Agent for steel-making formed by aluminum-making slag

Abstract

The present invention discloses an agent for steel-making formed by aluminum-making slag, which is used by adding to molten steel, wherein said agent comprises: metal aluminum, aluminum oxide, silicon dioxide, magnesium oxide, and calcium oxide. Said agent for steel-making is a deoxidizing agent, modifying agent, and slag regulating agent for steel-making. Said deoxidizing agent or modifying agent for steel-making may comprise by mass percentage 25-70% Al, 3-30% Al 2 O 3 , 10-30% CaO, 5-15% MgO, 3˜10% SiO 2 , and a small amount of impurities. Said slag regulating agent for steel-making may comprise by mass percentage 5-20% Al, 25-70% Al 2 O 3 , 10-50% CaO, 5-15% MgO, 3˜10% SiO 2 , and a small amount of impurities. The agent for steel-making of the present invention facilitates removing sulfur and other impurities from molten steel. In addition, the greatest advantage of this product lies in that it is capable of decreasing total cost of steel-making and improving efficiency of steel-making.

1 . An agent for steel-making formed by aluminum-making slag, which is used by adding to molten steel, wherein said agent comprises: metal aluminum, aluminum oxide, silicon dioxide, magnesium oxide, and calcium oxide. 
     
     
         2 . The agent for steel-making according to  claim 1 , wherein said agent for steel-making is a deoxidizing agent for steel-making. 
     
     
         3 . The agent for steel-making according to  claim 1 , wherein said agent for steel-making is a modifying agent for steel-making. 
     
     
         4 . The agent for steel-making according to  claim 1 , wherein said agent for steel-making is slag regulating agent for steel-making. 
     
     
         5 . The agent for steel-making according to  claim 2  or  3 , wherein said deoxidizing agent or modifying agent for steel-making comprises by mass percentage 25-70% Al, 3-30% Al 2 O 3 , 10-30% CaO, 5-15% MgO, 3˜10% SiO 2 , and a small amount of impurities. 
     
     
         6 . The agent for steel-making according to  claim 5 , wherein said deoxidizing agent or modifying agent for steel-making consists of the following compositions by mass percentage: 25-70% Al, 3-30% Al 2 O 3 , 10-30% CaO, 5-15% MgO, 3˜10% SiO 2 , <3% rare earth elements, and a small amount of impurities. 
     
     
         7 . The agent for steel-making according to  claim 6 , wherein each composition in said deoxidizing agent or modifying agent for steel-making is powdered shaped, with a granularity of 50 μm˜1 mm. 
     
     
         8 . The agent for steel-making according to  claim 7 , wherein said deoxidizing agent or modifying agent powder for steel-making is pressed into a sphere shape. 
     
     
         9 . The agent for steel-making according to  claim 8 , wherein said deoxidizing agent or modifying agent powder for steel-making, which has been pressed into a sphere shape, has a diameter of 20˜50 mm 
     
     
         10 . The agent for steel-making according to  claim 7  or  8 , wherein said deoxidizing agent or modifying agent for steel-making is added to the molten steel during molten steel tapping in primary melting of a converter or electric furnace. 
     
     
         11 . The agent for steel-making according to  claim 7  or  8 , wherein said deoxidizing agent or modifying agent for steel-making is added to a ladle refining furnace or electric furnace. 
     
     
         12 . The agent for steel-making according to  claim 4 , wherein said slag regulating agent for steel-making comprises by mass percentage 5-20% Al, 25-70% Al 2 O 3 , 10-50% CaO, 5-15% MgO, 3˜10% SiO 2 , and a small amount of impurities. 
     
     
         13 . The agent for steel-making according to  claim 12 , wherein said slag regulating agent for steel-making consists of the following compositions by mass percentage: 5-20% Al, 25-70% Al 2 O 3 , 10-50% CaO, 5-15% MgO, <3% rare earth elements, 3˜10% SiO 2 , and a small amount of impurities. 
     
     
         14 . The agent for steel-making according to  claim 13 , wherein each composition in said slag regulating agent for steel-making is powdered shaped or is sphere shaped by pressing powders. 
     
     
         15 . The agent for steel-making according to  claim 14 , wherein said slag regulating agent for steel-making is added to a ladle refining furnace for slag regulating, or is added to molten steel for slag regulating during molten steel tapping in primary melting of a converter or electric furnace. 
     
     
         16 . The agent for steel-making according to  claim 11 , wherein said deoxidizing agent or modifying agent powder for steel-making is blown into a ladle refining furnace or electric furnace. 
     
     
         17 . The agent for steel-making according to  claim 12 , wherein during steel tapping in a converter, said deoxidizing agent or modifying agent for steel-making is added once the addition of Fe alloys is complete. 
     
     
         18 . The agent for steel-making according to  claim 17 , wherein during steel tapping in the converter, when ⅓ of the steel has been tapped, ⅔ of the deoxidizing agent or modifying agent for steel-making is added, and then when the steel tapping is complete, the remaining ⅓ deoxidizing agent or modifying agent for steel-making is added to the surface of the ladle refining furnace. 
     
     
         19 . The agent for steel-making according to  claim 15 , wherein the dosage of said slag regulating agent for steel-making is selected so that MgO in the furnace slag reaches a saturation value.