Exergy analysis and performance enhancement ofisopropanol-acetone-hydrogen chemical heat pump

Abstract

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

Key words： waste heat reuse; chemicalheat pump; exergy analysis; isopropanol

Acknowledgment

This work was supported by the NationalKey R&D Program of China (2016YFB0601200) and the National NaturalScience Foundation of China (Grant Nos. 51476173, 51576194).

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