MOLTEN STEEL TREATMENT DEVICE AND MOLTEN STEEL TREATMENT METHOD USING SAME

• US 20190309380A1
• Filed: 10/30/2017
• Published: 10/10/2019
• Est. Priority Date: 11/01/2016
• Status: Abandoned Application

• Current Assignee: Posco Holdings Incorporated
• Original Assignee: Posco Holdings Incorporated
• Inventors: KIM, Wook
• Application Number:
  US16/345,522
• Publication Number:
  US 20190309380A1
• Time in Patent Office: Days
• CPC Class Codes: C21C 7/0075 Treating in a ladle furnace, e.g. up-/reheating of molten steel within the ladle
• CPC Class Codes: C21C 7/0087 Treatment of slags covering the steel bath, e.g. for separating slag from the molten metal
• CPC Class Codes: C21C 7/064 Dephosphorising; Desulfurising

Abstract

Provided is a molten steel treatment device and a molten steel treatment method using same. The molten steel treatment method may include: preparing slag on molten steel; contacting a first electrode to at least a portion of the slag and a second electrode to at least a portion of the molten steel; and polarizing the slag by applying a voltage to the first electrode and the second electrode, to easily remove inclusions and impurity elements in the molten steel by controlling basicity and oxidation degree of the slag without using separate additives.

Claims

1. A molten steel treatment device, which is used for ladle refining, comprising:

power supply module comprising a first electrode, a second electrode, and an insulator provided between the first electrode and the second electrode to electrically separate the first electrode from the second electrode; and

a power unit connected to the power supply module,

wherein the first electrode has a plate shape having an area,

the second electrode vertically extends while passing through the first electrode, and

an insulator is provided between the first electrode and the second electrode.

2. The molten steel treatment device of claim 1, wherein an extension part, which has an area and is disposed in parallel to the first electrode, is provided to a lower portion of the second electrode

an insulator is provided between the first electrode and the second electrode.

3. The molten steel treatment device of claim 2, wherein the first electrode comprises a material having a specific gravity less than that of the slag provided on molten steel.

4. The molten steel treatment device of claim 3, wherein the first electrode comprises graphite, and the second electrode comprises a conductive refractory material containing Al₂O₃(MgO)—

C

an insulator is provided between the first electrode and the second electrode to space the first electrode from the second electrode.

5. The molten steel treatment device of claim 1, wherein the power supply module is installed on a ladle cover so that the first electrode and a portion of the second electrode are inserted into a ladle.

6. A molten steel treatment device, which is used for ladle refining, comprising:

a power supply module comprising a first electrode, a second electrode, and an insulator provided between the first electrode and the second electrode to electrically separate the first electrode from the second electrode; and

a power unit connected to the power supply module,

wherein each of the first electrode and the second electrode has a plate shape having an area, and

the insulator has a length greater than a thickness of slag provided on the molten steel.

7. The molten steel treatment device of claim 6, wherein the first electrode comprises a material having a specific gravity less than that of the slag provided on molten steel.

8. The molten steel treatment device of claim 7, wherein the second electrode comprises a conductive refractory material containing Al₂O₃(MgO)—

C.

9. The molten steel treatment device of claim 6, wherein the power supply module is installed on a ladle cover so that the first electrode and a portion of the second electrode are inserted into a ladle.

10. A molten steel treatment method comprising:

preparing slag on molten steel;

contacting a first electrode to at least a portion of the slag and a second electrode to at least a portion of the molten steel; and

polarizing the slag by applying a voltage to the first electrode and the second electrode.

11. The molten steel treatment method of claim 10, wherein the first electrode floats on the slag, and at least a portion of the second electrode is dipped into the molten steel.

12. The molten steel treatment method of claim 11, wherein in the polarizing of the slag, the first electrode is connected to a positive electrode, and the second electrode is connected to a negative electrode.

13. The molten steel treatment method of claim 12, wherein the first electrode comprises graphite, and

in the polarizing of the slag, oxygen ions in the slag react with the first electrode and are removed in a form of a CO gas.

14. The molten steel treatment method of claim 13, wherein Ca elements in the slag are reduced by being introduced into the molten steel.

15. The molten steel treatment method of claim 14, wherein the Ca elements react with sulfur elements in the molten steel to produce CaS.

16. The molten steel treatment method of claim 15, wherein the CaS is collected to the slag.