Department of Chemical and Environmental Engineering, Technical University of Cartagena, Paseo Alfonso XIII 44, E-30203 Cartagena, Spain.
Department of Chemical and Environmental Engineering, Technical University of Cartagena, Paseo Alfonso XIII 44, E-30203 Cartagena, Spain.
Mar Pollut Bull. 2020 Jul;156:111211. doi: 10.1016/j.marpolbul.2020.111211. Epub 2020 May 4.
This paper discusses about the role of two different wastewater treatment technologies in the abatement of microplastics (MPs) from the final effluent of an urban wastewater treatment plant (WWTP); i.e., membrane bioreactor technology (MBR) and rapid sand filtration (RSF). For this purpose, a WWTP with these two technologies was monitored for 18 months. The average microplastic concentration was 4.40 ± 1.01 MP L for the influent, 0.92 ± 0.21 MP L for MBR, and 1.08 ± 0.28 MP L for RSF, without statistically significant differences for MPs removal between both technologies (F-test = 0.195, p = 0.661). The main MP forms isolated in our study were fibers (1.34 ± 0.23 items L), followed by films (0.59 ± 0.24 items L), fragments (0.20 ± 0.09 items L), and beads (0.02 ± 0.01 items L). All of them probed to be statistically significant reduced after both technologies, but without statistically significant differences between them. The MP removal efficiency was 79.01% and 75.49% for MBR and RSF, respectively, although higher for microplastic particulate forms (MPPs), 98.83% and 95.53%, than for fibers, 57.65% and 53.83% for MBR and RSF, respectively, displaying a selective removal of particulate forms against microfibers. Fourteen different plastic polymers were identified in the influent, only persisting low-density polyethylene (LDPE), nylon (NYL), and polyvinyl (PV) in RSF effluent, and melamine (MUF) after MBR treatment. The MP size ranged from 210 μm, corresponding to NYL fragment form in the influent, to 6.3 mm, corresponding to a red microfiber also from the influent. The maximum MP average size significantly decreased from MBR (1.39 ± 0.15 mm), to RSF (1.15 ± 0.08 mm) and influent (1.05 ± 0.05 mm) (F-test = 4.014, p = 0.019), exhibiting the fiber selection carried out by these advanced technologies for wastewater treatment.
本文讨论了两种不同的废水处理技术在减少城市污水处理厂（WWTP）最终出水中微塑料（MPs）方面的作用，即膜生物反应器技术（MBR）和快速砂滤技术（RSF）。为此，对采用这两种技术的 WWTP 进行了 18 个月的监测。进水的平均微塑料浓度为 4.40±1.01 MPs/L，MBR 为 0.92±0.21 MPs/L，RSF 为 1.08±0.28 MPs/L，两种技术对 MPs 的去除没有统计学上的显著差异（F 检验=0.195，p=0.661）。本研究中分离出的主要 MP 形态为纤维（1.34±0.23 个/L），其次为薄膜（0.59±0.24 个/L）、碎片（0.20±0.09 个/L）和小球（0.02±0.01 个/L）。所有这些形态在经过两种技术处理后均有统计学意义上的减少，但两者之间没有统计学意义上的差异。MBR 和 RSF 的 MP 去除效率分别为 79.01%和 75.49%，但对微塑料颗粒形态（MPPs）的去除效率更高，分别为 98.83%和 95.53%，而对纤维的去除效率分别为 57.65%和 53.83%，MBR 和 RSF 分别表现出对颗粒形态的选择性去除。在进水中共鉴定出 14 种不同的塑料聚合物，只有低密度聚乙烯（LDPE）、尼龙（NYL）和聚氯乙烯（PV）在 RSF 出水中残留，而经过 MBR 处理后则只有三聚氰胺（MUF）残留。MP 的尺寸范围从 210μm，对应进水中的 NYL 碎片形态，到 6.3mm，对应进水中的红色微纤维。MBR（1.39±0.15mm）、RSF（1.15±0.08mm）和进水（1.05±0.05mm）的 MP 平均尺寸显著减小（F 检验=4.014，p=0.019），表明这些先进的废水处理技术对纤维具有选择性。
