Abstract: In order to lower the sulfuric content of the offgas from a smelter reactor in which iron oxide is reduced to molten iron, in the presence of sulfur contaminants, a sufficient amount of a source of zinc is included in the charge to the reactor that the combined weight of the zinc source and the iron oxide source contains at least about 0.6% Zn (calculated as elemental zinc), on a dry weight basis. The temperature of the offgas is maintained at or above approximately 700.degree. C. Vaporized zinc, present in the offgas, binds with sulfur in the offgas to precipitate solid ZnS. After removal of the ZnS, the offgas may have a sulfuric content below 50 ppm by volume of H.sub.2 S equivalent. Suitable sources of zinc include blast furnace dust, electric arc dust, basic oxygen furnace dust, zinc calcine, and zinc sinter.

Abstract: The present invention provides a method for producing direct reduced iron in a continuous and efficient fashion, which includes providing a mixture of a particulate iron oxide composition and a particulate carbonaceous reductant composition; the mixture being substantially unagglomerated and having a moisture content of less than about 14% water by weight; positioning the mixture onto a rotary hearth furnace; subjecting the mixture to reducing conditions to reduce a substantial portion of the iron oxide, thereby producing sponge iron; and discharging the sponge iron from the rotary hearth furnace.

Abstract: A melting furnace for reforming steel-making slag so as to be available, for example, to roadbed ballast by mixing steel-making dust with the slag in molten states, which is provided with a fuel oxygen burner for melting the slag and the dust, a slag charging port for charging the slag in molten state into the furnace, a dust feeder for supplying the dust into the furnace, a slag feeder for supplying the slag in powdered state into the furnace, a storage portion for storing a molten mixture of the slag and the dust in a quantity corresponding to a tilting angle of the furnace body and an outlet port for discharging the molten mixture, and is possible to dispose the slag efficiently whether the slag is in the powdered or molten state.

Abstract: The present invention is concerned with a process for extracting and recovering lead or lead derivatives in high purity from various materials containing lead sulphate, and particularly copper smelter flue dusts. The present process also allows the substantially complete recovery or recycling of precious metals otherwise lost in flue dusts wastes.

Abstract: The beneficiation of an electric arc furnace (EAF) dust waste stream comprising zinc compounds by collecting and combining dust from two or more EAF batches with coal fines to form briquettes, adding the briquettes to a final EAF batch with the charge, and collecting the dust from the final EAF batch, so that the zinc in the beneficiated dust is of a greater proportion than in a typical batch of EAF dust. Alternatively, the EAF dust can be split into two dust streams, one of which is returned to the EAF, while the other is treated in a hydrometallurgical process. Either waste stream preliminary can be treated by adding carbon and an ammonium chloride solution, separating any undissolved components from the solution, displacing undesired metal ions from the solution using zinc metal, treating the solution to remove therefrom zinc compounds, and further treating the zinc compounds and the undissolved components resulting in zinc products and an optional iron-carbon feedback.

Abstract: Heavy metals substantially free from heavy metal chloride contaminants are recovered from electric arc furnace (EAF) dust by bringing the dust into contact with a carbonaceous reductant utilizing a plasma arc of a DC sealed atmosphere plasma arc furnace so as to volatilize (vaporize) the hazardous heavy metals therein, and then bringing the vaporized heavy metals into contact with an alkali metal gettering agent to thereby form alkali metal chlorides and thereby substantially inhibit the formation of heavy metal chlorides in the off-gas.

Abstract: In a method for processing solid residues from refuse incineration plants the slag is melted and heavy metals from the melt (16) are separated for reutilization. The slag is directly transferred from the refuse incineration plant into a first heating chamber (2) and melted there under oxidizing conditions. The melt (16) produced therefrom is transferred to a second heating chamber (3), in which the heavy metal compounds are reduced to their metallic form. Furthermore, additional finely divided residues, such as fly ash, boiler ash and filter dust, are introduced into the second heating chamber (3) via a hollow graphite electrode (19). The melt (16) is then passed on to a third heating chamber (4), in which the residual readily volatile metals are vaporized and the residual non-volatile metals are sedimented. The essentially heavy-metal-free melt is then cooled to form vitreous granules.

Abstract: Iron-rich material waste products, such as electric arc furnace dust, are formed with an organic binder into discrete shapes, such as briquettes and/or other solid shapes. The shapes can then be used in iron and steel making processes and the iron and heavy metal values in the waste product recovered.

Abstract: A method for separation and recovery of metals and metal oxides from industrial minerals and waste materials containing zinc, lead, cadmium, arsenic, iron, mercury and selenium. The metals and metal oxides in dust form are mixed with a reducing agent and additives, agglomerated, heated above 800.degree. C., and contacted with a flow of inert, reducing or slightly oxidizing gases to volatilize the metals and metal oxides for recovering separate from solid residual product.

Abstract: A method of agglomerating oil-containing steel mill waste includes the step of combining a first steel mill waste component with a second steel mill waste component to form a mixture. The first waste component includes substantially dry non-oily steel mill waste and the second waste component includes oil-containing steel mill waste. The first waste component and the second waste component are agglomerated.

Abstract: A method for producing a more concentrated iron product from an industrial waste materials stream comprising iron and non-iron constituents such as EAF and basic oxygen furnace dust generally comprising the steps of compacting or briquetting the waste materials stream, roasting the waste materials stream at temperatures above about 980.degree. C. to convert the iron compounds to direct reduced iron, crushing the roasted waste materials stream, separating the iron compounds contained in the waste materials stream by magnetic separation or flotation, and providing the iron compounds back to the EAF or basic oxygen furnace.

Abstract: In a method of processing iron-containing metallurgical residual substances, offgases containing iron-containing particles are washed out in a wet process and separated in the form of sludge. The sludge is then dehydrated and agglomerated; subsequently, the agglomerates are recycled into an iron melt production process. To recover the iron contained in the sludge, the agglomerates are passed exclusively into a refining stage of the steel production process. The present method may be used in a steel production process which produces steel from pig iron, as well as optionally from scrap and/or iron ore and/or sponge iron. The refining stage is performed using an oxygen blowing process.

Abstract: An improved method for the recovery of metal and/or chemical values from an industrial waste stream containing zinc, cadmium, lead and/or iron compounds by heating the waste stream in a reducing atmosphere, treating the resultant fumes in an ammonium chloride solution, separating any undissolved components from the solution, adjusting the pH of the solution, if necessary, to less than about 6.3, displacing undesired metal ions from the solution using zinc metal, treating the solution to remove therefrom zinc compounds, adjusting the pH of the solution to about 6.5 to about 7.0, and further treating the zinc compounds and the undissolved components, as necessary, resulting in the zinc products and the optional iron-carbon feedstock.

Abstract: A method for producing direct reduced iron or/and pig iron from an industrial waste materials stream such as EAF and blast furnace dust generally comprising the steps of separating the materials contained in the waste materials stream by magnetic separation or flotation, briquetting the iron-containing materials separated during the separation process with carbon, and providing the briquettes to a reduction furnace or/and to a small scale blast furnace or cupola furnace to produce direct reduced iron or/and pig iron, respectively. The exhaust streams from the process are further treated to recover chemical values and to allow the recycle of the exhaust streams to the main process.

Abstract: A method for the production of Group IA salts during a process for the recycling of industrial waste streams containing Group IA compounds and iron and/or zinc compounds, by heating the waste stream in a reducing atmosphere, treating the exhaust fumes from the heating step with an ammonium chloride leaching solution resulting in a Group IA salt containing precipitate, and recovering the Group IA salts from the precipitate.

Abstract: In a method of recycling iron and steel industry waste by processing the waste as an object substance by the use of a rotary kiln, the object substance is changed into a valuable material while the object substance travels within the rotary kiln from an upstream side to a downstream side. The object substance is heated on the upstream side of the rotary kiln within a reducing atmosphere to be reduced and molten into a reduced and molten product. The reduced and molten product is quickly sent to the downstream side without being adhered to an internal wall of the rotary kiln. The valuable material is extracted from the reduced and molten product which may be directly discharged out of the rotary kiln or which may be discharged after the reduced and molten product is once kept in a basin formed in the vicinity of the downstream side of the rotary kiln.

Abstract: A method of producing briquettes for use in steelmaking processes in a melting vessel. Prior to the briquetting step, the residues should have added thereto essentially uniformly distributed carbon carriers, the amount of carbon carriers added corresponding precisely to the amount required for causing an essentially complete reduction of the iron-oxide containing residues. The residues obtained as byproducts in a smelting plant can thus be reused to a high degree by adding them to a steelmaking process. A residue briquette can be supplied to the melting vessel in an amount of up to 30%. This permits the use of residues instead of scrap.

Abstract: The use of and methods to use a novel category of hydrocarbon for direct reduction of iron ore. The novel hydrocarbons used as reducing feedstocks would normally be destined to become hazardous wastes or else their products of decomposition would be hazardous wastes. Such hydrocarbons are inclusive of but not limited to organic phosphates, organic sulfates, organic nitrogens, organic mercury or tin, contaminated hydrocarbons, and halogenated hydrocarbons. This category of hydrocarbons is otherwise difficult to utilize, incinerate, or otherwise dispose of safely. Polluting byproducts are almost always released. However a DRI reactor is herin fitted to utilize them productively and safely. These hydrocarbons would be used as an alternative to or admixture with the usual hydrocarbon feedstocks of choice, methane or related short chain hydrocarbons.

Abstract: Methods and apparatus for the hydrometallurgical separation and recovery of biological nutrients, cadmium, lead, and gypsum from raw materials such as electric arc furnace flue dust. Biological nutrients, including zinc and iron, are selectively separated and recovered from raw materials, including metals and metal oxides, and are selectively and variably recombined, to achieve a biological nutrient product which a desired relative concentration of zinc and iron. The process is a closed system generating no solid waste, no liquid water or acid waste streams, and whereby gypsum, and substantially all hazardous wastes such as lead and cadmium, are separated and recovered from raw material for sale as commercial products.

Abstract: A process for treating iron-bearing material with a carbonaceous material to form a dry mixture, wherein the amount of carbonaceous material added exceeds the stoichiometric amount required to reduce the metal oxide to elemental metal. In one embodiment, the process also includes blending an organic binder with the dry mixture. The dry mixture is agglomerated to bond the dry mixture and form green compacts. The green compacts are loaded into a heated furnace and heated for about 5-12 minutes at a temperature of between about 2100.degree.-2500.degree. F. to reduce the iron oxide containing compacts to compacts containing elemental iron and an excess amount of carbonaceous material wherein the excess amount of carbonaceous material counteracts re-oxidation of the elemental iron. The reduced compacts are then discharged from the furnace.

Abstract: A method for the recovery of high purity zinc oxide products, and optionally iron-carbon feedstocks, from industrial waste streams containing zinc oxide and/or iron. The waste streams preliminarily can be treated by adding carbon and an ammonium chloride solution, separating any undissolved components from the solution, displacing undesired metal ions from the solution using zinc metal, treating the solution to remove therefrom zinc compounds, and further treating the zinc compounds and the undissolved components, as necessary, resulting in the zinc products and the optional iron-carbon feedbacks. Once the zinc oxide has been recovered, the purification process is used to further purify the zinc oxide to obtain zinc oxide which is at least 99.8% pure and which hsa predeterminable purity and particle characteristics.

Abstract: A method and apparatus for processing a contaminated free-flowing material and, in particular, filter dust from industrial metallurgical waste and domestic waste incineration plants are disclosed.

Abstract: A process for recovering iron from an iron oxide bearing mass. The process includes forming a bed of lump coke in a vertical shaft furnace, feeding the iron oxide bearing mass and scrap metal onto the bed of lump coke and combusting the coke in the coke bed while injecting a plasma gas having a temperature greater than about 5,000.degree. F. into the coke bed to form a reaction zone within the coke bed having a temperature in excess of 4,000.degree. F. The iron oxide bearing mass and scrap metal fed onto the bed of lump coke is melted to form a molten phase containing molten iron oxide and molten scrap metal. The molten phase flows into the reaction zone and a film is formed on the lump coke within the reaction zone, the iron oxide in the film being reduced by carbon from the coke to form molten iron in a solid/liquid reduction. The molten iron is discharged from the furnace.

Abstract: Electric arc furnace production of recycled steel is plagued by the formation of an iron-depleted, metal-rich electric arc flue dust (EAFD). In the present invention, we recover at least about 85 wt. % of the base metals in the EAFD (i.e., lead, cadmium, copper, and zinc) as high quality metals products without producing any solid, liquid, of gaseous wastes. We use a recyclable calcium chloride/hydrochloric acid leach mill solution to extract the base metals form the EAFD in a reactor under a controlled pH of about 2.6 at an elevated temperature and pressure in an oxygen environment wherein the solids content in the reaction slurry is about 15-30 wt. %. In this way, we place the base metals in solution while leaving the iron as a solid hematite iron complex. When separated from the metal-rich solution, the solid hematite iron complex is recycled to the electric arc furnace. The base metals are precipitated and recovered.

Abstract: A method and system for recovering metal from steel waste products is disclosed. This method and system works on such hazardous and/or toxic wastes as mill scale, flue dust and slag. This method and system operates by mixing the steel waste produce with a flux composition and then melting the mix in a single phase two electrode electric arc furnace. Once the mixture is melted by the heat from the electrodes, the electro-magnetic field induced in the melted mixture serves to enhance the recovery from the steel waste product of useful steel material. Furthermore, this method and system provide a cost effective solution to the hazardous waste disposal problems impacting steel refineries around the world and does so in a manner that removes the toxicity of the waste while producing a variety of useful products, including high grade steel and neutralized fill.

Abstract: A method for the recovery of iron products, specifically direct reduced iron and iron oxide suitable for use as the feedstock for steel mills, from industrial waste streams containing iron, by treating the waste streams with an ammonium chloride leaching solution, separating the undissolved precipitates comprising iron compounds from the leachant solution, and further treating the undissolved precipitants by elevated temperature roasting, resulting in the iron feedstocks.

Abstract: In a process for treating fine ore, the fine ore is dried by aid of a hot drying gas flowing around the ore particles of the fine ore, the drying gas, after having flown around the ore particles, is purified while releasing entrained dust ore particles and the dust ore particles are collected and admixed to the dried fine ore. In order to avoid process disturbances in the further processing of fine ore due to excessive portions of dust ore particles present within the fine ore,drying is effected in the whirl-bed, i.e., fluidized-bed method under simultaneous wind-screening of the fine ore, whereinthe drying gas is passed through the fine ore under formation of a whirl bed andthe speed of the drying gas is fixed at a rate at which entraining of dust ore particles having dimensions below a predetermined dimension is effected, andthat the dust ore particles entrained by the drying gas are separated, collected and admixed to the dried fine ore in dosed amounts.

Abstract: This invention describes a method of reprocessing zinc- and iron oxide-containing residual material. Zinc- and iron oxide-containing dust and/or sludge is granulated with water, granules and carbonaceous material are fed to a circulating fluidized bed system, the gas-solids suspension circulated in the circulating fluidized bed system is fed to a second fluidized bed reactor, the solids discharged from the second fluidized bed reactor are recycled to the reactor of the circulating fluidized bed system, 50 to 75% by volume of the oxygen required to gasify the carbonaceous material are fed as fluidizing gas to the reactor of the circulating fluidized bed system and 25 to 50% by volume of said required oxygen are fed as a fluidizing gas and secondary gas to the second fluidized bed reactor, iron oxide-containing material is discharged from the reactor of the circulating fluidized bed system and zinc-containing material is discharged with the exhaust gas from the circulating fluidized bed system.

Abstract: A method for the removal of calcium byproducts created during the production of an iron-based feedstock suitable for use as the feedstock for steel mills, from industrial waste streams containing iron, by treating the waste stream with an ammonium chloride leaching solution, treating the leachant with a soluble ammonium salt in which the negative ion will form an insoluble compound with calcium, and separating the undissolved precipitates comprising iron compounds and calcium compounds from the leachant solution. The undissolved precipitants may be treated further by elevated temperature roasting, resulting in the iron-based feedstocks.

Abstract: A method for the separation and recovery of metals selected from the group consisting of iron, cadmium, zinc, and lead, from raw material comprising a mixture of metals, which comprises the steps of heating the raw material to a temperature sufficient to substantially vaporize cadmium, zinc, and lead, and insufficient to substantially vaporize iron; separating secondary dust and vapors produced during the first step from the residual sinter mass, which mass comprises iron; slurrying the secondary dust in an aqueous solution of ammonia ammonium carbonate to dissolve zinc and cadmium; separating a zinc/cadmium bearing leach liquor from substantially insoluble lead containing particles by filtration; treating the zinc/cadmium bearing leach liquor to recover cadmium by adding metallic zinc to the leachate to produce a cadmium containing cement; separating the cement from the leach liquor; and removing ammonia from the leach liquor to precipitate basic zinc carbonate.

Abstract: A process for recovering iron from iron-bearing materials including steel mill waste and iron-bearing ores. The process includes the steps of combining the iron-bearing materials, having metal oxides including iron oxides therein, with carbonaceous material to form a dry mixture. The dry mixture is agglomerated under conditions sufficient to mobilize volatile matter from the carbonaceous material to function as a binder and bond the dry mixture and form green compacts. The green compacts are then loaded into a preheated rotary hearth furnace void of compacts to form a layer of compacts no more than about two compacts high. The green compacts are heated for about 5 to 12 minutes at a temperature of between about 2150.degree. F. to 2350.degree. F. to reduce the compacts and evolve undesirable oxides from the compacts. The reduced compacts are then discharged from the rotary hearth furnace whereupon they are soaked to provide additional time for reaction to achieve 99% or more reduction of the iron oxides.

Abstract: A method and an apparatus for the purification of residual products from flue gas purification plants.Between a wet-desulphurization plant (1) for flue gas and an associated waste water-treatment plant (2) for the purification of the water used in the wet-desulphurization there is inserted a leaching apparatus (3, 7, 4) for the purification of hazardous residual products supplied through a conduit (6) from flue gas purification in dry-and and semidry-desulphurization plants by means of waste water supplied through a conduit (5) from the plant (1).

Abstract: A conglomerated material based on metallurgical by-products and characterized in that it contains 2-10% of fibers, 9-25% wt of an alkaline earth metal hydroxide, and % wt of water.

Abstract: A method for the production of an iron-based feedstock suitable for use as the feedstock for steel mills, from industrial waste streams containing iron, by combining an iron poor material such as exhaust fumes from metals production processes with the waste streams, treating the combined waste stream with an ammonium chloride leaching solution, separating the undissolved precipitates comprising iron compounds from the leachant solution, and further treating the undissolved precipitants by elevated temperature roasting, resulting in the iron-based feedstocks.

Abstract: A method of treating steel mill waste containing iron oxides and silica includes reacting the steel mill waste with an alkali aqueous solution in an amount sufficient to raise the pH to at least about 7 to solubilize silica to form soluble silicate compounds and silica gels and thereby produce a chemically reactive mixture. The mixture is reacted with an alkaline silicic compound to produce a solid, stable, non-polluting material.

Abstract: A method for the production of an enriched iron product, specifically direct reduced iron and iron oxide suitable for use as the feedstock for steel mills, from industrial waste streams containing iron, by combining an iron oxide rich material such as mill scale and/or used batteries with the waste streams, treating the combined waste stream with an ammonium chloride leaching solution, separating the undissolved precipitates comprising iron compounds from the leachant solution, and further treating the undissolved precipitants by elevated temperature roasting, resulting in the iron feedstocks.

Abstract: A method making pig iron employs an in-bath direct reduction performed in a metallurgical vessel which has above it a melting cyclone in which iron-oxide-containing material fed thereinto is pre-reduced by hot reducing gas coming from the vessel. Molten material passes downwardly from the melting cyclone into the vessel. In order to recover zinc from a dust containing zinc and/or zinc oxide, the dust is fed into the melting cyclone. Zinc is allowed to vaporize out of the dust into the hot gas in the melting cyclone. The hot gas containing zinc is discharged from the melting cyclone, and zinc-containing material is extracted from this hot gas.

Abstract: A process for recovering iron values from waste iron oxide, especially iron oxide dust from steelmaking furnaces, wherein the iron oxide is mixed with a water-insoluble thermoplastic material and heated to melt the plastic to form a binder for the iron oxide particles, and discrete bodies formed of the mixture are returned to a furnace to recover the iron values. The plastic binder is present in an amount sufficient to serve as a reductant to reduce the iron oxide to metallic iron when the plastic is combusted with oxygen in the furnace. The invention also includes the discrete bodies so formed of iron oxide and thermoplastic binder.

Abstract: The invention relates to a hydrometallurgical process for decontaminating soils 1 which are polluted with metallic elements, comprising a stage of basic leaching I so as to bring about the dissolution of the metallic elements to be removed, a cementation stage II bringing about the precipitation 6 of said elements in metal form, performed by electrochemical exchange with a zinc powder 5 produced by a stage of electrolysis III of the solution 7 originating from the cementation stage. In accordance with the invention a complementary addition of zinc is performed, preferably at the exit of the leaching stage in the form of a leachate 17 of waste from iron and steel manufacture, especially of dust 13 from electrical steel manufacture 15.

Abstract: The foundry dust is fed to a first furnace atmosphere which is preferably at 1000.degree. to 1100.degree. C. With the dust pellet being continuously rolled around, it remains therein until in particular chlorine, alkali and lead compounds have almost completely evaporated out of the dust. Experience has shown this takes an hour. In that operation a scavenging gas flow is fed to the furnace atmosphere whereby the lead-chlorine-alkali vapour produced in the rotary cylindrical furnace is passed out of sane to a condensation and filtering apparatus.Reducing agent, in particular coal, is then introduced into the foundry dust and same is fed to a further furnace atmosphere which in particular is at 1150.degree. to 1350.degree. C., where it is continuously rolled around.

Abstract: A method for recovering zinc from zinc comprising the steps of:producing agglomerates containing carbon from dust which contains zinc in a form of zinc oxides;charging the agglomerates into molten metal, the zinc oxides in the agglomerates being reduced and vaporized into a vaporized zinc; andcollecting the vaporized zinc as zinc oxide with a generated dust.

Abstract: Finely divided ferruginous material is intimately mixed with finely divided carbonaceous material and agglomerated and formed into pellets typically of a few cubic centimeters volume to form a feedstock for a smelting operation. The carbonaceous material includes carbon in both high reactivity and low reactivity forms typically provided respectively by sewage sludge or other biosolids and by coke fines, kish graphite, natural graphite, lignite or brown coal. Smelting is conducted in a bath smelting furnace with the bath temperature of at least 1420.degree. C. and preferably 1500.degree. C. in a manner controlled to destroy any organic compounds present, to use carbon as a source of fuel, to carburise the iron to around 4% carbon or higher and to provide an off-gas which can be processed to collect any volatilized metal values.

Abstract: A process for feeding a second stream of pulverulent materials into a pneumatic conveying line carrying a first controllable flow of pulverulent materials is presented. The second stream of pulverulent materials is fed at a controlled rate and the control of the first flow is rendered insensitive to disturbances caused by the feeding of the second stream by directly or indirectly controlling the first flow upstream of the injection point of the second stream.

Abstract: In a process for producing an iron melt, iron ore is reduced to sponge iron in a direct reduction zone. The sponge iron is melted in a meltdown gasifying zone while supplying carbon-containing material under gasification of the carbon-containing material to reducing gas and under formation of a slag. The reducing gas is injected into the direct reduction zone, is reacted there and is drawn off as a top gas. The reducing gas and/or the top gas is subjected to gas scrubbing and the sludges separated during scrubbing are admixed with binder and coal dust and subsequently are agglomerated.

Abstract: A process for smelting iron-containing source material in a reactor containing a slag bath, includes generating heating and reducing conditions in at least one reducing region of the bath by injection of fuel/reductant and oxygen-containing gas by at least one top submerged lance. The source material is fed to the reactor together with additional reductant and with flux at or adjacent the at least one reducing region so as to be subjected to smelting reduction, using coal as the additional reductant. The rates of injection of oxygen and fuel/reductant are controlled to achieve required and sufficient reducing conditions by providing the injected gas with an oxygen content from about 40% to about 100% sufficient for a degree of combustion of the fuel/reductant of from about 40% to about 50%. The CO and H.sub.

Abstract: The present invention relates to a process for the production of metal alloys, metal oxides and slag-based products, such as mineral wool, from industrial waste materials. More specifically, the present invention relates to a process for recycling industrial waste materials into valuable commercial products, including, pure metals, metal alloys, metal oxides, and a molten slag comprising non-reducible metal oxides which thereafter can be converted to vitreous fiber and shot. Industrial waste materials suitable for use in the present invention include metal-containing waste products, particularly inorganic hazardous waste materials. The present process accomplishes total recycling in such a manner that the entire industrial waste material is consumed and converted to useful products.

Abstract: The present invention relates to a process of recycling filter dust obtained during the production of steel in an electric arc furnace. Filter dust is injected and mixed with the smalls of carbon containing material in the slag or at the interface between the slag and the molten metal bath in the melting tank. The process of the invention also improves the degree of efficiency of the foaming of the slag while increasing the profitability of steel production.

Abstract: Residual metallurgical materials which contain zinc and lead are reprocessed by a thermal treatment in a circulating fluidized bed. The required heat is generated in that solid carbon is combusted in the fluidized bed reactor of the circulating fluidized bed. A solid carbon content of 5 to 30% is maintained in the lower part of the fluidized bed. Oxygen-containing gases are supplied to the upper part of the fluidized bed reactor, and CO.sub.2 is formed only in such an amount that zinc metal will not be reoxidized. Substantially all solids are removed from the discharged suspension in a recycle cyclone and are recycled. The gas is cooled to a temperature at which zinc metal is oxidized to ZnO. The dustlike compounds of zinc and lead are separated from the gas.

Abstract: The present invention provides a method for processing environmentally undesirable materials including petroleum coke and the sulfur and heavy metals contained therein and agglomerated waste dust from an electric arc furnace and the zinc, cadmium, lead and iron oxides contained therein and of providing fuel and a charging material for a process of making molten iron or steel preproducts and reduction gas in a melter gasifier. Metallized arc furnace waste dust material from a reduction furnace is introduced into the melter gasifier. The petroleum coke, oxygen and metallized waste dust material are reacted to produce reduction gas and molten iron from the iron oxides in the waste dust material. The molten iron contains the metals freed from combustion of the petroleum coke. The reduction gas is removed from the melter gasifier for use in the reduction furnace to produce an top off gas containing vapors of zinc, cadmium and lead.

Abstract: In a method of producing molten pig iron from lumpy, iron-ore-containing charging substances, the latter are reduced in a reduction shaft furnace by means of a reducing gas, wherein the iron sponge particles obtained are melted in a melter gasifier under supply of coal and oxygen-containing gas under simultaneous formation of the reducing gas, and the reducing gas is returned to the reduction zone of the shaft furnace.To enable charging of larger amounts of fine ore and/or ore particles, such as oxidic iron fine dust incurred in a metallurgical plant, in addition to the charging substances, the fine ore and/or the ore dust is supplied with solid carbon carriers to at least one dust burner working into the melter gasifier and is reacted in a substoichiometric cumbustion reaction.