Experimental assessment of an absorption cooling system operating with the ammonia/lithium nitrate mixture

This paper reports the experimental results of a single effect absorption cooling system of 3 kW of nominal cooling capacity operating with ammonia–lithium nitrate solution. The system was designed and built in the Instituto de Energías Renovables of the Universidad Nacional Autónoma de México and can be used for food conservation or air conditioning. The absorber and generator are falling film heat exchangers. The condenser, evaporator and solution heat exchanger are compact plate heat exchangers. The heat was supplied to the generator at temperatures between 85 °C and 105 °C, while the cooling water temperatures to remove the heat produced during the condensation and absorption varied between 18 °C and 36 °C. The results showed that the system can produce up to 2.7 kW of cooling capacity at heating water temperatures of 95 °C and can achieve evaporator temperatures as low as 1 °C. The experimental coefficients of performance varied between 0.45 and 0.70. Because of the developed system do not need a rectifier and reasonable good coefficients of performance were achieved, the developed system seems to be a good alternative to be used for food conservation or air conditioning. •An absorption cooling system was developed using NH3–LiNO3.•The achieved COP (coefficients of performance) are the highest reported for a system using NH3–LiNO3.•Evaporator temperatures as low as 1 °C were achieved.•COP varied between 0.45 and 0.7.•The developed system seems to be a good alternative for food conservation and air conditioning.