Effects of Fin Configuration and Structural Parameters on the Exothermic Performance of a CaCO3/CaO Thermochemical Energy Storage Reactor

Thermochemical energy storage technology offers an effective approach to address the intermittency and instability of solar energy supply, thereby enhancing its utilization efficiency and reducing dependence on fossil fuels. The CaCO3/CaO system provides a low-cost, abundant, and safe thermal energy storage solution with high energy density, suitable for large-scale use. However, the low effective thermal conductivity of the storage material in fixed-bed reactors often leads to limited heat transfer performance. To address this issue, this study investigates the internal temperature distribution and reaction field in a finned reactor, with a focus on the effects of fin geometry (including layout, number, and dimensions) on the carbonation reaction performance. The results demonstrate that the incorporation of fins significantly enhances heat transfer within the reactor. Hor-izontal fins increased the reaction rate by 11.81%, while vertical fins resulted in a more pronounced improvement of 41.17%. Furthermore, variations in fin structural parameters markedly influenced the carbonation process. Increasing the number of vertical fins from four to eight improved the reaction rate by 24.23%. Under the conditions studied, the optimal fin configuration, with a thickness of 0.002 m, a length of 0.03 m, and a total of eight fins, achieved the shortest carbonation time. This study provides valuable insights into the design of efficient reactor structures for enhanced thermochemical energy storage.