钒钛基SCR脱硝催化剂失活原因分析  

Deactivation of vanadium and titanium based SCR catalyst used in coal-fired power plants

作　　者：盘思伟[1] 程华[2] 韦正乐[1] 黄碧纯[2,3] 阮东亮[2] 

机构地区：[1]广东电网公司电力科学研究院,广东广州510080 [2]华南理工大学环境科学与工程学院,广东广州510006 [3]华南理工大学环境科学与工程学院,广东广州510006 [4]广东省大气环境与污染控制重点实验室广东广州510006

出　　处：《热力发电》2014年第1期90-95,共6页Thermal Power Generation

摘　　要：针对某燃煤电厂钒钛基选择性催化还原(SCR)脱硝催化剂失活现象,运用N2吸附-脱附、扫描电子显微镜(SEM)、X射线衍射(XRD)、X射线荧光(XRF)、热重分析(TGA)、傅里叶变换红外光谱(FT-IR)、程序升温还原(H2-TPR)分别对新鲜催化剂和已运行30 000h的旧催化剂进行结构表征,并结合SCR脱硝模拟试验考察K、Na、Ca、As等元素对催化剂活性的影响,综合分析SCR脱硝催化剂的失活原因。分析结果表明,催化剂活性降低是多种因素共同作用的结果,其中活性组分流失、碱/碱土金属和砷中毒是导致催化剂活性降低的主要原因,毒性组分中又以As影响最大,Ca、Na次之,K含量的增加在一定程度上造成了催化剂的失活,但影响有限。Taking the vanadium and titanium based SCR catalysts applied in a coal-fired power plant as research objects, fresh catalyst and after 30 000 hours＇ operation catalyst were structural characterized by several analysis, such as N2 adsorption-desorption, SEM, XRD, XRF, TGA, Fou- rier-transform infrared （FT-IR） spectroscopy and temperature programmed reduction （H2- TPR）. Furthermore, combing with the SCR denitration simulation test, the effect of K, Na, Ca, As and other elements on activation of the catalyst was investigated to find out the reason for deacti- vation of the SCR denitration catalyst comprehensively. The results show that, decrease in catalyst activation was a combination action caused by multiple factors, among which the active component loss and being poisoned by alkali/alkaline earth metal and As were the major reasons. In all toxic components, As had the greatest effect on the catalyst＇s deactivation, then was Ca and Na. The in- crease of K also reduced the catalyst＇s activity to some extent,but with a limitation.

关 键 词：烟气脱硝 选择性催化还原 催化剂失活 中毒 碱金属 砷 

分 类 号：TQ426.83[化学工程]