PROCESS FOR THE CONDITIONING OF SLAG DURING METAL BATH REFINING

A ferrous melt, e.g. of steel, is refined beneath a slag layer by blowing from above with an oxygen-containing gas through a lance and by bubbling an inert gas through the melt from the bottom. According to the invention, the consistency of the slag layer and/or its level is continuously detected on the one hand and the rate of decarburation of the bath is detected on the other hand and in response to these measurements the volume rate of flow of the bubbling gas is controlled on the one hand to maintain a predetermined spacing of the slag layer from the head of the lance and, on the other hand, a fluid consistency of the slag.