Furnace state estimation device, furnace state estimation method, and molten steel production method

Patent metadata

Field	Value
Publication number	US-2025179597-A1
Application number	US-202218703715-A
Country	US
Kind code	A1
Filing date	Nov 11, 2022
Priority date	Nov 29, 2021
Publication date	Jun 5, 2025
Grant date	—

Abstract

A furnace state estimation device ( 1 ) including: an input unit ( 11 ) configured to receive track record information and conditions of refining treatment; a model determination unit ( 14 ) configured to determine model parameters using past model parameters; a furnace state calculation unit ( 15 ) configured to calculate state quantities, including temperature and component concentration of molten metal and component concentration of slag, in a furnace, using the determined model parameters; and a model parameter calculation unit ( 13 ) configured to calculate model parameters in the refining treatment of the target charge, based on an evaluation function that includes terms representing a mass balance error and a heat balance error in the furnace from beginning to end of a particular period of time in the refining treatment, using track record information including results of the refining treatment of the target charge.

First claim

1 . A furnace state estimation device comprising:
an input unit configured to receive track record information and conditions of refining treatment, the track record information including measurement results of temperature and component concentration of molten metal and component concentration of slag before start of or during the refining treatment in refining equipment and measurement results regarding the refining equipment that include flow rate and component concentration of exhaust gas discharged from the refining equipment; a model determination unit configured to determine model parameters in the refining treatment of a target charge using past model parameters acquired from a database that stores model parameters for models related to blowing reaction in the refining equipment, the track record information, and the conditions of refining treatment; a furnace state calculation unit configured to calculate state quantities, including temperature and component concentration of the molten metal and component concentration of the slag, in a furnace, using the determined model parameters; and a model parameter calculation unit configured to calculate model parameters in the refining treatment of the target charge, based on an evaluation function that includes terms representing a mass balance error and a heat balance error in the furnace from beginning to end of a particular period of time in the refining treatment, using the track record information including results of the refining treatment of the target charge.

2 . The furnace state estimation device according to claim 1 , wherein the model determination unit is configured to determine the model parameters in the refining treatment of the target charge, by averaging model parameters for past refining treatment wherein conditions are similar to the conditions of the refining treatment of the target charge among the past model parameters stored in the database.

3 . The furnace state estimation device according to claim 1 , wherein the model determination unit is configured to model relationship between the past model parameters stored in the database and the conditions of refining treatment, including counts of times the treatment is performed, dates and times of the treatment, and/or counts of times the refining equipment is used in the refining treatment, and determine the model parameters for the refining treatment of the target charge based on a model.

4 . The furnace state estimation device according to claim 1 , wherein the model parameters include a coefficient or a constant term that corrects an integrated amount of carbon charged into the furnace over a particular period of time, an integrated amount of carbon discharged out of the furnace over a particular period of time, an amount of oxygen charged into the furnace, an amount of oxygen discharged out of the furnace, an amount of oxygen used for oxidation of various metallic impurities in the molten metal, and/or an integrated amount of change in the temperature of the molten metal over a particular period of time due to changes in an amount of heat in the furnace.

5 . The furnace state estimation device according to claim 1 , wherein the evaluation function is formed by a weighted sum of a term representing carbon balance, a term representing oxygen balance, and a term representing heat balance.

6 . A furnace state estimation method to be executed by a furnace state estimation device, the furnace state estimation method comprising:
an input step of receiving track record information and conditions of refining treatment, the track record information including measurement results of temperature and component concentration of molten metal and component concentration of slag before start of or during the refining treatment in refining equipment and measurement results regarding the refining equipment that include flow rate and component concentration of exhaust gas discharged from the refining equipment; a model determination step of determining model parameters in the refining treatment of a target charge using past model parameters acquired from a database that stores model parameters for models related to blowing reaction in the refining equipment, the track record information, and the conditions of refining treatment; a furnace state calculation step of calculating state quantities, including temperature and component concentration of the molten metal and component concentration of the slag, in a furnace, using the determined model parameters; and a model parameter calculation step of calculating model parameters in the refining treatment of the target charge, based on an evaluation function that includes terms representing a mass balance error and a heat balance error in the furnace from beginning to end of a particular period of time in the refining treatment, using the track record information including results of the refining treatment of the target charge.

7 . The furnace state estimation method according to claim 6 , wherein the model determination step is configured to determine the model parameters in the refining treatment of the target charge, by averaging model parameters for past refining treatment wherein conditions are similar to the conditions of the refining treatment of the target charge among the past model parameters stored in the database.

8 . The furnace state estimation method according to claim 6 , wherein the model determination step is configured to model relationship between the past model parameters stored in the database and the conditions of refining treatment, including counts of times the treatment is performed, dates and times of the treatment, and/or counts of times the refining equipment is used in the refining treatment, and determine the model parameters for the refining treatment of the target charge based on a model.

9 . A molten steel production method comprising
producing molten steel, by determining flow rate and speed of top-blown oxygen, height of a top-blowing lance, flow rate of bottom-blown gas, charge amount and charge timing of auxiliary raw materials, such as lime or iron ore, timing for sampling molten metal, and/or timing for terminating blowing, based on the temperature and the component concentration of the molten metal and the component concentration of the slag estimated by the furnace state estimation method according to claim 6 , and performing refining operation.

Assignees

• Jfe Steel Corp

Inventors

• Kase Hiroto
• Sugino Tomohiro
• Kawabata Ryo
• Kimura Yuki

Classifications

• C21C2300/06

  Modeling of the process, e.g. for control purposes; CII · CPC title

• C21C5/4673 Primary

  Measuring and sampling devices · CPC title

• C21C5/28 Primary

  Manufacture of steel in the converter {(C21C5/005 takes precedence)} · CPC title

• C21C2005/5288

  Measuring or sampling devices · CPC title

• C21C7/00 Primary

  Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00 (treating molten metals during moulding B22D1/00, B22D27/00) · CPC title