DETERMINATION OF OPTIMUM CONDITIONS TO REMOVE SULFUR AND PHOSPHOR FROM GOL-E-GOHAR IRON ORE CONCENTRATE

Gol-E-Gohar iron complex is located 50km southwest of Sirjan City, Iran. Its concentrate contains sulfur and phosphor with grades of 0.5%S and 0.08%P which are higher than the steel industrial permitted limit of 0.1%S and 0.05%P. Pyrite and apatite are the main sources of sulfur and phosphor. In this work, it was attempted to decrease the S and P percentages of the concentrate using the flotation approach. In reverse flotation with the presence of xanthates, pyrite floated and fine apatite particles were conducted with water. The results of mineralogical studies indicated that the main minerals in the sample were magnetite and hematite and others were goethite, chlorite, pyrite, calcite, quartz and apatite, chalcopyrite and pyrotite in low amounts, and -75+53 microns was the pyrite liberation size with a degree of 65%. The effect of different parameters such as type and doze of collector, frother and depressant, solid content, pH, impeller speed, frothing time, conditioning time and desliming on sulfur and phosphor removal were investigated. The best results were achieved with desliming. The collector, frother and dispersant were 50g/t of KAX, 60g/t of MIBC and 200g/t of sodium silicate, pulp pH=8, and 6 minutes for conditioning time. Under the best conditions, with desliming, a concentrate with acceptable grades of Fe (70.24%), S (0.041%), and P (0.043%) were obtained. The recovery for Fe was 95.11%, and for sulfur removal, 92.24%.