Stabilization of reactive bed particles for thermochemical energy storage with fiber reinforcement
article
Thermochemical energy storage (TCES) is an emerging technology harnessing chemical reactions for storage of
thermal energy. Among the primary challenges for TCES based on crystal-to-crystal chemical transformations is
the design and manufacturing of macroscopic reactive particles that are resistant to mechanical changes over
multiple cycles of operation. Such changes often lead to an increase in the pressure drop over a packed bed,
thereby adversely affecting the performance of TCES. This work explores the effect of polymeric fibers on
reactive TCES particles as a potential route for mechanical stabilization of both the particles and the bed. The salt hydrate K2CO3⋅1.5H2O was used as a model thermochemical material and polyacrylonitrile fibers (PAN) were selected as a reinforcing additive. The stabilization effect of fibers for composite tablets of (K2CO3⋅1.5H2O)#PAN with respect to crushing behavior, salt deliquescence and deformation after 50 cycles was demonstrated and attributed to the shape-stable structures formed by the internal fiber networks. The increase of a pressure drop at a reactive bed of fiber-reinforced particles was found to be smaller by a factor of 1.5–3 as compared to a bed of pure K2CO3 tablets, while the reaction rate was unaffected. Thus, the proposed approach may be an inexpensive and efficient route to stable macroscopic reactive particles for TCES reactors.
thermal energy. Among the primary challenges for TCES based on crystal-to-crystal chemical transformations is
the design and manufacturing of macroscopic reactive particles that are resistant to mechanical changes over
multiple cycles of operation. Such changes often lead to an increase in the pressure drop over a packed bed,
thereby adversely affecting the performance of TCES. This work explores the effect of polymeric fibers on
reactive TCES particles as a potential route for mechanical stabilization of both the particles and the bed. The salt hydrate K2CO3⋅1.5H2O was used as a model thermochemical material and polyacrylonitrile fibers (PAN) were selected as a reinforcing additive. The stabilization effect of fibers for composite tablets of (K2CO3⋅1.5H2O)#PAN with respect to crushing behavior, salt deliquescence and deformation after 50 cycles was demonstrated and attributed to the shape-stable structures formed by the internal fiber networks. The increase of a pressure drop at a reactive bed of fiber-reinforced particles was found to be smaller by a factor of 1.5–3 as compared to a bed of pure K2CO3 tablets, while the reaction rate was unaffected. Thus, the proposed approach may be an inexpensive and efficient route to stable macroscopic reactive particles for TCES reactors.
Topics
TNO Identifier
1006054
Source
Journal of Energy Storage, 101, pp. 1-9.
Article nr.
113764
Pages
1-9