Abstract
In most steelmaking processes, huge amounts of waste heat at high temperature (700–800 °C) are thrown into the environment without any use. An alternative use for this waste heat is electricity generation through thermoelectric generators. However, these high temperatures, as well as their fluctuations over time, affect not only the conversion rate of the thermoelectric generator but also its useful lifetime. The incorporation of a latent thermal energy storage (TES) system could be a solution; nevertheless, the thermal stability and corrosive effect of the (PCM) phase change material are key aspects for the thermal storage system definition, in terms of durability. In this work, developed in the framework of the European project “PowGETEG” (RFSR-CT-2015-00028, funded by the Research Fund for Coal and Steel), a high-temperature analysis (700–800 °C) of the Li2CO3 thermal properties, thermal stability and corrosive effect on the AISI 304 and AISI 310 stainless steels is carried out. The results show that the eutectic salt Li2CO3 exhibits high thermal stability with neither change in its thermal properties nor material degradation. This work shows that lithium carbonate Li2CO3 and AISI 310 make a very good combination for the definition of a thermal storage system able to protect a high-temperature thermoelectric converter from temperature variations, making it more reliable.
Highlights
Thermoelectric energy conversion can be used to capture electric power from waste heat in a variety of applications
Thermoelectric converter life can be assured by incorporating any high-temperature preventive measurement, while efficiency can be achieved by reducing temperature variation
To protect the high-temperature (700–800 ◦ C) thermoelectric converter from the temperature fluctuations, a thermal absorbent based on phase change materials (PCM) is needed
Summary
Thermoelectric energy conversion can be used to capture electric power from waste heat in a variety of applications. Temperature fluctuations can affect very much the conversion efficiency and converter life (thermoelectric semiconductors overheat at high temperature). Thermoelectric converter life can be assured by incorporating any high-temperature preventive measurement, while efficiency can be achieved by reducing temperature variation. Latent heat storage by use of phase change materials (PCM) appears as an appropriate technology to absorb temperature fluctuations, that way assuring thermoelectric converter life and efficiency. During a phase change process (melting and crystallization), the PCM material absorbs or releases heat, maintaining its temperature as constant. These phase change phenomena appear in a temperature–time diagram as a plateau
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
