Molten iron refining method and device thereof

Patent metadata

Field	Value
Publication number	US-10077482-B2
Application number	US-201314910771-A
Country	US
Kind code	B2
Filing date	Sep 25, 2013
Priority date	Aug 7, 2013
Publication date	Sep 18, 2018
Grant date	Sep 18, 2018

Abstract

Provided are a molten metal refining device and method. The molten metal refining method includes: preparing molten metal; dipping an impeller into the molten metal; supplying a liquid dephosphorization agent on top of the molten metal; and stirring the molten metal by rotating the impeller, wherein a solid dephosphorization agent in a powder state is supplied through the lower portion of the impeller in the stirring of the molten metal, thereby improving the stirring efficiency of the molten metal and efficiently controlling the phosphorus concentration in the molten metal.

First claim

What is claimed is:

1. A method of refining molten metal, the method comprising:
preparing molten metal;
removing slag from the molten metal;
dipping an impeller into the molten metal;
supplying a liquid dephosphorization agent to an upper portion of the molten metal; and
stirring the molten metal by rotating the impeller,
wherein a solid dephosphorization agent in a powder state is supplied through a lower portion of the impeller during the stirring of the molten metal, and
wherein in the dipping of the impeller, blades of the impeller are disposed above a midpoint of a total depth of the molten metal, and blowing nozzles of the impeller are disposed under the midpoint of the total depth of the molten metal.

2. The method of claim 1 , wherein the blades of the impeller are disposed in a region of 10% to 30% from a molten metal surface of the molten metal.

3. The method of claim 1 , wherein the stirring comprises: stirring the molten metal such that a direction of a stirring flow of the molten metal generated from blades of the impeller coincides with a direction of a stirring flow of the molten metal generated by the solid dephosphorization agent blown into the molten metal.

4. The method of claim 3 , wherein the stirring flow generated from the blades flows to be separated into upward and downward directions, and an area of the stirring flow of the molten metal in the downward direction from the blades is greater than an area of the stirring flow of the molten metal in the upward direction from the blades.

5. The method of claim 1 , wherein the liquid dephosphorization agent supplied to the molten metal is 50 wt % to 70 wt % with respect to a total weight of the liquid and solid dephosphorization agents.

6. The method of claim 5 , wherein an inert gas is supplied together with the solid dephosphorization agent.

7. The method of claim 6 , wherein the slag is removed after the stirring of the molten metal.

8. A method of refining molten metal, the method comprising:
preparing molten metal;
dipping an impeller into the molten metal;
supplying a liquid dephosphorization agent to an upper portion of the molten metal; and
stirring the molten metal by rotating the impeller,
wherein a solid dephosphorization agent in a powder state is supplied through a lower portion of the impeller during the stirring of the molten metal, and
wherein the liquid dephosphorization agent supplied to the molten metal is 50 wt % to 70 wt % with respect to a total weight of the liquid and solid dephosphorization agents.

9. The method of claim 8 , wherein an inert gas is supplied together with the solid dephosphorization agent.

10. The method of claim 8 , wherein slag is removed after the stirring of the molten metal.

11. The method of claim 8 , wherein slag is removed before the dipping of the impeller.

12. The method of claim 8 , wherein in the dipping of the impeller, blades of the impeller are disposed above a midpoint of a total depth of the molten metal, and blowing nozzles of the impeller are disposed under the midpoint of the total depth of the molten metal.

13. The method of claim 12 , wherein the blades of the impeller are disposed in a region of 10% to 30% from a molten metal surface of the molten metal.

14. The method of claim 8 , wherein the stirring comprises: stirring the molten metal such that a direction of a stirring flow of the molten metal generated from blades of the impeller coincides with a direction of a stirring flow of the molten metal generated by the solid dephosphorization agent blown into the molten metal.

15. The method of claim 14 , wherein the stirring flow generated from the blades flows to be separated into upward and downward directions, and an area of the stirring flow of the molten metal in the downward direction from the blades is greater than an area of the stirring flow of the molten metal in the upward direction from the blades.

Assignees

• Posco

Inventors

• Park Jung Ho
• Kang Soo Chang
• Chun Jin Kyu
• Seo Yun Yeol

Classifications

• F27D27/00

  Stirring devices for molten material (charging or discharging liquid or molten material F27D3/14) · CPC title

• C21C1/02 Primary

  Dephosphorising or desulfurising · CPC title

• C21C1/06

  Constructional features of mixers for pig-iron · CPC title

• C21C1/025

  Agents used for dephosphorising or desulfurising · CPC title

• C21C7/0645

  Agents used for dephosphorising or desulfurising · CPC title