ABSTRACT
The production of Portland cement involves the firing (burning) of calcareous material (normally limestone, sea shells etc.) with an argilla ceous material (clay, an aluminosilicate). The solid raw materials are crushed and mixed in ball mills, and then heated in a kiln to about 1500 °C. The firing results in the formation of a clinker which consists of a number of compounds which set or harden when the clinker is ground to a fine powder (cement) and then mixed with water.
