THE INFLUENCE OF FGD GYPSUM DEHYDRATION PARAMETERS ON β-HEMIHYDRATE CALCIUM SULFATE PROPERTIES

Abstract

In this research, the influence of flue gas desulphurization gypsum (known as smoke gypsum) dehydration conditions (temperature and duration) on the β-hemihydrate calcium sulfate formation, the crystal morphology and properties was investigated. The used raw materials and the obtained gypsum binder properties were studied by chemical analysis and instrumental methods. β-Hemihydrate gypsum formation was found to accelerate with increasing the dehydration at 120–160 °C a temperature ranging within. The SEM analysis of the obtained product showed that prismatic crystals of calcium sulphate hemihydrate had been formed. The crystal size influenced the physical-mechanical properties of β-hemihydrate gypsum. At higher temperatures, the obtained gypsum binder hydrated faster, and formatted samples of compressive strength was greater than that derived at lower temperatures.

DOI: http://dx.doi.org/10.5755/j01.ct.60.2.1603