Saline Water Desalination Using Direct Contact Membrane Distillation: A Theoretical and Experimental Investigation

Water desalination using membranes is a promising technology and offers a solution to the problem of water scarcity. The present study aims to investigate the experimental and theoretical association between the membrane sheet’s geometric dimensions and freshwater flux. Comparison between experimental and theoretical results shows that the simulation results well agree with the experimental outcomes and the maximum error is less than 1%, indicating that the proposed model is reliable and valid. The Polytetrafluoroethylene (PTFE) membranes employed had a nominal pore size of 0.45 µm and were supported by a scrim layer. With the same velocity, the basic model projected the flow at varied temperatures and membrane lengths (5–15 cm). The modeling outputs were verified against the experimental data, and the errors varied between < 1% at different temperatures and < 5% at different membrane lengths. Direct contact membrane distillation (DCMD) in parallel flow was studied. Also, the research revealed that shorter membrane modules had more outflow versus longer membrane modules under the same conditions. As a consequence, since the outflow from the membrane distillation process is associated with membrane size and temperature, evaluating membrane performance by flux for membrane distillation can only be done under standard conditions and geometries. Furthermore, because it is independent of temperature and membrane module size, the overall mass transfer coefficient provides a superior statistic for measuring membrane performance.