Development of a novel fouling suppression system in membrane bioreactors using an intermittent electric field.

A novel membrane bioreactor system that uses an intermittent electric field was successfully developed to suppress membrane fouling, caused mainly by activated sludge. We found that the surface of the activated sludge is negatively charged, and propose the utilization of an electric repulsive force to move the sludge away from the membrane by applying an electric field only when the permeate flux has drastically declined because of membrane fouling. The experimental results showed that a field of 6 V cm(-1), switched on and off every 90 s, significantly improved the removal of the activated sludge from the membrane and accordingly improved the average permeate flux.

[1]  D. G. Allen,et al.  Surface properties of sludge and their role in bioflocculation and settleability. , 2001, Water research.

[2]  C. Posten,et al.  Fractionation of proteins with two-sided electro-ultrafiltration. , 2007, Journal of biotechnology.

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

[4]  Yoshimasa Watanabe,et al.  Elimination of selected acidic pharmaceuticals from municipal wastewater by an activated sludge system and membrane bioreactors. , 2007, Environmental science & technology.

[5]  Carlos C. Tarazaga,et al.  Physical cleaning by means of electric field in the ultrafiltration of a biological solution , 2006 .

[6]  El Hani Bouhabila,et al.  Microfiltration of activated sludge using submerged membrane with air bubbling (application to wastewater treatment) , 1998 .

[7]  G. Belfort,et al.  A Predictive Aggregate Transport Model for Microfiltration of Combined Macromolecular Solutions and Poly‐Disperse Suspensions: Testing Model with Transgenic Goat Milk , 2003, Biotechnology progress.

[8]  R. G. Cox,et al.  The lateral migration of a spherical particle in two-dimensional shear flows , 1976, Journal of Fluid Mechanics.

[9]  Tatsuki Ueda,et al.  Effects of aeration on suction pressure in a submerged membrane bioreactor , 1997 .

[10]  Georges Belfort,et al.  A Predictive Aggregate Transport Model for Microfiltration of Combined Macromolecular Solutions and Poly‐Disperse Suspensions: Model Development , 2003, Biotechnology progress.

[11]  S. Yamanishi,et al.  Modeling of biofouling by extracellular polymers in a membrane separation activated sludge system , 1998 .

[12]  T. Murase,et al.  Analysis of filtration mechanism of dead-end electro-ultrafiltration for proteinaceous solutions , 1992 .

[13]  H. Yukawa,et al.  CHARACTERISTICS OF CROSS FLOW ELECTRO-ULTRAFILTRATION FOR COLLOIDAL SOLUTION OF PROTEIN , 1983 .

[14]  Andrew L. Zydney,et al.  Theoretical analysis of particle trajectories and sieving in a two-dimensional cross-flow filtration system , 2006 .

[15]  G. Jonsson,et al.  Electro-ultrafiltration of amylase enzymes: Process design and economy , 2007 .

[16]  H. Yukawa.  Study of Equation of Electro-Ultrafiltration for Colloidal Solution , 1980 .

[17]  T Higuchi,et al.  A model for membrane bioreactor process based on the concept of formation and degradation of soluble microbial products. , 2001, Water research.

[18]  K. Krauth,et al.  Replacement of secondary clarification by membrane separation — Results with plate and hollow fibre modules , 1998 .

[19]  Hang-Sik Shin,et al.  Sludge characteristics and their contribution to microfiltration in submerged membrane bioreactors , 2003 .

[20]  Simon Judd,et al.  Air sparging of a submerged MBR for municipal wastewater treatment , 2002 .