Mesurages de l'équilibre vapeur-liquide et évaluation des performances thermodynamiques de paires de frigorigènes écologiques R1270+DMETrEG et R1270+NMP pour un système frigorifique par absorption.

As an environmentally sustainable refrigeration technology, the absorption refrigeration cycle (ARC) has garnered increasing attention, and research on the vapor–liquid equilibrium (VLE) of novel working pairs is of great significance for the promotion and development of ARC. This article innovatively measured the VLE of hydrocarbon (HC) refrigerant R1270 in organic solvents DMETrEG and NMP in the temperature range of 303.15 K to 353.15 K, and used the non-random two-liquid (NRTL) model to fit the experimental data and evaluate their performance in the ARC. For the R1270+DMETrEG, the average absolute relative deviation (AARD) and maximum absolute relative deviation (MARD) are 0.8318 % and 2.8169 %, respectively. For the R1270+NMP, the corresponding values are 1.4472 % and 3.1676 %. In the thermodynamic analysis of the ARC, the maximum coefficient of performance (COP) of the R1270+DMETrEG working pair is 0.327, which is higher than 0.313 of the R1270+NMP. Compared to COP values predicted using a UNIFAC-DMD model, the COP calculated from experimental VLE data is approximately 0.02–0.08 lower, although the overall trend remains consistent. In all cases, the COP of R1270+DMETrEG is higher than that of R1270+NMP, in both experimental and predicted results. Based on the experimental data, the COP of the R1270 working pairs is 0.01–0.1 lower than that of R1234yf and R1234ze(E). At constant generation temperature, both working pairs exhibit similar COP trends as a function of evaporation and condensation temperatures. Analysis of excess properties shows that the excess Gibbs energy (GE) is negatively correlated with refrigerant solubility and COP.