Dimentjiev A. Technological improvement of control for open-hearth operation aiming to increase the efficiency of the blast furnace

The object of study: processes in the blast furnace hearth during filling and emptying. The subject of the study: central and peripheral inactive stagnant zone in the blast furnace hearth. Research Methods: in carrying out the work were used: laboratory studies to determine the lines of flow of the slag at the bottom of the blast furnace; methods of physical modeling; mathematical statistics; passive and active experiments in the steel unit; Comparative analysis of the data; use the new controls work blast furnace hearth. In the thesis on the basis of scientific, theoretical researches and industrial investigations an important scientific and engineering task has been solved especially reducing a cost of iron production due to improving a drainage conditions in the hearth if it contains low-level zones. The reasons of their appearing have been presented. Their grading is proposed as well as a method of their determining in the furnace using a system of control for an open-hearth state. Their impact on operation of the furnace is determined. Technological measures for their prevention have been developed. Technological improvement of open-hearth melting due to improving the drainage conditions in the hearth at blast furnaces №1 and №5 at PJSC "Alchevsk Iron-and-Steel Works" caused economic effect of 3 627 636 UAH.