Stoyanov A. "Development and application of steel injection treatment by solid slag forming compounds technology"

Dissertation work is devoted to the urgent scientific and technical task in technology development of injection out-of-furnace steel treatment by powder-like solid slag forming compounds with special physicochemical properties, their technology of production and application working-off. Physicochemical model of metal ladle refinement at injection of powder-like lime containing materials is developed. Evaluation of the degree of diffusion processes completeness at complex treatment of steel by lump and powder-like solid slag forming compounds is held. Data of the reagent's required range of dispersion and parameters of powder-like desulphurizer injection are obtained with the help of computational modeling. Main physicochemical properties of lime-based slag-like refining compounds are investigated, search and testing of the new surface-active substances, which allowed to prevent the hydration of powder lime during 24 days, is held. Laboratory investigations of lime-based multi-component slag compounds'desulphurizing capacities are obtained with the help of contemporary high-temperature modeling procedures. Phase composition of the slag component formed in the deep volume of metal is obtained. Technological processes of lime-based powder-like materials preparation and steel injection treatment are developed and improved. They were tested at the "Azovsteel" industrial complex, whereby the metal refinement's results stability with energy and resources economy was provided, possibility of steel quality high parameters achievement was assigned.