Mathematical Analysis of Removal of Dissolved Acidic Gases from Aqueous Stream Using Membrane Contactor

Abstract

Abstract-A mathematical analysis was performed on an acid-gas removal process applied to an aqueous feed stream using a hollow fiber membrane contactor in liquid-liquid extraction mode. Furthermore, a comparison was made between the obtained simulation results and with the earlier published experimental results. The model development is based on a process setup wherein synthetic wastewater feed solution was considered to be passing through the lumen side and later recycled back to the feed tank. On the shell side of the membrane contactor, an extractant was circulated in the counter direction. The model is developed considering radial and axial diffusion mechanisms and convection on the lumen side. Mass transfer across the pore by diffusion from Knudsen and bulk flow has also been considered. The partial differential equations obtained, were solved by converting them into a number of ordinary differential equations by using the finite difference method. The model was solved and simulated using MATLAB. The effect of various membrane contactor parameters such as the number of fibers and their effective lengths on the removal of gases have also been studied in this analysis. The simulated results obtained were observed to be in excellent agreement with the experimental results obtained for the acidic gas, H 2 S.Index Terms-Waste water treatment, membrane separation, hollow fiber membrane contactor, degasification of water, modeling and simulation.