Cement – one of the main materials at construction, this special knitting substance from mineral components which when hardening form very strong, solid material. Cement is produced from various raw materials depending on the region.
The main raw materials for production of cement
Cement is done of special cement clinker which represents result of roasting of the main mineral raw materials extracted in nature or made in the artificial ways. Clay and carbonate breeds can be raw materials for cement.
Clay breeds are a clay, loam, the loess, clay slate, lessovidny loams and other breeds. Clay at addition of moisture inflates and becomes plastic that is important for quality cement. All these types of clay breeds differ on the properties a little. For example, loam contains many sandy substances, and clay slates dense and firm, consist of plates, have smaller humidity. The loess porous and friable, incorporates quartz, feldspar and other materials.
Carbonate breeds include chalk, limestone, marl and other calcareous, carbonate and dolomitic materials. Depending on structure, properties and quality of these raw materials, cement with different features turns out.
For example, crystal breeds it is worse for production of cement as they enter interaction with other elements during roasting.
Most often for creation of cement use chalk which is easily pounded and crushed. Marl is applied to production of cement which is necessary at the device of fireplaces and furnaces: this material is transitional between clay and calcareous. Except the main raw materials, add additional ingredients which change properties of a product to cement.
It can be plaster, fluorite, sodium, apatite, a phosphite and other materials and also aluminous, clay-containing additives.
Production of cement
The first production phase of cement – production of clinker from the main raw materials by means of roasting. It is the most expensive stage as on extraction of materials about 70% of cost of production of cement leave. To find the necessary breeds, it is necessary to demolish (usually by means of dynamite) the top part of the calcareous mountain and to open a layer of breeds which usually meets at a depth of 10 meters. The extracted material is crushed, mixed with additives and burned. Further clinker is still crushed by heavy steel spheres while from it powder which needs to be dried up well is impossible, then other ingredients are added to it - it is the second stage of process of production of cement.