浅谈脱硫脱硝一体化

Integration of Desulfurization and Denitrification

"十二五"以来,我国环保部门对烟气排放指标要求越来越严格,国内为烟气脱销技术主要是SCR/SNCR工艺。SCR/SNCR工艺脱硝技术虽然比较成熟,但氨逃逸与烟气中的SO_3反应生成NH_4HSO_4,在250℃温度下粘符在尾部设备上,阻碍了锅炉热交换,降低了锅炉热效率。分析次氯酸钙脱销机理,理论上次氯酸钙脱硫脱销一体化向正方向进行。通过实验模拟:次氯酸钙脱硝可达到70%,脱硫效率可达到100%,脱硝效率可以与SNCR相媲美。脱硫脱硝一体化不仅能满足目前国家烟气运行排放要求,投资少,而且脱去烟气硫、硝时,对锅炉热效率没有任何影响,伴随其技术的不断成熟,湿法脱硫脱硝一体化未来将有美好的前景。

Since the 12th Five--Year Plan, Chinas environmental protection administration has issued more and more strict criteria on flue gas emission. The SCR/SNCR technology has been our primary denitrification method. Though this technology is relatively mature, the reaction of ammonia escape with SO3 in flue gas generates NH4HSO4, which will stick to the rear under the temperature of 2500C, and further impedes the boiler heat exchange and re- duces boiler thermal efficiency. Lab simulation shows that calcium hypochlorite can achieve 70% denitrification and 100% desulfurization, which compare favorably with the SNCR method. The method of integration of desulfuriza- tion and denitrification not only meets the national environmental demand, but also has less influence on boiler ther- mal efficiency with less investment. This integration of wet desulfurization and denitrification method needs to be further improved and will have a promising prospect in the future.