Abstract According to previous research, it has been proved that wastewater treatment plants (WWTPs) can retain more than 90 % of the MPs contained in wastewater. However, a significant fraction of the MPs removed in WWTPs is retained in the sludge floc and this may lead to an environmental issue since biosolids can be used as fertilizers. The purpose of this research was to evaluate how the presence of polyethylene (PE) could interfere with the activated sludge performance. For this, a sequencing batch reactor (SBR) was continuously fed during 93 days with synthetic sewage and PE microbeads. It was observed that 98 ± 2% of the total amount of MPs that entered SBR was accumulated in the activated sludge. Despite the high accumulation of MPs in the sludge, the depuration performance of the reactor was not compromised. However, the presence of MPs decreased the richness (Chao1) and abundance-based coverage estimators (ACE) and diversity (Shannon) of the bacterial community on day 93. Based on the analysis of the diversity indices and the relative abundances of microbial taxa, it was concluded that MPs had selective effects on activated sludge microbial community. However, MPs did not affect the abundance of nitrifying and denitrifying bacteria in the sludge.

中文翻译：

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聚乙烯微塑料对活性污泥过程的影响 - 在污泥中的积累以及对过程和生物质特性的影响

摘要 根据以往的研究，污水处理厂（WWTPs）可以截留废水中90%以上的MPs。然而，污水处理厂中去除的大部分 MP 保留在污泥絮凝物中，这可能会导致环境问题，因为生物固体可用作肥料。本研究的目的是评估聚乙烯 (PE) 的存在如何干扰活性污泥性能。为此，在 93 天内连续向序批式反应器 (SBR) 加入合成污水和 PE 微珠。据观察，进入 SBR 的 MPs 总量的 98±2% 积聚在活性污泥中。尽管污泥中 MP 的积累很高，但反应器的净化性能并未受到影响。然而，MPs 的存在降低了第 93 天细菌群落的丰富度 (Chao1) 和基于丰度的覆盖率估计量 (ACE) 和多样性 (Shannon)。得出结论，MPs 对活性污泥微生物群落具有选择性作用。然而，MPs 不影响污泥中硝化和反硝化细菌的丰度。