The regenerative role of biofilm in the removal of pesticides from stormwater in biochar-amended biofilters
The regenerative role of biofilm in the removal of pesticides from stormwater in biochar-amended biofilters
复制标题
生物炭改良生物滤池中生物膜在去除雨水中农药的再生作用
DOI：
10.1039/d1ew00870f
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发表时间：
2022-03-30
影响因子：
5
通讯作者：
Higgins, Christopher P.
中科院分区：
文献类型：
--
作者：
Portmann, Andrea C.;LeFevre, Gregory H.;Higgins, Christopher P.
低影响的绿色基础设施系统，如生物过滤器，特别是在用生物炭改进后，可以帮助解决通过雨水输送的化学污染，这种污染日益对水生生态系统和地下水质量构成威胁。尽管已经研究了通过生物炭改良系统去除有机污染物（包括农药），但生物污垢层对污染物去除、生物转化和过滤器寿命的作用仍然知之甚少。本研究评估了通过完全耗尽污染物去除能力，生物活性生物炭修正柱中农药莠去津、吡虫啉和噻虫胺的去除效果。结果数据表明生物过程占生物炭修正砂柱总体去除量的 20-36%。此外，采用液相色谱四极杆飞行时间质谱 (LC-QToF-MS) 组合目标和可疑筛选方法来评估这三种农药的潜在转化和转化产物 (TP) 的释放。在实验期间，废水中检测到的所有 TP 均低于其各自母体进水浓度的 2.5%。此外，在生物炭施用率为 0.5 wt% 时，与结垢但不活跃的过滤器相比，活性生物膜的存在将过滤器寿命延长了 1.8-2.3 倍，其中去除可能仅以吸附为主。情景模型估计表明，在代表性案例研究中，生物炭改良的生物过滤器在生物炭施用率低至 1 wt% (5 vol%) 时可以持续至少 17 年，然后才会超过水生生物阈值。这项研究的结果为生物炭改良生物过滤器中农药总磷的形成和过滤器寿命的估计提供了新的见解。
Low-impact, green infrastructure systems such as biofilters, particularly when amended with biochar, can help address chemical pollution conveyed via stormwater that is increasingly posing a threat to aquatic ecosystems and groundwater quality. Although removal of organic contaminants including pesticides by biochar-amended systems has been studied, the role of a biofouling layer on contaminant removal, biotransformation, and filter lifetime remains poorly understood. This study evaluated the removal of the pesticides atrazine, imidacloprid, and clothianidin in biologically active biochar-amended columns through complete exhaustion of contaminant removal capacity. The resultant data indicate that biological processes accounted for 20-36% of overall removal in the biochar-amended sand columns. In addition, a combined target and suspect screening approach using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QToF-MS) was employed to evaluate the potential transformation of these three pesticides and release of the transformation products (TPs). All TPs detected in the effluent remained below 2.5% of their respective parent influent concentrations for the duration of the experiment. Furthermore, at a biochar application rate of 0.5 wt%, the presence of an active biofilm prolonged the filter lifetime by 1.8-2.3 times compared to a fouled but inactive filter, where removal was presumably dominated by adsorption only. Scenario modelling estimates showed that biochar-amended biofilters could last at least 17 years before exceeding aquatic life threshold values at biochar-application rates as low as 1 wt% (5 vol%) in a representative case study. Results of this study provide novel insight on pesticide TP formation in biochar-amended biofilters and estimation of filter lifetimes.