Abstract: The invention relates to a process for the separation and recovery of non-ferrous metals from zinc-bearing residues, in particular from residues produced by the zinc manufacturing industry. The process allows for the valorisation of metal values in a Zn-, Fe- and Pb-bearing residue, and comprises the steps of: subjecting the residue to a direct reduction step, thereby producing a metallic Fe-bearing phase and Zn- and Pb-bearing first fumes; extracting the Zn- and Pb-bearing first fumes and valorising Zn and Pb; subjecting the metallic Fe-bearing phase to an oxidising smelting step, thereby producing an Fe-bearing slag and second metals-bearing fumes; extracting the second metals-bearing fumes and valorising at least part of their metallic content. The main advantage of this process is that an environmentally acceptable output for Fe is obtained.

Abstract: The present invention relates to a method and apparatus for separating undesired toxic metals, such as Zn, Pb and Cd, from iron-containing materials by: sintering a mixture of such materials (typically including EAF dust and mill scale) with carbonaceous particles to form sturdy sinter lumps; preheating such lumps in a non-reducing atmosphere, if needed, to achieve an elevated temperature generally above the vaporization temperature of the undesired metals, but below the sticking temperature of iron-containing lumps (which is typically below the vaporization temperatures of such undesired metals in their oxide form), feeding the lumps at such elevated temperature into a reduction reactor; flowing hot reducing gas through lumps to volatilize undesired reduced metals and carry the volatilized metals out of reduction reactor leaving the iron-containing lumps largely stripped of the undesired metals and ready for discharge and safe and/or useful disposal or re-use, and finally cooling the off gas from the reactor

Abstract: A method of treating dust exhausted from a melting furnace in melting an iron-contained material, comprising the steps of: melting the iron-contained material, with air inside the melting furnace shut out from outside air and collecting the dust from the melting furnace into which a gas exhausted from the melting furnace and containing the dust is introduced; performing a lead-collecting process of collecting water, chloride, fluorine, and lead by heating the exhausted dust in vacuum; and performing a zinc-collecting process of collecting metallic zinc contained in the dust by heating a residue of the exhausted dust in vacuum.

Abstract: A process for treatment of zinc sulfide or other zinc bearing feed materials in conjunction with an iron sulfide containing mineral or compound to effect a separation of zinc from iron by fuming on either zinc and sulphur vapor or zinc sulphide vapor. The vapor is stripped and transported by a carrier gas from the mineral or a molten matte formed from the mineral. The process is operated at a temperature in the region of 1250.degree. to 1400.degree. C. and at a partial pressure of oxygen in the region of 10-.sup.7 to 10-.sup.11 bar. The process is conducted in the presence of a liquid matte phase which contains at least iron sulphide and which is intimately mixed in a bath with a slag phase.

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: The present invention relates to a method for recovering valuable metals contained in various metallurgic waste precipitates and dusts, and also to a method for forming of the rest of the waste precipitate or dust a slightly soluble product suited for further processing. The recovery of valuable metals and the forming of slightly soluble products is carried out in a suspension smelting furnace, in which case the smelting of the precipitates and dusts is mainly reducing.

Abstract: Disclosed is a process of removing zinc from a phosphating process sludge wherein the phosphating process sludge is mixed with an additive adapted to form slaglike compounds of iron, calcium and/or barium with the phosphorus component of the phosphating process sludges. The mixture is reacted at temperatures of at least 800.degree. C. under reducing conditions. A previous agglomeration, particularly pelletizing, of the mixture will be of advantage. For a formation of iron compounds it will be particularly desirable to employ reaction temperatures of at least 900.degree. C., preferably of at least 1000.degree. C. and most preferably of at least 1100.degree. C. Metallurgical dusts are particularly suitable additives. For a formation of iron compounds it will be desirable to select a Fe:P molar ratio of at least 1.0 in case of a reaction temperature of .ltoreq.950.degree. C., of at least 1.5 in case of a reaction temperature of 950.degree. to 1050.degree. C., and of at least 2.