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A two-dimensional mold model coupled multiphase flow, heat transfer, solidification and mold oscillation was established based on the casting parameters of the mold of plant. The accuracy of the model was verified by comparing the measured by plant and calculated mold powder consumption under the same casting conditions. The mechanism of mold powder consumption and lubrication was analyzed based on the non-sinusoidal oscillation mode, and the effect of non-sinusoidal oscillation parameters on mold powder consumption was discussed. Mold powder consumption was determined by the downward flow velocity of liquid mold powder and the thickness of liquid mold powder film, the liquid mold powder consumption decreased with the decrease of those. When the mold moved downward, the mold powder thickness and downward flow velocity decreased, the minimum mold powder consumption reached at the middle of the negative strip time, and the variation was to opposite when the mold moved upward, the maximum mold powder consumption appeared during the positive strip time. With the decrease of casting speed and modification ratio, and increase of oscillation frequency and oscillation amplitude, the mold powder consumption had the tendency to increase. The nonlinear regression equation was fitted by the Levenberg–Marquardt method combined with the universal global optimization method to evaluate mold powder consumption.

The initial solidification of the shell and the effect of the negative strip on oscillation marks were studied during the oscillation of the mold. A two-dimensional model was established concerning mold oscillation, which was coupled with fluid flow, heat transfer, and solidification, and the validity of the model was verified. The results show that oscillation marks were formed at the negative strip stage and that the quality of the slabs can be improved by reducing the duration of the negative strip stage. During the negative strip stage, the shell was affected by the strong backflow of liquid slag and the pressure on the surface sharply increased, resulting in the formation of a depression oscillation mark on the shell. The effects of the negative strip stage on the initial solidified shell during each cycle were compared. As the depth of the oscillation mark decreased, the upward shear stress on the shell’s surface increased, without the occurrence of a negative strip stage during one cycle. The results provided a new method for reducing oscillation marks and are of great significance for improving casting slabs’ quality.

In this paper, a new iron-carbon micro-electrolytic filler for wastewater treatment was prepared using the blast furnace dust. The effects of preparation conditions on the performance of the filler during the wastewater treatment were investigated. The optimal preparation conditions of the filler were obtained, which provided an experimental theoretical basis for the use of metallurgical dust sludge in the preparation of micro-electrolytic fillers. From the results of treating methyl orange-simulated wastewater with fillers of different preparation conditions, it could be obtained that the improvement of the filler processing performance requires a suitable iron to carbon ratio, sintering time, and sintering temperature. The optimum preparation conditions were a 1:2 iron-carbon ratio, 30 min sintering time, and 1100 °C sintering temperature. The effect of treatment conditions on the performance of the iron-carbon micro-electrolytic filler was also investigated. The results showed that increasing the filler addition, increasing the treatment temperature, and decreasing the initial pH could effectively improve the treatment efficiency of the filler for methyl orange-simulated wastewater. More than 99% of the methyl orange could be removed in the wastewater under the conditions of 5 g of filler, 40 °C, and pH = 3.