Abstract: The invention relates to a method for sintering aluminium-based sintered parts which are, initially, guided with the aid of a transport system T through a de-binding area (3) before being guided through followed by a sintering area (2) and finally being guided through a cooling area (4). Inert gas atmosphere prevails in the sintering area (2), provided with an oxygen content, corresponding to a thawing point of, maximum, 40° C. The sintered parts (23) are heated to the required sintering temperature of 560-620° C., by means of convection, whereby the inert gas atmosphere is accordingly heated, flowing around said sintered parts in a corresponding manner.

Abstract: In a process for the direct reduction of particulate iron-oxide-containing material by fluidization, a synthesis gas is introduced as a reducing gas into several fluidized bed zones consecutively arranged in series. The reducing gas is conducted from one fluidized bed zone to another fluidized bed zone in counterflow to a flow of particulate iron-oxide containing material through the fluidized bed zones. In order to reduce operating costs and, in particular, the energy demand, various process parameters are varied according to the temperature of the iron-oxide-containing material in the first fluidized bed zone being adjusted to be below 400° C. (and, preferably, below 350° C.), above 580° C. (and preferably about 650° C.), or to a temperature within the range of from 400° C. to 580° C. If the temperature of the iron-oxide-containing material in the first fluidized bed zone is maintained to be below 400° C.

Abstract: An apparatus for producing reduced iron, and a compact drying method for application to the apparatus are disclosed. The apparatus comprises a pelletizer or a briquetter for mixing and agglomerating coal as a reducing agent and iron ore as iron oxide to form compacts, a dryer for drying the compacts, a circular rotary hearth type reducing furnace for reducing the dried compacts in a high temperature atmosphere, a first heat exchanger for performing heat exchange between a hot off-gas discharged from the reducing furnace and combustion air to be supplied to the reducing furnace, and coolers for cooling the hot off-gas. A second heat exchanger for heating drying air is disposed on an exit side of the first heat exchanger. The drying air heated by the second heat exchanger is supplied to the dryer to dry the compacts with the drying air which is scant in moisture. Consequently, highly efficient, stable drying in the dryer can be performed, and high quality reduced iron can be produced stably.

Abstract: A method and device for removing decay heat from a liquid metal reactor using a thermosyphon so as to cool the reactor is disclosed. The method and device of this invention uses a thermosyphon heating part in place of a conventional air separator, thus improving its decay heat removal capacity. In the method of this invention, decay heat from the reactor is absorbed at the flowing air and additionally at the evaporator section of the thermosyphon. The absorbed heat at the evaporator section is, thereafter, dissipated to the atmosphere from the condenser section of the thermosyphon. In the liquid metal reactor installed at a position between a containment and a reactor support concrete wall, the thermosyphon is installed at a position between the concrete wall and the containment vessel.

Abstract: A process to optimize the reduction process with a given quality of ore. The reduction gas 7 is analyzed by means of gas sensor 1 and is separated into two partial flows. The throughput of the partial flow which is oxidized is regulated by a regulation valve 3 and is then sent to the burner 4 where it is oxidized. The other partial flow of the reduction gas [7] is regulated by a regulation valve 2 according to the required amount of gas in the shaft and is thereafter brought to the required temperature in the heat exchanger 11 and mixed with the oxidized partial flow of the reduction gas. The gas components are determined by a gas sensor 13 and, when necessary, a gas delivery 14 is adjusted according to mathematical formulations. This makes it possible it possible to run the reduction process in the direction of its stoichiomeric optimum using a given quality of ore.

Abstract: An apparatus for producing reduced iron, and a compact drying method for application to the apparatus are disclosed. The apparatus comprises a pelletizer or a briquetter for mixing and agglomerating coal as a reducing agent and iron ore as iron oxide to form compacts, a dryer for drying the compacts, a circular rotary hearth type reducing furnace for reducing the dried compacts in a high temperature atmosphere, a first heat exchanger for performing heat exchange between a hot off-gas discharged from the reducing furnace and combustion air to be supplied to the reducing furnace, and coolers for cooling the hot off-gas. A second heat exchanger for heating drying air is disposed on an exit side of the first heat exchanger. The drying air heated by the second heat exchanger is supplied to the dryer to dry the compacts with the drying air scant in moisture. Consequently, highly efficient, stable drying in the dryer can be performed, and high quality reduced iron can be produced stably.

Abstract: An emission treatment apparatus for manufacturing plants including an inlet duct, a decantation chamber and an outlet duct. The emission treatment apparatus advantageously includes elements located inside of the decantation chamber for rendering uniform the flow of the emissions.

Abstract: In a copper flash-smelting works, forced oxidation of dust is prevented, adhesion of dust to a boiler water tube is reduced, and on-line ratio and productivity index is improved. The temperature at the WHB radiation section outlet is greatly reduced and the atmosphere within the WHB radiation section is controlled by blowing the mixed gas of nitrogen gas and air from the feed aperture established in the wall into the boiler radiation section of the waste heat boiler of the flash-smelting furnace in a copper flash-smelting works.

Abstract: A melt-reducing facility for directly producing molten iron or molten pig iron by throwing iron bearing material, carbon material and flux into furnace bodies and blowing pure oxygen and/or an oxygen-rich gas therein, wherein a waste heat boiler and a power-generating facility are connected to a plurality of furnace bodies through ducts which can be freely opened and closed, the waste heat boiler being capable of recovering by vaporization the sensible heat and the latent heat of the combustible gases generated from the furnace bodies.

Abstract: Method and apparatus for the production of prereduced iron ore, Direct Reduced Iron (DRI), or the like, in an ironmaking plant wherein the reducing gas utilized in the chemical reduction of iron oxides is generated from natural gas within the reduction reactor system by reforming the hydrocarbons with such oxidants as water and oxygen inside the reduction reactor which under steady state conditions contains metallic iron which acts as a reformation catalyst. The amount of carbon in the DRI can be reliably controlled by modifying the relative amounts of water, carbon dioxide and oxygen in the composition of the reducing gas fed to the reduction reactor. The amount of carbon in the DRI is controlled by the amount of water in the reducing gas fed to the reduction reactor while the addition of oxygen provides the energy necessary for such DRI carburization.

Abstract: A method and apparatus for producing DRI, prereduced materials, or the like, utilized in the steelmaking industry, where hydrogen contained in the gas stream purged from the reduction reactor is separated (preferably by means of a PSA system) and recycled to said reduction reactor. The productivity of the reduction plant is increased by using the separated hydrogen as a chemical reductant in the reactor, instead of using it as fuel. This is particularly useful in upgrading existing DRI production plants.

Abstract: A continuous heat treating furnace in which heat is efficiently recovered from the combustion exhaust gas from the heating section of a continuous annealing furnace. The continuous annealing furnace of the metal strip is a heating furnace or a heating device provided with plural burners for heating to a predetermined temperature a steel material or a continuously supplied metal strip by means of combustion of the burners; a regenerative heat exchanger for collecting a sensible heat of a combustion exhaust gas of the burners, reserving the heat in a regenerator and supplying a predetermined gas to the regenerator to recover the heat to the predetermined gas; and a preheating section for blowing the predetermined gas from the regenerative heat exchanger to the metal strip for preheating. The heat exchanger body is divided into at least three sections, each section having a regenerator.

Abstract: Annealing is performed in the annealing chamber (2) of the annealing furnace (1) under a protective gas atmosphere. A partial-stream cleaning device (3) for the protective gas is connected to the annealing chamber. The protective gas can be cooled, the condensate forming from water vapour and rolling oil residues is then separated and/or undesirable gas components are removed by adsorption. Once the cleaning process has been running for so long that the protective gas essentially no longer contains any rolling oil residues, the protective gas may be passed through a hot reaction chamber (4) in which oxygen is removed from it so that the dew point drops and easily oxidised alloying components of the annealing charge are protected against oxidation.

Abstract: A process and installation for preheating scrap containing organic matter, in which flue gas is afterburned in an afterburner combustion chamber at a temperature at more than 1200.degree. C. The after-burned hot flue gases are guided, without being cleaned, via a heat exchanger. Fresh intake air is heated in the heat exchanger by sensible heat of the after-burned hot flue gases. A first portion of the heated intake air at a temperature above an ignition temperature of organic matter is guided in adjustable amounts through at least one basket filled with scrap. Another portion of the heated air exiting the heat exchanger is made available in adjustable quantities to the afterburner as hot blast and/or mixed in the another portion of heated intake air with the after-burned hot flue gases.

Abstract: The invention relates to a boiler construction successive to a smelting furnace, particularly a flash smelting furnace, whereby a direct flow from the radiation section of a waste heat boiler to the convection section thereof is prevented by means of an intermediate plate located in the boiler, advantageously made of cooler pipes and arranged in a direction essentially parallel to the flow. At the same time, the return of the gas flow to the outlet opening of the smelting furnace is prevented in order to reduce the tendency to dust accretions caused by the gases. By means of a flow pattern thus optimized, the eddy currents or dead areas in the radiation section are remarkably reduced, which lengthens the delay time advantageous mainly for heat transfer.

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 method and apparatus for preheating a reactor feed, comprised of an iron ore (10) and a process gas (21), in an iron carbide process for making steel is provided. The apparatus comprises a process gas preheater (40) having a furnace (56) and a heat exchanger (58). The process gas (21) is heated uniformly in tubes (117) of furnace (56) by burners (100). Excess heat generated by furnace (56) is captured by heat exchanger (58) and used to preheat combustion air (61) and ore (10).

Abstract: The invention relates to a waste heat boiler construction provided in succession to a suspension smelting furnace, particularly a flash smelting furnace, in which construction the dust-bearing gases created in the suspension smelting furnace are prevented from directly flowing from the radiation section of the waste heat boiler into the convection section thereof, in order to reduce the tendency to dust build-ups caused by these gases, and in order to advantageously utilize the total volume of the waste heat boiler and to extend the residence time simultaneously. The invention also relates to a method for intensifying the mixing of gases and for extending the total residence time in the radiation section of the waste heat boiler.

Abstract: There is disclosed a copper smelting process. At first, blister copper is produced in a blister copper-producing facility. Then, the blister copper is caused to flow through blister copper launders into one of anode furnaces, and refined into copper of higher quality in the anode furnace. In the refining operation at the anode furnace, the receiving step and the oxidizing step are carried out at least partly in an overlapping fashion.

Abstract: A method and apparatus for cooling the exhaust gases from a molten phase furnace, such as a smelting furnace. The exhaust gases are conveyed from the furnace to a vertically extending cooling shaft disposed above the furnace, where the exhaust gases are indirectly cooled by means of a cooling gas in a circulating system. From the cooling shaft, the exhaust gases are conveyed to a waste heat boiler, where heat is recovered from the exhaust gases as saturated or superheated, pressurized steam.

Abstract: In a process integration, particularly with a blast furnace, nitrogen under pressure is moisturized by the addition to it of hot, pressurized water. The moisturized nitrogen is expanded and power thereby generated. The nitrogen is not mixed with combustion gases. Improved heat balance and work recovery are achieved.

Abstract: In a process integration, particularly with a blast furnace, low grade fuel gas produced by the furnace is compressed and moisturized. The moisturized fuel is burnt using a major part of a compressed air stream to support its combustion. The resulting combustion gases are then expanded with the generation of power. The minor part of the air is separated into oxygen and nitrogen. Oxygen is used in the blast furnace.

Abstract: Air is taken from the air compressor of a gas turbine including in addition to the compressor a combustion chamber and an expansion turbine. The gas turbine drives an alternator. The air taken from the compressor is cooled in heat exchanger to remove heat of compression therefrom. The air is separated in an air separation plant into oxygen and nitrogen. A stream of oxygen is withdrawn from the plant and used in a blast furnace in which iron is made. The off-gas from the blast furnace is a low grade gaseous fuel. It is compressed in compressor which has interstage cooling to remove at least some of the heat of compression. The compressed fuel gas is passed through the heat exchanger countercurrently to the air stream. The resulting pre-heated fuel gas flows into the combustion chamber of the gas turbine and is burned therein to generate gaseous combustion products that are expanded in the turbine. A nitrogen stream is withdrawn in the air separation plant.

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 process for the gaseous reduction of iron ore to sponge in a vertical shaft, moving bed reactor wherein a hot gaseous mixture of hydrogen and carbon monoxide generated by the internal steam reformation of gaseous hydrocarbon(s), preferably methane or natural gas, is used to reduce the ore without the need for any external catalytic reformer. A reducing gas recycle loop is established to which hydrocarbon and reclaimed waste hot water are fed in the proper proportions as the reducing gas make-up source with the sponge iron produced in the reduction reactor being used to catalyze hydrocarbon reformation, and with the carbon content of the recycled gas being maintained low by removing carbon dioxide therefrom.

Abstract: Energy for melting iron oxide or wustite is supplied by pre-heated natural gas which is combusted with oxygen in gaseous form and the oxygen contained in the preheated feed materials. Such combustion produces carbon monoxide and hydrogen gas, thus the combustion products are carbonizing to molten iron. The carbon monoxide and hydrogen evolved at the surface of the molten metal is post-combusted above the bath to form a mixture of carbon monoxide, carbon dioxide, hydrogen, steam and nitrogen. The heat generated by this post-combustion is sufficient to supply the energy for all chemical reaction requirements as well as to melt the wustite charge or smelt the preheated iron oxide charge.

Abstract: Process and apparatus for the rapid efficient melting of solid ferrous metal scrap without direct exposure to water vapor, carbon dioxide, oxygen or oxygen-containing gases, using natural gas and/or other caloric gaseous fuels. The apparatus includes a furnace having a refractory base, means for introducing ferrous metal such as solid steel scrap to the wall area, means for providing a slag layer over the solid steel scrap, and gas burner means for emitting one or more forced gas flames for superheating the slag layer to a liquid which covers the scrap and for agitating and circulating the molten slag to form a highly-efficient heat-transfer medium for melting and refining the steel scrap while it is insulated against contact with gases, particularly water vapor, carbon dioxide, oxygen or oxygen-containing gases. The process may operate continuously and can recover heat for scrap preheating, turbine power and other efficient uses.

Abstract: The present invention relates to an apparatus for preparing binder-free hot briquettes for smelting purposes consisting of iron-containing pyrophorous finely divided solids. Before briquetting, the finely divided solids are blown-through by means of a rising oxidating heated gas flow and held in a fluidized bed. The gas flow is controlled in such a way that by oxidation of at least part of the metallic iron the temperature of the finely divided solids is increased to about 450.degree. to 65020 C. Subsequently, the solids are briquetted in hot condition. Characteristic for the invention is that there is added to the fluidized bed sensible heat from the outside until oxidation of part of the metallic iron starts, and that the fluidized bed is submitted to the effect of vibrations favoring the the conveying of the solids over the fluidized bed.

Abstract: The invention relates to a method and apparatus for reducing dust accretions while treating exhaust gases containing sulphur dioxide in smelting furnaces. According to the invention, on the roof (10) of a waste heat boiler connected to a smelting furnace (16), there is placed a nozzle (11), wherethrough some oxygen-bearing gas is conducted into the radiation chamber (13) of the waste heat boiler, which gas brings about a change in the composition of the exhaust gases and simultaneously reduces the accumulation of dust accretions.

Abstract: This invention relates to a method and apparatus for reducing iron oxide to metallic iron, utilizing a continuous process employing a reducing gas with high hydrogen and carbon monoxide content made by a catalytically reforming mixture of hydrocarbons, reacted off-gases from the reduction process and steam generated from waste heat from the process and or flue gases. Carbon dioxide and water vapor present in the reacted off-gas is utilized as a hydrocarbon reforming oxidant. Steam generated from waste heat from process and/or waste flue gas is also used as a hydrocarbon reforming oxidant. The steam injected into the process gas stream is also used to control the hydrogen-carbon monoxide ratio required for efficient reduction of iron oxide to metallic iron.

Abstract: To gain electric energy in addition to producing molten pig iron, from lumpy iron ore and solid fuels, by using a direct reduction zone for the reduction of the iron ore to sponge iron and a meltdown-gasifying zone for the production of molten pig iron, carbon carriers are used in, and oxygen-containing gases are supplied to, the meltdown-gasifying zone. The reduction gas forming is fed into the direct reduction zone. The reduction gas reacted there is supplied as top gas to a power generation plant including a turbine. In order to adapt the power generation to the power consumption by simultaneously avoiding any influence on the metallurgical conditions at the production of pig iron and its further processing, the charge of carbon carriers into the meltdown-gasifying zone is varied as a function of the gas consumption of the power generation plant in a manner that, with a higher gas consumption, the volatile constituents of the charge are increased and the C.sub.

Abstract: An improved method and apparatus for recovery of waste heat of the type having a first heat exchanger which transfers heat to a working fluid and a second heat exchanger which transfers heat from the working fluid is disclosed. The improvement comprises the provision of at least one storage tank for the working fluid having a volume calculated by the flow rate of the working fluid multiplied by a time difference between the time in which the combusiton chamber has its peak fuel requirement and a next subsequent time at which a maximum amount of waste heat is available to the combustion chamber. This minimum capacity can be obtained by the provision of one tank or several tanks having a combined storage capacity which meets or exceeds the calculated volume. Preferably the storage tank, or combination of storage tanks, is positioned between the heat exchangers so as to receive heated working fluid from the first heat exchanger and provide heated working fluid to the second heat exchanger.

Abstract: The installation comprises mainly a reactor (1) for the gasification of powdered coal on a bath (2) of liquid iron, a cooling flue (9) constituting a boiler connecting the outlet of the reactor (1) to a vapor superheater (11) fed with vapor (26) issuing from the boiler, a dust-removing cyclone (13) connected to the outlet of the superheater (11), a thermal exchanger (14) connected to the outlet of the cyclone (13) in which a drying fluid (31, 32)is heated by thermal exchange with the combustible gas, a conditioning tower (16) connected to the outlet of the thermal exchanger, the conditioning tower being connected to a dry electrofilter (17) which feeds a storage gasometer (20) through a three-way valve (21). The heated drying fluid (32) and the vapor (28,30) issuing from the superheater (11) are employed in the installation for preparing and conveying the fuel and the comburent fed to the reactor.

Abstract: An arrangement for preheating scrap includes a scrap treating furnace into which at least one exhaust gas duct from a metallurgical furnace enters. In order to attain a higher efficiency in preheating, the scrap treating furnace has a through chamber for a plurality of adjacently arranged or superposed scrap receiving vessels. Each of these vessels is provided with its own gas inlet opening and with its own gas exit opening. The scrap treating furnace also includes a charging means on one end of the through chamber to receive at least one scrap receiving vessel and a discharging means on the other end of the through chamber to receive at least one scrap receiving vessel. A conveying means for moving the scrap receiving vessels in cycles from the charging means to the discharging means as well as gas conducting means for connecting the gas exit openings with the gas inlet openings of neighboring scrap receiving vessels are arranged within the through chamber.

Abstract: This invention relates to ladle heating methods and apparatus. More particularly, this invention pertains to rapid high temperature ladle preheating utilizing an optimized heating cycle by involving oxygen and combustion air preheated by recuperation in the fuel burning process. Controlled oxygen flow directed into the process is used to increase the heat input during the initial preheating phase and to insure maximum efficiency of the system during the soaking phase of ladle preheating. The disclosed ladle preheating station comprises a refractory lined lid including a partially open refractory ring for docking a portion of a ladle rim having a significant protrusion caused by a local accumulation of solidified metal or slag, said refractory lid opening shaped to receive said protrusion within the opening while providing a gap between said metal deposition and the refractory lid.

Abstract: A furnace for melting metals, in which the heating of the metal to be molten takes place at least partly by conducting hot gases along this metal. Means are provided for recycling the hot gases through the furnace chamber. The gases are either combustion gases of a burner disposed in the furnace chamber, or an inert gas heated outside the furnace chamber.

Abstract: The invention pertains to a process and a device for the melting and holding in the molten state light metal alloy loads. There are provided two chambers respectively referred to as the loading-melting chamber and the holding-tapping chamber, interconnected by a channel with reduced section. The loading-melting chamber is placed at a level which is above that of the other chamber and a space under the loading-melting chamber houses a heat exchanger for heating the combustion air by combustion products.

Abstract: A heat recovery and storage system for use in connection with a melting furnace. In such system, heat from the exhaust gas of a melting furnace is recovered and used to preheat scrap metal and to maintain such preheated scrap metal in its preheated form until it is charged into the melting furnace.

Abstract: A process and apparatus for heating a steel bath charged with scrap which efficiently utilizes converter waste gas to supplement external energy sources is presented.

Abstract: The present invention relates to a method and an apparatus for the recovery and recycling of heat from hot exhaust gases, specifically from exhaust gases in metallurgical processes and from warm gases having an exiting temperature of below about 800.degree. C. According to the preferred embodiment of the present invention, warm or hot exhaust fuel gases transfer their retained heat to the lower portions of vertically positioned, capillary-type action heat transfer pipes. Cold air is then directed past the upper portion of the heat pipes, thereby transferring the heat of the heat transfer pipes to the cold air. The now heated air gains further heat, prior to introduction into the blast furnace, by passing over, previously heated refractory gratings.

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

Abstract: Apparatus for gasification of carbon (C) in the form of carbon, hydrocarbons and/or hydrocarbon compounds, comprising a reactor (1) into which injection of carbon, oxygen gas and iron oxides takes place, beneath the surface of an iron melt, and in which carbon is injected in stoichiometric excess in relation to the amount of oxygen in the form of oxidic compounds contained in the melt, the reactor having a total inner pressure exceeding atmospheric pressure.According to the invention an exhaust gas pipe (6) from a reactor (1) makes a gas-tight connection with a cooler (8), which together with the reactor (1) forms a sealed unit; and a regulating valve (13) for adjusting and maintaining an overpressure in said unit is provided and placed on the cool side (12) of the cooler (8).

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

Abstract: The invention relates to an apparatus for converting matte in two parallelly connected converters (I, II) with essentially equal blowing rates, corresponding the full capacity of the sulphuric acid plant receiving the process gases. Instead of an arrangement where the following converting periods of the two converters (I, II) are carried out in turns, the converting periods of the converters are now partially overlapping in such a fashion that their blowing periods are staggered, so that blowing is always performed in the first converter while the second converter is being charged or poured. By using this method it is possible to achieve very short waiting periods between the converting periods, additional heating is unnecessary and the pair of converters renders a continuous and even gas flow, which has a higher sulphur dioxide content than normally.

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

Abstract: The lid of a ladle heater includes a valve gate rod opening so that the ladle can move toward and away from engagement with the rim of the ladle about a valve gate rod. Cylindrical plug elements are supported between the lid of the ladle heater and the ladle and move apart to straddle the stopper rod, and as the lid moves toward engagement with the rim of the ladle the cylindrical plugs engage the ladle rim as the lid continues its movement, thus resulting in the cylindrical plugs moving into and closing the stopper rod opening.

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

Abstract: A cupola system for production of gray iron employs otherwise wasted heat to preheat fuel, pig iron, flux and compressed air fed into a melting furnace, by diversion of melting furnace exhaust-gases through a preheating furnace containing feeding conduits for the fuel, pig iron and flux, and for the compressed air; the preheating furnace is laterally inclined downwardly from a point of exhaust to a chimney, to the melting furnace; the diverting means includes a closed, downwardly concave reflecting top over the melting furnace, and the preheating furnace has a concave roof; an important provision of the invention is employment of a maximum number of conventional size and shape tuyeres in a radial array in the melting furnace.

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

Abstract: An apparatus is provided for regulating the percentage quantities of individual gases present in the combustion air supplied for reaction processes in metallurgy. A molecular sieve absorption material is used on the intake air to absorb the inert constituents to thereby enhance the quantity of oxygen present. The apparatus utilizes several molecular sieve materials in a continuous manner such that one of the devices containing the molecular sieve material is being purged for regeneration while another device is absorbing the inert constituents, while yet another device is cooling, i.e., getting ready for the absorption operation. The countercurrent flow of heated intake air, which air is derived from the metallurgical reaction process, is used in the apparatus for regenerating the molecular sieve material.