Process intensification through magnetic treatment of seawater for production of drinking water by membrane distillation process: A novel approach for commercialization membrane distillation process

In this study, a novel method for intensification of drinking water production from seawater in a membrane distillation system is introduced. For this purpose, the feed water was passed through an intensive magnetic field and then introduced to the membrane module. The experiments were carried out for 80 h at different feed temperatures and flow rates, and different magnetic field intensities to ensure the effectiveness of the method. The best location for applying the magnetic field was determined, experimentally. In the absence of the magnetic field, a flux decline of about 50% was observed during 80 h of operation, while by applying three pairs of magnets, a 20% increase in the permeate flux and 72% decrease in the product TDS was observed. By increasing the magnetic field intensity, the size and the amount of the scale particles formed in the bulk solution increased but the analysis revealed that the scale build-up on the membrane surface was decreased upon applying the magnetic field. The process was optimized by the RSM method for obtaining the operating condition for attaining the best performance of the membrane system. At this optimum condition, an average permeate flux of 3.06 L/ m2.h was obtained.