CALCULATIONS TO SIMULATE THE DEVELOPMENT OF NITROGEN CONCENTRATIONS IN THE LD PROCESS

The main variables influencing the final nitrogen concentration in cru de steel have hitherto been determined by the method of multiple regre ssion. The method yields no information about the development of the c oncentrations throughout the blow. Presented in this work therefore is a simulation model to describe the development of the nitrogen in the BOF process. Taken as a basis for the model are the technology of the BOF process, the principle of transitory stir-degassing, and the ther modynamics of the nitrogen. Parametric studies illustrate the influenc e of process variables on the nitrogen development and on the final co ncentrations. The influence of the stirring action on the development of the nitrogen concentrations throughout the blow is examined with th e aid of a circulation model. The calculated data from the parametric studies reveal a convincing correspondence with operational data. The evolved simulation model makes it possible to optimize the process tec hnology with respect to the final nitrogen concentrations in the crude steel.