Study on adsorption equilibrium of adsorbent-refrigerant pairs for adsorption cooling system application

In this study water adsorption onto silica gel arc experimentally measured and isotherm data successfully correlated with Guggenheim-Anderson-dc Boer (GAB) model. The Silica gel/water pair is compared with four different adsorbent-refrigerant pairs from the literature (i.e. KOH activated phenol resin based activated carbon (KOH6-PR)/ethanol pair, activated carbon (Maxsorb III)/methanol pair, zeolite (AQSOA-Z02)/water pair and polymer (PS-II)/water pair. The cooling performance parameters like specific cooling energy (SCE) and coefficient of performance (COP) of ideal adsorption cooling cycle employing each pair are evaluated by using a time independent thermodynamic model. The Duhring (i.e. P-T-W) diagram containing the ideal cycle operative at evaporator and regeneration temperatures of 10 degrees C and 80 degrees C. respectively, is constructed. Also, ideal cycle performances of adsorption system are evaluated for the evaporator temperatures of 5 degrees C and 10 degrees C while having the regeneration temperatures range of 55 degrees C to 80 degrees C. It is found that among the selected adsorbents-refrigerant pairs Maxsorb III /methanol pair has the maximum SCE and COP, at 10 degrees C evaporator temperature, of 898.19 kJ/kg and 0.807 respectively. While minimum SCE and COP is attributed to silica gel/water pair.