摘要
鉴于生物法对难生物降解性、低水溶性的VOCs去除效果不佳,因此开发高效的前处理技术来提高生物法的净化能力已成为新的热点.本实验以生物可降解性差的氯苯为目标污染物,以介质阻挡放电低温等离子体(DBD)为生物法的前处理技术,通过调节DBD反应器的工艺参数,研究其对氯苯的降解效果,考察了进气浓度、停留时间、湿度、峰值电压等因素对去除率的影响,并对尾气进行初步分析.结果表明,DBD能有效去除氯苯废气,氯苯去除率随峰值电压的升高而增大;当电压≥12k V时,停留时间对氯苯的降解影响较小;65%~75%为氯苯降解的最佳湿度范围.通过产物分析,发现产物的种类和浓度随着放电电压的升高而增多增大,主要是以有机酸类和氯代烃为主.产物的水溶性较好;可生化性随着电压升高而增强;随电压升高,小球藻受到的生长抑制作用越来越小,当电压达到20k V时,反而有促进作用.降解过程中产生的O3量随着电压的升高而增多,并且在同一电压下臭氧产生量随着湿度的增大而增多.
For non-biodegradable volatile organic compounds( VOCs) with low water solubility,the tradition biological method can not achieve a satisfactory removal efficiency,so development of high efficiency pre-treatment technology is a hot issue of research. In this experiment,using poor biodegradable chlorobenzene as the target pollutant and dielectric barrier discharge( DBD) non-thermal plasma as the pretreatment technology for biotrickling filter( BTF),the effect of DBD on the degradation of chlorobenzene was studied by adjusting the technical parameters of DBD. The effects of the inlet concentration,residence time,humidity and peak voltage on decomposition efficiency were investigated and the decomposition products of chlorobenzene were analyzed. Experimental results showed that DBD could effectively remove waste gaseous chlorobenzene,the removal rate of chlorobenzene increased with the increasing peak voltage. When the peak voltage was ≥12k V,less effect of residence time on the degradation of chlorobenzene was found. The optimal humidity range of degradation chlorobenzene was 65%- 75%. Through the analysis of degradation products, the species and concentrations of degradation products increased with the increase of discharge voltage. The products were mainly consisted of organic acids and chlorinated hydrocarbons. The water solubility of degradation products was preferable. Furthermore,with the increase of discharge voltage,the biodegradability of degradation products became higher and higher and the biological toxicity was reduced. It had a promoting effect on the degradation of chlorobenzene when the voltage reached 20 k V. Meanwhile,the O3 concentration increased with the increasing discharge voltage and also enhanced with the rising humidity under the same voltage.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2015年第3期831-838,共8页
Environmental Science
基金
浙江省科技厅国际科技合作专项项目(2013C24003)
浙江省自然科学基金项目(LY14E080009)
国际科技合作项目(2011DFA92660)
关键词
介质阻挡放电
氯苯
降解特性
产物分析
dielectric barrier discharge
chlorobenzene
characteristics of degradation
product analysis
