METHOD FOR PRETREATMENT OF MOLTEN IRON AND METHOD FOR REFINING

Title:

METHOD FOR PRETREATMENT OF MOLTEN IRON AND METHOD FOR REFINING

Document Type and Number:

WIPO Patent Application WO/2003/029498

Kind Code:

A1

Abstract:

A method for the pretreatment of a molten iron wherein use is made of a top−blown refining vessel, and the desiliconization and the dephosphorization of the molten iron are carried out by blowing a flux having a primary component which contains iron oxide and at least one of calcium oxide and limestone into the molten iron, characterized in that a carbon source is blown into the molten iron during desiliconization and the blowing of the carbon source is started prior to the start of the blowing of the flux. The blowing of the flux is preferably started after a [Si] concentration has been lowered to 0.15 mass % and&sol or after the blowing of the carbon source has been completed. The above method for the pretreatment of a molten iron and refining allows the refining which does not use fluorspar both in the pretreatment of a molten iron and the decarbinization steps, the minimization of formation of a slag for dephosphorization in the decarbonization step, and the improvement of the degree of allowance of heat through the efficient addition of a carbon source into a molten iron.

Inventors:

HIRATA HIROSHI
ISHII HIROMI
HAYASHI HIROAKI
OGAWA YUJI
SASAKI NAOTO

Application Number:

PCT/JP2002/010108

Publication Date:

April 10, 2003

Filing Date:

September 27, 2002

Export Citation:

Click for automatic bibliography generation Help

Assignee:

NIPPON STEEL CORP (JP)

International Classes:

C21C1/02; C21C1/04; C21C7/00; C21C7/04; C21C7/068; C21C5/32; (IPC1-7): C21C1/02; C21C1/04; C21C7/068

Foreign References:

JPS60221511A	1985-11-06
JPH02228412A	1990-09-11
JPH0920914A	1997-01-21
JPH07278636A	1995-10-24

Other References: