Optimization of the process for treating the extremely difficult-to-wash coal at Tengqing Washery

Tengqing Coal Washery is facing the trouble of having a high loss and inconsistency of clean coal product. Based on the actual capacity of the existing washing system and the results of fact-finding site investigation,and analysis of properties of raw coal feed and cleaned products,an optimized washing scheme is developed. This involves first crushing of the ＞ 25 mm coarse raw coal and the 25-13 mm middlings respectively down to a size of ＜ 13 mm for liberation of the intergrown constituents and then rewashing of the crashed middlings. After optimization of the washing process,the yield and output of clean coal are expected to rise respectively by 3. 27 percentage points and 5 890 t/a,an additional annual sales income of over 2 million yuan can be gained,bringing forth a favorable economic benefit for the plant.