基于钙镁二元盐的热化学储能反应器的性能优化

Thermochemical energy storage material of salt hydrate has high energy storage density, and the regeneration temperature is consistent with the temperature of solar collectors. It can be used to improve the utilization of solar energy. The optimization of thermochemical energy storage reactor based on salt hydrate is important for the thermal energy storage system. In this study, a two-dimensional numerical model of the packed bed reactor of Wakkanai Siliceous Shale (WSS) + MgCl₂/2CaCl₂ was established. The effects of the content of calcium and magnesium binary salt hydrate, particle size and the height of packed bed on the heat release process of packed bed were analyzed. The numerical simulation results showed that the outlet air temperature increased with the decrease of the particle size. The decay rate of the outlet air temperature decreased with the increase of the calcium-magnesium binary salt content, increased with the decrease of the particle size and decreased with incresing height of the packed bed. The large salt hydrate content and small particle size were conducive to get high heating power and energy storage density of the packed bed. When the height of the packed bed prolonged, the heat release power increased, while the energy storage density decreased. When the particle size of WSS20 was 2mm, the height of the packed bed reactor was 10cm, the energy storage density can reach 0.985GJ/m³, which was almost 4 times that of water.