Insights into the effect of physical characteristics of silica gel adsorbents on the performance of adsorption desalination cum cooling processes

Abstract

In this study, the effect of the physical properties of adsorbents (A++, RD2560, NS10) on the performance of an adsorption desalination (AD) system was investigated. The physical properties of the adsorbents and adsorption characteristics of the adsorbents on water vapor were analyzed and compared with adsorption isotherms of nitrogen and water vapor on the adsorbents, respectively. A modified empirical isotherm model was developed based on adsorption isotherms of water vapor on the adsorbent. Mathematical and numerical models were then developed to evaluate the performance of the AD system for different adsorbents, and were validated by comparison with experimental results. The AD performance was evaluated for different types of adsorbents over a wide range of operating conditions such as cycle time, hot- and chilled-water temperatures. The performance was assessed in terms of specific daily water production (SDWP), specific cooling capacity, and performance ratio. Under the given operating conditions, the maximum SDWP of the AD system using A++ was approximately 7.68, which is 5 % and 20 % higher, respectively, than that of RD2560 (approximately 7.29) and NS10 (approximately 6.42). ？ 2019 The Korean Society of Mechanical Engineers.