The CaO - Al2O3 - CaSO4 - H2O system equilibrium states

Autor: S. Šaušová, I. Nerád, L. Števula
Rok vydání: 1994
Předmět:
Zdroj: Cement and Concrete Research. 24:259-266
ISSN: 0008-8846
DOI: 10.1016/0008-8846(94)90051-5
Popis: The equilibrium dissociation temperature of ettringite 3CaO.Al 2 O 3 . 3CaSO 4 .32H 2 O in the presence of liquid water as well as those of monoulphate 3CaO.Al 2 O 3 .CaSO 4 .12H 2 O in the presence of water vapor in relation to pressure were examined. At pressure from 150 up to 900 kPa ettringite in the presence of its saturated aqueous solution is thermally stable at temperature lower than 107 to 111 °C, respectively. 3CaO.Al 2 O 3 .CaSO 4 .12H 2 O and predominantly CaSO 4 are the decomposition products formed under conditions studied. The phases 3CaO.Al 2 O.CaSO 4 .10H 2 O(s), 3CaO.Al 2 O 3 .6H 2 O(s), CaSO 4 (s) and H 2 O(g) coexist in the equilibrium at the thermal dissociation of monosulphate under conditions employed. The 3CaO.Al 2 O 3 .CaSO 4 .10H 2 O thermal dissociation equilibrium temperatures reach values from 150 °C to 177 °C at the pressures of water vapor from 100 kPa to 900 kPa, respectively.
Databáze: OpenAIRE