The use of statistical modelling to justify a rational technology of steel production in the conditions of JSC Ural steel

In the conditions of JSC Ural Steel, the most costly technological task in the production of high-quality steel is to provide the required sulfur content. The analysis of the sulfur removal in the production of high quality steel in the technological conditions of JSC Ural Steel was performed. An increase in the sulfur content of the pig iron at 0,007-0,010% of the tapping from the blast furnace until used in an electric arc furnace was founded. The need for preliminary hot metal desulphurization before pouring in the electric arc furnace was justified. The method of calculating the cost of hot metal desulphurization, and the performance of the electric arc furnaces and ladle-furnace, depending on the quality of the initial charge on the sulfur content was developed. The methodology is based on material and thermal balances of processes, as well as statistical patterns of sulfur behavior during the hot metal desulphurization, the steel smelting in the electric arc furnaces and ladle-furnace. A program has been created for calculating the total costs for the production of steel of the required quality, which makes it possible to optimize the technology of steel production with the required sulfur content, taking into account the achievement of minimum production costs. The results of optimization technology of smelting high quality steel with using hot metal desulphurization at JSC Ural Steel were presented. In price terms in 2014, with an average sulfur content of the pig iron from the blast furnace 0.019%, the minimum cost of production of steel with a sulfur content of 0.005% (with the share of liquid pig iron in the metal stock to 40%) are provided at the organization ladle hot metal desulphurization to a sulfur content of 0.006%. With an estimated cost of building an installation for the hot metal desulphurization at 0.5 billion rubles, the payback period under conditions of JSC Ural Steel will be less than 5 years.