Abstract: An arrangement for operating an arc furnace with two vessels for making steel. Enough liquid raw iron is added to account for 70% of the total starting metallurgicals. The supply of electricity to one of the vessels is discontinued but not to the other vessel. The injection of oxygen through a lance accompanied by the addition of sponge or coolant and lime, is carried out in one vessel while an electric-arc furnace phase is carried out in the other vessel, whereby additional sponge or coolant is melted with less oxygen and additional lime or coal is added. Electrodes are mounted on an arm and can be pivoted over either vessel as desired.

Abstract: The combined installation comprises at least one metal production unit (II), including at least one, and typically a series of metal production or treatment units (1-6), and at least one air gas separation unit (III) including at least one outlet for at least one air gas (14-18), the units being supplied with compressed air with a low water vapor content by a common compressed air production unit (I), and with at least one of the gas outlets (14-18) from the separation unit (III) connected to at least one of the devices (1-6) of the production unit, to supply the latter with gas.

Abstract: In a filter dust melting furnace, the waste gases occurring in the interior (9) of the furnace are conducted outward through a waste-gas line (5) in the furnace top. Provided in the course of the waste-gas line is a quench (20) for the abrupt cooling of the waste gas by cold quenching air acting on it. To prevent deposits in the waste-gas line, the quench (6) is arranged in the section of the waste-gas line (5) which directly adjoins the furnace vessel (1) and extends essentially vertically, and means are provided for cooling the quench and the section of the waste-gas line (5) located downstream after the quench.

Abstract: A process is provided for the treatment of waste gases, dust and vapor from a closed arc furnace disposed in a furnace vessel. The furnace vessel contains a charge column, a metal melt and slag arranged in the lower portion of that vessel. The charge column, the metal melt and the slag are smelted in the furnace vessel. The gases, dust and vapors are guided in a direction opposite to the natural flow through the charge column in the furnace during the smelting. The gases, dust and vapor are then brought into contact with the melt and the slag after leaving the charge column. The gases, dust and vapors are then removed from the arc furnace in a region between the upper and lower portions of the vessel.

Abstract: A double furnace installation having two arc furnaces connected via a line, a power supply, a device for charging material, and an arrangement for extraction and purification of gas is operated by connecting a first one of the furnaces with the power supply for melting a charge located therein, isolating a second one of the furnaces from the power supply, charging the second furnace with charging material, and closing the second furnace with a cover. Flue gas generated during a melting phase of the first furnace is sucked therefrom and introduced into the second furnace through a first interior bay region of the second furnace. The flue gas entering the second furnace in this manner passes substantially horizontally through the charging material in the second furnace because it is sucked therefrom through a second interior bay region disposed diametrically opposite the first interior bay region.

Abstract: For heating sponge iron to temperatures of about 850.degree. C. without substantial oxidation losses, there are provided at least two separate preheating stages at different temperatures, to which the sponge iron is successively fed and in which the temperature and the gas atmosphere are respectively individually controlled in such a way that a chemically neutral gas atmosphere is set in the first preheating stage at the lowest temperature and a reducing gas atmosphere is set in the last preheating stage at the highest temperature. The hot gas for the preheater is obtained at least in part from the waste gas from the melting furnace, to which the preheated sponge iron is fed.

Abstract: A fluidized bed direct steelmaking plant for reducing raw iron ore fines and directly producing an iron product in a virtually closed gas system comprises an ore feed assembly, a multi-stage reactor assembly with a compacting assembly, a gasifier/smelter assembly, and, a reducing gas assembly. Reducing gases utilized in the plant are produced from processed offgas from said smelter assembly and recycled reducing gases from said reactor assembly. The processed offgas is 100% utilizable as reducing gas by balancing the reduced iron ore between the gasifier/smelter and compacting assemblies. The iron product is refinable into steel with a standard available refining assembly, such as a ladle or basic oxygen furnace, for removal of impurities prior to casting.

Abstract: This invention provides a method and appratus whereby steel of various compositions may be produced from iron ore and coal through a series of stages without the intermediate production of liquid iron. A reforming reactor receives top gases from the steel making reactors, and converts them to high reduction potential gases which are returned to the steel making reactors. The iron ore and reductants, such as coal, are charged to a controlled atmosphere reactor which may be an inclined rotary cylindrical shaft. From the controlled atmosphere reactor the charge is moved to a potential shift reactor which is inclined or vertical and encounters increasing heat and rising gases for converting the carbonised sponge into a semi-molten state. The charge then passes to a high temperature reactor where it encounters the reducing gases from the reforming reactor and preheated oxygen to create temperature in which steel is made.

Abstract: A smoke suction duct of an electric furnace is constructed as a separate member from other exhaust duct portions and other devices and is supported to be rotatable about an axis of the duct. Further, the smoke suction duct is either alternately turned to right and left or continuously turned in one direction by a duct turning device. Since accumulating dust is raised to an upper portion of the smoke suction duct where an exhaust gas flow has a high velocity due to rotation of the smoke suction duct and is pushed toward a combustion tower by the exhaust gas flow, dust is advantageously prevented from accumulating on a bottom of the smoke suction duct.

Abstract: A smelting unit having a furnace vessel (11) which is mounted on a furnace rocking cradle (13) and which can be closed by a cover (12), and bar electrodes (28) which can be lowered into the furnace vessel (11) and which can be raised and lowered by means of electrode lift devices (30), in which the electrode lift devices (30) are carried by a portal assembly (31). In a lowered position the portal assembly (31) lies on a support holder (33) of the vessel substructure (14) or the furnace rocking cradle (13) respectively and in that position can be tilted with the furnace vessel (11). It can be released from the furnace vessel (11) and pivoted to the side by a lift post (43) of a stationary lifting/pivoting mechanism (40). When the unit has two vessels which are arranged side-by-side, the bar electrodes can be associated alternately with one vessel or the other by means of the lifting/pivoting mechanism (40).

Abstract: The inside of the metallurgical container is connected to a fan (105) through an exhaust duct (102). An additional gas is introduced in the intake part of the fan (105) preferably through the duct (102). The additional gas introduction flow is regulated in such manner that the gas pressure in the intake part of the fan (105) is maintained at a fixed value, via an adjusting valve (108) preferably placed in an additional duct (107) connected to the exhaust duct (102). A control system (110) regulates the opening and closing of the adjusting valve (108) in such manner as to maintain the gas pressure in the intake part of the fan (105) constant.

Abstract: In a smelting plant including two melting furnaces which are arranged in juxtaposed relationship and which are operated alternately, wherein the furnace gases which are produced in the melting process are respectively introduced into the other melting furnace for the purposes of preheating the charging material, associated with each melting furnace is a shaft which is loaded with charging material, and the waste gases from the furnace which is in the melting mode of operation are introduced from the shaft, after charging of the other furnace, through the cover of the other furnace, and are removed from the shaft thereof. That procedure, throughout the entire smelting operation, permits preheating of charging material and filtration of the furnace gases when they are passed through the charging material.

Abstract: A method for exhausting gases or fumes from a metallurgical container through a duct connected to the intake of a pump while introducing an additional gas stream into the pump is described. The additional gas stream ensures a constant gas pressure at the intake portion of the pump.

Abstract: For the metallurgical treatment of a molten metal bath (1) in a metallurgical smelting and refining vessel (3), additive substances (43) which are capable of flow, in particular lime, are supplied in a granular to dust state, at least during a part of the refining phase, to the upper region of the inward side (15') of the vessel wall (11), distributed around the periphery thereof. At the vessel wall (11) the additive substances (43) form a barrier or protective layer which reduces the energy losses and increases the service life of the vessel (3).

Abstract: A plant for the production of molten metals includes a melting vessel in whose wall burners and optionally oxygen-containing-gas feeding ducts are installed and on whose upper end a charging device as well as a gas evacuation duct receiving the offgases forming enter.In order to enable the continuous charging of the melting vessel by avoiding any unintentional escape of gas from the melting vessel, both the gas evacuation duct and the charging means run into the upper end of the furnace shaft laterally and approximately diametrically opposite each other. The charging means projects into a charging opening brushed over by a gas curtain and an intake chute for charging material is provided below the charging opening in a manner directed towards the center of the furnace shaft.

Abstract: Temperature maintenance and metallurgical treatment furnace for a metal in liquid state, comprising a closed container for liquid metal provided with a burner of the oxygen-combustible type, a porous plug for the bottom of the container for injecting a neutral stirring gas, and openings for the introduction and/or the removal of metallurgical treatment products. The container is in the form of an insulated enclosure which is rockable about a support axis, with two ducts with vertical component, one which is in the form of a chimney opening in the enclosure close to the vault of the enclosure and serving for the introduction of liquid metal and metallurgical treatment products, the other which is in the form of a chute opening at the level of the bottom of the enclosure and in which the upper opening is in position of liquid metal removal in a rocked position of the enclosure. The burner is mounted in the vault of the enclosure.

Abstract: An improved FIOR processing plant and method for reducing raw iron ore fines into a 90+% metallized briquette product utilizing a multi-stage fluidized bed reactor in which the reducing and fluidizing gases are the products of partial combustion of methane with oxygen, the gases being introduced into an intermediate zone of the reducing tower above the stage or stages where final metallization occurs. Said processing plant including an ore preparation and feed assembly, a mutli-stage reactor assembly, a briquetting assembly, a recycle and fresh reducing gas assembly, and, a heat recuperation assembly.

Abstract: The present invention relates to an overall direct smelting process which provides for separating the carburization function from the heating function to permit separate control of the individual functions. One embodiment of the smelting reactor is divided into a carburization/smelting section and a heating section with a substantial recirculation of the molten product from the heating section back to the carburization/smelting section. The heating section also serves as a slag/metal separation section. Carburization is achieved by injection of solids (fine coal mixed with slagging agents), where desired. Gas generating solids or inert gases are injected into a lift pipe to provide a motive force for circulation of the molten metal. The circulation rate through the system is a function of the injected solid composition, the mass flow rate of the solids injected into the lift pipe and the lift pipe geometry.

Abstract: The furnace comprises two chambers, a closed well melting chamber and a main heating chamber. The furnace includes a hot gas duct connecting the chambers, the hot gas duct having a damper to control the gas flow between chambers in accordance with the respective condition of each chamber. The furnace is designed to have an efficient liquid metal flow by sloping the floor.

Abstract: An improved thermite reaction containment vessel and method of using the same includes a filter assembly which serves to filter the gases evolving from the thermite reaction and reduce the amount of smoke, fume and the like by-products emitted. In one preferred embodiment the filter assembly comprises a primary filter and a secondary filter. An air gap may be provided between the primary and secondary filter so as to provide additional cooling of the gases before they enter the secondary filter. The invention further provides a remote electrical ignition system which is capable of igniting thermite reaction materials without the use of a starting material. The ignition system may include an ignition fuse having an aluminum core and an outer coating comprising palladium and ruthenium or hot wire.

Abstract: There is described a mill for the production of steel from liquid and solid charging substances. It includes a coking plant, a blast furnace plant, a converter steelworks, and a plant for the direct reduction of iron ore. The converter steelworks is charged with molten pig iron from the blast furnace and with scrap as well as with sponge iron from the direct reduction plant. The reduction gas is composed of converter offgas, top gas and blast furnace gas. In order to avoid coal deposits in the direct reduction plant and to improve the composition of the reduction gas, the coke oven gas component is subjected to fractionation by alternating pressure adsorption so as to increase its portion of hydrogen and to lower its portion of hydrocarbons.

Abstract: A reactor for iron making having an upper gas blowing nozzle, a lower gas blowing nozzle, and an iron scrap charging inlet. A vertical shaft is installed directly above the inlet at the top part of the reactor. A mechanism is provided in the lower end of the vertical shaft for controlling charging of the iron scrap to the reactor. A by-pass tube is connected between the top part of the reactor and a gas inlet in the vertical shaft directly above the mechanism for controlling the charging of iron scrap and permits exit of high temperature exhaust gases from the reactor and introduces the exhaust gases to flow through the iron scrap in the vertical shaft to pre-heat the same. Structure is provided in the by-pass tube for introducing oxygen gas or air into the high temperature exhaust gases to react therewith and generate further heat. The structure can comprise a nozzle.

Abstract: In a method of producing a mixed gas from a process gas of a continuously working gasifier and a discontinuously incurred off-gas of an oxygen blowing converter, the off-gas of the refining process having the lower pressure is sucked into the process gas of the gasifier with the higher pressure via a gas jet ejector. The process gas serves as power gas, and subsequently the mixed gas is dedusted. A plant for producing steel includes a plant for recovering pig iron formed by a reduction shaft furnace and a melt-down gasifier, and at least one oxygen blowing converter for converting the pig iron into steel. The reduction shaft furnace has a process or top gas duct system, the converter has a converter off-gas duct, and an ejector connects both, the converter off-gas thus being feedable into the top gas duct system to form the mixed gas. Common dedusting and washing devices are provided for the mixed gas and safety devices for preventing oxygen from entering into the mixed gas.

Abstract: A furnace for firing a non-precious metal paste including organic material, comprising a furnace enclosure, tube-like in shape, having a definable length. First and second ends of the furnace enclosure is open forming an entrance and exit, respectively. A cross-section across the length of the furnace enclosure has a flat base, a first and second vertical wall at each end of the flat base, and a roof, the shape of the roof being essentially the upper half of an ellipse. The interior chamber of the furnace is divided across the length of the furnace enclosure into a burnout zone and a firing zone, the entrance leading to the burnout zone, and the exit being nearest the firing zone. A sparging element distributes a mixture of an inert gas and at least one other gas within the burnout zone, wherein the other gas supports burnout of the organic material.

Abstract: A process and apparatus for producing steel from scrap. A cupola furnace is provided with a layer of coke in the vicinity of the tuyeres of the furnace, with scrap to be melted being supplied upstream of the layer of coke and molten scrap passing through the layer of coke to a converter located downstream of the furnace. The molten scrap is refined in the converter with oxygen, thereby producing a CO-rich converted waste gas, which is supplied to the coke layer and burned in the vicinity of the tuyeres.

Abstract: A method of producing iron from finely divided iron oxide comprising the steps of: mixing iron oxide or iron ore fines with finely divided coal and a binder to form a mixture, agglomerating the mixture by compacting, pelletizing, or briquetting the mixture to form agglomerates or pellets, introducing the pellets to a rotary hearth furnace to prereduce the iron in the pellets, introducing the prereduced pellets into a smelting reduction vessel as the metallic charge constituent, introducing particulate carbonaceous fuel and oxygen to the smelting reduction vessel through the bottom of the vessel to react with the melt or bath within the vessel, reduce the iron to elemental iron and form an off gas containing CO and H.sub.2 introducing the off-gas into the rotary hearth furnace as process gas to prereduce the pellets therein, and drawing off the hot metal from the smelting reduction vessel.The prereduced compacts are preferably discharged from the rotary hearth furnace at a temperature of at least 1000.degree.

Abstract: An improved apparatus for reactor iron making has a furnace body to melt raw material, typically as scrap, a shaft to heat the raw material, and a raw material supply bucket, these three components being arranged vertically, with an exhaust gas combustion tower positioned close to the shaft.Raw material is supplied to the shaft with this apparatus by the bucket, and, after being heated by exhaust gas from the furnace body, the raw material is charged into the furnace body by the opening/closing operation of a shaft damper and a furnace body cover.Exhaust gas is introduced from the furnace body into the combination tower, air is supplied in stages, the temperature of the gas is gradually raised through combustion of CO, and the gas is used to heat the raw material in the shaft.

Abstract: In a method of producing a mixed gas from a process gas of a continuously working gasifier and a discontinuously incurred off-gas of an oxygen blowing converter, the off-gas of the refining process having the lower pressure is sucked into the process gas of the gasifier with the higher pressure via a gas jet ejector. The process gas serves as power gas, and subsequently the mixed gas is dedusted. A plant for producing steel includes a plant for recoverng pig iron formed by a reduction shaft furnace and a melt-down gasifier, and at least one oxygen blowing converter for converting the pig iron into steel. The reduction shaft furnace has a process or top gas duct system, the converter has a converter off-gas duct, and an ejector connects both, the converter off-gas thus being feedable into the top gas duct system to form the mixed gas. Common dedusting and washing devices are provided for the mixed gas and safety devices for preventing oxygen from entering into the mixed gas.

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

Abstract: Method of reactor iron making without using electric power in the reactor. Iron scrap and a solid non-petroleum carbonaceous material, i.e., powdery coal or coke, are continuously charged from above into molten iron in the reactor with a space over the molten iron. The carbonaceous material is charged by injecting it with a stream of nitrogen or air. Oxygen gas is simultaneously blown into molten iron below its surface so as to stir it and oxidize the carbonaceous material mainly to CO and blown into the space over the iron to oxidize the CO to CO.sub.2. The amount of oxygen is increased as the amount of molten iron increases. The iron scrap melts from the heat generated by the oxidation. The high temperature exhaust gas is used to preheat scrap to be charged. When the amount of molten iron reaches a predetermined level, it is tapped off until a lower predetermined level is reached. The above steps are repeated. Twin reactor iron making can use the method.

Abstract: A method of measuring the water content of charge materials in a shaft furnace, such as a blast furnace, wherein a known quantity of material is introduced into the shaft furnace, the gases emerging from the throat of the shaft furnace are analyzed; and the results of this analysis are used to calculate the value of the water content of the charged material.

Abstract: The gasification of solid carbonaceous materials such as coal is achieved by directing a stream containing the carbonaceous materials onto a high temperature hot spot which has been formed on the surface of a bath of molten iron by oxygen jets blown thereagainst, the stream containing the carbonaceous materials emanating from a non-submerged, top-blowing lance, the oxygen jets emanating from the same lance or from different lances, and the bath of molten iron being contained in a reactor such that its total volume remains essentially constant.

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: Apparatus for preheating scrap material, e.g. scrap metal, comprises heaters, such as air preheaters, scrap containers and air or gas conduits for conveying heated gas from the heaters to the scrap container(s) and back from the scrap container(s). The apparatus is characterized in that the conduit to the scrap container(s) is provided with valve means for diverting the flow of hot air or gas to the container(s), for example during replacement of container(s).

Abstract: A process and apparatus for continuous copper smelting, slag conversion, and production of blister copper in the same furnace by enriched oxygen containing gas injection.

Abstract: A refractory lined melting furnace particularly suited for separation of non-ferrous metals with embedded or attached ferrous components, includes a casing or body pivotally mounted and tiltable by means of fluid operators. The interior is divided by two vertical walls into a combustible waste burning portion for the generation of combustible gases to assist in heating the furnace, and a melt chamber into which a variety of metallic waste can be charged for melting. A conventional fire burner is supplied to the melt chamber. The temperature of the melt chamber is raised to the melting point of the metallic waste material having the lowest melting point, e.g. aluminum, and when the aluminum is melted, the aluminum runs through drainage apertures into a liquid metal holding chamber provided on the floor of the melt chamber. When the molten metal has drained, the furnace is tilted rearwardly to discharge the remaining scrap out through rake-out doors at the rear of the melt chamber.

Abstract: The invention concerns a process for the recovery of combustible gases in an electrometallurgy furnace comprising an external metal casing (1) and an internal refractory lining (2), in which at least one oxidized compound is reduced by means of carbon, the various components being introduced into the furnace in the form of a divided charge (6) (A) which moves progressively downwardly towards the reaction region (C), passing through a sintering region (B). The combustible gases produced in the reaction region are collected by suction, by means of a plurality of apertures (8) provided in the external metal casing (1) and the internal refractory lining (2) and disposed at a level corresponding to the lower portion of the divided charge (A) and before it passes into the sintering region (B).

Abstract: Apparatus for melting relatively large floating units of metal scrap in a molten melting media or medium, the units having oxide films and solid, liquid and gaseous inclusions. After the units are charged into a melting medium, layers of freshly melted metal are presented to the molten media. The apparatus includes a bay for heating the molten media and means for pumping the media from the heating bay to a circular bay for receiving the large units of metal scrap. Located in the circular bay is a rotor means for moving the media therein at a velocity sufficient to sweep away the surface and insulating layers of the floating units in a rapid manner such that new metal is rapidly and continuously exposed to the melting media without the floating units being submerged in the media. A third bay is included for collecting skim material from the molten media leaving the circular bay.

Abstract: A plasma melting furnace includes a cover and a melt container. Through its side wall plasma burners arranged so as to be inclined towards the furnace axis are guided. A main flue gas conduit equipped with a draft regulating damper is connected to the cover and a separate discharge means for flue gases from other furnace openings is additionally provided. In order to provide an efficient discharge of flue gases and reaction gases forming as well as dusts and fumes without straining the furnace hall and the environment, and to maintain a protective gas atmosphere in the furnace interior safely during all the necessary working cycles, the separate discharge means is designed as a downwardly open channel. The channel is peripherally attached to the outer side of the container in the region of the upper rim of the melt container.

Abstract: An apparatus for the handling of converter gases, especially the storage thereof, comprises a hood which fits over the mouth of a steel making converter and is connected by a duct and blower to a storage vessel. According to the invention, between the blower and the storage vessel, a cruciform junction is provided with the lower upwardly extending stretch being connected to the discharge side of the blower, the upper upwardly extending stretch being connected to a flaring pipe, one horizontal stretch being connected to the storage vessel and the other horizontal stretch to a bypass to the flaring pipe. Valves are provided for controlling the flow such that only the valuable gas is stored.

Abstract: A reactor for reclaiming lead and other metals from scrap batteries which includes two reaction chambers with the upper end of one chamber having a scrap feeding mechanism and at least one burner to melt lead and other metals and ignite organic materials. The chambers are interconnected at their low points for gravity flow of molten metal into a sump. The other reaction chamber is connected with an exhaust system and provided with baffles to retain gases for a predetermined time. The sump includes a tap for slag and a siphon discharge for molten lead. Also, air or oxygen may be introduced into the reaction chambers and/or the sump.

Abstract: A system for generating power with the top pressure of a plurality of blast furnaces by leading a gas from the top of the furnaces into turbines, corresponding in number to the furnaces, to convert the pressure of the gas into rotational energy and generate power by a generator coupled to the turbines. The turbines connected to the furnaces by main gas channels individually are aligned with their rotor shafts connected together into a single shaft which is connected to the generator. Preferably each pair of the adjacent turbines are arranged with their intake ends positioned in the center of the arrangement so that the gas flows toward the exhaust ends at both sides, or with their intake ends positioned at both sides to cause the gas to flow toward the exhaust ends in the center. The single shaft connecting the pair of turbines together has no intermediate bearing between these turbines.

Abstract: A lance for use in a basic oxygen vessel is provided with a fluid cooling arrangement which is mounted directly on the lance structure and which is vertically adjustable therewith to provide a fluid spray which effectively enables and ensures cooling and suppression of the exiting gas before it contacts the hood and moves into the ducts of the hood structure.

Abstract: A batch type pipe burnout oven is provided with improved pollution control and heat recovery features. The oven is elongated with an end opening for introduction of a movable support or cart with pipe supported thereon. The oven is brought to burnout temperature faster than prior art ovens and an improved system is provided for pollution control by incineration of hydrocarbon fumes together with recovery of heat which results in superior fuel economy. The oven is provided with a pair of oppositely positioned plenums along the sides thereof which supply heated air in large volume and high velocity through a plurality of nozzle slots to the pipe-containing chamber and are themselves supplied from a recirculation burner chamber on the top of the oven. A relatively small volume of air, laden with volatile, combustible fumes, is withdrawn from the oven at a relatively low velocity by an exhaust fan.

Abstract: A process and system for recovering the top gas from a blast furnace into a gas holder without discharging the top gas into the surrounding atmosphere so as to be utilized for various purposes, thereby overcoming the environmental pollution problems and attaining the energy saving.

Abstract: In an arrangement for capturing and conducting away flue gases forming during charging of, and pouring off from, metallurgical vessels in a steel-making plant, the material to be charged and poured off is brought into and out of the operating position by a container displaceable by means of a crane. The crane trolley is designed to form a displaceable unit with a hood having a draft opening. The hood, in the operating position, covers the container and the mouth of the metallurgical vessel, and the draft opening borders on the discharge opening of a chimney so as to form a flow connection therewith.

Abstract: In a system wherein exhaust gases containing SO.sub.2 are fed to a sulfuric acid plant from multiple furnaces, including an intermittently operated furnace (such as a copper or nickel converter furnace), a method of automatically controlling the gas pressure to within a predetermined range at a point just upstream of the exhaust gas pretreating equipment at the inlet of the sulfuric acid plant so as to compensate for the fluctuation in the exhaust gas pressure resulting from start up and stopping of the operation of the intermittently-operated furnace. By this method, the disadvantages caused by large gas fluctuations, i.e., the leakage of SO.sub.2 -containing gas and the suction of excess free air can be prevented.

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 of controlling a process off-gas system by generating a model of the input to the system as a function of the gas generating inputs to the process vessel served by the off-gas system and feeding forward this flow representation as the set point for a feedback flow control loop for the downstream off-gas system fans. The feed forward signal is trimmed by a process off-gas pressure feedback loop which when applied to a TBRC off-gas system assures a minimum flow of leakage air to prevent puffing. The flow control feedback loop employs a mass spectrometer to provide on line computation of the true off-gas flow at the fans. Since the input model can be generated as a simple linear function of the SCFM of the gas generating inputs to the process, the flow control loop is operated on the same basis although it can also be operated on the basis of mass flow.

Abstract: A lance for use in a basic oxygen vessel is provided with a fluid cooling arrangement which is mounted directly on the lance structure and which is vertically adjustable therewith to provide a fluid spray which effectively enables and ensures cooling and suppression of the exiting gas before it contacts the hood and moves into the ducts of the hood structure.