Converter blowing control method and converter blowing control system

Patent metadata

Field	Value
Publication number	US-2024035104-A1
Application number	US-202118011596-A
Country	US
Kind code	A1
Filing date	Apr 30, 2021
Priority date	Jul 1, 2020
Publication date	Feb 1, 2024
Grant date	—

Abstract

A converter blowing control method includes: calculating, by heat balance calculation and material balance calculation, an amount of oxygen supplied and an amount of a cooling material or a rising heat material charged to control a temperature and a component concentration of molten steel at end of blowing in a converter to target values; controlling the blowing in the converter based on the calculated amount of oxygen supplied and the calculated amount of a cooling material or a rising heat material charged; estimating a pre-blowing molten iron temperature that is a temperature of molten iron used as a raw material for blowing to be a target of the heat balance calculation, charged into the converter, and is in a state immediately before start of the blowing; and using the estimated pre-blowing molten iron temperature as a charged molten iron temperature in the heat balance calculation.

First claim

1 .- 15 . (canceled)

16 . A converter blowing control method comprising:
calculating, by heat balance calculation and material balance calculation, an amount of oxygen to be supplied and an amount of a cooling material or a rising heat material to be charged to control a temperature and a component concentration of molten steel at end of blowing in a converter to target values; and controlling the blowing in the converter based on the calculated amount of oxygen to be supplied and the calculated amount of a cooling material or a rising heat material to be charged, wherein the method comprises:
estimating a pre-blowing molten iron temperature that is a temperature of molten iron used as a raw material for blowing to be a target of the heat balance calculation, charged into the converter, and is in a state immediately before start of the blowing, and
using the estimated pre-blowing molten iron temperature as a charged molten iron temperature in the heat balance calculation.

17 . A converter blowing control method comprising:
sequentially estimating a temperature and a component concentration of molten metal at progress of blowing by sequentially performing heat balance calculation and material balance calculation during the blowing based on operation conditions and a measured value of a converter obtained at start of and during the blowing in the converter; and controlling the blowing in the converter based on the estimated temperature and the estimated component concentration of the molten metal, wherein the method comprises:
estimating a pre-blowing molten iron temperature that is a temperature of molten iron used as a raw material for blowing to be a target of the heat balance calculation, charged into the converter, and is in a state immediately before start of the blowing, and
using the estimated pre-blowing molten iron temperature as a charged molten iron temperature in the heat balance calculation.

18 . The converter blowing control method according to claim 16 , wherein a value obtained by adding a post-charging molten iron temperature change amount to a molten iron temperature during charging is used as the charged molten iron temperature used in the heat balance calculation, the post-charging molten iron temperature change amount being a molten iron temperature change amount in a period from when the molten iron is charged into the converter to when the blowing starts, and the molten iron temperature during charging being a temperature of the molten iron measured during a period when the molten iron used as the raw material for the blowing to be a target of the heat balance calculation is charged into the converter.

19 . The converter blowing control method according to claim 16 , wherein a value obtained by adding a pre-charging molten iron temperature change amount and a post-charging molten iron temperature change amount to a pre-charging molten iron temperature is used as the charged molten iron temperature used in the heat balance calculation, the pre-charging molten iron temperature being a temperature of the molten iron measured during a period when the molten iron used as the raw material for the blowing to be a target of the heat balance calculation is held in a molten iron holding container before being charged into the converter, the pre-charging molten iron temperature change amount being a molten iron temperature change amount during a period from measurement of the pre-charging molten iron temperature to charging of the molten iron into the converter, and the post-charging molten iron temperature change amount being a molten iron temperature change amount during a period from when the molten iron is charged into the converter to when the blowing starts.

20 . The converter blowing control method according to claim 19 , wherein the post-charging molten iron temperature change amount is determined based on a difference between a back-calculated value of the charged molten iron temperature back-calculated from the heat balance calculation to match a measured value of a molten metal temperature during blowing performed in past blowing and the molten iron temperature during charging in the past blowing.

21 . The converter blowing control method according to claim 20 , wherein the post-charging molten iron temperature change amount is determined for further consideration of at least one of a time from when a previous charge of a target charge is discharged to when the molten iron of the target charge is charged and a time from when the molten iron of the target charge is charged to when the blowing starts.

22 . The converter blowing control method according to claim 19 , wherein the pre-charging molten iron temperature change amount is determined based on a difference between the pre-charging molten iron temperature in the past blowing and the molten iron temperature during charging in the past blowing.

23 . The converter blowing control method according to claim 22 , wherein the pre-charging molten iron temperature change amount is determined for further consideration of at least one of an elapsed time from a time at which the molten iron in the previous charge of the target charge is discharged to a receiving time at which the molten iron to be used for blowing of the target charge is received in a molten iron holding container to receive the molten iron to be used for blowing of the target charge and a time from when the pre-charging molten iron temperature is measured to when the molten iron is charged into the converter.

24 . A converter blowing control system comprising:
a first computer configured to calculate, by heat balance calculation and material balance calculation, an amount of oxygen to be supplied to a converter and an amount of a cooling material or a rising heat material to be charged into the converter to control a temperature and a component concentration of molten steel at end of blowing in the converter to target values; a control device configured to control the blowing in the converter based on the amount of oxygen to be supplied to the converter and the amount of a cooling material or a rising heat material to be charged into the converter calculated by the first computer; a second computer configured to calculate a pre-blowing molten iron temperature that is a temperature of molten iron used as a raw material for the blowing in the converter, is charged into the converter, and is in a state immediately before start of the blowing; and at least one of
a third computer configured to calculate, as a molten iron temperature during charging, a temperature of the molten iron used as the raw material for the blowing to be a target of the heat balance calculation by using two-color temperature information of the molten iron during a period when the molten iron is charged into the converter,
a fourth computer configured to calculate a pre-charging molten iron temperature change amount that is a molten iron temperature change amount during a period from when a pre-charging molten iron temperature is measured to when the molten iron is charged into the converter, the pre-charging molten iron temperature being a temperature of the molten iron during a period when the molten iron used as the raw material for the blowing to be a target of the heat balance calculation is held in a molten iron holding container before being charged into the converter, and
a fifth computer configured to calculate a post-charging molten iron temperature change amount that is a molten iron temperature change amount in a period from when the molten iron used as the raw material for the blowing to be a target of the heat balance calculation is charged into the converter to when the blowing starts, wherein

Assignees

• Jfe Steel Corp

Inventors

• Sugino Tomohiro
• Takahashi Yukio
• Kawabata Ryo
• Amano Shota
• Kikuchi Naoki
• Kase Hiroto
• Nonaka Toshiki

Classifications

• C21C5/30 Primary

  Regulating or controlling the blowing · CPC title

• C21C5/4673

  Measuring and sampling devices · CPC title

• C21C7/04

  Removing impurities by adding a treating agent · CPC title

• F27B1/28

  Arrangements of monitoring devices, of indicators, of alarm devices · CPC title

• F27D19/00

  Arrangements of controlling devices · CPC title