Use of ladle furnace slag from al-killed steel in si-killed steelmaking as calcium aluminate flux

Patent metadata

Field	Value
Publication number	US-2016333431-A1
Application number	US-201515111100-A
Country	US
Kind code	A1
Filing date	Jan 28, 2015
Priority date	Jan 31, 2014
Publication date	Nov 17, 2016
Grant date	—

Abstract

The present disclosures and inventions relate to a method for producing Si-killed steel comprising: a) supplying Al-killed steel ladle furnace slag; and b) adding the Al-killed steel ladle furnace slag to a Si-killed steel process to thereby produce Si-killed steel.

First claim

1 . A method for producing Si-killed steel comprising:
a) supplying Al-killed steel ladle furnace slag; and b) adding the Al-killed steel ladle furnace slag to a Si-killed steel process to thereby produce Si-killed steel.

2 . The method according to claim 1 , wherein the Al-killed steel ladle furnace slag comprises silica dioxide in an amount ranging from 1 wt % to 15 wt %, based on the total weight percentage of the Al-killed steel ladle furnace slag.

3 . The method according to claim 1 , wherein the Al-killed steel ladle furnace slag comprises silica dioxide in an amount ranging from 1 wt % to 8 wt %, based on the total weight percentage of the Al-killed steel ladle furnace slag.

4 . The method according to claim 1 , wherein the Al-killed steel ladle furnace slag comprises aluminum oxide in an amount ranging from 15 wt % to 50 wt %, based on the total weight percentage of the Al-killed steel ladle furnace slag.

5 . The method according to claim 1 , wherein the Al-killed steel ladle furnace slag comprises aluminum oxide in an amount ranging from 25 wt % to 45 wt %, based on the total weight percentage of the Al-killed steel ladle furnace slag.

6 . The method according to claim 1 , wherein the method does not comprise adding calcium fluoride.

7 . The method according to claim 1 , wherein the Al-killed steel ladle furnace slag has an oxygen potential equilibrium ranging from 1 ppm to 20 ppm.

8 . The method according to claim 1 , wherein the Al-killed steel ladle furnace slag comprises lime in an amount ranging from 40% by weight to 80% by weight based on the total Al-killed steel ladle furnace slag.

9 . The method according to claim 1 , wherein the Al-killed steel ladle furnace slag is added at a ladle step.

10 . The method according to claim 9 , wherein the ladle step comprises a tapping step.

11 . The method according to claim 10 , wherein the ladle step has a residence time in an amount ranging from 25 minutes to 50 minutes after the tapping step.

12 . The method according to claim 9 , wherein the method comprises a billet caster step after the ladle step.

13 . The method according to claim 9 , wherein the ladle step comprises desulfurization of the Al-killed steel ladle furnace slag.

14 . The method according to claim 1 , wherein step (b) comprises adding the Al-killed steel ladle furnace slag to a ladle, wherein the ladle is at a temperature ranging from 1500° C. to 1700° C.

15 . The method according to claim 1 , wherein the method does not comprise a slab casting step or adding calcium aluminate synthetic slag, or both.

16 . (canceled)

17 . An article of manufacture comprising Si-killed steel produced using Al-killed steel ladle furnace slag, wherein the article is a long product.

18 . The article of manufacture according to claim 17 , wherein the long product comprises a bar, a rod, a wire, or a beam.

19 . The article of manufacture according to claim 17 , wherein the long product does not comprise a flat product.

20 . A method for producing Si-killed steel comprising:
a) supplying Al-killed steel ladle furnace slag comprising silica dioxide in an amount ranging from 1 wt % to 8 wt %, based on the total weight percentage of the Al-killed steel ladle furnace slag and aluminum oxide in an amount ranging from 15 wt % to 50 wt %, based on the total weight percentage of the Al-killed steel ladle furnace slag; b) adding the Al-killed steel ladle furnace slag to a Si-killed steel process to thereby produce Si-killed steel; wherein the Al-killed steel ladle furnace slag is added at a ladle step, wherein the ladle step is at a temperature ranging from 1500° C. to 1700° C.; and wherein the method comprises a billet caster step after the ladle step.

21 . The product formed from the method of claim 1 .

Assignees

• Saudi Basic Ind Corp

Inventors

• Behera Narottam

Classifications

• B22D7/00

  Casting ingots, {e.g. from ferrous metals}(equipment for conveying molten metal B22D35/00) · CPC title

• C21C7/0075

  Treating in a ladle furnace, e.g. up-/reheating of molten steel within the ladle · CPC title

• C21C7/076 Primary

  Use of slags or fluxes as treating agents (C21C7/06, C21C7/064, C21C7/068 take precedence) · CPC title

• C21C7/0087

  Treatment of slags covering the steel bath, e.g. for separating slag from the molten metal · CPC title

• Y02P10/20

  Recycling · CPC title