A thorough investigation of thermochemical heat storage system from particle to bed scale
article
Salt hydrates are promising candidates for the long-term thermochemical heat storage (TCES) in thebuilding environment. In such storage systems, the surplus of energy will be exploited in an endothermicreaction to dehydrate the salt hydrates. Once it is demanded, the stored energy will be released throughan exothermic reaction by hydrating the salt, which results in an increase in the mass and temperature ofsalt particles as well as changes in the species of material. In order to construct an improved storage sys-tem, it is very important to deeply investigate the details of the (de)hydration processes in salt hydrates.Poor heat and mass transfer is the bottle neck in this technology. Therefore, the main objective of thiswork is to investigate how heat and mass transfer influence the (de)hydration in a closed TCES-system. The novelty of this work is to provide a high degree of detailed information about (de)hydrationof TCM (thermochemical material) in a bed by calculating transport phenomena for each single particlewhile considering their interactions with each other. This is achieved by applying and developing theExtended Discrete Element Method (XDEM) as a numerical modeling tool and ThermogravimetricAnalysis (TGA) measurements. Comparisons are carried out for the results of the hydration and dehydra-tion process in a single particle with the measurements which shows a very good agreement. Moreover,impact of particle size on the hydration process is also studied. Further, simulations for the hydrationprocess in a chain of six potassium carbonate (K2CO3) particles are performed in order to understandthe mechanism of heat and mass transfer inside the packed beds.
TNO Identifier
957893
ISSN
00092509
Source
Chemical Engineering Science, 246
Publisher
Elsevier
Article nr.
116877