Decarbonizing industry is crucial to mitigate the impacts of human activities on the environment. Particularly, high-temperature heat (> 250°C) needs are substantial and difficult to decarbonize because of the high amount of energy required. Thermodynamic cycles of Heat Pump (HP), such as Reversed Brayton (RB) cycle, allow for upgrading industrial waste heat to higher temperature usable by processes. However, the energy efficiency of HP to produce heat > 250°C from < 100°C waste heat. Furthermore, an operational AHT prototype allowing for generating heat > 100°C from 80°C waste heat with low energy consumption was developed in our laboratory.

This doctoral thesis offers to study an innovative high-temperature HP combining an AHT with a RB cycle. The concept consists of using the AHT to elevate the temperature level of waste heat to temperature > 100°C and provide it to the RB cycle to generate high-temperature heat > 250°C at a low energy cost. Thus, this hybrid system offers a solution to meet industrial needs in decarbonized high-temperature heat. The main challenges laying ahead are the selection of relevant coupling architectures, as well as the study and development of efficient thermal transfer interfaces.

This research work will require mastering modelling tools of thermodynamic cycles and heat exchangers. The thesis will also involve an experimental aspect, since validation of the numerical results on a laboratory test bench are expected.