Recovery of Valuables From Low-Grade Iron Ore Slime and Reduction of Waste Volume by Physical Processing

摘要

Physical processing of low-grade (28% Fe) iron ore slime from Krivoy Rog province of the Ukraine is investigated. The slime is shown to have drastically different characteristics from those of Indian iron ore slimes. Effective recovery of iron values through physical beneficiation of the Ukraine slime is achieved. It is observed that a concentrate with 65% Fe can be obtained with 45% recovery of the iron value in the feed in spite of the low feed grade. A generic flow sheet for physical processing of the slimes is conceptualized and demonstrated. A comparison of processing results of the Ukraine slime is made against the processing data of Indian slimes. The iron recovery values for Jilling (37% Fe) and Chitradurga (49% Fe) slimes from India were only 32% and 38%, respectively. Substantial reduction in the waste volume (~50%) is achieved by processing. The reject volume is shown to depend on the feed grade as well as on the ultrafines content in the slime. Excellent rejection of silica and alumina is observed through physical beneficiation although significant iron loss in the tailings is unavoidable. Physical beneficiation does not have substantial cost implication and, being physical in nature, does not add to environmental pollution. Its efficacy toward addressing the environmental issues arising out of iron ore slimes while generating wealth from waste is demonstrated.