Performance evaluations of LiCl and LiBr for absorber design applications in the open-cycle absorption refrigeration system

Both LiCl and LiBr solutions were considered for potential use in a solar-driven Open-Cycle Absorption Refrigeration (OCAR) system. A vertical falling film absorber was proposed and built to evaluate the performance of LiCl and LiBr as an absorbent. Absorption experiments were performed and the results are reported for typical operating conditions of nonabsorbable concentrations, solution concentration, solution temperature, cooling water temperature, absorber pressure, and solution flow rate, in terms of mass transfer rate. In general, LiBr outperformed LiCl in terms of effective absorption rate. Based upon experimental results, the required absorber area was estimated for both LiCl and LiBr. The small chemical potential of LiCl relative to LiBr lends to a larger absorber area. The cost for the required solution storage for three-ton cooling capacity of the present OCAR system was found to be high for both LiCl and LiBr. The pumping cost was estimated to be less than 0.1 kW for both.