CA2470644A1 - Process for producing cathode blocks - Google Patents
Process for producing cathode blocks Download PDFInfo
- Publication number
- CA2470644A1 CA2470644A1 CA002470644A CA2470644A CA2470644A1 CA 2470644 A1 CA2470644 A1 CA 2470644A1 CA 002470644 A CA002470644 A CA 002470644A CA 2470644 A CA2470644 A CA 2470644A CA 2470644 A1 CA2470644 A1 CA 2470644A1
- Authority
- CA
- Canada
- Prior art keywords
- cathode
- length
- cathode block
- blocks
- graphitization
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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Classifications
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/515—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics
- C04B35/52—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxide ceramics based on carbon, e.g. graphite
- C04B35/522—Graphite
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Ceramic Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Metallurgy (AREA)
- Manufacturing & Machinery (AREA)
- Structural Engineering (AREA)
- Electrolytic Production Of Metals (AREA)
Abstract
The invention relates to a method for graphiting carbonised cathode blocks, whereby the graphiting is at least partly achieved by inductive heating of the cathode block, the inductively-heated zone is located in the middle of the length of the cathode block, the cathode blocks produced thus and use thereof for the electrolytic extraction of aluminium.
Description
SGL CARBON AG
Process for producing cathode blocks The invention relates to a process for producing cathode blocks, particularly for the electrolytic production of aluminum.
In the electrolytic production of aluminum by the Hall-Heroult process, use is made of electrolysis cells which have a bottom which is made up of a plurality of blocks and acts as cathode. The electrolyte is a melt, comprising mainly a solution of aluminum oxide in cryolite. The working temperature is, for example, about 1 000 °C. The electrolytically generated molten aluminum is deposited on the bottom of the cell under a layer of the electrolyte. The cells are surrounded by a metallic housing (preferably steel) lined with high-temperature-resistant material.
Due to the chemical resistance and thermal stability required, the material of choice for the cathode blocks is preferably carbon which may have been partially or completely graphitized by means of thermal treatment.
Such cathode blocks are produced by mixing pitches, cokes, anthracite and/or graphite in selected particle sizes or particle size distributions for the solids and shaping, firing and, if appropriate, (partially) graphi tizing the mixtures. Firing (carbonization) is usually carried out at temperatures of about 1 200 °C, and the graphitization is usually carried out at temperatures above 2 400 °C.
While graphitized cathodes are preferred because of their higher electrical conductivity, they suffer from increased corrosion during operation, corresponding to a mean annual decrease in their thickness of up to 80 mm.
This corrosion is not distributed unifarmly over the length of the cathode blocks (corresponding to the width of the cell), but the surface of the cathode blocks is changed to a W-shaped profile. Due to the nonuniform removal of material, the useful life of the cathode blocks is limited by the areas having the greatest erosion.
One possible way of making the erosion more uniform over the length of the cathode block and thus increasing the useful life is to configure the cathode blocks so that their electrical resistance varies over the length in such a way that the current density (and thus the c~a, ro~sion) isp uniform ~wover _-thei,x.,-1-ength or.__..at-.,-_least --._._-.~,. -..~.--.--. - ..
displays a very small deviation from its mean over t'he length.
One solution for this problem is described in DE 20 61 263, in which composite cathodes are made up of either a plurality of carbon blocks which have different electrical conductivities and are arranged so that a uniform or approximately uniform current distribution results, or of carbon blocks whose electrical resistances increase continuously in the direction of the cathodic terminals. 'The number of carbon blocks and their electrical resistance depend in each case on the size and type of the cell and have to be adapted individually for each case. Cathode blocks made up of a plurality of individual carbon blocks are complicated~to construct;
the joins also have to be sealed well in order to prevent the liquid aluminum flowing out at the joins:
~, 2a_ 20 One solution is described in DE 20 61 263, in which composite cathodes are made up of either a plurality of carbon blocks which have different electrical conduc-tivities and are arranged so that a uniform or approxi-mately uniform current distribution results, or of carbon blocks whose electrical resistances increase continuously in the direction of the cathodic terminals. The number of carbon blocks and their electrical resistance depend in each case on the size and type of the cell and have to be calculated afresh for each case. Cathode blocks made up of a plurality of individual carbon blocks are complicated to construct;
the joins also have to be sealed well in order to prevent the liquid aluminum flowing out at the joins.
AMENDED SHEET
least displays a very small deviation from its mean over the length.
Process for producing cathode blocks The invention relates to a process for producing cathode blocks, particularly for the electrolytic production of aluminum.
In the electrolytic production of aluminum by the Hall-Heroult process, use is made of electrolysis cells which have a bottom which is made up of a plurality of blocks and acts as cathode. The electrolyte is a melt, comprising mainly a solution of aluminum oxide in cryolite. The working temperature is, for example, about 1 000 °C. The electrolytically generated molten aluminum is deposited on the bottom of the cell under a layer of the electrolyte. The cells are surrounded by a metallic housing (preferably steel) lined with high-temperature-resistant material.
Due to the chemical resistance and thermal stability required, the material of choice for the cathode blocks is preferably carbon which may have been partially or completely graphitized by means of thermal treatment.
Such cathode blocks are produced by mixing pitches, cokes, anthracite and/or graphite in selected particle sizes or particle size distributions for the solids and shaping, firing and, if appropriate, (partially) graphi tizing the mixtures. Firing (carbonization) is usually carried out at temperatures of about 1 200 °C, and the graphitization is usually carried out at temperatures above 2 400 °C.
While graphitized cathodes are preferred because of their higher electrical conductivity, they suffer from increased corrosion during operation, corresponding to a mean annual decrease in their thickness of up to 80 mm.
This corrosion is not distributed unifarmly over the length of the cathode blocks (corresponding to the width of the cell), but the surface of the cathode blocks is changed to a W-shaped profile. Due to the nonuniform removal of material, the useful life of the cathode blocks is limited by the areas having the greatest erosion.
One possible way of making the erosion more uniform over the length of the cathode block and thus increasing the useful life is to configure the cathode blocks so that their electrical resistance varies over the length in such a way that the current density (and thus the c~a, ro~sion) isp uniform ~wover _-thei,x.,-1-ength or.__..at-.,-_least --._._-.~,. -..~.--.--. - ..
displays a very small deviation from its mean over t'he length.
One solution for this problem is described in DE 20 61 263, in which composite cathodes are made up of either a plurality of carbon blocks which have different electrical conductivities and are arranged so that a uniform or approximately uniform current distribution results, or of carbon blocks whose electrical resistances increase continuously in the direction of the cathodic terminals. 'The number of carbon blocks and their electrical resistance depend in each case on the size and type of the cell and have to be adapted individually for each case. Cathode blocks made up of a plurality of individual carbon blocks are complicated~to construct;
the joins also have to be sealed well in order to prevent the liquid aluminum flowing out at the joins:
~, 2a_ 20 One solution is described in DE 20 61 263, in which composite cathodes are made up of either a plurality of carbon blocks which have different electrical conduc-tivities and are arranged so that a uniform or approxi-mately uniform current distribution results, or of carbon blocks whose electrical resistances increase continuously in the direction of the cathodic terminals. The number of carbon blocks and their electrical resistance depend in each case on the size and type of the cell and have to be calculated afresh for each case. Cathode blocks made up of a plurality of individual carbon blocks are complicated to construct;
the joins also have to be sealed well in order to prevent the liquid aluminum flowing out at the joins.
AMENDED SHEET
least displays a very small deviation from its mean over the length.
US 4,071,604 describes the graphitization of a carbon body in an induction furnace, with the latter being the only source of heat.
WO 00/46426 describes a graphite cathode consisting of a single block which has an electrical conductivity which can be changed over its length, with the conductivity being lower at the ends of the block than in the middle. This nonuniform distribution of electrical conductivity is achieved by bringing the end zones to a temperature of from 2 200 to 2 500 'C during the graphitization, while the middle zone is exposed to a temperature of from 2 700 to 3 000 'C. This different heat treatment can be achieved in two ways according to these teachings: on the one hand, the loss of heat by conduction in the graphitization furnace can be limited differently, or heat sinks can be provided in the vicinity of the end zones so as to increase the heat loss. In the case of a transverse graphitization, the density of the thermally insulating bed is altered so that the heat loss over the length of the cathodes becomes nonuniform and the desired temperatures are obtained as a result. In the case of longitudinal graphitization, too, the heat loss in the vicinity of the ends can be increased by different configuration of the thermally insulating bed, or bodies which conduct heat away, preferably graphite bodies, are installed for this purpose in their vicinity so as to produce greater outward heat flow to the furnace wall.
According to another method, the difference in the heat treatment can be achieved by local changes in the current density, with the result of different heat evolution.
AMENDED SHEET
- 3,~ -In WO 00/46426, a graphite cathode is described consl ting of a single block which has an electrical conduc 'vity which is varied over its length, with the conducti ' ty being lower at the ends of the block than in the middle. This nonuniform distribution of electrical conductivity 's achieved by bringing the end zones to a temperature o from 2 200 to 2 500 °C during graphitization, w ile the middle zone is exposed to a temperature of from 2 700 to 3 000 °C. This different heat treatment can be chieved in two ways according to these teachings : on tYi'e one hand, heat loss in the graphitization furnace cai~, be limited differently, or heat sinks can be providedl~'~~n the vicinity of the end zones so as to increase the heft loss. In the case of a transverse graphitization, the density of the thermally insulating bed is altered so that the heat loss over the length of the cathodes becomes nonur~iform and the desired temperatures are obtained as a result. In the case of longitudinal graphitization, too, the heat loss in the vicinity of the ends can be increased by different configuration of the thermally insulating bed, or bodies which carry away the heat, preferably graphite bodies, are installed for this purpose in their vicini y so as to produce greater outward heat flow to the furnad.e wall.
According to another method, the difference inv heat treatment can be achieved by local changes in the current r'density, with the result of different heat ev~o-lu-ti.
This change in the current density can, according to the teachings, be achieved by different resistances of the conductive bed between two cathodes in an Acheson furnace (transverse graphitization); no such solution is indica ted for a longitudinal graphitization process.
WO 00/46426 describes a graphite cathode consisting of a single block which has an electrical conductivity which can be changed over its length, with the conductivity being lower at the ends of the block than in the middle. This nonuniform distribution of electrical conductivity is achieved by bringing the end zones to a temperature of from 2 200 to 2 500 'C during the graphitization, while the middle zone is exposed to a temperature of from 2 700 to 3 000 'C. This different heat treatment can be achieved in two ways according to these teachings: on the one hand, the loss of heat by conduction in the graphitization furnace can be limited differently, or heat sinks can be provided in the vicinity of the end zones so as to increase the heat loss. In the case of a transverse graphitization, the density of the thermally insulating bed is altered so that the heat loss over the length of the cathodes becomes nonuniform and the desired temperatures are obtained as a result. In the case of longitudinal graphitization, too, the heat loss in the vicinity of the ends can be increased by different configuration of the thermally insulating bed, or bodies which conduct heat away, preferably graphite bodies, are installed for this purpose in their vicinity so as to produce greater outward heat flow to the furnace wall.
According to another method, the difference in the heat treatment can be achieved by local changes in the current density, with the result of different heat evolution.
AMENDED SHEET
- 3,~ -In WO 00/46426, a graphite cathode is described consl ting of a single block which has an electrical conduc 'vity which is varied over its length, with the conducti ' ty being lower at the ends of the block than in the middle. This nonuniform distribution of electrical conductivity 's achieved by bringing the end zones to a temperature o from 2 200 to 2 500 °C during graphitization, w ile the middle zone is exposed to a temperature of from 2 700 to 3 000 °C. This different heat treatment can be chieved in two ways according to these teachings : on tYi'e one hand, heat loss in the graphitization furnace cai~, be limited differently, or heat sinks can be providedl~'~~n the vicinity of the end zones so as to increase the heft loss. In the case of a transverse graphitization, the density of the thermally insulating bed is altered so that the heat loss over the length of the cathodes becomes nonur~iform and the desired temperatures are obtained as a result. In the case of longitudinal graphitization, too, the heat loss in the vicinity of the ends can be increased by different configuration of the thermally insulating bed, or bodies which carry away the heat, preferably graphite bodies, are installed for this purpose in their vicini y so as to produce greater outward heat flow to the furnad.e wall.
According to another method, the difference inv heat treatment can be achieved by local changes in the current r'density, with the result of different heat ev~o-lu-ti.
This change in the current density can, according to the teachings, be achieved by different resistances of the conductive bed between two cathodes in an Acheson furnace (transverse graphitization); no such solution is indica ted for a longitudinal graphitization process.
These known methods have considerable disadvantages for industrial use. A difference of 500 °C in the desired graphitization temperatures in the middle and at the ends of the cathodes cannot be achieved by means of heat sinks alone. The required difference in heat conduction to the outside results in a considerable energy loss which significantly increases the costs of manufacture. The higher heat loss towards the furnace walls also means a higher thermal load which makes the construction of the furnace more expensive or reduces its life. Finally, an inhomogeneity in the thermally insulating bed or the conductive bed is not very practical, since the bed material would have to be introduced in a plurality of steps and would have to be classified again according to its thermal or electrical conductivity after the furnace cycle is terminated and the cathodes are removed.
It is therefore an object of the present invention to provide a practical process for producing cathodes with an electrical conductivity varying along their length.
This object is achieved according to the invention by an additional inductive heating of the cathode blocks.
The invention accordingly provides a process for produc-ing cathode blocks which can be used for the electrolytic production of aluminum, which comprises carrying out a longitudinal graphitization of carbonized.cathode blocks and effecting the graphitization at least partly by inductive heating of the cathode block, with the inductively heated zone being located in the middle of the length of the cathode block.
During the investigations leading to the present invention, it was found that introduction of a heat sink increases the specific energy consumption, i.e. has an adverse effect on the energy consumption. However, a desired decrease in the specific energy consumption can be achieved when, instead of removing the energy, additional energy is introduced into predetermined regions by adaption of the construction. According to the invention, this is achieved by additiona l inductive heating, with only the middle section of the future cathode being located in the core region of the induction coil. The length of the core of the induction coil can be set by appropriate choice of type and thickness of the packing medium and the thermal conductivity of the body so that the induction power provides part or all of the required heat and the region located outside the zone where the induction coil is effective is heated only by the applied direct current and/or by thermal conduction of the cathode block itself.
A preferred embodiment of the invention is illustrated by the drawing. Fig. 1 shows a side view of a~cathode block.
For reasons of clarity, the figure shows only one cathode block 4 which is heated by the Joule heat generated by the direct current flowing in the circuit 1 in a longi-tudinal graphitization. By means of an AC voltage source and leads 2, an oscillating magnetic field is generated in the coil 3 and induces an AC voltage in the middle zone of the cathode block 4. An electric current governed by the electrical resistance then flows in this zone and effects further heating of the material in this zone.
The length of the zone which is inductively heated is preferably from 25 to 90 0, particularly preferably from to 80 0, of the total length of the cathode block.
It is therefore an object of the present invention to provide a practical process for producing cathodes with an electrical conductivity varying along their length.
This object is achieved according to the invention by an additional inductive heating of the cathode blocks.
The invention accordingly provides a process for produc-ing cathode blocks which can be used for the electrolytic production of aluminum, which comprises carrying out a longitudinal graphitization of carbonized.cathode blocks and effecting the graphitization at least partly by inductive heating of the cathode block, with the inductively heated zone being located in the middle of the length of the cathode block.
During the investigations leading to the present invention, it was found that introduction of a heat sink increases the specific energy consumption, i.e. has an adverse effect on the energy consumption. However, a desired decrease in the specific energy consumption can be achieved when, instead of removing the energy, additional energy is introduced into predetermined regions by adaption of the construction. According to the invention, this is achieved by additiona l inductive heating, with only the middle section of the future cathode being located in the core region of the induction coil. The length of the core of the induction coil can be set by appropriate choice of type and thickness of the packing medium and the thermal conductivity of the body so that the induction power provides part or all of the required heat and the region located outside the zone where the induction coil is effective is heated only by the applied direct current and/or by thermal conduction of the cathode block itself.
A preferred embodiment of the invention is illustrated by the drawing. Fig. 1 shows a side view of a~cathode block.
For reasons of clarity, the figure shows only one cathode block 4 which is heated by the Joule heat generated by the direct current flowing in the circuit 1 in a longi-tudinal graphitization. By means of an AC voltage source and leads 2, an oscillating magnetic field is generated in the coil 3 and induces an AC voltage in the middle zone of the cathode block 4. An electric current governed by the electrical resistance then flows in this zone and effects further heating of the material in this zone.
The length of the zone which is inductively heated is preferably from 25 to 90 0, particularly preferably from to 80 0, of the total length of the cathode block.
Furthermore, the inductive heating preferably contributes at least 10 o and up to 100 0 of the total heat for the cathode block concerned. The heat generated by inductive heating in the middle of the cathode block is at least 10 o more than that at the outer ends of the cathode block.
It is possible and preferred for the inductive heating to be switched on only during the course of the graphitiza-tion process. The direct heating in the longitudinal graphitization process can then be operated at a lower electric power and thus more inexpensively and, in addition, the induction frequency can be made lower and thus cheaper. The induction frequency required is a function of the dimensions of the cathode blocks, its specific electrical resistance and its magnetic susceptibility. The inductive heating is preferably switched on only after 20 0 of the total heating time has lapsed.
The current density in electrolysis cells using the cathodes produced in this way displays a significantly lower deviation from the mean over the length of the cathodes; this deviation is preferably not more than 20 0, particularly preferably not more than 10 o and in particular not more than 5 0.
The graphitized cathode blocks produced by the process of the invention display more uniform corrosion over the length of the cathode and therefore have a significantly increased life compared to the conventional blocks having a homogeneous distribution of the electrical conductivity when used in the production of aluminum by electrolytic reduction of aluminum oxide in a bath of molten cryolite.
It is possible and preferred for the inductive heating to be switched on only during the course of the graphitiza-tion process. The direct heating in the longitudinal graphitization process can then be operated at a lower electric power and thus more inexpensively and, in addition, the induction frequency can be made lower and thus cheaper. The induction frequency required is a function of the dimensions of the cathode blocks, its specific electrical resistance and its magnetic susceptibility. The inductive heating is preferably switched on only after 20 0 of the total heating time has lapsed.
The current density in electrolysis cells using the cathodes produced in this way displays a significantly lower deviation from the mean over the length of the cathodes; this deviation is preferably not more than 20 0, particularly preferably not more than 10 o and in particular not more than 5 0.
The graphitized cathode blocks produced by the process of the invention display more uniform corrosion over the length of the cathode and therefore have a significantly increased life compared to the conventional blocks having a homogeneous distribution of the electrical conductivity when used in the production of aluminum by electrolytic reduction of aluminum oxide in a bath of molten cryolite.
Claims (7)
1. A process for producing cathode blocks which can be used for the electrolytic production of aluminum, which comprises carrying out a longitudinal graphi-tization of carbonized cathode blocks and effecting the graphitization at least partly by inductive heating of the cathode block, with the inductively heated zone being located in the middle of the length of the cathode block.
2. The process as claimed in claim 1, wherein the length of the zone which is inductively heated is from 25 to 90 % of the total length of the cathode block.
3. The process as claimed in claim 1, wherein the length of the zone which is inductively heated is from 35 to 80 % of the total length of the cathode block.
4. The process as claimed in claim 1, wherein the inductive heating contributes at least 10 % and up to 100 % of the total heating power for the cathode block concerned.
5. The process as claimed in claim 1, wherein the inductive heating contributes to a nonuniform profile over the length of the cathode block, with the heat generated in the middle of the cathode block being at least 10 % more than that at the outer ends of the zone which is inductively heated.
6. The process as claimed in claim 1, wherein the inductive heating is switched on only during the course of the graphitization process.
7. The process as claimed in claim 1, wherein the inductive heating is switched on only after 20 % of the total heating time has elapsed.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE10164010.2 | 2001-12-28 | ||
| DE2001164010 DE10164010C1 (en) | 2001-12-28 | 2001-12-28 | Production of cathode blocks, used for the electrolytic recovery of aluminum, comprises graphitizing carbonized cathode blocks in the longitudinal direction by inductively heating the cathode blocks in the center |
| PCT/EP2002/014558 WO2003055824A1 (en) | 2001-12-28 | 2002-12-19 | Method for the production of cathode blocks |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2470644A1 true CA2470644A1 (en) | 2003-07-10 |
Family
ID=7710904
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002470644A Abandoned CA2470644A1 (en) | 2001-12-28 | 2002-12-19 | Process for producing cathode blocks |
Country Status (8)
| Country | Link |
|---|---|
| EP (1) | EP1463692B1 (en) |
| AR (1) | AR037914A1 (en) |
| AU (1) | AU2002367098A1 (en) |
| BR (1) | BR0215326A (en) |
| CA (1) | CA2470644A1 (en) |
| DE (2) | DE10164010C1 (en) |
| PL (1) | PL201671B1 (en) |
| WO (1) | WO2003055824A1 (en) |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4071604A (en) * | 1974-12-03 | 1978-01-31 | Advanced Technology Center, Inc. | Method of producing homogeneous carbon and graphite bodies |
| US4847021A (en) * | 1986-06-26 | 1989-07-11 | Union Carbide Corporation | Process for producing high density carbon and graphite articles |
| FR2789091B1 (en) * | 1999-02-02 | 2001-03-09 | Carbone Savoie | GRAPHITE CATHODE FOR ALUMINUM ELECTROLYSIS |
-
2001
- 2001-12-28 DE DE2001164010 patent/DE10164010C1/en not_active Expired - Fee Related
-
2002
- 2002-12-18 AR ARP020104965 patent/AR037914A1/en unknown
- 2002-12-19 DE DE50206938T patent/DE50206938D1/en not_active Expired - Fee Related
- 2002-12-19 CA CA002470644A patent/CA2470644A1/en not_active Abandoned
- 2002-12-19 PL PL368561A patent/PL201671B1/en not_active IP Right Cessation
- 2002-12-19 BR BR0215326-2A patent/BR0215326A/en active Search and Examination
- 2002-12-19 AU AU2002367098A patent/AU2002367098A1/en not_active Abandoned
- 2002-12-19 EP EP02805766A patent/EP1463692B1/en not_active Expired - Lifetime
- 2002-12-19 WO PCT/EP2002/014558 patent/WO2003055824A1/en active IP Right Grant
Also Published As
| Publication number | Publication date |
|---|---|
| BR0215326A (en) | 2004-10-19 |
| PL201671B1 (en) | 2009-04-30 |
| PL368561A1 (en) | 2005-04-04 |
| EP1463692A1 (en) | 2004-10-06 |
| EP1463692B1 (en) | 2006-05-24 |
| AR037914A1 (en) | 2004-12-22 |
| AU2002367098A1 (en) | 2003-07-15 |
| DE50206938D1 (en) | 2006-06-29 |
| WO2003055824A1 (en) | 2003-07-10 |
| DE10164010C1 (en) | 2003-04-30 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Discontinued |