Mixing of the metal and mass transfer during the tapping of a semifinished product from an oxygen converter

Abstract

The tapping operation is very important in the use of oxygen converters to obtain semifinished products, since this is the point at which the ultimate chemical composition of the steel is formed, the metal undergoes deoxidation, and slag is formed for use in subsequent out-of-furnace treatments. This article studies the process of the mixing of the metal in the ladle during the tapping of 240-ton heats of carbon and low-alloy steels from converters at EKO Stahl (in Germany). To obtain the maximum effect during tapping, the total amount of power supplied for mixing of the metal in the ladle by the falling stream and the injected gas must be kept at a continuously high level. One way of achieving this is increasing the amount of gas injected during the second period of the tapping operation.