Abstract: Since the iron ore concentrator of Masteel Luohe Iron Mine was put into operation,there are such problems needed to be solved,that the capacity of stageⅠball mill can′t meet the design requirements,the sulfur content in the iron concentrate of LIMS is over the standard,the separation index of the hematite concentrate is poor and the copper in the sulfur concentrate is not recycled.In order to solve the problems above,on the basis of the whole process investigation on the grinding and dressing system in the dressing plant,the grindability of the ore was researched to verify the processing effect in the laboratory tests with referencing the process parameters of field sulfur flotation,LIMS,HIMS and gravity separation operation.The separation process of copper and sulfur in the sulfur concentrate which contains copper was studied.According to the research results,the improvement measures for the outstanding problems in the dressing plant were put forward.After the completion of sulfur reduction in the magnetite concentrate and copper-sulfur separation,the S content of the field magnetite concentrate will be reduced from 0.51% to less than 0.30%;copper concentrate separated from sulfur concentrate with production rate of 0.82% ( to sulfur concentrate),Cu grade of 17.51%,recovery rate of 59.54% (to sulfur concentrate) was obtained.

Key words: Sulphur flotation,LIMS, HIMS,Gravity separation, Separation of copper and sulfur, Grindability, Mechanical inclusion