated by the order, the total amount of subsidizing the program in 2023 will exceed RUR 1.3 billion. In the near future proposals will be prepared to expand the parameters of industrial mortgages. It is assumed that it will be possible to obtain a preferential loan not only for the purchase of real estate for further industrial production, but also for the construction, modernization and reconstruction of such facilities. Action plan for the second phase of adaptation to climate change The Government of the Russian Federation by its Order No. 559-r dated March 11, 2023 approved the National Action Plan for the second phase of adaptation to climate change for the period until 2025. The document contains 17 measures grouped in federal, sectoral and regional blocks. In particular, the plan provides for development and implementation of new technological solutions aimed at climate studies; formation of a list of best Russian and international practices in adaptation of industries to climate change; annual monitoring and evaluation of the effectiveness of the existing adaptation measures. Preferential financing of green initiatives RF Government Resolution No. 373 of March 11, 2023, expanded the list of areas of green initiatives for which concessional financing can be raised through special bonds or loans. In particular, projects related to the construction of energy-efficient housing, cleaning and restoration of water bodies, creation and modernization of infrastructure for direct capture of greenhouse gases from the environment, as well as capture and utilization of landfill gas with subsequent production of energy, will now be eligible for preferential financing. The signed document amends the Government Decree No.1587 dated September 21, 2021. Changes in the method of calculating the estimated cost of construction The Methodology of calculation of indexes of changes in construction cost estimates was amended and came into force on March 24, 2023. The updated document will supplement the regulatory and methodological framework to ensure the transition to the resource-index method. CEMROS Katavsky Cement. In 2023, the company plans to upgrade the cement mill - it will be converted from an open to a closed circuit cement grinding process. This will provide an additional output of high quality cement of stable quality and energy saving up to 30%. The cost of the project is about RUR 240 million, of which 107.8 million was lent to the plant by the Industrial Development Fund in the form of a soft loan under the "Development Projects" program. At the moment foundations are being poured for the frame and necessary equipment is being purchased - a highly efficient separator, a fan, electrical equipment and a control system for closed-circuit grinding. It is also planned to renovate the armor liner and grinding bodies. The mill's annual output after the upgrade will total 114 kt of cement. The mill is scheduled to be launched in September 2023. Maltsovsky Portland Cement Automated process control systems development. Engineers and programmers of the plant develop automated process control systems and install them in the rotary kilns of the burning shop. In 2022 a high-tech control panel with a modern interface was installed on kiln No. 9, which saved more than RUR 33 million. By now a modern operator workstation has also been created at rotary kiln No. 11. The new automated process control system is based on equipment from Russian manufacturers, using domestic hardware and developments. The line for producing precipitation electrodes. After a 20-year pause, the line for producing precipitation electrodes for UG 74/2 electric precipitators of rotary kilns was relaunched at the enterprise. This line allows to meet the demands of all companies of the CEMROS Group. The production line is supplemented with a welding stand, where the electrodes are equipped with fixing and guiding elements. The walking excavator. The company modernized the walking excavator ESh-11/70 No. 5, which is used in the central section of the chalk quarry. The work began in December 2022, the cost of the project exceeded RUR 27 million. Mikhailovcement. Within the framework of the modernization program of CEMROS Group of companies, investments in which have already exceeded RUR 3 billion, a number of activities are carried out at the Mikhailovsky Cement Plant. Priority is given to issues of environmental protection at the plant, and the main environmental project is the replacement of electric precipitators. In total it is planned to allocate more than RUR 1.6 billion for these purposes. The electrostatic precipitators will be completely reconstructed at three rotary kilns. English pages

113 The plant's vehicle fleet continues updating - new dump trucks, an excavator and a bulldozer were added to the fleet. AO HC Sibcem Environmental protection. Siberian Cement Holding Company continues its projects aimed at increasing the level of environmental safety of production facilities. In 2022 the total amount of funds invested by the company in modernization of operations, including in accordance with the standards and requirements of environmental legislation, amounted to RUR 6.4 billion (including VAT and the cost of leasing facilities received in 2022). Re-equipment of the plants is continuing in 2023, and the work package also includes measures taken to reduce the environmental impact. In particular, Topkinskiy Cement is upgrading the electric precipitator of rotary kiln No. 2. The project, worth about RUR 665 million, is scheduled for completion in 2024. With the launch of the equipment which allows to clean the waste gases to the level of 99.9%, all the process lines of the plant will be equipped with powerful ESPs. The cement plant in Iskitim expects to commission a new bag filter at process line No. 7 by the end of the year. The plant is also installing an automatic measuring system for monitoring emissions at the smokestacks of rotary kilns, which provides information to the general online access. The equipment is planned to be commissioned in 2024. Modern bag filters and high efficiency gas cleaning systems are also installed in the cement mill of the new grinding department of the Krasnoyarsk cement plant, which will be put into operation in the summer of 2023. In addition, the company is building an enclosed clinker storage facility to eliminate dust during storage and handling of the product and a 16,000-ton silo farm fitted with the latest generation of aspiration systems. AO Angarskcement. The company has improved the accuracy of product filling by upgrading the packaging complex. Eight new dosing devices (according to the number of machine modules) were installed on the packaging machine, which made it possible to significantly increase cement packing accuracy into 50 and 25 kg paper bags due to fully closed filling channels and other technological solutions. In addition, specialists in automation of the process control system upgraded the software of the packaging complex, including control belt scales, which also helped to improve the accuracy of dosing products. According to GOST the deviation of the average net weight of cement in bags from the net weight indicated on the package should be within 0.5 to –0.2 kg. After the upgrade of the packaging complex the error has become much less than the minimum allowable values and is now counted in dozens of grams. OOO Sibirsky Beton. The company has completed upgrading of weighing equipment - its Krasnoyarsk, Kemerovo sites have new truck scales for static weighing of vehicles, and Kuzbass plant has platform scales 18m long and 80 tons of load capacity. Similar equipment has been in use at production area No. 1 of the Krasnoyarsk division since July 2022. Putting the devices into operation enabled the company to automate and in general to considerably improve the process of weighing trucks. The total cost of installing and upgrading the weighing equipment was about RUR 13.3 million. Vostokcement Group of Companies New clinker burning process. Vostokcement has introduced a unique combined clinker burning process and was the first in Russia to receive a patent for this technology. Two flows - sludge and dry raw material mix - are fed into the kiln simultaneously and mixed only after the sludge is dry. The transition to the new method of clinker production makes it possible to reduce fuel consumption and, consequently, emissions into air. The first experiments were carried out at the Teploozersky Cement Plant. They were followed by semi-industrial tests at Yakut-Cement. New type of packaging. At the Tiger Mix plant they started packing cement CEM I 42,5N, produced by AO Spasskcement, into 5 kg bags convenient for private consumers during local repair or construction work. Cement is packaged on the same equipment as dry construction mixes. Bags of cement are packed by 3 pieces into cardboard boxes, and then palletized. One pallet holds 180 bags. Cement in 5 kg packages will be sold wholesale (from 1 pallet) and retail. AO Spasskcement. The company's Sakhalin affiliate, Sakhalin-Cement, upgraded the cement mill, which allows it to increase its capacity from 15 to 20 tons of cement per hour. In the course of the work the armored lining, the pipe auger, the frontal plates, and the inter-chamber partitions were replaced, and the number of chambers was reduced from three to two. Its modernization is one of the important steps for the planned increase of cement production by Sakhalin-Cement to at least 100 kt per year. OOO Asia Cement The company has successfully completed tests of a new type of cement - CEM I 52,5N ZhI and received a certificate of compliance with GOST 55224-2020. This type of cement is produced on the basis of Portland cement clinker of normalized chemical and mineralogical composition without using auxiliary components and is intended for production of road pavement concrete; bridge structures, including reinforced concrete pipes, sleepers, power transmission line supports; production of concrete and reinforced concrete precast and castin-place structures of concretes of B 35 class and higher. BELARUS State-owned enterprise “Managing company of BCC holding” OAO Krasnoselskstroymaterialy The tertiary gas duct. The tertiary gas duct of the clinker burning system was replaced at Branch No. 1 "Cement Plant". During its lining we switched from the former ring lining with bricks to bonded lining. Four expansion joints were replaced with new ones, and the entrance to the decarbonizer was rebuilt, the flue damper in the gas duct was replaced, and the size of the manholes was increased, which facilitated access for local repairs. The peat generator. With the launch of the dry process clinker production line the peat generator was put into permanent operation after an overhaul. The vertical three-roller mill installed at the plant requires heat supply from an additional source, which previously was a gas generator. The construction of the heat generator, which consumes about 8 tons of Belarusian peat per hour, allowed the company to almost completely abandon the use of imported natural gas and thereby achieve significant cost savings.

114 JANUARY—FEBRUARY 2023 More than 20 years ago the magazine "Cement and its Applications" for the first time published a thematic compilation of materials provided by cement manufacturers about the activities and plans of companies in the industry. Such publications have become regular, with the previous one dating back to 2022. The challenges faced by cement companies and the ways of addressing them have remained fundamentally the same, but much has been changing in recent years. In order to save money and resources and achieve great results, it is not enough to do things the way we used to. Often companies have to reconfigure the logistics of production upgrades, repairs, spare parts supply, and cement marketing logistics. Digital technologies become indispensable in production sector as a guarantee of stability of technological processes and quality of the end product, and in sales sector - as an important component of work with customers. Environmental regulations are becoming stricter and the reduction of CO2 emissions is on the agenda. One of the consequences of this is that companies are intensively developing the production of new types of cement with mineral additives and increasing the use of alternative fuels. At the same time, the need of the construction sector for an indispensable material, which is reflected in programs for the construction of residential and infrastructure facilities, remains the most important thing. The Strategy for Development of the Construction Industry and Housing and Public Utilities Sector of the Russian Federation for the period through 2030 and the forecast till 2035 approved by the RF Government in October 2022 envisages an increase in the housing commissioning rates in the country: the target figure for 2021-2030 being over 1 billion m2 (from 2011 till 2021, 859.9 million m2 were commissioned). The document sets the objective of ensuring stable, long-term demand for housing, including through the development of mortgage lending. New opportunities have been opened by the launch of the preferential industrial mortgage program. A comprehensive plan for the modernization and expansion of highway infrastructure for the period up to 2024, the national project "Safe and Quality Roads" and others are being under way. The comprehensive state program "Construction" of the Russian Federation envisages, in particular, an increase by 2027 in the commissioning of capital construction projects included (to be included) in the federal targeted investment program by no less than 1.5 times as compared with the same indicator of 2022. The list of the RF President's instructions, formed in August 2022, obliges the RF Government to provide additional funding for programs and activities in the construction sphere. The need to ensure the proper quality of construction materials and the appropriate control of their characteristics is especially emphasized in the key documents, which set the vectors of the construction development. The support measures for the construction industry taken by the President and the RF Government are also aimed at ensuring the development of cement and other building materials production. This is one of the important factors that allow the cement industry to look into the future with confidence. Editorial Board of "Cement and its Applications" Journal TODAY: AN INSIDER’S VIEW CEMENT INDUSTRY OF THE POST-SOVIET COUNTRIES

115 JANUARY—FEBRUARY 2023 OOO Aluminate Cement Plant 130 OOO Asia Cement 130 ATOM Cement 131 AO Bakhchisaray Stroyindustriya Combined Works 131 OOO Cemix 131 AO Chechencement 131 OOO Magnitogorsk Cement and Refractory plant (MCOZ) 132 The cement plant of OOO Norilsk Support Complex 132 AO Sebryakovcement 132 ARMENIA 133 OOO Hrazdan Cement Corporation 133 AZERBAIJAN 133 Norm Sement 134 BELARUS 134 KAZAKHSTAN 134 International Cement Group 135 TOO Alacem 135 TOO Sharcem 135 Korcem 135 TOO Gezhuba Shieli Cement Company 135 TOO PO Kokshe-Cement 136 TOO SAS-Tobe Technologies 136 TOO Semey Cement Plant Industrial Company 137 KYRGYZSTAN 137 United Cement Group 137 ÎÀÎ Kant Cement Plant 138 OOO South Construction Materials Combined Works 138 MOLDOVA 138 ZAO Rybnitsky Cement Combined Works 138 TAJIKISTAN 138 International Cement Group 138 OOO Mohir Cement 138 OOO MPO Zhongtsai Mohir Cement 138 UZBEKISTAN 139 AKKERMANN CEMENT 122 AKHANGARANCEMENT 122 United Cement Group 139 AO Bekabadcement 139 AO Qizilqumsement 139 AO Quvasoysement 139 Yangiyul grinding station 139 RUSSIA 116 CEMROS 118 Welcome address to the readers of the journal by Vyacheslav Shmatov, General Director of CEMROS 118 Belgorodsky Cement 120 Katavsky Cement 120 Kavkazcement 120 Lipetskcement 121 Maltsovsky Portland Cement 121 Mikhailovcement 121 Mordovcement 121 Nevyansky Cementnik 121 Oskolcement 121 Peterburgcement 121 Pikalevsky Cement 119 Savinsky cement plant 119 Sengileevsky cement plant 121 Ulyanovskcement 119 Voronezh branch of CEMROS 121 Zhigulevskie Stroymaterialy 119 AKKERMANN CEMENT 122 AKKERMANN CEMENT 122 Gornozavodskcement 122 Alfi Group Holding Company 123 Atakaycement 123 Uglegorsk Cement 123 CEMENTUM 123 Ferzikovo Cement Plant 123 Shchurovsky Cement Plant 124 Volsky Cement Plant 124 Voskresensk Cement Plant 124 OOO Gazmetallproekt 124 Novoroscement 124 Verkhnebakansky Cement Plant 125 Siberian Cement Holding Company 125 Angarskcement 126 Iskitimcement 126 Krasnoyarsk Cement 127 TimlyuyCement 127 Topkinsky Cement 127 OOO SLK Cement 127 Sukholozhskcement 127 Korkino 127 Omsk 127 Vostokcement 128 Spasskcement 128 Teploozersky cement plant 129 Yakutcement 129

116 JANUARY—FEBRUARY 2023 The main indicators of construction works and production of main types of construction materials products and structuresin 2022 as well as prices for them in Q4 2022 are given here according to Rosstat data. Construction The cost of construction works performed in the Russian Federation as a whole and in its Federal districts in 2022 are shown in table 1. Over this period, 434.1 thou. residential and non-residential buildings were commissioned (the figure for residential buildings was 413.0 thou.). Their gross floor area and total structural volume were 160.2 million m2 and 695.2 million m3, respectively (corresponding figures for residential buildings were 126.7 million m2 and 467.8 million m3). Data on the total floor area of residential buildings commissioned in 9m 2022 is given in table 2. Construction materials For data on the production of main types of construction materials, products and structures in Russian Federation in 2022 see table 3. Data on output of different types of cement for the same period is given in table 4, and data on cement production in federal districts of Russian Federation in 2022 is shown in table 5. Prices for construction materials In October, November and December 2022 average producers’ prices at the domestic market amounted to RUB 5,158; 5,147; 5,111 per tonne of cement and RUB 4,743; 4,927 and 5,062 per cubic meter of ready-mixed concrete, respectively. The average purchase prices for basic construction materials, parts and structures In October, November and December 2022 are given in table 6. The average purchase prices for cement in federal districts and cities of Russian Federation are shown in table 7. RUSSIA Table 1 The cost of construction works performed Federal district bln RUB* as percentage to 2021** Russian Federation*** 12,865.5 105.2 Central 3,682.5 112.0 North-West 1,229.8 89.5 South 944.5 100.5 North Caucasus 529.3 104.4 Volga basin 2,245.4 111.0 Urals 1,762.1 92.4 Siberia 1,406.9 108.4 Far East 1,058.9 107.9 * In actual prices of the day. ** In comparable prices. *** Consolidated results for the Russian Federation include updated parameters of informal activities at the Federal level that are not included in the Federal districts figures. Table 2 Total floor area of residential buildings commissioned Federal district Total floor area Total floor area in the buildings commissioned by individual developers thou. m2 as percentage to 2021 thou. m2 as percentage to 2021 Russian Federation 102,713 111.0 57,203 116.5 Central 32,878 112.6 17,648 123.6 NorthWest 11,248 108.4 4,842 108.7 South 13,761 114.7 8,461 125.4 North Caucasus 5,970 126.5 4,354 133.7 Volga basin 18,541 106.5 11,821 111.1 Urals 8,460 110.3 3,814 100.3 Siberia 8,288 102.6 4,278 99.0 Far East 3,567 114.5 1,986 123.8 Table 3 The output of cement and other main types of construction materials, products and structures Product Output Cement, thou. t 60,667.0 Ready-mixed concrete, thou. m3 53,416.3 Precast constructions and parts, thou. m3 26,516.4 Construction brick (including stones) made with cement, concrete or cast stone, mln arb. bricks 2,231.5 Ceramic non-refractory construction brick, mln arb. bricks 5,571.7 Table 4 Cement production by type Type of cement Production, kt Portland cement, aluminous cement, slag cement and similar hydraulic cements 60,667.0 Construction-related cements 59,107.5 – Portland cement without mineral additives 38,663.0 – Portland cement with mineral additives 18,596.5 – Slag Portland cement 1,746.8 White Portland cement 156.6 Oil-well Portland cement 1,055.3 Aluminous cement 13.5 Other cements 329.4 Table 5 Cement production by Federal districts Federal district Production, kt as percentage to 2021 Russian Federation 60,667.0 101.3 Central 15,380.0 101.5 North-West 3,418.1 98.6 South 9,760.7 101.8 North Caucasus 2,611.2 114.2 Volga basin 13,351.4 99.1 Urals 6,059.9 100.4 Siberia 6,537.6 97.4 Far East 3,548.2 110.8 Table 6 Average purchase prices for basic construction materials, parts and structures paid by contractor companies for the end of October, November and December 2022, RUB Material October November December Constructionrelated cements, t 6,645 6,687 6,676 Ready-mixed concrete, m3 6,125 5,999 6,033 Ceramic nonrefractory construction brick, thou. arb. bricks 17,970 16,950 15,545 Silicate and slag brick, thou. arb. bricks 12,290 12,323 12,595 Crushed stone, m3 2,031 2,076 2,070 Gravel, m3 1,813 1,389 1,447 Table 7 Average acquisition prices for cement in Federal districts and several cities in October, November and December 2022, RUB per tonne Federal district, city* October November December Central 6,438 6,413 6,435 North-West 6,873 6,473 6,504 South 7,238 7,215 7,197 North Caucasus 5,753 5,847 6,449 Volga basin 5,960 6,063 6,172 Urals 7,009 6,454 6,624 Siberia 7,681 7,611 7,485 Far East 10,848 10,540 11,015 City of Moscow 7,301 6,323 9,089 City of St. Petersburg 6,561 6,143 6,142 EVERYTHING ABOUT CEMENT INDUSTRY OF THE POST-SOVIET COUNTRIES

117 JANUARY—FEBRUARY 2023 Production and markets Transportation Facilities and raw materials bases Holdings and enterprises EVERYTHING ABOUT CEMENT INDUSTRY OF THE POST-SOVIET COUNTRIES Special English language issue Cement and its Applications For advertising and purchase please contact: PetroCem Ltd. Tel.: +7 812 2421124. E-mail: [email protected]. www.jcement.ru • www.petrocem.ru the most comprehensive information on cement industry in the post-Soviet countries

118 JANUARY—FEBRUARY 2023 Dear colleagues, friends! Over the past few years, our industry has been going through some neverending changes. Not a day goes by without new challenges for cement business appearing, and we cannot even rely on tried and tested anti-crisis practices that are made irrelevant by that change. Nevertheless, the cement industry in Russia continues to grow and remains a guarantor of continuous operations of the domestic construction business. Against the backdrop of new economic reality, it is of vital importance to learn to adapt to the new rules of the game and relentlessly offer solutions and trends before others will do it for you. Therefore, responding to tectonic shifts in historical scenery, in February 2023 we decided to rename the company. CEMROS has retained the leadership and scale of the former brand, adding new qualities – expertise, responsibility and commitment. Being the largest cement producer in the country, our organization maintains domestic leadership and lives up to a strategic purpose, helping to grow the economy of the country. After the change of ownership in the summer of 2021, we "rebooted" the company. First of all, the new management revamped organization's business logic in line with sustainability principles with a clear focus on production efficiency, sales growth and new corporate culture. We streamlined production processes, launched plant modernization programs, built an e-commerce platform and increased direct contracts. Our valuable factory employees had seen their salaries increased twice throughout the period, and in many our locations and communities, the company makes impact investments. CEMROS today: • 16 cement plants and more than 30 quarries; • every third ton of cement sold in Russia; • 10 thousand employees; • more than 70 delivery regions; • extensive experience and expertise in the construction industry; • "Japanese" philosophy of business management: customer-centricity, care for employees, "lean" production, community investment and ESG initiatives; • new corporate culture where openness and initiative come first; • new business opportunities, products and services. In times of global change, one must steer it to stay ahead. Forewarned is forearmed. We might have changed the name, but we have not dropped our momentum, capacity, knowledge and experience in order to carry out our plans and shape the future of the country — solid, big and bright. . Sincerely, CEMROS General Manager Vyacheslav Shmatov

119 JANUARY—FEBRUARY 2023 CEMROS CEMROS is a diversified industrial holding company, one of the leaders of the cement industry in Russia. CEMROS unites 16 cement plants of the country: • ZAO Belgorodsky Cement, • AO Kavkazcement, • AO Katavsky Cement, • AO Lipetskcement, • AO Maltsovsky Portland Cement, • AO Mikhailovcement, • AO Mordovcement, • AO Nevyansky Cementnik, • ZAO Oskolcement, • OOO Petersburgcement, • AO Pikalevsky Cement, • ZAO Savinsky Cement Plant, • OOO Sengileyevsky Cement Plant, • AO Ulyanovskcement. • Voronezh branch of CEMROS, • ZAO Zhigulevskie Stroymaterialy. CEMROS' share in the Russian cement market is close to 30%. The company also owns quarries of aggregates. Plants of the company are located in 13 regions: the Republic of Mordovia, Karachay-Cherkessia Republic, the Arkhangelsk, Belgorod, Bryansk, Voronezh, Leningrad, Lipetsk, Ryazan, Samara, Sverdlovsk, Ulyanovsk and Chelyabinsk regions. CEMROS defines its mission as creation in harmony with nature and implements it in all areas of its activities. By increasing production volumes and investing in new capacities, the company creates conditions for mass housing construction and contributes to improving people's living conditions. Replenishing the budgets of the regions of its presence, the holding contributes to the development of their economy and ensures the growth of the well-being of residents. By acquiring and developing enterprises, the company creates new jobs and stabilizes the social climate. By implementing a set of environmental protection measures, it constantly monitors the state of the environment and contributes to improving the environmental situation. The goal of CEMROs is development. In the strategic plans of the holding, the priority areas of development are: • providing the Russian construction industry with high-quality materials for the implementation of housing and infrastructure projects. • transition to a new technological platform through the construction of modern factories and modernization of existing enterprises. • improving energy efficiency and environmental friendliness of production. All this allows the company to improve energy efficiency, labor productivity and the quality of finished products. We are sure that we have chosen the right path. The holding is aimed at further improving the economic and production indicators of its constituent enterprises, as well as creating new benchmarks for the development of the cement industry in Russia and the CIS. The CEMROS strategy is an effective leadership strategy. The consolidation of industry enterprises and the introduction of a modern management system allow CEMROS to flexibly respond to changes in territorial demand, ensure stable utilization of its own enterprises and implement an active investment policy. In 2022 CEMROS once again confirmed its leading position in the Russian cement market. The CEMROS team faced not the easiest conditions, but thanks to large investments in the modernization of production facilities they managed to significantly increase productivity and product quality, as well as to expand the range of manufactured building materials. In 2023 the company plans to continue its development and sets up ambitious goals. For the last few years CEMROS has been making a stake on the development of specialized cement lines. Thus, the company has patented the technology for producing belite clinker and belite cement, which can be used in the construction of the most complex projects. New types of cements have optimal rate of strength development, and structures made of materials based on them are characterized by increased durability, so such cements can be used for complex works in marine environment or for construction of concrete roads. Moreover, in 2022 CEMROS began to produce AutoGrunt — a complex mineral binder (CMB) of its own design. CMB is selected individually for specific soils. Its maximum dosage for strengthening soils is from 4 to 8% (21–42 kg per 1 m2). Products of the holding company can also be in demand at full repair of roads according to the cold regeneration technology. Cost saving when using this technology is about 15–30%. Within the framework of the federal project Closed Loop Economy many cement producers have embarked on using alternative fuels (AF). RUSSIA ZAO Belgorodsky Cement. Plant view OOO Petersburgcement. Plant view AO Katavsky Cement. Rotary kilns

120 JANUARY—FEBRUARY 2023 Some CEMROS plants already have experience in using various types of AF in production. In 2023, improving the environmental efficiency of cement plants will become one of the company's priorities. CEMROS aims to reduce CO2 emissions by the holding's plants by 10 % by 2030, including through the use of secondary resources in production. The plants in Lipetsk and Stary Oskol already use metallurgical slag and TPP ash as "carbonfree" mineral additives. This experience will be extended to other factories of the company. The plants in Mordovia and Leningrad Oblast will start using AF, RDF pellets. In order to maintain their leadership, producers have to offer more flexible sales and delivery terms to their customers. That is why the important tasks for cement producers will be to improve product quality and expand the range of services offered. First of all, it depends on the communication between the producer and the consumer. Barriers in the form of unnecessary approvals, unnecessary calls, useless letters can significantly increase the delivery time of products. That is why digital cement sales services come to the fore for large companies. CEMROS customers can place orders online in the Personal Area 24/7, track the status of fulfillment and view orders that have been completed. Currently, more than 90% of all the company's sales are made through the Client Area on its website. In 2022, 60 new cement trucks were added to the company's fleet. In addition, the fleet of quarry equipment is being renewed and the technology of planning railway routes is being introduced. Today the company successfully copes with the tasks of providing the factories with the necessary products, and the clients receive quality building materials in due time. Thanks to the development of digital services of CEMROS its employees can monitor online the movement of goods of the holding company and promptly address any issues that may arise. CEMROS has launched the "Making the World a Better Place" program to develop the social environment around each of its enterprises. ZAO Belgorodsky Cement In 2022 the plant started producing a new cement CEM II/BSh 32,5R with the slag content up to 35%. Modern laboratory equipment was put into operation at the plant: a sample packing machine, a Blaine device and an air-jet sieve, which makes it possible to control the quality of manufactured products by the residue on the sieve of 45 m. AO Katavsky Cement The range of products manufactured by the company: • according to GOST 31108–2020 — CEM I 42,5N, • according to GOST 1581–2019 — PCT I-50. In 2022868.0 kt of cement were produced and 877.6 kt of cement were shipped. In 2022 the company revamped the raw mill control systems and replaced obsolete power equipment as part of the import substitution program. The savings from modernization will amount to about 4 million a year. The new mill control system can improve the efficiency of machinery operation and reduce the specific power consumption from 33 to 30 kWh per 1 ton of raw meal as well as eliminate idling of the mills' auxiliary equipment. Thanks to the new control system the personnel of the plant can control online the whole production cycle from marl supply for grinding to grinding and mixing in the mills with additives (gypsum, iron-containing drosses, etc.). The company also successfully commissioned a new technical water filtration and treatment system, which increased the efficiency of compressors and reduced specific energy consumption for compressed air production by 10 %. Air outlet temperature decreased from 270 to 160 °С, which increased compressor efficiency. Their maintenance interval increased from 6 to 24 months, reducing downtime of compressor equipment from 8 to 2 days a year. Also working time which was usually spent for cleaning of heat exchangers (about 100 man-hours for each compressor) was saved. In addition, the plant's specialists conducted industrial tests of kiln No. 3 after installation of a calciner and a static cooler grate, which resulted in a 32% increase in the productivity of the process line and a significant reduction in specific fuel and energy consumption. AO Kavkazcement The product range of the company includes cements: • according to GOST 31108–2020: — CEM II/A-I 42,5N; — CEM II/A-I 32,5N; — CEM I 32,5R; — CEM 042,5N; • according to GOST 22266–2013: — CEM II/A-Sh 42,5N SR. AO Lipetskcement. Cement silos AO Maltsovsky Portland Cement. Repair works AO Mordovcement. Plant view AO Nevyansky Cementnik. Rotary kilns AO Kavkazcement. Rotary kilns

121 JANUARY—FEBRUARY 2023 OOO Petersburgcement. Plant view Voronezh branch of CEMROS. Plant view In 20221.8 million tons of cement were produced. In 2022, the plant upgraded the burning process line and installed a static grate on the cooler of rotary kiln No. 2. The IT infrastructure of the plant was upgraded and the fleet of special equipment was renewed. The total investment in the projects amounted to RUR 300 million. The planned volume of investments in 2023 is RUR 630 million. Among the top-priority tasks are modernization of the cement grinding shop with conversion of cement mill No. 1 to closed circuit grinding and installation of a new palletizing line. AO Lipetskcement In 2022 the plant started producing slag Portland cement CEM II/V-Sh 42,5N according to GOST 31108–2020. In addition to it, the plant also produces Portland cement CEM I 42,5N in accordance with GOST 31108–2020. AO Maltsovsky Portland Cement In 2022 the plant produced 1885.1 kt of clinker and 1948.3 kt of cement, including: • according to GOST 31108–2020: — CEM I 42,5N — 1153.1 kt; — CEM 042,5N — 208.8 kt; — CEM II/A-Sh 42,5N — 102.0 kt; — CEM II/A-P 42,5N — 1.1 kt; • according to TR TS 014/2011 (GOST 33174– 2014): — CEM I 42,5N DP — 14.5 kt; • according to GOST R 55224–2020: — CEM I 42,5N ZhI — 468.8 kt. 66.7 kt of cement were bagged. In 2022 the volume of investments aimed at improving the efficiency of rotary kilns amounted to RUR 221.0 million. RUR 105.3 million were spent on railway equipment renewal, RUR 48.0 million on truck fleet renewal and RUR 73.8 million on railroad track reconstruction. AO Mikhailovcement The plant produces the following cements in accordance with GOST 31108–2020: • CEM I 42,5N; • CEM II/A-Sh 42,5N; • CEM II/A-K (Sh-I) 42,5N; • CEM II/V-Sh 32,5N. At present the company is modernizing two facilities — cement mill No. 1 (after the work is completed it will be converted from open to closed circuit grinding) and ESP No. 8 on rotary kiln No. 4. AO Mordovcement The range of products manufactured by the company: • according to GOST 31108–2020: • CEM I 42,5R; • CEM II/A-P 42,5N; • according to GOST R 55224–2020: — CEM I 42,5N ZhI; — CEMI 42,5N AP; • according to GOST 33174–2014 — CEM I 42,5N DP; • according to GOST 22266–2013 — CEM I 42,5N SR. Cement for airfield pavements CEM I 42,5N AP appeared in Mordov-Cement's product range in 2022. In 2022 the company produced 3054,700 tons of clinker and 3186,100 tons of cement. 3138.8 kt of cement were shipped to customers, including: • 2,430.0 kt — by rail • 708.8 kt — by road. In 2022 the crushing plant was retrofitted, which increased its capacity from 242 to 614 t/h, and pallet manufacturing lines were purchased. Mordovсement is the only CEMROS facility equipped with an alternative fuel supply system that allows to utilize up to 500 kt of waste per year. In 2022 a SEM636D front-end loader for loading alternative fuel, 6 dump trucks, a crawler excavator, a bulldozer and 5 cars were purchased. ZAO Oskolcement The company produces the following cements: • according to GOST 31108–2020: — CEM I 52,5N; — CEM I 42,5N; — CEM I 42,5R; — CEM 042,5N; • according to TR TS 014/2011 (GOST 33174– 2014) — CEM I 42,5N DP. In 2022, the boiler house of the heat and power plant was reconstructed at the factory, inclusion separators for the cement loading section were installed, after seven years of preservation the plant for cement batching in big bags was restored and put into operation, the system for preparing the raw charge of coarse sludge was automated. OOO Petersburgcement The plant produces cements according to GOST 31108–2020: — CEM I 42,5N; — CEM II/A-Sh 32,5N. OOO Sengileyevsky Cement Plant The company produces Portland cement CEM I 42,5R according to GOST 31108–2020. Located on the banks of the Volga River, the plant has an unique transport and logistics complex: products are delivered to the consumer by both road and water modes of transport. In 2022, more than 877 kt of cement were shipped, including about 164 kt by water. Voronezh branch of CEMROS In 20221751.1 kt of cement according to GOST 31108–2020 were produced, including: • CEM I 52,5N — 537.8 kt; • CEM I 42,5N — 1158.4 kt; • CEM II/A-K (Sh-I) 42,5N — 54.9 kt. The following is scheduled to be done at the plant: • equipping the marl and chalk warehouse with a conveyor gallery, which will make it possible to supply raw material to dryer-crushers bypassing the warehouse, in case of an emergency stop of the warehouse equipment; • installing an automated system for controlling pollutant emissions in the flue gases of the clinker burning process line; • install two more powerful fans for efficient clinker cooling on a static grid in the clinker cooler; • install screws in the cement grinding line to return the accumulated grit to the process and eliminate the need to involve machinery for its removal; • equipping the site for loading clinker into gondola cars; • upgrade the cement shipment line to cement trucks by installing a vibrating screen to prevent compressed cement from reaching the consumer; • buying an excavator, a bulldozer, two forklift loaders and Gazelle car; • partially upgrading the machinery, equipment and tools of the mechanical shop, etc.

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123 JANUARY—FEBRUARY 2023 OOO Atakaycement. A panoramic view of the plant AO Uglegorsk-Cement. The burning process line The multifunctional holding company Alfi Group owns two cement factories — OOO Atakaycement and AO Uglegorsk-Cement with a total capacity of 750 kt of cement per year, managed by Upravlenie ICA (ICA Management) company. Additionally, the holding company incorporates a number of other companies that produce quicklime, gas silicate wall blocks, silicate bricks and other products. OOO Atakaycement The factory is located in Novorossiysk, Gaiduk village. OOO Atakaycement produces cement using the environmentally friendly dry process. The design capacity of the plant is 450 kt of cement per year. The company has at its disposal a deposit of cement marl with reserves of 21.9 Mt and a license to use the deposit till 2031. Currently the plant produces the following cements according to GOST 31108–2020: • CEM I 42,5N; • CEM II/A-P 42,5N. The products are shipped in bulk and also in paper bags of 50 kg. The plans of the ICA Management are as follows — to expand the product line and produce cement CEM 042,5N as well as to add a packing area for filling paper bags of 25 kg and 1,000 kg big-bags to the company's structure. Today OOO Atakaycement ships its products by road. In 2023 it is planned to resume cement supplies by rail. It will enable the company to enter new markets in Russia and neighboring countries. In 2023 it is planned to make ome improvements at the factory: to raise the product quality, increase the storage space, upgrade the production with modern quarry equipment. At present, the company is rebranding: its logo and corporate colors will be changed, as well as the appearance of the packaging. The quarry equipment — dump trucks, excavators, bulldozers, etc.— is being purchased. In 2023 one of the most important avenues for the company's development will be improving the environmental friendliness of production. It is planned to develop and adopt an Environmental Protection Policy. AO Uglegorsk-Cement The plant is located in Uglegorskiy settlement of Tatsinskiy district of the Rostov region. Uglegorsk-Cement produces several types of cement on its own raw material base and sells it throughout the Rostov region. Currently the production capacity of the plant is 300 kt of cement per year. The raw material base includes limestone and clay from Kliuchevskoe deposit in Zhirnovsky District of the Rostov Region. The fuel used is natural gas. Uglegorsk-Cement produces the following types of cement according to GOST 31108–2020: — CEM I 42,5N; — CEM II/A-Sh 42,5N. The products are shipped in bulk in cement trucks as well as in 50 kg paper bags and 1,000 kg big-bags. In order to satisfy consumers' demands more fully, the management intends to raise the plant's production capacity. Preparations are being made for modernization, which will also lower the cost of production and improve environmental friendliness. In 2023, the plant plans to reconstruct its dedusting equipment and commission additional facilities, which will enable the plant to produce 1 million tons of cement a year. PR department Alfi Group CEMENTUM The Russian CEMENTUM company emerged as a result of the decision of the international Holcim to withdraw from the Russian market and transfer Russian assets to the local management, taken in December 2022. All CEMENTUM subsidiaries continue to operate in Russia in full. CEMENTUM Group develops cement business, aggregate materials and dry mixes in the country. The company develops, manufactures and markets high-tech materials and solutions for the Russian construction industry and infrastructure. It has approximately 1,500 employees. The company currently operates four cement plants, as well as three quarries for the extraction of aggregates. The materials under the CEMENTUM brand are used in production of ready-mix concrete, reinforced concrete and lightweight concrete items, in infrastructure construction. Ferzikovo Cement Plant The design capacity of the facility is 2 million tons of clinker per year. The total volume of investments from the beginning of the project until January 1, 2022 exceeded RUR 21 billion. In 2022, the plant produced 1,859.7 kt of cement, including: • CEM II/A-I 42,5R — 1,287.1 kt; • CEM I 42,5R — 572.6 kt. The largest cement deliveries were to consumers in Moscow and the Moscow Region (1,486.7 kt), Kaluga, Tula and Tver Regions (60.5 kt; 49.1 kt and 33.9 kt, respectively). In 202261 kt of alternative fuel was used, the heat efficiency of substituting natural fuel with it reached 17%. A total of 290 kt of alternative fuel was used over 8 years. The total cost of investment projects in 2022 amounted to RUR 300 million, including the following expenditures: • for the installation of a batching station to receive RDF — RUR 45 million, • for the construction of an oil storage facility at the quarry — RUR 20 million, • for the purchase of a roller for the raw mill — RUR 40 million, • for the purchase of dump trucks for open pit operations — RUR 75 million. The planned volume of investments for 2023 is RUR 300 million. The plant and CEMENTUM plan to increase the output by producing cements with high content of mineral additives. RUSSIA RUSSIA Alfi Group Holding Company

124 JANUARY—FEBRUARY 2023 Shchurovsky Cement Plant The annual design capacity of the plant is: • for gray clinker — 1,706.4 kt, • for gray cement — 2,529.0 kt, • for white clinker — 96.8 kt, • for white cement — 108.9 kt. • In 2022 the production output was as follows: • gray clinker — 1,377.9 kt, • gray cement — 1,644.0 kt, • white clinker — 84.9 kt, • white cement — 88.0 kt. Currently the factory produces cements: • according to GOST 31108–2020: — CEM 052,5N; — CEM I 42,5N; — CEM II/A‑I 42,5N; • — according to GOST 33174–2014 — CEM I 52,5N DP; • — according to GOST R 55224–2020: — CEM I 52,5N AP; — CEM I 52,5N ZhI; • according to GOST 965–89 — PCB 1–500‑D0. Total investment costs in 2022 amounted to RUR 1,104.6 million. The major projects accomplished in 2022 are: • reconstruction of the white clinker warehouse — RUR 29.5 million; • reconstruction of the vertical slurry tanks build‑ ing — RUR 14.8 million; • construction of an additives warehouse — RUR 75.3 million; • construction of the alternative fuel feeding line — RUR 210.9 million; • replacement of the pipe conveyor belt — RUR 29.1 million. For the year 2023 the investment costs are planned in the total amount of RUR 1,189.6 million. The plans for the near future include the launch of an alternative fuel feeding line (for fuel from solid domestic waste, RDF). The planned volume of alternative fuel use by 2025 is 70 kt. Volsky Cement Plant The design capacity of the plant in clinker is 1750 kt, in cement — 1950 kt. In 2022 the plant produced 1429.5 kt of clinker and 1409.7 kt of cement. Currently the plant produces cements: • according to GOST 31108–2020: — CEM 052.5N; — CEM I 42,5N; — CEM II/A‑Sh 42,5N; — CEM II/A‑I 42,5N; • according to GOST R 55224–2020: — CEM I 52.5N AP — CEM I 52,5N ZhI • according to GOST 33174–2014: — CEM I 52,5N DP; — CEM II/A‑S 42,5N DO; • according to GOST 1581–96: — PCT I‑G‑CC‑1; — PCT I‑50; — PCT II‑50; — PCT III-ob5–50. The products are shipped to consumers in the Southern, Volga and North Caucasian Federal Districts. In 2022 investments in the equity capital amounted RUR 480.0 million, including: • for maintenance of operability of the main process equipment, buildings and structures — RUR 269.4 million • for improvement in occupational and environ‑ mental safety — RUR 9.9 million; • for upgrades to production facilities — RUR 67.5 million; • for maintenance of the general plant infra‑ structure — RUR 133.2 million. The plans for the near future are to use al‑ ternative fuel (recycling of automobile tires in the plant kilns). Voskresensk Cement Plant In 2016, due to the economic situation and a lower demand for construction materials, the plant was mothballed. CEMENTUM carried out a series of upgrades to the plant and is preparing to restart it with a capacity of up to 1 Mt of cement per year. The plant will meet all modern require‑ ments, which will significantly reduce the impact on the environment. In particular, the following will ensure meeting these requirements: — a covered clinker warehouse, — renovated equipment, — dust-collecting electrostatic precipitators, — a closed-loop water recycling system. It is planned to produce the following cements according to GOST 31108–2020: • CEM I 42,5; • CEM II/A‑Sh 32,5. A plant to produce dry construction mixtures with a design capacity of more than 100 kt per year, fitted with high-tech equipment from European and Russian manufacturers was built from scratch as part of the cement plant. The launch of the dry mix plant is scheduled for May 2023. The Voskresensk cement plant is planned to be put back into operation in June 2023. PR department CEMENTUM Ferzikovo Cement Plant Shchurovsky Cement Plant Volsky Cement Plant OOO Gazmetallproject OOO Gazmetallproject manages OAOVerkhnebakansky Cement Plant and OAO Novorosce‑ ment. In 2022, these companies produced 6,284.1 kt of cement. OAO Novoroscement Three plants which make up the joint-stock company — Proletariy, Oktyabr and Pervomay‑ sky — were founded in the late 19th and early 20th centuries. Today their total production capacity is more than 5 Mt of cement per year. The company uses both the modern dry method of production at the cement plant Pervomaysky, and the wet method of production at Proletariy and Oktyabr plants. All three plants use gas as a process fuel. The main raw material for the production of Portland cement at the company is marl from the slopes of the Markotkh Ridge, extracted by opencut method in quarries. The explored reserves of this raw material in the quarries of OAO No‑ voroscement amount to 410 Mt, and there are also significant underexplored reserves. The low natural moisture content of marl makes it possible to convert the production of cement at all plants of OAO Novoroscement to the dry method. The RUSSIA

125 JANUARY—FEBRUARY 2023 company also has a license for the Bakanskoe deposit of gaize, which is used as an active mineral additive, with total reserves estimated at 57 Mt. Thanks to its proximity to the port of Novorossiysk, OAO Novoroscement can sell cement for export. The production capacity of OAO Novoroscement allows it to produce high quality cement, of the range which can satisfy the demands of domestic and foreign buyers. All products of OAO Novoroscement are certified, diplomas of competitions and a steady demand of consumers also confirm the high quality of cement. The priority markets for the products are in the Krasnodar region, the republics of the North Caucasus, the Rostov region and the Stavropol territory. In 2022 OAO Novoroscement produced 4137.2 kt of cement, including: • according to GOST 31108–2020: — CEM I 42,5N — 2,570.4 kt; — CEM 052,5N — 908,7 kt; — CEM II/A­P 42,5N — 507,9 kt; • according to GOST 55224–2020: — CEM I 42,5N ZhI — 143,3 kt; — CEM I 42,5N AP — 3.5 kt; • according to GOST 33174–2014: — CEM I 42,5N DP — 3.5 kt. 423.0 kt of cement was bagged, of which: • in 50 kg bags — 422.8 kt, • in big-bags — 0.2 kt. 4139.4 kt of cement were shipped, including: • by road — 2,231.9 kt, • by rail — 1,907.5 kt. It is planned to build the "dry" process line No. 2 with the capacity of 2 kt of clinker per day at the Pervomaysky plant. This project will increase the share of products produced by the "dry" technology up to more than 55%. OAO Novoroscement is considering an option to implement a project of reconstruction of production line № 10 at Proletariy Plant after 2025, in order to switch it to a dry technology and to increase its productivity up to 6 kt of clinker per day. I. V. Solonin, Managing Director OAO Verkhnebakansky Cement Plant In 2012 the company commissioned a new dry process cement production line with an annual capacity of 2.3 Mt of cement. In 20222146.9 kt of cement were produced, including: • according to GOST 31108–2020: — CEM I 42,5N — 849.2 kt; — CEM II/A­P 42,5N — 133,6 kt; — CEM I 52,5N — 114.4 kt; • according to GOST 22266–2013: — CEM II/A­P 42,5N SR — 902.2 kt; — CEM I 42,5R SR — 76.3 kt; — CEM II/A­P 32.5N SR — 54.5 kt; • according to GOST 33174–2014: — CEM I 42,5N DP — 16.7 kt. 445.1 kt of cement were bagged, of which: • in 50 kg bags — 162,400 kt; • in 25 kg bags — 173,100 kt; • in big bags — 109,6 kt. 2,140.7 kt of cement were shipped, of which • by rail — 1,139.5 kt. • by road — 1,001.2 kt. In late 2022, due to demand, the Verkhnebakanskiy Cement Plant obtained a certificate for a new type of cement — CEM I 42,5N ZhI used in production of reinforced concrete items and bridge structures. The geography of deliveries of the company's products is represented by the subjects of the Russian Federation in the Southern (including the Republic of Crimea), North Caucasian, Central Federal Districts. The deliveries amount to about 3% of the total volume of cement production in the country. In 2022 a new in-line conveyor analyzer was installed at the plant to replace the existing one. In 2023 it is planned to purchase an open-pit excavator to replace the existing one. A.S. Ziskel, Managing Director Novoroscement. Proletariy cement plant view OAO Verkhnebakansky Cement Plant. Plant view Siberian Cement Holding Company Siberian Cement (Sibcem) is an industrial vertically integrated holding company established in 2004. The company operates Angarsk (Irkutsk region, Angarsk), Iskitim (Novosibirsk region, Iskitim), Krasnoyarsk (Krasnoyarsk region, Krasnoyarsk), Timlyui (Republic of Buryatia, Kamensk) and Topkinsky (Kemerovo region, Topki) cement plants, a network of concrete production sites Sibirsky beton (Siberian Concrete), transport and logistics company ZapSibCement and others. The Group employs around 6000 people. The annual production capacity of Sibcem plants is 9 million tons of cement, 750 thousand m3 of concrete, 15 million m2 of roofing, 1.7 million m2 of flat panels, 800 km of conventional pipes. The portfolio of the plants of the Holding Company includes more than 40 items of chrysotile cement products; over 250 items of concrete mixtures, fine-grained concretes and mortars; 24 types of cement (including 16 standard and 8 special types) shipped to consumers in bulk, in 25 and 50 kg paper bags (including those placed on pallets) and in 1 t big bags. In 2022, the design of paper bags for 25 and 50 kg bagging was changed, becoming uniform for all five cement plants of the holding. At the same time, the company introduced trademark product names "SIBCEM EXPERT 500", "SIBCEM PROFI 450" and "SIBCEM NORMAL 400". The holding company offers its customers certified products of consistently high quality. Modern certified laboratories and multistage control systems operate at the plants. Building materials produced by the company are in demand in Siberia, the Urals, and other regions of the country. In addition, cement is exported to Azerbaijan and Kazakhstan. RUSSIA Branded cement truck

126 JANUARY—FEBRUARY 2023 In 2022, the plants of the Group produced 5.1 Mt of cement, 7.7 million m2 of chrysotile cement products. The output of the OOO Sibirsky Beton amounted to 264,100 cubic meters of concrete and mortars; the output of the OOO Gornaya Kompaniya (Mining Company) was 80.5 kt. In 2022, RUR 6.4 billion were allocated for modernization of all facilities of the holding company inclusive of VAT (including the cost of leased assets received during the year). In 2016 Sibcem started upgrading cement mills installing high-efficiency separators due to the growing demand for high-grade separated cement: if 8–9 years ago the share of such products in the markets of Russia and the Siberian Federal District was close to 45%, by now it has grown to 70– 73%. The trend is expected to strengthen in the future. In 2022500 new gondola cars with carrying capacity up to 70 t and body volume of 88 m3 were purchased for KuzbassTransCement. Today there are over 5,200 units of rolling stock at the disposal of KuzbassTransCement — gondola and boxcars, hopper cement cars, dump cars. Cargo is transported through the territory of Russia, Belarus, Kazakhstan, Uzbekistan, Tajikistan, Mongolia and other countries. During the "low" construction season the freight cars are active transporting third-party cargoes such as sand, milled gypsum and slag, etc. In 2022 the company's own cars carried about 6.5 Mt of various cargoes, including about 2.5 Mt of cement produced by the Holding company's plants. Sibcem's in-house fleet currently consists of 62 cement trucks, which deliver products up to 400 kilometers from the plants. In 2023 three more trucks are planned to be bought. Guaranteeing a consistently high quality of products and their timely shipment, the company develops various services for customers. An example is the technical support service for transactions. The company is introducing modern IT technologies. Thus, it is possible to apply for a contract or for a shipment of cement on the official website of the Group. For the clients of OOO ZapSibCement the My Account service has been made available. АО Angarskcement The capacity of the enterprise is 1.3 Mt of cement per year. The products are made using the wet method. The range of products includes: • standard cements: — CEM 052,5N; — CEM 042,5N; — CEM I 42,5N; — CEM II/A-G 32,5R; • special cements: — CEM I 42,5N AP; — CEM I 42,5N DP. In 2022766.9 kt of cement were produced. The geography of Angarskcement's sales includes the Irkutsk Region, the Republic of Buryatia and the Trans-Baikal Territory. Cement is shipped in bulk, in 25 and 50 kg bags and 1 t big bags. The products are delivered to customers by railway and motor transport. Among the most large-scale modernization projects recently implemented is modernization of the closed circuit grinding system with installation of a separator in cement mills Nos. 6 and 7. Technical re-equipment of 6 kV switchgear of transformer substation No. 5 with replacement of high-voltage cells is in progress, the construction of cable overpasses is going on. An important event in 2022 was the commissioning of rotary kiln No. 4, which was shut down in 2010. The company received ISO 9001:2015 certification of its quality management system. АО Iskitimcement The capacity of the plant is 2.1 Mt of cement per year. Four wet process lines are in operation. Currently the plant offers 10 types of Portland cement, including: • standard cements: — CEM 042,5R; — CEM 042,5N; — CEM I 42,5N; — CEM I 52,5N; — CEM I 42,5R; — CEM II/A-Sh 32,5R; — CEM II/V-Sh 32,5N; • special purpose cements: — CEM I 42,5N DP; — CEM II/A-Sh 32,5R DO; — CEM I 42,5N AP. In 2022 AO Iskitimcement produced 1155 kt of cement. The main market for the product is the Novosibirsk region, supplies are also delivered to the Altai Territory and the Omsk region. Products are shipped in 25 and 50 kg paper bags (including those placed on pallets and packed in stretch film), in 1 t big bags and in bulk. Delivery is by road and rail. The plant operates a quality management system certified for compliance with the requirements of ISO 9001:2015. In 2022 a modern bag filter was installed behind the grate cooler of kiln No. 9. In addition, as part of the reconstruction of this kiln, the gas burner was replaced, and this allowed to reduce emissions of harmful substances into the air. It is planned to complete similar measures at process line No. 7 in 2023. The plant is also continuing to install an automatic emission monitoring system on the smokestacks of rotary kilns, which makes the information accessible to the general public online. The equipment is planned to be launched in 2024. In 2020 the plant began to ship separated cement, for which a separator was installed behind cement mill No. 6, and in 2022 the supply of such cement was close to 48% of the total volume of cement shipped. By the beginning of the 2024 construction season the plant expects to commission a separator at cement mill No. 5. Iskitimcement continues reconstruction of 3 kV electrical power lines switching to 6 kV voltage. Pre-project solutions are being drawn up for the reconstruction of the production facilities of the Loading shop. The work, planned for 9 years, is scheduled to be carried out in six stages: 1) reconstruction of the silo facility; 2) installation of bulk cement truck loading station at silos Nos. 1–20; 3) setting up a new loading section for cement in big bags with a large storage area; 4) reconstruction of the facilities for bulk cement loading into trucks from cement silos Nos. 21–24; 5) replacement of out-of-date packing machines Nos. 1 and 2 with further linking of all packing machines into a single transport system; 6) installation of a modern palletizer with automatic stacking of 50 and 25 kg paper bags on pallets and packing them in stretch film. The renovation of the Company's truck fleet is in progress. Today there are 28 cement trucks, 19 of them are new. In 2022 two tractor trucks and two bulldozers were purchased. Also, in 2022 a table X-ray fluorescent analyzer, a photoelectric photometer and a steam curing chamber were purchased. Angarskcement. Loading of cement in big bags into truck AO Iskitimcement. New baghouse OOO Krasnoyarsk Cement. Plant view

127 JANUARY—FEBRUARY 2023 OOO SLK Cement OOO SLK Cement is a part of Buzzi Unicem in Dyckerhoff Eastern Division and one of the leading producers of construction and oilwell cements in Russia. SLK Cement's facilities in Sukhoy Log, Sverdlovsk region (Sukholozhskcement), Korkino, Chelyabinsk region (Korkino) and Omsk produce construction, road and oilwell cement. In addition, the company includes a standalone transport company OOO CemTrans, which delivers construction cement to customers by road trucks. OOO SLK Cement holds a leading position in the Ural cement market and supplies its products to customers in other regions of Russia. The company has two terminals in Novosibirsk and one terminal each in Tyumen, Perm, Orenburg, Surgut and Nizhnevartovsk. Road cement is used to build highways and repair airports. The oilwell cement is fully compliant with international standards and is regularly delivered to the facilities of major oil and ООО Krasnoyarsk Cement The capacity of the plant is 1.1 Mt of cement per year, the products are produced using the wet technology, coal is used as a process fuel. Today the product range includes: • standard cements: — CEM 052,5N; — CEM 042,5N; — CEM I 42,5N; — CEM II/A­K (Sh-Z) 32,5R; — CEMENT II/A­Sh 32,5R; — CEM I 32,5R; • special cements: — PCT I­G­CC­1; — CEM I 42,5N SS NSch; — CEM I 42,5N DP; — CEM I 42,5N AP. The products are shipped by truck and railway in bulk, in 1000 kg big bags, also in 50 kg and 25 kg paper and polypropylene bags. In 2022 the company produced 634.8 kt of cement. In 2022 the construction of a 4 × 13.5 m closedcircuit cement mill (with a separator) with a capacity of up to 100 tons per hour was completed. The commissioning is scheduled for July 2023. Modern equipment capable of producing 60 tons of palletized cement per hour took the place of a semi-automatic palletizer with a capacity of 20 tons per hour. ООО TimlyuiCement The capacity of the plant is 800 kt of cement per year. Cement is produced by the wet method; a mixture of hard (long-flame and lean) coal is used as a process fuel. OOO TimlyuyCement. Plant view OOO Topkinsky Cement. Plant view Now the plant produces: • standard cements: — CEM II/A­Z 32,5N; — CEM I 42,5N; — CEM I 32,5N; — CEM 032,5N; — CEM 042,5N; • special cements: — CEM I 42,5N DP; — CEM I 42,5N SR NSch. The products are shipped by truck and railway, being delivered to customers in bulk, in 1,000 kg big bags and 50 kg paper bags. In 2022 the company produced 367.8 kt of cement. In 2022 two dump trucks, three tractor units, a dump truck, a forklift and other equipment were added to the plant's vehicle fleet. In 2022 the automation of raw material mills No. 2 and 5 of the Grinding Shop and rotary kilns No. 1 and 3 of the Burning Shop was finished at the facility. New modern control rooms were built in each of these departments. In 2022 technical re-equipment of the compressor department, which supplies production with compressed air, began in the Grinding shop. In December 2022 a new compressor with the capacity of 15,000 m3 of compressed air per hour was put into operation. It replaced the two units that had been in operation since the 1980s. OOO Topkinsky Cement The production capacity of the plant is 3.7 Mt of cement per year. The production method is wet, natural gas is used as process fuel. The company produces the following types of products: • standard cements: — CEM 052,5N; — CEM 042,5R; — CEM 042,5N; — CEM 032,5R; — CEM I 42,5R; — CEM I 42,5N; — CEM II/A­Sh 32,5R; — CEM II/V­Sh 32,5N; — CEM III/A 42,5N; • oilwell Portland cements: — PCT I­50; — PCT I­100; — PCT I­G­CC­1; • special types of cements: — CEM I 42,5N SS NSch; — CEM II/A­Sh 32,5R DO; — CEM I 42,5N DP; — CEM I 42,5N AP. In 2022, the plant produced more than 2.2 Mt of cement. The plant upgraded four electrostatic precipitators and is planning to upgrade another filter at rotary kiln No. 2. A closed circuit system is planned to be used at cement mills Nos. 5 and 6, after which Topkinsky Cement will be able to meet the growing market demand for high grade separated cement. In 2022 the company received 4 dump trucks with a capacity of 60 tons each, a heavy-duty truck, a bulldozer, 2 off-highway dump trucks and a crawler excavator. PR department AO HC SibCem RUSSIA Cement in big bags at Sukholozhskcement plant

128 JANUARY—FEBRUARY 2023 Vostokcement Crushed stone products are also produced at AO Teploozersky Cement Plant and AO PO Yakutcement. Vostokcement is an industrial group which produces construction materials on its in-house raw material base using the latest technologies, guided by the principle of production efficiency. This allows the company to be always confident in the quality of both raw materials and finished products. Vostokcement was founded in 1997 in Vladivostok. Today it unites all full cycle cement plants in the Far East — AO Spasskcement (Primorsky Krai/Maritime Territory, SpasskDalny), AO Teploozersky Cement Plant (Jewish Autonomous Region, Teploozersk) and AO PO Yakutcement (Sakha Republic (Yakutia), Mokhsogollokh). The combined cement capacity of these factories is 3.6 Mt. In 2022 cement plants of Vostokcement Group produced 3,141 kt of cement and 2,943 kt of clinker. In addition, the group includes aggregate plants — AO Vladivostok Stone and Aggregate Plant and AO Aggregate Processing Plant. Crushed stone products are also produced at AO Teploozersky Cement Plant and AO PO Yakutcement. In 2022, a branch of AO Spasskcement (cement grinding plant) was opened in YuzhnoSakhalinsk. The products of Vostokcement are supplied to the Republic of Sakha (Yakutia), Maritime, Khabarovsk and Kamchatka territories, Amur, Sakhalin, Magadan regions and the Jewish Autonomous Region. Today Vostokcement employs more than 5000 people. АО Spasskcement The factory was founded in 1907. Its production capacity is 2330 kt of cement per year. The plant produces Portland cement clinker, cement and mineral powder. The dry method of clinker production is used. The factory produces the following types of products: • general purpose cements: — CEM I 42,5N; — CEM II/A-P 32,5R; — CEM 052,5N; — CEM II/A-I 32.5R; — CEM I 42,5R; — CEM I 32,5R; • special cements: — PCT-I-50; — PCT-I-100; — PCT I G-CC-1; — CEM I 42,5N SR; — CEM I 42,5N AP; — CEM I 42,5N DP; — CEM I 42,5R ZhI; — CEM I 42,5N ZhI; • — Portland cement clinker; • — limestone meal; • — mineral powders. The production capacity of AO Spasskcement branch in Sakhalin is 100 kt of cement per year. In 2022 AO Spasskcement produced 1,970 kt of clinker and 2,479 kt of cement, which exceeded the capacity of the plant and became a record in the history of the Novospassky cement plant, including: • CEM I 42,5N — 1974 kt; • CEM II/A-P 32,5R and CEM II/A-I 32,5R — 69 kt; • special cements — 436 kt. 199 kt of cement were packaged in 50 kg bags and 1,054 kt of cement in 1,500 kg big bags. The Sakhalincement branch of AO Spasskcement produced 23 kt of CEM I 42,2N cement. 2 kt of cement were packaged in 50 kg bags. In 2022 a significant amount of work was carried out as part of modernization projects. Reliable operation of process equipment. The following projects have been or are in progress: • fans of Aerofol No. 1 and Aerofol No. 2 mills were replaced; • replacement of the sealing of the cold end of rotary kiln No. 2 was made. New graphite seal enables to reduce fuel consumption and to increase the kiln output; • at cement mills Nos. 1 and 2 the gears of the main drives were replaced; • the shell of the Aerofol mill No. 2 is scheduled to be replaced; • replacement of girth gear and pinions of the main drive of rotary kiln No.1 and complete replacement of the drive of rotary kiln No.2 are planned; • replacement of cement mill No. 2 shell has been performed. Improvement of process equipment efficiency. The following projects have been or are being implemented: • the rotary kiln exhaust gas sprinkler system on the 1st process line has been replaced; • bag filters of cement mill No. 2 and its separator have been replaced, and replacement of bag filters on four silos of cement batching plants is in progress; • preparation for replacement of the raw meal separator at the 2nd process line in order to increase the production capacity of raw meal is in progress; • the clinker cooler of rotary kiln No. 2 is being replaced. It is planned to carry out the reconstruction during the winter of 2023– 2024; • the project of replacement of the SMC separator of cement mill No. 2 with a new efficient separator is under way. The reconstruction is planned to be carried out in 2023. • weight batchers in cement mills Nos. 3 and 4 are replaced. Weighting equipment of cement mills is to be connected to the automated process control system of the plant; gas companies. Tyumen Region, Khanty-Mansiysk and Yamalo-Nenets Autonomous Districts are its main delivery areas. Some types of cement are exported; among the importing countries are Turkmenistan and Uzbekistan. In 2022, OOO SLK Cement produced 3,815,624 t of cement and 3,399,048 t of clinker. The Sukholozhskcement plant added Dylog-50, an oil-well cement with improved properties, to its portfolio. In 2022 OOO SLK Cement spent RUR 14 million on charity. N. Krasnova, PR specialist of OOO SLK-Cement AO Spasskcement. Plant view RUSSIA

129 JANUARY—FEBRUARY 2023 AO Spasskcement. New server room of the clinker burning shop Cement produced at AO Spasskcement branch in Sakhalin • the project of replacement of the heat shrinking machine of the cement palletizing line by the stretch hooding system is underway. АО Teploozersky Cement Plant AO Teploozersky Cement Plant, one of the largest industrial enterprises in the Jewish Au‑ tonomous Region, was founded in 1949. The plant produces clinker, cement, mineral powder and crushed stone. Raw materials are extracted from its own quarries. Annual production capacity of the company is 630 kt of cement and 850 kt of crushed stone. In 2022, AO Teploozersky Cement Plant produced 455 kt of clinker and 179 kt of cement, including: • CEM I 42,5N — 139 kt; • CEM II/A‑P 32,5R — 36 kt; • special cements — 4 kt. 11 kt of cement were packaged in 50 kg bags and 152 kt in 1,500 kg big bags. In 2022, during the repair of raw mill No. 3, its all-welded 13‑meter long shell, as well as the mill head and discharge covers, were replaced. After the body was replaced, the 2nd chamber of the mill was completely relined with rubber linings instead of metal ones. At the final stage of repair new plain bearings were mounted, linear and instrumental alignment of rotation axes and commissioning works were done. During the planned repair of the 1st kiln the chain curtain was modified — the carpet-type heat exchanger was replaced by free-floating chains. For the clinker burning shop three new weight batchers were purchased with the capacity up to 50 t/h and their control was optimized. Now a fiber optic cable is used to transmit information from the control desk to the weighers. A new compressor station was purchased which supplies compressed air to the pumping equipment in the clinker burning shop. The new compressor station consists of two compressors of the same capacity. Each of them has a capacity of 57 m3 of air per minute and is equipped with a refrigeration air dryer. The same compressors were also purchased for the raw materials shop. A new plate feeder was installed on the ham‑ mer crusher. For weight control of shipped products and raw materials extracted in the quarries of the company, motor-truck scales were purchased. The following three projects are currently underway: 1) reconstruction of the fuel preparation de‑ partment; 2) upgrading of cement mills No. 7 and No. 8 where the lining of the first and second cham‑ bers, chamber partitions and discharge lips will be replaced, a separation system will be installed to convert the mills to a closed-circuit operation and the newest weight batchers will be purchased and installed; 3) modernization of the packaging and ship‑ ment department, which will allow the simultane‑ ous use of two points of shipment and shipping cement in big bags to road and rail transport without delays. AO PO Yakutcement AO PO Yakutcement is the northernmost plant of Vostokcement Group commissioned in 1971. Today the company is the leader in the construc‑ tion industry of the Republic of Sakha (Yakutia). Yakutcement produces cement and crushed stone. The annual production capacity is 540 kt of cement and 812 kt of crushed stone. In 2022 AO PO Yakutcement produced 518 kt of clinker and 460 kt of cement, including: • CEM I 42,5N — 283 kt; • CEM I 32,5R — 117 kt; • special cements — 59 kt. 9 kt of cement were packaged in 50 kg bags and 307 kt in 1,500 and 1,000 kg big-bags. The following measures were put into prac‑ tice in 2022: • in the Burning department, owing to technolo‑ gical solutions related to the burning regime and optimization of the chain curtain in March 2022, the hourly capacity of rotary kiln No. 3 was in‑ creased from 22.5 (design value) to 26 t/h; • in the Grinding Department: — the gearbox of raw mill No. 3, which has dimensions of Ø 2,6 × 13, was installed and an additional water heating system for clay preparation was installed; Тel.: +7 (812) 242-1124. E-mail: [email protected] ИЮЛЬ—АВГУСТ 2014 97 УДК 658.114.4:666.94 Е. Смирнова, ООО «Красноярский цемент», Россия РЕФЕРАТ. В октябре 2014 года Красноярскому цементному заводу  исполняется 70 лет. Все эти годы предприятие работало, обеспечивая сибирские стройки цементом. Вместе со страной оно  переживало трудные времена, экономические спады и подъемы,  перестройку системы взаимодействия с потребителями продукции. Сегодня «Красноярский цемент» является дочерним обществом одного из крупнейших холдингов отрасли  – «Сибирского  цемента». В его составе завод в течение 10 лет стабильно работает, эффективно используя накопленный опыт и производственную базу. Предприятие осваивает выпуск новых видов продукции, повышает производительность оборудования, увеличивает  свои производственные мощности. Ключевые слова: производство цемента, гидротехнический цемент, тампонажный цемент. Ключевые слова: cement production, hydrotechnic cement, oil-well cement. В 30-е годы прошлого столетия развитию производства в восточных районах страны уделялось особое внимание. Так, план третьей пятилетки предусма - тривал создание в Сибири целого ряда промышленных объектов, в том числе предприятий цементной отрасли. Для строительства Красноярского цементного завода выбрали территорию на правом берегу Енисея в районе с. Торгашина. В качестве сырья для производства строительного материала решено было использовать известняки Торгашинского месторождения и глины, залежи которых находились между участком известняка и селом. Оборудование, смонтированное впоследствии на трех технологических линиях предприятия, поступило в Красноярск с эвакуированного в начале войны НиКрасноярский цементный завод был введен в эксплуатацию в 1944 году. Этому событию предшествовала огромная работа, выполненная проектировщиками, геологами, монтажниками и строителями. Красноярский цементный завод отмечает юбилей репринт из журнала «Цемент и его применение» №4 • 2014 Cement and its Applications март—апрель 2013 91 УДК 621.927.4:621.926.8:662.66 Работа угольной вертикальной валковой мельницы на заводе в Бельгии Д-р К. Войвадт, руководитель технологического отдела, Р. Зоннен, руководитель отдела выполнения заказов, Gebr. Pfeiffer SE, Германия РЕФЕРАТ. Описана работа угольной вертикальной валковой мельницы MPS 225 BK, разработанной немецкой компанией Gebr. Pfeiffer SE, на заводе компании CBR, входящей в группу HeidelbergCement, в Ликсе (Бельгия). Приведена технологическая схема установки помола угля. Согласно результатам испытаний в условиях эксплуатации, новая установка полностью отвечает требованиям по производительности и рабочим параметрам. Ключевые слова: вертикальная валковая мельница, помол угля, установка для помола и сушки. Keywords: vertical roller mill, coal grinding, grinding-drying system. 1. Введение Вертикальные валковые мельницы MPS и MVR, разработанные компанией Gebr. Pfeiffer SE, применяются для помола цементного сырья, клинкера и гранулированного доменного шлака во многих странах мира. Мельницы MPS используются также для одновременного измельчения и сушки различных типов угля (антрацита, каменного или бурого угля), а также различных видов нефтяного кокса на многочисленных цементных, металлургических заводах и электростанциях. В данной статье приведено общее описание угольных мельниц Gebr. Pfeiffer SE и описан ход работ на мельнице MPS 225 BK, установленной для компании CBR Lixhe (Бельгия). 2. Конструктивные особенности и преимущества мельницы В цементной промышленности в большинстве установок для помола угля используются два типа мельниц. Это вертикальные валковые мельницы, доля использования которых достигла почти 90 %, и шаровые мельницы, доля использования которых сократилась и составляет немногим более 10 % [1]. Компания Gebr. Pfeiffer SE поставляет автономные угольные мельницы MPS, а также комплексы для помола и сушки угля. Мельницы и помольные комплексы могут работать под давлением или при разрежении, в воздушной атмосфере или атмосфере инертного газа. В поставку могут входить помольные установки с временным хранением пылевидного угля в бункерах (на цементных и сталеплавильных заводах и т. д.) и установки с его прямым впрыском в камеру сжигания (на электростанциях). На рис. 1 приведены основные параметры угольных мельниц серии MPS. В зависимости от вида измельчаемого топлива при производительности от 5 до 200 т/ч можно достичь тонины помола от 1 % R 0,063 мм до 25 % R 0,090 мм. Мельница MPS для помола угля с возможностью его одновременной сушки позволяет молоть бурые угли с исходной влажностью до 45 %. При высокой влажности сырья технические характеристики мельницы в большей степени определяются необходимостью сушки сырья в мельнице, а при помоле антрацита, тощего каменного угля и нефтяного кокса — необходимостью измельчать их до заданной дисперсности. Различные характеристики твердых видов топлива, такие как размалываемость, содержание золы, летучих веществ, а также необходимая тонина помола, требуют широкого разнообразия возможных рабочих состояний мельницы. Гидравлическая система плавно регулирует усилие, прикладываемое валками, обеспечивая помол различных видов твердого топлива. С учетом варьирования расхода воздуха диапазон регулирования параметров работы мельницы составляет от 30 до 100 %. При изменении необходимой загрузки мельниц с впрыском, установленных на электростанциях, или при отличии качества топлива и его размалываемости от указанных в проекте возможна эксплуатация мельницы с частичной загрузкой. Вертикальная валковая мельница MPS представляет собой статическую систему, состоящую из прижимной рамы, трех валков и трех наружных тяг, и обеспечивает равномерное распределение нагрузки на помольный стол, который приводится в действие с помощью электродвигателя и редуктора. Во время запуска и технического обслуживания подъем валков выполняется с помощью натяжных цилиндров. Высокоэффективный воздушный сепаратор типа SLS смонтирован над зоной измельчения. В этой же зоне находится устройство для загрузки исходного материала, который здесь же смешивается с крупкой, удаленной из сепаратора (рис. 2). Основное отличие мельницы MPS для твердых видов топлива от других мельниц MPS состоит в устойчивости к воздействию ударной волны. Корпус мельницы и воздушного сепаратора, загрузочное устройство и компенсаторы имеют ударопрочную конструкцию, обеспечивающую безопасность при возникновении ударной волны. Во избежание скопления угольной пыли, являющейся источником самовоспламенения, все поверхности в зоне измельчения и сепарации расположены вертикально или с наклоном. Перечислим основные отличительные особенности установок для помола угля на цементных заводах: • специальная схема расположения установки, необходимая для того, чтобы исключить отложения угольной пыли; • ударопрочная конструкция корпуса мельницы и воздушного сепаратора, фильтра и бункеров для угольной пыли; репринт из журнала «Цемент и его применение» №2 • 2013 Cement and its Applications МАРТ—АПРЕЛЬ 2014 101 УДК 621.822.8: 666.9 Разъемные подшипники для цементной промышленности А.В. Головкин, заместитель руководителя индустриального отдела, ООО «Шэффлер Руссланд», Россия РЕФЕРАТ. Плановые и аварийные работы по замене подшипников  приводят к длительным простоям оборудования в связи с большой трудоемкостью сопутствующих технологических операций.  Применение разъемных подшипников позволяет в несколько  раз сократить время проведения этих работ. В статье описаны  устройство и преимущества разъемных подшипников FAG, выпускаемых немецкой компанией Schaeffler, даны рекомендации  по их использованию в оборудовании цементной промышленности и приведен пример их успешной эксплуатации на цементном  заводе в Испании. Показано, что в результате замены неразъемных подшипников на разъемные достигается значительный  экономический эффект. Ключевые слова: разъемные сферические роликоподшипники, запасные части, демонтаж. Keywords: split spherical roller bearings, repair parts, disassembling. состоят из разъемного внутреннего кольца, разъемного сепаратора (изготовленного из стеклонаполненного полиамида или латуни) с роликами, а также разъемного наружного кольца. Половины колец соединяются между собой прецизионными и стяжными винтами (рис. 1). В соответствии с производственной программой выпускаются разъемные сферические роликоподшипники для валов, имеющих диаметр от 55 до 630 мм и от 2 3/16 до 16 дюймов. Рассмотрим основные этапы замены стандартного подшипника на разъемный без полного разбора конструкции. Вначале необходимо подвести опору под вал-ротор и снять крышку корпуса. Старый неразъемный подшипник вместе с втулкой осторожно распиливают разрезным кругом и демонтируют. Затем наружное полукольцо разъемного подшипника помещают в нижнюю часть корпуса, а смонтированное внутреннее кольцо — на вал. Затем центрируются и скрепляются половинки внутреннего кольца. После монтажа остальных деталей затягиваются винты, скрепляющие половинки наружного кольца. Далее вал освобождается от опоры, и крышка корпуса устанавливается на место. Число операций, выполняемых при монтаже разъемных подшипников, меньше, чем при монтаже неразъемных (см. таблицу). Хотя стоимость разъемного подшипника в 1,5—2 раза выше, чем неразъемного (с учетом необходимости приобретения закрепительной втулки для неразъемного подшипника), значительный экономический эффект достигается за счет снижения трудоемкости и времени работ по замене вышедшего из строя подшипника. Затраты и потери, связанные с простоем оборудования, снижаются главным образом благодаря сокращению его продолжительности, которое приводит к уменьшению упущенной выгоды (рис. 2). Инновации и оптимизация себестоимости продукции являются важными рычагами повышения эффективности производства. Разъемные подшипники качения — это одно из средств, позволяющих повысить его эффективность. Известно, что совокупная стоимость владения оборудованием складывается из всех затрат и издержек (в том числе связанных с простоями по причине ремонта), возникающих при эксплуатации оборудования. Более высокие затраты на начальном этапе, выраженные в повышенной стоимости разъемного подшипника, приводят в дальнейшем к существенной экономии. Экономия же на подшипнике, напротив, ведет к возникновению серьезных затрат в будущем. Замена подшипника зачастую сопряжена с демонтажом сопряженных деталей. В крупных механизмах, если доступ к подшипнику затруднен, требуются большие затраты времени и сил на демонтаж близлежащих деталей, таких как муфты, валы привода, зубчатые колеса, корпуса, крыльчатки, барабаны и др. Как правило, взамен неразъемных сферических роликоподшипников с закрепительной втулкой могут быть установлены разъемные. Условием возможности такой замены является равенство наружного диаметра, ширины наружного кольца и посадочного диаметра на вал у неразъемного и у разъемного подшипников. Основное отличие разъемного сферического роликоподшипника от стандартного — ширина внутреннего кольца примерно вдвое больше, поэтому требуется предусмотреть большее посадочное пространство под внутреннее кольцо. Разъемные сферические роликоподшипники выпускаются с нормальными допусками и с нормальным зазором, которые соответствуют нормальным допускам и нормальному зазору неразъемных радиальных сферических роликоподшипников с цилиндрическим отверстием (в соответствии с DIN 620), благодаря чему не нужно переделывать конструкцию сопряженных деталей — вала и корпуса. Разъемные сферические роликоподшипники репринт из журнала «Цемент и его применение» №2 • 2014 Cement and its Applications май—июнь 2011 119 репринт из журнала «Цемент и его применение» №3 • 2011 Cement and its Applications УДК 628.511.4:666.9 Опыт использования высокоэффективных фильтровальных рукавов Компания BWF Envirotec (Германия) занимает лидирующее положение на мировом рынке нетканых фильтровальных материалов, производимых из всех типов синтетических волокон. Компания предлагает широкий выбор фильтровального материала, фильтровальные элементы всех типов и конструкций, запасные части для пылеулавливающего оборудования, а также монтаж и демонтаж рукавных фильтров у заказчика. BWF Envirotec дает рекомендации по выбору фильтровального материала, производит лабораторные исследования рукавных фильтров и пыли, моделирует в собственной лаборатории условия различных процессов газоочистки, максимально приближенные к реальным условиям применения. В минувшем десятилетии произошли серьезные изменения в области очистки промышленных газов в цементной промышленности. Законы об охране окружающей среды, касающиеся отрасли, становятся все более жесткими, поэтому цементные завоЭ. Ронер, директор по технологии и применению, BWF Tec GmbH & Co. KG, Германия, Д.И. Кузнецов, генеральный директор, ООО «БВФ Энвиротек», Россия РефеРат. В статье отражены результаты деятельности фирмы BWF Envirotec, специализирующейся на системах газоочистки в цементной промышленности — разработке и поставке рукавных фильтров, изготовленных на основе различных фильтровальных материалов. Дана оценка физико-химических, механических свойств этих материалов и показаны принципы их выбора для конкретных условий эксплуатации. Приводятся технические характеристики оборудования, поставленного фирмой на ряд цементных заводов в странах Европы и Азии. Показана его эффективность и надежность. Ключевые слова: рукавный фильтр, фильтровальный материал, газоочистка, пыль, гидролиз, химическая устойчивость, обработка, механическое воздействие. Key words: bag filter, filter materials, gas purification, dust, hydrolysis, chemical resistance, finishe, mechanical impact. ды вынуждены постоянно снижать выбросы пыли. Чтобы соблюдать эти строгие правила, отходящие газы от ленточных конвейеров, мельниц, клинкерных холодильников и печей обжига необходимо очищать с высочайшей эффективностью. Для выполнения указанных задач BWF Envirotec предлагает широкий выбор высококачественных рукавных фильтров. фильтровальные материалы Фильтровальные материалы компании BWF Envirotec производятся из синтетических волокон. В большинстве случаев эти материалы изготавливаются на поддерживающем каркасе, который увеличивает их механическую прочность (рис. 1). Каждый тип волокна обладает уникальными термическими, механическими и химическими характеристиками, которые важны для эффективности и срока службы фильтровального рукава. Возможности же комбинации различных типов каркаса и набивки фильтровального материала почти безграничны. Выбор наиболее подходящего сочетания зависит в первую очередь от назначения, а также от экономических показателей. За последние годы на цементных заводах доказали свою пригодность типы фильтровальных материалов, приведенные в табл. 1. Среди технических характеристик (табл. 1) указаны рабочая и максимально допустимая температуры использования фильтровального материала. Однако они представляют максимально возможный предел температуры в идеальных лабораторных условиях и должны рассматриваться лишь как характеристики данного полимера. В реальных условиях химические реакции с опасными компонентами отходящих газов и пыли вынуждают применять все полимеры (кроме РТFЕ) при более низких температурах. типы фильтровальных материалов, используемых на цементных заводах Гомополимер полиакрилонитрила (Dт) Описание. Полиакрилонитрил, как фильтрующий материал, устойчив к окислению и гидролитическому воздействию. Рабочая температура ограничена 125 °С, возможны кратковременные подъемы темРис. 1. Поперечный разрез фильтровального материала набивка Поддерживающий каркас СЕНТЯБРЬ—ОКТЯБРЬ 2015 81 Департамент по связям с общественностью ОАО «ХК «Сибцем» РЕФЕРАТ. В статье описана история Топкинского цементного завода, входящего в состав холдинговой компании «Сибирский  цемент». Приведены сведения о масштабных мероприятиях по  модернизации производства, проводящихся на предприятии  в течение последнего десятилетия. Дана информация об ассортименте продукции и направлениях ее использования. Ключевые слова: цементный завод, производство, модернизация. Keywords: cement plant, production, modernization. преимущество — стабильно высокое качество выпускаемых строительных материалов. От проекта — к производству Топкинский цементный завод вошел в число действующих предприятий страны 30 января 1966 года. В этот день государственная комиссия приняла в эксплуатацию технологическую линию № 1. Однако история «Топкинского цемента» началась на 20 лет раньше — именно столько времени потребовалось для оформления проектной документации, подготовки и ведения строительных работ. В послевоенном 1946 году в Топкинском районе Кемеровской обл. была проведена предварительная геологическая В январе 2016 года Топкинскому цементному заводу исполнится 50 лет. С 1966 по по ноябрь 2015 года на нем выпущено 99 084 653 тонны цемента. В истории предприятия были разные этапы: на смену периодам становления и динамичного развития пришел спад 1990-х, который затем уступил место мощному подъему 2000-х. Сегодня промышленный гигант в составе холдинговой компании «Сибирский цемент» входит в число лидеров цементной индустрии Сибири. Топкинские цементники ведут модернизацию оборудования, расширяют ассортимент продукции, сохраняя при этом свое главное конкурентное репринт из журнала «Цемент и его применение» №5 • 2015 Cement and its Applications УДК 658.114.4:666.94 Юбилей Топкинского цементного завода and translated articles from us You can order reprints

130 JANUARY—FEBRUARY 2023 AO Teploozersk Cement Plant. Rotary kilns AO PO Yakutcement. Packed cement OOO Aluminate Cement Plant In 2022 the company produced 463 t of cement, including: • VGC-60 — 230 t, • VGC-70 — 154 t, • GC-35 40 — 55 t, • GC-35 50 — 24 t. 462 t of cement in 40 kg bags were shipped by road. According to information of OOO Aluminate Cement Plant RUSSIA — the cement mill: grinding intensifiers were selected and their permanent application was started; • 3 additional compressors were installed and started up; — in the Crushing department flowcharts for the production of crushed stone for road construction in accordance with GOST 32703–2014 were worked out and approved for production, and 5 types of crushed stone with different grain-size composition were put on the market; • in the field of environmental protection: — a FTOR filter was installed at mill No. 4; — pre-design work on reconstruction of ESPs of rotary kilns Nos. 1 and 2 was started. The company began to work on the program of modernization and replacement of equipment in the short term until 2026, which includes the following: • for the Burning Department: — reconstruction of the cold end seal of rotary kiln No. 3 to improve its technical performance; — design and installation of a clinker conveyor with unloading to the pier; — modernization of the belt clinker conveyor with splitting it into two conveyors operated separately; — replacement of the overhead grapple crane with capacity of 10 t and the gantry crane with capacity of 4 × 12,5 t; — automation of the clinker burning process in rotary kilns No. 1 and 2; • for the "Grinding" department: — replacement of the shell of mill No. 5; — modernization of the belt sifting conveyor; — automation of the grinding process in raw mills and compressor equipment operation; — reconstruction of the transformer substation of the cement grinding department TP-26/0,4 kV with total maximum capacity of 9 MW; • purchase of a new carousel packing machine to replace the existing one; • in the Crushing department — purchase of a new screen to replace the existing one; • replacement of high-voltage transformers; • fleet renewal — purchase of the following equipment: — dump trucks; — a bulldozer; — a forklift; • ongoing reconstruction of electric precipitators of rotary kilns No. 1 and 2; • reconstruction of crushed stone weighing building with installation of new weighing equipment. The development of a new semi-dry production method is actively underway at the Teploozersk Cement Plant and Yakutcement. More detailed information about this is planned to be published in the future in the journal Cement and Its Applications. In addition to cement, Vostokcement produces crushed stone, ready-mixed concrete, asphalt and dry building mortars in Vladivostok. The capacity of crushed stone plants is 1.8 Mta, concrete — 350 m3/h, asphalt — 310 tph, dry building mortars — 60 kt per year. According to UK Vostokcement OOO Asia Cement OOO Asia Cement plant in the Penza region (Volga Federal District). with the production capacity of 1860 kt per year produces cement with high strength characteristics and stable quality parameters using the dry method. In 2022 the plant produced 1771 kt of cement, including 247.6 kt of bagged cement. The product line of Asia Cement comprises the following types of cement: • bulk: — CEM 052,5N; — CEM I 42,5N; — CEM II/A-P 42,5N; — CEM II/A-P 32,5N; • bagged: — CEM I 42,5N; — CEM II/A-P 42,5N; — CEM II/A-P 32,5N. In addition, in 2022 an innovative product for road construction — micropor (a mineral binder) was released to the market. In 2023 OOO Asia Cement received a certificate for producing a new cement brand CEM I 52,5N ZhI GOST 55224–2020. Regions of presence of OOO Asia Cement are the Penza, Ulyanovsk, Nizhny Novgorod, Samara, Vladimir, Kirov, Ivanovo, Tambov, Lipetsk, Moscow, Yaroslavl regions, as well as the Republics of Mari El, Mordovia, Tatarstan and Chuvashia. At the beginning of 2022 OOO Asia Cement was the first among Russian cement plants to receive the status of a "green" operation. The company uses alternative fuels. The share of cement with additives in the total sales of the company in 2023 should reach 40%. Press Service of OOO Asia Cement RUSSIA Control panel of the burning shop

131 JANUARY—FEBRUARY 2023 OOO Cemix The white cement plant with the annual production capacity of 250 kt was commissioned in August 2021. The plant produces two brands of high-quality white cement Cemix ProWhite: • PCB 1–500-D0, • PCB 1–500-D20. The geography of supplies is the whole territory of the Russian Federation, as well as Kazakhstan and Belarus. The leading consumers of white cement in Russia note a stable high quality of produced white cement. The logistics chains have been adjusted; two terminals for transshipment of white cement and storage of bagged products have been launched for the convenience of the company's clients: Moscow (Lukhovitsy) and Yuzhny (Afipsky, Krasnodar Territory). In 2023, the company plans to increase the volume of white cement production, as well as to enter new markets in Central Asia. N. O. Soskov, Sales and Marketing Director ATOM Cement plant ATOM Cement plant is a part of Atomstroycomplex which built it from scratch. Production began there in 2021. In 2022 the facility reached its design capacity. About 450 kt of cement was shipped during the year, and a sufficient stock of clinker is maintained in the storage at all times. The company in 2022 focused on establishing a client pool: on the basis of its own laboratory it was developing a concrete formulation for the majority of potential consumers. Now the largest concrete producers of the Sverdlovsk Region work with the plant's cement. Atomstroycomplex plans to further develop the production site where, apart from the ATOM Cement plant, a lime production plant is already located. Options for the second stage of the cement production are under consideration as well as the construction of a plant to produce gas and cinder blocks. E.A. Glyzin, CEO of the ATOM Cement plant RUSSIA Plant view AO Bakhchisaray Stroyindustriya Combined Works In 2022 the company produced 324.9 kt of clinker and 369.6 kt of cement of general construction types, including: • CEM 052.5 N — 170.8 kt; • CEM I 52.5 N — 113.7 kt; • CEM I 42.5 N — 52.6 kt; • CEM II/A-L 42.5 N — 32.5 kt. 14.1 kt of cement were packed in 25-kg bags. 370.5 kt of cement were shipped by road. According to information of Bakhchisaray Stroyindustriya Combined Works RUSSIA RUSSIA OOO Cemix. Plant view AO Chechencement The company's products, Portland cement CEM I 42,5N, are mainly supplied to consumers in the Chechen Republic, but are also bought by customers from adjacent regions. In 2022, the plant produced 673.6 kt of clinker and 679.3 kt of cement. 676.8 kt of cement was shipped by truck, including 79.6 kt of bagged cement, including: • in one-ton big-bags — 66.6 kt, RUSSIA

132 JANUARY—FEBRUARY 2023 OOO Magnitogorsk Cement and Refractory Plant (MCOZ) The production capacity of the plant is 930 kt of cement per year. In 2022426.9 kt of clinker and 426.3 kt of ce‑ ment were produced, of this amount: • CEM I 42,5N — 320.5 kt; • CEM II/A‑Sh 32,5N — 58.6 kt; • CEM II/V‑Sh 32,5N — 47.2 kt. Bagged cement: • in bags, including on pallets and semi-pal‑ lets — 59.9 kt; • in 1t big bags — 20.7 kt. 13.9 kt of clinker and 425.3 kt of cement were shipped, of that amount — by types of transport • by motor transport — 337,7 kt; • by rail — 87.5 kt. The company produced 416.2 kt of lime-mag‑ nesia and magnesia-calcinated flux and 55.8 kt of ferruginized lime. In 2022 the transportation and shipping department of the plant was equipped with telescopic loading devices of a new type for bulk cement loading in order to avoid loss of cement due to dusting during loading into hop‑ pers, and to improve working conditions of the personnel due to elimination of dust pollution. In order to increase shipments in 2023 it is planned to improve the outdated equipment through the project "Cement shipment process line. Big Bag filling plant". Yu.N. Kochubeyev, CEO of OOO MCOZ RUSSIA Plant view • in 50 kg bags — 13.0 kt. In 2019, the 1st stage of the plant modernization project was completed, which included the con‑ struction of a cement grinding shop with a capac‑ ity of 100 t of cement per hour, a clinker silo with a capacity of 60 kt and 2 cement silos of 10 kt each. The following is planned for the 2nd stage of modernization: • construction of a dry process cement production line with a capacity of 1 Mt of clinker per year, • upgrading of the raw materials department, • construction of an additional grinding shop with a capacity of 100 tons of cement per hour, • construction of a crushing plant with a capacity of 1,000 t/h, • construction of a power center (a section for inhouse generation of electric power produced by gas-turbine engines). At present, commissioning of a newly built lime‑ stone crushing plant with a capacity of 1,000 t/h, located in the quarry owned by AO Chechen­­cement, is underway at the expense of the com‑ pany's own funds. Sh.Sh. Dudayev, General Director Plant view The cement plant of OOO Norilsk Support Complex The cement plant of OOO Norilsk Sup‑ port Complex (Norilskiy Obespechivayushchiy Kompleks) is located in Norilsk, Krasnoyarsk region. In 2022 the following amount of cement was produced: • CEM 0 32,5N — 117.8 kt; • CEM I 32,5N — 485.4 kt. In 2022 in the clinker burning shop electrostatic precipitator No.2 EFSG 1–30–7,5–3-4,48 was replaced on the rotary kiln of 5 × 185 m size. According to information of the cement plant of OOO Norilsk Support Complex RUSSIA AO Sebryakovcement The Sebryakov Cement Plant is one of the leading producers of building materials in Russia. The factory was put into operation in 1953. The new era in the history of Sebryakovcement began with the development and subsequent implemen‑ tation of a plan of large-scale reconstruction and modernization of the facility, including complex and costly projects. Since 2002 the founders of the AO Sebryakovcement have allocated more than RUR 20 billion for the development of the company in different spheres. And it is no less im‑ portant that all the funds were not borrowed but received as a result of daily coordinated work of the whole plant's team. The product range includes the following cements: • according to GOST 31108–2020: — CEM I 42,5N; — CEM 042,5N; — CEM II/A‑Sh 42,5N; — CEM I 32,5R; • according to GOST 33174–2014 — CEM I 42,5N DP; • according to GOST R 55224–2020 — CEM I 42,5N ZhI; RUSSIA

133 JANUARY—FEBRUARY 2023 • according to GOST 22266–2013 — CEM II/ A‑Sh 42,5N SR. The company keeps the quality of its products at the highest level. In 2022, the geography of AO Sebryakovce‑ ment's product deliveries included: • the republics — Adygea, Bashkortostan, Dage‑ stan, Ingushetia, Kabardino-Balkaria, Kalmykia, Karelia, Crimea, North Ossetia, Chechen Republic; • the territories — Krasnodar, Perm, and Stavropol; • the regions — Arkhangelsk, Astrakhan, Belgorod, Bryansk, Vladimir, Volgograd, Vologda, Voro‑ nezh, Ivanovo, Kaluga, Kostroma, Kursk, Lenin‑ grad, Moscow, Nizhny Novgorod, Orenburg, Plant view Orel, Penza, Pskov, Rostov, Ryazan, Samara, Saratov, Tambov, Tula, Chelyabinsk, Yaroslavl; • the cities — Moscow, St. Petersburg, Sev‑ astopol. In 2022 the company produced 2,322.7 kt of clinker and 2,565.0 kt of cement, including: • CEM II/A-Sh 42.5N — 963.7 kt; • CEM 0 42.5N — 721.8 kt; • CEM I 42,5N — 556.2 kt; • CEM II/A-Sh 42.5N SR — 160.0 kt; • CEM I 32.5B — 144.2 kt (of this amount for as‑ bestos-cement products manufacturing — 144.0 kt); • CEM I 42,5N DP — 19.1 kt. 738.7 kt of cement were bagged, of which: • in bags — 369.5 kt; • on pallets — 261.1 kt; • in big bags — 108.1 kt. 2,561.2 kt of cement were shipped, of this amount: • by rail — 1,500.3 kt; • ex works — 917.5 kt; • by pneumatic transport — 143.4 kt. AO Sebryakovcement's plans include further activities within the framework of the renewal of the main process equipment, which has already begun. It was decided to reconstruct process line No. 8 of the combined method of cement clinker production switching it to a dry, energy-saving pro‑ duction method and fitting it with up-to-date process equipment. In particular, it is planned to install a dy‑ namic separator to ensure optimal raw meal grinding fineness and a system of selective non-catalytic reduction of nitrogen oxides, to replace the ESP with a modern bag filter, to change entirely the rotary kiln control and monitoring system and to move its control panel to the central control room where the dry method kiln control systems are located. Among the new projects, there are also construction of a 4.6 × 14 m cement mill No. 14, which will work in a closed cycle together with the clinker pre-grinder, and installation of an automatic system for monitoring of industrial emissions at the plant. The plant is studying the experience of using alternative fuels for clinker burning. The activities carried out as part of the technical upgrading program will enable the plant to main‑ tain its position as one of the leaders in Russia's cement industry, supplying high quality products. S.P. Rogachev, General Director AO Sebryakovcement According to the State Statistical Commitee of the Republic of Azerbaijan, cement pro‑ duction in the country in 2022 increased by 3.5 % (to 3,558,1 kt) as compared to 2021, production of precast concrete structures and parts increased by 1.1 % (to 47.5 thou. m3). The average price of cement increased by 6.1 %, up to 8.63 AZN per 50 kg (the average exchange rate in 2022 was 40.3 RUB for 1 AZN). The total area of residential buildings commissioned in 2022 increased by 24.8 % (up to 2,592.9 thou. m2). In Baku, it increased by 53.9 % (to 1,120.1 thou. m2), in the Nakhchivan Autonomous Republic it decreased by 3.7 % (down to 376.1 thou. m2). AZERBAIJAN There are two integrated cement plants operating in the country: ZAO Araratcement and OOO Hrazdan Cement Corporation. According to the National Statistical Service of the Republic of Armenia, in 2022 cement production in the country increased by 17.7% (up to 1,004.1 kt) as compared to 2021, production of precast concrete structures and parts decreased by 20% (down to 84.3 kt). 180.6 kt of cement worth about US$ 8,1 million were imported into the country. In 2022 investments in construction works increased by 12.5 %, to AMD 541.1 bil­lion (the average exchange rate in 2022 was 100 AMD for nearly 15.64 RUB). The gross floor area of residential buildings commissioned increased by 17.9 %, to 322.2 thou. m2, of which 147.5 thou. m2 were commissioned in Yerevan. ARMENIA OOO Hrazdan Cement Corporation The Hrazdan Cement Plant has 2 rotary kilns, its design capacity for clinker is about 1,100 kt per year. The number of employees is about 400 people. In 2022, OOO Hrazdan Cement Corporation produced 136.3 kt of clinker and 151.8 kt of cement, including: • CEM I 52.5N — 29.2 kt; • CEM II B‑P — 122.6 kt. The plan is to produce between 250 kt and 300 kt of cement and at least 200 kt of clinker in 2023. S.V. Mazmanyan, Cand. Tech. Sc., Head of Labora‑ tory and Quality Manager ARMENIA The company's bagged products

134 JANUARY—FEBRUARY 2023 Norm Sement In 2022 the company produced 1,460.9 kt of clinker and 1,546.7 kt of cement, including: CEM II/A-P 42.5 R — 548.8 kt; CEM II/A-P 32.5 R — 543.1 kt; CEM II/B-L 32.5 R — 210.1 kt; other cements — 196.4 kt. 773.3 kt of cement were bagged: 770.6 kt in bags and 2.7 kt in big bags. Shipped to the customers: 354.7 kt of clinker and 1,557.0 kt of cement by road. According to Norm Sement AZERBAIJAN BELARUS There are three integrated cement plants operating in the country, which are part of the Belarusian Cement Holding Company: ОАО Belarusian cement plant, ОАО Krasnoselskstroymaterialy and ОАО Krichevcementnoshifer. According to OAO Belarus Universal Commodity Exchange (BUTB), in Q4 2022 the volume of transactions concluded following the results of session exchange trading in cement on the domestic market amounted to 201.5 kt. Thus, about 25% of all cement produced in the Republic of Belarus passed through the BUTB. The total volume of sales of these products at the BUTB in 2022 amounted to 531.6 kt that is 3.5 times more than in 2021. According to the Committee on National Statistics of the Republic of Belarus, producers' price indices in 2022 amounted to 117.5% for cement and 114.7% for precast constructions and parts. In 2022 fixed investments in construction decreased by 19% down to 27.8 billion Belarusian rouble (in comparable prices) as compared to 2021.The scope of contract work in construction decreased by 11.9%, down to BYN 13.4 billion. The cost of residential housing construction amounted to BYN 6.3 billion. The average exchange rate of Bank of Russia in 2022 was 1 BYN to 25.9 RUB. The amount of residential housing commissioned in Belarus decreased by 3.7 % (to 4,226.2 thou. m2), in Minsk city — by 7.4 % (to 891.0 thou. m2). The area of buildings commissioned by individual developers increased by 2.6% (to 2,471.7 thou. m2). KAZAKHSTAN The data on production of cement clinkers and Portland cement in the Republic of Kazakhstan and its regions in 2022 (according to Statistics Committee of the Republic of Kazakhstan data) is shown in table 1. In 2022 20,225.4 kt of ready-mixed concrete and 1,022.2 kt of precast concrete structures and parts were produced in the country. In 2022 the country exported 1,053.3 kt of cement worth about US$ 54.7 million. The country's imports amounted to 853.4 kt of cement for the sum about US$ 52.5 million. The data on export and import of cement in the Republic of Kazakhstan in 2022 is shown in tables 2 and 3. In October, November and December 2022 average producers' prices in the domestic market amounted to KZT 22,797; 22,855 and 22,803 per tonne of cement and KZT 8,914; 8,937 and 8,931 per qubic meter of ready-mixed concrete, respectively. Table 1 Production of cement clinkers and Portland cement, kt Area Cement clinkers Portland cement Republic of Kazakhstan 8 289,0 12 088,3 Akmola oblast No data No data East Kazakhstan oblast 901,9 968,9 Zhambyl oblast No data No data Karaganda oblast No data 1 665,7 Kyzylorda oblast No data 1 119,9 Mangistau oblast No data 944,2 Shymkent city 2 580,9 2 902,0 Table 2 Cement export of Kazakhstan Country 2022 2021 kt thou. US$ kt thou. US$ Uzbekistan 593,1 26 376 1 079,7 54 867 Russia 213,2 16 219 234,2 13 463 Kyrgyzstan 246,2 11 758 287,6 13 399 Others 0,8 301 0,7 127 Total 1 053,3 54 654 1 602,2 81 856 Table 3 Cement import of Kazakhstan Country 2022 2021 kt thou. US$ kt thou. US$ Russia 662,8 42 774 942,3 54 214 Iran 187,2 7 493 147,8 5 687 Others 3,4 2 231 3,6 938 Total 853,4 52 498 1 093,7 60 839 Table 4 The cost of housing construction Area In mln tenge* as percentage to 2021 level Republic of Kazakhstan 2 296 345 101,2 Aktobe oblast 119 728 108.9 Almaty oblast 128 647 119,5 Mangistau oblast 112 084 115,3 City of Astana 427 504 77,3 City of Almaty 369 256 83,8 * Average rate of exchange (Central bank of Russian Federation) in 2022 was 100 KZT for 14.86 RUB. Table 5 The area of residential housing commissioned Area thou. m2 as percentage to 2021 level Republic of Kazakhstan 15 422,1 91,2 Akmola oblast 631,2 105,8 Aktobe oblast 1 252,3 106,0 Atyrau oblast 830,8 92,2 Kyzylorda oblast 683,2 103,3 Mangistau oblast 1 046,9 84,6 City of Astana 2 369,3 75,3 City of Almaty 1 720,5 65,4

135 JANUARY—FEBRUARY 2023 According to AO Eurasian Trading System Commodity Exchange, in 2022 207 contracts for the sale of cement were concluded for a total amount of 6,333.5 million tenge or US$ 13.7 million. The average purchase prices of PC 400‑D20 cement in 2022 was 28,052 tenge. According to Statistics Committee of the Republic of Kazakhstan data, in 2022 residential housing construction attracted investment of KZT 2,296.3 billion, 1.2 % more than in 2021. The average actual cost of construction of 1 m2 of gross floor area amounted to KZT 176.7 thou (13.3% more than in 2021). In 2022 42.1 thou. of residential and nonresidential buildings were commissioned, including 37,7 thou. of residential buildings. Their gross floor area and total structural volume were 15.4 million m2 and 51.9 million m3, respectively. The cost of construction in the republic and some of its areas and the amount of residential housing commissioned are shown in tables 4 and 5, respectively. International Cement Group International Cement Group Ltd (ICG) is a cement producer in the Central Asian region. ICG's facilities are located in Kazakhstan and Tajikistan. In Kazakhstan, the company owns full cycle plants TOO Alacem and TOO Sharcem with a total annual cement production capacity of 2.4 Mt. In addition, in September 2021, International Cement Korday Pte. Ltd., a subsidiary of ICG, established a joint venture to build a cement plant in Korday district of Zhambyl region for TOO Korcem with a production capacity of 1.5 Mt per year. TOO Alacem TOO Alacem, a joint Kazakh-Singaporean enterprise, built a dry process plant with a capacity of 1.2 Mt of cement per year in the village of Saryozek, Kerbulak district, Almaty region. The plant with clinker capacity of 3,200 t/day, equipped with modern equipment, started commercial production of cement in 2020. The Distributed Control System (DCS) en‑ sures that the required process parameters are maintained automatically. Effective dust-collecting devices, as well as dust and gas analyzers are installed at the enterprise; the data from them are transmitted online to the Monitoring Center of the Department of Ecology of the Almaty Region. Water reuse after treatment makes it possible to use it in the technological process and thus there is no wastewater. The main product of the plant is cement made in accordance with GOST 31108–2016 and GOST 10178–85 (M400, M450, M500). Main sales markets are the Almaty region and the city of Almaty. TOO Sharcem In 2021, TOO Sharcem, part of ICG, acquired a dry process cement plant in the town of Shar in Zharma district of East Kazakhstan region, which was previously owned by TOO Kazakh-Cement. The plant's clinker capacity is 2,500 tpd, cement capacity is 1.2 Mt per year. Limestone, clay and sandstone are used as raw materials. Coal is the process fuel. Basically the plant produces Portland cement of grades 400 and 500. The products are used in the construction of facilities in Kazakhstan and are also exported to Russia, Tajikistan, Uzbekistan and other countries. In 2022, the cement packaging equipment and a number of electric motors were replaced at the plant, and cement trucks were purchased. The replacement of the roller press and separator is planned for 2023. The source of investment is ICG's funds. The plan for 2023 is to reach an annual production capacity of 1 Mt. Korcem In 2022 the construction work on the project for construction of a modern dry method cement plant with annual capacity of 1.5 Mt was started in Korday township (Korday district of Zhambyl region). The license for the development of the quarry and mining of limestone has been obtained. It is planned to complete installation of 70% of the plant's equipment by the end of 2023. PR Department International Cement Group KAZAKHSTAN TOO Alacem. Plant view TOO Gezhuba Shieli Cement Company The cement plant of TOO Gezhuba Shieli Cement Company in the Kyzylorda region was built by the Chinese holding company Energy China as part of an investment project. The manufacturer of equipment for the facility is a subsidiary company of the group. The plant has a production capacity of 1 Mt of cement per year and produces it by the dry method. The main source of raw materials is limestone, which is mined in the company's own field 40 km from the plant. The company produces the following types of cements: • oilwell cement PCT I GG-CC 1; • standard cements: — CEM I 42,5N SR; — CEM I 52,5N; KAZAKHSTAN Plant view

136 JANUARY—FEBRUARY 2023 — CEM I 42,5N; — CEM II/A K 42,5N; — CEM II/A K 32,5N; — CEM II/A K 42,5R; — CEM II/A Sh 32,5N; — CEM II/A Sh 42,5N. TOO Gezhuba Shieli Cement Company is one of the few companies in the Republic of Kazakhstan producing oilwell cement. The plant uses a two-stage cement grinding system, including a two-roll roller press and a vertical three-roll mill, which makes it possible to obtain high quality products. Two 10-kt silos and a 40-kt silo are used to store clinker and finished products. Cement is shipped in bulk, in big bags and 50 kg bags. Products are delivered to consumers by rail and road. Production control is carried out with online analyzers. A.K. Tsagolov, head of department of sales, international trade TOO PO Kokshe-Cement TOO PO Kokshe-Cement is a cement plant with a production capacity of 2.0 Mt of clinker per year, located in the village of Zaozerny near Kokshetau. The construction project of the facility was accomplished by a company fully belonging to the Kazakhstani owners. Limestone and claystone from the Koksor deposit and quartz sand from the Belagash deposit are used as the main raw materials. The quarries are owned by the company. The company has its own certified laboratory, equipped with modern equipment, which allows to control the quality of raw materials and products at all stages of production. The plant has its own railway station, rail car fleet and railway spur tracks. The product range of the plant includes cements: • CEM I 32,5; • CEM I 42,5. For 2021–2023 it has been planned to take measures for modernization of dedusting devices and reduction of CO2 and pollutant emissions into the air. V.A. Novikov, Chief process engineer of TOO PO Kokshe-Cement KAZAKHSTAN Plant view TOO SAS-Tobe Technologies The company is located in Sastobe village of the Tulkubas district, Turkestan region. The Sastobe cement plant, commissioned in 1952, initially produced gray Portland cement. In 1967 the construction lime shop, consisting of two shaft kilns, with a capacity of 130 kt per year was put into operation. In 1969 the factory was halted for reconstruction with conversion to production of white and colored cements. The capacity of the plant was 388 kt per year. In 1983 the 3rd shaft lime kiln with productivity of 65 kt per year was put in operation. As later on the demand for white and colored cements decreased sharply while the demand for gray cement for housing construction grew, since the middle of 2006 the Sastobe cement plant switched to the production of gray cement. After the collapse of the USSR the plant went through difficult times. The hardest year was 2020. At the beginning of 2021 young enterprising businessmen came to the plant, and thanks to them the 3rd cement production line was started up in the shortest possible time. In 2022 the 2nd gray cement production line was renovated and put into operation. In 2023–2024 it is planned to reconstruct and commission the 1st line for the production of white and colored cement with a further increase in their output. Cement is produced by the wet method using limestone and loess loam. Two mills with the size of ∅ 2.6 × 13.0 m and one of ∅ 3.2 × 15.0 m are installed for grinding the raw material mix. Clinker is burnt in two rotary kilns of the following sizes: kiln № 2 — ∅ 3.6 × 150 m, kiln № 3 — ∅ 4 × 150 m. Hard coal is used as process fuel, natural gas is used for firing the kiln. The kilns are equipped with transom coolers. The plant has three cement mills with dimensions ∅ 2.6 × 13 m. The company manufactures the following products: • cements according to GOSTs 31108–2016 and 10178–85: — CEM II/A-Sh 32,5N (PC 400-D20); — PC CEM I 32,5 N (PC 400-D0); — CEM II/V-Sh 32,5N (ShPC 400-D20–80); — CEM III/A 22,5N (ShPC 300-D20–80); • lime of the 2nd and 3rd grades. PR Department TOO SAS-Tobe Technologies KAZAKHSTAN Plant view

137 JANUARY—FEBRUARY 2023 TOO Semey Cement Plant Industrial Company The cement plant in Semey has been in operation since 1958. The design capacity of the facility is 1.15 Mt of cement per year. Nowadays its production capacity is 1,05 Mt. The plant has four wet method clinker production lines. The raw material used is limestone from Novo-Taubinsk deposit in East Kazakhstan region, the clayey component is clay loams from Zhana-Semey deposit, coal from Kara-Zhyrinsk deposit is used as process fuel for clinker production. The Irtysh river is the source of the plant's water supply. The plant employs 1272 people. The plant produces the following cements: • according to GOST 31108–2020: — CEM I 32,5N; — CEM I 42,5N; — CEM I 42,5R; — CEM II/A P 32,5N; — CEM II/A Sh 32,5N; • according to GOST 22266–2013: — CEM I 32,5N SR; — CEM I 42,5N SR; • according to ТR ТS 014/2011 and GOST 33174–2014: — CEM I 32,5N DP; — CEM I 42,5N DP. Portland cement clinker is produced according to ST RK 3184–2018. The geography of product deliveries covers Kazakhstan, Russia and Uzbekistan. In 2022 the following was accomplished at TOO Semey Cement Plant Industrial Company: • the equipment of a new process grinding line with a vertical roller mill was 90% assembled, its commissioning is planned for II–III quarters of 2023; • the equipment for the 3rd line of cement filling into 50 kg polyethylene bags was purchased, its construction and commissioning are scheduled for 2023; • the construction of the 3rd line of cement filling into big-bags was completed; • the construction of the 2nd (last) section of the electrostatic precipitator of rotary kiln № 4 was completed; • a concrete-mixing unit with the capacity of 120 m3/h was commissioned, which made it possible to produce ready-mix concrete of different grades; • the shop for production of polystyrene concrete wall panels was put into operation, a new line for production of polystyrene concrete brick blocks was purchased. Wall panels for civil construction are produced in the same shop and a house-building factory is under construction. For 2023 it is planned, in addition to the above: • to develop the project of capital repair and purchase the equipment of the electrostatic precipitator for rotary kiln No. 3; • to develop a project and perform the installation of an automated system for monitoring the exhaust gases of rotary kiln No. 4. V.M. Ivanov, Engineering Director TOO Semey Cement Plant Industrial Company KAZAKHSTAN Cement silos United Cement Group United Cement Group is the largest cement holding company of Central Asia operating in Uzbekistan, Kyrgyzstan and Kazakhstan for more than 15 years. In Kyrgyzstan the Group includes the plants OAO Kant cement plant and OOO Tekhnolin both located in the town of Kant (Ysyk-Ata district, Chui region). United Cement Group takes an active part in the development of the region — the products of the Group's companies are widely used in the construction of the most significant infrastructure projects in Uzbekistan and Kyrgyzstan. The Group is constantly modernizing its production facilities and launches new lines to increase productivity, reduce harmful emissions and improve the quality of the products. The total production capacity of the companies of the Group in Kyrgyzstan and Uzbekistan by the end of 2022 was more than 10 Mt of cement per year. The product range is represented by: • standard cements: In Kyrgyzstan the full cycle cement plants comprise OAO Kant Cement Plant, OOO Southern Construction Materials Plant, ZAO Southern Kyrgyz Cement and two more companies. According to the National Statistical Committee of the Kyrgyz Republic, in 2022 the production of cement increased by 7.1% (to 2,666.6 kt), readymixed concrete output — by 14.0% (to 934.4 kt). Precast constructions output decreased by 6.4% (down to 132.0 kt). 118.5 kt of cement were imported for the sum about US$ 5.4 million. 587.8 kt of cement were exported for the sum about US$ 24.7 million. The average purchase price in 2022 for 50-kg bag of cement amounted to nearly 354.1 KGS, the average producers' price was 5,780.2 KGS per 1 tonne. In 20221,119.1 thou. m2 of housing were commissioned in the country (14.8% less than in 2021). Construction contract costs were 49.6 billion soms (7.6% more than in 2021). The average exchange rate of Bank of Russia in 2022 was nearly 100 KGS per 81.0 RUB. KYRGYZSTAN KYRGYZSTAN

138 JANUARY—FEBRUARY 2023 — CEM 052,5N; — CEM 032,5N; — CEM I 42,5N; — CEM I 32,5N; — CEM II/A‑I 42,5N; — CEM II/A‑I 32,5N; — CEM II/V‑K 32,5N; — CEM II/A‑K (P‑I) 32,5N; — CEM IV/A (P) 32,5N; • special cements: — CEM I 32,5N SR; — CEM II/A‑P 32,5N SR; — CEMENT I 42,5N SR; — PCKh; — PCT. ОАО Kant Cement Plant The company is the major manufacturer of cement products and the flagship of the construction industry of Kyrgyzstan. In 2021 a new compressor unit was installed at the plant, the aspiration system of cement silos was up‑ graded and an overhaul of bag filters was carried out. In 2021–2022 the cement mill No.8 was re‑ vamped and converted to closed circuit grinding. PR Department United Cement Group Kant Cement Plant OOO South Construction Materials Combined Works 914.0 kt of clinker and 789.3 kt of M400‑D20 Portland cement were produced. 789.0 kt of cement were shipped to the cus‑ tomers by road, of this amount 150.5 in bulk and 518.1 kt in 50 kg bags, including 120.4 kt that were exported to Uzbekistan. According to OOO South Construction Materials Combined Works KYRGYZSTAN ZAO Rybnitsky Cement Combined Works In 2022 430 kt of clinker and 540 kt of cement were produced. 170 kt of cement were bagged. According to ZAO Rybnitsky Ce‑ ment Combined Works MOLDOVA According to the National Bureau of Statistics of the Republic of Moldova, in 2022 the volume MOLDOVA of construction works in the country decreased compared to the same period of 2021 by 6,6 %. The indicators have been calculated in com‑ parable prices. TAJIKISTAN The number of integrated cement plants in Tajikistan includes 2 plants of the International Ce‑ ment Group holding, OOO Huaxin Gayur (Sugd) Cement, OOO Huaxin Gayur Cement, OOO Ganch, OAO Sementi Tojik and 10 more plants. According to Statistical Agency under President of the Republic of Tajikistan, in 2022 the volume of production was 4,352.6 kt of cement (1.7% more than in 2021), and 431.6 thou. m3 of ready-mixed concrete, which is 8.2% decrease comparing to 2021. The averege price of cement producers for 2022 was TJS 570.9 per 1 t, the purchase price of cement for 2022 was TJS 802.4 per 1 t. Bank of Russian's average exchange rate in 2022 was 1 TJS or 6.23 RUB. In 20221,701.5 thou. m2 of housing were com‑ missioned in the country (19.0% more than in 2021), 334.1 thou. m2 were commissioned in the Khatlon region (0.1% more than in 2021), 547.5 thou. m2 in Sogdian region (21.6% more than in 2021). International Cement Group In Tajikistan, the International Cement Group holding owns an integrated plant OOO MPO Zhongtsai Mohir Cement and a grinding plant OOO Mohir Cement. In 2022, these enterprises produced 1.92 Mt of cement. PR Department International Cement Group TAJIKISTAN

139 JANUARY—FEBRUARY 2023 According to the Uzpromstroymaterialy Association, in 2022 the production of clinker and cement in Uzbekistan grew by 2.0 % (to 12,372 kt) and 2.9 % (to 14,607 kt) in comparison with 2021, respectively. Domestic cement consumption totalled 16,509.9 kt; 411.1 kt was exported; non-centralized imports totalled 2,250.2 kt (including 14.5 kt of white cement imported from Iran). 6,261.1 kt of cement was sold through commodity exchange trading. According to the National Statistics Committee of Uzbekistan, in 2022 the volume of construction in the country grew by 6.3 % to UZS 130,767 billion. The average exchange rate of Central Bank of Uzbekistan was equal to 1,000 soums per 6.2 rubles. UZBEKISTAN UZBEKISTAN AO Bekabadcement. Plant view AO Quvasoysement. Plant view United Cement Group The United Cement Group owns full-cycle cement plants in Uzbekistan: Bekabadcement (Bekabad, Tashkent region). Yangiyul grinding station (Yangiyul, Tashkent region), Qizilqumsement (Navoi Region, Navoi-3), and Quvasoysement (Fergana Region, Kuvasai), as well as AO Quartz — the largest glassware manufacturer in Uzbekistan. AO Bekabadcement The plant produces cement of high quality. The main part of cement is produced by the dry method. In the course of modernization of production the kiln and decarbonizer burners, a 4th generation cooler were installed and the equipment of all preheaters was replaced. At the end of 2022 the reconstruction of the dry production process line began, which will allow the plant to increase production capacity from 2,500 to 3,000 tons of clinker per day and improve its product quality indicators. AO Qizilqumsement One of the largest cement plants in Uzbekistan producing products by the dry method was put into operation in 1977. In 2022 a new production line was commissioned which increased the total annual production capacity of the plant by 1.8 Mt of cement (up to 5.4 Mt). The plant produces sulfate-resistant, oilwell cement, additive-free cement and also manufactures and exports first-class lime, reinforced concrete products, ready-mix concrete, refractory bricks, slate and aggregates. AO Quvasoysement is one of the biggest and most up-todate factories producing cement and building materials in Uzbekistan and Central Asia countries. The United Cement Group is modernizing the plant and constructing a new grinding station with the capacity of 100 t/h (750 kt a year), a tube mill and a roller press. PR Department United Cement Group subscription 2023 tel. +7 812 242 1124 [email protected] AO Qizilqumsement. Plant view

140 ÌÀÐÒ—ÀÏÐÅËÜ 2015 140 English pages JANUARY—FEBRUARY 2023 derground. The higher cost of this method including storage infrastructure the cost of capture is going down as technology is used more affordably at smaller scales. The challenge is how to make these technologies affordable in commercia scale. Additionally, new calciner configurations can enable electrification or the use of alternative fuels while maintaining the separation of process and fuel emissions. Leilac is currently using technology to capture about 100,000 TPA of CO2 in Hanover, Germany, and construction will start in 2023. Some of the difficulties associated with capture and storage can be solved by using carbon in fuels, chemicals, building materials, and other products. Concrete is cured using CO2 in CarbonCure and Carbicrete, for instance. The concrete mix and the injected CO2 react, forming calcium carbonate that increases the concrete’s compressive strength and enhances its durability. Clinker substitution and additional cementitious materials. Clinker substitution entails replacing clinker with increasing volumes of SCM. Depending on the rate of substitution, these cements, which are now produced on a large scale by many cement companies, can dramatically reduce emissions. The method may be restricted by prescriptive standards (which call for minimum clinker ratios) and may be restricted by the availability of additional cementitious materials in the future (common SCMs include fly ash from the coal-fired plants or blast furnace slag from the steel industry). Fund raising efforts by innovators to scale the use of substitute supplementary cementitious materials are increasing. To speed up the commercialization of Terra’s OPUS cementitious materials derived from a variety of regional feedstocks and waste products, Terra CO2 raised $46M in June 2022. When post-consumer coloured glass fines are activated using Carbon Upcycling’s carbon utilisation technique, CO2 emissions are sucked up and high-performance SCMs are created. This technology is now in pilot testing. Fund raising efforts by innovators to scale the use of substitute supplementary cementitious materials are increasing. To speed up the commercialization of Terra’s OPUS cementitious materials derived from a variety of regional feedstocks and waste products, Terra CO2 raised $46M in June 2022. When post-consumer coloured glass fines are activated using Carbon Upcycling’s carbon utilisation technique, CO2 emissions are sucked up and high-performance SCMs are created. This technology is now in pilot testing. Alternate raw materials, integrated processes, and alternative cements. Using alternate raw materials or techniques that do not require calcining limestone for clinker manufacture can significantly reduce emissions. The materials used as SCM are frequently also employed as binding materials (when activated). The use of «bio-cement,» which is made when organisms break down limestone and then reconstitute it to create an end product like bio-concrete, can also result in significant reductions. Across the value chain innovation. The cement industry’s emissions can be greatly reduced through innovation, but it will need finance to scale and lower costs. An emphasis on performancebased standards can also assist alternative cements get access to the market. Additional innovation across the value chain is also to be anticipated: large amounts of CO2 can be sequestered by the mineralization of aggregates, production facilities can benefit from software that optimises production processes and blends, and concrete 3D printing can help with installation optimization. One of the businesses seeking to exploit carbon dioxide emissions to produce fuels or chemicals is Synhelion. The startup creates syngas from CO2 and water using focused sun radiation. In December 2022, the company raised $24 million from CEMEX and other sources, and is presently building an industrial facility to make sustainable fuels with solar heat (and captured carbon). In order to create solar clinker, the startup additionally connected its solar receiver to a CEMEX clinker production process one of the holding’s enterprises in order to exclude the use of natural fuels in this process (without use of fossil fuels). 1. Introduction 0.7 gm of CO2 will be released during the production of 1 kilogramme of OPC. Most of the emissions are caused by the production of clinker. Between 50 and 60 percent of these emissions are caused by the calcination of the limestone, and the majority of the rest are caused by burning fossil fuels to reach the necessary kiln temperatures. The production of cement is responsible for about 7—8 % of all carbon dioxide emissions in the world. By 2050, the demand for cement will increase in tandem with population growth. It will be crucial to reduce these emissions if the world is to meet its climate goals. 2. Innovation is being used to address the abatement challenges in the cement industry The cement industry faces especially difficult challenges when it comes to reducing emissions. Because manufacturers’ profit margins are too narrow to cover them, new industrial processes that produce less pollution typically have higher production costs. Industry is also resistant to change because it has heavily invested in the current system of doing things. Clinker substitution and carbon capture, to a lesser extent, are established mitigation techniques. Both must overcome specific obstacles. Alternative fuels, such as used tyres and household waste, plastics etc. are frequently used. The process releases carbon from these wastes while displacing the use of fossil fuels. Process innovation, carbon capture, and use. Carbon capture entails separating CO2 from other gases in exhaust in order to store CO2 unCement industry striving for carbon neutrality UDC 666.94:504.7 Dr. S.B. Hegde, Professor, Jain University, India, and Visiting Professor, Pennsylvania State University, USA ABSTRACT. The means of reducing greenhouse gas emissions in cement industry include the replacement of part of the clinker in cement with mineral additives, the use of alternative raw materials and fuels, the recarbonization of materials, the development of innovative technologies, etc. The article provides information about a number of projects aimed at reducing CO2 emissions during the life cycle of cement, and about the costs associated with reducing its carbon footprint. Keywords: CO2 emissions; supplementary cementitious materials; alternative raw materials and fuels; carbon capture, utilization and storage.

141 ÌÀÐÒ—ÀÏÐÅËÜ 2015 141 JANUARY—FEBRUARY 2023 3. Despite the Genuine Effort made, much remains to be done The major players have vowed to achieve carbon neutrality by 2050 through the Global Cement and Concrete Association (see the figure 1). By 2050, cement manufacturers would actually need to reduce emissions from one tonne to 375 kilos of CO2 per tonne of cement produced. If this goal is to have any chance of success, it will be costly and ambitious. Around 80 % of the emissions are produced during the cement-making process, specifically during the chemical transformation of clinker, the product of firing clay and limestone rocks at a temperature of about 1450 °C. Clinker makes up 95 % of Portland cement, a conventional and extremely unfriendly cement. With the use of greener substitutes like waste products, cement companies are concentrating on lowering the percentage of clinker in the composition of cement (e.g., Fly ash). Additionally, recycling materials strengthens circular economy initiatives and generates significant cost savings. The effectiveness of manufacturing procedures must be increased by cement manufacturers. This can be accomplished by making investments in new locations and switching to cleaner kiln fuels. A specific illustration of this is the use of biomass waste in place of the fossil fuels previously used to power kilns. Industry leaders like Holcim have been able to reduce their emissions by 30 % since the 1990s and are aiming for an additional 20 % reduction between now and 2030 as a result of these measures. The carbon intensity directly associated with cement production, however, increased by 1.5 % annually between 2015 and 2021, despite the fact that the IEA estimates a 3 % annual reduction is required until 2030 in order to achieve a «net zero emissions» scenario for 2050. With 6 % of all man-made emissions, cement is the second largest industry emitting after steel. Societal needs and urbanization are expected to increase cement demand by 45 % by 2050. As part of the Net-Zero by 2050 pathway proposed by the IEA, however, the increase should be limited to today’s levels. The cement industry can already reduce emissions today without introducing disruptive technologies by leveraging efficiency and circularity levers like lowering the clinker-to-cement ratio and utilising waste from other industries as alternative fuels. The only known method for bringing sectoral emissions close to zero is by using CCUS technology. Its use today could result in a 50—85 % rise in production costs. By 2030, the technology is anticipated to be at the commercial level (?). In addition to investments in carbon capture on industrial assets, at least $ 185 billion is required to create the infrastructure for low-emission power and hydrogen production, as well as the transport and storage of 1,370 MTPA of CO2 (the second-largest need in the IEA Net Zero by 2050 Scenario). Low-carbon cement is anticipated to enter the market with a green premium above 50 % due to 1 Getting to net zero. URL: https://gccassociation.org/ concretefuture/getting-to-net-zero/ (accessed on 15.01.2023). the high cost of carbon capture, which would result in a 1—3 % rise in housing costs. The cement consumers’ demand signals for low-emission cement are essential for motivating investments. To do this, cement buyers’ confidence in their capacity to transfer the premium on to final consumers must be strengthened. For first movers in the low-emission cement sector, greater international collaboration and stronger regulatory measures, such as carbon pricing, carbon border adjustment mechanisms, circularity, or product specification standards, can help develop a competitive and financially sustainable market. By 2050, the sector will need to invest $500 billion in carbon capture technologies, or $16 billion annually on top of current investments. A sufficient taxonomy and substantial governmental finance assistance will make it easier to get green bonds, which will help the business case. 4. Avenues for Net Zero Potential: We reiterate the following actions on immediate basis: • Introduce efficiency measures to promote recycling of concrete and maximise emission reduction in current operations. • Increase the number of carbon capture initiatives to quicken the technology’s learning curve, lower costs, and advance commercial readiness. • Create the infrastructure needed for CO2 transit and storage to enable the production of low-emission cement. • Increase the number of low-emission cement demand signals to encourage investors and manufacturers to invest money in low-emission assets. • Create policies to support the aforementioned four targets and bolster the commercial viability of producing low-carbon cement. • Electrification with storage. Renewable energy has helped dramatically reduce the carbon intensity of electricity across the globe. • Green gas and biomass, hybrid heating, Hydrogen and CCUS. 5. Conclusions There is a lot of work that needs to be done. International standards must be used to define «low-emission» industries. Technologies for carbon-free manufacturing must demonstrate their viability on a large scale. Consumer acceptance and awareness must increase in order to generate demand for low emission products. Building infrastructure is necessary to develop and integrate low-carbon processes. Markets with low carbon emissions need to become profitable. It is necessary to «de-risk» investments to speed up capital inflows. Change can be encouraged and facilitated with a solid policy foundation. Governments and businesses should step up their efforts to quicken the decarbonization process, increase energy efficiency, and lessen reliance on fossil fuels. These and other objectives cannot be achieved without a paradigm shift in multistakeholder collaboration across vast industrial ecosystems. If equity and justice are not prioritized during industry transitions, neither of them can be achieved. It is necessary for people’s opportunities and means of subsistence. Industrial decarbonization might be one of the most challenging energy transition challenges to overcome. The industry has well-established paths to net-zero, and transparency is rising. We might look back on this decade as one of the major turning points for net-zero sectors if the global aspiration and spirit of cooperation inspire effective action. Getting to Net Zero — GCCA Roadmap ÑÎ2 emissions, Gt Societies need for concrete (in the absence of any action) is forecast to result in 3.8 Gt ÑÎ2 in 2050. Contributions to achieve net zero Efficiency in design & construction Efficiency in concrete production Savings in cement & binders Savings in clinker production Carbon capture and utilization/storage De-carbonization of electricity ÑÎ2 sink: recarbonization Total reduction % Contribution to net zero 4,0 3,5 3,0 2,5 2,0 1,5 1,0 2020 2030 2050 22 11 9 11 36 5 6 100 0 0,5

142 ÌÀÐÒ—ÀÏÐÅËÜ 2015 142 English pages JANUARY—FEBRUARY 2023 trusion. In this context, 3D printable concrete is a “tailor-made” material which can be delivered by the pumping system and extruded through the nozzle of a 3D printer. Then, after its deposition, it maintains its shape stable under the gravitational load of subsequent printed concrete layers without the requirement of formwork. Compared to conventional concrete, 3D printable mix, is a novel, automatic, digital technology which brings numerous benefits to construction, like highly flexible architectural design, formwork-free fabrication, faster construction, material savings, etc. [5—6]. Contour crafting method is globally used in 3D printing as it is uses systematic deposition of material as directed by 3D model from printer. Any complex shape can be made by 3D printing, if control can be made on the behaviour of printed material. The rheological properties of printed concrete are most critical in 3D printing of any object. Similarly, the mix design and its compatibility with printing parameter are equally important. The 3D printable mix requires a flowable consistency until it remains in printing nozzle while its requirement gets changed from a flowable mix to plastic mix which remain plastic until next layer get print and after that it must gain sufficient yield stress that can bear the weight of successive printed layers [5—6]. The mix design and its optimisation plays an imported role in successful printing of 3D printable objects. The optimum water content and dose of chemical admixture maintain the flow in the mix while the optimum ratio of cementitious materials and fine aggregate content gives an optimum density which gets pumped through pipe and nozzle and gives a printable mix without compaction for a layer by layer print. Jun Ho Jo et.al [7] developed a 3D printer for concrete structures for testing of cementitious materials for laboratory testing purpose. They developed a concrete 3D printer 1m × 1m × 1m for different design mixes to find their suitability and efficacy for the developed of 3D printable mortar. Jia Chao Lin et.al. [8] studied the effect of Processing Parameters on 3D Printing of Cement — based Materials and concluded that in 3D printing with cement-based materials, the material properties and process parameters have a great impact on the printing process. They showed that the best single-layer height and nozzle diameter ratio are between 0.4—0.6. The best parameters for the equipment are (a) output displacement is 9 · 10–2 m3/h, (b) printing speed 1. Introduction Concrete is generally placed into formwork and then vibrated to fabricate structural components. Two alternative construction strategies namely self-compacting and sprayed concretes have been developed to eliminate the compaction process. 3D concrete printing is a latest technology that shows great potential with respect to the increase of productivity and safety in construction [1—4]. Based on past research, it is seen that economically feasible concrete printing approaches are based on layered exRole of material selection in mix optimization of 3D printable concrete UDC 691 A. Trivedi, M. Tech, Joint Director; M.K. Mandre, M. Tech, Group Manager; B. Singh, M. Tech, Group Manager; P.N. Ojha, M. Tech. Joint Director & Head, National Council for Cement and Building Materials, India ABSTRACT. The printing process is a novel digitally-controlled additive manufacturing method which can build architectural and structural components without formwork, unlike conventional concrete construction methods. The most important fresh properties are extrudability and buildability, which have mutual relationships with workability and open time. These properties are greatly influenced by the mix proportions and the presence of superplasticiser, retarder, accelerator and polypropylene fibres. The present study is about optimisation of material quantity to obtain a 3D printable mix with 3D printer. Cement, fly ash, silica fume, fine aggregate, water and chemical admixture are used for developing a 3D printable mix and optimum dose of chemical admixture such as PC base chemical admixture and Viscosity Modifying Admixture (VMA) is used to optimise the 3D printable mix. The study indicated that the dosage of superplasticizer needed to achieve the similar flow value increases as a/b increases. The plastic viscosity increased by about 35 % when a/b increased from 0.75 to 0.9. The flow was ranging from 160 to 225 mm which indicates dependency on the material type and packing density. Study also highlighted that yield stress of mix is important to achieve buildability and low yield stress value can lead to collapse of layers and will also prevent layer wise buildability. The optimum dose of polypropylene fibre was found to be 0.1 % to achieve 3D printable mix without clogging or shrinkage crack. The open time is found to be about 12—15 minutes for the materials. Studies reported in this paper highlights that both mix optimisation with different combination of cementitious binders and selection of optimum dosage of superplasticizer and VMA are very critical in achieving a 3D printable concrete. Keywords: 3D printing, concrete mix, flow, buildability, yield stress, open time. Fig. 1. Schematic diagram of Extrusion based printing [4] Extrusion nozzle Built part Build piston Build platform Z Y X Slurry

143 ÌÀÐÒ—ÀÏÐÅËÜ 2015 143 JANUARY—FEBRUARY 2023 should be controlled in 4—8 cm/s. At the same time, 3D printing should try to choose a shorter length of the pipeline, and ensure that the pipeline should be straight to avoid the pipe bending and suspension. The prevalent processes of 3D printing are Extrusion-based printing, Binder jetting, Mesh mould approach (cutting and welding) etc. The additive process in construction with automation is further developed by Khoshnevis [4]. Among all the processes, the most widely used method is the Extrusion-based printing. A critical issue in 3D printable mix is the selection of raw materials and the mix design so as to meet the pumpability, extrudability and buildability which are key process-related material characteristics required for a successful 3D concrete printing. These characteristics are beyond the general requirements to concrete as described in codes and guidelines by consistency classes and corresponding workability testing. There are some empirical mix design methods for 3D printable mix which have been suggested by past researchers [9] but there are still no commonly accepted mix design methods. Set of trial experiments done in past has indicated a flow value of 50—60 % suitable for designing the printable mixtures. Similar flow values are reported in the literature for printable concrete [10—15]. The rheological measurements with granular suspensions like cementitious mixtures are prone to effects like particle migrations and solvent drying. These factors may have an influence on the results and are some of the limitations on performing rheological measurements with cement-based materials [14—15]. While a highly workable material is needed for 3D concrete printing to ensure easy transportability (usually by pumping) to the printing head, the extruded material is required to be relatively stiff to ensure that the deposited filaments retain their shape [16]. Nozzles of various orifice shapes such as rectangular, square, circular and elliptical are in use. The nozzle orifice shape may be chosen as per the intended use. Circular nozzles offer ease of printing at corners or changes in angle of the structure to be printed. But the lesser contact area between extruded beads may affect the stability of layers [17]. In 3D printing, buildability is a challenging material issue and to overcome it, the freshly extruded material should regain its initial viscosity and yield stress prior to the deposition of the next layer over it Layer deformations may cause instability [18—20]. There are numerous factors which affect the printability of concrete simultaneously, it still can be briefly inferred that increasing the volume fraction of solid phase (including aggregate and fiber) and reducing the paste volume are beneficial for the buildability but may compromise the pumpability and extrudability of 3D printable mix. The influences of paste volume in concrete system could be inversely applied for volume of aggregates. Increasing aggregate volume fraction enhances the required pumping pressures [21—22], due to the increase in viscosity. Usage of coarse aggregates significantly influences the pumpability and extrudability of the 3D printable mix. If a particular maximum aggregate size is critical or not is dependent on the pump and print head setup, especially the nozzle diameter. Pozzolanic cementitious materials with combination of fly ash and silica fume, can mitigate cold joints and the variation of overall strength to a great extent in 3D printable mix, which can be attributed to less pore and the formation of denser microstructure at the layer-interface. However, this effect also depends on the moisture in the concrete system for the further pozzolanic reaction of these materials [23—27]. It should be understood that 3D printing technology will have a limitation to the selection of some parameters in mix design, such as the size of aggregate and the type of fiber, which will further impact the mechanical, time dependent and durability property of concrete mix. In principle, materials (thixotropic) with high (static) yield stress and low viscosity, are suitable for concrete printing application. The studies have indicated that the paste to aggregate ratio has a great impact on the printability of 3D concrete. However, defects and weak interlayer surfaces can be seen in the printed specimen, resulting in a significant reduction in the mechanical performance of the printed specimen when compared with the cast concrete depending upon aggregate content [23—29]. Different from the densely packed structure of conventional cast concrete, 3D printed concrete needs more paste to coat and cover the aggregates so that the aggregates can be suspended in the paste to ensure the extrudability requirement. However, too much paste other way creates a decrease in buildability [24—30]. The aim of this study is to present the mix design concepts of 3D printable concrete mix. The present study is about optimisation of material quantity to obtain a 3D printable mix with 3D printer. Cement, fly ash, silica fume, fine aggregate, water and chemical admixture are used for develop a 3D printable mix and optimum dose of chemical admixture is used to optimise the 3D printable mix. 2. Materials Commercially available Ordinary Portland Cement (OPC) of 43 grade conforming to the physical and chemical requirements of IS 269 has been used as the main binder in all the concrete mixes. Mineral admixtures such as Fly Ash (FA) conforming to requirements of IS 3812 (Part 1) and Silica Fume (SF) confirming to IS 15388 [33] have been incorporated in different combinations and proportions to make various binary and ternary concrete mixes. The physical properties and chemical composition of these materials are given in Table 1 & Table 2. Fine aggregates (crushed fine aggregates of zone III as per IS 383) conforming to requirements of IS 383 were used as fine aggregates. Polycarboxylate ether (PCE) based super-plasticizer conforming to IS 9103 and Viscosity Modifying Admixture (VMA) was used. 3. Experimental plan Based on the past studies, an experiment plan is prepared for studying fresh properties of 3D printable concrete. OPC 43 grade Cement, fly ash, silica fume, fine aggregate (<2.36 mm), water, PC base chemical admixture and Viscosity Modifying Admixture (VMA) were used to develop a 3D printable concrete mortar. Due to different principles and printing process, 3D printing equipment cannot be universal in different areas, but the equipment operating principle is relatively consistent. The following parameter (Table 3) of customized 3D printer were fixed for development of 3D printable concrete. Provision of Two arrangement for liquid additive mixing nozzle shaft with injection control rate by software was kept. Based on literature review and customized 3D printer parameters, the following materials ranges (Table 4) were considered for development of 3D printable concrete. Table 1 Physical properties of OPC and mineral admixtures Properties Cement Fly Ash Silica Fume Fineness (m2/kg) 323 334 1670 Specific Gravity 3.15 2.19 2.28 Table 2 Chemical composition of OPC and mineral admixtures, % OPC 43 Fly Ash Silica Fume Loss of Ignition (LOI) 2.30 3.64 2.73 Silica (SiO2) 20.71 62.53 85.03 Aluminum oxide (Al2O3) 5.15 23.58 – Calcium oxide (CaO) 59.96 1.17 – Magnesium oxide (MgO) 4.57 0.50 – Alkalis Na2O 0.42 1.23 0.73 K2O 0.56 – 2.96 Chlorides 0.012 – – Insoluble Residue (IR) 1.25 91.92 – Table 3 Details of customized 3D printer S. No. Parameter Range 1 Print size 0.5—1.0 m 2 Nozzle moving speed 0.010—0.050 m/s 3 Discharge rate 0.050—0.100 M3/min. 4 Layer width 25 mm 5 Layer height 10—15 mm Table 4 Materials ranges considered for development of 3D printable mortar Sl. No. Material Range of use 1 MSA 2.36 mm 2 Total cementitious material 800—1100 Kg/m3 3 OPC 43 grade cement 300—600 Kg/m3 4 Flyash 300—500 Kg/m3 5 Silica fume 50—135 Kg/m3 6 Water 250—330 Kg/m3 7 Chemical Admixture PC base 0.1—0.5 (% by mass of total cementitious) 8 Viscosity Modifying Agent 0.05—0.20 (% by mass of total cementitious)

144 ÌÀÐÒ—ÀÏÐÅËÜ 2015 144 English pages JANUARY—FEBRUARY 2023 4. Mix design details In order to optimize the mix, more than 30 trials were done and six mixes with following proportions (Table 5) were prepared and flow, extrudability, printability and buildability were tested for all the mixes. Mixing was done in a pan type mixer attached to 3D printer setup. Initially dry mixing of fine aggregate and cementitious materials was done for two minutes. After that water was added with superplasticizer. The mixing was stopped after two minutes and further VMA was added and mixing was continued for two minutes. From a set of trial experiments, a print flow value of 70—80 % was found to be suitable for designing the printable mixtures. Similar flow values are reported in the literature [19—21] for printable concrete. The aggregate-to-binder ratio (a/b) was kept in range from 0.75 to 0.9 and the dosage of superplasticizer was adjusted to achieve a flow value in the range of 60—80 %. A nominal VMA dosage in range of 0.05 % to 0.1 % of the binder was used for all the mixtures. The dosage of superplasticizer needed to achieve the similar flow value increases as a/b increases. This is due to the reduced water content in the mixtures with higher a/b. The flow of mix was measured by flow table as procedure given in IS: 1727—1967. The range of flow in mm was 160 to 225 mm. The appropriate way to design compositions with high paste volume is to use additives as replacement of Portland cement. The plastic viscosity increases by 35 % when a/b increased from 0.75 to 0.9. This increasing trend in plastic viscosity can be explained by the Krieger-Dougherty model [21]. Few trials were also done with Polypropylene (PP) fibers. The length and thickness of the fibers were 12 mm and 40 µm respectively. The range of compressive strength for the mixes was between 45—55 MPa. If volume of paste is enhanced by increasing cement content or with another fast reacting binder, then buildability is expected to improve with paste volume. In contrast, if the paste volume is enhanced by adding inert or slow reacting additives, then buildability may remain the same or sometimes it decreases. As far as the parameters in the mix design of 3D printed concrete are to be taken care, it is to be noted that the choice of mix constituents and their proportions depends upon features of 3D printing technology applied, as indicated in Fig. 2. 3D printed concrete have high binder content in order to achieve the extrudability. The absence of coarse aggregate and excessively high binder content leads to higher plastic, autogenous and drying shrinkage, and as a subsequently lead to a higher probability to cracking. To mitigate the shrinkage induced cracking of 3D printed concrete, the addition of fiber has become a solution. 5. Results and discussion It was seen that extrudability and buildability depends on various factors but to reduce the complexity in mix design, the consistency / flow of trial mix was altered by adjusting the superplasticizer dosage. The concrete mix was found pumpable and continuously extrudable from 25 mm nozzle size. The printing was done with optimised concrete mix-4 for nine layers with 0.225 metre height. The circle printed with this concrete was found stable and retained its shape till final layer of printing. Printing speed of the nozzle of 3D printer was kept as 2 cm/sec. In few trials of 9 layers of 25 mm each, shrinkage cracks was noticed in the previously printed objects, further experiments were performed by adding Polypropylene fiber in concrete mix so that cracking can be avoided in 3D printed objects and stability gets improved. The Polypropylene fiber were added in varying amounts of 0.1 % and 0.25 % by volume of concrete (refer table-5). Although the mix designs achieved the optimum flow spread value for dispensing and layering of the materials, the screw inside of the nozzle compartment malfunctioned and got choked when the concrete contained more than 0.1 % of PVA fibers. The mix design with 0.1 % PVA fiber did not cause clogging in the nozzle compartment. Therefore, the optimum ratio is found to be 0.1 % of the fiber that print material without clogging or shrinkage crack. Past studies has indicated that higher printing speed will have an impact on single layer stack stability. Superplasticizer dosage in range of 0.10 % to 0.25 % gave continuous extrusion of material without blockages in this study. Past study by Rahul et.al. [10—11] also suggested that above 0.10 % superplasticizer dosage continuous extrusion of material was possible without blockages. The width and thickness of the extruded layer conformed with dimensions of nozzle leading to “passing” in extrudability test. There was no deformation of bottom layer when it is checked for more than eight layers (figure 3) for superplasticizer dosage of 0.10 %. However, on further increasing superplasticizer dosage to 0.15 %, there was a 5 mm compression of the bottom layer. With a lower superplasticizer dosage, the yield stress were increasing as VMA dose increases allowing extrudability, whereas flow was not giving definite trend & was ranging from 160 to 225 mm which indicates dependency on the material type and packing density. Static yield stress is defined as the maximum stress which is needed to make the material flow from its state of rest. Below the yield stress, the material exhibits elastic behavior and does not flow. The static yield stress of printable concrete is measured of above mixes with the help of Vane Shear apparatus. The initial obtained shear stress of printable mix is given in Table 6. The influence of superplasticizers on the viscosity has been Table 5 Mix details of 3D printable concrete Sl. No. Cement kg/m3 Fly Ash kg/m3 Silica Fume kg/m3 PC Admixture VMA Water kg/m3 Polypropylene fibers % by volume of concrete Fine Aggregate (<2.36) mm kg/m3 Percentage by weight of cementitious material Mix 1 300 600 100 0.25 0.10 320 — 900 Mix 2 300 600 100 0.17 0.05 280 — 832 Mix 3 225 540 135 0.15 0.07 290 — 750 Mix 4 300 600 75 0.14 0.06 295 — 730 Mix 5 400 500 100 0.20 0.10 295 0.10 % (1.00 kg) 825 Mix 6 400 500 100 0.22 0.08 295 0.25 % (2.5 kg) 825 Fig. 2. Limitation in parameters for mix design for 3D printing technology [31, 32, 33] 3D printing restricts Maximum diameter of aggregate High binder content Shrinkage issue Fiber reinforcement Fig. 3. Printed object using optimized concrete mix

145 ÌÀÐÒ—ÀÏÐÅËÜ 2015 145 JANUARY—FEBRUARY 2023 investigated before by past researchers [10—15], and there exists a general agreement on the fact that, although superplasticizers decrease the yield stress, it does not decrease the viscosity of the cementitious mixtures significantly. It was seen that the increase in yield stress with increase in a/b is not significant as compared to the increase observed for the plastic viscosity. High (more than 50 %) paste volume and low (less than 50 %) dosage of aggregates enables better pumpability and extrudability at a constant concrete consistency. Table 6 Flow measurements and yield stress of 3D printable mortar Sl. No. Mix Initial static yield stress (kPa) Open Time (minutes) 1 Mix 1 1.72 15 2 Mix 2 1.80 14 3 Mix 3 1.78 14 4 Mix 4 1.84 14 5 Mix 5 2.23 13 6 Mix 6 2.15 12 It was seen that the material was not extrudable after average 12—15 minutes when the material reached its open time limit. It was difficult to print the materials after this limit. However, the open time can be controlled by adding the dosage of superplasticizer suitably in the mix. For the specimen with average of 12—15 minutes of the time interval, the layers were well bonded together. However, only the surfaces exposed to the air are bonded while boundary lines of each layer is observed for the specimen with average 20 min of the time interval for the mix-1 to mix-6. The cross section for 40 minutes of the time interval showed each layer as a separate entity. It was observed that the boundary line became more noticeable as the time interval increased. Based on this, the maximum time gap required between printing layers was found to be average 12 minutes. The extruded layer should have a short time gap before the subsequent layer of concrete is deposited on top of previous layer. This is needed, so that the layers can maintain sufficient chemical activity and plasticity to adhere with the next layer. Otherwise, the finite ‘‘waiting time” between layers can lead to formation of cold joints. The yield stress of fresh concrete is the critical parameter which determines the shape stability. Yield stress increases over time in absence of agitation and shear stress. This is due to the nucleation of cement grains at their contact point by C-S-H formation during the dormant period before the setting initiates. 6. Conclusion Laboratory scale customized 3D printer developed in this study indicates that the prototype printer would only be useful to optimize motion control of the machine, to study the material properties of the printed objects, and to understand the dispensing mechanism. However, design for industrial application will need to establish a relationship between screw speed and feed rate, to avoid defects such as discontinuity and clogging. The dosage of superplasticizer needed to achieve the similar flow value increases as a/b increases. This is due to the reduced water content in the mixtures with higher a/b (aggregate to binder ratio). The plastic viscosity increased by about 35 % when a/b increased from 0.75 to 0.9. With a lower superplasticizer dosage, the yield stress increases with increase in VMA dose allowing extrudability, whereas flow does not gave definite trend. The flow was ranging from 160 to 225 mm which indicates dependency on the material type and packing density. Yield stress of mix is important to achieve buildability. Low yield stress value can lead to collapse of layers and will also prevent layer wise buildability. The optimum dose of polypropylene fibre was found to be 0.1 % by volume of concrete to achieve 3D printable mix without clogging or shrinkage crack. The open time is found to be about 12—15 minutes for the materials. A fresh mix of the material was prepared after 15 minutes considering its open time and maximum time interval between printing layers. Studies highlighted that both mix optimisation with different combination of cementitious binders and selection of optimum dosage of superplasticizer and VMA are very critical in achieving a 3D printable concrete. 3D printable concrete mixes adopted in recent years are with high amounts of cementitious binder and low amounts of aggregates which makes them prone to shrinkage cracking and poor durability. This is not in line with the principle of sustainability and durability. Therefore, investigating the application of 3D printable concrete with coarse aggregate and low binder contents is important in matching the goal of sustainable construction. REFERENCES 1. Khoshnevis, B.; Hwang, D.; Yao, K.-T.; Zhenghao, Y. Megascale fabrication by contour crafting. Int. J. Ind. Syst. Eng. 2006, 1. 2. Khoshnevis, B. Automated construction by contour crafting — related robotics and information technologies. Autom. Constr. 2004, 13, 5—19. 3. Bos, F., Wolfs, R.; Ahmed, Z.; Salet, T. Additive manufacturing of concrete in construction: Potentials and challenges of 3D concrete printing. Virtual Phys. Prototype. 2016, 11, 209—225 4. Wangler, T.; Lloret, E.; Reiter, L.; Hack, N.; Gramazio, F.; Kohler, M.; Bernhard, M.; Dillenburger, B.; Buchli, J.; Roussel, N.; et al. Digital Concrete: Opportunities and Challenges. RILEM Lett. 2016, 1, 67—75. 5. Khoshnevis, B.; Hwang, D. Contour Crafting. In Rapid Prototyping: Theory and Practice; Kamrani, A., Nasr, E.A., Eds.; Springer: Boston, MA, USA, 2006; pp. 221—251, ISBN 978-0-387-23291-1. 6. Khoshnevis, B.; Bukkapatnam, S.; Kwon, H.; Saito, J. Experimental investigation of contour crafting using ceramic materials. Rapid Prototype. J. 2001, 7, 32—41. 7. Jo, J.H., Jo, B.W., Cho, W. et al. Development of a 3D Printer for Concrete Structures: Laboratory Testing of Cementitious Materials. Int J Concr Struct Mater 14, 13 2020. 8. Jia Chao LIN, Jun WANG, Xiong WU, Wen YANG, Ri Xu ZHAO, Ming BAO, Effect of Processing Parameters on 3D Printing of Cement — based Materials, E 3S Web of Conferences 38, 03008, 2018. 9. Chao Zhang, Venkatesh Naidu Nerella, Anurag Krishna, Shen Wang, Yamei Zhang, Viktor Mechtcherine, Nemkumar Banthia, Mix design concepts for 3D printable concrete: A review, Cement and Concrete Composites, Volume 122, 2021, 104155. 10. A.V. Rahul, M. Santhanam, H. Meena, Z. Ghani, 3D printable concrete: mixture design and test methods, Cem. Concr. Compos. 97 (2018) 13—23. 11. A.V. Rahul, A. Sharma, M. Santhanam, A desorptivity-based approach for the assessment of phase separation during extrusion of cementitious materials, Cem.Concr. Compos. 108 (2020) 103546. 12. Z. Liu, M. Li, Y. Weng, T.N. Wong, M.J. Tan, Mixture design approach to optimize the rheological properties of the material used in 3D cementitious material printing, Constr. Build. Mater. 198 (2018) 245—255. 13. G. Ma, N.M. Salman, L. Wang, F. Wang, A novel additive mortar leveraging internal curing for enhancing interlayer bonding of cementitious composite for 3D printing, Constr. Build. Mater. 244 (2020) 118305. 14. Y.W.D. Tay, Y. Qian, M.J. Tan, Printability region for 3D concrete printing using slump and slump flow test, Compos. Part B Eng. 174 (2019) 106968. 15. S.C. Paul, Y.W.D. Tay, B. Panda, M.J. Tan, Fresh & hardened properties of 3D printable cementitious materials for building and construction, Arch. Civ. Mech. Eng. 18 (2018) 311—319. 16. T.T. Le, S.A. Austin, S. Lim, R.A. Buswell, R. Law, A.G.F. Gibb, T. Thorpe, Hardened properties of high-performance printing concrete, Cement Concr. Res. 42 (3) (2012) 558—566. 17. T.T. Le, S.A. Austin, S. Lim, R.A. Buswell, A.G.F. Gibb, T. Thorpe, Mix design and fresh properties for high-performance printing concrete, Mater. Struct. 45 (8) (2012) 1221—1232. 18. J. Kruger, S. Cho, S. Zeranka, C. Viljoen, G. van Zijl, 3D concrete printer parameter optimisation for high rate digital construction avoiding plastic collapse, Compos. Pt. B Eng. 183 (2020) 107660. 19. V.C. Li, F.P. Bos, K. Yu, W. McGee, T.Y. Ng, S.C. Figueiredo, K. Nefs, V. Mechtcherine, V.N. Nerella, J. Pan, G.P.A.G. van Zijl, P.J. Kruger, On the emergence of 3D printable engineered, strain hardening cementitious composites (ECC/SHCC), Cement Concr. Res. 132 (2020) 106038. 20. H. Ogura, V.N. Nerella, V. Mechtcherine, Developing and testing of the strain hardening cement-based composites (SHCC) in the context of 3D-printing, Materials 11 (8) (2018), 18. 21. I.M. Krieger, T.J. Dougherty, A mechanism for non-Newtonian flow in suspensions of rigid spheres, Trans. Soc. Rheol. 3 (1959) 137—152. 22. M.K. Mohan, A.V. Rahul, K. Van Tittelboom, G. De Schutter, Evaluating the Influence of Aggregate Content on Pumpability of 3D Printable Concrete, RILEM Book series, 2020, pp. 333—341. 23. V.N. Nerella, M. Nather, A. Iqbal, M. Butler, V. Mechtcherine, Inline quantification of extrudability of cementitious materials for digital construction, Cement Concr. Compos. 95 (2019) 260—270. 24. J. Kruger, S. Zeranka, G. van Zijl, A rheology-based quasi-static shape retention model for digitally fabricated concrete, Construct. Build. Mater. 254 (2020) 119241. 25. Ojha, P. N., Mittal, P., Singh, A., Singh, B., and Arora, V. V., “Optimization and evaluation of ultra-high-performance concrete,” Journal of Asian Concrete Federation, vol. 6, no. 1. Asian Concrete Federation, pp. 26—36, Jun. 30, 2020. 26. Arora V V., Singh B, (2016), Durability Studies on Prestressed Concrete made with Portland Pozzolana Cement, Indian Concrete Journal, Vol.90, No.8, 41—48, August, 2016. 27. V Patel, B. Singh, and V. V Arora, “Study on fracture behaviour of high strength concrete including effect of steel fiber,” Indian Concrete Journal, vol. 94, no. 4, pp. 1—9, 2020. 28. P.N. Ojha, A. Trivedi, B. Singh, A. K. N. S, V. Patel, and R.K. 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English pages 146 ABSTRACTS p. 12—14 Questions and answers. On the optimal grain size distribution in cements produced by closed-circuit grinding p. 14—15 Questions and answers. Comparison of efficiency of roller presses and vertical roller mills in grinding cement raw materials p. 16—18 V.A. Guz, E.V. Vysotsky Russian cement industry in 2022 The main indicators of the Russian cement market in 2021 and 2022 are shown in Table 1, and the data on cement consumption by federal districts is given in Table 2. The main indicators of the Russian cement market in 2021 and 2022 Figure 2021 2022 Change, % Production volume, thousand tons 60,067 60,789 1.20 Delivered, thousand tons 60,219 60,441 0.40 Railway transportation, thousand tons 26,178 25,119 –4.00 Import, thousand tons 1,957 2,202 12.50 Export, thousand tons 1,266 941 –25.70 Consumption, thousand tons 60,910 61,702 1.30 Net average producers ’ price for cement*, VAT and shipment excluded, rub/ton 4,040 4,896 21.20 Net average procurement price for cement*, VAT and shipment included, rub/ton 5,264 6,627 25.90 Market volume, bln. rub 320.6 408.9 27.50 * The source of data on cement producers ’ prices and cement purchase prices is the Unified Interdepartmental Information and Statistical System of the Russian Federation. Table 2 Cement consumption by Federal districts of the Russian Federation in 2021 and 2022, kt Federal district 2021 2022 Change, % Russian Federation 17,784 18,107 1.8 Central 10,180 10,352 1.7 North-West 7,755 7,656 –1.3 South 6,178 5,892 –4.6 North Caucasus 5,689 5,805 2.0 Volga basin 5,638 5,497 –2.5 Urals 4,292 4,666 8.7 Siberia 3,393 3,727 9.8 Far East 60,910 61,702 1.3 In 2022 Russia produced 60.8 Mt of cement. It was produced by 10 corporations, 51 cement plants, 6 grinding and mixing plants. About 60% of the products were produced using energysaving technologies, which is 2.2 times more than 10 years ago. The 5 top cement producers account for more than 62% of production. The 10 major companies control 89% of the cement market. Cement production in Russia in 2022 increased by 1.2%, to 60.8 Mt; cement shipments - by 0.4%, to 60.4 Mt. In 2022, 0.9 Mt of cement was shipped outside Russia, while 2.2 Mt was imported into the country. The cement output as a whole in 2022 increased by 1.2 %, while in the Q4 2022 it decreased by 11.1 %. In 2022 the share of additive-free Portland cement production increased in the total cement output from 63.0% to 64.0%, while the share of blended Portland cement decreased from 32.5% to 30.6%. Only the production of blended Portland cement decreased (by 961 kt, or 4.9%, to 18,571 kt). Additive-free Portland cement production increased the most in absolute terms (by 1,062 kt, or 2.8%, to 38,918 kt). The maximum growth in cement production in 2022 was achieved in the Far Eastern Federal District (by 347 kt, or 10.8 %, - to 13,461 kt) and the North Caucasus Federal District (by 326 kt, or 14.2 %, - to 2,611 kt) (Table 3). The biggest decline in production was observed in the Siberian (by 152 kt or 2.3 % - to 6,422 kt) and the Volga (by 110 kt or 0.8 % - to 13,351 kt) federal districts. The import of cement in Russia in 2022 increased by 12,5 % up to 2202 kt. The main cement-supplying countries to Russia were Belarus - 1,521 kt (17.3% more than in 2021), Iran - 310 kt (twice as much) and Kazakhstan - 205 kt (16.2% less). Imports of cement by water transport rose to 383 kt in 2022, or 39.5%, and accounted for 17.4% of all imports. Suppliers of cement by water transport during this period were Iran - 310 kt (81.0%), Turkey - 44 kt (11.4%) and Egypt - 29 kt (7.5%). In 2022 the Russian Federation imported 1,394 kt of cement by rail (15.7% more than in 2021), or 63.3% of total imports. Cement was delivered in Russia by rail from Belarus - 1096 kt or 78.7%, Kazakhstan - 205 kt or 14.7%, and the DNR - 92 kt, or 6.6%. In 2022, import of cement by road decreased by 11.0% (to 425 kt) and accounted for 19.3% of all imports. The volume of exports of cement from the Russian Federation in 2022 increased by 25.7%, to 941 kt. The main consumer countries of Russian cement in 2022 were Kazakhstan - 649 kt (24.6% less than in 2021), Belarus - 190 kt (40.0% less), Georgia - 73 kt (3 times more) and Azerbaijan - 14 kt (19.0% more). The amount of cement exported from Russia by rail in 2022 decreased by 27.1% to 784 kt, accounting for 83.4% of total exports. 158 kt of cement was exported from the country by road (2.6% more than in 2021) - 12.8% of all exports. In 2022, cement consumption in Russia increased by 1.3% (mainly due to the high performance achieved in Q1) to 61.7 Mt. p. 20—21 Ye.N. Botka Dry building mortars market in Russia: the results of 2022 and its prospects The article analyzes the results of the dry mortars industry in 2022. The modified mortars market in Russia, despite the difficulties, shrank by only 3%. The growth in the Q1 (12%), followed W O R L D C E M E N T N E T W O R K C O N F E R E N C E In association with 4–5 JULY 2023 HILTON BOMONTI ISTANBUL TURKEY For registration please visit www.worldcementnetwork.ae

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English pages 148 consequences that their use can entail is given. The use of high-molecular-weight polyethylene as a material for lining hoppers of reloading units, as well as the advantages and limitations of this method of preventing buildup are described. p. 90—97 V. Grosskopf Fire and explosion protection of coal grinding systems. Part I Despite the decarbonization trend in the cement industry, which involves replacing natural fuels with alternatives, coal grinding plants are widely used, and the task of ensuring their explosion and fire safety is unlikely to lose importance in the foreseeable future. At the same time, protective systems supplied to the facilities of the industry do not always allow to solve these problems successfully. This article describes the means of protection of coal grinding plants against fires and explosions, the factors on which their effectiveness depends, and the ways to improve it. p. 104—111 L.D. Shakhova, R.A. Kotlyarov, E.S. Chernositova On the mechanism of action of cement grinding aids The paper offers a theoretical substantiation of the mechanism of action of additives during cement grinding caused by the removal of surface electrostatic charges. The interrelation between the surface conductivity of cement particles and the class of organic compounds is established. Statistical methods were used to prove the influence of the type of the additive introduced and the mineralogical composition of the clinker on the dielectric resistance of cement particles and the fluidity of the powder. The results of the experiment and large-scale industrial practice are consistent with the proposed assumption about the possibility of removing electrostatic charges and regulating the fluidity of cement powder with the help of technological additives prone to polarization. © PetroCem Ltd. Reprinting of any materials from the journal is possible with written permission of Editorial Board only. If you are interested in having any articles of our journal translated into any language, please contact our Editorial Office at: Tel: +7 (812) 242-1124 E-mail: [email protected] by a moderate decline (by 3-4%) in the Q2 and Q3. A significant decline (-17%) was observed only in October-December. The decline in the retail segment was more significant, while the market demand was supported by large and medium construction companies. The versions of the market dynamics forecast for 2023-2025 are formulated. p. 70—71 A.S. Tomilov Digital products in the cement industry: choices and sources of benefits The benefits of high-tech solutions in continuous production are discussed. Information is given about the concept of Industry 4.0, digital products, and the positive factors in the cement industry that set the bar high for the application of manufacturing data. A successful example of the integration of a digital assistant cement mill operator in a plant is described. p. 72—75 O.N. Kaigorodov, V.M. Glukhovsky Alternative waste fuels: technologies and equipment The article discusses the prospects of alternative fuel (RDF) production from wastes and its use at cement plants in accordance with the state program "Alternative fuel use from waste in industrial production for 2022-2030". Experience in reducing moisture content and improving the quality of RDF obtained by the authors in the implementation of projects on drying RDF from solid municipal and wood waste for metallurgical and cement plants, respectively, is described. Information is given about a project currently being implemented for the construction of a line for receiving and dosing the RDF from MSW into the decarbonizer of a cement kiln of a dry production process. p. 76—79 A.M. Grinevsky Import substitution with proven efficiency Working in the interests of industries having harmful emissions, OOO Industrial Vostok Engineering offers technical solutions for removal of solid, aerosol, flue and gas components from process equipment and the working area. The company manufactures and supplies high quality equipment for aspiration and gas cleaning systems, including basic, additional and nonstandard equipment, as well as complex products from heat-resistant carbon steel, alloyed steel and titanium alloys. p. 81—85 M.S. Kazakov, O.L. Liferova, A.R. Pulina Digital technologies in mining operations The article describes the potential of the tools of nanoCAD GeoniCS software package for processing information during mining operations. The software package registered in the Uniform Register of Russian Programs for Electronic Computers and Databases allows to use efficiently digital technologies during surveying work. p. 86—87 M.A. Dgebuadze Bulk materials handling RBL-REI (France) has developed and put into operation a belt conveyor with a unique technical solution - a loop system. This improvement makes it possible when transporting material to pass a sharp turn of the route without the need to install two conveyors instead of one. p. 88—89 O.Yu. Stepuk Reducing the number of repairs of reloading devices The article describes the reasons for the problem of raw materials sticking to the walls of the handling devices of transportation lines and provides data on the frequency of this phenomenon at factories. The information about the standard ways of tackling material adhesion and the negative