DISTRIBUTION OF METAL DROPLETS BETWEEN GAS AND SLAG PHASES DURING BUCKET BATH BLOWING

Losses of metal with slag falling from the surface of the molten cast iron at the loading plants after the end of the ladle desulfurization process and losses with metal drops leaving the ladle bath when gas bubbles exit and break on its surface affect the cost and energy efficiency of the operation. Blowing a mixture of dispersed magnesium with lime into the ladle bath in the conditions of cast iron desulphurization plant PrJSC "KAMET—STEEL" leads to an increase in both the viscosity and the mass of the ladle slag, with an increase in the metal content in the form of balls in the ladle slag to 65— 80 %. 
The purpose of the work is to study the peculiarities of the removal of metal drops into the surrounding space, which are formed after the bursting of gas bubbles, when they fall on the surface of the ladle bath. To realize the set goal, a series of high—temperature experiments with simulation of bath purging during bucket desulfurization of cast iron were conducted in the laboratory conditions of the Department of metallurgy of ferrous metals and pressure metal processing of DSTU. A study of the features of removal and loss of cast iron with drops during overflows of the latter shows that some of the drops explode in flight with the release of brown smoke and the formation of drops of smaller sizes than the "mother" drop. Despite favorable conditions, part of the drops reach the surface of the bath or fly beyond it without exploding. Using the obtained experimental data, a model of the release of gas bubbles on the surface of the bath and an algorithm for calculating the indicators of the movement of metal drops formed from a metal film on the surface of gas bubbles after their rupture are proposed. It was determined that the most probable condition for blowing out the bath in a 230-ton bucket is the departure of metal drops from the surface of the bath at angles in the range of 35...45 degrees. The decisive role of the physicochemical properties of the slag cover and the expediency of further improvement of the blowing mode and slag regime of ladle desulphurization of processing cast iron have been confirmed.