Energy, exergy, economic, and environmental analysis of a high-temperature heat pump steam system.

• A high-temperature heat pump steam system using single-screw compressor that recovers industrial waste heat to produce steam at 170 °C is proposed. • The feasibility and reliability of replacing a coal-fired boiler with a high-temperature heat pump steam system was evaluated using a 4E analysis. • A more advanced economic analysis model is proposed in the 4E analysis, which considers the recovery value of waste heat and CO 2 trading prices. Industrial steam is widely recognized as a valuable form of heat currency, possessing considerable social and economic significance. As the industry shifts to low carbon emissions, there is an urgent need to reduce CO 2 emissions from industrial steam generation. The analysis of a high-temperature heat pump steam system (HTHPSS), which recovers industrial waste heat to produce high-temperature steam at 170 °C, includes evaluations of its energy, exergy, economic, and environmental (4E) to determine whether it can replace a coal-fired boiler. The economic analysis considered the recovery value of waste heat and the effect of CO 2 trading prices. Optimization calculations were performed to investigate changes in the waste heat temperature and condenser outlet temperature. The study also offers recommendations for operational conditions and optimization strategies for the HTHPSS. The results indicate a positive correlation between the system coefficient of performance (COP) and the waste heat utilization rate with waste heat temperature and condenser outlet temperature. The maximum COP value is 2.73. The total exergy efficiency initially increases and then decreases as waste heat temperature increases. It also decreases as the condenser outlet temperature increases, reaching a peak value of 43.26 %. The waste heat temperature needs to be at least 59 °C to generate a net profit, with a corresponding payback period (PBP) of 4.40 years. The minimum PBP is 0.03 years, independent of waste heat temperature. The annual emission reduction increases as waste heat temperature increases and decreases as condenser outlet temperature increases. These results indicate that a HTHPSS could replace a coal-fired boiler and offer guidance for design optimization. [ABSTRACT FROM AUTHOR]