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A mathematical model was developed to simulate gas–matte–slag three-phase flow in ISASMELT furnace with a top-submerged lance. An experimentally verified simulation model was established by adopting a VOF multiphase model coupled with a realizable k−e turbulence model. The flow field in ISASMELT furnace during the top-blowing process can be divided into 5 parts including injection, splashing, strong-loop, weak-loop, and sedimentation zones. The optimal lance diameter of 0.4 m and lance immersion depth of 0.4 m which have been applied in industry were obtained by investigating the mean velocity, phase volume fraction, splashing quantity, and wall shear stress distributions. Compared to the original operating conditions, a higher concentrate feeding rate of 140 t/h, a longer lance life of > 15 days, and a longer furnace life of 56 months were achieved for an industrial ISASMELT furnace operation under the improved lance diameter and immersion depth.

To promote the innovation of raw magnesium production technology, an integrated calcination and silicothermic reduction short process for magnesium production was experimentally studied on the laboratory scale in this article. The influences of the thermal decomposition temperature, silicothermic reduction temperature, pelletizing pressures and silicon ratio on the characteristics of producing the magnesium by the short process was studied. The crosslinking effect, including reactions between CO2 decomposed from dolomite and metal elements in ferrosilicon, microstructure change at thermal decomposition and silicothermic reduction stages, was analyzed and discussed. In addition, comparison of the magnesium reduction rate and production efficiency between the new short process and the traditional Pidgeon process was made. The results indicated that the decomposition and reduction temperatures have a more significant influence on the magnesium reduction process than the pelletizing pressure and silicon ratio. A decomposition temperature 1100 °C was proven to be favorable for improving the magnesium reduction rate and production efficiency of the new short process. It was also found that the integrated short process for magnesium production can reach the same total reduction rate and has lower efficiency compared to the traditional process. The decrease of magnesium production efficiency in the new short process was expected to result from reduction of the contact area and hindering of diffusion between CaO·MgO molecules and Si(Fe) atoms because of the microstructure change and ferrosilicon consumption by the reactions between CO2 and metal elements in ferrosilicon. Preparing briquettes with additives of binder or ultrafine particles of raw materials was proposed and considered for further study to improve the production efficiency.

More than 80 pct of copper matte in the world is refined by a Peirce–Smith converter (PSC), but there still exist a number of problems restricting the productivity of PSC. A novel view for improving the copper PSC process was proposed by investigating the bubble distribution and surface splashing through water model experiments. The operating parameters of tuyere diameter (d), liquid height (H), and gas flow rate (Q) were determined, and dimensionless equations were developed that calculate the bubble surface area per unit bath volume, Ab/(HL); bubble number, Nb; and vertical and horizontal splashing distances, x/y, with errors less than 5 pct. From the application of the similarity principles on the results of the water model experiments, the optimal industrial parameters were determined as d = 0.03 m, H = 1.8 m, and Q = 30,000 to 35,000 Nm3/h. These results indicate that the current industrial PSCs are well within the ranges of these dimensions, with the possible exception of the tuyere diameter, which is typically 0.05 m.