催化裂化装置非氨生物基还原脱硝技术工业试验总结

Summary of industrial application of non-ammonia bio-based denitrification technology in FCC unit

针对催化裂化装置实际生产中选择性催化还原技术(SCR)脱硝存在运行成本高、床层有压力降、SO_(2)氧化导致烟气蓝烟拖尾严重及后续脱硝技术路线如何选择的问题,开展了非氨生物基还原脱硝技术的工业试验并进行了技术分析。结果表明:非氨脱硝还原技术用于不完全再生催化裂化装置CO余热锅炉,在喷雾覆盖面积仅占烟气流通总截面积30%~40%的有限条件下,可将烟气中NO_(x)质量浓度由130.6 mg/m^(3)降至44.8 mg/m^(3),NO_(x)平均脱除率为65.8%,满足烟气NO_(x)环保排放指标要求,同时可避免烟气中SO_(2)氧化成SO_(3),减少烟气中蓝色烟羽的生成,对外排含盐污水COD(化学需氧量)、NH_(3)^(-)N等指标以及CO余热锅炉的平稳运行无影响;对新建装置而言,采用非氨脱硝还原技术替代SCR技术,可降低设备投资和操作成本。

In the actual production of the FCC unit,the selective catalytic reduction(SCR)denitration has the problems of high operating costs,pressure drop in the bed,serious blue tailing caused by SO_(2) oxidation,and how to choose the subsequent denitration technology routes.Therefore,industrial trial of non-ammonia bio-based denitrification technology is carried out and technical analysis is conducted.The application results show that when the non-ammonia bio-based denitrification technology is used for CO boiler of the incomplete regeneration FCC unit,under the condition that the spray coverage area only accounts for 30%~40%of the total flue gas flow area,the NO_(x) mass concentration in flue gas can be reduced from 130.6 mg/m^(3) to 44.8 mg/m^(3),and the denitration rate is 65.8%,which meets the requirements of the flue gas NO_(x) environmental protection emission index,while avoiding the oxidation of SO_(2) in the flue gas to generate SO_(3),and reducing the generation of blue tailing,and having no adverse effects on the COD,NH_(3)^(-)N and other indicators of discharged saline waste water,as well as the smooth operation of CO boiler.For new installations,non-ammonia bio-based denitrification technology can replace SCR technology,reducing equipment investment and operating costs.