The principle of Grate Discharge grinding is nearly universally adapted in the cement grinding industry. Grate Discharge Ball Mills are the rule rather than the exception. Rod Mills for raw and finish grinding begin to enter the picture. Larger and larger diameter mills become common. Lengths tend to shorten. Cement grinding using Grate Discharge principles developed in the ore milling industry applied to the cement industry. This experience plus the years of manufacturing know how unquestionably qualify Grate Discharge grinding for the Cement Industry.
RAW CEMENT GRINDING
This phase of grinding may be either the wet or dry process, the end product going to a kiln. Material ground consists of limestone, cement rock, marl or marine shells along with secondary materials usually shale or clay. A typical raw mix consists of 75-85% limestone, 12-25% shale, the balance consisting of silica or quartzite and iron oxide. Exact proportioning is dependent upon their chemical properties before and after calcining to cement clinker. For good kiln practice the grind required is 88-92% – 200 mesh for standard cement, 99%-200 mesh for high early. Uniform kiln feed size helps reduce tendency to form kiln rings.
WET VS DRY Grinding of Cement
Wet grinding is generally more efficient ….Read more