REDUCTION ROASTING AND Fe-Al SEPARATION OF HIGH IRON CONTENT GIBBSITE-TYPE BAUXITE ORES

摘要

Large reserves of high-iron content gibbsite-type bauxite ores have been found in China, which are characterized as relatively high iron oxides content, but low alumina content and A/S ratio. Aluminiferous minerals and ferrous minerals are fine or superfine in size, and conjoint and substituted with each other; therefore, physical beneficiation is not feasible due to extremely difficult liberation. In this study, reduction roasting and separation of iron and alumina had been investigated. The influences of reduction time, roasting temperature and magnetic separation were involved. The results indicate that a metallic iron concentrate with 93.3% total iron grade and non-magnetic product with 40% alumina content were obtained when a sample with 31.22% total iron grade and 26.35% alumina was processed. Metallic iron concentrate can be used as steelmaking burden, and alumina can be extracted from the non-magnetic product further.