Performance prediction of adsorbent in an adsorption refrigeration system based on variable temperature and constant pressure experiment and dynamic model

Abstract

• A method was designed to predict the performance of MOFs in adsorption refrigeration system using a small amount of MOFs. • The addition of calcium chloride increases the range of suitable cooling conditions for MIL-101(Cr). • The screening time of MOFs in adsorption refrigeration system is shortened. In order to study the performance of metal organic framework materials (MOFs) in adsorption refrigeration systems, the current research method is to test the equilibrium adsorption characteristics of the materials, estimate the adsorption refrigeration conditions of the materials, and then prepare a large amount of them and fill them into the adsorption bed for testing. However, the above methods affect the authenticity evaluation of materials due to the adsorption refrigeration experimental device. In addition, the preparation time of MOFs materials is generally long, and the time cost of verifying materials is high. Therefore, the purpose of this paper is to shorten the prediction time of material performance of adsorption refrigeration system. The large temperature jump method is used to carry out the dynamic adsorption and desorption experiments of three kinds of adsorbents at variable temperature and constant pressure. The dynamic adsorption and desorption model is established and combined with the experimental results to calibrate and verify the combination of heat and mass transfer coefficients of adsorbents. Finally, the performance coefficient of the adsorbent under different conditions is predicted, and the suitable refrigeration operating range is determined. The results show that the addition of calcium chloride increases the range of suitable cooling conditions for MIL-101(Cr). When the desorption temperature is 90°C, the minimum evaporation temperatures of MIL-101 (Cr) and MIL-101 (Cr)/CaCl 2 -20% are 12 °C and 5°C, and the maximum adsorption temperatures are 31 °C and 38°C, respectively.