关于高炉炉缸长寿的关键问题解析

 高炉长寿化是大型高炉发展的必然趋势,实现高炉长寿的关键在于弄清高炉侵蚀的根本原因。从高炉炉缸侵蚀机理、高炉炉缸象脚型侵蚀原因、高炉炉缸圆周方向侵蚀不均匀性、高炉冷却强度与冷却效率以及高炉炉缸维护技术等5个方面探讨了高炉长寿存在的共性问题,指出高炉炉缸炭砖损毁的本质是碳不饱和铁水对炭砖的溶蚀。具体结果表明,首先,高炉炉缸象脚型侵蚀最严重部位位于高炉炉缸死料柱的根部位置;其次,阐明了直接导致高炉存在不均匀侵蚀的主要原因在于冷却系统的冷却水量和送风系统的风量在高炉周向方向分配不均匀;然后,阐明了冷却系统的作用本质是降低耐火材料热面温度,并提出了高炉冷却强度指数及高炉冷却效率指数;最后,分析了采用无钛矿护炉和钛矿护炉两种模式的高炉炉缸维护技术。

Analysis of key issues on longevity of blast furnace hearth

Longevity of blast fornace is an inevitable trend of developing of large blast furnace. The key lies in the long life of a blast furnace is to find out the basic reason for blast furnace corrosion. Aiming at the issue, the common problems of blast furnace longevity from five aspects were discussed: The essence of blast furnace hearth erosion, the mechanism of "elephant-like erosion" in blast furnace hearth, the inhomogeneity of erosion in the circumferential direction of blast furnace hearth, the analysis of blast furnace cooling intensity and efficiency, and the maintenance technology of blast furnace. As a result, it was pointed out that the nature of carbon brick damage in the blast furnace hearth is the corrosion of carbon brick by carbon-unsaturated hot metal. The details are as follows: Firstly, the most serious part of "elephant-like erosion" was located at the root of dead stock columns. Secondly, it clarified that the main reason for the inhomogeneity of erosion was the uneven distribution of cooling water and air volume of blast system in the circumferential direction of blast furnace. Thirdly, the actual function of the cooling system was illustrated, which was to lower the hot surface temperature of refractory. Additionally, the cooling strength index and cooling efficiency index of blast furnace were proposed. At last, the maintenance technology of blast furnace hearth was explored by using two modes: titanite-free furnace protection and titanite furnace protection.