Analysis of a pressure driven absorption refrigeration cycle

Abstract

This study presents an analysis of a pressure driven absorption refrigeration cycle which utilizes a membrane separation process to achieve refrigerant-absorbent (R/A) separation. Since the performance of such membranes cannot be predicted generally, the analysis is accomplished by computing cycle performance as a function of the effectiveness of the membrane separation process. The net refrigeration effect and work input are determined based on thermodynamic property data for several working fluid combinations, and desirable characteristics for refrigerant-absorbent pairs are identified. The solubility parameter is used to characterize the potential for separation by candidate membrane materials. The absorbent tetraethylene glycol dimethyl ether (E-181) is found to have good potential for separation from Refrigerants 21 and 22 by typical membranes such as cellulose acetate. The coefficient of performance of the proposed cycle is lower than that of a standard vapour compression cycle operating between the same temperature limits. Improved cycle performance may be achieved by development of a working fluid pair having a more nearly optimum combination of properties.