Absorption power cycles with various working fluids for exergy-efficient low-temperature waste heat recovery

Abstract

This chapter introduces absorption power cycles (APC) as a perspective option for power production from low-temperature heat. The multicomponent mixture working fluid can provide low exergy destruction in heat exchangers through variable temperature phase change, thus achieve higher efficiency than alternatives such as ORC. Except for commonly known Kalina cycle using NH3-H2O mixture, there is a wide choice of other absorbent-absorbate pairs. This work theoretically explores APC with various types of working fluids compared with ORC (also several configurations and working fluids). Potential of APC is mainly in small systems for low-temperature heat sources around 100 °C regarding both performance and design parameters. It is comparable with the zeotropic ORC, while traditional ORC is the best choice for higher heat source temperatures.