Steel making method

A process for producing ferrous metal products from an ore containing iron oxides, said process comprising:

• (a) melting fluxing agents and the iron oxide ore together in a first zone to form a molten slag;
• (b) allowing said molten slag to stratify whereby iron oxide-rich slag collects at the bottom of said first zone;
• (c) transferring said iron oxide-rich slag to a second zone;
• (d) injecting coal and air into said second zone to form carbon monoxide and to reduce the iron oxides to form a molten ferrous metal product;
• (e) transferring off-gas from said second zone containing carbon monoxide to said first zone and combusting said off-gas with air in said first zone;
• (f) removing slag from at least one of said first and second zones and collecting said removed slag as a pool of molten slag;
• and
• (g) passing the air to at least one of said first and second zones through said pool of molten slag to preheat said air.

In a metalurgical process for the separation of metal values from a raw material into a molten slag phase utilizing air as a reactant, the improvement comprising:

• collecting molten slag from the process into a pool of molten slag divided into first and second zones;
• continuously circulating the slag between said first and second zones;
• passing the air to the process through said second zone of said pool to preheat the air;
• and
• collecting hot flue gas from the metalurgical process and passing said flue gas through the molten slag in said first zone, thereby continuously heating the slag pool.

A process for producing ferrous metal products from an ore containing iron oxides, said process comprising:

• (a) melting fluxing agents and the iron oxide ore together in a first zone to form a molten slag;
• (b) allowing said molten slag to stratify whereby iron oxide-rich slag collects at the bottom of said first zone;
• (c) transferring sid iron oxide-rich slag to a second zone;
• (d) injecting coal and air into said second zone to form carbon monoxide and to reduce the iron oxides to form a molten ferrous metal product;
• (e) transferring off-gas from said second zone containing carbon monoxide to said first zone and combusting said off-gas with air in said first zone;
• (f) collecting the molten iron or still metal product at the bottom of said second zone and transferring said metal product to a third zone;
• (g) contacting the molten metal product in said third zone with oxygen or air to reduce the carbon content;
• (h) holding the metal from said third zone in a quiescent fourth zone to allow residual slag and gas impurities to separate;
• (i) injecting the molten metal from said fourth zone into a reactive molten slag in a fifth zone for further purification;
• and
• (j) atomizing the molten metal from said fifth zone in the presence of an inert gas to wash out residual dissolved gas.

A process for producing ferrous metal products from an ore containing iron oxides, said process comprising:

• (a) melting fluxing agents in a cylindrical furnace to form a cylindrical body of molten slag, said body being in communication with a gas space above its upper surface;
• (b) injecting air and coal into a lower portion of said body of molten slag to establish reducing conditions and a reducing zone;
• and
• (c) injecting additional air into an upper portion of said body of molten slag from a plurality of points surrounding the circumference of said body of molten slag to establish oxidizing conditions and a melting zone, said coal reacting with air in said reducing zone to form carbon monoxide which circulates into said melting zone for reaction with said additional air, said air injection into said melting zone creating a flow pattern of molten slag moving radially toward the center of said body, said radially moving molten slag becoming densified as it releases gas into the gas space above said melting zone, and said densified slag circulating downwardly through the center of said slag body and into said reducing zone.