Experimental study on flotation desulfurization process of high sulfur coal in Yunnan province

Coal and pyrite are the valuable minerals that can be recycled in the raw coal with high ash and sulfur content in Shijiazhai mine,Luoping country,Yunnan province.According to the characteristics of the coal sample,a flotation flowsheet is proposed to process the ore in this paper.The coal is separated by depressing the pyrite firstly.Then the pyrite is activated and flotated.The small-scale closed circuit experiment is conducted based on the optimization of reagent scheme and dosage.A coal concentrate with a yield of 37.18%,assaying 41.10% C and 5.38% S at a C recovery of 83.05%,and a S concentrate with a yield of 6.18%,assaying 9.04% C and 42.49% S at a S recovery of 30.56% are obtained by the experiment.Conditional test results show that collector diesel oil with stage addition can greatly improve the recovery of coal concentrate and decrease beneficiation cost in the condition of optimizing calcium oxide dosage.Comparing the closed circuit flotation tests,it seems that the S concentrate of high grade and yield can be obtained while coal is only as far as possible flotated cleanly in coal flotation operation.