This is where the cement manufacturing process begins. Limestone is the major raw material used for producing cement, and is excavated from the captive mines held by the organization. The quarrying activity is carried out employing opencast mining technique, following drilling and blasting. The excavated limestone is then transported to the clinker plants for crushing and grinding.
The limestone boulders extracted are crushed into the required feed size for grinding in a two stage process employing jaw crushers as well as impact/ hammer crushers.
The crushed limestone is then transferred to the stacker reclaimer site through belt conveyor and stacked in layers. The reclaiming machine further cuts the limestone and mixes the layers to reduce the variation in quality. The limestone is now ready for reclaiming and feeding to Raw Mill hoppers for grinding of raw meal.
Limestone along with laterite, clay and coke (Raw Mix) are fed to the Raw Mill via hoppers and a belt conveyor for fine grinding. The proportion mix is pre-determined depending on the quality of Clinker required and monitored using weigh feeders.
The ground Raw Meal is fed to a bucket elevator, which takes the material to a classifier, which separates fine and coarse particles. The latter is sent to the mill inlet for regrinding and the fine product is transported to the blending silos using screw conveyors, where it is stored and homogenized. Once completely homogenized, the raw meal is called Kiln Feed.
The Kiln Feed is transported to the Noduliser with the help of an air-lift. At this stage, water is sprayed on the feed (appx. 10%) to make nodules, which are then fed into the Vertical Shaft Kilns (VSK) through feed chute for burning and fusion. The temperature goes up to 1400°C in the burning zone. The nodules travel very slowly in the kilns. All the materials get fused here. After passing through the burning zone the materials start cooling slowly. Clinkerisation starts and the clinker finally comes out of the kilns. The clinker is then transferred to a storage yard using belt conveyors, which subsequently feeds the cement plant.
Clinker stored for a few days is ground in Cement Mills along with an appropriate quantity of Gypsum (for OPC) and Pozzolana materials (for PPC), which are extracted from their respective hoppers. These Ball Mills grind the feed to a fine powder and the Mill discharge is fed to a bucket elevator, which takes the material to a classifier, which separates fine and coarse particles. The latter is sent to the mill inlet for regrinding and the fine product is stored in RCC silos.
The cements produced by Reliance are stored in different concrete silos installed with different capacities. Depending upon the market requirements, the cement is loaded in bulk or packed in specially designed Reliance 50 kg bags with the help of conventional rotary packs or electronic packs, loaded on to trucks and finally dispatched to their destinations.