転炉複合吹錬終点制御モデルの開発

抄録

For the endpoint control of top and bottom blowing process in BOF, a simplified mathematical model suitable for online application has been developed on the following procedure.
(1) The basic equations of oxygen consumption rate and temperature increase rate have been developed, which have the comprehensive characteristics in both low carbon range and high carbon range.
(2) Based on these basic equations, the fundamental curves of oxygen consumption and temperature increase, which show the progress of blowing, have been determined by analysis of actual operational data. The fundamental curve of dephosphorization also has been determined in the same way.
(3) The authors have developed a control model for endpoint carbon content and endpoint temperature of metal by using these fundamental curves.
At No. 2 BOF shop in Kashima Steel Works, the model is being used for the automatic blowing and contributes to the reduction of reblow ratio and furnace refractories.