Exploration and application of the technique for increasing the percentage of lump coal in run-of-mine of Chengzhuang Mine

Lump coal is a product that can bring a highest comprehensive economic benefit for the mine. For increasing the percentage of lump coal, the following technical measures are adopted: optimization of fully-mechanized face equipment and working process; upgrading of various belt conveyor transfer points; and installing external spiral chute for underground coal silo. Through the adoption of the measures, the accumulative percentage of coarse raw coal feed to coal preparation plant is increased by 4.95 percentage points, yielding considerable economic returns.