How much clay is in cement

Manufacturing process of cement

  • Raw material extraction

    The most important raw materials for the production of cement are limestone, clay and marl. They are extracted in quarries by blasting them or with heavy equipment by cracking them.

  • Transport of the raw material

    A wheel loader loads a dump truck. This transports the raw material to the crushing plant in the quarry.

  • Shredding of the raw material

    In the crushing plants, the rock is roughly crushed to the size of road gravel.

  • Transport to the factory

    The raw ballast is transported to the ballast hall of the cement works on conveyor belts, by cable cars or railways and, in exceptional cases, by trucks.

  • Homogenization

    In the ballast hall of the cement works, the raw ballast is stored in mixed beds at the same time homogenized (evened out).

  • Drying and raw grinding

    The required raw mixture of crushed stone and the required aggregates (quartz sand and iron ore) is produced using metering devices. The mixture is ground fine in bowl or ball mills and dried with the hot exhaust gas from the burning process at the same time before it gets into the raw meal silos.

  • Burn

    The burning of the raw meal to cement clinker at 1,450 ° C - the most important process in cement production - takes place in Lepol ovens or in heat exchanger ovens, which work according to different processes and differ mainly in the preparation and preheating of the material to be burned.

  • Cooling the clinker

    After firing, the clinker is cooled and stored in clinker silos.

  • Cement grinding

    Cement mills grind the clinker with the addition of gypsum, anhydrite and, in some cases, other additives (e.g. limestone, blast furnace slag or fly ash) into cement.

  • Loading and shipping

    Cement is mainly supplied as loose (unpackaged) goods and loaded onto road or rail vehicles or ships via terminals.

  • Packaging / bagged cement

    A small portion of the cement reaches the customer as bagged goods, filled by Rotopackers and stacked on automatic palletizing systems.