TITLE:
Dehydration of Gypsum Rock by Solar Energy: Preliminary Study
AUTHORS:
Aurora López-Delgado, Sol López-Andrés, Isabel Padilla, Marta Alvarez, Roberto Galindo, Alfonso José Vázquez
KEYWORDS:
Gypsum, Bassanite, Anhydrite, Concentrated Solar Energy, Fresnel Lens
JOURNAL NAME:
Geomaterials,
Vol.4 No.3,
July
7,
2014
ABSTRACT:
The dehydration
process of gypsum rock was studied under concentrated solar energy by using a
Fresnel lens with power density of 260 Wcm-2. Temperatures higher than 700。C were attained for 1
min of solar exposure. The effect of grain size of sample and radiation
exposure time on the formation of bassanite and anhydrite was studied by XRD. The
complete transformation of dihydrate into hemihydrate and/or anhydrate phases
is complete for the finer size sample. Plaster composed of 92.7% of anhydrite
and 7.3% of bassanite was obtained for 5 min of solar exposure. Morphological
and textural modifications were followed by SEM and interferometric/confocal
profilometer.