EP1151150B1 - Cathode graphite pour l'electrolyse de l'aluminium - Google Patents

Cathode graphite pour l'electrolyse de l'aluminium Download PDF

Info

Publication number
EP1151150B1
EP1151150B1 EP00901691A EP00901691A EP1151150B1 EP 1151150 B1 EP1151150 B1 EP 1151150B1 EP 00901691 A EP00901691 A EP 00901691A EP 00901691 A EP00901691 A EP 00901691A EP 1151150 B1 EP1151150 B1 EP 1151150B1
Authority
EP
European Patent Office
Prior art keywords
cathode
end regions
cathodes
central region
graphite
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.)
Expired - Lifetime
Application number
EP00901691A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP1151150A1 (fr
Inventor
Jean-Michel Dreyfus
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Carbone Savoie SAS
Original Assignee
Carbone Savoie SAS
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Carbone Savoie SAS filed Critical Carbone Savoie SAS
Publication of EP1151150A1 publication Critical patent/EP1151150A1/fr
Application granted granted Critical
Publication of EP1151150B1 publication Critical patent/EP1151150B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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

Definitions

  • the present invention relates to a graphite cathode for aluminum electrolysis.
  • an electrolytic cell In the electrolytic process used in most factories aluminum production, an electrolytic cell includes, in a box metallic sheathed with refractories, a cathode sole composed of several cathode blocks juxtaposed. This set constitutes the crucible which, rendered sealed by pot lining, is the seat of transformation, under the action of electric current, of the aluminum electrolytic bath. This reaction takes place at a temperature generally above 950 ° C.
  • the graphitization treatment of the graphite cathode increases the electrical and thermal conductivities, thus creating sufficient conditions for optimized operation of a electrolysis tank.
  • Energy consumption decreases due to decline the electrical resistance of the cathode.
  • Another way to take advantage of this decrease in electrical resistance consists in increasing the intensity of the current injected into the tank, allowing an increase in production aluminum.
  • the high value of thermal conductivity of the cathode allows the evacuation of the excess heat generated by the increase intensity.
  • graphite cathode vessels appear less electrically unstable, i.e. with less fluctuation in electrical potentials, than carbon cathode tanks.
  • the single figure of the attached schematic drawing shows a block cathode 3, with the cathode bars of current supply 2, the initial profile is designated by the reference 4.
  • the erosion profile 5, represented in dotted, shows that this erosion is accentuated at the ends of the block cathode.
  • Document FR 2 117 960 describes a cathode for the preparation aluminum by electrolysis.
  • This cathode is made from several semi-graphitic carbon blocks, with different resistivities each other.
  • This complex structure due to the juxtaposition of blocks with the electrical discontinuity which it involves, is justified not by a reduced erosion, since cathodes of this type are not sensitive erosion, but by a decrease in the swelling of the sole in the area Central.
  • the document FR 2 351 192 describes, in a device for production of aluminum, a cathode assembly comprising a bar cathodic and a carbon block separated by a heterogeneous interface allowing to vary over the length of the cathode assembly, the contact resistance between the cathode bar and the carbon block.
  • the erosion rate of a graphite cathode block is, by Consequently, its weak point, and its economic attractiveness in terms of gain of production may disappear if the service life cannot be increased.
  • the problem is therefore to reduce erosion of cathodes by graphite, in particular in the end zones thereof.
  • the object of the invention is to provide a graphite cathode whose service life is increased by limiting the erosion that occurs at ends.
  • the cathode in graphite is in one piece and its electrical resistivity is heterogeneous along its longitudinal axis, this resistivity being higher in the zones cathode end than in the central area of the cathode, the difference resistivity in the end zones and in the central zone of the cathode being obtained by a different heat treatment in these different zones during the graphitization operation, the end zones being at one temperature lower than that of the central zone.
  • the average resistivity of the product will remain compatible with a optimized operation of the electrolysis tank.
  • the highest resistivity in the cathode end zones channels the current lines to the center of the tank. Because of this, the high current densities usually recorded to the output of the cathode bars are attenuated, inhibiting thus the erosion mechanism in these areas. The life of the tank is therefore increased.
  • the cathode end areas can be considered as located between approximately 0 and 800 mm from each end.
  • the cathode end zones are brought to a temperature of the order from 2,200-2,500 ° C, while the central zone is brought to a temperature of the order of 2,700 to 3,000 ° C.
  • the difference of heat treatment in the end zones and in the central zone of the cathode is obtained by limiting the thermal insulation of the graphitization furnace and / or by having thermal drains in the end zones of the cathodes, to increase heat losses.
  • the difference in treatment thermal in the end zones and in the central zone of the cathode is obtained by creating, during the graphitization operation, modifications local current lines and, therefore, the resulting Joule effect.
  • the difference of heat treatment between the end zones and the central zone is obtained by modulating the resistivity of the resistor grain between two cathodes and / or by having thermal drains in the end zones.
  • FIGS 2 to 4 show an Acheson type oven 6, in which a number of cathodes 3 are arranged parallel to each other others, in several rows, with interposition between the different cathodes of a resistor grain 7.
  • This resistor grain can be constituted, for example by carbon or coke granules.
  • the assembly is arranged inside a heat-insulating grain 8. Electric energy is injected inside the oven, to perform the graphitization operation, the heating resulting from the effect Joule.
  • the streamlines are perpendicular to the axis of the cathodes 3.
  • the resistivity of the resistor grain is higher in the zones 9 corresponding to the end zones of the cathodes 3, that that of this grain resistor in zone 10 corresponding to the central part cathodes. It is also possible to reduce the thickness of the grain insulation 8 in the end areas of the cathodes, to promote the phenomenon of limitation of the graphitization temperature in these areas end by heat loss.
  • FIG. 5 represents a longitudinal oven 11 in which several cathodes 3 are arranged end to end, with interposition between two cathodes adjacent to a graphitization joint 12.
  • the graphitization joints are as weak as possible to avoid unwanted heating at the junction between the cathodes.
  • heat losses materialized by arrows are created in the end zones of the cathodes, by providing a smaller thickness of insulation 8, and / or the presence of thermal drains which can be made of graphite and positioned perpendicular to the cathodes, facing the areas to be cooled.
  • the invention provides a great improvement to the existing technique by providing a cathode of traditional structure, and obtained by known means, having a higher resistivity in its end zones than in its central zone, thus reducing the current density in the cathode at its ends, and increase resistance to erosion in these areas end.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electrolytic Production Of Metals (AREA)
  • Electrodes For Compound Or Non-Metal Manufacture (AREA)
EP00901691A 1999-02-02 2000-02-01 Cathode graphite pour l'electrolyse de l'aluminium Expired - Lifetime EP1151150B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR9901320A FR2789091B1 (fr) 1999-02-02 1999-02-02 Cathode graphite pour l'electrolyse de l'aluminium
FR9901320 1999-02-02
PCT/FR2000/000232 WO2000046426A1 (fr) 1999-02-02 2000-02-01 Cathode graphite pour l'electrolyse de l'aluminium

Publications (2)

Publication Number Publication Date
EP1151150A1 EP1151150A1 (fr) 2001-11-07
EP1151150B1 true EP1151150B1 (fr) 2004-05-19

Family

ID=9541620

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00901691A Expired - Lifetime EP1151150B1 (fr) 1999-02-02 2000-02-01 Cathode graphite pour l'electrolyse de l'aluminium

Country Status (18)

Country Link
US (1) US6627062B1 (no)
EP (1) EP1151150B1 (no)
JP (1) JP2002538293A (no)
CN (1) CN1272471C (no)
AT (1) ATE267277T1 (no)
AU (1) AU776902B2 (no)
BR (1) BR0007917A (no)
CA (1) CA2361610C (no)
DE (1) DE60010861T2 (no)
ES (1) ES2218108T3 (no)
FR (1) FR2789091B1 (no)
IS (1) IS2480B (no)
MX (1) MXPA01007830A (no)
NO (1) NO20013775L (no)
PL (1) PL195085B1 (no)
RU (1) RU2245395C2 (no)
WO (1) WO2000046426A1 (no)
ZA (1) ZA200106312B (no)

Families Citing this family (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10164010C1 (de) * 2001-12-28 2003-04-30 Sgl Carbon Ag Verfahren zur Herstellung von Kathodenblöcken
DE10164013C1 (de) * 2001-12-28 2003-04-03 Sgl Carbon Ag Verfahren zum Graphitieren von Kathodenblöcken
DE10164009B4 (de) * 2001-12-28 2005-04-07 Sgl Carbon Ag Verfahren zur Herstellung von Kathodenblöcken
DE10164008C1 (de) * 2001-12-28 2003-04-30 Sgl Carbon Ag Graphitierte Kathodenblöcke
DE10164011C1 (de) * 2001-12-28 2003-05-08 Sgl Carbon Ag Verfahren zum Graphitieren von Kathodenblöcken
DE10164014C1 (de) * 2001-12-28 2003-05-22 Sgl Carbon Ag Verfahren zum Graphitieren von Kathodenblöcken
DE10164012C1 (de) * 2001-12-28 2003-04-30 Sgl Carbon Ag Verfahren zur kontinuierlichen Graphitierung
DE10261745B3 (de) * 2002-12-30 2004-07-22 Sgl Carbon Ag Kathodensystem zur elektrolytischen Aluminiumgewinnung
FR2861090B1 (fr) * 2003-10-17 2005-12-23 Sgl Carbone Ag Cathode pour l'electrolyse de l'aluminium, son procede de fabrication et utilisation de celle-ci
RU2443623C1 (ru) * 2010-10-14 2012-02-27 Закрытое акционерное общество "Институт новых углеродных материалов и технологий" (ЗАО "ИНУМиТ") Способ получения графитированного материала с повышенной абразивной стойкостью
CN102234820B (zh) * 2011-08-04 2013-03-20 中国铝业股份有限公司 一种减少铝电解槽铝液水平电流的方法
NO2650404T3 (no) * 2012-04-12 2018-06-09
CN110184627B (zh) * 2019-05-10 2020-11-06 中国铝业股份有限公司 一种铝电解用定向导磁阴极钢棒

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1029122A (en) 1910-02-10 1912-06-11 Electrode Company Of America Graphitizing electrodes.
CA968744A (en) * 1970-12-12 1975-06-03 Kurt Lauer Cathode for the winning of aluminum
DE2105247C3 (de) 1971-02-04 1980-06-12 Schweizerische Aluminium Ag, Zuerich (Schweiz) Ofen für die Schmelzflußelektrolyse von Aluminium
CH620948A5 (no) * 1976-05-13 1980-12-31 Alusuisse
DE3327230A1 (de) 1983-07-28 1985-02-07 Sigri Elektrographit Gmbh, 8901 Meitingen Auskleidung fuer elektrolysewanne zur herstellung von aluminium

Also Published As

Publication number Publication date
DE60010861D1 (de) 2004-06-24
JP2002538293A (ja) 2002-11-12
MXPA01007830A (es) 2003-06-04
CN1272471C (zh) 2006-08-30
NO20013775D0 (no) 2001-08-01
RU2245395C2 (ru) 2005-01-27
WO2000046426A1 (fr) 2000-08-10
BR0007917A (pt) 2001-11-27
IS2480B (is) 2008-12-15
US6627062B1 (en) 2003-09-30
CN1342219A (zh) 2002-03-27
FR2789091B1 (fr) 2001-03-09
PL350236A1 (en) 2002-11-18
CA2361610A1 (fr) 2000-08-10
FR2789091A1 (fr) 2000-08-04
ZA200106312B (en) 2003-02-26
AU2301200A (en) 2000-08-25
DE60010861T2 (de) 2004-11-04
CA2361610C (fr) 2004-07-06
ES2218108T3 (es) 2004-11-16
AU776902B2 (en) 2004-09-23
IS6026A (is) 2001-07-27
PL195085B1 (pl) 2007-08-31
EP1151150A1 (fr) 2001-11-07
ATE267277T1 (de) 2004-06-15
NO20013775L (no) 2001-09-28

Similar Documents

Publication Publication Date Title
EP1151150B1 (fr) Cathode graphite pour l'electrolyse de l'aluminium
EP1733075B1 (fr) Element cathodique pour l'equipement d'une cellule d'electrolyse destinee a la production d'aluminium
NO343882B1 (no) Katoder for aluminiumelektrolysecelle med ekspandert grafittfôring
EP1159469B1 (fr) Cathode graphite impregnee pour l'electrolyse de l'aluminium
EP0167461B1 (fr) Anode carbonée à rondins partiellement rétrécis destinée aux cuves pour la production d'aluminium par électrolyse
EP0169152B1 (fr) Bloc cathodique modulaire et cathode à faible chute de tension pour cuves d'électrolyse hall-héroult
CA2496683C (fr) Procede de prechauffage d'une cuve pour la production d'aluminium par electrolyse
WO2000046428A1 (fr) Cathode graphite pour l'electrolyse de l'aluminium
CA1228834A (fr) Ecran sous-cathodique comportant des zones deformables pour les cuves d'electrolyse hall- heroult
FR2576920A1 (fr) Cuve d'electrolyse hall-heroult a barres cathodiques et a calorifugeage dissymetriques
FR2552549A1 (fr) Sonde pour la mesure de la concentration en alumine dans un bain d'electrolyte
CA3122500A1 (fr) Ensemble anodique et cuve d'electrolyse comprenant cet ensemble anodique
CA2539697C (fr) Dispositif et procede de raccordement d'anodes inertes destinees a la production d'aluminium par electrolyse ignee
FR2925531A1 (fr) Dispositif de support pour electrodes dans une installation d'electrolyses
BE563730A (fr) Anode à auto-reconstitution pour fours à cellules multiples destinés à la fabrication électrolytique de l'aluminium, et procédé de fabrication électrolytique de l'aluminium
FR3121938A1 (fr) Multipode et ensemble anodique
FR2861090A1 (fr) Cathode pour l'electrolyse de l'aluminium, son procede de fabrication et utilisation de celle-ci
WO2002068723A1 (fr) Cathode graphite pour l'electrolyse de l'aluminium
WO2012172196A1 (fr) Cuve d'électrolyse destinée à être utilisée pour produire de l'aluminium
CA2470757A1 (en) Process for the graphitization of cathode blocks
CH396423A (fr) Cuve électrolytique pour la production d'aluminium

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17P Request for examination filed

Effective date: 20011004

R17P Request for examination filed (corrected)

Effective date: 20010814

17Q First examination report despatched

Effective date: 20020705

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT DE ES GB IT

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 20040519

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

Free format text: FRENCH

REF Corresponds to:

Ref document number: 60010861

Country of ref document: DE

Date of ref document: 20040624

Kind code of ref document: P

LTIE Lt: invalidation of european patent or patent extension

Effective date: 20040519

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2218108

Country of ref document: ES

Kind code of ref document: T3

REG Reference to a national code

Ref country code: IE

Ref legal event code: FD4D

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20050222

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20140227

Year of fee payment: 15

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20140226

Year of fee payment: 15

Ref country code: AT

Payment date: 20140121

Year of fee payment: 15

Ref country code: IT

Payment date: 20140226

Year of fee payment: 15

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20140227

Year of fee payment: 15

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 60010861

Country of ref document: DE

REG Reference to a national code

Ref country code: AT

Ref legal event code: MM01

Ref document number: 267277

Country of ref document: AT

Kind code of ref document: T

Effective date: 20150201

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20150201

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: AT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20150201

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20150201

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20150901

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20150201

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20160331

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20150202