Kato T., Murakami K., Sugawara K., 2012, Carbon Reduction of Gypsum Produced from Flue Gas Desulfurization, Chemical Engineering Transactions, 29, 805-810.
In this study, the changes in the chemical form of calcium on reduction with solid carbon were investigated in order to develop a process for the regeneration of CaO from spent gypsum at low temperatures. Calcium sulfate dihydrate was used as a model compound for gypsum; it was mixed with solid carbon and heated to a terminal temperature of 1100 °C. CaO was produced from 900 °C, after the formation of CaS, by the reaction of CaSO4 and CaS, with the consumption of solid carbon. There is an optimum amount of solid carbon that should be added to produce CaO efficiently from gypsum. Kinetic analyses of the formation of CaO from gypsum by carbon reduction during heat treatment of a mixture of solid carbon and gypsum were conducted.
