Water Desalination and Reuse Center, Biological and Environmental Science & Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia.
Water Desalination and Reuse Center, Biological and Environmental Science & Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
Proc Natl Acad Sci U S A. 2021 Sep 14;118(37). doi: 10.1073/pnas.2016529118.
Anaerobic membrane bioreactor (AnMBR) for wastewater treatment has attracted much interest due to its efficacy in providing high-quality effluent with minimal energy costs. However, membrane biofouling represents the main bottleneck for AnMBR because it diminishes flux and necessitates frequent replacement of membranes. In this study, we assessed the feasibility of combining bacteriophages and UV-C irradiation to provide a chemical-free approach to remove biofoulants on the membrane. The combination of bacteriophage and UV-C resulted in better log cells removal and ca. 2× higher extracellular polymeric substance (EPS) concentration reduction in mature biofoulants compared to either UV-C or bacteriophage alone. The cleaning mechanism behind this combined approach is by 1) reducing the relative abundance of spp. and selected bacteria (e.g., , , , and gram-positive Firmicutes) associated with the membrane biofilm and 2) forming cavities in the biofilm to maintain water flux through the membrane. When the combined treatment was further compared with the common chemical cleaning procedure, a similar reduction on the cell numbers was observed (1.4 log). However, the combined treatment was less effective in removing EPS compared with chemical cleaning. These results suggest that the combination of UV-C and bacteriophage have an additive effect in biofouling reduction, representing a potential chemical-free method to remove reversible biofoulants on membrane fitted to an AnMBR.
厌氧膜生物反应器(AnMBR)因其在提供高质量出水和最小能源成本方面的功效而受到广泛关注。然而,膜生物污染是 AnMBR 的主要瓶颈,因为它会降低通量并需要频繁更换膜。在这项研究中,我们评估了将噬菌体和 UV-C 照射相结合以提供一种无化学物质的方法来去除膜上生物污垢的可行性。与单独使用 UV-C 或噬菌体相比,噬菌体和 UV-C 的组合可更好地去除对数细胞,并且成熟生物污垢中的细胞外聚合物(EPS)浓度降低约 2 倍。这种组合方法的清洁机制是通过 1)减少与膜生物膜相关的 spp.和选定细菌(例如, , , ,和革兰氏阳性Firmicutes)的相对丰度,以及 2)在生物膜中形成空腔以保持水通量通过膜。当将联合处理与常见的化学清洗程序进一步比较时,观察到细胞数量的相似减少(1.4 对数)。然而,与化学清洗相比,联合处理在去除 EPS 方面的效果较差。这些结果表明,UV-C 和噬菌体的组合在减少生物污垢方面具有附加作用,代表了一种去除适合 AnMBR 的膜上可逆生物污垢的潜在无化学物质方法。