Numerical model as a tool for the optimisation of performance of a TEG generator for recovering waste heat from process gas

Abstract The article focuses on the issue of efficiently recovering waste heat from low-exergy process gases, which poses a significant challenge for improving energy efficiency in many industrial sectors. To address this problem, the application of a thermoelectric generator (TEG) has been proposed, allowing for the direct conversion of thermal energy into electrical energy. In the course of the research, experimental measurements were conducted for process gases at temperatures of 240 °C and 300 °C, along with CFD (computational fluid dynamics) simulations using Ansys Fluent 2023 R2 software. These simulations enabled the analysis of the temperature distribution in the TEG and the determination of the safe operating range of the device for process gas temperatures of 350 °C, 400 °C and 450 °C. The results obtained from both experiments and simulations demonstrated the effectiveness of the TEG in recovering waste heat from low-exergy gases. Additionally, these findings suggest the potential for scaling the solution to larger industrial systems, making TEG a promising technology for long-term sustainable development efforts. The developed numerical model proved to be a valuable tool in the design of TEG systems, allowing for the analysis and optimization of heat recovery systems. The innovation of the solution lies in the use of TEG for efficiently utilising waste heat from low-temperature gases, which holds significant potential for improving energy efficiency in processes where traditional energy recovery technologies are not effective.