Dehua Ma, Cong Liu, Xiaobiao Zhu, Rui Liu, Lujun Chen
Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
School of Environment, Tsinghua University, Beijing, 100084, China.
Environ Sci Pollut Res Int. 2016 Sep;23(18):18343-52. doi: 10.1007/s11356-016-6882-z. Epub 2016 Jun 9.
This study investigated the changes of toxic compounds in coking wastewater with biological treatment (anaerobic reactor, anoxic reactor and aerobic-membrane bioreactor, A1/A2/O-MBR) and advanced physicochemical treatment (Fenton oxidation and activated carbon adsorption) stages. As the biological treatment stages preceding, the inhibition effect of coking wastewater on the luminescence of Vibrio qinghaiensis sp. Nov. Q67 decreased. Toxic units (TU) of coking wastewater were removed by A1/A2/O-MBR treatment process, however approximately 30 % TU remained in the biologically treated effluent. There is a tendency that fewer and fewer residual organic compounds could exert equal acute toxicity during the biological treatment stages. Activated carbon adsorption further removed toxic pollutants of biologically treated effluent but the Fenton effluent increased acute toxicity. The composition of coking wastewater during the treatment was evaluated using the three-dimensional fluorescence spectra, gas chromatography-mass spectrometry (GC-MS). The organic compounds with high polarity were the main cause of acute toxicity in the coking wastewater. Aromatic protein-like matters in the coking wastewater with low biodegradability and high toxicity contributed mostly to the remaining acute toxicity of the biologically treated effluents. Chlorine generated from the oxidation process was responsible for the acute toxicity increase after Fenton oxidation. Therefore, the incorporation of appropriate advanced physicochemical treatment process, e.g., activated carbon adsorption, should be implemented following biological treatment processes to meet the stricter discharge standards and be safer to the environment.
本研究调查了焦化废水在生物处理阶段（厌氧反应器、缺氧反应器和好氧膜生物反应器，A1/A2/O-MBR）以及深度物理化学处理阶段（芬顿氧化和活性炭吸附）中有毒化合物的变化情况。随着生物处理阶段的推进，焦化废水对青海弧菌Q67发光的抑制作用减弱。A1/A2/O-MBR处理工艺去除了焦化废水的毒性单位（TU），然而，经生物处理后的出水仍残留约30%的TU。在生物处理阶段，残留有机化合物产生同等急性毒性的趋势越来越小。活性炭吸附进一步去除了经生物处理后出水中的有毒污染物，但芬顿氧化后的出水急性毒性增加。利用三维荧光光谱、气相色谱-质谱联用仪（GC-MS）对焦化废水处理过程中的成分进行了评估。高极性有机化合物是焦化废水急性毒性的主要原因。焦化废水中难生物降解且毒性高的类芳香族蛋白质物质是经生物处理后出水剩余急性毒性的主要贡献者。芬顿氧化后氧化过程产生的氯导致急性毒性增加。因此，应在生物处理工艺之后采用适当的深度物理化学处理工艺，如活性炭吸附，以满足更严格的排放标准并对环境更安全。
