Recovery of ferrochrome values from flue dust generated in ferroalloy production – a case study

Abstract

Ferrochrome is usually produced by the reduction of chromite ore in a submerged arc or direct current furnace. The production process generates a large quantity of flue dust that contains potentially valuable components, such as ferrochrome, iron and carbides. In many instances, valuable chromite minerals are misplaced in the flue dust along with the slag forming minerals during the reduction process. In the present investigation, mineral beneficiation techniques were used to recover the ferrochrome material in lieu of the pyro‐ and hydrometallurgical techniques, which are currently being practiced. The experimental results show that gravity concentration could enrich Cr values in the concentrate to 42·2% with 37·3% yield from flue dust material containing 37·3%Cr. The beneficiation techniques could only marginally enrich the ferrochrome values because of the complex association of the metallic phase with the slag forming phases.