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

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.

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 .