A modified resistance model for simulating baffle arrangement impacts on cross-flow microfiltration performance for oily wastewater

Abstract As a principal problem in the microfiltration processes, cake formation and concentration polarization phenomena cause permeate flux reduction. In the industrial scale, baffle as a turbulence promoter is an efficient method to decrease the fouling phenomenon. In the current study, eleven baffle arrangements in the feed channel were considered for an oily wastewater emulsion. The baffles with four general configurations of wall baffle, central baffle, baffles installed near the membrane surface, and a combination of them are used. The effects of baffle arrangements on turbulent kinetic energy, turbulent dissipation rate, pressure drop, and shear rate, and oil concentration on the membrane surface are examined under steady-state conditions. A modified model of total resistance is proposed to predict the baffle impacts on the CP and cake layer thicknesses and decrease the computational time. The predicted values are compared against experimental data and the absolute relative error is decreased from 6.54 % to 0.03 % by applying the modified resistance model. As the main results, the baffles installed near the membrane surface are more efficient to separate oil from oil-in-water emulsion but it may be caused some problems at higher processing times and the central baffles are recommended for the industrial applications.