生物滴滤塔处理低浓度氮氧化物

Removal of nitrogen oxides of low concentrations in biofilter packed with activated carbon

采用活性炭填料挂膜的生物滴滤塔净化低浓度氮氧化物废气,研究结果表明,生物净化效率可达99%。适宜的喷淋量为3L/h,适宜的气体流量为0.4～0.5m3/h。当气体流量在0.56m3/h,入口气体氮氧化物浓度为480mg/m3,停留时间18.4s时,氮氧化物的净化效率可达到96.67%。净化氮氧化物的反硝化菌大部分为副球菌属(Paracoccus)中的细菌,也有小部分硫杆菌属(Thiobacillus)中的细菌。活性炭生物净化氮氧化物废气主要发生在活性炭外表面,而活性炭内表面发生的生化反应很少。

A biofilter packed with activated carbon was set up to study the removal of nitrogen oxides of low concentration under high flow load. The experimental result showed that the best NOx purifying efficiency reached 99%. The optimum sprinkling amount and gas flow were 3L/h and 0.4-0.5m^3/h, respectively. When gas flow was 0.56m^3/h, NOx concentration in inlet gas was 480 mg/m^3 and residence time was 18.4s, the purification efficiency of NOx could reach 96.67%. The main denitrifying bacteria were Paracoccus and Thiobacillus; the biological purification reaction took place mainly not on internal surface but on external surface of activated carbon attached with biofilm.