对废弃脱硝催化剂处理后重新加工再生,研究了添加剂对其粉体成型和再生催化剂脱硝活性的影响,探讨了反应温度、空速、n(NH3)∶n(NO)摩尔比、氧含量、H2O和SO2对再生催化剂NH3选择性催化还原(SCR)NO的影响。结果表明:最佳再生条件是使用5%羧甲基纤维素和10%无机粘结剂辅助成型;废弃催化剂再生利用率高达90%;再生催化剂抗压强度为4.73 MPa,优于商用催化剂;空速5 000 h-1、氨氮摩尔比1、氧含量6%时,脱硝活性温度窗口为310~450℃,350℃时活性最高为94%;350℃时,单独通入1 000×10-6SO2或10%H2O对再生催化剂活性均有一定抑制作用,最低活性分别为70%和81%,停止通入SO2或H2O后其活性逐渐恢复;同时通入1 000×10-6SO2和10%H2O,再生催化剂活性下降至63%并于1 h内保持相对稳定,停止通入SO2和H2O 2 h后,活性逐渐恢复到73%。
The waste denitrification catalyst was regenerated by processing after soot blowing.Effects of additives on catalyst molding and catalytic activity of the regenerated catalyst for denitrification were separately studied.The influences of reaction temperature,the space velocity,NH 3 / NO mole ratio,the oxygen concentration,H2O and SO2 on the NO conversion of the regenerated catalyst for selective catalytic reduction(SCR) of NO with ammonia were evaluated.The results showed that adding 5% carboxymethyl cellulose and 10% inorganic binder for molding was the best regeneration methods;the utilization rate of the waste catalyst could reach to 90%.The compressive strength of the regenerated catalyst reached 4.73MPa,which was better than that of the commercial catalyst.Moreover,when the n(NH3) ∶ n(NO) was equal to one,the space velocity was 5 000 h-1,and the oxygen concentration was 6 %,its active temperature window was 310 ~ 450 ℃ and the highest activity could reach 94% at 350 ℃.The catalytic activities of the regenerated catalyst were inhibited in the presence of 1 000 × 10-6 SO2 or 10 % H2O,and the catalytic activities still maintained 70% and 81% respectively at 350℃.However,the catalytic activity decreased greatly in presence of 1 000 × 10-6SO2 and 10% H2O,and the catalytic activity obviously decreased to 63% but remained stable within 1h,the catalytic activity was able to recover 73% in 2 h after removing the SO2 and H2O.