渗滤液场内处理的有机物去除特征和植物毒性评价

Study on Removal Characteristics of Organics in Leachates by Treatment Through Recirculation into Landfill and Their Phyto-toxicity Comparison

以3种不同处理水平的渗滤液为研究对象,从有机物去除特征和植物毒性角度研究通过渗滤液循环回灌和终场覆盖层灌溉2个单元处理生活垃圾填埋场渗滤液的可行性.结果表明,循环回灌对老港渗滤液中的小分子量亲水性物质类(HyI)有机物去除效果较好,去除率为91.2%;终场覆盖层灌溉对循环回灌出水中的高分子量腐殖质类(HS)有机物去除效果较佳,去除率为85.7%;两者串联组合的场内循环处理工艺对老港渗滤液中的溶解性有机物(DOM)去除率高达96.9%,且对HS和HyI均具较高的去除效果,去除率分别为96.6%和97.0%;循环回灌和覆盖层灌溉这2个处理单元还具有梯级降低渗滤液植物毒性的作用.

Leachate from the regulation pond of Laogang landfill in Shanghai, effluent from an anaerobic methanogenic landfill column for recirculating Laogang landfill leachate and effluent of the recireulated leachate further treated by irrigation through mimic final cover, were selected to determine the feasibility of landfill leachate treatment through recirculation and final cover irrigation. The evaluation was based on removal characteristics of organic in the three landfill leachate and their phyto-toxicity. The results show that high efficiency was achieved for HyI substance in Laogang leachate by recirculation, indicated by 91.2% removal rate. For recireulated leachate, 85.7% of humic substance was removed efficiently by irrigation on landfill final cover. When the two treatment units were combined together to treat Laogang leachate, the removal rate of DOM reached to 96.9% , both HS and Hyl were removed effectively, 96.6% and 97.0% removal rate achieved respectively. Phyto-toxicity of leachate intluent could be obviously alleviated by recirculation and final cover irrigation.