Utilisation of Iron Oxide Waste through Cold Bonded Pelletisaion

Abstract

India is endowed with large reserves of iron ore. Mech-anised mining generates considerable amount of iron ore fines. Additionally, large quantities of slimes are generated from washing of ores at mine-heads.Further, many coal based rotary kiln sponge iron plants are generating huge quantities waste fines within their works. In addi-tion, in integrated steel plants, a lot of iron oxide rich wastes are generated. Some of them are generated mixed with carbon particles or hydrocarbons (oil, etc.). All these pose problems both with respect to economy and ecology. In RDCIS, work was carried out to pelletise iron ore fines after mixing with up to 10% non-coking coal, and utilise these composite pellets in coal based rotary kiln DR plants. These pellets were cold bonded so that carbon is retained for- reduction purpose. After extensive laboratory investigations, these pellets were tested in a rotary kiln DR plant.Composite pellets reduced much faster as compared to lump ore.Metallisation level of over 90% was achieved consistently. Kiln productivity increased and energy consumption decreased substantially.The plant trials established the suitability of composite pellets for DRI production in rotary kilns.