Modeling the influence of temperature on gel-enhanced concentration polarization in reverse osmosis Original Research Article

Model for concentration polarization enhanced by gel accumulated at membrane surface has been proposed. It provides distribution of concentration in the liquid phase and within the gel layer. Model allows analyzing the influence of thickness of fouling layer on the CP degree, surface concentration, osmotic pressure and membrane permeability. The model is based on the following assumptions: (1) the fluid is incompressible, continuous and isothermal with uniform density field under the steady-state conditions; (2) process is accompanied by accumulation of gel layer at membrane surface along with concentration polarization; (3) diffusion layer and deposited gel contains different components and are characterized by different values of diffusivity coefficients; (4) correlation for effective hindered back diffusion coefficient within deposited layer based on published data is used in the study; (5) transverse transport is based on the following mechanisms: convection due to the pressure difference and back diffusion owing to the concentration gradient.