Search International and National Patent Collections

1. (WO2018180892) METHOD FOR OPERATING BLAST FURNACE

Pub. No.:    WO/2018/180892    International Application No.:    PCT/JP2018/011417
Publication Date: Fri Oct 05 01:59:59 CEST 2018 International Filing Date: Fri Mar 23 00:59:59 CET 2018
IPC: C21B 5/00
Applicants: JFE STEEL CORPORATION
JFEスチール株式会社
Inventors: YAMAMOTO Naoki
山本 尚貴
MURAO Akinori
村尾 明紀
HORIKOSHI Hiroyuki
堀越 裕之
MIYAGOE Ryosuke
宮越 亮丞
MORIYA Kota
盛家 晃太
FUKADA Kiyoshi
深田 喜代志
Title: METHOD FOR OPERATING BLAST FURNACE
Abstract:
Provided is a method for operating a blast furnace in which hot air is supplied from a hot air pipe to the inside of a blowpipe the tip of which is connected to a tuyere of a blast furnace, the hot air is supplied to the inside of the blast furnace from the tuyere via the inside of the blowpipe, a first solid reducing agent is blown from an inside pipe of a first double pipe lance the tip of which is inserted into the inside of the blowpipe and a combustion supporting gas is blown from an outside pipe of the first double pipe lance simultaneously to the inside of the blowpipe so as to supply the same to the inside of the furnace from the tuyere, and a second solid reducing agent is blown from an inside pipe of a second double pipe lance the tip of which is inserted into the inside of the blowpipe and an easily combustible reducing gas is blown from an outside pipe of the second double pipe lance simultaneously to the inside of the blowpipe so as to supply the same to the inside of the furnace from the tuyere, wherein the method is characterized in that index A for blow-in of the combustion supporting gas defined by Equation (1) is set at 100 – 100,000, and index B for blow-in of the easily combustible reducing gas defined by Equation (2) is set at 300 – 100,000. A = V1 × F1 ... (1), B = V2 × F2 ... (2)