Abstract: Apparatus for generating a reducing gas in a molten iron bath gasifier while simultaneously producing direct reduced iron oxide in an associated shaft furnace with the gas from the gasifier. The apparatus includes means for controlling the temperature of the reducing gas to the shaft furnace, means for cleaning, upgrading, and introducing spent top gas from the direct reduction furnace to the molten bath gasifier as a gaseous coolant to cool the reaction with the bath and reduce refractory wear within the gasifier.

Abstract: In a process for the direct production of sponge iron particles and liquid crude iron from iron ore in lump form, which is reduced in a direct reduction unit and fed in a hot condition to a melting gasifier, the sponge iron particles which are discharged from the direct reduction unit are separated into a fine grain fraction and a coarse grain fraction, and only the fine grain fraction is fed to the melting gasifier. That ensures economy of operation, without an excess of gas.

Abstract: Herein disclosed are both waste gas circulation method and system for effectively recovering waste heat from an on-strand type sintering apparatus which has its sintering and cooling zones extending continuously along a horizontal strand. The hottest waste gases coming from the final stage of the sintering zone and the front stage of the cooling zone, in which the sintering reaction of a charge mixture is completed, are subjected to heat recovery, and sulfur oxides in the hottest gases are prevented from condensing on the water pipe or pipes of a waste-heat boiler by preheating the water, which is supplied for the heat recovery, with the still hot waste gases coming from the downstream half of the cooling zone. The heat of the still hot waste gases are exchanged with cold water so that this water may be heated into hot water. On the other hand, the heat of the hottest gases is exchanged with steam so that this steam may be heated into superheated steam.

Abstract: In a melting/gasifying furnace including a coke-filled layer, coal is gasified by oxygen blown through tuyeres into a hot reducing gas which is caused to ascend through the coke-filled layer so as to melt reduced iron supported on the top of the coke-filled layer. The resulting molten iron flows down through the coke-filled layer, and is collected in the lowermost region of the coke-filled layer and discharged therefrom, while the hot gas is recovered. The thus recovered gas is fed into a shaft reduction furnace to reduce iron ores, and the thus formed reduced iron is supplied into the melting/gasifying furnace. In addition to the coal, a variety of fuels mainly comprising carbon and hydrogen such as heavy oil, natural gas, etc. are used for gasification. The fuel is blown through the tuyeres and/or charged through middle openings disposed above the tuyeres.

Abstract: A sintering machine for pulverulent ore concentrates containing sulfidic metals including an ignition zone, a sintering zone and at least two cooling zones wherein there is total recirculation of cooling gases between two cooling zones and including a recuperative heat exchanger for cooling the exhaust gas from the first cooling zone, prior to its introduction to the second cooling zone.

Abstract: Ores which include in combination iron oxide, cobalt oxide and nickel oxide are treated in a continuous shaft reduction furnace to selectively reduce nickel and cobalt to metallized form while leaving the iron oxide in the oxide form. Reacted top gas is recycled and mixed with partially combusted gasified fossil fuel in a combustion chamber to achieve the required concentration of reductants in the reducing gas. The cooling zone operates with a similar concentration of reductants in the cooling gas. Apparatus is also disclosed for carrying out the process.

Abstract: A melting furnace includes a crucible surrounded by a wall to form an annular heating chamber. A burner provides a long combustion flame which circulates through the annular chamber to heat the exterior of the crucible. The combustion flame and hot gases in this chamber are exhausted through a stack having a first exhaust port at the top of the stack and a second exhaust port on the side of the stack. A duct, connected to the stack at the second port, provides a path for ducting the combustion flame and gases into the mouth of the crucible to melt a charge therein.The first exhaust port is selectively opened and closed, as by a damper, to alternatively direct the combustion flame and gases either (a) through the first port to the atmosphere, or (b) through the second port, into the duct, and into the mouth of the crucible. When the first port is open, noxious fumes from the crucible are advantageously drawn through the duct and into the exhaust stack.

Abstract: Energy consumption may be minimized when reducing iron oxide with reducing gases which are at least partially re-circulated in the process and where the re-circulation gas is washed to remove the reaction product CO.sub.2 in what is known as a CO.sub.2 wash to enable it to be re-used, by the heat requirement necessary for regenerating the washing liquid in the CO.sub.2 wash being entirely or partially covered by the physical heat content in top gas from the shaft furnace and/or gas leaving the sponge-iron cooler of the shaft furnace.

Abstract: A process for preparing crude iron and energy-rich, gases, the raw materials being comprised of iron ore concentrate, carbon-containing materials, optionally oxygen gas and electric energy, comprising the combination of the following operations:1.1: preheating of the iron ore concentrate by means of combustion gases from the combustion of discharged gases from the prereduction according to 1.2 below;1.2: prereduction of the iron oxides of the concentrate preheated according to 1.1 by means of part of the discharged gases from the arc furnace according to 1.3 below;1.3: introduction of the concentrate prereduced according to 1.2 into the plasma zone below the electrode of an arc furnace, which contains a crude iron melt, the temperature of which is maintained above 1300.degree. C.

Abstract: Method and apparatus for smelting a sulfidic ore concentrate such as a copper concentrate in which the concentrate is smelted in an oxidizing atmosphere, the melt is after-treated with reducing gases from a plurality of lances which blow the reducing gases onto the melt in the form of concentrated streams of high kinetic energy and form a metal-rich phase and a slag phase. The improvement of the present invention is concerned with oxidizing the concentrate sufficiently to form an enriched metal matte containing more than 75% by weight metal at a throughput of more than 500 metric tons per day, the oxidizing being carried out in a smelting cyclone operating as a steam generator and at a sufficiently high temperature so that the heat transferred to the cyclone walls is at least 500,000 Kcal/sq. m. of cyclone wall/hr.

Abstract: In a direct reduction plant employing a shaft furnace for reducing iron ore and a steam reformer for producing a reducing gas from gaseous hydrocarbon compounds and provided with an installation for heating at least a part of the reducing gas to be supplied to said shaft furnace, either hydrogen sulfide or a material adapted to produce hydrogen sulfide within the reducing gas is added to the reducing gas system from outside of the system so that the concentration of hydrogen sulfide in the reducing gas at the inlet of said shaft furnace is 10 to 100 volume ppm.

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: A process for the direct reduction of iron ore in a shaft furnace having an upper reducing zone and a lower cooling zone in which reducing gas is introduced to the furnace at the bottom of the reducing zone around the periphery of the furnace, exhausted reducing gas or top gas is removed from the top of the furnace, cleaned, mixed with additional hydrocarbons, and reinjected into the furnace below the reducing zone. The hot reducing gas is injected serially into different sectors of the cross-section of the furnace and at varying velocities to force upflowing cleaned top gas to change its flow path or its flow rate, or both, periodically. Apparatus for accomplishing the method is also disclosed.

Abstract: A sintering plant of the type sintering raw materials, such as pulverized ores, while transporting them with a conveyor, in which quicklime is fed to the lower layer of the raw materials on the conveyor so that SO.sub.x produced during sintering process may be mainly contained in gases discharged to the downstream half of wind box array disposed below the conveyor and the gases only from the downstream half are fed through a heat exchanger to a desulfurization equipment having a relatively low capacity. The heat exchanger is arranged to heat water to be fed to a device, such as waste heat boiler, adapted to be operated with thermal energy recovered from a cooler for cooling the finished sinter discharged from the conveyor, whereby the thermal efficiency of the plant can be much improved.

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).

Abstract: A method and apparatus for the direct reduction of iron in a shaft furnace using gas from the gasification of solid fossil fuel, such as coal, in which the fuel gas is desulfurized and upgraded in the shaft furnace and direct reduction of iron oxide is carried out in the same furnace. Clean export fuel can be produced by this method along with direct reduced iron. The apparatus includes means for controlling the temperature of the process gas entering the furnace.

Abstract: A method for operating a blast furnace, characterized by: adding a prescribed volume of blast furnace gas to an air for blast fed to a hot stove; oxidizing, in the hot stove, CO contained in the blast furnace gas into CO.sub.2 and H.sub.2 contained therein into H.sub.2 O to prepare a blast containing CO.sub.2 and H.sub.2 O and additionally heated by the above-mentioned oxidation; blowing the resultant blast containing CO.sub.2 and H.sub.2 O into a blast furnace through tuyeres thereof; thereby controlling the calorific value at the portions around the tuyere exits as a result of the endothermic effect produced by the reactions at the portions around the tuyere exits of the CO.sub.2 and H.sub.2 O contained in the blast with red-hot coke in the blast furnace wherein the amount of the blast is substantially equal to that of a blast without addition of a blast furnace gas.

Abstract: Disclosed are a method and apparatus for manufacturing sponge iron by the continuous reduction of iron oxides in a shaft utilizing recirculation gases. Reaction gas is removed from the shaft furnace, substantially cleaned of all CO.sub.2 and H.sub.2 O, and then divided into at least two flow portions one of which is passed to a gas generator comprising a gas generating shaft substantially filled with a solid reducing agent and a plasma burner arranged in the lower portion of said shaft. An oxidant is injected into the hot gas from the plasma burner so as to form a gas mixture comprised primarily of CO and H.sub.2, which gas mixture is then mixed with the other flow portion of the cleaned reaction gas in such proportion that the temperature of the resulting reduction gas is suitable for the reduction of iron oxides in the shaft furnace.

Abstract: Disclosed are a method and apparatus for manufacturing sponge iron by the continuous reduction of iron oxides in a shaft utilizing recirculation gases. Reaction gas is removed from the shaft furnace, substantially cleaned of all CO.sub.2 and H.sub.2 O, and then divided into at least two flow portions one of which is passed to a gas generator comprising a plasma burner. A reducing agent such as pit coal is injected together with an oxidant into the hot gas from the plasma burner so as to form a gas mixture comprised primarily of CO and H.sub.2, which gas mixture is then mixed with the other flow portion of the cleaned reaction gas in such proportion that the temperature of the resulting reduction gas is suitable for the reduction of iron oxides in the shaft furnace.

Abstract: A method and apparatus for the dry collection of metallized fines from a direct reduction furnace cooling zone in which cooling gas removed from the cooling zone passes through a dust collector and the removed dust is cooled in a fluidized bed, the fluidizing gas being recirculated through an indirect cooler. The process is continuous and the fines are collected at a sufficiently low temperature for easy handling. The apparatus includes a hot gas cyclone in the cooling gas withdrawal line connected to a fluidized bed cooler, a conduit for withdrawing fluidizing gas from the fluidized bed cooler passes through a second cyclone dust collector then through an indirect cooler and returns to the fluidized bed cooler. Cool fines are withdrawn from the fluidized bed cooler into a collector.

Abstract: Apparatus for the direct reduction of iron oxide utilizing sulfur-containing gas such as coke oven gas for the process gas. Sulfur-containing gas is heated by indirect heat exchange and injected into the furnace above the reduction zone to transfer the sulfur to the hot burden. The apparatus includes an upper bustle zone for prereduction and sulfur transfer, a lower bustle zone for the final reduction of the burden to metallized iron, and means to recycle spent top gas through cooling zone as cooling gas.

Abstract: A process for the direct reduction of iron oxide by blowing into a reduction furnace a reducing gas which is prepared by reforming a mixture of a reduction furnace exhaust gas and a gas mainly composed of methane, which comprises the steps of dividing the gas mainly composed of methane into two branch streams, mixing the first branch stream gas with a part of the reduction furnace exhaust gas and supplying the resulting mixture to the externally heated reformer furnace, to produce a high-temperature reformed gas; mixing the second branch stream gas with said high-temperature reformed gas and during the course to the reduction furnace, subjecting the mixture to endothermic reforming reactions in an after-reactor without external heating, utilizing the sensible heat of the high-temperature mixed gas, controlling the self-reforming reactions so as to lower the temperature and simultaneously adjust the composition of the high-temperature mixed gas, and blowing the reducing gas obtained into the reduction furnace.

Abstract: A method and apparatus is disclosed for reducing metal ore to sponge metal in a vertical shaft, moving bed, gaseous reduction reactor by controlling the amount of gas intermixing between the reduction and cooling zones of the reactor to result in increased productivity and improved carburization of sponge iron. In accordance with a preferred embodiment, process efficiency is maximized while capital cost is minimized through the use of an optimally designed reactor with a pre-determined equivalent height to equivalent diameter ratio.

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).

Abstract: A method for the direct reduction of iron oxide utilizing sulfur-containing gas such as coke oven gas for the process gas. Sulfur-containing gas is heated and injected into a shaft furnace above the reduction zone into a prereduction and sulfur transfer zone for transferring sufficient sulfur from the process gas to the burden, that the catalyst for reforming the spent top gas will not be poisoned.

Abstract: A method and apparatus for the direct reduction of iron in a shaft furnace using gas from the gasification of solid fossil fuel, such as coal, in which the fuel gas is desulfurized and upgraded in the shaft furnace and direct reduction of iron oxide is carried out in the same furnace. Clean export fuel can be produced by this method along with direct reduced iron. The apparatus includes means for controlling the temperature of the process gas entering the furnace.

Abstract: A process and apparatus for making steel in a basic oxygen furnace by the top-blowing of pure oxygen and the bottom-blowing of a gas mainly composed of carbon dioxide are disclosed, in which a waste gas discharged from said basic oxygen furnace is utilized as the only source of the gas to be blown into a molten metal.

Abstract: An apparatus for the manufacture of steel by direct reduction of iron ore dust comprises a single reactor vessel and a tubular reduction dust extending into the vessel to a point closely adjacent to the bottom of the vessel. The reactor vessel is provided with a source of reducing gas containing a monoxide and a predominant amount of H.sub.2. Heating mechanisms for the reduction dust, the iron ore dust, the source of reducing gas and the vessel are provided. The apparatus also includes a mechanism for the recycling of heat and the components of the waste gases of the reactor vessel.

Abstract: Metallic scrap contaminated with combustibles is melted in a reverberatory melting furnace having two communicating wells; one being an enclosed sidewell, which is the receiving well for scrap material during melting, and the other being an enclosed main holding well for molten metal. The main well has burner means to provide heat for melting the metal and treating the scrap material. Heat from molten metal flowing between the main well and the sidewell produces exhaust gases by vaporizing the combustibles of the scrap material. An external passage circulates the exhaust gases from the sidewell to the main well for incineration by the main well's burner means. The external passage has an eductor means which draws the exhaust gases from the sidewell and propels them towards the main well.

Abstract: An improvement in a method for the batchwise gaseous reduction of iron ore to sponge iron in a multiple unit reactor system including a cooling reactor and a series of reduction reactors. Reduction is effected with a gas composed largely of carbon monoxide and hydrogen generated by reforming a mixture of steam and natural gas or other gaseous hydrocarbons at an elevated temperature. The reducing gas pressure drop through the system is decreased by using an out-of-line cooling reactor and cooling gas loop, thereby making it feasible to use three or more reduction reactors in series and thus enhance the efficiency of utilization of the reducing gas. Also the use of an out-of-line cooling reactor permits independent control of both the gas flow rate and gas composition in the cooling loop.

Abstract: A method and apparatus for reducing particulate iron oxide and producing molten iron in which coal and oxygen are impinged onto a molten iron bath in a closed vessel to melt the iron and gasify the coal. The hot off gas from the vessel is removed and used as the reductant in a counterflow shaft furnace to reduce iron oxide pellets and/or iron ore in a continuous manner. The hot reduced product from the shaft is discharged directly into the molten iron bath and melted.

Abstract: The invention relates to an apparatus and a declogging process for filtration installation for dust-laden gases presenting reducing properties, consisting in taking dust-free gas at the outlet of the filtration installation, oxidizing this gas and using the gaseous mixture resulting from this oxidization to declog the filtering element(s) of said installation.

Abstract: Pollutant-containing gases which are generated in a steel-making and/or coking plant are mixed with fresh air in at least one stream and passed through an incandescent bed of minerals, e.g. the sintering cake of an ore-sintering furnace. The resulting gases are then subjected to gas cleaning in at least one filtering or washing station.

Abstract: A method and apparatus for the direct reduction of iron oxide utilizing sulfur-containing gas such as coke oven gas for the process gas. Sulfur-containing gas is heated and injected above the reduction zone to transfer the sulfur to the hot burden. The apparatus includes an upper bustle zone for prereduction and sulfur transfer and a lower bustle zone for the final reduction of the burden to metallized iron.

Abstract: A preheating apparatus comprises a transfer duct connected to a dust collecting combustion chamber for steel making equipment, a hood fitting to the duct and shiftable to the position of one of preheating pits selectively, a bucket removably placed in each of the preheating pits and having an exhaust gas passage in its interior and openable bottom means at its bottom, and a communicating duct for holding each of the pits in communication with an outlet duct of the combustion chamber. The material to be charged into steel making equipment is placed into the bucket and preheated with exhaust gas from the combustion chamber. The apparatus assures savings in energy, improved safety and enhanced heat exchange efficiency.

Abstract: A method and apparatus for reducing particulate iron oxide to molten iron utilizing solid carbonaceous fuel as reductant in a shaft type reducing furnace, in which a furnace burden is formed of a mixture of iron oxide lumps or pellets and particulate solid fuel. Reacted top gas is upgraded and recirculated through the burden in counterflow relationship thereby heating and reducing the burden. The heat for reduction is generated by passing electric current through the burden. A portion of the heat for melting of reduced iron and a supplemental source of hot reducing gas is provided by oxy-fuel burners located in the shaft furnace above the molten iron pool.

Abstract: A cast house emissions recycle system for a blast furnace including a housing surrounding and enclosing the lower portion of the blast furnace and the tap holes and runners therefor and the hot metal ladle associated therewith, structure collecting the emissions from the housing, and a blower having an inlet duct communicating with the collecting structure and an outlet duct communicating with the cold air blast inlet to a hot blast stove for heating the air stream flowing therethrough and returning the heated air stream to the interior of the blast furnace; in an alternative construction, the output from the blower is connected to the combustion chamber of an associated hot blast stove as part of the fuel combustion air input thereto.

Abstract: A method and apparatus for producing molten iron in which pulverized coal is gasified with oxygen in an iron melting chamber, iron pellets on an upstanding hearth in the melting chamber are exposed to the gasification heat and melted. Molten iron trickles down from the hearth to a surrounding liquid bath. Off-gases from the chamber are utilized for direct reduction of iron oxide pellets to produce hot reduced iron pellets which are melted in the chamber.

Abstract: Apparatus for the direct reduction of iron and production of fuel gas in which a fossil fuel is gasified to produce a hot gas which is tempered with a carbon dioxide rich gas. The mixture is reacted with carbon to upgrade it in reducing potential and is desulfurized by reaction with lime in a first shaft furnace to form a hot reducing gas. The hot reducing gas is utilized as the reductant in a counterflow shaft reduction furnace, a minor portion of the spent reducing gas is recycled as tempering gas for the gas from the hot gasifier, and the major portion of spent reducing gas becomes a source of fuel gas. The apparatus includes a gasifier, counterflow shaft gas reactor, a shaft type direct reduction furnace and associated equipment.

Abstract: Iron, for example is directly recovered from relatively fine-grained (having a grain particle size range of less than 250 microns), iron-bearing ore whereby carbon-containing materials and oxygen-containing materials are fed through a molten metal bath and converted into a CO/H.sub.2 -rich reduction gas which is sequentially passed upwardly at gas speeds of at least 1.5 m/sec. through downwardly moving ore particles within a reduction apparatus comprised of a sequence of interconnected cyclones so that ore particles in each cyclone are in a state of suspension and in intimate contact with the reduction gas and each other whereby extensive reduction of the ore particles occurs at each cyclone so that after a last cyclone the so-reduced ore particles are directly fed into a smelting means, from which liquid iron is recovered.

Abstract: A method and apparatus are disclosed for achieving improved reduction efficiency and thermal economy in the reduction of particulate metal ores, e.g., iron ore, in a vertical shaft, moving bed reactor. The reactor consists of a primary reduction zone, a cooling zone and a secondary reduction zone located between the primary reduction zone and the cooling zone wherein ferric carbide formed in the primary reduction zone further reduces the residual iron oxide in the presence of an inert gas at a temperature below the melting point of the sponge iron. In one embodiment of the invention the gas produced by the reaction in the secondary reduction zone is withdrawn into a combustion chamber where it is mixed with air and burned, carbon dioxide is removed from the effluent gas of the combustion chamber and the remaining inert gas is recirculated to the secondary reduction zone.

Abstract: In the dry quenching apparatus for red hot coke, the amount of quenching gas to a cooling chamber is controlled by controlling the speed of rotation of a blower in order to fix a diverging point between the positive pressure and the negative pressure at one point. The pressure around the diverging point is controlled so that the pressure is maintained at 0.+-.5 mm in Aq.

Abstract: A method and apparatus for the direct reduction of iron ore are disclosed. A mixture of iron ore, solid carbonaceous fuel and, if sulfur is present, calcined limestone or dolomite, are used. The carbonaceous material can be cellulosic material (wood waste, paper, particularly municipal trash, garbage, etc.), charcoal, or coal (preferably sub-bituminous coal or lignite). The above feed is continuously charged into a gasification and initial reduction zone of a shaft furnace which is partitioned partially from the remainder of the furnace. Oxygen and hot steam are introduced into the upper portion of the said zone. Partial combustion or pyrolysis of the fuel and reaction with steam take place, producing reducing gas which initiates reduction of the iron ore. Ore and gas flow downwardly through conduits into the final reduction zone. Meanwhile, hydrogen-enriched reducing gas is introduced in the middle of the final reduction zone.

Abstract: A method and a device for drying machine parts, e.g. balls or rolls for roller bearings, upon washing the parts in a washing liquid containing a solvent, especially a polluting solvent. Upon washing, the wet parts are fed into a chamber, and a dry, hot gas is injected into the chamber and evacuated therefrom. The evacuated humid gas is recirculated in a circuit and, upon being compressed and cooled, the gas is freed from its solvent contents in a liquid separator and is heated before re-injection into the chamber. A reduced gas pressure is maintained in the chamber by controlling the gas flow in the recirculation circuit, and the gas in the chamber is cooled, so that the partial pressure of the solvent in the chamber is substantially reduced.

Abstract: A method and apparatus for the direct reduction of iron in which a fossil fuel is gasified to produce a hot gas which is tempered with a carbon dioxide lean gas. The mixture is reacted with carbon to upgrade it in reducing potential and is desulfurized by reaction with lime in a first shaft furnace to form a hot reducing gas. The hot reducing gas is utilized as the reductant in a counterflow shaft reduction furnace and the spent reducing gas is recycled as tempering gas for the gas from the hot gasifier. The apparatus includes a gasifier, counterflow shaft gas reactor, a shaft type direct reduction furnace and associated equipment.

Abstract: A method and apparatus for heat treating metals to remove contaminants. Contaminated scrap metal is fed into one end of a rotating inclined retort. Heat is applied to the retort as the scrap metal is conveyed therein to remove the contaminant, and the processed metal is discharged from the opposite end of the retort. Combustible waste gases generated through the processing are fed to an afterburner where the combustible gases are burned and are discharged from the afterburner into a stack. A portion of the hot combusted gases are returned from the stack to the discharge end of the retort to thereby minimize oxidation of the scrap metal being treated as well as conserving fuel.

Abstract: Apparatus for reducing particulate iron oxide to molten iron utilizing solid carbonaceous fuel as reductant in a shaft type reducing furnace, in which a furnace burden is formed of a mixture of iron oxide lumps or pellets and particulate solid fuel. Reacted top gas is upgraded and recirculated through the burden in counter-flow relationship thereby heating, reducing and melting the burden. The heat for reduction and melting is generated by passing electric current through the burden.

Abstract: In a dry type method and apparatus for quenching coke wherein hot coke charged in a coke quenching installation is cooled by circulating cooling gas in the installation through a closed circulating system including a blower and a heat exchanger, the composition of the cooling gas is analyzed and compared with a reference gas composition and air or nitrogen gas is supplemented to the closed circulating system in accordance with the result of comparison. A portion of the circulating gas is discharged to the atmosphere when air or nitrogen gas is supplemented. Air is supplemented on the high temperature discharge side of the circulating cooling gas while nitrogen gas is supplemented on the low temperature inlet side. The cooling gas is discharged to the atmosphere before the supplementation of the nitrogen gas.

Abstract: A pilot flame to be positioned close to the charge opening of a cupola which uses carbon monoxide as a fuel in the presence of a fresh supply of combustion air, such carbon monoxide being drawn off from a position on the cupola where the temperature is above the self-ignition temperature of the carbon monoxide. Air preheated to a temperature above the self-ignition temperature of carbon monoxide may also be supplied.

Abstract: A method and apparatus for reducing particulate iron oxide to metallic iron utilizing solid carbonaceous fuel as reductant in a shaft type reducing furnace, in which a furnace burden is formed of a mixture of iron oxide lumps or pellets and particulate solid fuel. Reacted top gas is upgraded and recirculated through the burden in counter-flow relationship thereby heating and partially reducing the burden. The heat for final reduction is generated by passing electric current through the burden.