Development of artificial shape-setting energy storage phosphorous building gypsum aggregate

Abstract

The research and development of new building materials such as phosphorous building gypsum is crucial to promote the utilisation of phosphogypsum resources by improving their value. This study developed a new type of shape-stabilised energy storage phosphorus building gypsum aggregate (ES-PBGA). The mechanical and thermal properties of ES-PBGA with Paraffin were investigated. The results indicate that the matrix of ES-PBGA had a good microstructure, and the optimal paraffin-embedding rate of ES-PBGA was 31.08%. The phase transition temperature and enthalpy of the endothermic and exothermic stages were 17.6 and 27.14 ℃, and 33.02 and 31.62 J/g, respectively. The cylinder pressure strength of ES-PBGA with paraffin (31.08%) was 4.32 MPa, which meets the requirements of artificial aggregate application. To verify the practicability of ES-PBGA, energy storage lightweight aggregate concrete was prepared with 0%, 25%, 50%, and 100% ES-PBGA to replace the lightweight shale ceramsite. The results show that ES-PBGA can improve the interface transition zone between cement-based materials and energy storage aggregates, thereby improving the strength, and has a relatively suitable thermal conductivity, thermal diffusion coefficient, and specific heat capacity. Furthermore, it is also a type of low-carbon energy storage aggregate, and its application in the field of energy storage composite building materials is a relatively new concept.

Keywords

• Energy storage
• Phosphorous building gypsum aggregate
• Thermal performance
• Mechanical properties
• Interface transition zone