Shao Li-Ming, Deng Ying-Tao, Qiu Jun-Jie, Lü Fan, Zhang Hua, He Pin-Jing
Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China.
Huan Jing Ke Xue. 2021 Mar 8;42(3):1469-1476. doi: 10.13227/j.hjkx.202007263.
Properties of landfill leachate are complex. Therefore, leachate should be treated by combined processes with both biological and advanced methods. Due to the shortage of engineering-scale assessment data about the pollutant treatment contribution of individual process units, existing optimization methods still lack theoretical support. Here, a membrane biological reactor (MBR)+nanofiltration (NF) system with a capacity of 800 m·d was examined. Conventional physiochemical parameters and fluorescent parameters were examined to analyze the contribution of each process unit to treating mature landfill leachate. Furthermore, the transformation of dissolved organic matter (DOM) was evaluated using excitation emission matrix fluorescence spectroscopy-parallel factor (EEMs-PARAFAC). Results showed that the biological treatment removed soluble nitrogen (dissolved nitrogen, DN) by 74.7%, 54.6% occurred in the first-stage denitrification unit. The external ultrafiltration unit reduced dissolved chemical oxygen demand (COD) and dissolved organic carbon (DOC) by 92.2% and 93.3%, respectively. The nanofiltration unit effectively removed heavy metals and salts. Based on the tracking of DOM using fluorescent parameters, the first-stage denitrification unit was found to remove 75.4% of protein-like substances. The ultrafiltration unit mainly retained DOM with high hydrophilicity, while humus with high aromaticity was mainly retained by nanofiltration. The higher the degree of humification, the better the interception effect that was obtained. This indicates that biological treatment using the MBR process can be simplified, and ultrafiltration should prove reliable at preventing clogging during the treatment of mature landfill leachate.
垃圾渗滤液的性质复杂。因此，渗滤液应采用生物和高级方法相结合的工艺进行处理。由于缺乏关于各个工艺单元污染物处理贡献的工程规模评估数据，现有的优化方法仍缺乏理论支持。在此，对一个处理能力为800立方米/天的膜生物反应器（MBR）+纳滤（NF）系统进行了研究。检测了常规理化参数和荧光参数，以分析各工艺单元对处理成熟垃圾渗滤液的贡献。此外，利用激发发射矩阵荧光光谱-平行因子分析法（EEMs-PARAFAC）评估了溶解有机物（DOM）的转化情况。结果表明，生物处理去除了74.7%的可溶性氮（溶解态氮，DN），其中54.6%发生在一级反硝化单元。外置超滤单元分别将溶解化学需氧量（COD）和溶解有机碳（DOC）降低了92.2%和93.3%。纳滤单元有效去除了重金属和盐分。基于荧光参数对DOM的追踪发现，一级反硝化单元去除了75.4%的类蛋白质物质。超滤单元主要截留高亲水性的DOM，而高芳香性的腐殖质主要被纳滤截留。腐殖化程度越高，截留效果越好。这表明采用MBR工艺的生物处理可以简化，并且超滤在处理成熟垃圾渗滤液过程中应能可靠地防止堵塞。
