Abstract: A method and an apparatus for the gaseous reduction of particulate iron ores is disclosed, wherein the reduced ore, commonly called DRI (Direct Reduced Iron) or sponge iron, is treated in a vertical shaft moving bed furnace and discharged from said furnace in solid particulate form at high temperature, e.g. above 500.degree. C. The shaft furnace is of the type wherein a bed of particles descends by gravity through said furnace which has an upper section where ore pellets, lumps, or the like are reduced by reaction with a hot reducing gas, and a lower section of a downwardly tapering, preferably, in a generally conical shape, which converges to an outlet discharge orifice of smaller cross sectional area than the rest of said furnace.

Abstract: Brass, bronze and other mixture of copper and zinc use used to treat alkanolamine solutions used in systems for separating CO.sub.2 from gaseous mixtures to give enhanced protection against ferrous metal corrosion.

Abstract: A valve for controlling the flow of particulate solid material, especially a hot, friable, granular material. The valve comprises a fixed vertical feed tube and a concavo-convex valve member mounted for rotation about an axis forming an obtuse angle with the axis of the feed tube. The rotatable valve member is positioned so that its dished inner surface confronts the lower end of the feed tube and is essentially perpendicular thereto to block flow of material through the valve when it is in its closed position. The rotatable member has one or more openings therein that can be positioned in registry with the bottom of the feed tube to open the valve and permit the solid material to flow therethrough.

Abstract: A process for the gaseous reduction of iron ore to sponge iron in a vertical shaft, moving bed reactor wherein a hot gaseous mixture of hydrogen and a carbon monoxide is used to reduce the ore. It has been found unnecessary to use the external catalytic reformer of prior art processes to reform the methane and other hydrocarbon constituents of the natural gas commonly used as a source of gaseous reductants. By establishing a reducing gas recycle loop to which make-up natural gas and steam are fed in the proper proportions, the product sponge iron in the reactor can be used to catalyze hydrocarbon reformation, provided that the carbon content of the recycled gas is maintained low by removing carbon dioxide therefrom. Where pure methane is employed, steam/methane molar ratios within the preferred range of 1.4:1 to 2.2:1 are used.

Abstract: A water cooling panel forms a part of or substitute for the wall of a metallurgical furnace, such as an electric arc furnace. The panel can be formed alternately as a tube type cooler formed of parallel pipes connected at its ends in headers, with the latter having internal baffles to define a serpentine path, or as a box type cooler formed of steel plates or sheet and having internal baffle plates defining a serpentine path for the cooling fluid. In either case, fluid orificies are provided to permit a minor amount of flow through the baffles or baffle plates where there is a direction change in the serpentine flow path. This serves to prevent stagnation, and prevent the problems of hot spots and steam bubbles where there is a change of direction in the cooling flow. Projections welded along the furnace-facing side of the panel permit the panel to be covered with a layer of refractory material or solidified slag.

Abstract: A method for the desulfurization of sour natural gas containing sulfur contaminants wherein the natural gas is first heated to a temperature in the range of 250.degree. C. to 450.degree. C. and then contacted with a bed of sponge iron to remove at least a portion of the sulfur contaminants to form a sweet natural gas.

Abstract: A method of operating a vertical moving bed reduction reactor for reducing iron ore to sponge iron and having a reduction zone in the upper portion thereof and a cooling zone in the lower portion thereof to obtain a desired degree of metallization of the reduced ore in said reduction zone and a desired degree of carburization in said cooling zone which comprises supplying to said reactor a predetermined flow of reducing gas comprising carbon monoxide and hydrogen and, varying the ratio of reducing gas flow to said reduction zone to the reducing gas flow to said cooling zone to vary at least one of the amount of metallization attained in said reduction zone and the amount of carburization attained in said cooling zone, maintaining the carbon dioxide concentration in said reduction zone at a value which yields the desired degree of metallization therein and maintaining the carbon dioxide concentration in said cooling zone at a value which yields the desired degree of carburization in said cooling zone.

Abstract: Particulate iron ore is reduced to sponge iron in a vertical shaft reduction reactor by forcing the ore upwardly in a moving bed counter-current to a descending stream of hot reducing gas produced by the gasification of coal in a gasifier, for example, a melter-gasifier, containing a molten iron bath and producing a hot dust-laden gas. The product sponge iron may be used as a feed material for the molten bath in the gasifier. The reactor is equipped with a gas outlet plenum containing a renewable body of ore to minimize clogging at the gas outlet.

Abstract: The present invention relates to a process for the production of metallic iron through direct reduction of iron ores and particularly to an optimized process which permits operation at higher reducing temperatures with minimized problems of sinterization and agglomeration of iron ore particles. It is also an object of the present invention to provide a process wherein the required size of the reducing gas generating unit is reduced. Both objects are preferably achieved by means of injecting only natural gas, or a similar methane-containing gas into the cooling loop of the direct reduction process and venting a portion of the cooling gas from the cooling zone to the reducing zone (preferably, on the order of 1% to 2% of the methane content of the cooling gas in relation to the volume flow of the reducing gas).

Abstract: A process for the gaseous reduction of iron ore to sponge iron in a vertical shaft, moving bed reactor wherein a hot gaseous mixture of hydrogen and a carbon monoxide is used to reduce the ore. It has been found unnecessary to use the external catalytic reformer of prior art processes to reform the methane and other hydrocarbon constituents of the natural gas commonly used as a source of gaseous reductants. By establishing a reducing gas recycle loop to which make-up natural gas and steam are fed in the proper proportions, the product sponge iron in the reactor can be used to catalyze hydrocarbon reformation, provided that the carbon content of the recycled gas is maintained low by removing carbon dioxide therefrom. Where pure methane is employed, steam/methane molar ratios within the preferred range of 1.4:1 to 2.2:1 are used.

Abstract: A double valve assembly for regulating the feed of particulate material to or from a pressure vessel comprises a valve casing containing a flow-regulating valve and pressure sealing valve in series. Particulate material is fed to the valve assembly through a feed tube located at the top of the casing. The flow-regulating valve comprises a dish-shaped valve member swingable from a first position wherein it confronts the bottom of the feed tube and blocks flow of material therethrough to a second position at one side of the feed tube. The bottom of the feed tube is constructed and arranged to guide the particulate material away from the second valve position and thereby facilitate swinging movement of the swingable member from its first to its second position.

Abstract: An arrangement for charging an electric arc furnace with a relatively free-flowing charge of sponge iron or other iron-containing particles distributes the charge of particles within the furnace through a first chute before a melting stage of an electric arc steelmaking operation is begun, and then continuously through a second chute which extends through the roof of the furnace during the melting stage. The first chute extends from a hopper containing the sponge iron and can be moved when the roof is open to feed the charge into the furnace. A distributor cone at the lower end of this chute distributes the sponge iron in a predetermined pattern. A second chute affixed to the furnace roof and in communication therethrough with the interior of the furnace permits continuous charging of the furnace during operation.

Abstract: Apparatus for breaking apart agglomerations of particulate matter flowing in a vessel (particularly useful ina pressurized moving-bed vertical-shaft reduction reactor for the production of sponge iron) is exemplified by an externally mounted hydraulic cylinder having access to the interior of said vessel through a probe port, the piston of said hydraulic cylinder being provided with a conical probe positioned so as to be normally retracted out from the interior of said vessel but extendable by said hydraulic cylinder into and across the interior of said vessel, preferably at the narrowed discharge portion thereof, whereby said probe is angled to extend downwardly in the direction of flow of said particulate matter as well as across said flow to engage and break up any agglomerations of particulate matter in its path.

Abstract: A method is disclosed for achieving improved reduction efficiency and economy in the reduction of particulate metal ores, e.g. iron ore, in a vertical shaft, moving bed reactor having a reduction zone in which a heated reducing gas is caused to flow through a portion of the ore bed to reduce the metal ore thereof to metal; e.g. sponge iron. The improved efficiency and economy is achieved through an integrated reduction system in which a conventional reformer is used without the need to upgrade the reformed gas prior to feeding it directly to the reduction reactor as a reducing gas.

Abstract: A rotary valve adapted to be used in regulating the flow of a particulate material comprises a casing with inlet and outlet conduits and a rotor mounted for rotation about a horizontal axis in the casing. The rotor has a ring of partially closed pockets to meter the particulate material passing through the valve and its periphery is spaced inwardly from the interior of the casing an amount sufficient to prevent squeezing and disintegration of the particulate material between the rotor and inlet conduit. A baffle prevents particulate material from flowing downwardly in the space between the rotor and casing at the up-turning of the rotor.

Abstract: A rotary valve adapted to be used in regulating the flow of a particulate material comprises a casing with inlet and outlet conduits and a rotor mounted for rotation about a horizontal axis in the casing. The rotor has a ring of open and closed pockets to meter the particulate material passing through the valve and its periphery is spaced inwardly from the interior of the casing an amount sufficient to prevent squeezing and disintegration of the particulate material between the rotor and inlet conduit. A baffle structure is provided to prevent particulate material from flowing downwardly in the space between the rotor and casing at the up-turning of the rotor.

Abstract: Improved operation of the broadly known combination of a moving bed, gaseous reduction reactor for reducing iron ore and a melter-gasifier for converting to molten metal the sponge iron pellets produced in such a reactor is achieved by preparing a mixture of finely ground sponge iron and coal, either by mixing the sponge iron and coal and then grinding or by separately grinding the sponge iron and coal and then mixing, and feeding the mixture of finely ground coal and sponge iron, along with elemental oxygen, to a point below the surface of a molten metal bath within the melter-gasifier.

Abstract: Sponge iron pellets are protected against re-oxidation by pre-wetting them with water or steam, coating them with a pulverulent passivating agent which is a mixture of iron oxide particles and hydraulic cement particles, then drying the treated pellets. Especially good results are achieved by using a hydraulic cement such as Portland cement and an iron oxide/cement ratio of 40:60 to 70:30.

Abstract: A method for the batchwise reduction of iron ore to sponge iron in a multiple unit reactor system is disclosed in which (a) separate fixed beds of iron-bearing material are simultaneously treated in at least one cooling reactor and at least two reduction reactors, (b) a reducing gas composed largely of carbon monoxide and hydrogen is used to cool the iron-bearing material in said cooling reactor and thereafter to reduce the iron-bearing material in said reduction reactors, (c) a stream of said reducing gas is caused to pass through the fixed bed of iron ore in said cooling reactor and then cooled and (d) a portion of the cooled effluent reducing gas from said cooling reactor is recycled thereto, the improvement which comprises causing the remainder of the cooling reactor effluent gas to be fed to said reduction reactors and to flow in parallel through the fixed beds of metal-bearing material in said reduction reactors, and heating the reducing gas fed to said reduction reactors before it enters said reactors

Abstract: Process and apparatus for the gaseous direct reduction of iron ores wherein at least a portion of the spent reducing gas effluent from a reduction reactor is upgraded and thereafter heated and recycled to said reactor forming a reducing gas loop and make-up reducing gas is added to said loop. The hot products of combustion, i.e., flue gases, in the reformer are used to heat the recycled gas (and optionally the quenched make-up gas) while maintaining independent control of the operating conditions of the reformer and gas heater to give improved thermal efficiency and fuel savings. The reformer has a stand-by stack through which the reformer flue gas is directed when the gas heater is shut down (to permit independent continuous operation of the reformer).