A wavy flow channel system for membrane fouling control in oil/water emulsion filtration

Abstract

The membrane-based process is attractive for the treatment of oil/water emulsion because of its effectiveness in handling micron size oil droplets. However, membrane fouling due to the strong oil droplets/membrane surface interplay remains its major challenge that limits its widespread application. This study reports a new approach for membrane fouling control via a wavy flow channel to enhance the effective area and improve the local mixing. The hydraulic performance of a membrane was used to assess the effectiveness of the system against the traditional straight flow for oil/water emulsion treatment. Results show that the wavy flow channel offers two main advantages: increasing the membrane effective surface area and facilitate swirling flows that effectively promote fouling control. The wavy flow channel showed up to ~58% higher permeability (of 219.1 ± 5.8 L.m−2.hr−1.bar−1) than the reference, in which 18% was due to the enhanced flow property. The energy loss due to additional shear stress and longer flow path only contributed to a 7% additional pressure drop. The energy to overcome the pressure drop was insignificant to the specific energy consumption, which showed that the wavy membrane offered 21% energy saving (0.015 vs 0.019 kWh/m3). This study opens an option in improving membrane filtration performances via a simple module-scale modification suitable for fouling prone pressure-driven membrane systems.