Advancing Membrane Distillation: Multi-Channel Designs for Enhanced Energy Efficiency and Performance

Membrane Distillation (MD) is a thermally driven desalination process with high rejection rates for non-volatile contaminants. However, traditional single-channel (SC) modules are limited by severe temperature polarization, reducing energy efficiency and overall productivity. This study explores two novel MD module configurations—Multiple Feed Channels (MFC) and Multiple Permeate Channels (MPC)—designed to improve mass and heat transfer, ultimately enhancing system performance and reducing energy consumption. Experiments were conducted using PTFE and PVDF membranes with and without spacers across a feed temperature range of 30°C to 70°C. The MFC and MPC modules demonstrated significant improvements over SC modules, achieving flux enhancements of up to 86% and reducing specific energy consumption (SEC) by up to 63%. Computational fluid dynamics (CFD) simulations validated these findings, revealing improved temperature distribution, reduced polarization effects, and optimized hydrodynamics. These findings highlight the potential of multi-channel MD designs for scalable and energy-efficient desalination and wastewater treatment applications, particularly when coupled with low-grade heat sources.