Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
J Hazard Mater. 2017 Sep 15;338:186-193. doi: 10.1016/j.jhazmat.2017.05.037. Epub 2017 May 22.
Coking wastewater contains many types of toxic and hazardous pollutants that have serious toxic effects on human beings as well as aquatic organisms. However, few studies have evaluated the detoxification efficiencies of the treatment processes that are extensively performed in operational coking wastewater treatment plants (WWTPs). This study investigates the detoxification efficiencies of a combined anaerobic-anoxic-oxic (AO)-ozonation and AO-Fenton oxidation process in two coking WWTPs using an acute immobilization test for Daphnia magna, acute toxicity test for adult zebrafish, embryo toxicity test for zebrafish and the comet assay. The raw coking wastewaters displayed high acute daphnia and fish toxicity, zebrafish embryo toxicity and genotoxicity. The AO processing unit effectively removed acute and embryo toxicity, but not genotoxicity. In addition, the AO effluent quality did not meet the integrated wastewater discharge standard in China (GB18918-2002). The ozonation and Fenton oxidation units used as post-treatments in these two plants not only treated the coking wastewater to the discharge standard but also reduced the genotoxicity. However, the final effluents still showed potential genotoxicity after high dilution. The results suggest that the discharge of treated coking wastewater probably poses potential risks to human health and the environment even if it met regulatory standards.
焦化废水含有多种有毒有害物质，对人类和水生生物具有严重的毒性作用。然而，很少有研究评估在运行中的焦化废水处理厂（WWTP）中广泛进行的处理工艺的解毒效率。本研究采用大型溞急性固定化试验、成鱼急性毒性试验、斑马鱼胚胎毒性试验和彗星试验，研究了组合厌氧-缺氧-好氧（AO）-臭氧化和 AO-Fenton 氧化工艺在两个焦化 WWTP 中的解毒效率。原焦化废水表现出高急性大型溞和鱼类毒性、斑马鱼胚胎毒性和遗传毒性。AO 处理单元有效地去除了急性毒性和胚胎毒性，但不能去除遗传毒性。此外，AO 出水水质不符合中国综合废水排放标准（GB18918-2002）。这两个工厂中用作后处理的臭氧化和芬顿氧化单元不仅将焦化废水处理到排放标准，而且降低了遗传毒性。然而，即使经过高稀释，最终出水仍显示出潜在的遗传毒性。研究结果表明，即使处理后的焦化废水达到监管标准，也可能对人类健康和环境构成潜在风险。
