Abstract: Finely powdered oxidde ore is introduced (at 17) in a reactor (11), possibly together with slag-formers, and treated in three zones in the reactor. The material is preheated and possibly melted in an upper, oxidizing zone by the combustion of carbon monoxide and hydrogen gas from the middle zone below with a gas containing oxygen. In a middle zone consisting of a slag bath, the preheated and possibly melted oxide material at least partially reduced by the simultaneous injection of carbonaceous material and/or material containing hydrocarbon (15, 16) and thermal energy supplied primarily by means of gas heated in a plasma generator (14). Finally, the material is caused to sink into a lower zone at the bottom of the reactor, from where it is tapped intermittently, together with the slag, through a tapping aperture (19).

Abstract: Calcium carbide is prepared from a powdered lime material. The powdered lime material, possibly together with a reducing agent, is injected with the aid of a carrier gas into a plasma gas generated by a plasma generator. The heated lime material, together with any reducing agent used and the energy-rich plasma gas, is then introduced into a reaction chamber substantially surrounded on all sides by a solid reducing agent in piece form. When the lime material consists of quicklime, this is melted and reduced to liquid carbide and when the lime material consists of powdered limestone, it is burnt directly in the reaction zone to form liquid carbide.

Abstract: Recovery of oxide or silicate-bound metals from liquid slag, in metallic or sulphidic form is carried out by reduction with carbonaceous reducing agent, the thermal energy required to maintain the temperature and perform the reduction and sulphidization being provided by blowing gas preheated in a plasma generator below the surface of the slag bath. The vapor of volatile metals is condensed in known manner in a condensor, the non-volatile metals and sulphides formed being collected in the form of molten drops which are allowed to settle out of the slag.

Abstract: Recovery of zinc from a gas containing zinc vapor is carried out by means of lead circulating in a circuit and separating out pure metallic zinc by cooling said lead. The gas containing zinc vapor is brought into intimate contact with atomized lead in liquid form which takes up the zinc. The lead is introduced at the top of a cooling tower (1) and the gas is conducted in counter-flow to the atomized lead droplets. Lead collected at the bottom of the tower (1) is transported (7) to a separating chamber (8) where it is cooled, so that the zinc is segregated from the lead and can be separated (10). The lead is then cooled further before being recirculated (15, 16) to the top of the cooling tower.

Abstract: Ferrosilicon is manufactured from a material containing silica and a raw material containing iron by injecting these materials, possibly together with a reducing agent, with the help of a carrier gas into a plasma gas. The silica and the iron raw material, possibly with the reducing agent, heated in this way are then introduced with the energy-rich plasma gas into a reaction chamber surrounded by a solid reducing agent in lump form, the silica thus being brought to the molten state, being reduced and reacting with the iron to form ferrosilicon.

Abstract: A gas mixture obtained from reduction of material containing zinc oxide in a furnace, is cleaned from accompanying vapor of metals or compounds having a boiling point higher than zinc and from accompanying dust particles by cooling the hot gas mixture to almost the saturation temperature of zinc vapor by the introduction therein of solid or liquid metal.

Abstract: In a method of manufacturing aluminium-silicon alloy from natural mineral containing alumina and silica and carbon powder, the natural mineral in powder form is injected together with a reducing agent in the form of a carbon carrier, with the aid of a carrier gas into a plasma gas produced in a plasma generator. The mineral thus heated is then introduced, together with the reducing agent and the energy-rich plasma gas, into a reaction chamber surrounded substantially on all sides by solid reducing agent in lump form. Examples of the natural mineral include andalusite, cyanite, silimite, nepheline, quartz, clay containing alumina, such as bauxite, and mixtures of two or more of these minerals.

Abstract: Pure ferro-alloy metals are isolated from fine-grained crude oxidic mineral products by reduction melting and subsequent anodic liberation of the iron. The reduction melting is performed in a plasma-heated furnace into which the fine-grained oxide material is blown together with carbon powder and circulating exhaust gas, extremely over-heated in a plasma generator, the quantity of carbon powder being dosed so that most of the alloy metal(s) is converted to carbides during the reduction. After electrolysis, the anode residue will consist primarily of alloy metal carbides from which the metal can be recovered by known methods.