Process to Recover Iron Values from High-Alumina Indian Iron Ore Slime—a Bench-Scale Study

Abstract

In India, approximately 15–20% of Run of Mine (ROM) from any iron ore deposit is reported to slime dam as a byproduct of the iron ore beneficiation process. The proportion of iron ore slime to ROM will increase in the future, with a higher proportion of lean-grade ores in ROM. Furthermore, tonnages of iron ore slime will increase with increasing demand of iron concentrate. Presently, this slime is stored in a dam in the absence of beneficiation technology. A beneficiation flowsheet was developed at Tata Steel based on detailed beneficiation studies in the laboratory and bench scale. This process, on commercialization, will produce a concentrate of 2.2% alumina with 40–45% yield from slime of 7–9% alumina. The Fe content in the reject will be less than 40%, thus adhering to the regulatory norm. In this paper, results of bench-scale studies are discussed along with required characterization findings of feed and products. On commercialization, this process would provide solution to an urgent environmental concern of storing huge quantities of iron ore slime in the dam.