Density and Surface Tension of Slags from the Joint Smelting of Nickel Saprolite and Copper Pyrite Ores

The density and surface tension of homogeneous molten slags from the joint smelting of nickel saprolite and copper pyrite ores have been experimentally assessed (maximum bubble pressure method) using model samples of iron-containing slage (8.9 wt.% CaO + 11.8 wt.% MgO + 12.5 wt.% Al2O3 + 47.4 wt.% SiO2 + 13.3 wt.% FeO + 5.0 wt.% Fe2O3) and iron-free slag (12.5 wt.% CaO + 16.0 wt.% MgO + 9.4 wt.% Al2O3 + 58.3 wt.% SiO2), which represent the composition and structure of real prototypes in the temperature ranges of 1550-1300 degrees C and 1550-1400 degrees C, respectively. A decrease in temperature leads to an increase in the density and surface tension of these slags in the ranges of 1.85-2.21 and 2.23-2.29 gGreek ano teleiacm-3 and 144-250 and 340-345 mNGreek ano teleiam-1, respectively. The structural changes after the change over from the former composition to the latter one are due to the decrease in basicity from 0.7 to 0.6 and the replacement of Fe2+ by Ca2+ and Mg2+. The latter factor makes the major contribution to the increase of the characteristics themselves and their temperature coefficients (from -0.0015 to -0.0004 gGreek ano teleiacm-3Greek ano teleia degrees C-1 and from -0.4 to -0.1 mNGreek ano teleiam-1Greek ano teleia degrees C-1, respectively). The regression analysis of the experimental data was performed to obtain empirical models that accurately predict the density and surface tension of real slags from the smelting of copper and nickel raw materials in the temperature range considered. The results obtained can be used in developing and improving metallurgical technologies and in the glass and ceramic industries.