Modeling of colloidal fouling in forward osmosis membrane: Effects of reverse draw solution permeation

Abstract A numerical model for predicting the flux decline due to colloidal fouling was developed for a forward osmosis (FO) membrane system. We derived the kinetic equation of the cake layer growth based on a first-order reaction and control volume approach. Based on the model simulation, it was found that the deposited particles on a membrane surface are proportional to the feed concentration and the permeate flux. Moreover, the simulation result reveals that the cake-enhanced osmotic pressure (CEOP) is a key factor diminishing the permeate flux for large colloidal foulants. For small colloidal foulants, the hydraulic resistance of the cake layer is dominant in flux decline at the beginning of the fouling and CEOP increasingly become significant as fouling progresses. The effects of the reverse draw solute permeation on the flux decline were also simulated. Interestingly, the increased reverse draw solute permeation obtained by increasing the solute permeability showed little effect on the flux decline. Contrarily, variation of the diffusivity significantly influenced the flux decline. Consequently, the numerical model developed in this paper suggests that the selection of draw solute for an FO membrane process should be carefully regarded, along with the fouling mechanism.

[1]  Benny D. Freeman,et al.  Reverse osmosis desalination: water sources, technology, and today's challenges. , 2009, Water research.

[2]  Gurdev Singh,et al.  Impact of feed water acidification with weak and strong acids on colloidal silica fouling in ultrafiltration membrane processes. , 2008, Water research.

[3]  Menachem Elimelech,et al.  Comparison of fouling behavior in forward osmosis (FO) and reverse osmosis (RO) , 2010 .

[4]  Michael Flynn,et al.  Membrane contactor processes for wastewater reclamation in space Part I. Direct osmotic concentration as pretreatment for reverse osmosis , 2005 .

[5]  Pierre Aimar,et al.  Model for colloidal fouling of membranes , 1995 .

[6]  J. G. Wijmans,et al.  The solution-diffusion model: a review , 1995 .

[7]  Tong Zhan,et al.  Flux patterns and membrane fouling propensity during desalination of seawater by forward osmosis. , 2012, Water research.

[8]  M. Elimelech,et al.  Cake-enhanced concentration polarization: a new fouling mechanism for salt-rejecting membranes. , 2003, Environmental science & technology.

[9]  Amy E. Childress,et al.  Forward osmosis: Principles, applications, and recent developments , 2006 .

[10]  How Yong Ng,et al.  Influence of colloidal fouling on rejection of trace organic contaminants by reverse osmosis , 2004 .

[11]  Qian Yang,et al.  Dual-layer hollow fibers with enhanced flux as novel forward osmosis membranes for water production. , 2009, Environmental science & technology.

[12]  Menachem Elimelech,et al.  Influence of Crossflow Membrane Filter Geometry and Shear Rate on Colloidal Fouling in Reverse Osmosis and Nanofiltration Separations , 2002 .

[13]  Edward L Cussler,et al.  Diffusion: Mass Transfer in Fluid Systems , 1984 .

[14]  Joon Ha Kim,et al.  Site-specific raw seawater quality impact study on SWRO process for optimizing operation of the pressurized step , 2009 .

[15]  Menachem Elimelech,et al.  Reverse draw solute permeation in forward osmosis: modeling and experiments. , 2010, Environmental science & technology.

[16]  Menachem Elimelech,et al.  Combined influence of natural organic matter (NOM) and colloidal particles on nanofiltration membrane fouling , 2005 .

[17]  Qian Yang,et al.  Enhanced forward osmosis from chemically modified polybenzimidazole (PBI) nanofiltration hollow fiber membranes with a thin wall , 2009 .

[18]  Anthony G Fane,et al.  Fouling propensity of forward osmosis: investigation of the slower flux decline phenomenon. , 2010, Water science and technology : a journal of the International Association on Water Pollution Research.

[19]  Minkyu Park,et al.  Determination of a constant membrane structure parameter in forward osmosis processes , 2011 .

[20]  J. McCutcheon,et al.  Influence of concentrative and dilutive internal concentration polarization on flux behavior in forward osmosis , 2006 .

[21]  Suzanne A Pierce,et al.  The energy challenge , 2008, Nature.

[22]  Anthony G. Fane,et al.  The effect of imposed flux on biofouling in reverse osmosis: Role of concentration polarisation and biofilm enhanced osmotic pressure phenomena , 2008 .

[23]  Lianfa Song,et al.  A new normalization method for determination of colloidal fouling potential in membrane processes. , 2004, Journal of colloid and interface science.

[24]  Dezhong Xiao,et al.  The role of physical and chemical parameters on forward osmosis membrane fouling during algae separa , 2011 .

[25]  Vicki Chen,et al.  Investigations of the coupled effect of cake-enhanced osmotic pressure and colloidal fouling in RO using crossflow sampler-modified fouling index ultrafiltration , 2011 .

[26]  M. Elimelech,et al.  Organic fouling of forward osmosis membranes: Fouling reversibility and cleaning without chemical reagents , 2010 .

[27]  Chuyang Y. Tang,et al.  Relating reverse and forward solute diffusion to membrane fouling in osmotically driven membrane processes. , 2012, Water research.

[28]  Anthony G Fane,et al.  Colloidal interactions and fouling of NF and RO membranes: a review. , 2011, Advances in colloid and interface science.

[29]  Menachem Elimelech,et al.  Chemical and physical aspects of organic fouling of forward osmosis membranes , 2008 .

[30]  Yaolin Liu,et al.  Combined fouling of forward osmosis membranes: Synergistic foulant interaction and direct observation of fouling layer formation , 2012 .

[31]  Tzahi Y Cath,et al.  Bidirectional permeation of electrolytes in osmotically driven membrane processes. , 2011, Environmental science & technology.

[32]  M. Elimelech,et al.  COLLOIDAL FOULING OF REVERSE OSMOSIS MEMBRANES , 1994 .

[33]  Menachem Elimelech,et al.  Colloidal fouling in forward osmosis: Role of reverse salt diffusion , 2012 .

[34]  D.J.H. Harmsen,et al.  Membrane fouling and process performance of forward osmosis membranes on activated sludge , 2008 .

[35]  Chuyang Y. Tang,et al.  Coupled effects of internal concentration polarization and fouling on flux behavior of forward osmosis membranes during humic acid filtration , 2010 .

[36]  V. Tarabara,et al.  Coupled effects of colloidal deposition and salt concentration polarization on reverse osmosis membrane performance , 2007 .

[37]  A. Kim,et al.  A new model for calculating specific resistance of aggregated colloidal cake layers in membrane filtration processes , 2005 .

[38]  Menachem Elimelech,et al.  Gypsum scaling and cleaning in forward osmosis: measurements and mechanisms. , 2010, Environmental science & technology.

[39]  Minkyu Park,et al.  Simulation of forward osmosis membrane process: Effect of membrane orientation and flow direction of feed and draw solutions , 2011 .

[40]  Gurdev Singh,et al.  Cake Compressibility of Silica Colloids in Membrane Filtration Processes , 2006 .

[41]  Anthony G. Fane,et al.  Implications of critical flux and cake enhanced osmotic pressure (CEOP) on colloidal fouling in reverse osmosis: Experimental observations , 2008 .

[42]  J. Georgiadis,et al.  Science and technology for water purification in the coming decades , 2008, Nature.