Amity Institute of Microbial Technology, Amity University Rajasthan, Jaipur, 303002, India.
Department of Microbiology, Savitribai Phule Pune University, Pune, Maharashtra, 411007, India.
Appl Biochem Biotechnol. 2023 Mar;195(3):2114-2133. doi: 10.1007/s12010-022-04261-4. Epub 2022 Nov 17.
Biofouling roots damage to membrane bioreactors (MBRs), such as physical, functional and organisational changes and even therefore clogging of the membrane pores and successive microbial degradation. Further, it blocks the pores, results into a biomass cake and in due course reduces the membrane flux and leads to an increase in the operational costs. MBR fouling contributed to the rise in transmembrane pressure (TMP) and decrease in permeate flux (in case of constant pressure operation mode). Chemical surfactants adopted for the cleaning of membrane surfaces have certain disadvantages such as toxicity manifestations, damage to the membranes and high CMC concentrations. Biosurfactant surfactants have attained increasing interest due to their low toxicity, biodegradability, stability to extreme environmental conditions such as temperatures, pH and tolerance to salinity. The biosurfactants trapped the foulants via micelle formation, which distresses hydrophobic interactions amongst bacteria and the surface. Rhamnolipids as an anionic biosurfactant pose a significant interfacial potential and have affinity to bind organic matter. The present review discusses the problem of biofouling in MBRs, type and interactions of foulants involved and also highlights the mechanisms of biosurfactant cleaning, effect of different parameters, effect of concentration, TMP, flux recovery, permeability, mitigation practices and challenges.
生物污垢会对膜生物反应器（MBR）造成损害，例如物理、功能和组织变化，甚至导致膜孔堵塞和随后的微生物降解。此外，它会堵塞毛孔，形成生物量饼，并最终降低膜通量，并导致运营成本增加。MBR 污垢会导致跨膜压力（TMP）升高和渗透通量下降（在恒压操作模式下）。用于清洁膜表面的化学表面活性剂具有一定的缺点，例如表现出毒性、对膜的损害以及 CMC 浓度高。生物表面活性剂由于其低毒性、生物降解性、对极端环境条件（如温度、pH 值和耐盐性）的稳定性而受到越来越多的关注。生物表面活性剂通过胶束形成捕获污垢，从而减轻细菌和表面之间的疏水相互作用。鼠李糖脂作为一种阴离子生物表面活性剂具有显著的界面势能，并具有与有机物结合的亲和力。本综述讨论了 MBR 中的生物污垢问题，涉及的污垢类型和相互作用，并强调了生物表面活性剂清洁的机制、不同参数的影响、浓度、TMP、通量恢复、渗透率、缓解措施和挑战。
