文献类型：期刊文献

英文题名：Removal and fate of polycyclic aromatic hydrocarbons in a hybrid anaerobic-anoxic-oxic process for highly toxic coke wastewater treatment

作者：Zhao, Wentao[1];Sui, Qian[2];Huang, Xia[3]

机构：[1]Tongji Univ, Coll Environm Sci & Engn, 1239 Si Ping Rd, Shanghai 200092, Peoples R China;[2]East China Univ Sci & Technol, Sch Resources & Environm Engn, State Environm Protect Key Lab Environm Risk Ass, Shanghai 200237, Peoples R China;[3]Tsinghua Univ, Dept Environm Sci & Engn, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100084, Peoples R China

年份：2018

卷号：635

起止页码：716

外文期刊名：SCIENCE OF THE TOTAL ENVIRONMENT

收录：;EI(收录号：20181705038496);WOS:【SCI-EXPANDED(收录号:WOS:000436494400069)】；

基金：This research was partly supported by the National Natural Science Foundation of China (51408425, 21577033, 21777042), Beijing Key Laboratory for Emerging Organic Contaminants Control, and the Fundamental Research Funds for the Central Universities. Analytical support by Dr. Xue Li of Tsinghua University is also greatly appreciated.

语种：英文

外文关键词：Highly toxic coke wastewater; Hybrid anaerobic-anoxic-oxic process; PAHs; Adsorption; Risk

摘要：Elimination of polycyclic aromatic hydrocarbons (PAHs) from coke wastewater is crucial to minimize the PAHs contamination levels to the environment. Knowledge about the characteristics of PAHs removal in biological treatment processes, especially hybrid systems, for real coke wastewater treatment has been very scarce. In this study, a lab-scale hybrid anaerobic-anoxic-oxic (A(1)/A(2)/O) process was used to treat highly toxic coke wastewater and operated more than 600 d at total hydraulic retention time (HRT) of 50 h, 40 h, 30 h, 20 h and internal mixed liquor recirculation ratio (R) of 3, 6, 9. Removal performance and behaviors of priority PAHs in the hybrid A(1)/A(2)/O system were investigated. The results showed that the appropriate total HRT and R from oxic reactor to anoxic reactor for organics and nitrogen removal was 40 h and 3, respectively. The concentrations of total PAHs were very high (254-488 mu g/L) in the raw coke wastewater, and effectively reduced to 4.1-4.5 mu g/L in the final effluent by the present system under the optimized operational conditions. Among the three treatment units, anoxic reactor made the largest contribution to the total PAHs removal. Large amounts of PAHs (415-1310 mu g/g) were adsorbed to the activated sludge in the anoxic and oxic reactor, leading to a much higher load of PAHs (2535 mu g/d) in the excess sludge than that in the treated coke wastewater (93 mu g/d) at SRT 60 d. Therefore, the excess sludge was identified as the major emission source of PAHs in coke wastewater during the hybrid A(1)/A(2)/O process, and might pose an environmental risk if the excess sludge was not properly treated and disposed. (C) 2018 Elsevier B.V. All rights reserved.