METHOD OF OBTAINING MOLTEN PIG IRON AND APPARATUS THEREFOR

摘要

A process for producing molten pig iron uses direct reduction of iron ore in a pre-reduction stage followed by a final reduction stage. In the pre-reduction stage iron ore is pre-reduced in a melting cyclone (1) by means of a reducing process gas originating from the final reduction stage. A post-combustion occurs in the reducing process gas in the melting cyclone so that said iron ore in said melting cyclone is at least partly melted. The partly melted iron ore passes downwardly into a metallurgical vessel (4) situated beneath the cyclone in which the final reduction takes place by supply of coal and oxygen, thereby forming a reducing process gas. A partial post-combustion occurs in the reducing process gas in the metallurgical vessel by means of said oxygen supplied thereto. The post-combustion ratio of the gas on exiting the metallurgical vessel is not more than 0.55. The coal is supplied directly into the slag layer (7) so that said partial post-combustion in said metallurgical vessel is at least partly effected in the slag layer.