Abstract: The invention relates to a method to be used in producing easily volatile metals from their sulfides. The method employs two closely connected furnaces, a reduction furnace and a converter, which are operated at normal pressure, so that the material transfer therebetween is arranged to be carried out continuously at normal pressure through the channels provided in between the furnaces. As a result of chemical reactions taking place in the furnaces, the hydrostatic pressure in the furnaces changes, and the circulations caused by these changes through the channels at the same time bring about recycling of the sulfide matte needed in the process from the reduction furnace to the converter and the recycling of the molten metal from the converter to the reduction furnace.

Abstract: The invention relates to a method for feeding a reaction gas, such as oxygen or oxygen-enriched air to a flash smelting furnace through a concentrate burner, so that the gas is fed in around a pulverous material distribution channel located in the middle of the burner. Oxygen or oxygen-enriched air is fed into the reaction shaft through tubular channels in several separate gas jets, and the discharge velocity of the gas jets is adjusted.

Abstract: The invention relates to a method for utilizing zinciferous waste from metal smelters, such as steel smelters, so that the transmission of fluorides to the highly zinciferous secondary dusts is prevented during the treatment of the gas obtained from the waste smelting furnace. Fluorides are extremely harmful for the zinc process, and therefore it is important to prevent them from entering the process. By adjusting, according to the invention, the temperature and composition of the exhaust gases created in the smelting treatment of zinciferous dusts and other waste, the fluorides and the highly zinciferous fraction are obtained in different end products. Other valuable metals are recovered from the metal layer created on the bottom of the furnace.

Abstract: The invention relates to a method for producing zinc, cadmium, lead and other easily volatile metals from sulfidic raw materials in a pyrometallurgical process. In the method, zinc sulfide concentrate is fed into molten copper in atmospheric conditions, at a temperature of 1,450.degree.-1,800.degree. C., so that the zinc, lead and cadmium are volatilized, and the iron and copper remain in the molten metal or in the metal sulfide matte created in the furnace.

Abstract: The invention relates to a method for feeding a reaction gas, such as oxygen or oxygen-enriched air to a flash smelting furnace through a concentrate burner, so that the gas is fed in around a pulverous material distribution channel located in the middle of the burner. Oxygen or oxygen-enriched air is fed into the reaction shaft through tubular channels in several separate gas jets, and the discharge velocity of the gas jets is adjusted.

Abstract: The present invention relates to a method for concentrating a certain mineral fraction attached to air bubbles from a slurry to the foam layer accumulated on the surface, so that the concentration takes place in three different mixing zones. The apparatus of the invention is formed of a colon-like flotation arrangement and of flow guides, a flow attenuator and an agitator belonging thereto. The flotation reactions are created in the bottom zone, wherefrom air bubbles and mineral particles carried by them are directed in a controlled fashion onto the surface of the apparatus. The flotation apparatus is so designed, that a strong agitation in the bottom zone can be used without causing harmful separation of the foam in the bottom part of the apparatus.

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: The invention relates to a method and apparatus for raising the temperature and mixing efficiency of mainly non-combustible pulverous solid particles so high, that a desired smelting and volatilizing is achieved. The method is characterized in that the heating and mixing are carried out in at least two stages. Advantageously the reactions are made to happen in a suspension smelting furnace, such as a flash smelting furnace.

Abstract: The invention relates to an appparatus where the wet scrubbing of several different gas flows is carried out in at least three scrubbing towers, and the droplet separation of scurbbed gases takes place in a cyclonic, uniform droplet separator constructed of several cylinders, so that the obtained product is a pure and droplet-free gas.