Numerical investigation of multiple channels module for enhanced water production in membrane distillation

Abstract

This paper introduces a novel numerical model for investigating the Multiple Channels Direct Contact Membrane Distillation (MCDCMD) process, which features multiple feed and permeate channels separated by membranes. We compare the performance of this new module with that of a conventional module under various operating conditions. The CFD model has been validated against experimental productivity data obtained from the conventional module and also compared with the MCDCMD module. Our findings reveal that the new MCDCMD module significantly improves productivity by 100 % across all tested conditions, as compared to the conventional DCMD laboratory setup. Additionally, employing a feed channel with a thickness of 0.5 mm leads to a 10 % improvement in productivity over the baseline module with a 1 mm thickness, owing to the substantial temperature variance between membrane surfaces. Turbulence intensity further boosts the productivity of pure water, with a 37 % increase observed at a lower velocity of 4.17 cm/s and a 27 % increase at a higher velocity of 68 cm/s. Overall, the proposed MCDCMD module exhibits a remarkable 137 % improvement in productivity relative to the conventional module. Finally, the experiments are performed with the new design of MCDCMD and verified with the CFD model. Our findings suggest that the proposed MCDCMD module could significantly advance the development of an industrial-scale, energy-efficient DCMD process, particularly for producing high-quality water with improved productivity. Future studies may propose various design modifications aimed at achieving an optimized configuration of commercial-scale DCMD technology.