Coal Desliming Using Annular Rinse Water Hydrocyclone

Abstract

The separation of fine coal can be improved by pre-desliming, which was significantly enhanced when fine coal was processed using a Falcon concentrator, and <45-μm coal slime was removed. Ultrafine classification tests using Krebs classification cyclone with annular rinse water showed that the increase in feeding concentration negatively affected the efficiency of classification while increasing the classification size because the settling was hindered by the high underflow concentrations. The optimization experiments with response indicators of classification efficiency based on orthogonal design using Design-Expert software indicated that the optimal classification efficiency reached 91.32% with a feeding pressure of 0.03 MPa, a rinse water pressure of 0.02 MPa, and a feeding concentration of 12.5%. Meanwhile, the classification size was 49.99 μm, which agreed well with the predicted value.