Abstract:
Chromite overburden (COB), considered as a waste material with 46% Fe and 0.8% Ni, is the only source of nickel in India. Iron and nickel from COB were recovered through reduction roasting, magnetic separation and smelting. In sintering, maximum Ni% was achieved at 1.0% S, 10% C inside and 10% C outside of the COB pellet. Ni was, further, enriched by smelting the magnetic fraction of sintered COB. XRD, SEM-EDS and chemical analysis of the feed material and products confirmed enriched Ni content in the ferronickel alloy. With the optimized parameters such as 12 min time, 1.2 basicity and 10% reductant, ferronickel alloy contains 8% Ni and 89% Fe with recovery of 87% Ni. It was possible to produce different grades of ferronickel, varying from 2 to 10% Ni.