Abstract

Thermochemical energy storage (TCES) is based on the principle of employing a reversible chemical reaction for thermal energy storage. TCES is characterized by high energy density and low parasitic heat loss while also offering potential functionality as a chemical heat pump (CHP) to boost temperature. Results of experiments conducted on a Ca(OH)2/CaO TCES system based on reversible dehydration-hydration reactions are reported in this paper. Dehydration of Ca(OH)2 pellets conducted in a thermogravimetric-differential calorimetry analyzer (TGA-DSC) revealed that the optimum heating rate ranges from 10-15 K/min for the decomposition of Ca(OH)2. Repeated dehydration-hydration cycles were conducted in a bench scale reactor system under various reaction conditions. It was found that the temperature rise during hydration reaction was dependent on the extent of conversion during the dehydration process. The energy and exergy efficiencies of the dehydration-hydration cycles were found to range from 76% to 79% and 85% to 91%, respectively. Visual and scanning electron microscopic examinations of the product after each reaction revealed structural changes and formation of cracks in the pellets. These changes did not affect the thermal efficiency of the process. Results of this study provide a foundation for the development of Ca(OH)2/CaO CHPs for large-scale thermal energy storage systems.

Full Text
Paper version not known

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 call

Disclaimer: 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.