Abstract: A method and system for making metallic iron nodules with reduced CO2 emissions is disclosed. The method includes: assembling a linear hearth furnace having entry and exit portions, at least a conversion zone and a fusion zone, and a moving hearth adapted to move reducible iron bearing material through the furnace on contiguous hearth sections; assembling a shrouded return substantially free of air ingress extending adjacent at least the conversion and fusion zones of the furnace through which hearth sections can move from adjacent the exit portion to adjacent the entry portion of the furnace; transferring the hearth sections from the furnace to the shrouded return adjacent the exit portion; reducing reducible material in the linear hearth furnace to metallic iron nodules; and transporting gases from at least the fusion zone to the shrouded return to heat the hearth sections while in the shrouded return.

Abstract: A hearth furnace for producing metallic iron material has a furnace housing having a drying/preheat zone, a conversion zone, a fusion zone, and optionally a cooling zone, the conversion zone is between the drying/preheat zone and the fusion zone. A moving hearth is positioned within the furnace housing. A hood or separation barrier within at least a portion of the conversion zone, fusion zone or both separates the fusion zone into an upper region and a lower region with the lower region adjacent the hearth and the upper region adjacent the lower region and spaced from the hearth. An injector introduces a gaseous reductant into the lower region adjacent the hearth. A combustion region may be formed above the hood or separation barrier.

Abstract: An oven according to some embodiments includes an oven chamber in which food is cooked, a heating element, a fan, a sensor for sensing the temperature of the oven chamber, a remote input device, and a controller configured to receive a signal from the remote input device and to change the fan or heating element based at least in part upon the signal received from the remote input device. In a method of operating the oven according to some embodiments, the oven enters an operating mode from an energy-savings mode responsive to receiving an signal from a remote device.

Abstract: Provided is a rotary hearth furnace which can stir exhaust gas within a furnace, to efficiently burn flammable gas within the exhaust gas and to efficiently heat an object to be heated, and which can contribute to reduction of specific energy consumption and improvement of productivity. A rotary hearth furnace (1) has therein a series of zone spaces (3) which are divided by vertical walls (2) hanging from a ceiling (1c). Among the zone spaces (3), the zone space to which an exhaust gas duct (4) is attached is constructed as an exhaust zone (3a). An oxygen-containing gas supply unit (5) is provided in the vicinity of the lower edge of the vertical wall (2) which divides the exhaust zone (3a) from the other zone spaces (3). Further, the exhaust gas duct (4) is disposed on the outer periphery side or the inner periphery side from the center of the width of the zone space (3).

Abstract: Method and system for producing metallic nuggets includes providing reducible mixture (e.g., reducible micro-agglomerates; reducing material and reducible iron bearing material; reducible mixture including additives such as a fluxing agent; compacts, etc.) on at least a portion of a hearth material layer. In one embodiment, a plurality of channel openings extend at least partially through a layer of the reducible mixture to define a plurality of nugget forming reducible material regions. Such channel openings may be at least partially filled with nugget separation fill material (e.g., carbonaceous material). Thermally treating the layer of reducible mixture results in formation of one or more metallic iron nuggets. In other embodiments, various compositions of the reducible mixture and the formation of the reducible mixture provide one or more beneficial characteristics.

Abstract: A submerged combustion melter having a plurality of side walls, a bottom wall adjacent the side walls, and a top wall adjacent the side walls, the walls collectively enclosing a melting chamber, and the bottom wall forming a plurality of openings, each of which is adapted to receive a submerged combustion burner. Each of the submerged combustion burners is positioned at least 4 inches from the side walls, at least twice as far apart from each other as the distance between the submerged combustion burners and the side walls, and less than or equal to about 20 inches apart.

Abstract: An indirect-fired gas turbine power plant comprises a compressor; a turbine mechanically coupled to the compressor; a furnace; a heat exchanger inside the furnace and fluidly coupled at an inlet end to the compressor and at an outlet end to the turbine; and means for forming a gas barrier around a portion of the heat exchanger to impede combustion products from contacting the heat exchanger. Such means can be a plurality of gas discharge manifolds located around a portion of the heat exchanger. The manifolds can be coupled to heated working gas exhausted by the turbine.

Abstract: A glass-melting furnace (10) has an upstream end (6), a downstream end (8), and a roof (22). The upstream end is positioned upstream of the downstream end. A charger (32) is provided to supply glass-forming material (30) to the upstream end of the furnace. At least one burner (34) is provided to supply heat to the glass-forming material at the upstream end of the furnace. An exhaust (60) is in communication with the downstream end of the furnace, with the exhaust being positioned downstream of the at least one burner.

Abstract: During the heating of glass melting furnaces having a combustion chamber with regenerators for preheating oxidation gases, with port necks that open into the combustion chamber, with primary burners and with secondary burners that are installed in a cascade arrangement relative to the primary burners, the secondary burners are operated as cascade burners with a relatively low proportion of the fuel, the secondary fuel. Flames are thereby created in over- and sub-stoichiometric conditions and the flame gases formed are mixed with one another so that the complete combustion process in the combustion chamber is more or less stoichiometric. The secondary fuel is supplied by the secondary burners to a step, installed in the port neck.

Abstract: A retrofit technology for air-fuel fired, vertical glass furnace for oxygen firing or boosting to provide additional heat to the process to increase furnace production capacity. The additional firing using oxygen is strategically controlled to enable enhanced radiation from oxygen flame for the spheroidizing process without negative effects on the overall process. With proper implementation, an increased production from 50% to 200%, depending on the size of the spheres, can be achieved while maintaining acceptable product quality. Processes in accordance with the present invention can be performed using one of a number of methods of oxygen boosting.

Abstract: The aim of the invention is to develop a hot rolling unit, comprising at least one continuous casting unit (1) with a post-arranged furnace (4), followed by a roughing stand (5) and, over a strip edge guide, a soaking furnace (15) and finishing train, such that downtime is reduced to a minimum level and even during said downtime, as well as in planned cases of withdrawal of pre-strip material, the pre-strip (14), behind the roughing stand in the soaking furnace, can be separated off from the normal rolling cycle.

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: A oven conveyor system is disclosed herein. In use, items to be heated are placed in contact with a hearth, and then moved across the hearth by the conveyor. The conveyor system allows the items to maintain contact with the hearth while being conveyed. A large volume of items may be heated while still obtaining the beneficial heating characteristics of a hearth-type oven.

Abstract: A multiple hearth furnace comprises at least one cleaning lance inlet port (52, 54) radially leading into one of its hearth chambers (24). A cleaning lance assembly (40′, 40″) includes an elongated mount (42) and at least one cleaning lance (48, 50) slidably mounted on the elongated mount (42). Each cleaning lance (48, 50) is connected to a cleaning fluid distribution system (56) and comprises at least one cleaning nozzle (58, 60). It can be sealingly introduced through the lance inlet port (52, 54) along a radial trajectory into the hearth chamber (24) by moving it along the elongated mount (42). The at least one cleaning nozzle (58, 60) is capable of directing a jet of cleaning fluid onto a rabble arm (34) positioned in a cleaning position in the vicinity of the radial trajectory when the cleaning lance (48, 50) is slidably moved along the elongate mount (42).

Abstract: A glass-melting furnace (10) has an upstream end (6), a downstream end (8), and a roof (22). The upstream end is positioned upstream of the downstream end. A charger (32) is provided to supply glass-forming material (30) to the upstream end of the furnace. At least one burner (34) is provided to supply heat to the glass-forming material at the upstream end of the furnace. An exhaust (60) is in communication with the downstream end of the furnace, with the exhaust being positioned downstream of the at least one burner.

Abstract: A glass feeder comprises an enclosed chamber through which molten glass can pass, and passing through each side wall into the chamber at least one burner comprising first and second burner head means for combusting oxidant and fuel within said chamber so as to generate flames which extend in axially opposite directions along each side wall, adjacent and parallel to the side walls and adjacent the surface of the molten glass.

Abstract: A oven conveyor system is disclosed herein. In use, items to be heated are placed in contact with a hearth, and then moved across the hearth by the conveyor. The conveyor system allows the items to maintain contact with the hearth while being conveyed. A large volume of items may be heated while still obtaining the beneficial heating characteristics of a hearth-type oven.

Abstract: Methods and apparatus for producing fused silica members having high internal transmission are disclosed. The apparatus and methods are capable of producing fused silica having internal transmission of at least 99.65%/cm at 193 nm.

Abstract: The invention provides a method and apparatus for charging a raw material and a carbonaceous material, in which a reduced product generated on a hearth can be quickly melted for reliable separation into a metal and slag, and the metal and the slag can be easily discharged out of a furnace as individual small agglomerates. With the charging method and apparatus, when charging the raw material and the carbonaceous material onto the moving hearth of the moving hearth furnace, the carbonaceous material is first charged onto the moving hearth to form a carbonaceous material layer thereon. The raw material or a mixture of the raw material and a carbonaceous material is then charged onto the carbonaceous material layer to form a raw material layer thereon. A projection is then pressed against the raw material layer from above, thereby forming a plurality of recesses in the surface of the carbonaceous material layer.

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.

Abstract: This apparatus is a furnace for heating molten material which employs oxygen-fuel burner assemblies. Preferably, the assemblies are submerged in the molten material. They are water cooled top down units with burner nozzles being off-set from the supply column. The apparatus utilizes one or more burners for each top down supply column. The supply column and attached burners can be rotated or moved in a manner to avoid the open chimney effect seen with fixed air-fuel burners of the prior art. These burners with an off-set nozzle like the letter L are rotated at high speed or oscillated to distribute the combustion in the form of gas bubbles or a gas curtain. In another embodiment, the oxy-fuel burners are not submerged. The nozzles are aimed at unmelted batch or the upper surface of the molten material for controlled splashing.

Abstract: The invention provides a method and apparatus for charging a raw material and a carbonaceous material, in which a reduced product generated on a hearth can be quickly melted for reliable separation into a metal and slag, and the metal and the slag can be easily discharged out of a furnace as individual small agglomerates. With the charging method and apparatus, when charging the raw material and the carbonaceous material onto the moving hearth of the moving hearth furnace, the carbonaceous material is first charged onto the moving hearth to form a carbonaceous material layer thereon. The raw material or a mixture of the raw material and a carbonaceous material is then charged onto the carbonaceous material layer to form a raw material layer thereon. A projection is then pressed against the raw material layer from above, thereby forming a plurality of recesses in the surface of the carbonaceous material layer.

Abstract: A process for manipulating workpieces, which are to be carburized, wherein the workpieces or workpiece magazines that are to be deposited on pallets are loaded in several rows, corresponding to a predefined number of rows of workpieces, into a rotating hearth furnace and, after carburization, are removed from the rotating hearth furnace and fed to a hardening press, exhibiting a predetermined number of press stations, and wherein on each pallet are deposited a number of workpieces or workpiece magazines, said number corresponding to the number of press stations. For better utilization of the capacity of the rotating hearth furnace and the hardening press, the pallets in the rotating hearth furnace are arranged in such a number of rows that the number of press stations is a divisor of the number of workpiece rows.

Abstract: A fused silica refractory material made from quartz grains and a method of making the material which contains calcium oxide binder in an amount less than one weight percent. The reduction in calcium oxide binder prevents the degradation of fused silica refractory bricks in furnace environments containing alkali vapors, such as in oxygen-fuel fired glass furnaces. The invention also includes a method of preventing the degradation of silica refractory material by alkalis.

Abstract: The invention relates to a charging device for creating superimposed layers of fine-grained bulk material on a rotating hearth (2). For each layer of bulk material to be charged, said charging device comprises a discharge hopper (22) having an outflow slot (36) and a discharge roller (42) positioned ahead of each outflow slot (26). Said outflow slot (36) and discharge roller (42) extend essentially at a right angle to the direction of rotation of the rotating hearth and the discharge roller (42) has a drive (44), the rotational frequency of which can be controlled.

Abstract: This apparatus is a furnace for heating molten material which employs oxygen-fuel burner assemblies. Preferably, the assemblies are submerged in the molten material. They are water cooled top down units with burner nozzles being off-set from the supply column. The apparatus utilizes one or more burners for each top down supply column. The supply column and attached burners can be rotated or moved in a manner to avoid the open chimney effect seen with fixed air-fuel burners of the prior art. These burners with an off-set nozzle like the letter L are rotated at high speed or oscillated to distribute the combustion in the form of gas bubbles or a gas curtain. In another embodiment, the oxy-fuel burners are not submerged. The nozzles are aimed at unmelted batch or the upper surface of the molten material for controlled splashing.

Abstract: In the manufacturing of high melting point glasses with volatile components, in particular of glasses from the group of boron glasses and borosilicate glasses, a furnace is provided that has a superstructure, fossil fuel burners, and a melting tank. In front of a conditioning zone and a throat leading to an extraction zone, a step-shaped raised area in the bottom is provided which is formed continuously over the complete width of the melting tank. In order to suppress segregation or, respectively, phase separation, to protect the furnace construction materials and to enable problem-free operation, a temperature of at least 1600.degree. C.

Abstract: In a process for manufacturing glass in a furnace a glass charge in solid form is introduced into a furnace-charging zone at an upstream part of a furnace. The glass charge is moved from the furnace-charging zone to a zone for removing the combustion smoke from the furnace downstream from the furnace-charging zone. The glass charge is moved from the zone for removing combustion smoke to a charge-melting zone downstream from the furnace-charging zone and located substantially in a middle of the furnace and heated by at least one burner. The glass charge is moved from the charge-melting zone to a charge-refining zone downstream from the charge-melting zone. The glass charge is brought to a desired temperature and viscosity in the charge-refining zone. The glass charge is removed from the furnace after the glass charge has been brought to the desired temperature and viscosity. The glass charge, after it has been removed from the furnace, is moved into a feed channel of glass-forming machines.

Abstract: A method and apparatus involving combustion for melting glass. The fuel and oxidizer of the combustion are both supplied in such a way as to spread out the fuel/oxidant contact over time and to increase the volume of the contact. This limits the temperature peaks and reduces No.sub.x emissions. The invention also relates to the glass furnace which implements the method.

Abstract: A combustion assembly adapted for a furnace is provided. The assembly includes an axis comprising at least one pair of burners having axes. An oxidant lance is arranged between the burners of the pair and has a lance axis. A source of oxidant is connected to the burners and to the lance. The combustion assembly can provide uniform heating of a charge of glass in a furnace.

Abstract: Method of heating the charge of a glass furnace in which at least one burner is placed in a wall of a furnace so as to heat the bath of glass, characterized in that at least one assembly consisting of a first and a second burner which are fed with fuel gas and with oxidizer gas containing at least 50 vol. % of oxygen is arranged in one of the walls of the furnace at a distance (D) at least equal to approximately 3 meters from each other, in that an oxygen lance is arranged between the first and second burners, the first burner, the second burner and the lance forming a combustion assembly and in that from approximately 30 vol. % to approximately 80 vol. % of oxidizer gas is sent into the lance and from approximately 20 vol. % to approximately 70 vol.

Abstract: A furnace for melting and refining E glass comprises a melting and refining tank for melting and refining the glass batch materials into glass and a forehearth, downstream of the tank, for further refining the glass and delivering the glass to fiberizing means. The melting and refining tank is heated with oxygen fired burners. The oxygen fired burners in the melting and refining tank are located in the sidewalls at the upstream end of the tank and extend for about one-third the length of the tank. In one embodiment, burners are also located in the upstream end wall. This arrangement of the oxygen fired burners at the upstream end of the melting and refining tank moves the melter hot spot upstream for better refining of the glass and enables the furnace to produce a higher output of glass than can be obtained in a conventional E glass furnace of the same size.

Abstract: Regenerative glass melting furnace of the type having a batch section where glass is melted, a port neck where combustion air is introduced, and burners supplied by fuel inlet nozzles in the floor, the roof, and the lateral walls of the port neck.

Abstract: A gas-lance apparatus and method for injecting a rate-enhancing gas between a flame and a thermal load to augment combustion of fuel undergoing combustion in the flame. A fan-shaped main jet is introduced between the flame for producing a low pressure field of the rate-enhancing gas between the flame and the thermal load. The low pressure field deforms the flame into the shape of the main jet and draws the flame toward the thermal load. The main jet decays along its length due to entrainment of combustion-environment gas in the main jet. In order to delay such decay, a fan-shaped booster jet of rate-enhancing gas is introduced between the main jet and the thermal load. The booster jet has a higher velocity than the main jet and is positioned adjacent to the main jet.

Abstract: A gas-injection lance, burner, and method for use in a high temperature heating system which provides a nonaxisymmetric flow of a reaction-rate enhancing gas in sufficient proximity to the flame of the system, which extends over the surface to be heated, to create an aerodynamically rreduced pressure field sufficient to deform the flame and displace it in the direction of the surface to be heated. The present method provides substantially enhanced heating with the virtual elimination of hot spots.

Abstract: Method of preparing a melt for the production of mineral wool wherein suitably composed raw material and coke are fed into a preheating zone in the upper portion of a shaft furnace and are caused to descend down through the oxidation zone in which air is introduced to effect a combustion of the coke and to heat the raw material to a temperature not exceeding 1000.degree. C., and wherein the actual melting is effected by plasma heating in the lower portion of the shaft furnace where which the melt formed is discharged.

Abstract: A device for heating open melting baths, especially galvanizing baths, enameling baths, lead coating baths, metal baths, and glass baths, and the like, in tubs, or vats or tanks, wherein an inert gas is circulated through components of the open baths which are closed toward the gas side which are in the form of shafts, and through a heater, whereby the gas is introduced into the fluid of the bath into vertical shafts, arranged on each longitudinal and/or end side of the tub, or vat or tank, the gas then bubbling through the fluid and being withdrawn through a withdrawal channel positioned above the shafts. There is provided at least one ceramic partition extending into the fluid, which partition forms at least part of the vertical shafts, and having at least one bore or a slot the upper end of which is in communication with the gas inlet conduit and the lower end of which opens into a pertaining vertical shaft or has provisions for directing the gas into the shaft.

Abstract: A device for heating open melting baths, especially galvanizing baths, enameling baths, lead coating baths, metal baths, and glass baths, and the like, in tubs, or vats or tanks, wherein an inert gas is circulated through components of the open bath which are closed toward the gas side, and through a heater, whereby the tub, or vat or tank includes at each longitudinal and/or end wall a plurality of conduit means, such as pipes, for introduction of the gas into the bath and whereby the gas is withdrawn above the conduit means through a draft flue at the edge of the tub, or vat or tank, which draft flue includes a vertical partition immersed in the bath. The device includes means for communicating a warm gas receiving means with the container for the melting bath which communicating means includes at least one ceramic block including passage means for communicating the warm gas receiving means with the container.