Method and system for predicting addition amount of slagging lime during lf refining, and lf refining method

Patent metadata

Field	Value
Publication number	US-2022145413-A1
Application number	US-202117478880-A
Country	US
Kind code	A1
Filing date	Sep 18, 2021
Priority date	Nov 10, 2020
Publication date	May 12, 2022
Grant date	—

Abstract

A method and system for predicting an addition amount of slagging lime during ladle furnace (LF) refining, and an LF refining method are provided. The method includes: S1: calculating an actual sulfur distribution ratio in combination with a Kungliga Tekniska Högskolan (KTH) model and a least square method by using LF refining parameters; S2: calculating, according to a principle of sulfur mass conservation, a mass of final slag by using the LF refining parameters and the actual sulfur distribution ratio obtained in S1; and S3: calculating, according to a principle of material conservation during LF refining, an addition amount of slagging lime during the LF refining by using the LF refining parameters and the mass of the final slag obtained in S2, thereby predicting the addition amount of the required slagging lime.

First claim

1 . (canceled)

2 . A system for predicting an addition amount of a slagging lime during a ladle furnace (LF) refining, wherein the system comprises:
an actual sulfur distribution ratio calculation module, configured to calculate an actual sulfur distribution ratio in combination with a Kungliga Tekniska Högskolan (KTH) model and a least square method by using LF refining parameters, wherein the LF refining parameters comprise a mass percent of each component in a target slag and a mass percent of each component in a target molten steel during LF refining; a final slag mass calculation module, configured to calculate a mass of a final slag according to a principle of sulfur mass conservation by using the LF refining parameters and the actual sulfur distribution ratio; and a lime addition amount prediction module, configured to calculate, according to a principle of material conservation during the LF refining, the addition amount of the slagging lime during the LF refining by using the LF refining parameters and a mass of a final slag, thereby predicting the addition amount of the slagging lime, wherein the mass of the final slag is obtained by using the LF refining parameters and the actual sulfur distribution ratio; wherein the system uses a method for predicting the addition amount of the slagging lime during the ladle furnace (LF) refining, comprising: calculating the actual sulfur distribution ratio in combination with the Kungliga Tekniska Högskolan (KTH) model and the least square method by using the LF refining parameters; calculating the mass of the final slag by using the LF refining parameters and the actual sulfur distribution ratio; and calculating the addition amount of the slagging lime during the LF refining by using the LF refining parameters and the mass of the final slag, thereby predicting the addition amount of the slagging lime; the actual sulfur distribution ratio is calculated with the following steps: defining a formula for a sulfur distribution ratio, as shown in Formula (1):

L
S

=

w
⁡

(
S
)

w
⁡

[
S
]

,

(
1
)

wherein, w[S] denotes a mass percent of sulfur in a molten steel, in unit of %; w(S) denotes a mass percent of sulfur in a slag, in unit of %; and L S denotes the sulfur distribution ratio;
denoting a sulphide capacity with Formula (2) in the KTH model:

C
S

=

exp
⁢

{

-

Δ
⁢

⁢

G
θ

RT

}

·

{

a

o
2

f

s

2
-

}

=

exp
⁢

{

-

Δ
⁢

⁢

G
θ

RT

}

·
exp

⁢

{

-

ζ
RT

}

,

(
2
)

wherein, C s denotes the sulphide capacity; ΔG θ denotes Gibbs free energy and is indicated as ΔG θ =118535−58.8157·T, in unit of J/mol; R denotes gas constant and is 8.314 (J/mol·K): ζ denotes a function of a single component with respect to a temperature in case of no interaction between components; f s 2− denotes an activity coefficient of sulfur in the slag; and α o 2− denotes an activity of oxygen in the slag;
defining a relation between a steel-slag sulfur equilibrium distribution ratio L S ′ and Cs, as shown in Formula (3):

Assignees

• Univ Beijing Science & Technology

Inventors

• Liu Qing
• Xin Zicheng
• Zhang Jiangshan
• Zhang Junguo
• Zhang Chunhui

Classifications

• C21C2300/06

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

• C21C7/064 Primary

  Dephosphorising; Desulfurising · CPC title

• G06Q10/04

  Forecasting or optimisation specially adapted for administrative or management purposes, e.g. linear programming or "cutting stock problem" (market predictions or forecasting for commercial activities G06Q30/0202) · CPC title

• G06F30/20 Primary

  Design optimisation, verification or simulation (optimisation, verification or simulation of circuit designs G06F30/30) · CPC title

• Y02P10/25

  Process efficiency · CPC title