Density Measurements of CaO-MnO-SiO2 Slags

Abstract

Density measurements of CaO-MnO-SiO2 slags were carried out using the Archimedean method. The density decreased with increasing temperature, and the negative temperature coefficient (-d rho/dT) was in the range of 1.46-3.10 x 10(-1) kg/m(3) K. At a fixed CaO content (25 wt%) and at a fixed SiO2 content (30 wt%), the density of CaO-MnO-SiO2 slag increased with increasing MnO content. The molar volumes of CaO, MnO and SiO2 at 1 773 K were estimated 21.0, 17.2, and 28.0 x 10(-6) m(3)/mol, respectively. The molar excess volume was expressed by V-Ex = Omega AX(SiO2) (1-X-SiO2), where Omega = 8.97 x 10(-6) m(3)/mol at 1 773 K. The thermal expansion coefficient decreased with increasing m(3)/mol because of the enhanced silicate network structure.