| Abstract: | Recent research has been focused on the utilization of low‐grade waste heat, and the industrial high‐temperature heat pump can be an alternative technology because of its simplicity and outstanding performance. However, the use of carbon dioxide in vapor compression heat pumps with high‐temperature heat source is still to be optimized because of low critical temperature. In the present study, a system for waste heat recovery from the steam condenser using CO2 vapor compression cycle is modeled from the energetic, exergetic, and economic perspectives, and optimized system performances are obtained by dual‐objective Jaya algorithm. Potential optimized operating strategies for transcritical cycle are discussed by the parametric study and T‐s diagrams. The transcritical and supercritical cycles are further compared with each other considering different steam temperatures. The optimization strategies of transcritical cycle are based on the main purpose to improve the evaporation potential and achieve transcritical cycles with the critical point inside the closed region surrounded by the process curves, so lower superheating degree and minimum temperature difference of gas cooler, higher evaporating temperature, and more return water cooling should be employed in order to promote the cycle performances. In comparison with transcritical cycles performances, the supercritical operation shows superior performances, which are less sensitive to the variations of return water temperature. |
