Keywords: basic oxygen furnace, BOF sludge, dust, recycling, LD sludge utilisation, slurry, pelletisation, iron oxide, lime, iron ore sintering, steel making, moisture content, raw materials, India
Conservation of iron and lime bearing raw materials by recycling of basic oxygen furnace (BOF) sludge in iron ore sintering
Basic Oxygen Furnace (BOF) sludge is one of the by–products generated during process of steel making. It has very high level of iron oxide and lime content. However, the high moisture content of the BOF sludge (35–40%) is a major obstacle in its recycling. Internal recycling of the BOF sludge, with or without pre–treatment, is an integral feature of integrated steel plants in advanced countries. However, in India, the impetus for recycling started much later and is primarily driven by potential economic gains. Efforts have been made to recycle it back in BOF as well as in sinter plant and blast furnace after proper drying and agglomeration. The present paper, through laboratory investigations, evaluates the influence of different methods of sludge addition on iron ore sintering and saving of iron and lime bearing raw materials due to recycling of different amount of BOF sludge.