Processing Of Gangra Iron Ore Using End-Of-Life Tyres as Reductant

Abstract

ArcelorMittal Liberia is actively mining the Mount Gangra iron ore deposit. Mt Gangra is primarily underlain with Precambrian rocks, including Banded Iron Formation (BIF) with significant ore reserves. Lowgrade and transition ores are found in Gangra. By removing the silica, these ores can be beneficiated to high-grade iron metals. The oxide's iron content ranges from 50<%Fe<58%, fresh rock 20<%Fe<35%, transition high-grade from 42<%Fe<50%, and transition low-grade from 35<%Fe<42%. Previous DSO mining methods have resulted in an enormous lowgrade and transition stockpiles. End-of-Life Tyres (ELTs) generated by haulage trucks are stockpiled and there is no recycling strategy in place in Liberia. Hence, this study aims to beneficiate the lowgrade and transition iron ores using ELTs as reductants. Utilising iron oxide mined from Mount Gangra, the recycling of ELTs was investigated. The carbonaceous material was combined with iron oxide, binder, and water to create composite pellets with different compositions (70 wt% ore, 75 wt% ore), ELT, and binder. Microwave irradiation of (ore-ELT composite pellets) was used for the reduction studies. After reduction at varying times, the reduced material was weighed to ascertain the weight of the reduced pellet and the per cent weight lost. The results indicate that carbonaceous material (generated from ELTs) is a good reductant for the formation of iron metal. The study, using XRD and SEM-EDS reveals that Gangra lowgrade and transition ores contain hematite and reactive silica, which react with carbon from ELTs to produce metallic iron, ferrosilicon, and silicon carbide.