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Purpose. The research purpose is to substantiate the use of biocoke as a fuel in the iron ore sintering, as well as its influence on the performance and properties of the resulting sinter. To completely replace conventional coke breeze, biocoke is produced using 5 wt.% biomass wood pellets at different carbonization temperatures of 950 or 1100°C. Further, the influence of biocoke on the sintering process and the sinter quality is studied at a high proportion of biomass pellets of 10, 15, 30, 45 wt.% and a carbonization temperature of 950°C. Methods. Carbonization is performed in shaft-type electric furnaces to produce laboratory coke or biocoke. Afterward, the sintering of iron ores is conducted on a sinter plant. To assess the sintering process and the quality of the resulting sinter, the filtration rate is determined on a laboratory sinter plant using a vane anemometer designed to measure the directional flow average velocity under industrial conditions. The sinter reducibility is studied using a vertical heating furnace to assess the effect of coke and biocoke on the sinter’s physical-chemical properties. Findings. It has been determined that biocoke, carbonized at a temperature of 950°C, has good prospects and potential for a shift to a sustainable process of iron ore sintering. Originality. It has been proven that biocoke with a biomass pellet ratio of up to 15 wt.%, obtained at a temperature of 950°C, does not affect the parameters characterizing the sintering process. The sinter strength indicators correspond to the use of 100 wt.% conventional coke breeze. Biocoke used with a high proportion of biomass pellets of 30 and 45 wt.% causes a deterioration in the sinter quality. Practical implications. The results of using biocoke with the addition of 5-15 wt.% biomass pellets and at a temperature of 950°C are within the standard deviation, which makes it possible to use biocoke with 15 wt.% biomass pellets instead of industrial coke breeze.

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The paper shows the results of a study of the influence of the cut-off method of the slag by using destructible plugs on the quantitative indicators of the redistribution of slag and metal in the steel ladle during the metal tapping operation from the converter. The laboratory setup simulates a real 160-ton industrial top-blown oxygen converter, and a steel ladle at a scale of 1:18 has been used to fulfill the study. Water was chosen as a liquid steel imitator, and machine oil was chosen for slag with parameters that ensure the similarity of physical parameters in the metal-slag system. The physical modelling of the tapping process of a two-phase converter bath in the case of a destructible plug in the tap hole compared to the tapping option without it showed a significant positive effect of the presence of the plug in the initial period from the moment the converter is tilted.

It was studied in the article the possibility of intensification of removal of non-metallic inclusions in a teeming ladle during holding without any additional external influences on the metal (argon blowing or electromagnetic stirring). Increasing the efficiency of removal of non-metallic inclusions is achieved by creating in a teeming ladle during tapping a circulation pattern that accelerate the floating of inclusions. The described effect is achieved by using a rational shape of the workspace of the teeming ladle, which has been found as a result of "water" modelling. To carry out the experiment, the authors have proposed the similarity numbers describing the floating of non-metallic inclusions in the ladle during the tapping and for some time after its completion. On the basis of the proposed similarity numbers, an experimental facility and the experimental method were developed. In the course of the experiment, the construction of linings of several types was studied. Ladles of the best design provide by 16-19 % faster removal of non-metallic inclusions from steel than in ladles of conventional design. The results of the research can be useful for mini-plants and enterprises with ladles of small capacity, where the use of argon blowing and electromagnetic stirring is technologically and economically unreasonable.