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The pellets production include four stages: raw materials preparation, formation of green balls or pellets, induration of the pellets, cooling, storage and transportation of pellets.
In the Grate-Kiln process the traveling grate is used to dry and preheat the pellets. Material moves on straight travelling grate till it attains the temperature of 800°C to 1000°C. Thereafter it is transferred to refractory lined rotary kiln for induration where the temperature is further raised up-to 1250 – 1300°C. At 800°C, the Magnetite iron Ore gets converted into Fe2O3 in an exothermic reaction. The liberated heat hardens the green balls which is helpful to withstand the tumbling impact in the rotary kiln. A circular cooler is used for cooling of the fired pellets.
Pelletizing grate kiln
