Abstract:

To investigate the removal and transformation patterns of dissolved organic matter(DOM) in the full quantization treatment of landfill leachate concentrate, this study centered on the landfill leachate concentrate derived from a waste transfer station in Shenzhen. The research comprehensively characterized the transformation of DOM at both macro and micro levels using spectroscopy and high-resolution mass spectrometry techniques. The transfer station employed a full quantization treatment process of “biochemical process+advanced oxidation process+biochemical process”, resulting in the significant reduction of the concentrate color, with COD and DOC removal rates exceeding 90%. Ultraviolet-visible spectrophotometry results indicated aromaticity of DOM was slightly increased after biochemical treatment and significantly reduced after UV/Fenton treatment. The excitation-emission matrices with parallel factor analysis results showed that the main fluorescent substances in the concentrates were humic substances and fulvic acids, and all the four identified fluorescence components could be completely removed after the full quantization treatment. The results of Orbitrap MS revealed that DOM was primarily composed of CHO substances and lignins/carboxyl-rich alicyclic substances, accounting for 61%-66% and 67%-72%, respectively. The initial biological process had a limited impact on DOC removal and transformation, with only a small amount of organic matters removal and generation observed. The UV/Fenton process, as the core technology in full quantization treatment, effectively removed large amount of organic pollutants. The removed substances were mainly concentrated in the lower oxidation degrees〔n(O)/n(C)<0.6〕, while the generated substances were mainly concentrated in the high oxidation degrees〔n(O)/n(C)>0.6〕. The subsequent biological process could further remove organic matters, with only a minor amount of product generation observed.

Key words: landfill leachate concentrate, full quantization treatment, biochemical treatment, advanced oxidation process, dissolved organic matter

摘要：

为探究垃圾渗滤液膜浓缩液在全量化处理过程中溶解性有机物（DOM）的去除和转化规律，以深圳某垃圾中转站渗滤液膜浓缩液作为研究对象，利用光谱和高分辨质谱技术全面表征了DOM在宏观和微观层面的转化特征。该中转站采用“生化+高级氧化+生化”的全量化处理工艺，处理后膜浓缩液色度明显降低，COD和DOC去除率均可达90%以上。紫外可见光谱表明，DOM的芳香性经生化处理后略有提高，而经紫外光/Fenton处理后又显著降低。三维荧光光谱-平行因子分析表明，膜浓缩液中荧光物质以腐殖质和黄腐酸为主，所识别出的4种荧光组分在经全量化工艺处理后可被完全去除。静电场轨道阱质谱分析表明，膜浓缩液DOM以CHO物质以及木质素/富羧基脂环类物质为主，其质量分数分别可达61%~66%和67%~72%。一生化工艺对DOM的去除及转化作用有限，处理过程中仅观察到少量有机物的去除和生成。紫外光/Fenton工艺作为全量化处理中的核心技术可大量去除有机污染物，且所去除的物质主要集中在更低氧化度区域〔n（O）/n（C）<0.6〕，生成的物质则主要集中于高氧化度区域〔n（O）/n（C）>0.6〕。二生化工艺处理能继续去除有机物，并且仅观察到少量产物生成。

关键词: 垃圾渗滤液膜浓缩液, 全量化处理, 生化处理, 高级氧化, 溶解性有机物

CLC Number: 

• X703