Abstract: A rotary hearth furnace includes: a furnace body which surrounds a ring-like space; a hearth portion which forms a bottom portion of the ring-like space and is rotatable in the rotational direction; a gas exhaust portion which discharges an exhaust gas generated in the ring-like space to the outside of the furnace body; an introducing portion; and a flow rate regulating portion. The introducing portion is disposed upstream of the gas exhaust portion in the rotational direction and introduces a pressure regulating gas into a non-heating section of the ring-like space. The flow rate regulating portion is disposed between the introducing portion and the gas exhaust portion and regulates a flow rate of a gas by adjusting an opening area of the non-heating section.

Abstract: A finish heat treatment apparatus for an iron powder. Raw iron powder is placed on a continuous moving hearth and continuously charged into the apparatus. In a pretreatment zone, the raw iron powder is subjected to a pretreatment of heating the raw iron powder in an atmosphere of hydrogen gas and/or inert gas at 450 to 1100° C. In decarburization, deoxidation, and denitrification zones, the pretreated iron powder is subsequently subjected to at least two treatments of decarburization, deoxidation, and denitrification. In the pretreatment zone, a hydrogen gas and/or an inert gas serving as a pretreatment ambient gas is introduced separately from an ambient gas used in the at least two treatments is introduced from the upstream side of the pretreatment zone and released from the downstream side so as to flow in the same direction as a moving direction of the moving hearth.

Abstract: An annular workplace quenching method includes: cooling an annular workpiece with an inner die arranged radially inward of the workpiece heated at a quenching temperature; pressing the workpiece in a width direction at a low pressure and inserting the workpiece in an outer die with restraint of an inner peripheral surface of the workpiece continued, when the restraint is started by contact with the inner die, after a temperature of the workpiece is decreased to 500° C. or lower but before the temperature is decreased to a martensitic transformation start temperature (Ms point); and restraining the workpiece in the width direction by pressing the workpiece in the width direction at a high pressure, and restraining an outer peripheral surface of the workpiece that undergoes volume expansion due to martensitic transformation, using the outer die, after the temperature of the workpiece is decreased to the Ms point or lower.

Abstract: A process and a device for charging a primary product for pig iron into a smelting unit are provided. According to the process and device, some of the primary product that has been formed by reducing oxidic iron carriers is stored in the hot state in a reservoir tank before being supplied into the storage device or charging device that is directly connected to the smelting unit.

Abstract: Disclosed herein are reactors and methods for forming alloys based on titanium-aluminium or alloys based on titanium-aluminium inter-metallic compounds. The reactor comprises a first section having an inlet through which precursor material comprising titanium subchlorides and aluminium can be introduced. The first section is heatable to a first temperature at which reactions between the titanium subchlorides and aluminium can occur, and further comprises a gas outlet via which any gaseous by-product formed can be removed. The reactor also comprises a second section which can be heated to a second temperature at which reactions of material transferred from the first section can occur to form the titanium-aluminium based alloy, a gas driver adapted in use to cause any gaseous by-product formed in the reactions in the second section to move in a direction towards the first section, and an intermediate section between the first and second sections.

Abstract: A system of coal gasification and direct ironmaking attains both heat recovery in a coal-based direct ironmaking process and a reduction in equipment investment in a coal gasification process. A waste heat boiler in the system recovers heat of gas exhausted from a coal gasification furnace. A heater in exhaust gas lines of a heat reduction furnace in the coal-based direct ironmaking process superheats the steam generated by and exhausted from the waste heat boiler. A superheated steam line supplies the steam superheated by the heater as an oxidant to the coal gasification furnace.

Abstract: An apparatus for manufacturing molten iron includes a reduction furnace having a charging device that is capable of preventing segregation. The reduction furnace for reducing an iron-containing material used for manufacturing molten iron may include a charging hole where the iron-containing material is charged, a first guide plate sloped toward a first direction in the reduction furnace to guide the iron-containing material to the inside of the reduction furnace, and a second guide plate fixed and sloped toward a second direction intersecting the first direction in the reduction furnace to guide the iron-containing material dropped and guided by the first guide plate. A dropping direction of the iron-containing material dropped and guided by the first guide plate is changed when the iron-containing material is guided by the second guide plate.

Abstract: A system of coal gasification and direct ironmaking attains both heat recovery in a coal-based direct ironmaking process and a reduction in equipment investment in a coal gasification process. A waste heat boiler in the system recovers heat of gas exhausted from a coal gasification furnace. A heater in exhaust gas lines of a heat reduction furnace in the coal-based direct ironmaking process superheats the steam generated by and exhausted from the waste heat boiler. A superheated steam line supplies the steam superheated by the heater as an oxidant to the coal gasification furnace.

Abstract: A plant for the production of ore comprising a proportion of fines, additives and green agglomerates optionally containing a binder, provided with an outer coating consisting of a combustible containing fine-grained carbon, such as coke. In the plant, the ore is mixed with the additives and the optionally available binder. The mixture is pelletized and the green agglomerates thus formed are coated with the combustible, whereby the combustible is introduced into an agglomeration drum. In order to enable continual production of homogeneous-quality green agglomerates, the mixture is pelletized in the agglomeration drum and the combustible is added in an area of the longitudinal extension of the agglomeration drum where the size of the green agglomerates formed in the agglomeration drum is sufficient for further processing.

Abstract: Method of constructing and installing a direct smelting unit comprising a smelting vessel (11). The vessel is prefabricated off site in three modules (11A, 11B, 11C) which are then transported to the installation site where they are hoisted by a crane and deposited sequentially on top of one another and joined together by welding to form a unitary vessel. The vessel modules are prefabricated so as to be internally lined with water cooling panels connected to water inlet and outlet connectors (62) on the exterior of the circumferential wall sections of those modules. A vessel access tower is formed in modules brought together to envelop the tower and carrying water supply and return piping which is connected to the water inlet and outlet connectors (62) of the cooling panels.

Abstract: A system for cooling and recuperative heating of a slurry in a metallurgical process which includes heat exchangers, pumps and autoclaves is described herein. The heat exchangers use a non-scaling common liquid heat transfer medium. Preferably, the heat exchangers are tube-in-tube heat exchangers with 3 to 7 slurry tubes in each heat exchanger. An advantage of this system is that it does not use flash tanks. To minimize abrasive wear on impinged surfaces, the velocity of the slurry is not more than 5 meters per second. The slurry comprises a solids concentration of 25% to 50%. Preferably, the pumps in the system are float-type pumps in which the driven liquid from the discharge pumps is also used as the drive liquid for the feed pumps.

Abstract: The present invention provides a method of manufacturing direct reduction iron and a reduction firing apparatus. The apparatus may be a dual-chamber stepping reduction furnace, a single chamber stepping reduction furnace or a single hearth down-draft reduction furnace, wherein the dual-chamber stepping reduction furnace includes a left chamber, a right chamber, a material containing device, a step mechanism, a slag distributing device, a charging device, heating burners, a fume extraction path, a charging device, a material receiving tank having a sealing cap and a slag discharging path.

Abstract: A rotary furnace hearth wherein a hearth carriage carrying a hearth comprises a plurality of hearth carriages respectively having propulsion systems, wherein adjoining hearth carriages are coupled by coupling bolts and nuts via spacers interspaced in a single row in a horizontal plane, whereby even if the hearth carriages deform due to heat at the time of operation, they are structured to be able to freely deform without mutual constraint in the event of curved deformation, so the hearth carriages are maintained in individually stable states at all times.

Abstract: A screw conveyor for conveying an object to be conveyed, supported by a casing 1 by rotation of a screw 2, in which wear of a screw blade and decrease in conveyance efficiency are prevented without the need for extra power. Load on an electric motor 3 or the like for rotating the screw 2 or a value corresponding to the load is measured, and if the value is equal to or larger than a preset upper limit value, a screw shaft 2a is lifted up to increase a gap between an edge of the screw blade 2b and a bottom portion of the casing 1.

Abstract: Techniques for suppressing NOx in an indurating furnace include the use of a premix burner, the use of a staged fuel injector structure to enhance fuel lean conditions in the downdraft, and the use of a Venturi mixture structure in the downcomer.

Abstract: An apparatus for the removal of uranium from a body of material is provided. The apparatus has at least one ultrasonic extractor, having a bottom and a top. The at least one ultrasonic extractor is configured to accept solids at the bottom and acid at the top, and has a mixing screw and at least one source of ultrasonic energy. The mixing screw is configured to transport the solids in a direction countercurrent to the acid in the at least one ultrasonic extractor; and the source of ultrasonic energy is configured to impart ultrasonic energy into the solids and the acid, as the solids and the acid traverse the at least one ultrasonic extractor countercurrently.

Abstract: Systems and methods for use in processing raw material (e.g., iron bearing material) include a linear furnace apparatus extending along a longitudinal axis between a charging end and a discharging end (e.g., the linear furnace apparatus includes at least a furnace zone positioned along the longitudinal axis). Raw material is provided into one or more separate or separable containers (e.g., trays) at the charging end of the linear furnace apparatus. The separate or separable containers are moved through at least the furnace zone and to the discharging end where the processed material is discharged resulting in one or more empty containers. One or more of the empty containers are returned to the charging end of the linear furnace apparatus to receive further raw material.

Abstract: A reduced iron discharging screw conveyer is provided in a rotary hearth furnace and discharges reduced iron out of the rotary hearth furnace. The rotary hearth furnace produces the reduced iron by charging and heating a pellet including metallic oxide and coal material onto a rotary hearth rotating in a horizontal plane. The reduced iron discharging screw conveyer has a rotary shaft and a screw blade which is spirally formed on an outer surface of the rotary shaft. A lead angle ? of the screw blade 5a satisfies a condition of “0.46 rad ???0.79 rad”. A ratio (h/D) between height h of the screw blade and an outer diameter D of the screw conveyer is smaller than 0.2, and a ratio (t/h) between thickness t and height h of the screw blade is larger than or equal to 0.12.

Abstract: A vol-oxidizer of spent nuclear fuel, the spent nuclear fuel is injected to a reaction portion, the reaction portion is connected to a driving portion and oxidizes the spent nuclear fuel by rotating and back-rotating the spent nuclear fuel. The oxidized powder of the spent nuclear fuel is gathered in a discharge portion located in a lower portion of the reaction portion. By providing minute powder particles for recycling and a post process of the spent nuclear fuel, even though a size of an apparatus is small, processing a large amount is possible. Time required for oxidation can be reduced, and the powder is readily discharged by gravity since the apparatus is vertically configured.

Abstract: To facilitate a trouble-free charging of scrap metal having differing constitutions, such as light and heavy scrap metal, from a lower discharge opening of a shaft-shaped charging device or a charging stock preheater (1) into a melting vessel by a pusher (13), the lateral surfaces of the pusher (13) are formed so as to converge from the upper side to the lower side and the actuating device (2) of the pusher (13) is pivotably supported in a frame structure (3) about a horizontal axis. In addition, the upper boundary of the discharge opening for the charging stock from the shaft (2) is preferably formed by a horizontal, rotatably supported roller (26), more preferably with engaging elements (30) distributed around the circumferential surface. Sections of the charging device that are severely mechanically stressed are preferably formed by steel billet sections connected to form a structural unit.

Abstract: A method for discharging a reduced product produced on a movable hearth of a movable-hearth furnace uses a discharging device. The discharging device includes a removal unit for removing the reduced product from the movable hearth, a separation unit for separating the reduced product from a solid reductant, a leaving-returning unit for either leaving substances other than the reduced product on a solid reductant layer or returning the substances onto the solid reductant layer, and a discharge unit for discharging the reduced product to the outside of the movable-hearth furnace.

Abstract: Systems and methods for use in processing raw material (e.g., iron bearing material) include a linear furnace apparatus extending along a longitudinal axis between a charging end and a discharging end (e.g., the linear furnace apparatus includes at least a furnace zone positioned along the longitudinal axis). Raw material is provided into one or more separate or separable containers (e.g., trays) at the charging end of the linear furnace apparatus. The separate or separable containers are moved through at least the furnace zone and to the discharging end where the processed material is discharged resulting in one or more empty containers. One or more of the empty containers are returned to the charging end of the linear furnace apparatus to receive further raw material.

Abstract: The present invention provides a reducing furnace of the rotary hearth-type and a method for reducing a metal oxide simplified in the process from dehydration to molding, according to which a moisture-rich powdery raw material is reduced at low cost. The present invention also provides an operation method whereby dusts or sludge generated in the refining or processing of metal are economically recycled. A powdery mixture having a moisture content of 100% or higher relative to the total mass of a metal oxide-containing powder and a carbon-containing powder is made into a slurry and mixed by stirring. Thereafter, the slurry is dehydrated to a moisture content of 16 to 26% and compression-molded into articles. The cylindrical or granular shaped articles having a thickness or diameter of 30 mm or less thus obtained are fed to a zone the atmospheric temperature of which is 1170° C. or lower in the furnace and reduced through calcination by a rotary hearth reducing furnace thereby to provide a metal.

Abstract: A method for discharging a reduced product produced on a movable hearth of a movable-hearth furnace uses a discharging device. The discharging device includes a removal unit for removing the reduced product from the movable hearth, a separation unit for separating the reduced product from a solid reductant, a leaving-returning unit for either leaving substances other than the reduced product on a solid reductant layer or returning the substances onto the solid reductant layer, and a discharge unit for discharging the reduced product to the outside of the movable-hearth furnace.

Abstract: The present invention relates to a method and equipment, whereby matte with a high non-ferrous metal content and disposable slag are produced simultaneously in a suspension-smelting furnace from non-ferrous sulphide concentrate. According to the invention, a carbonaceous reducing agent is charged to the lower furnace of a suspension smelting furnace via tuyeres to the part of the furnace which has a reduced cross-sectional area.

Abstract: In a method and an apparatus for cooling a reduced-iron agglomerate in a reduced-iron agglomerate production equipment wherein an iron oxide agglomerate is reduced in a reducing furnace and discharged as a reduced-iron agglomerate, a conveyer to convey said reduced-iron agglomerate is installed at the outlet of said reduced-iron agglomerate production equipment, a plurality of spray nozzles are installed above, or above and below, said conveyer at intervals in the conveying direction of said reduced-iron agglomerate, and said reduced-iron agglomerate on said conveyer is cooled intermittently by ejecting cooling water, continuously or intermittently, through said spray nozzles.

Abstract: A rotary hearth furnace is provided to simplify detachment and assembly operations of a reduced iron discharging screw. At both side walls of an insulating housing 2a constituting in part of a furnace body 2 of a rotary hearth furnace 1 are installed through-holes which a spiral blade 42 of a reduced iron discharging screw 4 can pass through, each of the through-holes is closed by an inner hatch member 8 and an outer hatch member 9 which are externally mounted in a removable fashion to a rotary shaft 41 of the reduced iron discharging screw 4, an inner screw supporting device 10 is installed in the outside at an inner periphery side of the hearth 3 as well as an outer screw supporting device 20 is installed in the outside at an outer periphery side of the hearth 3. The reduced iron discharging screw 4 is detached from the furnace body 2 via the through-holes and assembled to the furnace body 2 via the through-holes by using the inner screw supporting device 10 and the outer screw supporting device 20.

Abstract: An annular rail 6 is fixed on the lower surface of a moving hearth 2, and the rail 6 is supported from below by support rollers 7 provided with elevating devices 8. The moving hearth 2 is continuously or intermittently moved downward by the elevating devices 8 depending on the thickness of a metal oxide layer formed by the deposition of powder of metal oxide agglomerates mixed into the furnace together with the metal oxide agglomerates so that a gap is provided between the surface of the metal oxide layer and the edge of the blade of a discharge screw 4 during operation.

Abstract: The present invention provides a sealing mechanism of a feeding device for feeding lumps and/or powder to a moving-hearth heating furnace. The feeding device includes a vibrating feeder having a trough in which a hole for feeding the lumps and/or powder to the furnace is formed and a duct for guiding the lumps and/or powder dropped through the hole to a hearth of the heating furnace. The sealing mechanism includes a water sealing mechanism having a skirt plate, a weir plate, a side surface of the duct, and liquid. The skirt plate is provided on the lower surface of the trough. The weir plate is provided above a ceiling of the heating furnace. The liquid is kept in a tank serving as a pool of liquid which is formed by the side surface of the duct and the weir plate.

Abstract: Novel forms of molybdenum metal, and apparatus and methods for production thereof. Novel forms of molybdenum metal are preferably characterized by a surface area of substantially about 2.1 m2/g to substantially about 4.1 m2/g. Novel forms of molybdenum metal are also preferably characterized by a relatively uniform size.

Abstract: An apparatus and method for the direct reduction of iron oxide utilizes a hearth furnace having a vitreous hearth layer of conditioning materials, with the vitreous hearth layer introduced onto a refractory surface of the furnace. The vitreous hearth layer may have upper layers of coating compounds including carbonaceous materials, onto which iron oxide feed material is placed with the carbonaceous materials assisting with segregating the reduced molten iron nuggets from the vitreous hearth layer. The conditioning materials may include compounds such as silicon oxide, magnesium oxide, iron oxides, and aluminum oxide. The conditioning materials are placed in solid or liquid form on the refractory surface, which allows the conditioning materials to raise the melting temperature of the vitreous hearth layer onto which the coating compounds and iron oxide materials are placed.

Abstract: The present invention provides a method of operation and a facility for the same suppressing the generation of dioxins in the combustion exhaust gas and efficiently reclaiming heat from high temperature combustion exhaust gas when firing and reducing fines of chromium ore, iron ore, or other ore or pellets formed from dust sludge, etc. containing iron oxide or other metal oxides generated in the metal industry in a reducing rotary hearth furnace. This treats the combustion gas generated in the reducing rotary hearth furnace to make the temperature of the gas 800° C. or higher for at least a certain time, to make the concentration of the carbon monoxide not more than 200 ppm in terms of volume ratio and to achieve a sufficiently well developed turbulent state at least at one of the inside of the exhaust gas outlet duct and the vicinity of the exhaust gas outlet duct for at least a certain time, then rapidly cooling the gas.

Abstract: The invention is a method and apparatus for producing beneficiated titanium oxides using a modified rotary hearth furnace, that is a finisher-hearth-melter (FHM) furnace. In the method the refractory surface of the hearth is coated with carbonaceous hearth conditioners and refractory compounds, where onto said hearth is charged with pre-reduced agglomerates. The pre-reduced agglomerates is leveled, then heated until molten, and then reacted with the carbon and reducing gas burner gases until any residual iron oxide is converted to iron having a low sulfur content. Fluid slag and molted iron forms melted agglomerates. The fluid slag is rich in titanium. The melted agglomerates are cooled, and then the melted agglomerates and the hearth conditioners, including the refractory compounds, are discharged onto a screen, which separate the melted agglomerates from the hearth conditioner.

Abstract: In a rotary hearth furnace for producing reduced metal through heating and reducing carbon containing materials composed of at least metal oxide-containing material and carbon-containing reduction material, a hearth structure is provided by which a refractory in a hearth lateral end is not damaged and carbon containing materials do not fall down to a water sealing section of the rotary hearth furnace. The upper part of a hearth lateral end 1a is covered with the lower end 2a of a side wall 2 of a hood covering the whole hearth, and a cooling means 3 is installed in the side wall lower end 2a.

Abstract: A process for separating and recovering a desired metal as metal oxide from raw material is provided. The process includes placing the raw material and a reductant in a container to form a reducing microclimate within the container. A housing having an oxidizing atmosphere is heated to maintain a temperature zone within the housing at a heating temperature sufficient to expose the raw material in the container to a reaction temperature. The container containing the raw material is conveyed through the temperature zone in the housing to expose the raw material and the reductant to the reaction temperature wherein the metal oxide is reduced to a gaseous metal that exits the container. Once outside the container, the gaseous metal is exposed to the oxidizing atmosphere of the temperature zone wherein the desired metal is oxidized to metal oxide and the metal oxide is collected. In preferred embodiments, the raw material is EAF dust and the desired metal is zinc.

Abstract: Heat-treated products discharged from a discharge port of a movable hearth type heat treatment furnace, for example a rotary hearth type reduction furnace are discharged to a sorting means, the heat-treated products that foreign substances have been removed, are discharged through a seal leg into which anti-reoxidation gas is blown from a gas blowing nozzle, to a receiving recess of a receiving pan provided within a case having a hopper attached thereto which is a feeding means, and then a scraper is swung to discharge the heat-treated products deposited on the top surface of the receiving recess from the longitudinal ends of the receiving pan and simultaneously to quantitatively feed it to a molten iron-manufacturing furnace 8, which is a downstream side facility, from the bottom side discharge port of the casing having a hopper attached thereto, and in addition, dust removal/cooling means for produced gas of the molten iron-manufacturing furnace and means for regulating the amount of produced gas are provid

Abstract: A rotary hearth furnace is provided to simplify detachment and assembly operations of a reduced iron discharging screw. At both side walls of an insulating housing 2]a constituting in part of a furnace body 2 of a rotary hearth furnace 1 are installed through-holes which a spiral blade 42 of a reduced iron discharging screw 4 can pass through, each of the through-holes is closed by an inner hatch member 8 and an outer hatch member 9 which are externally mounted in a removable fashion to a rotary shaft 41 of the reduced iron discharging screw 4, an inner screw supporting device 10 is installed in the outside at an inner periphery side of the hearth 3 as well as an outer screw supporting device 20 is installed in the outside at an outer periphery side of the hearth 3. The reduced iron discharging screw 4 is detached from the furnace body 2 via the through-holes and assembled to the furnace body 2 via the through-holes by using the inner screw supporting device 10 and the outer screw supporting device 20.

Abstract: The invention concerns a method for producing melt iron comprising the following steps: a) reducing the iron ore particles to form pre-reduced iron comprising excess free carbon; b) hot process transfer of the pre-reduced iron in a smelting furnace; c) smelting the pre-reduced iron in a smelting furnace to obtain melt iron.

Abstract: A method of making metallic iron in which a compact, containing iron oxide such as iron ore or the like and a carbonaceous reductant such as coal or the like, is used as material, and the iron oxide is reduced through the application of heat, thereby making metallic iron. In the course of this reduction, a shell composed of metallic iron is generated and grown on the surface of the compact, and slag aggregates inside the shell. This reduction continues until substantially no iron oxide is present within the metallic iron shell. Subsequently, heating is further performed to melt the metallic iron and slag. Molten metallic iron and molten slag are separated one from the other, thereby obtaining metallic iron with a relatively high metallization ratio.

Abstract: To provide an operating method of a rotary hearth furnace for producing reduced iron in which a stuck substance stuck on the hearth surface is removed from the hearth surface to thereby prevent or reduce the wear of the knife edge of a screw of a discharge device, enabling continuous operation for a long period and capable of achieving high availability factor. The hearth surface is quenched by spraying or the like to generate cracks in the stuck substance on the hearth, and the stuck substance is scraped to thereby remove it from the hearth.

Abstract: A furnace discharge system for removing material from a hearth (18) of a rotary hearth furnace (10) and method of operation. The system includes at least two material discharge augers (28, 30) positioned above the hearth (18) of the rotary hearth furnace (10). Each discharge auger (28, 30) is operatively mounted to allow for height adjustment of the discharge auger (28, 30) in alternating sequence from a material removal position to an elevated material by-pass position.

Abstract: A process for thermal treatment of residual materials containing heavy metal and iron oxide, including providing a multiple-hearth furnace having hearths provided one above the other, depositing the residual materials continuously on a top hearth of the hearths, gradually transferring the residual materials to lower hearths of the hearths, introducing reducing agents to at least one of the hearths and reacting the residual materials to form heavy metals and directly reduced iron, exhausting gases containing heavy metals from below hearths of the hearths where the heavy metals are being vaporised, re-injecting at least a part of the gases into the multiple-hearth furnace from above the hearths of the hearths where the heavy metals are being vaporised, and discharging the directly reduced iron together with residues of the reducing agents in an area of a bottom hearth of the hearths in the multiple hearth furnace.

Abstract: A method for improving the direct reduction of metal oxides in a continuous furnace with a rotating hearth. The method deposits two or several layers with increasing metal oxide contents in each layer towards a top loading surface and decreases carbon contents towards the top loading surface, which carbon will be preheated to a temperature of the order of 200° C. while the metal oxides will be preheated to a temperature of 800° C. The furnace is provided with equipment producing at the loading surface triangular grooves and in first and second zones of the furnace matching equipment with double action.

Abstract: An apparatus for producing reduced iron by agglomerating a mixed powder of an iron material and a reducing agent to form compacts like briquettes or pellets, and reducing the compacts in a high temperature atmosphere is disclosed. In the apparatus, a rotary hearth in an annular form is rotatably supported. Right and left furnace walls and a ceiling are provided to cover an area above the rotary hearth, thereby forming a space portion in a high temperature atmosphere. A compact supply portion, and a compact discharge portion are provided adjacently in the ceiling. Partitioning members are provided as partitions between the compact supply portion, the compact discharge portion, and the high temperature atmosphere space portion.

Abstract: The present invention is an apparatus and method for the direct reduction of iron oxide utilizing a rotary hearth furnace to form a high purity carbon-containing iron metal button. The hearth layer may be a refractory or a vitreous hearth layer of iron oxide, carbon, and silica compounds. Additionally, coating materials may be introduced onto the refractory or vitreous hearth layer before iron oxide ore and carbon materials are added, with the coating materials preventing attack of the molten iron on the hearth layer. The coating materials may include compounds of carbon, iron oxide, silicon oxide, magnesium oxide, and/or aluminum oxide. The coating materials may be placed as a solid or a slurry on the hearth layer and heated, which provides a protective layer onto which the iron oxide ores and carbon materials are placed. The iron oxide is reduced and forms molten globules of high purity iron and residual carbon, which remain separate from the hearth layer.

Abstract: An apparatus for producing a reduced metal includes a moving hearth reducing furnace, a feeding section, a metal discharge section, a gas discharge section, and a regenerative burner. The moving hearth reducing furnace heats a raw material composed of a metal oxide component and a carbonaceous reducing component to form the reduced metal. The feeding section feeds the raw material into the moving hearth reducing furnace. The metal discharge section discharges the reduced metal from the moving hearth reducing furnace. The gas discharge section discharges waste gas from the furnace and is disposed in a reducing process between the moving hearth reducing furnace and the metal discharge section. The regenerative burner functions as a heat source for the moving hearth reducing furnace.

Abstract: Process and apparatus for regenerating spent acid liquor includes a primary roasting furnace for evaporating a substantial portion of the liquid from the spent acid to produce acid vapors and partially roasted metal salts. The partially roasted metal salts are transferred to a secondary roasting chamber where the acids adhering to the surface of the metal salts is vaporized and the metal salts are oxidized. The acid vapors from the primary roasting furnace are then transferred to an absorption column to regenerate the acid. The primary roasting furnace is operated at a different temperature from the secondary roasting chamber and has different retention times for the metal salts. The secondary roasting chamber includes a raking device to mix and convey the metal salts during the secondary roasting step to produce a uniformly roasted metal oxide.

Abstract: The present invention is an apparatus and method for the direct reduction of iron oxide utilizing a rotary hearth furnace to form a high purity carbon-containing iron metal button. The hearth layer may be a refractory or a vitreous hearth layer of iron oxide, carbon, and silica compounds. Additionally, coating materials may be introduced onto the refractory or vitreous hearth layer before iron oxide ore and carbon materials are added, with the coating materials preventing attack of the molten iron on the hearth layer. The coating materials may include compounds of carbon, iron oxide, silicon oxide, magnesium oxide, and/or aluminum oxide. The coating materials may be placed as a solid or a slurry on the hearth layer and heated, which provides a protective layer onto which the iron oxide ores and carbon materials are placed. The iron oxide is reduced and forms molten globules of high purity iron and residual carbon, which remain separate from the hearth layer.

Abstract: A method for manufacturing reduced iron agglomerates comprises the steps of supplying iron oxide agglomerates including carbonaceous material on a moving hearth, heating and reducing the agglomerates to yield reduced iron agglomerates while the moving hearth moves in the reduction furnace, discharging the reduced iron agglomerates from the reduction furnace, recovering the reduced iron agglomerates, and removing seized hearth fragments separated from the moving hearth in close proximity to a discharge location or a recovery location for the reduced iron while the reduction furnace is being operated. According to the method, the reduction furnace can be operated for a long period of time without stopping the operation thereof and supply of the iron oxide agglomerates.

Abstract: A continuous nickel matte converter and method for the efficient production of low iron nickel-rich mattes from high-iron nickel-rich mattes, with minimal environmental impact. The present invention processes high-iron, nickel-rich primary furnace mattes to produce low iron, nickel-rich mattes, low value metal-containing slag and sulfur dioxide rich-off gas, with improved cobalt recovery. It eliminates use of the Peirce-Smith converter, with its undesirable environmental, metallurgical and economic features.