| In recent years, haze issue has caused universal attention. The problem of environental pollution treatment is urgent. The selective catalytic reduction (SCR) is an effective way to remove NOx from flue gases. According to the actual situation of China, the low-temperature SCR technology has broad application prospects. The bag-type dust removal technology is one of commonly used of dust removal technology. Eliminating multiple contaminants simultaneously can save space and investments, and it is also the development direction of pollution control in the future. Therefore, the research about the coupling of SCR of NOx and dust removal on a catalytic fabric dust filter has important significance.In the paper,the catalyst with double function was prepared by methods of in-situ reaction and adhesive coating load, respectively. The NO conversion and the mechanical property of the catalyst prepared by the two methods were analyzed, then the best method is selected. The catalyst were characterized by XRD, BET, XPS, FESEM and so on. And the influences of reaction temperature, Mn loading, oxygen content, water vapour and SO2 to the de-NO activity of the catalyst were also studied. The results show NO conversion of the catalyst prepared by the two methods is very close (GHSV=6000h-1, NH3/NO=1:1, O2 3%,160℃-19℃, NO conversion 85%-90%), but degree of injury of PPS fibers and the solid degree of the active component of the catalyst prepared by method of adhesive coating load is better than that by method of in-situ reaction. The influences of water vapour to de-NO activity of catalyst can be restored, but the influences of SO2 can’t be recovered.The property of SO2 resistance and NO conversion of the catalyst is optimized by the methods of doping elements M(M= Ce, Fe, Co, Ni, La, Sn) and the change of gas com-position. The results showed the method of doping elements can only delay the speed of catalyst sulphate poisoning. However, the reaction competitiveness of NO2 with NH3 stro-nger than SO2 with NH3, which can thoroughly solve the problem of sulphate poisoning. The results showed that NO conversion of MnOx reached 85% at 250℃ after 4 h with GHSV= 21000h-1, SO2=200ppm, NO2=200ppm, NO=400ppm, NH3/N2= 1:1 and 3% O2. |
