Xi Jinying, Saingam Prakit, Gu Feng, Hu Hong-Ying, Zhao Xuefei
Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, 100084, Beijing, People's Republic of China,
Appl Microbiol Biotechnol. 2015 Jan;99(1):33-42. doi: 10.1007/s00253-014-6248-8. Epub 2014 Dec 11.
Biofilters treating high-concentration gaseous volatile organic compounds (VOC) can be subject to bed clogging induced by excess biomass accumulation. In this study, O3 was continuously injected into biofilters to control biomass. Its effects on the performance of the biofilters and on biomass accumulation were investigated. Four identical biofilters designed to treat gaseous toluene were operated for 70 days, and three of them were continuously injected with O3 at different concentrations (from 80 to 320 mg/m(3)). The results showed that continuous O3 injection could effectively keep the bed pressure drop stable and had no adverse effect on toluene removal when O3 concentrations were 180-220 mg/m(3). The maximum toluene elimination capacity of the four biofilters was 140 g-toluene/m(3)/h, and the bed pressure drop of the biofilter fed with 180-220 mg/m(3) O3 remained below 3 mmH2O/m throughout the operation period. The biomass accumulation rates of the three biofilters with O3 at 80-320 mg/m(3) were lowered by 0.15-0.25 g/L/day compared with the biofilter without O3. The decreases in biomass accumulation resulted in higher void fractions of the filter beds with O3 injection. Carbon balance analysis indicated that CO2 production had increased while biomass accumulation and leachate waste production decreased in response to O3 injection. Based on the experimental results, it was concluded here that continuous O3 injection can reduce increases in bed pressure effectively, preserve VOC removal capacity, and prevent production of extra leachate waste.
处理高浓度气态挥发性有机化合物(VOC)的生物滤池可能会因过量生物质积累而导致滤床堵塞。在本研究中,向生物滤池中连续注入臭氧(O₃)以控制生物质。研究了其对生物滤池性能和生物质积累的影响。设计了四个相同的用于处理气态甲苯的生物滤池,运行70天,其中三个滤池以不同浓度(80至320毫克/立方米)连续注入O₃。结果表明,当O₃浓度为180 - 220毫克/立方米时,连续注入O₃可有效保持滤床压降稳定,且对甲苯去除无不利影响。四个生物滤池的最大甲苯去除能力为140克甲苯/立方米/小时,注入180 - 220毫克/立方米O₃的生物滤池在整个运行期间滤床压降保持在3毫米水柱/米以下。与未注入O₃的生物滤池相比,注入80 - 320毫克/立方米O₃的三个生物滤池的生物质积累速率降低了0.15 - 0.25克/升/天。生物质积累的减少导致注入O₃的滤床孔隙率更高。碳平衡分析表明,注入O₃后,二氧化碳产量增加,而生物质积累和渗滤液废物产量减少。基于实验结果,得出结论:连续注入O₃可有效降低滤床压力增加,保持VOC去除能力,并防止产生额外的渗滤液废物。