The most common raw materials used for cement production are limestone, chalk and clay. The raw materials are crushed, ground, and proportioned so that the resulting mixture has the desired fineness and chemical composition for delivery to the pyroprocessing systems. More than 1.5 tons of raw materials are required to produce one ton of portland cement. In dry processing the materials are ground into a flowable powder in horizontal ball mills or in vertical roller mills.Clinker is produced by pyroprocessing in large kilns. Once the clinker is formed in the rotary kiln, it is cooled. After cooling, the clinker is stored in the clinker dome, silos, bins, or outside. To produce powdered cement, the nodules
of cement clinker are ground to the consistency of face powder. Coarse material is separated in a classifier that is re-circulated and returned to the mill for additional grinding to ensure a uniform surface area of the final product.
Process Flow Diagram
Energy Efficiency Improvement:
Activity Name
Existing Technology replaced
Efficient Process
/Technology penetrated
Energy Savings (ES) GJ/year
Monetary Equivalent of ES (Million INR/year)
Investment Cost (Million INR)
Simple Payback (Months)
GHG Emissions reduced (tCO2e/yr)
Grinding
Raw mill
Replacing low efficiency fan with a high efficiency one
