Exergy loss analysis was conducted to identify the irreversibility in each component of the isopropanol-acetone-hydrogen chemical heat pump (IAH-CHP). The results indicate that the highest irreversibility on a system basis occurs in the distillation column. Moreover, the effect of operating parameters on thermodynamic performances of the IAH-CHP was studied and the optimal conditions were obtained. Finally, the potential methods to reduce the irreversibility of the IAH-CHP system were investigated. It is found that reactive distillation is a promising alternative. The enthalpy and exergy efficiency of the IAH-CHP with reactive distillation increases by 24.1% and 23.2%, respectively. 

Conclusions:

The highest irreversibility on a system basis occurs in the distillation column, which accounts for about 75%–85% of the total exergy loss. The optimal thermodynamic performances of the IAHCHP system could be obtained at Pdis = 0.12 MPa, Pexo = 0.12 MPa, Tin,reac = 473 K, Tin,cool = 443 K, and xiso,1 = 0.03. Reactive distillation is an effective method to enhance the performances of the IAH-CHP system. The COP and exergy efficiency of the IAH-CHP with reactive distillation part increases by 24.1% and 23.2%, respectively.

The results have been published on Front. Energy 2017, 11(4): 510–515.