School of Environment, Tsinghua University, Beijing 100084, China.
School of Environment, Tsinghua University, Beijing 100084, China; Department of Civil Engineering, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region.
Sci Total Environ. 2024 Jul 1;932:172982. doi: 10.1016/j.scitotenv.2024.172982. Epub 2024 May 3.
In recent decades, the presence of perfluoroalkyl acids (PFAAs) in municipal solid waste leachate has emerged as a growing concern. Research has focused on PFAA release and occurrence characteristics in landfill and waste-to-energy leachate, highlighting their significant impact when released into wastewater treatment plants. Given the extremely high loading rate faced by current on-site leachate treatment plants (LTPs), the objective of this study is to assess whether the current "anaerobic/aerobic (A/O) + membrane bioreactor (MBR) + nanofiltration (NF) + reverse osmosis (RO)" configuration is effective in PFAAs removal. Concentrations of raw and treated leachate in 10 on-site LTPs with same treatment configuration and varying landfill ages were measured, and a comprehensive mass flow analysis of each treatment process was conducted. The results indicate that A/O treatment has limited capacity for PFAA removal, while NF and RO processes reached 77.44 % and 94.30 % removal rates of ∑PFAAs concentration, respectively. Short-chain PFAAs (> 80 % detected frequency) primarily influenced the distribution and variations of PFAAs in leachate and tend to disperse in the water phase. Correlation analysis revealed the current on-site LTPs exhibit a more efficient removal capacity for long-chain PFAAs.
近几十年来，全氟烷基酸（PFAAs）在城市固体废物渗滤液中的存在已成为一个日益严重的问题。研究主要集中在填埋场和垃圾焚烧渗滤液中 PFAA 的释放和出现特征，强调了当它们释放到污水处理厂时的重大影响。鉴于当前现场渗滤液处理厂（LTP）面临的极高负荷率，本研究的目的是评估当前的“厌氧/好氧（A/O）+膜生物反应器（MBR）+纳滤（NF）+反渗透（RO）”配置是否能有效去除 PFAAs。对具有相同处理配置和不同填埋年龄的 10 个现场 LTP 的原始和处理后的渗滤液浓度进行了测量，并对每个处理过程进行了全面的质量流量分析。结果表明，A/O 处理对 PFAA 的去除能力有限，而 NF 和 RO 过程对∑PFAAs 浓度的去除率分别达到了 77.44%和 94.30%。短链 PFAAs（>80%检测频率）主要影响渗滤液中 PFAAs 的分布和变化，并且倾向于分散在水相中。相关分析表明，当前的现场 LTP 对长链 PFAAs 具有更高的去除能力。
