The evaluation of working pairs for single absorption cycle based on excess Gibbs free energy
Yibo FANG1, Jiongliang HUANG1, Yuwen ZHOU1, Kangli BAO1, Xiaogang QIAO2, Xiaohong HAN1, Guangming CHEN1.
1Institute of Refrigeration and Cryogenics, Zhejiang University, Hangzhou, People's Republic of China; 2Zhejiang College of Construction, Hangzhou, People's Republic of China
The absorption cycle is one of methods to use the waste heat. There are many series of the absorption working pairs, however, there still is not a defined scale to choose an optimal working pairs for one absorption system. In this work, the published vapor-liquid equilibrium (VLE) data of halohydrocarbon working pairs were collected and tabled. The VLE data were correlated with NRTL model, and the maximum relative pressure deviations were within 5%. The single absorption cycle model was established, and the coefficient of performance (COP), cycle ratio (f), and exergy efficiency (η) were evaluated. The results showed that the working pairs with negative excess Gibbs free energy (GE) had a better system performance, and there was an optimal interval of GE for COP, f, and η. This work attempted to make GE as one of parameters to choose absorption working pairs.
