The sample for the fly ash was characterized by size analysis,X-ray diffraction and X-ray fluorescence.This test has carried on the flotation machine to test sample exploring experiment and process optimization. Within the range studied,the collecting agent is 400 g/t,the optimum frother dosage is 400 g/t,concentration of pulp is15%,froth thickness is about 3cm and circulating pressure is 0. 10 MPa.Get the productivity of tailing is 75. 99%,a cleaning ash with 1. 17%; and the productivity of clean coal is 2...