WO2000046428A1 - Graphite cathode for electrolysis of aluminium - Google Patents
Graphite cathode for electrolysis of aluminium Download PDFInfo
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- WO2000046428A1 WO2000046428A1 PCT/FR2000/000234 FR0000234W WO0046428A1 WO 2000046428 A1 WO2000046428 A1 WO 2000046428A1 FR 0000234 W FR0000234 W FR 0000234W WO 0046428 A1 WO0046428 A1 WO 0046428A1
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- cathode
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
- C25C3/06—Electrolytic production, recovery or refining of metals by electrolysis of melts of aluminium
- C25C3/08—Cell construction, e.g. bottoms, walls, cathodes
Definitions
- the present invention relates to a graphite cathode for the electrolysis of aluminum.
- an electrolytic cell comprises, in a metal casing sheathed with refractories, a cathode sole composed of several juxtaposed cathode blocks.
- This assembly constitutes the crucible which, sealed by pot lining, is the seat of the transformation, under the action of the electric current, of the aluminum electrolytic bath.
- FIG. 1 A representation of an aluminum electrolysis cell is given in FIG. 1. Inside the enclosure of the tank, designated by the general reference 2, are arranged cathodes 3, each of which is connected to two cathode bars 4 emerging from its ends and passing through the tank. At-
- the cathode block is made from carbon material. These materials range from semi-graphite to graphite. They are shaped by extrusion or by vibro-massage after mixing the raw materials:
- the graphitization treatment of the graphite cathode allows the increase of the electrical and thermal conductivities, thus creating the conditions sufficient for an optimized operation of an ⁇ ⁇ electrolysis tank.
- Energy consumption decreases due to the decrease in the electrical resistance of the cathode.
- Another way to take advantage of this drop in electrical resistance is to increase the intensity of the current injected into the tank, thereby allowing an increase in aluminum production.
- the high value of the thermal conductivity of the cathode 15 then allows the evacuation of the excess heat generated by the increase in intensity.
- graphite cathode tanks appear less electrically unstable, that is to say with less fluctuation in electrical potentials, than carbon cathode tanks.
- the tanks fitted with graphite cathodes have a shorter lifespan than the tanks fitted with carbon cathodes.
- the graphite cathode tanks become unusable by too high an iron enrichment of the aluminum, which results from the attack of the cathode bar by the aluminum.
- the metal reaches the bar due to the erosion of the graphite block.
- erosion of the carbon cathodes is also observed, it is much lower and does not affect the life of the tanks which become unusable for other causes than erosion of the cathode.
- FIG. 2 of the appended schematic drawing shows a cathode block 3, with the cathode bars for supplying current 4, the initial profile of which is designated by the reference 8.
- the speed of erosion of a graphite cathode block is, therefore, its weak point, and its economic appeal in terms of production gain may disappear if the service life cannot be increased.
- curves A and B correspond respectively to the evolution of the current density in a carbon cathode and in a graphite cathode; It is quite clear that the variation in the current density between the ends and the middle of the cathode is much greater in the case of the graphite cathode, which increases its erosion.
- the object of the invention is to provide a graphite cathode whose lifetime is increased by limiting the erosion thereof, in particular in its end zones.
- the object of the invention is therefore to provide a cathode in which the current density is reduced at the ends.
- the cathode which it relates has a vertical electrical resistivity greater than the horizontal resistivity, the cathode being considered in a horizontal position in the interior of the electrolytic tank.
- the horizontal thermal conductivity which is higher the lower the resistivity, remains high and allows the evacuation of the calories generated in the tank.
- the higher vertical electrical resistivity allows a more homogeneous distribution of the current density.
- the ratio between the vertical and horizontal resistivities of the cathode is no longer equal to 1, the cathode is then anisotropic, (or orthotropic, if the resistivity in the third direction is equal to one of the other two).
- FIG. 1 Figure 2 of the accompanying schematic drawing shows what are the horizontal (H) and vertical (V) directions inside the tank.
- the ratio between the vertical resistivity and the horizontal resistivity is greater than 1, 3 and the vertical resistivity, measured at ambient temperature is greater than
- the cathode according to the invention is characterized in that it is produced from raw materials, at least some of which are anisotropic, and in that it is obtained by a shaping process favoring the alignment of the particles.
- the cathode can thus be obtained either by extrusion or vibrotassage.
- the orientation of the particles makes it possible to have different electrical resistivities in the horizontal direction and in the vertical direction. This orientation is carried out throughout the thickness of the product in order to optimize the increase in electrical resistance.
- the choice of coke and / or graphite grain makes it possible to adjust the degree of anisotropy desired for the resistivity characteristics. Coke can be chosen from the pitch coke or petroleum coke families. Several examples of graphite cathodes according to the invention are defined below. Example 1
- a graphite cathode of dimensions 450 * 500 * 3300mm, is manufactured from coke B: characteristic direction unit electrical resistivity * H // ⁇ .m 1 1, 3 electrical resistivity * V ⁇ .m 1 5.6 ratio (anisotropy ) 1, 38
- Example 2 A graphite cathode, of dimensions 450 * 500 * 3300mm, is manufactured from coke C: characteristic direction unit electrical resistivity * H ⁇ .m 1 1, 0 electrical resistivity * V ⁇ .m 1 8, 1 ratio (anisotropy ) 1, 65
- Curves C and D in FIG. 4 correspond to the evolution of the current density over the length of two graphite cathodes having the structures of Example 1 and Example 2 respectively.
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- Chemical Kinetics & Catalysis (AREA)
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- Organic Chemistry (AREA)
- Electrolytic Production Of Metals (AREA)
Abstract
The invention concerns a cathode having a vertical electrical resistivity higher than the horizontal resistivity, the cathode (3) being considered to be in a horizontal position inside the electrolytic cell.
Description
CATHODE GRAPHITE POUR L'ELECTROLYSE DE L'ALUMINIUM GRAPHITE CATHODE FOR ALUMINUM ELECTROLYSIS
La présente invention a pour objet une cathode graphite pour l 'électrolyse de l 'aluminium.The present invention relates to a graphite cathode for the electrolysis of aluminum.
Dans le procédé électrolytique utilisé dans la plupart des usines de 5 production d'aluminium, une cuve d'électrolyse comprend, dans un caisson métallique gainé de réfractaires, une sole cathodique composée de plusieurs blocs cathodiques juxtaposés. Cet ensemble constitue le creuset qui, rendu étanche par de la pâte de brasque, est le siège de la transformation, sous l'action du courant électrique, du bain électrolytique en aluminium. CetteIn the electrolytic process used in most aluminum production plants, an electrolytic cell comprises, in a metal casing sheathed with refractories, a cathode sole composed of several juxtaposed cathode blocks. This assembly constitutes the crucible which, sealed by pot lining, is the seat of the transformation, under the action of the electric current, of the aluminum electrolytic bath. This
Ό réaction a lieu à une température supérieure en général à 950° C. Une représentation d 'une cuve d'électrolyse d'aluminium est donnée sur la figure 1 . A l'intérieur de l'enceinte de la cuve, désignée par la référence générale 2, sont disposées des cathodes 3, dont chacune est reliée à deux barres cathodiques 4 sortant de ses extrémités et traversant la cuve. Au-Ό reaction takes place at a temperature generally higher than 950 ° C. A representation of an aluminum electrolysis cell is given in FIG. 1. Inside the enclosure of the tank, designated by the general reference 2, are arranged cathodes 3, each of which is connected to two cathode bars 4 emerging from its ends and passing through the tank. At-
1 5 dessus des cathodes 3 se trouvent l'aluminium 5 et le bain électrolytique 6 dans lequel plongent des anodes 7. Le courant entre par l'anode sur le dessus de la cuve, traverse le bain, le métal et la cathode et sort sur les côtés de la cuve par les barres cathodiques.1 5 above the cathodes 3 are the aluminum 5 and the electrolytic bath 6 in which anodes are immersed 7. The current enters through the anode on the top of the tank, crosses the bath, the metal and the cathode and exits on the sides of the tank by the cathode bars.
Pour résister aux conditions thermiques et chimiques prévalant lorsTo withstand the thermal and chemical conditions prevailing during
20 du fonctionnement de la cuve et satisfaire à la nécessité de conduction du courant d'électrolyse, le bloc cathodique est fabriqué à partir de matériau carboné. Ces matériaux vont du semi-graphitique au graphite. Ils sont mis en forme par extrusion ou par vibrotassage après malaxage des matières premières :20 of the operation of the cell and meet the need for conduction of the electrolysis current, the cathode block is made from carbon material. These materials range from semi-graphite to graphite. They are shaped by extrusion or by vibro-massage after mixing the raw materials:
25 • soit un mélange de brai, d'anthracite calciné et/ou de graphite dans le cas des matériaux semi-graphitiques et graphitiques. Ces matériaux sont ensuite cuits à environ 1 200° C. La cathode graphitique ne contient pas d'anthracite. La cathode fabriquée à partir de ces matériaux est communément appelée cathode carbone,25 • or a mixture of pitch, calcined anthracite and / or graphite in the case of semi-graphitic and graphitic materials. These materials are then baked at around 1,200 ° C. The graphite cathode does not contain anthracite. The cathode made from these materials is commonly called a carbon cathode,
'.'0 • soit un mélange de brai, de coke avec ou sans graphite dans le cas des graphites. Dans ce cas les matériaux sont cuits à environ 800° C, puis graphitisés à plus de 2 400° C. Cette cathode est appelée cathode graphite.
Il est connu d 'utiliser des cathodes carbone, qui cependant ont des caractéristiques électriques et thermiques moyennes, ne convenant plus aux conditions de fonctionnement des cuves modernes, notamment de forte intensité de courant. La nécessité de réduire la consommation d'énergie, et la 5 possibilité d'augmenter l'intensité du courant, notamment dans des installations existantes, a promu l'utilisation des cathodes graphite. ' .'0 • or a mixture of pitch, coke with or without graphite in the case of graphites. In this case, the materials are baked at around 800 ° C, then graphitized at over 2400 ° C. This cathode is called a graphite cathode. It is known to use carbon cathodes, which however have average electrical and thermal characteristics, which are no longer suitable for the operating conditions of modern tanks, in particular of high current intensity. The need to reduce energy consumption, and the possibility of increasing the intensity of the current, especially in existing installations, has promoted the use of graphite cathodes.
Le traitement de graphitisation de la cathode graphite, à plus de 2 400° C, permet l'augmentation des conductivités électrique et thermique, créant ainsi les conditions suffisantes à un fonctionnement optimisé d'une ι θ cuve d'électrolyse. La consommation d'énergie diminue en raison de la baisse de la résistance électrique de la cathode. Une autre façon de profiter de cette baisse de résistance électrique consiste à augmenter l'intensité du courant injecté dans la cuve, permettant ainsi une augmentation de la production d'aluminium. La valeur élevée de la conductibilité thermique de la cathode 15 permet alors l'évacuation de l 'excès de chaleur généré par l'augmentation d'intensité. De plus, les cuves à cathode graphite apparaissent moins instables électriquement, c'est-à-dire comportant moins de fluctuation des potentiels électriques, que les cuves à cathodes carbone.The graphitization treatment of the graphite cathode, at more than 2400 ° C., allows the increase of the electrical and thermal conductivities, thus creating the conditions sufficient for an optimized operation of an ι θ electrolysis tank. Energy consumption decreases due to the decrease in the electrical resistance of the cathode. Another way to take advantage of this drop in electrical resistance is to increase the intensity of the current injected into the tank, thereby allowing an increase in aluminum production. The high value of the thermal conductivity of the cathode 15 then allows the evacuation of the excess heat generated by the increase in intensity. In addition, graphite cathode tanks appear less electrically unstable, that is to say with less fluctuation in electrical potentials, than carbon cathode tanks.
Toutefois, il s'est révélé que les cuves équipées de cathodes 0 graphite présentent une durée de vie plus faible que les cuves équipées de cathodes carbone. Les cuves à cathodes graphite deviennent inutilisables par un enrichissement trop élevé en fer de l'aluminium, qui résulte de l'attaque de la barre cathodique par l'aluminium. Le métal atteint la barre par suite de l'érosion du bloc graphite. Bien qu 'une érosion des cathodes carbone soit 5 également constatée, elle est beaucoup plus faible et n'altère pas la durée de vie des cuves qui deviennent inutilisables pour d 'autres causes que l'érosion de la cathode.However, it has been found that the tanks fitted with graphite cathodes have a shorter lifespan than the tanks fitted with carbon cathodes. The graphite cathode tanks become unusable by too high an iron enrichment of the aluminum, which results from the attack of the cathode bar by the aluminum. The metal reaches the bar due to the erosion of the graphite block. Although erosion of the carbon cathodes is also observed, it is much lower and does not affect the life of the tanks which become unusable for other causes than erosion of the cathode.
Au contraire, l'usure des cathodes graphite est suffisamment rapide pour devenir la première cause de mortalité des cuves d'électrolyse de 0 l'aluminium à un âge que l'on peut qualifier de précoce par rapport aux durées de vie enregistrées pour les cuves équipées de cathodes carbone. Ainsi on enregistre les vitesses d'usure suivantes pour les différents matériaux :
Cathode vitesse d'usure (mm/an)On the contrary, the wear of graphite cathodes is fast enough to become the first cause of death in aluminum electrolysis cells at an age that can be described as early compared to the lifetimes recorded for the cells. fitted with carbon cathodes. The following wear rates are therefore recorded for the different materials: Cathode wear rate (mm / year)
Carbone, semi-graphitique 10-20Carbon, semi-graphitic 10-20
Carbone, graphitique 20-40 graphite 40-80Carbon, graphitic 20-40 graphite 40-80
55
La figure 2 du dessin schématique annexé montre un bloc cathodique 3, avec les barres cathodiques d'amenée de courant 4, dont le profil initial est désigné par la référence 8. Le profil d'érosion 9, représenté en pointillés, montre que cette érosion est accentuée aux extrémités du bloc ι o cathodique.FIG. 2 of the appended schematic drawing shows a cathode block 3, with the cathode bars for supplying current 4, the initial profile of which is designated by the reference 8. The erosion profile 9, shown in dotted lines, shows that this erosion is highlighted at the ends of the cathode block.
La vitesse d'érosion d'un bloc cathodique graphite est, par conséquent, son point faible, et son attrait économique en terme de gain de production peut disparaître si la durée de vie ne peut pas être augmentée.The speed of erosion of a graphite cathode block is, therefore, its weak point, and its economic appeal in terms of production gain may disappear if the service life cannot be increased.
Le calcul de la distribution du courant montre une concentrationThe calculation of the current distribution shows a concentration
' 5 des lignes de courant vers l'extrémité de la cathode comme représentée sur la figure 3 sur laquelle par symétrie seule une demi-cathode est traitée. Par suite les densités de courant dans la cathode sont plus élevées du côté de la sortie des barres cathodiques comme représentée sur la figure 4, qui représente la variation de la densité de courant d, représentée en ordonnée, 0 en fonction de la distance entre une extrémité de la cathode et le milieu de celle-ci, représentée en abscisse de 0 à 100. Ces densités de courant sont d'autant plus élevées que la résistance électrique de la cathode est faible. Ainsi le profil d'érosion de chaque cathode, et notamment les fortes usures observées aux extrémités des cathodes correspondent aux zones de fortes 5 densités de courant dans la cathode.'5 of the current lines towards the end of the cathode as shown in Figure 3 in which by symmetry only half a cathode is treated. Consequently, the current densities in the cathode are higher on the side of the output of the cathode bars as represented in FIG. 4, which represents the variation of the current density d, represented on the ordinate, 0 as a function of the distance between a end of the cathode and the middle thereof, shown on the abscissa from 0 to 100. These current densities are higher the lower the electrical resistance of the cathode. Thus the erosion profile of each cathode, and in particular the high wear observed at the ends of the cathodes correspond to the zones of high current densities in the cathode.
Sur la figure 4 les courbes A et B correspondent respectivement à l'évolution de la densité de courant dans une cathode carbone et dans une cathode graphite ; Il est tout à fait clair que la variation de la densité de courant entre les extrémités et le milieu de la cathode est beaucoup plus 0 importante dans le cas de la cathode graphite, ce qui augmente son érosion. Le but de l'invention est de fournir une cathode graphite dont la durée de vie soit augmentée en limitant l'érosion de celle-ci, notamment dans
ses zones d'extrémité. Le but de l'invention est donc de fournir une cathode dans laquelle la densité de courant soit diminuée aux extrémités.In FIG. 4, curves A and B correspond respectively to the evolution of the current density in a carbon cathode and in a graphite cathode; It is quite clear that the variation in the current density between the ends and the middle of the cathode is much greater in the case of the graphite cathode, which increases its erosion. The object of the invention is to provide a graphite cathode whose lifetime is increased by limiting the erosion thereof, in particular in its end zones. The object of the invention is therefore to provide a cathode in which the current density is reduced at the ends.
A cet effet, la cathode qu 'elle concerne, possède une résistivité électrique verticale supérieure à la résistivité horizontale, la cathode étant considérée en position horizontale' à l'intérieur de la cuve d'électrolyse.To this end, the cathode which it relates has a vertical electrical resistivity greater than the horizontal resistivity, the cathode being considered in a horizontal position in the interior of the electrolytic tank.
En conservant une résistivité horizontale faible, la conductibilité thermique horizontale, qui est d'autant plus grande que la résistivité est faible, reste élevée et permet l'évacuation des calories générées dans la cuve. La résistivité électrique verticale plus élevée permet une distribution plus homogène de la densité de courant. Le rapport entre les resistivites verticale et horizontale de la cathode n'est plus égal à 1 , la cathode est alors anisotrope, (ou orthotrope, si la résistivité dans la troisième direction est égale à l'une des deux autres).By keeping a low horizontal resistivity, the horizontal thermal conductivity, which is higher the lower the resistivity, remains high and allows the evacuation of the calories generated in the tank. The higher vertical electrical resistivity allows a more homogeneous distribution of the current density. The ratio between the vertical and horizontal resistivities of the cathode is no longer equal to 1, the cathode is then anisotropic, (or orthotropic, if the resistivity in the third direction is equal to one of the other two).
La figure 2 du dessin schématique annexé montre ce que sont les directions horizontale (H) et verticale (V) à l'intérieur de la cuve.Figure 2 of the accompanying schematic drawing shows what are the horizontal (H) and vertical (V) directions inside the tank.
Suivant une caractéristique avantageuse de l'invention, le rapport entre la résistivité verticale et la résistivité horizontale est supérieur à 1 ,3 et la résistivité verticale, mesurée à température ambiante est supérieure àAccording to an advantageous characteristic of the invention, the ratio between the vertical resistivity and the horizontal resistivity is greater than 1, 3 and the vertical resistivity, measured at ambient temperature is greater than
13 μΩ.m. Afin d'obtenir une différence entre la résistivité électrique verticale et la résistivité horizontale, la cathode selon l'invention est caractérisée en ce qu'elle est réalisée à partir de matières premières, dont au moins certaines sont anisotropes, et en ce qu'elle est obtenue par un procédé de mise en forme favorisant l'alignement des particules. La cathode peut ainsi être obtenue soit par extrusion ou vibrotassage. L'orientation des particules permet de disposer de resistivites électriques différentes dans la direction horizontale et dans la direction verticale. Cette orientation est réalisée dans toute l'épaisseur du produit afin d'optimiser l'augmentation de la résistance électrique. Le choix du coke et/ou du grain graphite permet d 'ajuster le degré d'anisotropie désiré pour les caractéristiques de résistivité. Le coke peut être choisi dans les familles de coke de brai ou de coke de pétrole. Plusieurs exemples de cathodes graphite selon l'invention sont définies ci-après.
Exemple 113 μΩ.m. In order to obtain a difference between the vertical electrical resistivity and the horizontal resistivity, the cathode according to the invention is characterized in that it is produced from raw materials, at least some of which are anisotropic, and in that it is obtained by a shaping process favoring the alignment of the particles. The cathode can thus be obtained either by extrusion or vibrotassage. The orientation of the particles makes it possible to have different electrical resistivities in the horizontal direction and in the vertical direction. This orientation is carried out throughout the thickness of the product in order to optimize the increase in electrical resistance. The choice of coke and / or graphite grain makes it possible to adjust the degree of anisotropy desired for the resistivity characteristics. Coke can be chosen from the pitch coke or petroleum coke families. Several examples of graphite cathodes according to the invention are defined below. Example 1
Une cathode graphite, de dimensions 450*500*3300mm, est fabriquée à partir de coke B : caractéristique direction unité résistivité électrique* H //Ω.m 1 1 ,3 résistivité électrique* V μΩ.m 1 5,6 rapport (anisotropie) 1 ,38A graphite cathode, of dimensions 450 * 500 * 3300mm, is manufactured from coke B: characteristic direction unit electrical resistivity * H //Ω.m 1 1, 3 electrical resistivity * V μΩ.m 1 5.6 ratio (anisotropy ) 1, 38
H : direction horizontale dans la cuveH: horizontal direction in the tank
V : direction verticale dans la cuveV: vertical direction in the tank
* mesurée à la température ambiante* measured at room temperature
Exemple 2 Une cathode graphite, de dimensions 450*500*3300mm, est fabriquée à partir de coke C : caractéristique direction unité résistivité électrique* H μΩ.m 1 1 ,0 résistivité électrique* V μΩ.m 1 8, 1 rapport (anisotropie) 1 ,65Example 2 A graphite cathode, of dimensions 450 * 500 * 3300mm, is manufactured from coke C: characteristic direction unit electrical resistivity * H μΩ.m 1 1, 0 electrical resistivity * V μΩ.m 1 8, 1 ratio (anisotropy ) 1, 65
H : direction horizontale dans la cuveH: horizontal direction in the tank
V : direction verticale dans la cuveV: vertical direction in the tank
* mesurée à la température ambiante Les courbes C et D de la figure 4 correspondent à l'évolution de la densité de courant sur la longueur de deux cathodes graphite ayant les structures respectivement de l'exemple 1 et de l'exemple 2.* measured at room temperature Curves C and D in FIG. 4 correspond to the evolution of the current density over the length of two graphite cathodes having the structures of Example 1 and Example 2 respectively.
Comme il ressort de ce qui précède, une telle cathode apporte une grande amélioration à la technique existante, car tout en conservant les avantages d'une cathode graphite traditionnelle en terme de conductivités électrique et thermique horizontales élevées, elle permet de réduire la densité de courant dans les zones d'extrémité de la cathode avec, pour conséquence, une meilleure résistance à l'érosion et, par suite, une durée de vie accrue.
As is clear from the above, such a cathode brings a great improvement to the existing technique, because while retaining the advantages of a traditional graphite cathode in terms of high horizontal electrical and thermal conductivities, it makes it possible to reduce the current density in the end zones of the cathode with, as a consequence, better resistance to erosion and, consequently, an increased service life.
Claims
1 . Cathode graphite pour électrolyse de l'aluminium, caractérisée en ce qu'elle possède une résistivité électrique verticale supérieure à la résistivité horizontale, la cathode (3) étant considérée en position horizontale à l'intérieur de la cuve d'électrolyse.1. Graphite cathode for aluminum electrolysis, characterized in that it has a vertical electrical resistivity greater than the horizontal resistivity, the cathode (3) being considered in a horizontal position inside the electrolysis tank.
2. Cathode graphite selon la revendication 1 , caractérisée en ce que le rapport entre la résistivité verticale et la résistivité horizontale est supérieur à 1 ,3 et en ce que la résistivité verticale, mesurée à la température ambiante est supérieure à 13μΩ.m. 2. Graphite cathode according to claim 1, characterized in that the ratio between the vertical resistivity and the horizontal resistivity is greater than 1, 3 and in that the vertical resistivity, measured at ambient temperature is greater than 13μΩ.m.
3. Cathode graphite selon l'une quelconque des revendications 1 et 2, caractérisée en ce qu'elle est réalisée à partir de matières premières, dont au moins certaines sont anisotropes, et en ce qu'elle est obtenue par extrusion ou vibrotassage.3. Graphite cathode according to any one of claims 1 and 2, characterized in that it is made from raw materials, at least some of which are anisotropic, and in that it is obtained by extrusion or vibrotassage.
4. Cathode graphite selon la revendication 3, caractérisée en ce que les matières premières anisotropes sont choisies parmi les cokes de brai et de pétrole. 4. Graphite cathode according to claim 3, characterized in that the anisotropic raw materials are chosen from pitch and petroleum cokes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AU23014/00A AU2301400A (en) | 1999-02-02 | 2000-02-01 | Graphite cathode for electrolysis of aluminium |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR9901321A FR2789092B1 (en) | 1999-02-02 | 1999-02-02 | GRAPHIC CATHODE FOR ALUMINUM ELECTROLYSIS |
| FR99/01321 | 1999-02-02 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2000046428A1 true WO2000046428A1 (en) | 2000-08-10 |
Family
ID=9541621
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/FR2000/000234 WO2000046428A1 (en) | 1999-02-02 | 2000-02-01 | Graphite cathode for electrolysis of aluminium |
Country Status (3)
| Country | Link |
|---|---|
| AU (1) | AU2301400A (en) |
| FR (1) | FR2789092B1 (en) |
| WO (1) | WO2000046428A1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1233083A1 (en) * | 2001-02-14 | 2002-08-21 | Alcan Technology & Management AG | Carbon bottom of electrolysis cell used in the production of aluminum |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4121983A (en) * | 1977-12-21 | 1978-10-24 | Aluminum Company Of America | Metal production |
-
1999
- 1999-02-02 FR FR9901321A patent/FR2789092B1/en not_active Expired - Lifetime
-
2000
- 2000-02-01 WO PCT/FR2000/000234 patent/WO2000046428A1/en active Application Filing
- 2000-02-01 AU AU23014/00A patent/AU2301400A/en not_active Abandoned
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4121983A (en) * | 1977-12-21 | 1978-10-24 | Aluminum Company Of America | Metal production |
Also Published As
| Publication number | Publication date |
|---|---|
| FR2789092A1 (en) | 2000-08-04 |
| AU2301400A (en) | 2000-08-25 |
| FR2789092B1 (en) | 2001-03-09 |
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