Abstract: A pollution control system for electric arc furnaces includes fume collectors disposed at one side and above the furnace and pairs of blower nozzles mounted on an overhead crane used to deliver feed materials to the furnace. One nozzle of each pair is adjustable in a vertical plane and the other nozzle of each pair is adjustable in vertical and horizontal planes so that the nozzles may be positioned for blowing furnace fumes into the fume collectors when the furnace roof is elevated for charging, during furnace operation and when the furnace is tilted for tapping.

Abstract: An electric arc furnace having at least one electrode and a burner and first and second supply systems for respectively supplying an oxygen containing gas and fuel to the burner. An exhaust gas conduit is connected to the furnace and includes a first damper for controlling the flow rate of exhaust gases and a second damper for controlling the flow of dilution air into the exhaust conduit. First and second position sensors are coupled to the first and second dampers, respectively, for sensing the positions thereof, a temperature sensor is coupled to the exhaust conduit for sensing the temperature therein and a pressure sensor is coupled to the furnace for sensing the furnace pressure. A first control is coupled to the first supply system and to the temperature sensor and to the first position sensor for initiating and controlling the flow of oxygen containing gas in relation to the temperature in the conduit and the position of the first damper.

Abstract: A method of making steel having low levels of carbon, nitrogen, phosphorous and oxygen comprises the steps of vacuum reladling a ladle of low phosphorous steel for reducing carbon levels and separating the metal from a highly oxidizing slag, blowing oxygen into the metal contained in a teeming ladle at a vacuum pressure and simultaneously bubbling an inert gas through the metal for removing additional carbon and elevating the temperature of the metal, discontinuing the oxygen blow while maintaining the vacuum pressure and continuing the delivery of inert gas for removal of nitrogen. A desulphurizing agent may be delivered prior to the oxygen blow and alloying additions may be made as required.

Abstract: A method of preheating scrap metal with impure gases discharging from a metallurgical vessel includes the steps of conducting a first portion of the gases to a container of scrap metal, contacting the scrap metal with the gases for preheating the same whereby additional impurities are generated, withdrawing the impure gases after contact with the scrap metal and mixing the same with a second portion of impure gases from the metallurgical vessel, thermally cracking the mixture in a combustion chamber to remove impurities and thereafter removing particular matter from the gases prior to the discharge to the atmosphere.

Abstract: An iron free self baking electrode comprises an outer metallic shell, a center core formed of a graphite or prebaked carbon material spaced from the shell and a quantity of a carbonaceous paste which cures into a solid electrode and bonds to the graphite or prebaked carbon core as the core and paste passes downwardly through the casing. The graphite or prebaked carbon core conducts heat to the paste material to promote more rapid curing.

Abstract: A feed system for a smelting furnace having a plurality of feed chutes arranged in a spaced apart, circular array. The feed system includes a circular conveyor mounted adjacent the furnace and concentrically with the feed chutes. The conveyor also has a gap therein which permits the discharge of material downwardly into the feed chutes and means for rotating the conveyor about its axis of curvature to sequentially position the gap above successive feed chutes. In addition, one or more feed hoppers are positioned above the conveyor for depositing feed materials thereon.

Abstract: A system for removing hydrogen fluoride, finely divided solids and hydrocarbons from aluminum production process emissions includes a vertical scrubbing chamber of constant cross section for receiving the emissions, and an injector disposed axially within the scrubbing chamber for injecting finely divided alumina particles radially into the emission stream, and a filtering device for capturing the alumina particles and entrapping pollutants.

Abstract: A method of producing steel from ferrous hot metal containing carbon includes the steps of delivering oxygen and a surrounding sheath of hydrocarbon shielding fluid to the metal and beneath its surface to elevate the temperature to at least 1350.degree. C. Iron material taken from the group consisting of prereduced iron ore, prereduced iron pellets and iron ore or combinations thereof are then delivered to the metal at controlled rates. The rate of charging is balanced with the heat input to the bath, in order to maintain or increase the bath temperature. The heat input is supplied by the simultaneous injection of carbon and oxygen through bottom tuyeres. The rate of carbon injection is also regulated to maintain the carbon content in the bath at the desired level.

Abstract: A method and apparatus for preheating scrap metal within pure gases discharged from a metallurgical vessel. The method comprises the steps of burning the gases in a combustion chamber to remove impurities therefrom, conducting a first portion of the combustion products to a container of scrap metal, contacting the scrap metal with the combustion products for preheating the scrap metal whereby additional impurities are generated, washing in a wet scrubber the mixture of combustion products and additional impurities, mixing the scrubbed combustion products and additional impurities with a second portion of the combustion products from the combustion chamber, and removing particulates from the mixture.

Abstract: A damper assembly for use with the inlet duct of a pollution control system includes a plurality of vanes which are pivotally mounted for movement between an open position and a closed position wherein the vanes coact to close the duct. Each vane is pivotally mounted at one end on a closure plate releasably affixed over an opening sized to permit the vane to be removed therethrough. The vanes also include a hanger member receivable on a trolley rod which may be inserted into a second opening in the duct for supporting the vane after it has been disconnected from its pivot support and as it is being slid through the opening and into and out of position within the duct.

Abstract: A metallurgical vessel having an energy source and in which molten metal is contained for processing. A tuyere system is provided below the level of molten metal to permit the injection of gases, fluxes, ores, alloying additions and other materials to convert the molten metal to steel.

Abstract: A tuyere for use in a metallurgical vessel comprising a first pipe adapted to be affixed to the wall of a metallurgical vessel and having a first end extending through the refractory lining of the vessel and a second end extending outwardly therefrom. A gas inlet member is affixed to the second end of the pipe and the second pipe is affixed to the gas inlet member and extends inwardly through the first pipe. The outer diameter of the second pipe is smaller than the inner diameter of the first pipe to provide a gap there between. Means are provided between the first and second pipes to maintain them in spaced-apart relation and the interior of the first pipe is filled with a material such as refractory.

Abstract: A molten metal processing vessel is supported on a trunnion support by a plurality of upper and lower link members each having a pair of legs. One pair of link member legs are coupled to and are disposed between three hinge members affixed to the vessel. The other legs of the upper members are also pivotally connected to and disposed between three hinge members mounted atop the trunnion support and the other legs of the lower members are pivotally connected to and disposed between three hinge members mounted on an auxiliary ring disposed adjacent the lower end of the trunnion support. The gap between the legs which are coupled to the vessel is greater than those coupled to the trunnion support. The trunnion support includes a plurality of spring washers disposed between an auxiliary ring and a trunnion and are prestressed by a spring seat and tapered spring adjustment members.

Abstract: A metallurgical vessel includes a plurality of tuyeres for respectively delivering process materials to molten metal contained within the vessel. A first plurality of axial passages are provided in at least one vessel trunnion pin for conducting fluids to and from the vessel and a second plurality of radial passages are also formed in the trunnion pin and each respectively intersects one of the axial passages. An adapter sealingly engages the outer end of each radial passage and is retained in position by a common cover plate. The outer end of each adapter extends through the cover plate and is constructed and arranged for being coupled to one end of a conduit, the other end of which is connected to one of said tuyeres.

Abstract: A molten metal processing vessel is supported on a trunnion ring by a plurality of triangular members and adjustable links. Each triangular member is pivotally connected to the vessel to a clamp ring which engages the upper trunnion ring flange. The links are pivotally connected to the vessel and to a second clamp ring which engages the lower trunnion ring flange. A plurality of disk springs are disposed between the second clamp ring and the trunnion ring.

Abstract: An enclosure for a metallurgical vessel has a front access door to permit movement of charging devices into the enclosure for charging the metallurgical vessel disposed therein. A gas collector is mounted in the upper end of the enclosure, a first hood mounted in the enclosure for movement between an operative position above the vessel and an inoperative position remote from the vessel. When in its operative position, the hood is disposed in coupling engagement with one side of the gas collector. A second hood is fixedly coupled to the other side of the gas collector. Dampers are disposed between each hood and the gas collector.

Abstract: The device consists of a retractible tuyere which can be used with different types of steel melting furnaces, or any other metallurgical vessel. Said tuyere is introduced in the liquid steel bath to make the controlled refining of the same by means of gaseous oxygen injection with any other innert gas, generally argon.The retractible tuyere consists of two concentric pipes. Through the annular gap between the pipes a cooling gas or liquid fluid is injected, which is generally an hydrocarbon.Through the center pipe a refining gas mixture is injected. The system also consists of a cooled tuyere holding box and a fluid control and injection system.The tuyere is generally introduced through an opening made in the side wall of the furnace, in a way that the tip of the same is located below the liquid steel level. Due to the retractible characteristic of the tuyere, the same is introduced in the bath only during the time required by the process.

Abstract: A method of treating ferrous metal includes the steps of containing in a metallurgical vessel a quantity of ferrous metal which is at least partially solid in form, entraining finely divided carbon and a fluxing agent in a nonoxidizing gas and injecting the same in a first flow path and from beneath said metal, simultaneously injecting a first quantity of oxygen in a second flow path separate from said first flow path and beneath said metal for oxidizing the carbon to elevate the temperature of said metal. A second quantity of oxygen is injected into the metal in a third flow path and from above the metal for reducing the carbon content thereof. Additional fluxing agents may also be introduced from above the metal. After the desired metal temperature has been achieved, the delivery of carbon and fluxing agents through the first flow path is terminated while the flow of nonoxidizing gas is continued to promote mixing.

Abstract: A method of producing steel from ferrous hot metal containing carbon includes the steps of delivering oxygen and a surrounding sheath of hydrocarbon shielding fluid to the metal and beneath its surface to elevate the temperature to about 1350.degree. C. Pelletized iron material and carbon are then simultaneously delivered to the metal at controlled rates with the rate of carbon delivery being regulated so that the carbon level within the metal maintains in substantial equilibrium. After charging of the pellets has been completed, the delivery of carbon is terminated while the delivery of oxygen and hydrocarbon shielding fluid is continued until the metal carbon level is reduced a desired level.

Abstract: A steel conversion method includes the steps of delivering a first quantity of oxygen and a surrounding sheath of hydrocarbon shielding fluid beneath the level of a quantity of molten ferrous metal or bath contained in a vessel by means of bottom tuyeres and simultaneously delivering a second quantity of oxygen to the bath from above through a top lance. The oxygen delivered through the bottom tuyeres is sufficient to promote mixing and is about 10% to 40% of the oxygen required for oxidation of impurities with the balance delivered through the top lance. An additional quantity of oxygen is delivered through the top lance to the space above the bath for post-combustion of off-gases to increase the thermal energy in the bath. Fluxes such as lime are added from above in lump form in the conventional manner or are entrained in the upper oxygen stream as required.