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Sustainable development of steelmaking requires solving a number of environmental problems. Economically feasible and environmentally friendly recycling of slag wastes is of special concern. Research of the team representing National Metallurgical Academy of Ukraine, Royal Institute of Technology, Carnegie Mellon University and URS Corp revealed a possibility of the controlled phase transformations in the liquid silicate melts followed by formation of the magnetically susceptible compounds. This approach enables selective recovery of metal values from slag. In this paper, the results obtained and further research directions are discussed. A possibility to exploit physical properties of the transition metals, typical for the metallurgical slags (such as Fe, Mn, V and others), and corresponding specific properties of their compounds, such as non-stoichiometry, mixed valency, pseudomorphosis, thermodynamic stability etc, in production of value-added materials from slag wastes is discussed. The results of the studies of thermodynamics and kinetics of oxidation in slags followed by phase transformation with binary, ternary and complex oxides under various physicochemical conditions are discussed in the view of their application for production of the materials with predefined physical properties. Peculiarities of precipitation in slags with various basicities are analysed and demonstrate capacity of the proposed approach in the production of the material with a given structure and size - for example, nano-sized crystals with structure of spinel. The approaches towards industrial realization of the developed method are also discussed., QC 20131118

The experimental technique is developed to study the motion of nonconducting particles in the conducting liquid in crossed electrical and magnetic fields and applied to simulate a process of magnetite particle separation, formed during oxidizing of steelmaking slags. The calculated velocity of magnetite particles under action of the electromagnetic buoyancy force in molten steelmaking slags is 0.1-0.5 mm/min., QC 20140903

The experimental technique of mobilising non-conducting, nonmagnetic particles in conducting liquid in crossed electric and magnetic fields was investigated in order to find the way of the particle separation from the liquid steelmaking slags. The effect of the current density, magnetic field, size and shape of the particle on the particle velocity under action of the electromagnetic buoyancy force (EBF) in the electrolyte was analysed. Potential way of the application of obtained results to magnetite particle separation from liquid EAF slags are discussed., QC 20110609

The present work is aimed at the development of a new sustainable method for the utilisation of valuable elements from the steelmaking slag. In the framework of the innovative concept earlier proposed by the authors for utilisation of steelmaking slags, oxidation of iron mono-oxide in the liquid slag was studied experimentally in different atmospheres and in the temperature range 1623-1823 K using thermogravimetry technique. Synthetic (binary and ternary slag system) as well as industrial steelmaking slags were used in the experiments. Analysis of the reaction products was carried out using X-ray diffraction method. A possibility to transform the nonmagnetic iron bearing compounds to magnetite in the steelmaking slag by oxidation has been confirmed., QC 20101203

X-ray tomography was applied to investigating the structure of sinter mixture granules. Different components such as ore, concentrate, coke breeze and limestone were identified and their sizes and spatial distribution estimated. Classification of the granule structure by the thickness of the adhering fines layer in proportion to the whole granule radius has been estimated. Excessive amount of concentrate fines in a mixture leads to the increasing presence of granules with an adhering fines layer thicker than a half of the granule radius. Abnormal structures of granules have been observed in some cases, such as microgranules embedded in the adhering layer of bigger granules, granules formed as the result of two or more granules coalescing or granules formed without a nucleus particle, with a structure similar to pellets. (Authors.), X-ray tomography was applied to investigating the structure of sinter mixture granules. Different components such as ore, concentrate, coke breeze and limestone were identified and their sizes and spatial distribution estimated. Classification of the granule structure by the thickness of the adhering fines layer in proportion to the whole granule radius has been estimated. Excessive amount of concentrate fines in a mixture leads to the increasing presence of granules with an adhering fines layer thicker than a half of the granule radius. Abnormal structures of granules have been observed in some cases, such as microgranules embedded in the adhering layer of bigger granules, granules formed as the result of two or more granules coalescing or granules formed without a nucleus particle, with a structure similar to pellets. (Authors.)