Abstract: A method for concentrating dilute sulfuric acid involves feeding dilute sulfuric acid through at least two electrolytic cells depolarized by sulfur dioxide, and through a cation conductive membrane separating the cathode and anode sides in the electrolytic cell. Also provided is an apparatus for concentrating sulfuric acid, wherein at least a first electrolytic cell is in fluid communication with a second electrolytic cell, and wherein a cation conductive membrane separates the cathode and anode sides in the electrolytic cells.

Abstract: The invention relates to a method for producing gaseous hydrogen and strong sulphuric acid (97-100 wt-%) simultaneously from sulphur dioxide gas and water. Sulphur dioxide gas stream is divided into two separate sub-streams, the first sub-stream is routed for water decomposition in a partial thermochemical cycle of the hydrogen and sulphuric acid production and the second sub-stream is fed to the oxidation of the sulphur dioxide to sulphur trioxide.

Abstract: A method for coating a construction material made of metal alloy with a functional metal. The functional metal is deposited electrolytically on the surface of the construction material selectively so that the deposition occurs on the grain boundaries of the construction material and other points of discontinuity. The invention also relates to a construction material product, which is selectively coated with a functional metal.

Abstract: The invention relates to a method for producing gaseous hydrogen and strong sulphuric acid (97-100 wt-%) simultaneously from sulphur dioxide gas and water. Sulphur dioxide gas stream is divided into two separate sub-streams, the first sub-stream is routed for water decomposition in a partial thermochemical cycle of the hydrogen and sulphuric acid production and the second sub-stream is fed to the oxidation of the sulphur dioxide to sulphur trioxide.

Abstract: The method and furnace according to the invention enable a continuous processing of anode slime and are particularly suited to be connected to a process where anode slime is treated by hydrometallurgic methods after roasting. In the method according to the invention, the slime containing valuable metals and selenium is dried, roasted, sulfatized and cooled. The method includes steps to be carried out in succession, in continuous operation, so that the slime forms a slime layer on the conveyor and is conveyed to be treated in successive drying, roasting, sulfatizing and sulfuric acid removal and cooling units.

Abstract: The invention relates to a method for producing magnetically active shape memory metal alloy, said metal alloy containing nickel, manganese and gallium. In the method, the different components of the metal alloy are melted, and the melt is homogenized essentially at the melting temperature; the obtained metal alloy is cast, and the cast metal alloy is subjected to directional solidification at 10-100° C. below the liquidus temperature of said metal alloy.

Abstract: The invention relates to a method for the removal of mercury from gas containing sulphur dioxide and oxygen and from the sulphuric acid vapour contained in the gas. According to the method, the gas is washed with a water solution that contains selenium ions, whereby metallic selenium is formed in the presence of oxygen, which precipitates the mercury in the gas and vapour either as a selenide or in a chlorine-containing environment, as a dichloride of mercury and selenium. Gas washing occurs at a low temperature, below 50° C.

Abstract: The invention relates to a method for treating a fibrous web downstream of slitting. In the method, the finishing of a fibrous web for providing desired properties is performed by using one or more finishing units, at least one of which comprises a web processing apparatus provided with a metal belt.

Abstract: This invention relates to a method for removing mercury from dilute sulphuric acid. According to the method sulphuric acid solution is scrubbed with an aqueous solution containing thiosulphate, which precipitates the mercury present in the sulphuric acid solution either as mercury sulphide or, in a chlorine-containing environment, as a mercury sulphide-mercury chloride double salt. The quantity of thiosulphate to be fed is adjusted so that it precipitates the mercury in the sulphuric acid solution, but still does not form elemental sulphur.

Abstract: The present invention relates to a method for manufacturing an electrically conductive pattern by printing a layer comprising metal oxide on a carrier substrate (2) and reducing the metal oxide to metal. The reduced layer is transferred to an application substrate (7). The present invention also relates to the use of the method.

Abstract: The method and furnace according to the invention enable a continuous processing of anode slime and are particularly suited to be connected to a process where anode slime is treated by hydrometallurgic methods after roasting. In the method according to the invention, the slime containing valuable metals and selenium is dried, roasted, sulfatized and cooled. The method includes steps to be carried out in succession, in continuous operation, so that the slime forms a slime layer on the conveyor and is conveyed to be treated in successive drying, roasting, sulfatizing and sulfuric acid removal and cooling units.

Abstract: The invention relates to a method for producing magnetically active shape memory metal alloy, said metal alloy containing nickel, manganese and gallium. In the method, the different components of the metal alloy are melted, and the melt is homogenized essentially at the melting temperature; the obtained metal alloy is cast, and the cast metal alloy is subjected to directional solidification at 10-100° C. below the liquidus temperature of said metal alloy.

Abstract: This invention relates to a method for removing mercury from dilute sulphuric acid. According to the method sulphuric acid solution is scrubbed with an aqueous solution containing thiosulphate, which precipitates the mercury present in the sulphuric acid solution either as mercury sulphide or, in a chlorine-containing environment, as a mercury sulphide-mercury chloride double salt. The quantity of thiosulphate to be fed is adjusted so that it precipitates the mercury in the sulphuric acid solution, but still does not form elemental sulphur.

Abstract: The present invention relates to method, which helps to reduce and remove the build-up forming on the grate of a fluidized-bed furnace in the roasting of fine-grained material such as concentrate. The concentrate is fed into the roaster from the wall of the furnace, and oxygen-containing gas is fed via gas nozzles under the grate in the bottom of the furnace in order to fluidize the concentrate and oxidize it during fluidization. Below the concentrate feed point, or feed grate, the oxygen content of the gas to be fed is raised compared with the oxygen content of the gas fed elsewhere.

Abstract: The present invention relates to a method for manufacturing an electrically conductive pattern by printing a layer comprising metal oxide on a carrier substrate (2) and reducing the metal oxide to metal. The reduced layer is transferred to an application substrate (7). The present invention also relates to the use of the method.

Abstract: This invention relates to a method for stabilizing a fluidized bed used in roasting by adjusting the oxygen content of the roasting gas in the bed. The fine-grained material for roasting is fed into the furnace above the fluidized bed and the roasting gas, which causes the fluidizing, is fed into the bottom of the furnace through a grate. In this method, the total amount of oxygen in the roasting gas to be fed and the average total oxygen requirement of the material to be roasted are calculated and the ratio between them regulated so that the oxygen coefficient in the bed is over 1.

Abstract: A method for making a joint between copper or copper alloys and austenitic steel alloys, in which method in between the junction surfaces of the objects to be joined together, there is arranged at least one intermediate layer, so that the junction surfaces, including their intermediate layers, are pressed together, and at least the junction area is heated in order to create a diffusion joint. In the method, there is brought a first intermediate layer (3) on the junction surface of the steel object (2) or against said surface, in order to activate the creation of the diffusion joint.

Abstract: The invention relates to a method for the removal of mercury from gas containing sulphur dioxide and oxygen and from the sulphuric acid vapour contained in the gas. According to the method, the gas is washed with a water solution that contains selenium ions, whereby metallic selenium is formed in the presence of oxygen, which precipitates the mercury in the gas and vapour either as a selenide or in a chlorine-containing environment, as a dichloride of mercury and selenium. Gas washing occurs at a low temperature, below 50° C.

Abstract: The present invention relates to method, which helps to reduce and remove the build-up forming on the grate of a fluidized-bed furnace in the roasting of fine-grained material such as concentrate. The concentrate is fed into the roaster from the wall of the furnace, and oxygen-containing gas is fed via gas nozzles under the grate in the bottom of the furnace in order to fluidize the concentrate and oxidize it during fluidization. Below the concentrate feed point, or feed grate, the oxygen content of the gas to be fed is raised compared with the oxygen content of the gas fed elsewhere.

Abstract: This invention relates to a method for stabilizing a fluidized bed used in roasting by adjusting the oxygen content of the roasting gas in the bed. The fine-grained material for roasting is fed into the furnace above the fluidized bed and the roasting gas, which causes the fluidizing, is fed into the bottom of the furnace through a grate. In this method, the total amount of oxygen in the roasting gas to be fed and the average total oxygen requirement of the material to be roasted are calculated and the ratio between them regulated so that the oxygen coefficient in the bed is over 1.