Performance evaluation of the electrodialysis regenerator for the lithium bromide solution with high concentration in the liquid desiccant air-conditioning system

In this paper, an electrodialysis regeneration experimental system was set up to evaluate the performance of electrodialysis regeneration system using lithium bromide solution, whose concentration is much higher than that of LiCl solution. The effects of cycling flow rate, initial concentration, and operating current on the current efficiency of the electrodialysis regeneration system using LiBr solution were studied. The current efficiency model and regeneration result model of the electrodialysis regenerator for LiBr solution were acquired based on experimental results. The results show that the ED regenerator can regenerate the LiBr solution reliably, and the current efficiency of the ED regenerator using LiBr solution is lower than that for LiCl solution. To enhance the capability of electrodialysis regenerator, the difference in cycling flow rates between dilute and concentrate chambers should be controlled. The current efficiency of the electrodialysis regenerator and COP of electrodialysis regeneration system decreased with the increase of the operating current and initial concentration. When the concentration of LiBr solution is 45% and the operating current is 3A, the electrodialysis regeneration system has the maximum current efficiency of about 30.365% and the maximum COP of 4.26.