焦化废水A^2/O处理过程中的组成和毒性变化规律  

Compositional and Toxic Variations of Coking Wastewater in an A^2/O Treatment Process

作　　者：刘聪[1] 陈吕军[1,2] 朱小彪[1] 马德华[1] 

机构地区：[1]清华大学环境学院,北京100084 [2]浙江省水质科学与技术重点实验室,浙江清华长三角研究院,嘉兴314006

出　　处：《生态毒理学报》2014年第2期291-298,共8页Asian Journal of Ecotoxicology

基　　金：国家自然科学基金(51308319)

摘　　要：焦化废水中含有大量毒性物质,具有较强的生物毒性。本文以实验室构建的A2/O焦化废水处理系统为研究对象,考察废水处理过程化学成分和急性毒性的变化。采用紫外扫描和三维荧光光谱分析考察了处理系统各阶段出水的物质组分,并采用固相萃取和超滤膜分离等手段对水样各组分的发光细菌急性毒性进行研究。结果表明,伴随着芳香族物质等毒物的去除,焦化废水的急性生物毒性在该处理系统中被逐步削减,最终出水的毒性当量仅为原水的28%;不同组分的生物毒性测试结果显示,废水水样的强极性和中等极性有机组分贡献了绝大部分的毒性当量,而这些物质主要在缺氧段及好氧段被削减;结合三维荧光光谱的分析结果,可推断焦化废水中一类很难在A2/O处理系统中被完全去除的芳香族蛋白质类似物(Ⅱ区)很可能具有较强的生物毒性,是构成出水毒性的主要物质。Coking wastewater contains abundant toxic substances and has significant biological toxicity. In thepresent study, chemical compositions and acute toxicities were assessed simultaneously in a simulated A2/Otreatment process for coking wastewater. Luminescent inhibition test was employed to evaluate variations of a-cute toxic potential, and chemical compositions were measured by UV spectrometry and three dimension fluores-cence spectrometry （TDFS）. A fractionation-based bioassay was also applied to the effluents of different treat-ment processes, where samples were fractionated by solid-phase extraction （SPE） and ultrafdter membrane sepa-ration before ultraviolet scanning and fluorescence spectroscopy were applied to characterize the main compo-nents. The results showed that the acute toxicities of effluents had been reduced gradually in the studied A2/Osystem, and the toxic unit of final effluent was 28% of that of raw wastewater, accompanied by removal of aro-matic chemicals from the wastewater. Based on the TDFS, it showed that aromatic protein-like substances （re- gion II） might be highly toxic component in the treated water, which could be hardly eliminated by A2/O process. According to the results of the fractionation-based bioassay, the polar and mid-polar components in wastewater samples contributed to most of the toxicity, which could be mostly reduced by anoxic and MBR re- actors.

关 键 词：焦化废水 A2 O工艺 急性毒性 组成变化 因果关系分析 

分 类 号：X171.5[环境科学与工程—环境科学]