This research aims to develop novel binary working pairs using low-GWP refrigerants (R32, R152a, or R161) and one chemical absorbent (DMETEG) for absorption refrigeration systems . The solubility data were determined from 293.15 to 343.15 K using a static method and were correlated with the five-parameter non-random two-liquid (NRTL) activity coefficient model with an average relative absolute error of <2.4%. All three binary mixtures exhibited negative deviations from Raoult’s law. DMETEG was further assessed with other organic solvents that were previously measured to verify its highest affinity with HFCs. Based on the obtained VLE data, the thermodynamic performances in both the single-stage absorption refrigeration system (ARS) and the absorption-compression hybrid refrigeration system (ACHRS) were assessed. R161 yielded the highest cooling COP of 0.519–0.555 when the generation temperature was above 135 °C, followed by the R152a at 0.231–0.518 when below 135 °C. Different from the trends of COP variations, R152a had the highest ECOP of 0.091–0.158 when the generation temperature was below 135 °C while R161 showed the highest ECOP of 0.116–0.137 over 135 °C. ACHRS can effectively enhance the cooling performances of ARS via compression and its compression ratios got optimized. Overall, the R161 + DMETEG showed the best potential as the working pair.
The feasibility of combining novel halogenated hydrocarbon-based working pairs with low-pressure compression-assisted absorption refrigeration system (LCARS) was proved for the first time from the experimental perspective. An experimental prototype of the absorption-compression hybrid refrigeration system with a 1 kW cooling capacity was designed and tested to explore actual performances of selected R134a-DMETEG and performance improvements from compression in LCARS. At an evaporation temperature of approximately 5 °C, as the hot water inlet temperature and the solution flow rate change from 75 to 95 °C and 1.2–2.7 L/min, respectively, the coefficient of performance (COP) in the single-stage absorption refrigeration system (SSARS) varies from 0.211 to 0.412. At an increased evaporation temperature of approximately 10 °C, as the hot water inlet temperature and flow rate increase from 70 to 80 °C and 1.18–2.89 L/min, respectively, the COP in the SSARS varies from 0.238 to 0.552, while the COP in LCARS is improved and varies from 0.470 to 0.617. The LCARS increases the COP by a maximum of 91.04 % and can utilize a lower-grade heat source more efficiently due to its higher optimal COP at reduced hot water inlet temperatures. This study provided one feasible technical approach of combined use of R134a-DMETEG and LCARS to make up for the application limitations of traditional working pairs, contributing to application promotions of absorption systems, especially for the occasions with high requirement on safety and lightweight.
危险品化学品经营许可证（带存储）