Electric field enhanced gel controlled cross-flow ultrafiltration under turbulent flow conditions

A theoretical analysis based on integral method for quantification of the permeate flux and mass transfer coefficient in gel layer controlled electric field enhanced cross-flow ultrafiltration considering developing mass transfer boundary layer under turbulent flow regimes is elaborated in the present work. Thin rectangular channel and tubular module are selected as system geometry. The analysis for tubular module is carried out for the experimental data of colloidal solution of gelatin available in the literature [H. Yukawa, K. Shimura, A. Maniwa, Cross flow electro-ultrafiltration for colloidal solution of protein, J. Chem. Eng. Jpn. 16 (4) (1983) 305–311]. In rectangular channel, ultrafiltration experiments for turbulent flow conditions are investigated using synthetic juice (a mixture of pectin and sucrose) with a 50 kDa flat sheet polyethersulfone membrane. Furthermore, a parametric study has been carried out to observe the effects of operating conditions such as electric field, feed concentration, cross-flow velocity etc., on the permeate flux. Experimental results show a significant enhancement in permeate flux with the application of a suitable dc electric field. Model predicted results are successfully compared with the experimental data. Effects of d.c. electric field on the variation of permeate flux along the length of the module are also quantified using the model.