A new absorbent.-refrigerant pair suitable for heat pump heating and air-cooled cooling has been developed. Water has been selected as the refrigerant, mainly from the viewpoint. of high cycle efficiency and safety, while a 1:1 mixture of lithium bromide (LiBr) and zinc chloride (ZnCl₂) by weight has been chosen as the absorbent. in view of its higher solubility and affinity for water. Based on thermodynamic analysis with experimental data on properties, the new absorbent solution will give a heating COP of 1.57 and a cooling COP of 1 .00 as gross values of double-effect absorption cycles, including a boiler efficiency of 80%. As a result of an experimental investigation on corrosiveness and corrosion inhibitors, promising equipment materials and inhibitors have been discovered. Prototypical units of 3 .5kw (1-ton) and 35kw (10-ton) have been installed and are undergoing demonstration testing in the laboratory.

Units: SI