Energy saving in air conditioning systems: study of an innovative passive technique based on membrane contactors and hygroscopic solution

Abstract This paper deals with the application of membrane vapour exchangers operating with LiCl hygroscopic solution in air-conditioning systems. The application investigated achieves enthalpy recovery between the renewal air and the exhaust air by means of an LiCl solution loop incorporated into a traditional air-conditioning plant. The system operates by means of two membranes contactors. The first one acts on the renewal air flow and the second on the discharged air flow. In the present study, summer and winter climatic conditions are considered. In summer conditions, the renewal air, which is warm and humid, is dehumidified and cooled, while the exhaust air, which is cold and dry, can be used to regenerate the solution. The opposite process takes place in winter conditions. The analysis has been carried out by means of a SIMULINK program able to investigate the performances of the device. Results of simulations show considerable energy saving in both summer and winter conditions.