Lei Yangming, Shen Zhemin, Huang Renhua, Wang Wenhua
School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China.
Water Res. 2007 Jun;41(11):2417-26. doi: 10.1016/j.watres.2007.02.044. Epub 2007 Apr 16.
Two-stage aged-refuse bioreactor (ARB) was applied to treat landfill leachate in Shanghai Waste Laogang Disposal Plant. The removal efficiencies of chemical oxygen demand (COD), biological oxygen demand (BOD), total organic carbon (TOC), total nitrogen (TN) and ammonia nitrogen (NH(3)-N) of landfill leachate treated by the two-stage bioreactor system were 98.5%, 99.9%, 98.0%, 64.2% and 99.9%, respectively. The COD and BOD in the second stage effluent were 239 and 7 mg l(-1), respectively. Thus three types of electrolysis were employed to further treat the second effluent, undivided electrolysis (UDE), divided electrolysis (DE) with Ti/PbO(2) cathode and DE with gas diffusion cathode. All electrolysis processes possessed good color removal effect, while the DE with gas diffusion cathode had the best TOC removal effect. The optimum electrolysis time of leachate was 30 min. The TOC removal efficiencies were 51.4% and 39.7% in anolyte and catholyte, respectively, after 30 min electrolysis at 5 V. In addition, the DE with gas diffusion cathode showed the least energy consumption of 9.8 k Whm(-3) at 30 min. The organic pollutants in the leachate were analyzed through a gas chromatography coupled with mass spectrometry (GC-MS) system. Through the two-stage ARB, the species and concentrations of organic pollutants in landfill leachate reduced greatly. Several chlorinated organic compounds were detected in the effluent after the UDE and the anolyte of the DE. In addition, the concentration of absorbable organic halogens (AOX) increased greatly during the electrolysis. Hence, careful consideration should be given in the application of electro-oxidation into the treatment of chloride-containing wastewater.
采用两级陈化垃圾生物反应器（ARB）处理上海老港垃圾处理厂的垃圾渗滤液。两级生物反应器系统处理后的垃圾渗滤液中化学需氧量（COD）、生化需氧量（BOD）、总有机碳（TOC）、总氮（TN）和氨氮（NH₃-N）的去除率分别为98.5%、99.9%、98.0%、64.2%和99.9%。第二级出水的COD和BOD分别为239和7 mg l⁻¹。因此，采用了三种类型的电解来进一步处理第二级出水，即无隔膜电解（UDE）、以Ti/PbO₂为阴极的有隔膜电解（DE）和气体扩散阴极的有隔膜电解。所有电解过程都具有良好的脱色效果，而气体扩散阴极的有隔膜电解对TOC的去除效果最佳。渗滤液的最佳电解时间为30分钟。在5 V下电解30分钟后，阳极液和阴极液中TOC的去除率分别为51.4%和39.7%。此外，气体扩散阴极的有隔膜电解在30分钟时能耗最低，为9.8 k Wh m⁻³。通过气相色谱-质谱联用（GC-MS）系统对渗滤液中的有机污染物进行了分析。通过两级ARB，垃圾渗滤液中有机污染物的种类和浓度大幅降低。在UDE后的出水和DE的阳极液中检测到了几种氯代有机化合物。此外，电解过程中可吸附有机卤素（AOX）的浓度大幅增加。因此，在将电氧化应用于含氯废水处理时应谨慎考虑。
