GB1419363A - Metal refining - Google Patents

Abstract

1419363 Refining metals by bottom blowing EISENWERK-GESELLSCHAFT MAXIMILIANSHUTTE mbH 30 May 1974 [31 May 1973] 23984/74 Heading C7D [Also in Division F4 In a metal refining furnace, a refining fluid e.g. oxygen is injected through a tuyere projecting through the furnace wall via a passage below the normal in use surface of the melt, and molten metal is discharged from the same passage on the completion of refining. In an open hearth furnace, Fig. 3, a lance 26 having an inner passage for oxygen to air, which may carry particulate additives, and an outer passage for a protective fluid e.g. a hydrocarbon, mist gas, steam or CO 2 , extends through the normal taphole and is sealed in place by a dolomite or other packing. The tuyere 26 is directed upwardly by a mound 48 of packing within the furnace. The end of the tuyere has a refractory sleeve 50. Metal may be heated in the furnace by fuel and air injected through the tuyere. Inert gas may be supplied to both passages at the end of the blowing period, until the furnace is to be tapped. When the gas flow is cut off, molten metal flows into the tuyere which may be destroyed, and issues from the taphole. The tuyere may be of ceramic material and may be coated with pitch.