Improving the performance of solar powered membrane distillation systems using the thermal energy storage mediums and the evaporative cooler

The present experimental work aims to improve the performance of solar-powered tubular direct contact membrane distillation (TDCMD) systems. To investigate this idea, the membrane distillation system was integrated with thermal energy storage mediums and the evaporative cooler. The novelty of the present configuration is addition the energy storage mediums (phase change materials PCM) which represent the energy source to extend the water production time after sunset with high rates, as well as, improve the productivity in the period of low solar intensity before sunset. To obtain the influences of PCM on the performance of solar-assisted TDCMD with an evaporative cooler, the present configuration was tested first without PCM and again with utilizing the PCM within different test days under Egyptian climatic conditions. The experimental results show that as increases the rate of feed saltwater from 12 to 16 l/min, the accumulated productivity of solar-assisted TDCMD with evaporative cooler varying between 28.9 and 35.67 l/day while additional the PCM augments the productivity to 41.38–47.48 l/day, representing 33.11–43.18% enhancement in the productivity. Also, the gain output ratio of solar-assisted TDCMD with evaporative cooler varying between 0.77 and 0.93 while additional the PCM augments the gain output ratio to 1.123–1.25, representing 34.4–45.84% enhancement in the gain output ratio.