氯苯紫外光降解产物对生物过滤塔运行性能的影响

生物过滤技术对难生物降解VOCs的处理效果较差,构建紫外光降解-生物过滤联合处理工艺是解决难生物降解VOCs处理的一个有效手段.已有研究表明,紫外光降解预处理对氯苯生物过滤塔的去除性能有促进作用.为了考察紫外预处理对生物过滤塔的影响机理,本研究分别考察了氯苯紫外光降解主要产物氯酚、乙酸以及副产物臭氧对生物过滤塔运行性能的影响.研究结果表明,加入乙酸降低了生物过滤塔的氯苯去除性能,在增加喷淋量后去除性能有所恢复.加入邻氯酚使生物过滤塔的氯苯去除性能略有降低.臭氧明显促进了生物过滤塔的氯苯去除性能,当进口臭氧浓度在60～120mg.m-3时,氯苯平均去除率可由70%提高到90%以上.因此,臭氧是紫外预处理促进生物过滤塔运行性能的主要因素.

Effects of chlorobenzene photodegradation products on the performance of biofilters

A high-precision dual channel GC system was set up at Mt. Waliguan Global Atmosphere Watch Station, and used to measure atmospheric CH4, CO, N2O and SF6. The gases were identified by retention time on an Agilent 6890N gas chromatograph. The concentrations of CH4, CO, SF6 were calculated from peak height and N2O from peak area. The RSD (Relative Standard Deviation) of 110 repeated injections were better than 0.04% for CH4 (2000.3×10-9), 0.5% for CO (199.8×10-9), 0.08% for N2O (320.04×10-9) and 1.80% for SF6 (5.9×10-12). To meet the needs of high precision in|situ measurement, one standard gas injection was applied after every three unknown samples. Results from test operation showed that the system was suitable for background atmospheric CH4, CO and SF6 measurement with high precision, stability and reliability.