【作者】 覃芳慧；

【导师】 周少奇；

【作者基本信息】 华南理工大学 ， 环境工程， 2011， 硕士

【摘要】 垃圾渗滤液是垃圾堆放过程中产生的高浓度有机废水。因其具有污染物浓度高、成分复杂、水质水量变化大等特点,经过生化处理后仍有难降解的有机物残留,难以达标排放。随着垃圾渗滤液对周围环境的污染问题日益严重,以及新标准--《生活垃圾填埋场污染物控制标准（GB16887-2008）》的颁布,亟需探索经济、高效的垃圾渗滤液深度处理技术。针对垃圾渗滤液中高浓度难降解有机物难处理的问题,本论文在进行实际工程分析的基础上,开展了物化-生物深度处理工艺的研究,提出Fenton-双泥SBR组合工艺,以探讨渗滤浓缩液的深度处理技术。首先分析实际工程中,组合工艺对垃圾渗滤液的处理效果。通过对渗滤液中溶解性有机物质（DOM）的分离以及采用GC-MS联用仪对垃圾渗滤液中的有机微污染物的鉴定。结果表明,经过生物-物化处理,出水水质达标排放。其次通过单因素分析实验确定Fenton法处理渗滤液的最佳条件,分析反应过程中氧化、混凝作用对COD和腐殖酸的去除特性,同时初步探讨Fenton氧化降解机理。结果表明,Fenton试剂处理渗滤液的最佳条件:反应时间为2h,初始pH值为4.0,Fe²⁺的投量为40mM,H₂O₂的投量为120mM。Fenton试剂能有效去除高浓度的腐殖酸,大部分的腐殖酸被Fenton试剂氧化降解为低分子的有机物而不是完全矿化生成CO₂和水。COD的变化曲线与腐殖酸的相似,但腐殖酸的去除率要高于COD大约30%,说明腐殖酸的去除对整体污染物的去除具有决定性的作用。Fenton试剂处理渗滤浓缩液主要通过混凝作用和氧化作用。因不同的[H₂O₂]/[Fe²⁺]摩尔比而有显著差异。在低[H₂O₂]/[Fe²⁺]摩尔比（≤0.5）时,反应机制是促进的絮凝作用;在[H₂O₂]/[Fe²⁺]摩尔比为1～6时,反应机制是兼有氧化和絮凝沉淀作用;在高[H₂O₂]/[Fe²⁺]摩尔比（≥6）时,反应机制是氧化作用。最后研究双泥SBR对Fenton处理后的浓缩液与模拟生活污水混合液的去除效果。经过Fenton试剂处理,浓缩液的可生化性提高,生物毒性降低,为后续生物处理创造良好条件。结果表明,模拟生活污水的混入可有效提高Fenton后浓缩液的可生化性,反应器对混合液中COD、TN、NH3-N和腐殖酸的平均去除率分别为85.2%、75.5%、70.4%和70.3%。出水COD、氨氮和总氮能够达标排放,有效解决了浓缩液高浓度难生物降解有机物和TN去除的难题。更多还原

【Abstract】 Landfill leachate is one kind of organic wastewater with high concentration which produced in the process of refuse disposal. The landfill leachate contains a variety of organic, inorganic and heavy metal contents, which are high in concentration and often influenced by the age and type of solid wastes of the landfill site. Therefore, there still have much refractory contaminant in the leachate after the biochemical treatment and the effluent can’t meet relevant standards. And with a potential risk and potential hazards towards the public healthy and ecosystems and the launch of the new Standard for Pollution Control on the Landfill Site of Municipal Solid Waste（GB16887-2008）, finding an economic and effective way to treat landfill leachate properly becomes an urgent and challenging task to local gocernments. This study is carried out to investigate the feasibility of chemical-biological （Fenton reagent+Two sludge SBR） combined technology in treating landfill leachate so as to meet the newly launched discharge limit of landfill leachate.Firstly, the transformation of pollutions including humic substances, microorganic pollutants in landfill leachate treated by a combined technology were investigated by fractionation technology of dissolved organic matters （DOM） and gas chromatography-mass spectroscopy （GC-MS） analysis. The observations indicated that landfill leachate was treated effectivly by the combined process .Secondly , the optimum process condition for treatment of landfill leachate by Fenton reagent are achieved. Just as follow: the initial pH value of 4, reaction time of 2h, H₂O₂ dosge of 120Mm and H₂O₂/Fe²⁺ molar ratio of 3:1. The change curves of humic acids removal were similar to those of COD. The removal of humic acids was 30% higher than removal of COD, which indicated that humic acids was mostly degraded into various intermediate organic compounds but not mineralized by Fenton reagent. In addition, our study was focus on the oxidation and coagulation performances of Fenton treatment on chemical oxygen demand （COD） and humic substances removal in leachate. The mechanism of COD and humic acids removed by Fenton reagent was significantly different according to the [H₂O₂]/[Fe²⁺] molar ratio. With low ratio of [H₂O₂]/[Fe²⁺] （≤0.5 ）, the Fenton reaction was coagulation enhanced by H₂O₂. With high ratio of [H₂O₂]/[Fe²⁺] （≥6 ）, the Fenton reaction was oxidation while H₂O₂ oxidation catalyzed by Fe²⁺. With medium ratio of [H₂O₂]/[Fe²⁺] （0.5～6）, the Fenton reaction could be characterized into two speciffic systems: oxidation and coagulation.Finally, the feasibility of treating mixture of landfill leachate and synthetic wastewater was studied using two-sludge SBR systems. The results showed that the addition of carbon with addition of synthetic wastewater could effectively enhance the reduction rate of TN. And the average removal efficiencies for COD, NH3-N, TN and humic substances were 85.2%, 75.5%, 70.4% and 70.3% respectively. The combined advanced treatment of Fenton oxidation process followed Two-sludge SBR could remove high concentration of humic substances effectively.更多还原