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EP0047246B1 - Procede et dispositif pour la suppression des perturbations magnetiques dans les cuves d'electrolyse - Google Patents

Procede et dispositif pour la suppression des perturbations magnetiques dans les cuves d'electrolyse Download PDF

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Publication number
EP0047246B1
EP0047246B1 EP80902175A EP80902175A EP0047246B1 EP 0047246 B1 EP0047246 B1 EP 0047246B1 EP 80902175 A EP80902175 A EP 80902175A EP 80902175 A EP80902175 A EP 80902175A EP 0047246 B1 EP0047246 B1 EP 0047246B1
Authority
EP
European Patent Office
Prior art keywords
series
cathodic
tank
current
conductors
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
Application number
EP80902175A
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German (de)
English (en)
French (fr)
Other versions
EP0047246A1 (fr
Inventor
Pierre Homsi
Maurice Keinborg
Bernard Langon
Paul Morel
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.)
Rio Tinto France SAS
Original Assignee
Aluminium Pechiney SA
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 Aluminium Pechiney SA filed Critical Aluminium Pechiney SA
Publication of EP0047246A1 publication Critical patent/EP0047246A1/fr
Application granted granted Critical
Publication of EP0047246B1 publication Critical patent/EP0047246B1/fr
Expired legal-status Critical Current

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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
    • C25C3/16—Electric current supply devices, e.g. bus bars

Definitions

  • the present invention relates to a new device and a new method for eliminating magnetic disturbances harmful to the proper functioning of very high intensity electrolysis cells placed across.
  • These tanks are intended for the production of aluminum by electrolysis of the alumina dissolved in the aluminum and sodium fluoride baths.
  • the invention applies to the reduction of the magnetic forces applied to the liquid metal contained in these tanks. These forces are due to the combined action of the horizontal currents appearing in the metal and the magnetic field created by the conductors of a tank and its neighbors in the same line, as well as by the conductors of the tanks of adjacent lines.
  • the tanks are, in fact, arranged in series according to a certain number of adjacent rows, so as to ensure the return of the current to its source.
  • the invention only applies to the balancing of the magnetic field created by the conductors of the tank and of its neighbors in the same line.
  • the influence of one or more adjacent lines, when these are at a distance relatively close to the line in question, is the subject of separate patents: French patent 2,333,060 and its certificate of addition 2,343,826 and French patent application filed on May 11, 1978 and published under number 2425482.
  • the sides of the tank are called “short sides” and “long sides”, the latter being, in the case of series of tanks across, perpendicular to the axis of the series; the expression “head” is used to designate the ends, on the short sides, of both the tank and the anode system.
  • the direction of the current will go from the bottom to the top of each drawing and will be indicated by an arrow.
  • the object of the invention is a device for the suppression of magnetic disturbances in the series of igneous electrolysis cells intended for the production of aluminum, from alumina dissolved in the molten cryolite, operating at a very high intensity. , being able to reach from 200,000 to 300,000 amperes, said tanks comprising a parallelepipedic box supporting cathode blocks in which the cathode current outputs, called “cathode outputs", are sealed, and an anode system (which may be of the self-cooking Soderberg type, or of the prebaked multiple anode type) - suspended from a spider, the tanks being electrically connected in series by connecting conductors and arranged transversely with respect to the axis Ox of the series, so that the short side of the box and of the anode system are parallel to the axis of the series, the cathode outputs being constituted by a plurality conductive elements sealed in the cathode blocks and emerging vertically from the bottom of the box, device in which
  • Another object of the invention is a method for the suppression of magnetic disturbances in the series of igneous electrolysis cells intended for the production of aluminum from alumina dissolved in the molten cryolite, operating at an intensity of up to 200 000 to 300,000 amperes, said tanks comprising a parallelepipedic box supporting cathode carbon blocks in which the cathode current outputs are sealed, and an anode system suspended from a cross, the tanks being electrically connected in series by conductors connecting the outputs cathodics of a tank at the cross of the next tank, and being arranged transversely with respect to the axis Ox of the series, so that the short side of the box and of the anode system are parallel to the axis of the series , the cathode current being extracted by a plurality of conductive elements sealed in the cathode blocks and exiting vertically through the bottom of the caisso n, method according to which a fraction of the total current of between 30 and 54%, flowing in the connecting conductors
  • the current is extracted from the carbon cathode by vertical outlets (2) which we will designate hereinafter by the term of bottom outlets.
  • vertical outlets (2) which we will designate hereinafter by the term of bottom outlets.
  • This process makes it possible to considerably reduce the horizontal currents in the metal while obtaining a gain of the order of 0.1 V on the. cathodic fall.
  • This improvement in cathodic drop results in a reduction of 300 kMh / t in the specific energy consumed by the tank.
  • bottom exits has been described in several old patents; three of them only use bottom outlets, excluding any description of the connecting conductors: FR 953 374, IT 451 183 and FR 1,125,949.
  • the first relates only to tanks with relatively low intensity, close to 100,000 A.
  • the paths of the connecting conductors are long, leading to a significant investment in conductors and drops high line voltage.
  • the invention makes it possible to eliminate magnetic disturbances on these tanks by eliminating horizontal currents and by balancing the magnetic field.
  • the components Bx and Bz are, by construction, asymmetrical with respect to the plane x o z.
  • the invention consists, for tanks across an intensity between 200,000 A and 300,000 A, in a combination of the outputs from the bottom and a bypass of part of the current in conductors arranged outside the two vertical planes passing through the ends of the anode system.
  • the branch conductors are therefore placed in the hatched area ABCDEF of FIG. 4.
  • This area is delimited on the box side, by the vertical walls AB on the short side of the box, and, below the box, by the bottom up to 'plumb with the end of the anode system (BC).
  • BC anode system
  • the conductor will be slightly moved away from the wall of the box, at a distance compatible with the requirements of electrical safety.
  • On the side opposite to the wall of the box there is no theoretical limit of the area.
  • we will not deviate beyond an EF plane located about one meter from the wall of the box.
  • the height of the zone is theoretically unlimited, but, for reasons of economy of journey and so that the bypass conductor does not interfere with operations on the tank, the height of the zone will be delimited, in its upper part, by the top of the box (FA) and, in its lower part, by a border ED located about one meter below the bottom of the box.
  • Figures 5, 6 and 7 provide a better definition of the term "branch conductor”.
  • the cathodic current collected under the tank considered circulates in the conductor (10) and is derived by the heads of the tank considered (outside the vertical plane passing through the end of the anode system (4) by the bypass conductor (11) which bypasses the two upstream and downstream angles of the end (12) of the anode plane).
  • the bypass conductor (11) passes under the box (3) of the tank in question and is connected to the crosspiece of the next tank by the rise (13).
  • the cathodic current collected under the tank in question circulates in the conductor (14) and is derived by the heads of the next tank by the bypass conductor (15) which bypasses the two angles upstream and downstream of the end (12) of the anodic plane of the next tank (outside the vertical plane passing through the end of said anodic system).
  • the bypass conductor (15) runs along its side of the next tank on its short side.
  • part of the cathode current collected under the tank in question circulates in the conductor (16) and is derived by the heads of the tank considered by the bypass conductor (17) which bypasses the two angles upstream and downstream of the end (12) of the anode plane of the tank considered.
  • the bypass conductor (17) runs along the box (3) of the tank considered on its short side.
  • Another part of the cathode current, collected under the tank in question circulates in the conductor (18) and is derived by the heads of the next tank by the same conductor.
  • bypass (19) which bypasses the two upstream and downstream angles of the end (12) of the anode plane of the next tank.
  • the bypass conductor (19) runs along the box (3) of the next tank on its short side.
  • the number of positive rises will generally be greater than or equal to four. However, in the case where the invention is applied to tanks with an intensity of less than 200,000 A, it will be possible to settle for less than four positive rises.
  • This circuit although having the advantage of the shortest electrical path, does not allow the magnetic field of a tank with outlets from the bottom to be balanced.
  • FIGS. 9 and 13 we only very schematically represent the conductors connecting the cathode outputs (2) of the tank in question to the spider (9) supplying the anodes of the next tank.
  • the connecting conductors pass below the level of the work surface, and then join the cross braces by vertical or slightly oblique climbs.
  • each cathode block arranged parallel to the axis Ox has three vertical outlets. But, well heard, the actual number of outputs can be different without departing from the scope of the invention.
  • the current drawn at the two ends of the cathode is derived by the heads of the next tank to feed its cross-bar downstream by two positive rises located at 1/4 and 3/4.
  • the fraction of current flowing through each of the two branch conductors is 3/16, or 18.75%, of the total current.
  • the rest of the current feeds the spider of the next tank upstream, in three positive ascents, one located along the axis Ox of the tank and the other two at the heads of the spider.
  • the latter climbs can be placed either on the large or on the small side of the tank.
  • the maximum horizontal field Bx is 60.1 0 - 4.
  • the current drawn at the two ends of the cathode is collected on either side of the tank considered in the inter-tank space. Part of this current is derived from the heads of the tank in question.
  • the bypass conductor then goes along the heads of the next tank and feeds its spider, downstream at 1/4 and 3/4 of the long side. Each of the bypass conductors by the heads of the next tank is crossed by 1/5 of the total current.
  • the rest of the cathode current feeds upstream the cross of the next tank by four positive ascents located at 1/8, 3/8, 5/8 and 7/8.
  • the maximum horizontal field Bx is 25.10- 4 T.
  • the current drawn at 1/4 and 3/4 of the cathode joins along the large upstream side of the tank considered the bypass conductor circulating on the heads of the tank considered before supplying upstream the heads of the spider of the next tank by a positive rise on both sides of the tank.
  • the climbs can be indifferently placed on the long side or on the short side of the tank.
  • Each of the bypass conductors through the heads of the tank in question is traversed by 3/16, or 18.75%, of the total intensity.
  • the rest of the cathode current feeds directly upstream, as shown in Figure 11, the cross of the next tank by three positive rises located 1/4, 1/2 and 3/4 of the large. side.
  • the average vertical field per quadrant of this tank at 250,000 A, and taking into account the effect of the ferromagnetic parts is:
  • the maximum horizontal field Bx is 40.10- 4 T.
  • the current drawn at the two ends of the cathode joins along the large upstream side of the tank considered the bypass conductor circulating on the heads of the tank considered before supplying the upstream end of the crosspiece of the next tank by a positive rise on either side of the tank.
  • the climbs can be placed either on the long side or on the short side.
  • Each of the bypass conductors by the heads of the tank in question is traversed by 1/4 of the total intensity.
  • the rest of the cathode current feeds directly upstream the cross of the next tank by three positive rises located at 1/4, 1/2 and 3/4 of the long side.
  • the maximum horizontal field Bx is 48.10- 4 T.
  • This collector supplies the bypass conductor through the heads of the tank in question.
  • the bypass current then feeds the upstream crosspiece of the next tank by two positive ascents located 1/8 and 7/8 of the long side.
  • Each of the bypass conductors by the heads of the tank in question is traversed by 1/4 of the total intensity.
  • the rest of the cathode current feeds upstream the cross of the next tank by two positive ascents located 3/8 and 5/8 of the long side.
  • the maximum horizontal field Bx is 22.10- 4 T.
  • Figure 14 schematically gives the arrangement of all the connecting conductors between the tank considered and the next tank.
  • Figure 15 is a cross section along an axis parallel to Ox of the tank considered and the next tank. The numbering of the elements is common to the two figures.
  • the alumina supply device, the superstructure, the anodes and their suspension system have either been omitted, or shown very schematically for clarity of the drawing. They are, in reality, in accordance with the prior art.
  • the cathodic outputs through the bottoms (20) are connected to several negative collectors (21).
  • the current collected at the two ends of the cathode is connected by the conductors (22) to the bypass conductors (8) by the heads of the next tank and then feeds the crosspiece (9) of this tank by the risers (23) located ' on the downstream side at 1/4 and 3/4.
  • Each of the bypass conductors through the heads is crossed by 3/16, or 18.75%, of the total intensity.
  • the Oz dimension of these conductors is determined so as to ensure the balance of the magnetic field.
  • the location area of these conductors was previously defined ( Figure 4).
  • the current collected at the center of the cathode is connected by the conductors (24) to three vertical risers, connected to the heads and in the middle of the spider, on the upstream side.
  • Each of the conductors supplying the heads of the cross is crossed by 1/4 of the total intensity and the conductor feeding the center of the cross is crossed by 1/8 of the total intensity.
  • the tanks of the series built according to the invention have the following characteristics: inner dimension 13.68x4.15 (in meters) of the box
  • the corresponding specific energy consumption is 12,690 kMh / tonne AI, which is a record value with tanks operating at such a high intensity. This gain was obtained inter alia by a lowering of the cathodic drop which was on average at 0.25 V.

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  • 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)
EP80902175A 1979-11-07 1980-11-04 Procede et dispositif pour la suppression des perturbations magnetiques dans les cuves d'electrolyse Expired EP0047246B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR7928132A FR2469475A1 (fr) 1979-11-07 1979-11-07 Procede et dispositif pour la suppression des perturbations magnetiques dans les cuves d'electrolyse a tres haute intensite placees en travers
FR7928132 1979-11-07

Publications (2)

Publication Number Publication Date
EP0047246A1 EP0047246A1 (fr) 1982-03-17
EP0047246B1 true EP0047246B1 (fr) 1985-01-23

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ID=9231687

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EP80902175A Expired EP0047246B1 (fr) 1979-11-07 1980-11-04 Procede et dispositif pour la suppression des perturbations magnetiques dans les cuves d'electrolyse

Country Status (18)

Country Link
EP (1) EP0047246B1 (pt)
JP (1) JPS56501247A (pt)
KR (1) KR850001537B1 (pt)
BR (1) BR8008907A (pt)
CA (1) CA1143695A (pt)
DE (1) DE3070034D1 (pt)
ES (1) ES496595A0 (pt)
FR (1) FR2469475A1 (pt)
GR (1) GR70348B (pt)
HU (1) HU191178B (pt)
IN (1) IN152568B (pt)
MX (1) MX154537A (pt)
NZ (1) NZ195424A (pt)
OA (1) OA08223A (pt)
PL (1) PL132150B1 (pt)
RO (1) RO82538B (pt)
WO (1) WO1981001299A1 (pt)
YU (1) YU42988B (pt)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU2008233392B2 (en) * 2007-04-02 2012-04-26 Norsk Hydro Asa Improvements relating to electrolysis cells connected in series and a method for operation of same
CN105452536A (zh) * 2013-08-09 2016-03-30 力拓艾尔坎国际有限公司 包括补偿电路的铝厂

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH648605A5 (de) * 1980-06-23 1985-03-29 Alusuisse Schienenanordnung einer elektrolysezelle.
FR2505368B1 (fr) * 1981-05-05 1985-09-27 Pechiney Aluminium Dispositif pour la production d'aluminium par electrolyse ignee sous tres haute densite
FR2552782B1 (fr) * 1983-10-04 1989-08-18 Pechiney Aluminium Cuve d'electrolyse a intensite superieure a 250 000 amperes pour la production d'aluminium par le procede hall-heroult
FR2583068B1 (fr) * 1985-06-05 1987-09-11 Pechiney Aluminium Circuit de connexion electrique de series de cuves d'electrolyse pour la production d'aluminium sous tres haute intensite
AUPO053496A0 (en) * 1996-06-18 1996-07-11 Comalco Aluminium Limited Cathode construction
AU713342B2 (en) * 1996-06-18 1999-12-02 Comalco Aluminium Limited Cathode construction
FR2977898A1 (fr) 2011-07-12 2013-01-18 Rio Tinto Alcan Int Ltd Aluminerie comprenant des cuves a sortie cathodique par le fond du caisson et des moyens de stabilisation des cuves
TR201807790T4 (tr) 2011-07-12 2018-06-21 Rio Tinto Alcan Int Ltd Süper iletken bir malzemeden yapılma elektrik iletkenlerini içeren alüminyum izabe fırını.
MY183698A (en) 2015-02-09 2021-03-08 Rio Tinto Alcan Int Ltd Aluminium smelter and method to compensate for a magnetic field created by the circulation of the electrolysis current of said aluminium smelter

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1187809B (de) * 1963-11-22 1965-02-25 Vaw Ver Aluminium Werke Ag Elektrolysezelle zur schmelzflusselektrolytischen Herstellung von Aluminium
US3640800A (en) * 1970-07-14 1972-02-08 Arthur F Johnson Electrolytic cell
GB2008617B (en) * 1977-11-23 1982-03-31 Alcan Res & Dev Electrolytic reduction cells
US4194959A (en) * 1977-11-23 1980-03-25 Alcan Research And Development Limited Electrolytic reduction cells
SU863719A1 (ru) * 1978-02-06 1981-09-15 Всесоюзный Научно-Исследовательский И Проектный Институт Алюминиевой,Магниевой И Электродной Промышленности Ошиновка электролизеров дл получени алюмини

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU2008233392B2 (en) * 2007-04-02 2012-04-26 Norsk Hydro Asa Improvements relating to electrolysis cells connected in series and a method for operation of same
CN105452536A (zh) * 2013-08-09 2016-03-30 力拓艾尔坎国际有限公司 包括补偿电路的铝厂
CN105452536B (zh) * 2013-08-09 2017-09-19 力拓艾尔坎国际有限公司 包括补偿电路的铝厂

Also Published As

Publication number Publication date
EP0047246A1 (fr) 1982-03-17
HU191178B (en) 1987-01-28
DE3070034D1 (en) 1985-03-07
YU280380A (en) 1984-02-29
PL132150B1 (en) 1985-02-28
OA08223A (fr) 1987-10-30
FR2469475A1 (fr) 1981-05-22
NZ195424A (en) 1984-12-14
FR2469475B1 (pt) 1982-12-17
RO82538A (ro) 1984-02-21
IN152568B (pt) 1984-02-11
YU42988B (en) 1989-02-28
MX154537A (es) 1987-09-28
CA1143695A (fr) 1983-03-29
JPS56501247A (pt) 1981-09-03
ES8200410A1 (es) 1981-10-16
WO1981001299A1 (fr) 1981-05-14
BR8008907A (pt) 1981-08-25
KR830004457A (ko) 1983-07-13
RO82538B (ro) 1984-02-28
GR70348B (pt) 1982-09-23
ES496595A0 (es) 1981-10-16
PL227652A1 (pt) 1981-08-21
KR850001537B1 (ko) 1985-10-16

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