Crystallization Temperature of Aqueous Lithium Bromide Solutions at Low Evaporation Temperature

Abstract

Water- aqueous Lithium Bromide (LiBr) solutions have shown superior performance as working fluid pairs for absorption refrigeration cycles. Most of the available literature (e.g. ASHRAE Handbook of Fundamentals, etc.) provide crystallization behavior down to only 10°C. The typical evaporating temperature for an absorption chiller system is usually lower than 10°C. Hence, it is essential to have an accurate prediction of the crystallization temperature in this range in order to avoid crystallization during the design phase. We have therefore conducted a systematic study to explore the crystallization temperatures of LiBr/Water solutions that fall below an evaporating temperature of 10°C. Our preliminary studies revealed that the rate of cooling of the sample solution influences the crystallization temperature; therefore we have performed a quasi steady test where the sample was cooled gradually by reducing the sample temperature in small steps. Results from this study are reported in this paper and can be used to extend the data available in open literature.