Heat and mass transfer in LiNO 3-NH 3 spray absorption system

Abstract

In the present work the spray absorption method is studied for the absorption of ammonia refrigerant vapour by lithium nitrate ammonia solutions. Heat and mass transfer coefficients attainable using the spray absorption method are estimated. In this study the low-pressure absorber of a double-stage absorption refrigeration system is considered. The results show that a mass transfer coefficient equal to k m = 18.6.10 -5 m/s may be attained. The heat transfer coefficient (5.8 kW/m 2 K) obtained in the heat exchanger using the spray absorption method and the lithium nitrate ammonia solution is one order of magnitude higher than those obtained using falling film absorbers. This would lead to significantly smaller heat exchanger areas in absorption chillers.