Hybrid concentrator photovoltaic/membrane distillation system for potable water production using new fabricated PS/ZIF_L membrane

Abstract

A hybrid system is proposed to use solar energy as a heating source for the membrane distillation unit. Concentrating photovoltaic needs an efficient cooling system to manage the excess thermal load. Two microchannel heat sinks were proposed to keep the cells from thermal degradation and simultaneously transfer the excess thermal energy to the membrane distillation unit. The results showed a maximum coolant outlet temperature of 59 °C, which is adequate for the membrane distillation unit. A new composite electrospun nanofibrous membrane was successfully synthesized to reduce unfavorable membrane wettability. First, ZIF-L nanoparticles were synthesized and characterized to prove successful preparation, then used as a nanofiller with polystyrene as the polymer membrane matrix for the first time. SEM, XRD, FTIR, static water contact angle, membrane thickness, and porosity were introduced to prove nanofillers' successful preparation and encapsulation. The antiwetting phenomenon was proven by the measured contact angle of 160°. Furthermore, the fabricated membrane was tested experimentally on a lap scale direct contact membrane distillation unit with a productivity of about 4 kg/m2 h and 18 ppm water quality at 55 °C hot water temperature. Also, the introduced membrane outperformed the productivity of the commercial PVDF membrane at all examined operating conditions.