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: An electric furnace (containing an immersed electrode) and a process for the recovery of lead, arising especially from solid residues. Fines, which are a product of physically crushing spent batteries, are melted under not very reducing conditions in the presence of a small amount of carbon. This melting allows separating the crude lead and the lead-rich slag so as to remove sulphur in the form of sulphur dioxide and to optionally recover the crude lead. The lead-rich slag is then reduced with a suitable amount of carbon so as to separate the lead-free slag and the crude lead, which again can recovered.

Abstract: Dust like substances which are recovered from a garbage or refuse incinerator are destroyed, eliminated or disposed of by smelting in a low shaft electric furnace having at least one electrode heating a slag melt therein. The dust is introduced into the melt by a lance opening beneath the melting surface and gas produced by the smelting process is subjected to cleaning. The slag may be continuously or discontinuously withdrawn and slag formers may be compensatorily added. A metal bath consisting predominantly of iron may be provided below the slag melt to protect metallic components of the dust upon the smelting thereof.

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: In order to regulate the combustion air flow rate of a flue gas collection device (1) of a metallurgical reactor (2) comprising a combustion chamber (4) supplied with air by a variable flow fan (9), a set value C.sub.0 for the oxygen content in the flue gases in the discharge duct (5) is set, the oxygen content M.sub.1 of the flue gases at the outlet of the combustion chamber (4) is measured, using C.sub.0 and M.sub.1, a setting C.sub.1 for varying the combustion air flow rate is calculated, a variable representative of the sudden variations of the flow rate of unburnt gases at the outlet of the metallurgical reactor (2) is measured and a setting C.sub.2 for the combustion air flow rate is calculated to achieve complete combustion of the unburnt gases in the flue gases; the values C.sub.1 and C.sub.2 are added to obtain a setting for the combustion air flow rate which is sent to the regulation device of the fan (9); these calculations may be carried out by electronic means (14, 15, 16).

Abstract: During melting in an electric melting furnace of iron products such as pig iron, scrap iron, directly reduced iron pellets, and various alloy metals, or mixtures of the foregoing having greatly varying impurities, solid carbon dioxide is led over the melting hearth shortly before, during, and after charging. Explosive burning of the combustible constituents is thus prevented in that the oxygen is displaced during the charging operation by the expanding gaseous carbon dioxide produced. The method makes possible electric steel production with reduced accumulation of dust and fumes in that formation thereof is largely eliminated directly at the source. By cutting down on the high volumes of gas and gas temperatures occurring during charging without carbon dioxide, substantially smaller filter installations are needed, whereby the amount of savings on investment and operating costs economically compensates for the cost of the carbon dioxide utilization.

Abstract: An incinerator for the disposal of biohazardous waste has a sealed enclosure defining a combustion chamber with upper, first level intermediate, second level intermediate and lower portions. The upper chamber portion is an inclined chute with a door into which a plurality of cylindrical metal containers of waste are loaded. The bottom run of the chute has a stepped, centrally expanding dimension so different sized containers will be self-centered. A pair of laterally-spaced drums is disposed in the first level intermediate portion, at a constriction which stops further descent down the chute of the leading container. Banks of first level TIG torches are arranged to arc to the drums, providing heat for "cooking" waste in the unopened containers in the upper portion with rising gases and for opening the leading container and incandescently acting on solid materials spilled therefrom.

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: A unit for the metallurgical treatment of molten steel, located in steel teeming ladles, by heating and vacuum treatment. The ladle-metallurgical treatment unit serves for the mutual treatment of steel meltings by heating and vacuum treatment. It consists of two treatment stations, each of which is provided with a stationary tank 1, 2 for incorporating the steel teeming ladle 3, 4, and each is provided with a laterally movable vacuum lid mechanism 13. A heating device with a swiveling heating lid 9, which is arranged centrally between the two treatment stations, is brought into the working position over one of the two steel teeming ladles 3, 4.

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: An incinerator for the disposal of biohazardous waste has a sealed enclosure defining a combustion chamber with upper, first level intermediate, second level intermediate and lower portions. The upper chamber portion is an inclined chute with a door into which a plurality of cylindrical metal containers of waste are loaded. The bottom run of the chute has a stepped, centrally expanding dimension so different sized containers will be self-centered. A pair of laterally-spaced drums is disposed in the first level intermediate portion, at a constriction which stops further descent down the chute of the leading container. Banks of first level TIG torches are arranged to arc to the drums, providing heat for "cooking" waste in the unopened containers in the upper portion with rising gases and for opening the leading container and incandescently acting on solid materials spilled therefrom.

Abstract: Smelting apparatus for use in making elemental silicon and alloys thereof is disclosed. The apparatus includes an electrometallurgical furnace having a body which includes a reactor external to the body which includes carbonaceous reductant.

Abstract: A plant for the processing of exhaust gases of an electric melting furnace for steel is disclosed, which allows to improve the cleaning of heavy-metal-containing exhaust gases from electric arc furnaces for steel production from scrap, which allows to decrease the energy use for capturing waste from the exhaust gases, which avoids the odor molestation by the waste gases generated in connection with an electric melt furnace operation during the preheating and for making useful the exhaust gases for the smelting under incorporation of the drying of oil-containing roll sinter muds, where simultaneously the oil-content of these roll sinter muds is used for saving of electric arc melting energy.

Abstract: A process for treating hazardous particulate generated during a manufacturing process is provided. The process includes the steps of: passing particulate material through at least one duct toward a waste collection device; feeding an additive into the duct to be mixed with the particulate material, upstream from the waste collection device; and passing the particulate material mixed with the additive into the waste collection device. A scrap remelting apparatus is also provided.

Abstract: A smelting process for making elemental silicon and alloys thereof is disclosed. The smelting process is of the electrometallurgical type for producing elemental silicon from silicon dioxide including silicon alloyed and silicon in a substantially pure form. The process includes establishing and maintaining countercurrent contact between collected oxide and a bed of carbonaceous reductant for reducing at least part of the collected oxide to additional elemental silicon.

Abstract: The specification discloses a ladle furnace apparatus for refining molten steel tapped from a steelmaking furnace therein. There are introduced molten steel and a slag making material into the ladle. The outer and inner lids of the ladle furnace are put on the respective receiving surfaces of the ladle to close the opening thereof. In the interior of the ladle, the slag making material is slagged by arc heating thereby to refine molten steel introduced therein by means of the slag. During the refining process, the suction of gas is carried out from a space formed between the outer lid and the inner lid. Therefore, a dust containing gas generated by reaction of the molten steel and slag enters the space between the outer lid and the inner lid passing through a gap formed between the inner lid and the ladle or electrode holes disposed in the inner lid to be sucked therefrom.

Abstract: Toxic compounds, entrained in water, are dissociated in an electric arc (e.g. 12000.degree. F.) in an airtight chamber charged with oxygen; metal ions (M.sup.+) resulting from dissociation are recombined as gaseous oxides (MO.sub.x) which are educted from the chamber and disposed of.

Abstract: The invention relates to an electrothermal process of separation and refining of metals from recovery materials containing a distillable metal, characterized by the fact that it consists:on the one hand, in a melting stage where the process materials are placed in an electric furnace, in order to vaporize said distillable metal in view of extracting in vacuum the vapor of the distillable metal and subjecting it to oxidization at the same time, and of pouring into ingots the liquid metals remaining in the furnace pot, and,on the other hand, and not dependent on the melting stage, in a distillation stage of the distillable metal oxide thus collected, and a condensation of the resulting metal vapor in order to recover said distillable metal in a liquid form and to pour it into ingots.Applications: to the recovery of iron, nickel and cadmium contained in electric storage batteries.

Abstract: The invention relates to a method and arrangement for producing liquid iron in an electric melter or furnace. The method and arrangement relate to producing liquid iron in the electric melter, utilizing highly reduced sponge iron, which is defined as sponge iron resulting from reduction of iron bearing material, and having a degree of metallization being in excess of 60%. (Metallization is expressed as analyzed metallic iron divided by analyzed total iron). The method and arrangement relate to transferring the highly reduced sponge iron, together with at least some residual carbon, to a melter in a hot state and substantially in the absence of oxygen. This avoids heat loss and reoxidation. The highly reduced sponge iron and residual carbon are then passed in a controlled manner, into the melter, where one or more electrodes operate in a low resistance mode.

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: A method for preventing deposits or build-ups of dust in off-gas channels for dust-containing off-gases from electrothermal smelting furnaces. This is done by blowing an additional gas tangentially into the furnace off-gas channels at the positions where build-ups or deposits of dust normally occurs. Hence a gas spiral is provided between the inner wall of the furnace off-gas channels and the dust-containing, hot furnace off-gas. Recirculated and cooled furnace off-gas is preferably used as additional gas. For open furnaces where the furnace off-gas is completely combusted before it enters into the furnace off-gas channels, air can be used as additional gas. The temperature of the additional gas is preferably kept below the sintering temperature of the dust in the furnace off-gas.

Abstract: An electric arc furnace having at least one electrode and a burner and first and second supply systems for respectively supplying an oxygen containing gas and fuel to the burner. An exhaust gas conduit is connected to the furnace and includes a first damper for controlling the flow rate of exhaust gases and a second damper for controlling the flow of dilution air into the exhaust conduit. First and second position sensors are coupled to the first and second dampers, respectively, for sensing the positions thereof, a temperature sensor is coupled to the exhaust conduit for sensing the temperature therein and a pressure sensor is coupled to the furnace for sensing the furnace pressure. A first control is coupled to the first supply system and to the temperature sensor and to the first position sensor for initiating and controlling the flow of oxygen containing gas in relation to the temperature in the conduit and the position of the first damper.

Abstract: A suction duct having two opposed suction ports is disposed at the top wall of a shroud for a steel making arc furnace such that the two suction ports are in opposed relationship with respect to each other across an opening formed through the top wall of the shroud for permitting the lateral movement of a scrap bucket suspension device. An injection pipe or pipes are horizontally disposed in the suction port such that the injection pipes disposed in one of the suction ports are staggered vertically with respect to those disposed in the other suction port. A fluid is horizontally sprayed from a nozzle or nozzles of the injection pipes across the opening so that vertically spaced fluid shelves are formed across the opening.

Abstract: An upwardly open vessel which, in use, contains a metallurgical melt, the upwardly open vessel having an upper rim. A suction hood having a lower rim sized and shaped so that, in use, the lower rim of the suction hood opposes the upper rim of the upwardly open vessel but is spaced therefrom to permit ambient air to enter through an annular gap therebetween. A covering bell having a lower rim is mounted on the underside of the suction hood in position so that, in use, the lower rim of the covering bell isolates a portion of a slag cover on a metallurgical melt in the upwardly open vessel. Corresponding openings are provided in the suction hood and the covering bell to permit access to the isolated portion of the slag cover by an externally operated probe or the like.

Abstract: A method of preheating scrap metal with impure gases discharging from a metallurgical vessel includes the steps of conducting a first portion of the gases to a container of scrap metal, contacting the scrap metal with the gases for preheating the same whereby additional impurities are generated, withdrawing the impure gases after contact with the scrap metal and mixing the same with a second portion of impure gases from the metallurgical vessel, thermally cracking the mixture in a combustion chamber to remove impurities and thereafter removing particular matter from the gases prior to the discharge to the atmosphere.

Abstract: The present invention is directed to apparatus and a process for separating large from small particles suspended in a moving stream of gas by centrifugal forces which in a preferred embodiment includes sifting of large particles in a stream of gas to strip small particles away from the larger particles. The apparatus and process is especially adapted for separating dry finely divided particulate materials having small particles from about 0.05 micron to about 45 microns from larger particles suspended in the moving gas stream.

Abstract: An arc furnace installation wherein the arc furnace is air-tightly enclosed with a shroud and a scrap preheating chamber moves into or out of the shroud in such a way that the preheating chamber may be selectively brought to a position immediately above the arc furnace, a scrap preheating position spaced apart from the arc furnace by a predetermined distance and a scrap charging position outside of the shroud. The number of openings of the shroud may be reduced to a minimum and consequently the total area of the openings may be minimized.

Abstract: A fumes control system for use with a furnace having a top-chargeable furnace vessel mounted on a first support with means for charging the furnace adjacent to the vessel and means for collecting the melt from the furnace adapted to overlie a second support defining a tapping site adjacent to the furnace vessel. The fumes control system comprises a housing covering the top and sides of the furnace in sealing engagement with the first and second supports and is adapted to entirely enclose the furnace and collecting means. The fumes control system further comprises exhaust means with dampers associated therewith, which dampers are interconnected via control means to selectively exhaust fumes generated during charging, melting/refining and tapping operations at the respective sites.

Abstract: Arc furnace has a furnace shell, a furnace lid with lid ring and a lid lifting and swivelling means as well as a lid opening in the furnace lid for exhausting the flue gas from the interior of the furnace and a flue gas exhaust nozzle for removing the flue gases above the lid opening, the nozzle being supported on the furnace lid ring. By means of this design feature as well as a guide arrangement and a locking means the flue gas exhaust nozzle can be completely integrated into the operating steps of the arc furnace in a simple and economical fashion.

Abstract: A method is provided for maintaining a predetermined effluent gas pressure within an electric arc melting furnace of the type having an off-gas duct system. The method involves establishing, by simulation, correlations between specific measurable physical characteristics within the furnace and in the off-gas duct system and then utilizing these correlations to establish a program for automatically varying the volume of off-gas flow through the duct to maintain effluent gas pressure within a desired range within the furnace. Sensors are provided in the duct system to monitor the physical characteristics in the off-gas flow and for transmitting data to a microprocessor adapted to operate flow-regulating apparatus in the duct system to thereby maintain the pressure within the furnace within a predetermined range.

Abstract: A method and a hood for mixing a hot furnace gas with a second gas before the furnace gas is discharged from a furnace by directing the hot furnace gases out via a hood which forms an uninterrupted space for gas with the furnace is disclosed in which the second gas is fed along the side walls of the hood substantially countercurrently in relation to the hot gases emerging from the furnace in order to mix the gases with each other into a toroidal vortex, and that the gases are removed from this vortex tangentially.

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: A primary duct is provided for supplying hot waste gas from an electric furnace to a preheater bucket charged with scrap. A preheating waste gas duct connected to the bucket is branched into a discharge duct for releasing preheating waste gas from the apparatus and a recycling duct for recycling preheating waste gas to the primary duct. In the vicinity of the junction of the primary duct and the recycling duct, an air inlet is formed for supplying air into the primary duct for burning the preheating waste gas.

Abstract: A melt reduction furnace has a flat gas-tight roof through which the oxide feeding electrode projects an extent less than usual inside the furnace to reduce its breakage risk, and a side wall gas exhaust opening above an upstanding threshold providing low-velocity gas exhaust while the threshold holds back gas flow with possible dust below the opening.

Abstract: An enclosure for a metallurgical vessel has a front access door to permit movement of charging devices into the enclosure for charging the metallurgical vessel disposed therein. A gas collector is mounted in the upper end of the enclosure, a first hood mounted in the enclosure for movement between an operative position above the vessel and an inoperative position remote from the vessel. When in its operative position, the hood is disposed in coupling engagement with one side of the gas collector. A second hood is fixedly coupled to the other side of the gas collector. Dampers are disposed between each hood and the gas collector.

Abstract: A sound and dust insulating wall separates the furnace hall from the casting hall in a metallurgical mill. In order to allow the transport of an overhead crane from one hall to the other, an upper wall portion of the separating wall pivots out of the way. The wall portion comprises frame elements and a plurality of relatively thin overlapping slats. The wall portion is opened by pivoting the frame elements about a horizontally extending hinge. The slats, secured to the frame elements by hinges, also pivot, so that the slats only block the now opened crane passageway by not more than the width of one individual slat.

Abstract: To save space in furnace installations and obtain an optimum continuous charging, an arrangement is disclosed in which electric smelting furnaces are arranged in a furnace bay unilaterally, close to the adjacent ladle bay and the associated charging equipment and bins are provided sequentially in a vertical zone between the crane runways of the two bays. Bins are filled with iron material, such as iron sponge, alloying mechanisms, and fluxing substances by a conveyor traveling thereabove. The contents of bins are delivered through conveying and metering devices which are provided between crane runways to a reversible conveyor extending at a lower level and equipped with discharge mechanisms and fed through a charging tube 1 into electric furnace. A traveling metering device is provided for adding alloying into the furnace, and fluxing material for subsequent treatment in the ladle, through charging tube. A housing encloses the furnace on all sides, to prevent emissions.

Abstract: Particulate lime is discharged from a nozzle into an electric arc furnace through an inlet port in the roof or top of the furnace. The inlet port is laterally displaced from the electrode ports in the center of the top of the furnace. Lime is supplied to the nozzle through a duct pivoted on the furnace to swing the nozzle into alignment with the inlet port for charging lime into the pot and into a retracted position where the nozzle is shielded by the top from heat produced in the furnace. The nozzle has an axial length, axial direction, and cross sectional shape and width constructed and arranged to direct the lime away from the side wall and toward the central portion of the furnace without any significant impingement of the lime directly on the electrodes.

Abstract: An explosion venting device for metallurgical furnace enclosures consists of a plurality of panels adapted for restrictive movement relative to the roof and sidewalls of the enclosure and cover openings therein. The panels absorb the shock blast of an explosion occurring within the housing by lifting outwardly from the housing walls. Being restrictively movably mounted, the blast force may be vented in any desired direction. When the explosive force ceases, the panels will return to their rest position against the housing.