Method for preventing loss of molten salt phase-change heat storage material by utilizing activated carbon

[0003] Molten salt phase change materials have high heat storage density and low cost, and are a hotspot in the field of energy storage materials. However, there are still many problems in the heat storage system of molten salt as a phase change heat storage material. Loss, insufficient mechanical properties of heat storage body, etc.

These problems have seriously affected the application cycle and range of use of the heat storage body, and urgently need to be resolved

[0004] Researchers at home and abroad mainly adopt the method of overall encapsulation to solve this problem. Ryo Fukahori (Fukahori R, Nomura T, Zhu C, Sheng N, Okinaka N, Akiyama T. [J].Appl Energy 2016; 170:324-8) Ceramic cups are used to encapsulate the molten salt, and the molten salt is placed in the ceramic cup body and sealed on the outer layer. This method can isolate the humidity environment and provide a supporting structure. The cup The space of the body can leave an expansion space for the molten salt to solve the problem of the large expansion coefficient of the molten salt, but this method is cumbersome to prepare and the cost is high; the bonding between the ceramic cup and the cup cover will appear to fall off and age as the number of cycles increases phenomenon; Pau Gimenez (Gimenez P, Fereres S. Glass encapsulated phase change materials for high temperature thermal energy storage [J]. Renewable Energy, 2017, 107: 497-507.) adopted NaNO 3 Inject glass spheres to play the role of encapsulation and support. Although this method can completely solve the problem of hygroscopicity of molten salt in an integrated way and provide a support structure at room temperature, the process is difficult, and at high temperatures, the glass will soften. phenomenon, and the softened glass cannot bear the weight of the molten salt, which leads to the leakage of the molten salt from the bottom, which not only fails to play a structural support role, but also makes the entire material invalid; TEAP and EPS Ltd (Pendyala S.Macroencapsulation of Phase Change Materials for Thermal Energy Storage [J]. Dissertations&Theses-Gradworks, 2012.) Using polymer and metal materials to encapsulate the molten salt into the ball body can isolate the molten salt from the external humidity environment and provide a stable structural shape, but this This method not only increases the preparation cost and complicates the process, but also the lower service temperature range of the polymer and the high conductivity of the metal material severely limit the application environment of electric heating; Bhardwaj (Bhardwaj A.Metallic Encapsulation for High Temperature (>500 ℃) Thermal Energy Storage Applications[J].2015.) Carbon steel and nicke