Thermochemical Resorption Heat Pump Module: A Case Study with the UK Climate

Resorption systems (RES) utilize the difference in ammonia equilibrium between two distinct salts to produce useful heating/cooling. The salt with comparatively lower ammonia affinity is used as a Low-Temperature Salt (LTS), while the other is used as a High-Temperature Salt (HTS), in a two-reactor system. In this work, BaCl2, MgCl2, NaBr, NH4Cl and SrCl2 are paired with 18 different HTSs, and each pair is studied and thermodynamically mapped for high/low operating temperatures, pressures, COP and energy output. NH4Cl and NaBr are found to be promising LTSs, while SrBr2 and MnSO4 are found to be more suited as HTSs. The resulting four combinations can be used for residential heating in the United Kingdom. The thermodynamic cycle evaluations suggest that the COP range lies between 1.10 and 1.50. In addition, more than 4140 J gNH3−1 of heat energy can be delivered using these pairs for residential heating at 50 °C.