Abstract: The invention relates to ring furnaces of which at least one of the inner partitions is formed by a plurality of bricks made of refractory material including at least a first brick and a second brick placed above or below a third brick and separated from one another by a space of width J, in which the first brick has at least one recess on its assembly face opposite the third brick, the third brick has at least one projection on its assembly face facing the first brick, wherein the projection is inserted into the recess, the dimension E of said recess in the longitudinal direction of the partition is greater than the dimension B of said first projection in the same direction, and said recess is positioned at a determined distance Se from the end face adjacent to said space.

Abstract: An aluminum-based welding filler wire is made with an aluminum alloy that contains between 0.1 and 6 wt. % titanium, including one portion in the form of TiB2 particles, TiC particles, or a combination thereof, and another portion in the form of free titanium. The filler wire can be used in welding aluminum-based materials.

Abstract: The invention concerns a powdery product, of the type known as dry spray, for protecting centrifuge casting molds of cast iron pipes, comprising the usual components for this type of use, as well as an adjuvant for improving the flowability characteristics of said product when it is being deposited and make them less dependent on its physical or physico-chemical characteristics. Said adjuvant can be in particular silicone oil, potassium siliconate or micro-silica of density less than 0.1 g/cm3, as well as a mixture in any proportions of one or more of those.

Abstract: Aluminum alloy strips less than 0.3 mm thick for making heat exchangers, containing, in wt. %: Si<1.0, Fe<1.0, Cu<0.8, Mg<1.0, Mn?1.8, Zn<2.0, In<0.2, Sn<0.2, Bi<0.2, Ti<0.2, Cr<0.25, Zr<0.25, Si+Fe+Mn+Mg>0.8, other elements <0.05, each and <0.15 in total. The strips have between the surface and half the thickness a difference of corrosion potential, measured relative to a saturated calomel electrode in accordance with the ASTM G69 standard, of at least 10 mV. The invention also concerns a method for making such strips by continuous casting in conditions promoting formation of segregations in the strip core, optionally hot rolling, cold rolling optionally with one or several intermediate or final annealing(s) of 1 to 20 hours at a temperature between 200 and 450° C. The fins or separators made from the inventive strips have enhanced resistance to perforating corrosion.

Abstract: A process for the production of alumina trihydrate by alkaline digestion of bauxite using the Bayer process in which aluminate liquor and insoluble residues are separated using a solid/liquid separation device (E; W2; DC) characterised in that the said slurry (21a; 41; 230?) is at least partially passed through a hydrocyclone (H1; H21; H22; H3) to improve and accelerate the separation of the sodium aluminate liquor from the insoluble residues in the slurry (21a; 41; 230?) containing the said liquor and the said residues and that supplies or is derived from the said liquid-solid separation device. In a first embodiment, at least one hydrocyclone is used at the upstream side of the settler-thickener, as clarifier of the pregnant liquor. In a second embodiment, at least one hydrocyclone is used as a thickener of insoluble residue mud. In a third embodiment, a hydrocyclone is used in combination with the causticisation settler.

Abstract: Multilayer laminates useful in packaging of respiring food products and packages made therefrom. The laminates have a CO2 permeability rate of at least about 10 cm3/100 in2/24 hours and an O2 permeability rate of less than about 5.3 cm3/100 in2/24 hours.

Abstract: A Bayer process comprises grinding and then digestion of bauxite by bringing it into contact with a sodium aluminate liquor. Digestion consists of forming a slurry that is then treated to separate insoluble residues from the sodium aluminate liquor. The liquor is then crystallized and recycled back to green liquor after having been separated from the alumina trihydrate precipitated during crystallization. The process comprises a predesilication treatment during which the ground bauxite, before digestion, is brought into contact with an aqueous sodic solution that has a content of carbonates, sulphates and possibly chlorides which, expressed as a percentage related to the caustic concentration, has less than half of the corresponding impurities content of the spent liquor. Preferably, the pure caustic soda used to compensate for caustic soda losses in the Bayer circuit, previously injected just after evaporation, is now added in the aqueous sodic solution for the predesilication treatment.

Abstract: The purpose of this invention is a leak limiter (20) of an electrolytic cell (1) for the production of aluminum, fitted with confinement means comprising passage openings for the insertion of anode stems (3), characterized in that it comprises at least one support (21), capable of surrounding all or part of an anode stem, and at least one flexible sealing body (30, 30a, 30b, 30c) arranged around all or part of the periphery (23) of the support (21) and designed to close off all or some of the free space between the inside edge of an opening and an anode stem (3). This invention improves the leak tightness of covering means used in electrolytic cells.

Abstract: Process for the treatment of bauxite (10) by alkaline digestion, typically using the Bayer process in order to obtain alumina hydrate, characterized in that ground bauxite (11, 15) is added directly into an alkaline solution (21a) that is drawn off and that will be reinserted into the Bayer aluminate liquor circuit (20), the said alkaline solution (21a) being heated at a temperature such that after the said ground bauxite (11, 15) and the said alkaline solution have been brought into contact, the temperature of the slurry resulting from this mix is greater than a temperature close to the boiling temperature at atmospheric pressure, in other words typically greater than 95° C. and preferably greater than or equal to the boiling temperature at atmospheric pressure.

Abstract: This invention relates to a cathode element for use in a pot of an electrolytic cell intended for production of aluminum. The cathode element comprises a cathode block and a steel connection bar. The connection bar includes at least one metal insert, whose electrical conductivity is greater than the electrical conductivity of the said steel. The presence of an insert according to the invention can simultaneously result in a very large drop in the global cathode voltage and a very strong reduction in the current density at the head of the block.

Abstract: A powder product for the protection of centrifugal casting molds for cast iron pipes includes an inoculating metal alloy and possibly mineral powders, and a strongly reducing metal that is volatile at the temperature of the liquid cast iron. The use of products according to the invention prevents accumulation of dirt on molds and improves the surface condition of the cast iron pipes.

Abstract: The invention relates to an inoculant mixture for the treatment of molten cast iron, comprising 5 to 75% by weight of a ferro-silicon alloy of type A where Si/Fe>2, containing 0.005 to 3% by weight of rare earths, 0.005 to 3% bismuth, lead and/or antimony and less than 3% calcium, with a ratio (Bi+Pb+Sb)/TR of between 0.9 and 2.2 and 25 to 95% of at least one alloy of type B, based on silicon or ferro-silicon such that Si/Fe>2, containing calcium to a level such that the total amount of calcium in the mixture is from 0.3 to 3%. The above mixtures have a good granulometric stability over time and provide an efficient inoculation of cast pieces, in particular of thin pieces.

Abstract: A functional insert including a body which is provided with at least one flexible flange on the outer surface thereof, for creating a tight connection with the neck, and a functional element. The functional insert is characterised in that: a) it includes an adhesive which is typically carried by the flange and is selected in such a way that it adheres to the neck of the recipient, and b) the adhesive is typically a permanent adhesive selected in terms of its consistency or viscosity such that it only squeezes out under stress. In this way, any axial displacement towards the top of the functional insert is prevented by fixing the body to the neck of the recipient by means of an adhesive contact region.

Abstract: This invention relates to an anode assembly (1) to be used in a fused bath electrolysis aluminium production cell. This assembly comprises one inert anode (2) in the shape of a ladle, one connection conductor (3, 4, 5), mechanical connection means capable of cooperating so as to set up a mechanical link between the conductor and the anode, one metallic joint (31) that is or could be formed by brazing being located between all or part of at least one surface (20, 20?, 20?) of the open end (22) of the anode (2) and all or part of at least one surface (40, 40?, 40?) of the connection end (42) of the conductor (3, 4, 5). The invention simplifies manufacturing of anode assemblies comprising one inert anode.

Abstract: The invention relates to ring furnaces of which at least one of the inner partitions is formed by a plurality of bricks made of refractory material including at least a first brick (15a) and a second brick (15b) placed above or below a third brick (15c) and separated from one another by a space (13, 14) of width J, in which the first brick (15a) has at least one recess (158d, 158?d) on its assembly face opposite the third brick (15c), the third brick (15c) has at least one projection (155d, 155?d) on its assembly face facing the first brick (15a), wherein the projection is inserted into the recess, the dimension E of said recess (158d) in the longitudinal direction of the partition is greater than the dimension B of said first projection (155d) in the same direction, and said recess (158d) is positioned at a determined distance Se from the end face (152) adjacent to said space (13, 14).

Abstract: The invention relates to a cooling method of a igneous electrolytic cell for aluminium production wherein heat transfer fluid droplets (or “divided heat transfer fluid”) are produced, preferentially in a confined volume in contact with a specified surface of at least one wall of the shell of the pot of the electrolytic cell, so as to induce the evaporation of all or part of said droplets by contact with said surface and remove the heat from said surface. The invention also relates to a cooling system capable of implementing the cooling method. The invention makes it possible to obtain a high cooling efficiency due to the latent heat of vaporisation of the heat transfer fluid.

Abstract: The invention relates to a series (1) of electrolysis cells for the production of aluminum by fusion electrolysis, comprising at least two lines of cells, arranged transversely, an internal correction circuit (200) with at least one internal correction conductor (20, 20?) per line, adjacent to the neighboring line and a main connection circuit (400) between the final cells of the lines (101, 101?). In at least one line, the main connection circuit (400) comprises a layer of conductors, each conductor of which extends from the end of the final cell of the line to a given distance (D2, D2?) therefrom and the internal correction circuit (200) comprises a section of transverse conductors, arranged at a given distance (D1, D1?) from the final cell (101, 101?) running along the final cell for a given part L of the length thereof Lo. The invention permits a reduction in the mean supplementary vertical fields to very low values for electrolysis currents of a value greater than 300 kA.

Abstract: This invention relates to a method for controlling additions of powder materials into an electrolytic cell designed for the production of aluminium by fused bath electrolysis. The method according to the invention, which can easily be automated, can be used to maintain monitoring of operation of the feed even during anode effects.

Abstract: The present invention relates to a method of pre-heating a pot provided with anodes and cathodes for the production of aluminium by electrolysis, said method including a first step, prior to the pot being supplied with current, during which a layer of a granular conductive material is deposited then crushed between the anodes and the cathodes, characterized in that the granular conductive material is graphite-based and in that the layer of granular conductive material only extends, after crushing, over a part of a lower surface of each anode and takes the form of contact blocks.

Abstract: The present invention relates to an extruded, rolled and/or forged product made of an aluminum alloy. Alloys of the present invention may comprise (by mass): Zn 6.7-7.5% Cu 2.0-2.8% Mg 1.6-2.2% at least one element selected from the group composed of: i Zr 0.08-0.20% Cr 0.05-0.25% Sc 0.01-0.50% Hf 0.05-0.20% and V 0.02-0.20% Fe+Si<0.20% other elements ?0.05 each and ?0.15 total, balance aluminum. Products of the present invention in some embodiments have an improved compromise between static mechanical strength and damage tolerance.