NH_3-H_2O-LiBr相平衡特性实验研究

Experimental Research on Characteristics of Phase Equilibrium of NH_3-H_2O-LiBr System

采用静态平衡法对NH3-H2O-LiBr三元混合溶液的平衡压力、平衡温度以及气相成分进行实验分析研究.在平衡釜中对该三元混合溶液的压力-温度特性进行了测试,采用气相色谱仪分析其气相成分.实验的测试温度范围从20℃到90℃,压力最高到2MPa,测试用溴化锂质量浓度范围从5%到60%.实验结果表明,与相同浓度下的氨水溶液相比,三元溶液的气液平衡压力降低了30%～50%,并且其气相中的水含量有了大幅度的降低,气相中水蒸气的含量最低达到2.5%.这些结果将对该三元溶液在工业吸收式制冷机以及热泵上的应用提供了依据.

An equilibrium cell was used to measure thermal property of the ternary NH_3-H_2O-LiBr mixtures. New vapor liquid equilibrium(VLE) data were obtained for the ammonia-water-lithium bromide ternary solution at different temperature points from 20 to 90℃,and pressures up to 2 MPa. The salt concentration of the solution was chosen in the range of 5%-60% mass ratio of LiBr in pure water. The VLE for the NH_3-H_2O-LiBr ternary solution was measured statically. The experimental results show that the equilibrium pressures would be reduced by 30%-50%,and the amount of component of water in gas phase would be reduced greatly to 2.5%. The present results would benefit the industrial absorption refrigerator and absorption pump applications of the ternary solution。