The role of blocking and cake filtration in MBR fouling

Abstract Membrane fouling in a side stream biomass separation MBR pilot plant was investigated. Constant flux filtration (18–721/M2h) was employed. Air was continuously supplied to the MBR system with the feed (sludge) to flush the membrane surface, and backwashing was applied every 5–10 min for 8 s to control membrane fouling. Although the duration of pore blocking was generally short (completed in 8 s at a flux of 52 llm2h), blocking resistance (mainly irreversible blocking resistance) was the main cause of membrane fouling. However, the resistance of the filter cake also played an important role, particularly when the backwashing interval was extended to 10 min. In terms of fouling reversibility, blocking resistance was not completely reversible by backwashing, especially at higher fluxes (e.g. 69 I/m2h), and frequent chemical cleaning (once every week at 401/m2h) was required. However, cake filtration was easily reversible via a combination of backwashing and sludge/air flushing of the membrane surface. Finally, a simple method to identify both irreversible and reversible blocking resistance and filter cake resistance was proposed.

[1]  T. Murakami,et al.  Application of immersed-type membrane separation activated sludge process to municipal wastewater treatment , 2000 .

[2]  Khalid Aziz,et al.  The Flow Of Complex Mixtures In Pipes , 2021 .

[3]  In-Soung Chang,et al.  Effects of membrane fouling on solute rejection during membrane filtration of activated sludge , 2001 .

[4]  Chung‐Hak Lee,et al.  Comparison of the filtration characteristics between attached and suspended growth microorganisms in submerged membrane bioreactor. , 2001, Water research.

[5]  Kazuo Yamamoto,et al.  Floc size distribution and bacterial activities in membrane separation activated sludge processes for small-scale wastewater treatment/reclamation , 1997 .

[6]  Michel Y. Jaffrin,et al.  Contribution of various constituents of activated sludge to membrane bioreactor fouling , 2000 .

[7]  Robert H. Davis,et al.  The behavior of suspensions and macromolecular solutions in crossflow microfiltration , 1994 .

[8]  Nazim Cicek,et al.  Effectiveness of the membrane bioreactor in the biodegradation of high molecular weight compounds , 1998 .

[9]  Pierre Côté,et al.  Immersed membrane activated sludge for the reuse of municipal wastewater , 1997 .

[10]  K. Hata,et al.  Domestic wastewater treatment by a submerged membrane bioreactor with gravitational filtration , 1999 .

[11]  Xia Huang,et al.  Effect of sludge retention time on microbial behaviour in a submerged membrane bioreactor , 2001 .

[12]  A. Grasmick,et al.  Floc size distribution in a membrane bioreactor and consequences for membrane fouling , 1998 .

[13]  El Hani Bouhabila,et al.  Fouling characterisation in membrane bioreactors , 2001 .

[14]  In-Soung Chang,et al.  Membrane filtration characteristics in membrane-coupled activated sludge system -- the effect of physiological states of activated sludge on membrane fouling , 1998 .