多效助剂技术在降低FCC烟气污染物排放中的应用

Application of multi-functional additives technology for reducing FCC flue gas pollutant emissions

介绍了多效助剂技术在某公司两套催化裂化装置上的应用情况。针对两套催化裂化(FCC)装置在实际运行中存在省煤器段结盐(硫酸铵盐)严重、选择性催化还原(SCR)单元压力降升高快、烟气脱硫装置废水中氨氮含量升高、CO助燃剂加剂量大、稀相和密相温差大等问题,开展了多效助剂技术的研究及应用工作。应用结果表明:当多效助剂占催化剂系统藏量1.8%时,两套装置SCR进口烟气的NO x的质量浓度降低80%以上,SO x的质量浓度分别降低38.9%和65.4%,SCR单元的喷氨量和湿法烟气脱硫的碱耗量相应减少,SCR脱硝单元运行周期明显延长;助剂助燃效果良好,可以取代原有的CO助燃剂;助剂应用不会额外增加装置成本,还可以每天节省成本2100元以上;助剂应用期间,装置操作平稳,产品分布基本稳定。

It introduces the application of multi-functional additives in two catalytic cracking units of a company.Aiming at the problems of serious salt deposition(ammonium sulfate)in economizer section,rapid increase of SCR pressure drop,increase of ammonia nitrogen content in wastewater of flue gas desulfurization unit,high dosage of CO combustion promoter and large temperature difference between dilute phase and dense phase exist in the actual operation of two FCC units,the research and application of multi-effect additive technology have been carried out.The results show that when the additive accounts for 1.8%of the system catalyst reserves,the NO x content of the SCR inlet flue gas of the two sets is reduced by more than 80%,and the SO x content is reduced by 38.9%and 65.4%respectively.The ammonia injection volume of the SCR and the alkali consumption of wet flue gas desulfurization are correspondingly reduced,and the operating cycle of the SCR is significantly extended.The multi-functional additives has a good combustion effect and can replace the original CO combustion promotor,and it will not increase the cost of the unit and it can save 2100 yuan per day,the operation of the units is stable,and the product distribution are basically stable.