Environmental Simulation and Pollution Control State Key Joint Laboratory, Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, PR China.
Environ Sci Technol. 2009 Dec 15;43(24):9407-12. doi: 10.1021/es9019035.
Recalcitrant volatile organic compounds with low biodegradabilities pose challenges for biofiltration technologies. In this study, the effects and mechanism of adding ozone on the performance of a biofilter were investigated. A biofilter treating chlorobenzene was set up and operated continuously for 265 days under different inlet ozone concentrations. Results showed that ozone below 120 mg m(-3) could notably enhance the biofilter performance. The average chlorobenzene removal efficiency increased from 40 to 70% and then to 90% while the inlet ozone concentration rose from 0 to 40 mg m(-3) and 120 mg m(-3). Reducing ozone concentration resulted in a decrease in removal efficiency from 90 to 40%. Further analysis indicated that the thickness and extra-cellular polymer substance content of the biofilm were remarkably reduced while inlet ozone concentration was gradually increased. Meanwhile, the specific surface areas of the filter bed were found to increase from 784 to 820 and 880 m(2) m(-3). A respiratory quinone profile showed that the dominant quinone shifted from ubiquinone-8 to menaquinone-9(H(2)) after ozone was added. This indicated that some Gram-positive bacteria with thick cell wall became the dominant species under ozone compression.
对于生物过滤技术来说，具有低生物降解性的顽固挥发性有机化合物是一个挑战。在这项研究中，考察了添加臭氧对生物滤池性能的影响和机制。建立了一个处理氯苯的生物滤池，在不同的入口臭氧浓度下连续运行 265 天。结果表明，低于 120mg/m(3)的臭氧可以显著提高生物滤池的性能。当入口臭氧浓度从 0 增加到 40mg/m(3)和 120mg/m(3)时，氯苯的平均去除效率从 40%提高到 70%，然后提高到 90%。降低臭氧浓度会使去除效率从 90%降低到 40%。进一步的分析表明，随着入口臭氧浓度的逐渐增加，生物膜的厚度和胞外聚合物物质的含量明显减少。同时，发现滤床的比表面积从 784m(2)/m(3)增加到 820m(2)/m(3)和 880m(2)/m(3)。呼吸醌图谱表明，加入臭氧后，优势醌从泛醌-8转移到了甲基萘醌-9（H(2)）。这表明，一些具有厚细胞壁的革兰氏阳性菌在臭氧压缩下成为优势种。
