Working domains of a hybrid absorption-compression heat pump for industrial applications

• Published in: Energy conversion and management 2019-09, Vol.195, p.226-235
• Main Authors: Liu, Changchun, Wang, Zefeng, Han, Wei, Kang, Qilan, Liu, Meng
• Format: Article
• Language: English
• Subjects: Absorption; ACHP; Air temperature; Ammonia; CHP; Cogeneration; Compression; Domains; Heat; Heat exchangers; Heat pumps; High temperature; Hot water heating; Hybrid systems; Industrial applications; Industrial heat pumps; Internal combustion engines; Mixture working fluid; Power consumption; Steam electric power generation; Steam production; Temperature effects; Waste heat
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2019.05.013

•The working domains of a hybrid heat pump for saturated steam is revealed.•The optimized performance of the hybrid system at different conditions is obtained.•A new evaluation criteria is defined to evaluate the hybrid heat pump system.•Comparison study with a typical heat pump system with/without rectifier is presented.•The application of the hybrid heat pump system is promoted. Absorption-compression heat pumps are especially suitable for high-temperature heat production, however, its performance at different conditions are highly influenced by the choice of ammonia-rich solution mass fraction and circulation ratio. This paper revealed the working domains of a hybrid absorption-compression heat pump for high-temperature (>130 °C) saturated steam production and obtained its optimized thermodynamic performance at different conditions. For saturated steam production, a supplied heat temperature up to 160 °C can be obtained using commercially available components with a thermal benefit compared to a gas boiler. For hot water or air production, the supplied temperature can be even higher. Moreover, a new heat coefficient of performance is proposed to evaluate the heat pump systems with both heat and power consumption. There are optimal heat coefficient of performance values for the circulation ratio and ammonia-rich solution mass fraction for the hybrid system. The results indicated that setting the ammonia-rich solution mass fraction less than 0.6 and the circulation ratio more than 0.7 is a better choice for the hybrid system in actual application. Finally, the hybrid heat pump system was used to improve the thermal performance of a saturated steam and power cogeneration system driven by an internal combustion engine. This work provides a useful guidance for the hybrid absorption-compression heat pump in actual application.