Title
K2CO3 in closed heat storage systems
Author
Houben, J.
Sögütoglu, L.C.
Donkers, P.
Huinink, H.
Adan, O.C.G.
Publication year
2020
Abstract
Potassium carbonate, K2CO3, has been identified as one of the most promising thermochemical storagematerials for the built environment. Where a lot of knowledge has been gained on hydration/dehydrationbehavior at atmospheric (open system) conditions, little is known of this process under pure water vaporconditions (closed vacuum system). In this paper, for thefirst time, the equilibrium behavior and reactionkinetics of a K2CO3composite are investigated under pure water vapor conditions, as present in closedvacuum systems. In this work the metastable behavior of a K2CO3composite is investigated undervacuum conditions and compared to its metastable behavior under atmospheric conditions. It is foundthat the metastable zone is also present in vacuum conditions, however induction times in the meta-stable zone are much shorter which indicates a faster nucleation rate in vacuum conditions.Moreover the effect of inert gasses in a closed system is studied and it is shown that it is critical toremove all sources of non-condensable gasses. Finally in cyclic measurements it is shown that K2CO3isstable in multi cyclic experiments, concluding that it is a suitable material for a heat battery based on theconcept of a closed reactor.
Subject
Potassium carbonate
Thermochemical material
Metastable zone
Closed vacuum system
Non-condensable gasses
Industrial Innovation
To reference this document use:
http://resolver.tudelft.nl/uuid:3286fbde-727d-4ad6-b209-108ca8c91c47
DOI
https://doi.org/10.1016/j.renene.2020.11.119
TNO identifier
884916
Publisher
Elsevier Ltd
ISSN
0960-1481
Source
Renewable Energy, 166 (166), 35-44
Document type
article