Experimental Comparison Between Ammonia-Water and Ammonia-Water-Lithium Bromide in Absorption Chiller

Absorption refrigeration experiment was conducted to find the influences of lithium bromide on the performance of an absorption system with ammonia-water working pair,including variation of vapor-liquid equilibrium property and coefficient of performance(COP) of the system.The relationship between temperature and pressure of the ternary ammonia-water-lithium bromide solution in generation process and COP of the system were determined in the range of 15-80 ℃ and up to 1.5 MPa.Three types of solutions,A(X(NH3)=48%),B(X(NH3)=51.8%,X(LiBr)=42%),and C(X(NH3)=58.7%,X(LiBr)=42%),were adopted in the experiment.The results showed that the generation pressure of the solutions B and C decreased by 21% and 30%,respectively,compared with that of the binary solution with the same NH3 concentration.The pressure reduction increased with the increase of the generation temperature.In addition,the COP of the system with B and C was 0.293 and 0.334,17.2% and 33.6% greater than that with A,respectively.