不同运行时间烟气脱硝催化剂性能对比分析

为研究运行时间对商用SCR烟气脱硝催化剂性能的影响,采用多种分析仪器对厦门某燃煤电厂SCR脱硝反应器中运行了10 080、25 145、30 288、40 368 h的催化剂（V2O5（WO3）/TiO2）进行试验与分析。试验结果表明：（1）SCR脱硝催化剂在运行30 000余小时后,SCR脱硝装置的脱硝效率低于60%,已不能满足燃煤电厂脱硝要求,需对催化剂进行更换或活性再生处理。（2）运行时间的增加会对催化剂孔道及内部介孔产生影响,从而间接影响脱硝效率。（3）随运行时间的延长,催化剂表面活性组分有一定的流失;催化剂表面水溶性离子和重金属元素均有增加的趋势。（4）4种催化剂试样表面未产生明显的活性组分与助催化剂二者的团聚,并且催化剂载体在运行了40 000余小时后仍保持锐钛矿晶型。

Comparative analysis of de-NO_x catalysts with different operation-time

The de-NOx catalysts with different operation-time were adopted.The comparative analysis on properties of the catalysts was made.The test and the analysis of SCR with different catalysts of 10 080,25 145,30 288 and 40 368 h were carried out.The results show that the last two ones,30 288(C3) and 40 368 h(C4),have unsatisfactory denitration rate which is lower than 60 % after 30 000 hours operation.Their performances cannot meet designed demand of the power plant.Moreover,the techniques of XRD,SEM,BET,FT-IR,IC and ICP-MS were used to characterize the objectives with different operation-time.The results indicate that the aggregations cannot be found remarkably,and the crystal form of carrier maintains the anatase style.However,the data from SEM show that the active compound on the surface of the catalyst runs off along with the operation-time,which is consistent with the analysis obtained from FT-IR.In the meantime,the channels and mesopores of catalysts are influenced badly with the long operation-time.Besides,there are also some water-soluble ions and trace heavy metals deposited on the surface of the catalysts.