Experimental and theoretical investigation of a new air gap membrane distillation module with a corrugated feed channel

In this study, a novel feed channel was designed and examined for an air gap membrane distillation (AGMD) module to create different geometries, aiming to improve the module's performance. The experimental study has been conducted to investigate the influence of two new feed channels on the enhancement of the membrane sheet thermal boundary. Two feed channel-based designs with different geometries, namely, spacer and corrugated, were examined and benchmarked against the original module. Based on the results, the corrugated feed channel considerably enhanced both the permeate flux and the gain output ratio (GOR) compared with the spacer feed channel under the same operating conditions. The results also showed that the maximum enhancements of the permeate flux and GOR of the corrugated surface and spacer feed channel modules were 50% and 20% and were 40% and 10%, respectively, compared with the original module. The temperature polarization coefficients (TPC) for the corrugated feed channel module were near unity. According to the current study, the maximum performance of the proposed module occurred at the higher studied temperature of 80 °C, which consequently proved that the novel feed channel is more effective than the original one. •An AGMD module equipped with various newly feed channel geometries experimentally investigated.•The proposed newly feed channel geometries are corrugated surface and spacer.•The permeate flux for corrugated surface module is improved by 50% at high feed solution temperature.•The maximum enhancement of permeate flux occurred with corrugated surface at the temperature of 80 °C.•The GOR of the corrugated surface module is 40% higher than the original module.