Abstract: In a method for supplying thermal energy by means of a plasma arc heater to a reactor filled with solid, lump reduction material, the thermal energy is supplied via an outer or transferred arc, one electrode of which is formed by the heater and the other electrode of which is formed by the reduction material in the reactor.

Abstract: The invention relates to a method and plant for converting waste material containing and/or comprising thermally disintegratable chemical substances to stable final products such as CO.sub.2, H.sub.2 O and HCl, the waste material being subjected to a plasma gas of high temperature generated in a plasma generator in order to effect disintegration.The waste material in feedable form is caused to flow through a reaction zone, heated by a plasma gas to at least 2000.degree. C. The reaction zone comprises a cavity burned in a gas-permeable filling in piece form arranged in a reaction chamber, by means of the plasma jet from the plasma generator directed towards and projecting into said filling. An appropriate oxygen potential is maintained in at least the reaction zone such that the disintegration products are continuously converted to stable final products.

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: A method and a device is provided for continuously supplying from above piece-shaped, i.e. lumps of, material to a shaft through which a high-temperature gas is conducted from below upwardly to a centrally disposed upper gas outlet. The piece-shaped material at the upper end is fed into the shaft at the top via evenly distributed and closed feed tubes or via an annular feed gap adjacent the periphery of the shaft.

Abstract: A method of reducing and recovering volatile metal from metal oxides comprising the steps of injecting metal oxide-containing material into a shaft reactor, simultaneously injecting reducing agent into said reactor, continuously maintaining said reactor substantially filled with coke, supplying thermal energy to the reactor, preferably by means of a plasma burner, such that at least some of the metal oxides are reduced to metal and melted or volatilized depending upon whether the metal is volatile. The melted metal is removed from the bottom of the reactor while the volatilized metal is permitted to flow upwardly through the shaft reactor in the form of metal vapor together with a gas flow. The coke in the shaft reactor through which the volatilized metal passes is maintained at a temperature in excess of 1000.degree. C., thus screening the upper portion of the shaft reactor and the reactor top by means of the coke so as to prevent condensation of the volatilized metal.

Abstract: The present invention relates to selective reduction of heavy metals out of finely grained, substantially oxidic material by blowing the oxidic material into a furnace together with an amount of reducing agent required for obtaining desired selectivity while simultaneously heat energy is supplied by a gas heated in a plasma generator, the temperature being adjusted to such a level as to correspond to the oxygen potential at which the desired metals are transformed into a particular, isolatable phase as metal melt, metal vapor, speiss or matte and at which the remaining metals enter into a slag phase and can be isolated as slag melt.

Abstract: In a process for manufacturing a gas substantially containing carbon monoxide and hydrogen gas from a starting material containing carbon and/or hydrocarbon, the starting material is injected in powder or liquid form together with an oxidizing agent and slag former in a combustion zone while heat energy is simultaneously supplied. The combustion zone is formed in the lower portion of a shaft filled with particulate, solid, carbonaceous material and sulphur-binding slag former.

Abstract: Silicon is manufactured from powdered material containing silica by injecting this, optionally together with a reducing agent, into a gas plasma with the help of a carrier gas. Thereafter the silica material thus heated, together with the reducing agent if any and the energy-rich plasma gas, is introduced in a reaction chamber surrounded by solid reducing agent in lump form, so that the silica is caused to melt and is reduced to liquid silicon.

Abstract: Disclosed are a method and apparatus for manufacturing sponge iron by the continuous reduction of iron oxides in a shaft utilizing recirculation gases. Reaction gas is removed from the shaft furnace, substantially cleaned of all CO.sub.2 and H.sub.2 O, and then divided into at least two flow portions one of which is passed to a gas generator comprising a gas generating shaft substantially filled with a solid reducing agent and a plasma burner arranged in the lower portion of said shaft. An oxidant is injected into the hot gas from the plasma burner so as to form a gas mixture comprised primarily of CO and H.sub.2, which gas mixture is then mixed with the other flow portion of the cleaned reaction gas in such proportion that the temperature of the resulting reduction gas is suitable for the reduction of iron oxides in the shaft furnace.

Abstract: Disclosed are a method and apparatus for manufacturing sponge iron by the continuous reduction of iron oxides in a shaft utilizing recirculation gases. Reaction gas is removed from the shaft furnace, substantially cleaned of all CO.sub.2 and H.sub.2 O, and then divided into at least two flow portions one of which is passed to a gas generator comprising a plasma burner. A reducing agent such as pit coal is injected together with an oxidant into the hot gas from the plasma burner so as to form a gas mixture comprised primarily of CO and H.sub.2, which gas mixture is then mixed with the other flow portion of the cleaned reaction gas in such proportion that the temperature of the resulting reduction gas is suitable for the reduction of iron oxides in the shaft furnace.

Abstract: A method of manufacturing stainless steel comprising the steps of injecting a starting material containing chromium oxide and iron oxide into the lower portion of a reactor, said reactor containing a solid reducing agent, passing said starting material into a reduction zone within said lower portion, said reduction zone being maintained by the use of a plasma generator adjacent thereto, substantially instantaneously reducing and melting said starting material in said reduction zone, and removing the melted and reduced chromiferous product from the bottom of the reactor. The chromiferous product may then be further refined in an AOD convertor or the like.

Abstract: A method of recovering non-volatile metals from materials in dust form containing metal oxides, comprising the steps of blowing the material into the lower portion of a reactor, said reactor containing a solid reducing agent, passing said starting material into a reduction zone within said lower portion, said reduction zone being maintained by the use of a plasma generator adjacent thereto, substantially instantaneously reducing and melting said starting material in sad reduction zone, and removing the melted and reduced metal product from the bottom of the reactor.