Performance analysis of a fully open absorption heat pump for flue gas waste heat, water recovery, and wet plume elimination

The fully open absorption heat pump (FOAHP) emerges as an innovative technology capable of simultaneously recovering waste heat and water from flue gas while simultaneously eliminating wet plumes. However, given the novelty of the system, detailed theoretical studies investigating the effects of various parameters on both thermodynamic performance and environmental impacts are scarce. To address this issue, this study develops a physical model of the FOAHP, accompanied by the formulation of multidimensional evaluation indices, including the coefficient of performance (COP), dew point temperature, water recovery rate, recovery efficiency, initial cost and life cycle benefit. Simulations using the control variable method are conducted to investigate the effects of various parameters on system performance. Building on the mechanism of wet plume formation, the environmental sustainability of the system is also evaluated. Finally, an economic comparison with conventional AHPs is performed. The results indicate that the COP of the FOAHP reaches up to 1.670 and recovery efficiency reaches up to 85.38 %. Compared to the AHP, the initial cost of the FOAHP is only 334.41 CNY/kW, representing a cost saving of approximately 44.27 %. Additionally, the FOAHP effectively addresses the issue of wet plume formation caused by the direct discharge of low-temperature, high-humidity flue gas.