New insights into the rapid formation of initial membrane fouling after in-situ cleaning in a membrane bioreactor. (March 2019)

• Record Type: Journal Article
• Authors: Sun, Ming; Yan, Linlin; Zhang, Lanhe; Song, Lianfa; Guo, Jingbo; Zhang, Haifeng
• Is Part Of: Process biochemistry. Volume 78(2019)
• Page Start: 108
• Page End: 113
• Publication Date: 2019-03
• Subjects: Membrane bioreactor -- In-situ membrane cleaning -- Extracellular polymeric substances -- Interactions energy -- Membrane fouling potential; Biochemical engineering -- Periodicals; Biotechnology -- Periodicals; Biochemistry -- periodicals; Biotechnology -- periodicals; Chemical Engineering -- periodicals; Génie biochimique -- Périodiques; Biotechnologie -- Périodiques; Biochemical engineering; Biotechnology; Periodicals; 660.63
• DOI: 10.1016/j.procbio.2019.01.004
• Languages: English
• ISSNs: 1359-5113

Abstract

Graphical abstract: Highlights: The sludge after in-situ cleaning promotes the rapid formation of initial fouling. The sludge after in-situ cleaning had a high protein content in the EPS layers. The sludge after in-situ cleaning had higher adhesive and cohesive abilities. Abstract: In-situ chemical cleaning with sodium hypochlorite (NaClO) is often employed for maintaining constant permeability in a membrane bioreactor (MBR). In this study, the effect of NaClO shock on the rapid formation of initial membrane fouling was investigated over the course of the in-situ cleaning of a MBR. Variations of trans-membrane pressure (TMP) in the different runs indicated that the bulk sludge after NaClO-shock promotes the rapid formation of initial membrane fouling. After in-situ cleaning, the sludge had a high protein content in different extracellular polymeric substance layers and a substantial deterioration in sludge filterability compared to raw sludge. Based on the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory, NaClO shock significantly changes the surface properties of raw sludge. It reduces the surface electron donor component ( γ − ) and increases surface hydrophobicity. The sludge after NaClO-shock exhibited a stronger adhesive energy with the membrane and higher self-cohesive ability, resulting in severe membrane fouling.