Kinetic Study on the Ca(OH)2/CaO Thermochemical Energy Storage System with Potassium Nitrate Doping
Abstract
Thermochemical heat storage is a novel heat storage technology with high heat storage density and capable of large-scale energy storage for a long time. Ca(OH)2 is a low-cost and readily available material with great application prospects, especially in the solar thermal power generation because of the suitable heat storage temperature. In this paper, KNO3 doped Ca(OH)2 was prepared, and it is shown that 10 wt% of KNO3 doping can most effectively reduce the reaction temperature and accelerate the heat storage rate with nearly no loss of heat storage density. Kinetic parameters and governing equations of dehydration process for pure Ca(OH)2 and KNO3 doped Ca(OH)2 were obtained, which lays the foundation for the subsequent design and simulation of heat storage system. The cycling stability of KNO3 doped Ca(OH)2 was also studied.