The potential of obtaining ilmenite concentrate from titanomagnetite ore tailings

Abstract

Titanomagnetite and ilmenite are the primary titanomagnetite ore minerals of the Gusevogorsk deposit. Due to its low mass fraction in the ore (approximately 1 %), ilmenite is treated as waste during ore processing. The purpose of this research was to assess if titanomagnetite ores of the Gusevogorsk deposit could be used to obtain highgrade ilmenite concentrate with a TiO2 mass fraction of at least 48 %. With the expected low yield of the secondary (ilmenite) con-centrate, the tailings processing system at the existing concentrator should be simple and should not include regrinding of non-magnetic products downstream of wet magnetic separation. This is a mandatory precondition for the profitable production of ilmenite concentrates. Taking into account the low content of ilmenite in the original ore, a combined system was selected, based on the technologies of magnetic and electric separation and gravity concentration. The process shall consist of six successive operations, namely: high gradient magnetic separation, wet magnetic separation, fine screening, table concentration, drying, and electric separation. Pilot processing of wet magnetic separation tailings without additional grinding delivered high-grade ilmenite concentrates with a mass fraction of titanium dioxide of 48.66 % and a yield of 0.13 % to ore. With lower yields, higher-grade concentrate (50.87 % TO2) may be obtained. Titanomagnetite middlings were also produced, with a mass fraction of iron of 52.12 % and a yield of 0.46 % to ore. Their further grinding and processing will additionally improve the titanomagnetite concentrate yield. A final conclusion on the applicability of the technology designed for obtaining ilmenite concentrate from titanomagnetite wet magnetic separation tailings should be made following a respective feasibility study.