Experimental Study on Vacuum Membrane Distillation Liquid Regeneration of Liquid Desiccant Air Conditioning System

LiCl solution was used as the liquid desiccant for the vacuum membrane distillation (VMD) regeneration process of liquid desiccant air conditioning system. The effects of liquid temperature, concentration, length and number of membrane on water flux, mass transfer coefficient, interception and regeneration were studied. The results show that the temperature of the liquid has large influence on the regeneration performance of VMD, the regeneration capacity increases from 0.1% to 0.8%∼1.2%, and the water flux and mass transfer coefficient also increase with the regeneration temperature. Under the same regeneration capacity, the regeneration temperature of 30% LiCl solution is about 7℃ higher than that of 20% LiCl solution. In order to improve the regeneration effect of high concentration solution, the regeneration temperature can be increased appropriately. In addition, the water flux and regeneration capacity of the solution first decreased and then increased with the increase of the number of membranes. Therefore, the reasonable selection of the number of fiber membrane can significantly save material, but also can improve the regeneration capacity. © 2020, Science Press. All right reserved.