Lump lime and iron ore are generally used in BOF as flux and cooling material respectively. Owing to high melting point, poor dissolution property, fines generation and hygroscopic nature of lump lime, delay in process and operational complexities are generally encountered. On the other hand, iron ore charging creates slag foaming. In order to alleviate the above problems and to utilize waste materials, fluxed iron oxide pellets containing waste iron oxides (ϳ70 %) and lime fines (ϳ30 %) were prepared and subsequently strengthened with CO 2 gas treatment. This carbonated fluxed pellets exhibited very good CCS (30 kg/pellet) and DSN (150), suitable for cold handling. The performance of this pellet has been assessed in a laboratory scale bottom blowing converter for its specific use in BOF. The refining characteristic of a liquid bath, prepared with pig iron chips was studied using a laboratory scale bottom blowing converter with three flux conditions namely fluxed pellet plus additional lime, iron ore lump plus lump lime and only lump lime. It has been observed that use of these pellets improves decarburization and dephosphorization, increases the metallic yield, decreases oxygen consumption and reduces foaming. Overall, the developed pellet shows very good application potential in basic oxygen steel making.

Ferrochrome (.62%Cr) and charge chrome (45-52%Cr) production using the submerged arc furnace (SAF) is an established practice in India. As the majority of Cr rich Indian chromite ore are friable in nature and available in fine form, utilisation of chromite fines for production of superior quality ferrochrome is essential. For this purpose, in the present study, the smelting of chromite pellets, briquettes, sinter and lump ore has been carried out in an electric arc furnace of 50 kVA. The energy consumption, yield, Cr recovery and quality of Fe-Cr produced have been compared for different Cr bearing materials. Sinters and pellets have found to be more suitable than briquettes and poor quality lump ore in terms of energy consumption and yield.

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The polymorphic transformation of the monoclinic ?-polymorph to the orthorhombic ?-polymorph of di-calcium silicate at around 500?C during cooling results in disintegration of slag. The slag generated, during the production of thermo mechanically treated steel in ladle furnace at M/s Tata Steel Limited, Jamshedpur, India, behaves in similar manner. An attempt has been made to prevent the crumbling of ladle furnace slag. The experiments were conducted in 10 kg air induction furnace. Various types of silica source were used to prevent the disintegration of ladle furnace slag by reducing the basicity and optimizing the additives amount. Apart from silica sources, other additives like borax and barium carbonate were also used to stabilize the ? phase. Present investigation reveals that disintegration of ladle furnace slag can be prevented either by addition of 0.2% boarx or 2% barium carbonate. Dust formation can also be prevented by decreasing the ladle furnace slag basicity to about 1.7. Toxicity Characteristic Leaching Procedure test, of the borax and barium carbonate treated slag samples, indicates that barium carbonate treated slag cannot be used for the dusting prevention as it contains high level of barium.