Study of the features of interaction of gas jets with liquid bath at top blowing through an annular coaxial nozzle

Abstract

. Technological, technical and economic indicators of BOF heat largely depend on the organization of the blowing mode. Under the current conditions of instable supply and the quality of charge materials and energy carriers, as well as the need to increase the intensity and quality of the blowing process, the studies on developing new design of tip for oxygen lance, the base element of it being a composite annular coaxial nozzle. The studies were carried out on “cold” physical models and on models of BOF convertor with hot metal. Comparative analysis of the interaction of oxygen jet with a liquid bath, using an annular coaxial nozzle (the experimental tip), and a tip having four nozzles (the comparative tip) were accomplished. It was determined, that the jet from experimental tip has a higher dynamic pressure and depth of penetration into the liquid melt without increased metal splash. While blowing through the lance with the experimental tip, a “hard” blowing pattern with the formation of a smaller amount of slag were observed. The “hard” nature of the blowing was eliminated due to the additional lateral cylindrical nozzles. As a result of the changes more active absorption of lime than at comparative heats was reached. It was revealed that the use of the perfected experimental lance tip contributes to a higher bath heating and a decrease of dust emission.