Enhanced gravity separator in processing Indian iron ore slime

摘要

The present practice of beneficiation of iron ores in India produces lumpy ores (for blast furnace), classifierfines(forsinter plant) and slimes (below 150 urn) which are stored in tailings pond. The estimated generation of slimes is 10-25 % of the iron ore mined amounting to 18 million tonnes per year. Besides the loss of iron values, it poses environmental hazard. From resource management view point and also from environmental management view point, processing of the slime is inevitable. In the present paper, the slime sample was subjected to concentration using enhanced gravity separatorsuch as Falcon concentrator for its enrichment. The effects of major important variables e.g. bowl rotation frequency; back water flow rate, % solid and mesh of grind of feed sample were studied on the process performance. Increasing the rotation frequency of the Falcon bowl, enable more material to the underflow by increasing the yield, whereas, the iron content decreases steadily. The increase in the back water flow effectively removes the clay materials from the underflow at the expense of the yield. Similarly, increasing the % solid concentration in the feed produces a product marginal higher yield with decrease in Fe content. With increase in mesh of grind of the feed sample, Falcon produced a better grade concentrate at the expense of the yield due to better liberation at the finer size. Results show that EGS/Falcon can be used for processing Indian iron ore slime and producing pellet grade concentrate.