Cement is known as Ordinary Portland Cement (OPC). It is used as a perfect binding material across the world. It will also commonly available for material for general use around the globe, an ingredient to mortar. Cement is produced from limestone by grinding, Calcining then grinding to produce a fine powder, which intern is mixed with gypsum to retard setting time. The basic cement clinker is a hydraulic mass composes two third mass of calcium silicate (CaO.SiO2), and the rest consists of aluminium and iron associates and other materials, with the ratio of CaO to SiO2 to be not less than 2, and magnesium oxide to be not more than 5% by mass.
Cement is manufactured through a closely controlled chemical combination of calcium, silicon, aluminium, iron and other ingredients Common materials used to manufacture cement include limestone, shells, and chalk or marl combined with shale, clay, slate, blast furnace slag, silica sand, and iron ore.
Manufacture it involves the following steps
- Mixing of raw material
- Storage and packaging
Composition-Portland cement consists essentially of compounds of lime (calcium oxide, CaO) mixed with silica (silicon dioxide, SiO2) and alumina (Aluminium oxide, Al 2O 3). The lime is obtained from a calcareous (lime-containing) raw material.