Water Desalination and Reuse Research Center and Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia.
Water Res. 2013 Oct 1;47(15):5447-63. doi: 10.1016/j.watres.2013.06.033. Epub 2013 Jun 27.
Biofouling in membrane bioreactors (MBRs) remains a primary challenge for their wider application, despite the growing acceptance of MBRs worldwide. Research studies on membrane fouling are extensive in the literature, with more than 200 publications on MBR fouling in the last 3 years; yet, improvements in practice on biofouling control and management have been remarkably slow. Commonly applied cleaning methods are only partially effective and membrane replacement often becomes frequent. The reason for the slow advancement in successful control of biofouling is largely attributed to the complex interactions of involved biological compounds and the lack of representative-for-practice experimental approaches to evaluate potential effective control strategies. Biofouling is driven by microorganisms and their associated extra-cellular polymeric substances (EPS) and microbial products. Microorganisms and their products convene together to form matrices that are commonly treated as a black box in conventional control approaches. Biological-based antifouling strategies seem to be a promising constituent of an effective integrated control approach since they target the essence of biofouling problems. However, biological-based strategies are in their developmental phase and several questions should be addressed to set a roadmap for translating existing and new information into sustainable and effective control techniques. This paper investigates membrane biofouling in MBRs from the microbiological perspective to evaluate the potential of biological-based strategies in offering viable control alternatives. Limitations of available control methods highlight the importance of an integrated anti-fouling approach including biological strategies. Successful development of these strategies requires detailed characterization of microorganisms and EPS through the proper selection of analytical tools and assembly of results. Existing microbiological/EPS studies reveal a number of implications as well as knowledge gaps, warranting future targeted research. Systematic and representative microbiological studies, complementary utilization of molecular and biofilm characterization tools, standardized experimental methods and validation of successful biological-based antifouling strategies for MBR applications are needed. Specifically, in addition, linking these studies to relevant operational conditions in MBRs is an essential step to ultimately develop a better understanding and more effective and directed control strategy for biofouling.
生物污染在膜生物反应器（MBR）中仍然是一个主要挑战，尽管 MBR 在全球范围内得到了越来越多的认可。关于膜污染的研究在文献中非常广泛，在过去 3 年中，有超过 200 篇关于 MBR 污染的出版物；然而，生物污染控制和管理方面的实际改进却非常缓慢。常用的清洗方法只是部分有效，膜更换往往变得频繁。生物污染控制取得成功的进展缓慢的原因主要归因于涉及的生物化合物的复杂相互作用，以及缺乏用于评估潜在有效控制策略的代表性实践实验方法。生物污染是由微生物及其相关的胞外聚合物（EPS）和微生物产物驱动的。微生物及其产物聚集在一起形成基质，这些基质在传统的控制方法中通常被视为一个黑匣子。基于生物的防污策略似乎是一种有效的综合控制方法的有前途的组成部分，因为它们针对生物污染问题的本质。然而，基于生物的策略仍处于发展阶段，需要解决几个问题，为将现有和新信息转化为可持续和有效的控制技术制定路线图。本文从微生物学角度研究 MBR 中的膜生物污染，以评估基于生物的策略在提供可行的控制替代方案方面的潜力。现有控制方法的局限性强调了采用综合防污方法的重要性，包括生物策略。这些策略的成功开发需要通过适当选择分析工具和组装结果来对微生物和 EPS 进行详细表征。现有的微生物学/EPS 研究揭示了一些影响以及知识差距，需要未来进行有针对性的研究。需要进行系统和有代表性的微生物学研究，互补利用分子和生物膜表征工具、标准化实验方法以及验证 MBR 应用中成功的基于生物的防污策略。具体而言，此外，将这些研究与 MBR 中的相关运行条件联系起来是最终开发出更好的理解和更有效、更有针对性的生物污染控制策略的必要步骤。
