工程规模长填龄渗滤液膜生物-纳滤组合设施各单元污染物去除效能

填埋场渗滤液性质复杂,普遍采用生物处理与深度处理多单元串联工艺;但是,因缺乏对工程运行规模中各单元污染物处理贡献的评估数据,使优化单元组合方式缺少理论依据.因此,本文采用常规和荧光光谱指标结合的方法,对以采用“膜生物反应器(membrane biological reactor,MBR)+纳滤(nanofihratio...

Pollutant Removal Efficiency of Different Units Along a Mature Landfill Leachate Treatment Process in a Membrane Biological Reactor-Nanofiltration Combined Facility

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 m³·d^-1 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.