冷轧退火炉烟气脱硝轻量化技术

Lightweight denitration technology of flue gas for annealing furnace

针对冷轧退火炉半封闭式烟气排放系统因冷风吸入量大而导致脱硝成本高的问题,进行烟气脱硝轻量化技术研究。通过建立烟气排放量计算模型,得到燃烧过程和排放过程中的冷风吸入是退火炉烟气排放量增加的主要原因;通过设计“山”形柔性连接装置,在解决烟气排放过程中冷风吸入问题的同时,实现了设备改造不停机作业。烟气脱硝轻量化技术应用后,国内某机组退火炉南区和北区的NOx排放浓度降幅分别为37.36%、41.81%,烟气排放量降幅分别为59.34%、65.25%,烟气温度增幅分别为67.77%、117.51%。除减少脱硝设备一次性投资费用和不停机改造所带的效益共计1524.31万元外,每年可实现经济效益571.27万元。

Aiming at the problem of high denitrification cost due to the large amount of cold air inhalation in the semi-closed flue gas emission system of traditional annealing furnace,the research on lightweight denitrification technology of flue gas was carried out.Through the establishment of flue gas emission calculation model,the main reasons for the increase in flue gas emissions from annealing furnace are the inhalation of cold air during the combustion process and the emission process.Through the design of the"mountain"-shaped flexible connecting device,it realizes the equipment modification without stopping the operation while solving the problem of inhalation of cold air in the process of flue gas emission.After the application of lightweight denitrification technology of flue gas in a domestic annealing furnace,NOx emission concentration of the hood annealing unit in the south and north zones decreased by 37.36%and 41.81%respectively,the flue gas emission decreased by 59.34%and 65.25%respectively,and the flue gas temperature increased by 67.77%and 117.51%respectively.In addition to reducing the one-time investment cost of denitrification equipment and the benefits brought by the non-stop renovation totaling RMB 15.2431 million,the annual economic benefits can be realized to RMB 5.7127 million.