生物滴滤降解氯苯废气的实验研究

采用定向驯化活性污泥接种生物滴滤塔（BTF）处理氯苯废气,考察BTF稳定运行阶段的运行性能、微生物平均代谢活性（AWCD）及微生物种群结构.结果表明,当进口浓度低于0.6 g·m-3时,EBRT高于45 s时,BTF对氯苯总去除率维持在80%以上,因此,BTF在处理中低浓度（≤0.6 g·m-3）氯苯废气具有较明显的优势;当进气负荷〉80 g·（m3·h）-1时,去除负荷趋于稳定,为70 g·（m3·h）-1左右;CO2的生成量与氯苯的去除负荷的比值为1.92,表明BTF对氯苯较高程度的矿化（考虑部分有机碳用于微生物自身的生长）;BTF对氯苯的降解行为符合Michaelis-Menten动力学模型,单位体积最大降解速率rmax为35.6g·（m3·h）-1·AWCD值分析表明塔内微生物具有较高的生物活性.生物膜PCR-DGGE指纹图分析表明,在稳定运行阶段塔内微生物种群结构具有较高程度的稳定性和复杂性,而微生物种群的稳定性和复杂性同时也促进BTF对目标污染物的高效降解和矿化.

BTF Performance Treating a Chlorobenzene-Contaminated Gas Stream

In this study, biotrickling filter (BTF) inoculated with acclimated sludge was established to treat waste gas containing chlorobenzene. The BTF performance, average well color development (AWCD) values and microbial community were examined in steady state. Results revealed BTF achieved removal efficiency more than 80% of chlorobenzene under the conditions of < 0.6 g x m(-3) inlet concentration and > 45 s EBRT. Therefore, BTF have an advantage in treating low-concentration waste gas containing chlorobenzene (< or = 0.6 g x m(-3)). The overall chlorobenzene elimination capacity reached a maximum of 70 g x (m3 x h)(-1) at an inlet load of 80 g x (m3 x h)(-1). The mass ratio of carbon dioxide produced to the BTo-X removed was approximately 1.92, which confirms complete degradation of chlorobenzene, given that some of the organic carbon consumed is also used for the microbial growth. The degradation of chlorobenzene in the BTF followed Michaelis-Menten kinetic model, the maximum specific degradation rate (r(max)) was 35.6 g x (m3 x h)(-1). The AWCD values indicated that the microorganisms in the BTF showed high the microbial metabolic activity. The PCR-DGGE fingerprinting analysis on biofilm samples in the BTF indicated that the microbial community had a relative stability and complexity during the steady-state phase. The stability and complexity of microbial community could contribute to the degradation and mineralization of chlorobenzene in BTF.