Avoiding Sloppy BOS Process Behavior

摘要

Extreme BOS processing conditions may sometimes lead to excessive slag foaming and slopping, resulting in considerable amounts of metallic losses, equipment damage and un-necessary production disturbances. Control of slag formation without slopping is primarily accomplished by taking preventive measures. If static control measures are not effective then in-blow control measures are required and for these to be successful, it is necessary to employ a method for predicting slopping events. Such a system, utilizing BOS vessel vibration measurement, is presently being re-introduced at SSAB's BOS plant in Lulea, Sweden.A deep study into the causes of slopping has been carried out for a 114 tonne LD/LBE vessel, equipped with an automatic system for slopping registration using image analysis. Improved slopping control was achieved by developing a novel lance control scheme, with a new approach to the adjustment of lance position according to scrap quality and ore additions.