Abstract: The invention relates to a method for recovering the valuable metal content of a mix of contaminated copper raw materials, of which materials at least one is sulphide bearing, and which contain one or more impurities forming the group arsenic, antimony, bismuth, mercury, tin, chlorine and other halogens. The invention is characterized by adjusting the halogen content of the mix so that it is substantially at least stoichiometric in relation to remaining impurities in the group, whereafter the mix is charged to a furnace in which melting can take place and in which the mix is heated to at least 500.degree. C., but beneath the melting points of respective ingredients of the mix, while maintaining good contact with hot gas therewith to expel substantially all of the aforementioned impurities present.

Abstract: Method for producing alkali metal selenite and alkali metal selenate from metallic selenium through selenous acid. The selenium is dissolved in nitric acid to form silenous acid, which is reacted with an alkali metal base to from alkali metal selenite. The formed selenite is then spray dried. Alternatively, the formed selenite is oxidized at elevated temperature in a basic environment at pH 10-12, with hydrogen peroxide as the oxidant, to form selenate, which is then spray dried. The invention also relates to products produced by the method. The products are intended to be incorporated in animal fodder or foodstuffs (solenite), or in fertilizers (selenate), to be thus administered to human beings and animals as trace substances.

Abstract: The invention relates to a method for indicating the presence of concealed minerals and/or deposits in prospecting or exploration operations. A flow of ascending free geogas is analyzed with respect to its content of entrained substances of exploration interest. The gas is suitably sampled at locations beneath or above the surface of the ground, and its content of carried substances caused to be released, and then collected and analyzed. The gas may suitably be caused to flow through a device in which solid substances of interest are collected for example by absorbtion and/or adsorbtion techniques. Electrically charged particles can also be collected with the aid of an electric field.

Abstract: A method of recovering copper and nickel from sulphidic minerals containing copper, nickel and iron comprises the steps of roasting the mineral, preferably to provide magnetite; sulphating, for example with sulphuric acid, sulphur trioxide, metal sulphate and/or sulphur dioxide together with oxygen; and a subsequent leaching of the sulphated material and recovery of copper from the leaching solution, for example by electrolysis. All or part of the leaching solution with its nickel content is recycled to the roasting stage, and the nickel content is removed in the form of nickel oxide together with the leaching residue, from which nickel can be recovered.

Abstract: The invention relates to a method for producing metallic lead from lead-containing starting materials by an oxidizing smelting process and subsequent reduction of the resultant oxidic molten bath. The reduction is effected with solid carbonaceous reduction agent present in the melt, and it is ensured that solid carbonate-containing material, preferably limestone, dolomite or soda ash, is also present in the melt, together with the reduction agent.The method can be applied for working-up lead-starting materials of sulphidic, oxidic or sulphatic kind. In addition, the method can be applied to advantage for working-up lead-carbonate containing starting materials, where at least a part of the carbonate-containing material may comprise lead-starting material.

Abstract: The present invention relates to a method in the excavation of rock caverns, substantially cylindrical vertical caverns, for storing liquids or dry products, or for use in storing process units, in which method an upper and a lower circumferentially extending cavern (4, 11) is formed, the caverns (4, 11) having an outer diameter which is greater than the diameter of the ultimate rock cavern (1); in which the caverns (4, 11) are connected together by means of vertical holes (12) drilled in the region immediately outside the ultimate rock cavern (1), these vertical holes (12) serving to drain water from the aforementioned region, for the purpose of minimizing the extent to which water can penetrate the rock cavern (1). (FIG. 1).

Abstract: The invention relates to a method for recovering lead and lead-alloying elements from battery-type lead waste products, and fractions thereof, such as battery mud, and similar oxidic-sulphatic materials.In accordance with the method, the waste products, together with a solid reduction agent, are introduced to a furnace in which the contents thereof can be vigorously agitated. The amount of solid reduction agent charged is selected so as to ensure the chemical reduction of substantially all the non-metallic lead contained by the waste products, and the alloying elements present therein. The material charged to the furnace is heated to a temperature of between about 1050.degree. C. and 1250.degree. C., while vigorously agitating the furnace contents, so as to melt, split-off and chemically reduce the waste products, to form a lead melt containing the aforementioned alloying elements.

Abstract: The invention relates to a method for recovering the metal values from materials containing at least one of zinc and tin, by smelting the starting materials under oxidizing conditions and reducing the resultant molten bath. The starting materials are first smelted in a furnace while adding flux, to form a slag which is sluggish at selected reduction temperatures and has a low lead contents. The reduction process is carried out while charging solid carbonaceous reduction agent and optionally also sulphur- and/or chlorine-donor material to the slag. The reduction agent and optionally supplied donor material is brought into suspension with the slag, and this suspension is sustained at least during the latter phase of the reduction period, at which the lead content of the slag has fallen to beneath about 1-2%, during which phase the reduction of zinc and tin takes place.

Abstract: The invention relates to a method for purifying aqueous solutions containing at least one impurity element from the group consisting of arsenic, phosphorus, mercury and other heavy metals and solid matter by precipitation in at least two stages with the aid of precipitation reagents possessing ions capable of forming not-readily dissolved hydroxide precipitate. In accordance with the invention the main part of the precipitation reagent is introduced to the stage or stages following the first stage. The impurity element-containing precipitate formed in the aqueous solution subsequent to adding the reagent is separated therefrom substantially completely, and is returned so as to be present in the first precipitation stage, while that part of the solution which has been freed from precipitate in a later stage is withdrawn from the system. Substantially all the impurity element amount present in the ingoing aqueous solution are separated therefrom in the form of a sludge prior to the second precipitation stage.

Abstract: The invention relates to a method for recovering useable products from waste products deriving from the manufacture of aluminium fluoride on the basis of aluminium hydroxide and fluosilicic acid. Mother liquors and washing water from a scrubber in said process, which solutions contain aluminium, silica, fluorine, and phosphorous is reacted in a first step with sodium ions at pH 2-3, and a temperature of 50.degree.-100.degree. C. to give a precipitate of sodium fluoroaluminate, which is isolated. The filtrate from said first step can be reacted with the silica waste product obtained in the above mentioned aluminium fluoride manufacture.

Abstract: The present invention relates to a method for producing a polyaluminium hydroxide complex of a chloride and sulphate type in solid form, an aqueous solution of the polyaluminium hydroxide complex being admixed with at least one water-miscible organic solvent having 1-4 C, the weight ratio of the aqueous solution to the solvent being at least 1:0.70, preferably 1:1-2, to crystallize the complex.The method provides a highly stable, amorphous crystalline product.

Abstract: The present invention relates to a method for purifying silica waste obtained in the manufacture of aluminium fluoride from hexafluosilicic acid and aluminium hydroxide, whereby the silica, is subjected to an acidic leaching at a pH below 3 to leach out part of the fluorine and substantially all the aluminium present in said waste, and is thereafter subjected to an alkaline leaching at pH 8.5-11.5 to leach out remaining fluorine present in said waste. The leachings are preferably carried out at elevated temperatures, normally 60.degree.-90.degree. C., and for a time sufficient to considerably reduce the contents of aluminium and fluorine, normally 1-3 hrs.The silica obtained is highly reactive and can be used as such or transformed into sodium silicate by a reaction with sodium hydroxide. The contents of fluorine and aluminium can be transferred to a process for the production of cryolite or similar compounds.

Abstract: The present invention relates to a method for producing lightweight granules of sodium tripolyphosphate from a powderous sodium-phosphate mixture. The material is first processed in the schugi-mixer, while adding a given quantity of water thereto, whereafter the moist mixture is fed to a rotating calcining furnace, to which the given, remaining quantity of water is supplied to the material prior to calcination.

Abstract: The invention relates to a method for controlling or monitoring the quality of copper cathodes. The method is characterized by stacking cathodes to form a bundle, preferably comprising 10-20 cathodes, and by determining the bulk density, or a value related thereto, of the bundle. The bulk volume or mean height of a cathode bundle can be used with great accuracy. Advantageously, the height of each cathode bundle is measured by means of distance-sensing means of the laser or ultrasonic type placed above the movement path of a cathode bundle.

Abstract: Liquid fuel, particularly slurry-type fuel, such as coal-water, slurry or coal-oil slurries, is atomized by bringing the fuel into contact with gas under pressure in an atomizing nozzle (1). To this end, a continuous stream of fuel is passed through a channel (17) of circular cross-section. The stream of fuel is accelerated in the channel, adjacent the outlet end of the nozzle, and is preliminarily disintegrated by means of at least one first stream of gas under pressure directed inwardly against the outside of the fuel stream. The fuel is finally atomized by directing at least one second stream of gas under pressure outwardly against the inside of the accelerated and preliminarily disintegrated fuel stream, substantially immediately after said stream exits from the nozzle.

Abstract: The present invention relates to storage-stable solutions of basic aluminium sulphate containing polynucleate aluminium hydroxide sulphate complexes of the formula[Al(OH).sub.x (SO.sub.4).sub.y (H.sub.2 O).sub.z ].sub.nin which x is 0.75-2.0; y is 0.5-1.12; 2x+y=3; and z is >>4, which solutions contain a stabilizing agent in the form of nitrilotriacetic acid, diethylene triaminopentaacetic acid and/or gallic acid.

Abstract: The invention relates to a method for continuously separating a hypoeutectic solution into two parts, of which parts, one comprises practically pure solvent and the other a solution which has a higher content of the dissolved substance than the original solution. In accordance with the invention, the starting solution is held in an elongate vessel at a temperature, which, at least at one end of the vessel, lies immediately above the melting point of the solvent, and cooling elements are caused to move in the vessel towards said one end thereof.

Abstract: A method for manufacturing sulphur-trioxide for the production of sulphuric acid from sulphur-dioxide containing gas, particularly furnace gas obtained from metallurgical processes by oxidation to sulphur trioxide in the presence of a catalyst and conversion of the sulphur trioxide to sulphuric acid. The sulphur dioxide is first separated from the gas preferably converted to liquid form and is then subsequent to being vaporized in a stoichiometric excess oxidized with oxygen.

Abstract: The invention relates to a method for producing blister copper from copper-iron sulphide concentrates, and particularly from concentrates whose sulphur content is insufficient to effect autogenous smelting of the concentrates to matte. The invention is characterized in that the concentrate, together with slag former, is smelted with oxygen-gas or air rich in oxygen in a top blown rotary converter, to form a mixture of a contaminated copper metal phase, magnetite and fayalite slag, whereafter a reductant, preferably coke, is supplied for the reduction of magnetite while supplying heat. After the reduction process, the slag is separated from the formed copper metal phase, which is then refined to blister copper in a manner known per se.

Abstract: The invention relates to a method for producing lead from sulphidic lead raw-materials by direct smelting processes of the kind in which the lead raw-materials are smelted autogenously in a shaft with the aid of oxygen gas, or air enriched in oxygen, optionally by adding fluxes, there being formed an oxide-containing molten product which is caused to pass into a coke bed arranged in the lower part of the shaft, to form a lead phase and a slag depleted in lead. The invention is characterized by heating the coke bed continuously, by partially combusting carbon therein and/or by supplying electrical energy thereto.The electrical heating is preferably effected by supplying electrical energy through induction or through electrodes.When heating the coke bed by the partial combustion of coke in the bed, oxygen gas or air enriched in oxygen is preferably introduced directly into the coke bed, through tuyeres or lances.