渣中铬矿球团初期熔融现象的研究

Study on the Smelting Phenomenon of Chromite Pellets in Slag

利用管式炉对单个球团加入初期的升温过程、加热速率及其影响因素进行了理论和实验研究。建立了传热数学模型。实验结果与理论计算相符。1500—1568℃下球团(25℃)加入后至反应开始时间为50—80s,增高渣温、预热球团和强化搅拌可缩短至15s左右。研究结果对开发强搅拌下转炉铁浴型反应器进行铬矿、锰矿熔融还原新工艺具有参考意义。

The heating up process of a single chromite pellet immersed in the slag bath prior to its smelting reduction has been investigated theoretically based on the heat transfer principle and experimentally in the laboratory. A mathematical model for the heating up process of a single pellet has been developed. Predicted data by this model are in good agreement with data obtained experimentally. It has been found that the time for heating up the chromite pellet from its charging temperature (25 ℃) to the reaction temperature (1200℃) in a slag bath of 1500-1568℃ was 50-80 s. The slag shell formation and factors influencing the heating up process have been investigated by the mathematical model. The heating-up time can be reduced to 15 s by raising the slag temperature, preheating pellets and stirring the slag bath. Results obtained in present work are useful in the consideration to develop the smelting reduction process of chromite, manganese ores and iron ores or their pellets in the iron bath reactor.