Effect of regulating main governing factors on the selectivity membranes of electrodialysis used for LiCl liquid desiccant regeneration

Abstract

This paper experimentally investigated how temperatures of the regenerated solution and spent solution together with other key governing factors influence the performance of electrodialysis (ED) used for liquid desiccant regeneration. A matrix of experiments based on Taguchi Orthogonal Arrays was designed and performed using a lab-scale ED system. Three different scenarios were designed to investigate the effect of solution temperature on the concentration increase and power consumption of the ED regeneration. The experimental design and data analysis were performed using Taguchi method and Analysis of Variance, respectively. The results showed that the highest improvement in concentration increase of the solution through the regenerated channels was around 19% and the highest saving in the power consumption was 19.3%, when the temperatures of the solutions at the inlet of the spent channels and regenerated channels were elevated from 30 to 45 °C and from 20 to 30 °C respectively, while maintaining the other parameters unchanged. The results obtained from this study could be used to guide the operation of the ED stack for liquid desiccant regeneration.