PH-97-03-1 -- Improving the Performance of Ammonia-Water Absorption Cycles Using Salt Additives and Membranes PDF

Proposes a new design of an ammonia-water absorption refrigeration cycle for low temperature heat sources such as solar energy and waste heat. The proposed cycle uses a salt additive to shift the chemical equilibrium towards more effective separation of ammonia molecules from aqueous solution (ie salting out). Since salt additives can affect all aspects of the absorption cycle, membranes have been chosen to control the flow of ions in the cycle and limit their effects to the generation side. Describes an absorption cycle that use membrane separation processes such as reverse osmosis, dialysis and electrodialysis. Stresses the need for careful choice of the membranes and salts.

KEYWORDS: year 1997, Refrigeration, absorption refrigeration, energy sources, low temperature, ammonia, water, performance, membranes, osmosis