Application of CO2 based power cycles in waste heat recovery
bookPart
Waste heat recovery (WHR) holds promise for reducing fuel consumption and mitigating greenhouse gases. However, numerous obstacles hinder its implementation. Introducing versatile new technologies capable of adapting to various circumstances and modes of operation can help alleviate WHR challenges. CO2 power cycles, offering flexibility and
environmentally friendly options, can be tailored to different situations. This chapter explores CO2 cycles, their application in WHR, and potential barriers to their implementation. Before delving into these sections, let us
provide a brief introduction to thermodynamic cycles. Thermodynamic cycles are broadly classified into two categories, refrigeration and power, as shown in Fig. 5.1 (Tosun, 2020). This chapter is focused on the latter, specifically Rankine and Brayton cycles. Rankine cycle is a sequence of thermodynamic processes that convert heat energy into mechanical energy. It starts by converting water into steam in the boiler, then at a certain pressure and temperature (heat energy), the steam moves the turbine blades (mechanical energy). On the contrary, Brayton cycle uses air as a working fluid. The air enters a combustion chamber (heat energy) to reach certain pressure and temperature (mechanical energy) that allow it to move the turbine blades (Jouhara, 2024). Fig. 5.2 shows the difference between the two cycles schematically and on the temperature– entropy (T–S) diagram.
environmentally friendly options, can be tailored to different situations. This chapter explores CO2 cycles, their application in WHR, and potential barriers to their implementation. Before delving into these sections, let us
provide a brief introduction to thermodynamic cycles. Thermodynamic cycles are broadly classified into two categories, refrigeration and power, as shown in Fig. 5.1 (Tosun, 2020). This chapter is focused on the latter, specifically Rankine and Brayton cycles. Rankine cycle is a sequence of thermodynamic processes that convert heat energy into mechanical energy. It starts by converting water into steam in the boiler, then at a certain pressure and temperature (heat energy), the steam moves the turbine blades (mechanical energy). On the contrary, Brayton cycle uses air as a working fluid. The air enters a combustion chamber (heat energy) to reach certain pressure and temperature (mechanical energy) that allow it to move the turbine blades (Jouhara, 2024). Fig. 5.2 shows the difference between the two cycles schematically and on the temperature– entropy (T–S) diagram.
Topics
TNO Identifier
1023777
Source title
Waste Heat Recovery; It's Utilization and Performance Assessment. Funamentals and Application
Pages
121-151
Files
To receive the publication files, please send an e-mail request to TNO Repository.