Abstract: To clarify the dominant factors affecting the service life of MgO-C bricks in different parts of the carbonization electric furnace,the corrosion status of the MgO lining was studied through lining erosion measurement,microstructure analysis,and phase composition analysis.The results show that:MgO-C bricks above the slag line undergo an oxidation reaction,leading to the detachment of MgO particles under thermal stress;after reacting with the slag,the products of MgO-C bricks at the slag line dissolve into the slag,and simultaneously,MgO particles continuously spall off under slag erosion,accelerating the corrosion rate;for MgO-C bricks near the furnace bottom,influenced by the insulating effect of the residual slag,the temperature gradient between heats is smaller,the thermal stress is relatively reduced,and the corrosion rate is slower than that at the slag line.

Key words: carbonization electric furnace, MgO-C brick, microstructure, corrosion mechanism, blast furnace slag

摘要： 为明确碳化电炉不同部位镁碳砖寿命衰减的主导因素,通过炉衬侵蚀量测量、显微结构和物相组成分析等手段,研究了碳化电炉不同部位镁碳质炉衬的侵蚀状况。结果表明:渣线上部镁碳砖因发生氧化反应,在热应力作用下导致MgO颗粒掉落;渣线部位镁碳砖与炉渣反应后,产物溶解于炉渣中,同时MgO颗粒在炉渣冲刷下不断剥落,使侵蚀速率加快;靠近炉底位置的镁碳砖,受剩余炉渣隔热作用影响,炉次间温度梯度较小,热应力相对降低,侵蚀速率较渣线位置的更慢。

关键词: 碳化电炉, 镁碳砖, 显微结构, 侵蚀机制, 高炉渣