紫外光降解高浓度氯苯气体的研究

为评价紫外光降解作为高浓度挥发性有机物生物预处理的可行性，系统考察了其对高浓度氯苯气体的去除性能及其影响因素.所考察的影响因素包括紫外光波长、进口ρ(氯苯)、空塔停留时间和气体相对湿度等.结果表明:复合254和185 nm波长紫外光照射对氯苯的去除效果优于单一254 nm波长；紫外光降解反应器的进口ρ(氯苯)在2 300～2600 mg/m3，空塔停留时间为27 s时，对氯苯气体的去除率可达40%,继续延长空塔停留时间对氯苯去除率的提高作用有限；进口ρ(氯苯)在150～3 000 mg/m3时，氯苯去除速率随进口浓度单调增加，当高于3 000 mg/m3时，氯苯去除速率基本保持不变；增加气体相对湿度可以提高紫外光降解反应器对氯苯的去除效果. 

Photo-Degradation of High Concentration of Chlorobenzene in Gas Phase by Ultraviolet Radiation

High concentration gaseous chlorobenzene was treated using ultraviolet(UV) radiation to evaluate the feasibility of UV technology as a pretreatment for biological removal of high concentration of halogenated volatile organics. The factors affecting the performance of the UV reactor, including UV wavelength, inlet mass concentration of chlorobenzene, empty bed retention time (EBRT) and relative humidity, were examined. The results indicated that single wavelength of254 nm showed no apparent removal of chlorobenzene while combination of 254 nm and 185 nm could demonstrate a good elimination capacity of chlorobenzene. Underthe condition of inlet mass concentration of 2 300～2 600 mg/m3 and EBRT of 27 s, about 40% of chlorobenzene was removed. Further increase of EBRT had little improvement in removal efficiency. Within the inlet mass concentration of more than 3　000 mg/m3, the chlorobenzene removal rate was less dependent on concentration, while showed an increasing relationship with the inlet mass concentration between the range of 150～3 000 mg/m3. Furthermore, the increase of relative humidity could enhance both removal efficiency and removal rate of chlorobenzene. The resultsdemonstrated a competitive potential as a pretreatment for high concentration of volatile organic compounds.