Various stages in wet process of manufacturing of cement:
The manufacturing of cement by wet process can be divided into three stages.
Stage-I Mixing of raw materials: In this stage, 10% of chalk and 30% of clay which contains some sand, iron Oxide, magnesia, etc. are crushed, grounded and mixed uniformly. Generally theingredients are crushed in a crushing mill and carried by water into large tankswhere it is allowed to settle for weeks. The water is then taken out and the slurryis then dug out and dried in an oven.
Stage-II Burning: Burning of the above dried slurry is carried out in a rotary kiln. Kiln rotates At a rate of 1RPM about its longitudinal axis. The slurry is injected the upper endwhereas the hot gasses are forced through the lower end of the kiln. As the slurrymoves down nodules are formed, which after gets converted into clinkers. Thecooled clinkers are collected into containers of suitable size.
Stage-III Grinding: In this process, the clinkers are ground to very fine powder in ball mills andTube mills. The powder is then spread over a dry floor for some days for airSlacking and then 5% Gypsum is added to improve the quality of cement. TheFinely ground cement is stored in silos. It is then weighed and packed in bags of50kg by weight.