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Iron ore sintering is an extremely complex process involving fuel combustion to generate heat and reducing gases like CO. This heat allows physicochemical, solid and solid-liquid reactions to form liquids of complex components as fuel particles are consumed and cooling processes allow the formation of solid mineral phases. At JSW coke breeze from coke ovens is used as solid fuel in sinter. The properties (size) of the solid fuel play a very important role in determining the sinter microstructural properties and sinter quality. The microstructure of the sinter is a basic necessity and also the first step towards establishing the structural property relationship. Microstructural studies have been carried out to understand the effect of coke breeze particle size on sinter microstructure and sinter properties. The present paper is an attempt to understand and correlate the physical and metallurgical properties of sinter with varying size of the coke breeze particle in sinter mix. It was observed that as the proportion of coke breeze below 3 mm in the sinter mix increased from 53?0 to 90?0% the calcium ferrite phase increased, the number of bigger size pores decreased, and thereby decreased the reduction degradation index (23?15 mm) of sinter from 39?7 to 23?5%. Superior sinter properties were obtained with the 23 mm coke breeze size ,90% in the sinter mix.

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Pellet plant (4?2 MPta capacity) of JSW Steel Ltd imports iron ore fines from different mines to produce pellets for its Corex and Blast Furnace plants. The pelletisation process involves drying the ore fines to reduce the moisture content to less than 1%, grinding in open circuit ball mills to get required fineness. To produce good quality of pellets certain additives are important and limestone is employed for modifying the pellet basicity. Iron ore fines of 210 mm size and limestone are ground together in a ball mill to get sufficient fineness for the balling process. However, as limestone is harder than iron ore fines the z100 mesh size limestone particles is higher than required and not all the limestone is fully consumed in the reaction for melt formation. Microstructural studies were conducted under a Leica DMRX polarized microscope at different level fineness (2325# 2 56, 58 and 60%) to investigate its effect on the pellet quality. The cold crushing strength of the pellet improved from 203 to 220 kg p 21 with increase in fineness. With increase in percentage of 2325# particle size in the ground product RDI of the pellet decreased from 13?8 to 11?9% with increased melt formation from 5 to 9%. With increase in fineness 2325# from 56 to 60% the 150 to 500 mm size pores decreased from 51?8 to 13?6%.