摘要
制备了具有工业应用价值的V2O5/TiO2负载WO3与MoO3的蜂窝状SCR催化剂,并在某燃煤电厂烟气环境下,对其催化性能进行了测试,结果表明:增大催化剂体积能够提高脱硝效率,但活性增量逐步下降,当脱硝效率达到80%以上时,继续增大催化剂体积其活性提高不显著。催化剂的脱硝活性随着积灰时间的延长而降低,脱硝系统运行4h后,催化剂脱硝活性减少9.4%。在燃煤电厂尾气飞灰浓度约为0.031kg.m-3环境下,为满足尾气中NOx浓度排放要求(<200mg·m-3),每连续运行6h需进行一次吹灰。催化剂的脱硝性能随着运行时间的延长,先急剧下降,后缓慢降低。在连续运行48～168h范围内,脱硝活性下降值小于1%,SO2氧化率下降值小于0.1%。在12个月内,平均每连续运行700h,脱硝活性降低1%。
A honeycomb SCR catalyst of V2O5/TiO2 with WO3 and MoO3 was prepared and its deNOx performance was investigated in a pilot plant test using flue gas of a coal-fired power plant.The results show that the larger catalyst volume is,the higher deNOx efficiency,and SO2 oxidation increases too,but increase ratio becomes smaller.When deNOx efficiency is above 80%,the outlet NOx concentration met the emission standards,and the efficiency improvement is not significant by further enlarging catalyst volume which led to higher construct cost.In order to obtain the best ratio of deNOx efficiency to catalyst volume and avoid resources waste for single requirement of higher deNOx efficiency,SCR catalyst volume should be adjusted for different boiler types,according to flue gas component of coal-fired power plant and national emission standards.The deNOx efficiency reduces with soot increase deposited,and drops about 9.4% within 4 h of soot depositing.The outlet NOx concentration can be at 198 mg·m-3 after 8 h of soot depositing.At 0.031 kg·m-3 of fly ash concentration,the soot deposited needed to be blown each 6 h to obtain a satisfied deNOx efficiency（80%）.When run time prolongs,the deNOx efficiency falls sharply first,and then reaches a relative stable level.Within 48—168 h,the deNOx efficiency and SO2 oxidation decline less than 1% and 0.1%,respectively.After continuous run for 3 months（2160 h）,the NOx concentration at outlet of SCR tower is 196 mg·m-3.The deNOx efficiency declines at a rate of 1% per 700 h for continuous 12 month run.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2013年第7期2611-2618,共8页
CIESC Journal
基金
山东省科技发展计划项目(2011GSF11716)~~
