| 摘要 |
<p>A process for determining the end of blowing during the refining of a steel melt in a converter is described, the carbon drop rate being determined from the incidence of carbon monoxide and carbon dioxide in the off-gas stream, which is measured by analysis of the off-gas from the converter, and the end of blowing which is provided for a predetermined final carbon content of the steel melt, when the carbon drop rate falls below a predetermined threshold, is calculated from the carbon drop rate in accordance with a predeterminable relationship between the carbon drop rate and the residual carbon content, which can be predetermined for low residual carbon contents. To improve the accuracy of the process, it is proposed for the residual carbon content of the molten steel, after the incidence of carbon monoxide and/or carbon dioxide, based on the off-gas stream, has fallen below an upper threshold, which is a function of the analysis time of the off-gas analysis and is empirically determined, to be calculated on an on-going basis from the carbon drop rate, in accordance with the predetermined relationship between carbon drop rate and residual carbon content, and to be compared with the predetermined set value for the final carbon content for determining the end of the refining operation. <IMAGE></p> |
