Insight to evolution of particle size and penetration resistance of Ca(OH)2/CaO powder bed for thermochemical energy storage

During the Ca(OH)2/CaO thermochemical energy storage process, the cyclability of reactions and the consolidation properties of powder storage are important issues to consider. In this study, experiments were conducted to assess the evolution of reaction conversion, particle size and penetration resistance of Ca(OH)2/CaO powder fixed bed. The results revealed that the final conversions of both the hydration and dehydration reactions stabilized between 70 and 80%. The particle size distributions of Ca(OH)2 increased initially and then decreased with the increasing cycle number and degree of dehydration. The dehydration conversion was the dominant factor for changing Ca(OH)2 bed penetration resistance force. The particle size and penetration resistance of the CaO bed remained stable during long-term storage at high temperatures. The theoretical analysis of the inter-particle forces agreed with the trend of the experimental results, with particle size and moisture content being the main factors affecting cohesion.