Analysis of an absorption/absorption–compression refrigeration system for heat sources with large temperature change

Abstract

Absorption refrigeration systems are a promising way to reduce electricity consumption in the field of refrigeration and cooling. To improve the thermal energy utilization performance of the absorption refrigeration system, an absorption/absorption–compression refrigeration system with a large working range is proposed in this paper. The new system consists of a conventional single-effect absorption subcycle and an absorption–compression refrigeration subcycle, and they share the condenser, evaporator, absorber and some other relative components. The temperature of the waste gas exhausted from the system can be 35°C lower than that of the waste gas from a traditional, single-effect absorption refrigeration system. For the proposed system, the cooling capacity per unit mass of flue gas reaches 58.95kJkg−1 when the evaporation temperature is −15°C, which is 28.21% higher than that of the single-effect absorption refrigeration system. The exergy efficiency of the proposed system is as high as 25.94%. To indicate the direction of system optimization, the new system is further studied using a parametric analysis. The new absorption/absorption–compression refrigeration system provides a promising way to efficiently utilize heat sources with large temperature change or multiple heat sources with different temperatures.