Numerical Analysis of Transmembrane Pressure Changes in UF Systems by Changing the Geometry of the Inner Surface of Hollow Fibers

Membrane processes are one of the most important separation methods in water and wastewater treatment processes. Hollow fiber membranes are used in many separation processes due to their high surface area to volume ratio. Since porosity and permeability of porous media depend on its geometric features, a change in the geometry leads to changes in these value and the performance of the system. In this study, a mathematical modeling was made for three fiber geometry categories; including circular, square and elliptical and the geometric features were calculated based on three strategies. In order to investigate the effect of geometry, a double porosity media was considered. Results showed that the ratio of surface area to volume of hollow fiber membranes and the axial permeability in square and elliptic geometries are usually higher than circular fibers and are increased to a maximum value of 27% and 63%, respectively. Also, in a strategy, equivalence of the radius of the inspirational circle of the new geometry with the inner radius of ordinary fibers was less than the circular fiber, which was a desired result and caused a decrease in energy consumption and operation cost of the system