Paper No 972 – Numerical evaluation of simultaneous cooling and heating absorption system using H2O/ionic liquid and R32/ionic liquid as working fluids – 14th IEA Heat Pump Conference, Chicago, USA
H2O/LiBr and NH3/H2O are commonly used as working fluids of absorption system in that they present high solubility of refrigerant in absorbent. However, the conventional working fluids need to be substituted considering causticity and toxicity. In this study, a simultaneous cooling and heating absorption system, which is combination of type 1 and type 2 absorption systems, has been analyzed using the numerical methods to improve the coefficient of performance (COP) for heating/cooling applications. The ionic liquid absorbents including imidazole, which has non-causticity and non-toxicity, are utilized as working fluids. H2O and R32 refrigerants are also utilized as working fluids. The thermophysical properties are evaluated by using the nonrandom two liquid (NRTL) model. The variation of COP is analyzed according to split ratio and generation temperature of each component. It is found that the maximum COPtot of H2O/LiBr, H2O/IL, R32/IL are 0.9000, 0.8481–0.9066 and 0.4084, respectively. It is also confirmed that when using H2O/IL, better performance of the absorption system is expected than when using R32/IL, and the crystallization, causticity and toxicity problems are also expected to be solved.