Sintering of Dolomite in Shaft Kiln of Hindustan Steel Plant Rourkela

L.D. Oxygen steel converters are usually lined with tar-bonded sintered dolomite after suitability calcining and sintering treatments. The Plant of Hindustan Steel Ltd. at Rourkela, where two oxygen steel L.D. converters of 25 tons capacity each are in operation, have set up two shaft kilns for burning of dolomite at high temperatures using a mixture of coke oven and blast furnace gases for firing the kilns. One of the shaft kilns was reported that the dolomite materials did not descend uniformly owing to sticking and bridge formation at high temperatures. The calcined product at the discharged end was delivered in lumpy and powdery form –these lumps also subsequently were reported to have hydrated quickly. Such hydration occurred much more readily when the “burning” temperature was lower than the optimum needed.