Preparation of Macro Encapsulated Phase Change Materials for High Temperature Energy Storage Applications

摘要

Capsulated phase change materials (CPCM) is one of the most interesting and applicable high energy density solutions due to the store of thermal energy, though there has been little investigations for such systems at high temperature (Jamekhorshid et al. in Renew Sustain Energy Rev 31:531-542, 2014 [1], Qian et al. in Energy Convers Manag 98:34-45, 2015 [2]). The aim of this work is to create a CPCM with high durability for high temperature applications. The capsulation can be made by physical or chemical methods (Qian et al. in Powder Technol 282:37-42, 2015 [3]). Phase change materials (PCMs) are substances which melt and solidify at a constant temperature and are capable of storing and releasing large amounts of energy when undergoes phase change (Gimenez Gavarrell and Fereres, Renew Energy 107:497-507, 2017 [4]). NaNO_3 served as a phase change material (PCM) in this work for thermal energy storage, while diatomite acted as the carrier matrix to provide the structural strength and prevent the leakage of PCM. The fabrication process involved weighing the two particulate materials, followed by grinding them separately at the ambient temperature. The tableting was done resulting pellets were 15 mm in diameter and 5 mm thickness. After sintering, the pellet infrared camera was used to identify the temperature of the PCM in the period of time and the time of high temperature stabilization that can be used in high temperature applications such as solar concentrated panels (Deng et al. in J Mater Sci Technol 33(2): 198-203, 2017 [5]).