Manufacturing Process
Mining
The cement manufacturing process starts from the mining of limestone, which is the main raw material for making cement. Limestone is excavated from open cast mines after drilling and blasting and loaded on to dumpers which transport the material and unload into hoppers of the limestone crushers.
Crushing Stacking & Reclaiming of Limestone
The LS Crushers crush the limestone to minus 80 mm size and discharge the material onto a belt conveyor which takes it to the stacker via the Bulk material analyser. The material is stacked in longitudinal stockpiles. Limestone is extracted transversely from the stockpiles by the reclaimers and conveyed to the Raw Mill hoppers for grinding of raw meal.
Crushing Stacking & Reclaiming of Coal
The process of making cement clinker requires heat. Coal is used as the fuel for providing heat. Raw Coal received from the collieries is stored in a coal yard. Raw Coal is dropped on a belt conveyor from a hopper and is taken to and crushed in a crusher. Crushed coal discharged from the Coal Crusher is stored in a longitudinal stockpile from where it is reclaimed by a reclaimer and taken to the coal mill hoppers for grinding of fine coal.
Raw Meal Drying/Grinding & Homogenisation
Reclaimed limestone along with some laterite stored in their respective hoppers is fed to the Raw Mill for fine grinding. The hot gasses coming from the clinkerisation section are used in the raw mill for drying and transport of the ground raw meal to the Electrostatic Precipitator / Bag House, where it is collected and then stored and homogenised in the concrete silo. Raw Meal extracted from the silo (now called Kiln feed) is fed to the top of the Preheater for Pyroprocessing.
Clinkerisation
Cement Clinker is made by pyroprocessing of Kiln feed in the preheater and the rotary kiln. Fine coal is fired as fuel to provide the necessary heat in the kiln and the Precalciner located at the bottom of the 5/6 stage preheater. Hot clinker discharged from the Kiln drops on the grate cooler and gets cooled. The cooler discharges the clinker onto the pan / bucket conveyor and it is transported to the clinker stockpiles / silos. The clinker is taken from the stockpile / silo to the ball mill hoppers for cement grinding.
Cement Grinding & Storage
Clinker and Gypsum (for OPC) and also Pozzolana (for PPC) are extracted from their respective hoppers and fed to the Cement Mills. These Ball Mills grind the feed to a fine powder and the Mill discharge is fed to an elevator, which takes the material to a separator, which separates fine product and the coarse. The latter is sent to the mill inlet for regrinding and the fine product is stored in concrete silos.
Packing
Cement extracted from silos is conveyed to the automatic electronic packers where it is packed in 50 Kgs. Polythene bags and dispatched in trucks.
Electrical Power
For total power requirement of 90 MW (Jaypee Rewa Plant and Jaypee Bela Plant), we have
- CPP 1 - 25.0 MW
- CPP 2 - 25.0 MW
- CPP 3 - 37.0 MW
Four DG sets provide an emergency backup.