Cement is typically made from limestone and clay. These raw materials are extracted from the quarry crushed to a very fine powder and then blended in the correct proportions.
This blended raw material is called the 'raw feed' or 'kiln feed' and is heated in a rotary kiln where it reaches a temperature of about 1350 C to 1500 C. The rotary kiln is a tube up to 200 meters long and perhaps 6 meters in diameter, with a long flame at one end. The raw feed enters the kiln at the cool end and gradually passes down to the hot end, then falls out of the kiln and cools down to form what is called 'clinker' (see clinker for more info). Clinker is typically composed of rounded nodules between 1mm and 25mm across.
After cooling, the clinker may be stored temporarily in a clinker store, or it may pass directly to the cement mill. At T3 International, we provide our clients with either products in bulk and packaged as well (cement is packaged in 50kg bags and jumbo bags as well).
The cement mill grinds the clinker to a fine powder. A small amount of gypsum - a form of calcium sulfate - is normally ground up with the clinker. The gypsum controls the setting properties of the cement when water is added. We provide OPC 32.5, 42.5, 52.5 and class "G" as well. You can view the specification of all our products by clicking on the appropriate files.
Please see the graph below for the production process: