含钛高炉渣高温碳化过程出渣口耐材侵蚀研究

Study on erosion of slag outlet refractory during high-temperature carbonization of titanium-bearing blast furnace slag

针对含钛高炉渣高温碳化过程出渣口位置耐材侵蚀严重的问题,本文采用电子显微镜对耐材侵蚀样品进行显微结构的表征与分析,同时使用FactSage软件计算耐材与高炉渣在不同温度下的反应情况,以揭示耐材的侵蚀过程。研究结果表明:冶炼初期出渣口处的镁碳砖不断受高温熔渣侵蚀或冲刷的作用而损耗。当镁碳砖因蚀损减薄至一定程度时,水冷炉壁对炉衬侧熔渣进行有效降温,熔渣内的高熔点物质析出,降低耐火材料表面熔渣的流动性,同时填补耐材侵蚀产生的孔洞,从而有效地减缓熔渣对炉衬的侵蚀速度,阻止炉衬进一步被熔渣侵蚀。根据研究结果,本文建议出渣口采用铜冷却壁的方式提高冷却强度,促进高熔点物质析出,以减缓侵蚀速率,提高使用寿命。

In view of the serious erosion of slag outlet refractory during the high-temperature carbonization of titanium-bearing blast furnace slag, the microstructure of refractory erosion samples is characterized and analyzed by electron microscope, and the reaction between refractory and blast furnace slag at different temperatures is calculated by FactSage software to reveal the erosion process of refractory. The results show that the magnesia carbon brick at the slag outlet in the early stage of smelting is continuously eroded or scoured by high-temperature slag. When the magnesia carbon brick is thinned to a certain extent due to erosion, the water-cooled furnace wall effectively cools the slag at the lining side, and the precipitation of high-melting point substances in the slag reduces the fluidity of the slag on the refractory surface, at the same time, fills the holes caused by erosion of refractory materials so as to effectively slow down the erosion rate of the slag on the lining and prevent the lining from being further eroded by the slag. According to the research results, it is suggested that copper cooling stave should be used at the slag outlet to improve the cooling intensity and promote the precipitation of high-melting point substances, so as to slow down the erosion rate and improve the service life.