EP0047246A1 - 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.Info
- Publication number
- EP0047246A1 EP0047246A1 EP80902175A EP80902175A EP0047246A1 EP 0047246 A1 EP0047246 A1 EP 0047246A1 EP 80902175 A EP80902175 A EP 80902175A EP 80902175 A EP80902175 A EP 80902175A EP 0047246 A1 EP0047246 A1 EP 0047246A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- tank
- series
- cathode
- 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.)
- Granted
Links
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
- C25C3/16—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 baths of aluminum and sodium fluorides.
- 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 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 queues, when these are at a distance relatively close to the queue considered, is the subject of separate patents: French patent 2,333,060 and its certificate of addition 2,343,826 and French patent application 2071 filed on May 11, 1978 under No. 78 14676.
- 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.
- tank considered the one from which we extract the current through the cathode
- previous tank that which supplies, from its cathode outputs, the anode system of the tank in question
- nonext tank that whose anode spider is supplied with current from the cathode outputs of the tank considered.
- 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 cry ⁇ lithe, operating at an intensity of up to 200 000 to 300,000 amperes, said tanks comprising a parallelepipedic box supporting cathode blocks in which the cathode current outputs are sealed (called "cathode outputs"), and an anode system (which can be of the Soderberg type for self-cooking, or of the type for multiple anodes precooked) - suspended from a cross, the tanks being electrically connected in series by the conductors connecting the cathode outputs of a given tank to the cross of the next tank in the series, the tanks being, moreover, arranged across by relative to the axis of the series, device in which the cathode outputs consist of a plurality of elements conductive elements, most often metallic, emerging vertically from the bottom of the box, and in which, in addition, part of the connecting
- 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 molten cryolite, operating at an intensity up to 200,000 to 300,000 amperes, said tanks comprising a parallelepipedic box supporting carbon cathode blocks in which the cathode current outputs are sealed and an anode system suspended from a spider, 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 crosswise with respect to the axis of the series, process in which the cathode current is extracted by a plurality of conductive elements sealed in the cathode blocks and exiting vertically through the bottom of the box and in which a fraction of the total current flowing in the connecting conductors between the tanks, fraction between 30 and 54%, is derived in conductors arranged, on at least part of their path, outside the two vertical planes passing through the ends of the
- This derivative current may be symmetrical with respect to the axis of the series, and may also be distributed on each side of the tanks, or be asymmetrical, and be distributed unevenly on each side of the tanks.
- the spider of a tank considered is supplied with current from the cathode outputs of the previous tank by a plurality of vertical risers which can be connected either entirely on the upstream side of said spider, or both on the upstream side and on the downstream side a part of the current which can, moreover, be brought to one and / or the other of the heads of said spider.
- FIG. 1 shows the two cathode outlet systems drawn, for simplicity, on the same tank: lateral outlets and outlets from the bottom.
- FIG. 2 schematically represents the section of a tank, on which the three axes of coordinates used to define the direction of the components of the magnetic field appear.
- FIG. 3 represents the distribution of the average of the vertical component Bz of the magnetic field over the four quadrants of the tank.
- Figure 4 shows schematically the position of the connecting conductors, according to the invention, relative to the vertical plane zz 'passing through the end of the anode system.
- FIGS 5, 6, 7 show, schematically, the various variants of the paths that can be followed by the connecting conductors, in the part of the invention.
- FIG. 8 indicates how the connections between tanks would be made up, using the knowledge of the prior art.
- FIGS 9 to 13 show the implementation of the invention in five different variants, each of which is the subject of an example of implementation.
- Figure 14 is a diagram of a practical embodiment and Figure 15, a section along the axis of the series, of the same embodiment, indicating the actual position of the conductors.
- the current is extracted from the carbon cathode by vertical outlets (2) which we will designate in the rest of the description 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 drop.
- This improvement in cathodic drop results in a reduction of 300 kMh / t in the specific energy consumed by the tank.
- 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 point values of Bz should be low.
- the field will be calculated taking into account the effect of the ferromagnetic parts of the tank and its environment. - A secondary criterion consisting in the reduction of the maximum value of the horizontal component Bx. The maximum value will generally be located at the end of the anode plane, on the short sides of the tank.
- the invention consists, for cross tanks, of an intensity between 200,000 A and 300,000 A, by a combination of the bottom outlets and a branch 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 wall AB on the short side of the box, and, below the box, by the bottom up '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 the wall of the box there is no theoretical limit of the area.
- 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 an ED border 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 considered tank and is connected to the cross of the next tank by the rise (13).
- the cathodic current collected under the tank considered 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 the side of the next tank on its short side.
- part of the cathodic current collected under the tank considered circulates in the conductor (16) and is derived by the heads of the tank considered by the bypass conductor (17) which bypasses the two upstream and downstream angles 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 considered circulates in the conductor (18 and is derived by the heads of the next tank by the same bypass conductor (19) which bypasses the two angles upstream and downstream of the end mite (12) of the anodic plane of the next tank
- the bypass conductor (19) runs along the box (3) of the next tank on its short side.
- the part of the current which is derived by each of the heads of the tank is between 15% and 27% of the total current of the tank. More precisely :
- 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.
- 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 braces by vertical or slightly oblique climbs.
- each cathode block arranged parallel to the axis Ox has three vertical outlets. But, of course, 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 bypass conductors is 3/16, or 18.75%, of the total current.
- the rest of the current feeds the brace 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 brace.
- 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. 10 -4 .
- EXAMPLE 2 Tanks with outlet from the bottom, with six positive ascents, the current derived by the heads of the next tank is collected in the inter-tank space and is sent downstream of the cross of the next tank ( Figure 10) 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 on 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 3/5 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 taken 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 placed either on the long side or on the short side of the tank.
- Each of the bypass conductors through the heads of the tank der ⁇ e is covered 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 long side.
- the maximum horizontal field Bx is 40.10 -4 T.
- EXAMPLE 4 Tank with outlet from the bottom, with five positive ascents, the current derived by the heads of the cuvée in question is taken at both ends of the cathode ( Figure 12)
- the current taken at the two ends of the cathode joins along from 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 spider 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 ascents located 1/4, 1/2 and 3/4 of the long side.
- the maximum horizontal field Bx is 48.10 -4 T.
- EXAMPLE 5 Tank with outputs from the bottom, with four positive ascents, the current derived by the heads of the tank considered is collected in the inter-tank space upstream of the tank considered ( Figure 13)
- This collector supplies the bypass conductor by 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
- the inten- operating site was set at 250,000 A.
- 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 support 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 heads bypass conductors 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 conducers (24) to three vertical ascents, 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: anode surface: 348,000 cm2 interior dimension of the box: 13, 68 x 4, 15
- the invention applies more particularly to series of electrolytic cells operating at intensities between 200 and 300,000 amperes, it can also be applied to series of cells operating at lower intensities included, for example, between 100,000 and 200,000 amps.
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)
Abstract
Description
Claims
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 true EP0047246A1 (fr) | 1982-03-17 |
EP0047246B1 EP0047246B1 (fr) | 1985-01-23 |
Family
ID=9231687
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
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 (fr) |
JP (1) | JPS56501247A (fr) |
KR (1) | KR850001537B1 (fr) |
BR (1) | BR8008907A (fr) |
CA (1) | CA1143695A (fr) |
DE (1) | DE3070034D1 (fr) |
ES (1) | ES8200410A1 (fr) |
FR (1) | FR2469475A1 (fr) |
GR (1) | GR70348B (fr) |
HU (1) | HU191178B (fr) |
IN (1) | IN152568B (fr) |
MX (1) | MX154537A (fr) |
NZ (1) | NZ195424A (fr) |
OA (1) | OA08223A (fr) |
PL (1) | PL132150B1 (fr) |
RO (1) | RO82538B (fr) |
WO (1) | WO1981001299A1 (fr) |
YU (1) | YU42988B (fr) |
Families Citing this family (11)
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 |
AU713342B2 (en) * | 1996-06-18 | 1999-12-02 | Comalco Aluminium Limited | Cathode construction |
AUPO053496A0 (en) * | 1996-06-18 | 1996-07-11 | Comalco Aluminium Limited | Cathode construction |
NO331318B1 (no) * | 2007-04-02 | 2011-11-21 | Norsk Hydro As | Fremgangsmate for drift av elektrolyseceller koblet i serie samt samleskinnesystem for samme |
WO2013007893A2 (fr) | 2011-07-12 | 2013-01-17 | Rio Tinto Alcan International Limited | Aluminerie comprenant des conducteurs electriques en materiau supraconducteur |
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 |
FR3009564A1 (fr) | 2013-08-09 | 2015-02-13 | Rio Tinto Alcan Int Ltd | Aluminerie comprenant un circuit electrique de compensation |
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)
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 |
-
1979
- 1979-11-07 FR FR7928132A patent/FR2469475A1/fr active Granted
-
1980
- 1980-04-11 HU HU811254A patent/HU191178B/hu not_active IP Right Cessation
- 1980-10-10 GR GR63115A patent/GR70348B/el unknown
- 1980-10-13 IN IN1156/CAL/80A patent/IN152568B/en unknown
- 1980-10-31 NZ NZ195424A patent/NZ195424A/en unknown
- 1980-11-03 MX MX184596A patent/MX154537A/es unknown
- 1980-11-03 YU YU2803/80A patent/YU42988B/xx unknown
- 1980-11-04 DE DE8080902175T patent/DE3070034D1/de not_active Expired
- 1980-11-04 WO PCT/FR1980/000156 patent/WO1981001299A1/fr active IP Right Grant
- 1980-11-04 RO RO104436A patent/RO82538B/ro unknown
- 1980-11-04 JP JP50257980A patent/JPS56501247A/ja active Pending
- 1980-11-04 PL PL1980227652A patent/PL132150B1/pl unknown
- 1980-11-04 BR BR8008907A patent/BR8008907A/pt unknown
- 1980-11-04 EP EP80902175A patent/EP0047246B1/fr not_active Expired
- 1980-11-06 ES ES496595A patent/ES8200410A1/es not_active Expired
- 1980-11-06 CA CA000364085A patent/CA1143695A/fr not_active Expired
- 1980-11-07 KR KR1019800004283A patent/KR850001537B1/ko active
-
1981
- 1981-05-07 OA OA57397A patent/OA08223A/fr unknown
Non-Patent Citations (1)
Title |
---|
See references of WO8101299A1 * |
Also Published As
Publication number | Publication date |
---|---|
FR2469475B1 (fr) | 1982-12-17 |
RO82538A (fr) | 1984-02-21 |
KR830004457A (ko) | 1983-07-13 |
HU191178B (en) | 1987-01-28 |
GR70348B (fr) | 1982-09-23 |
FR2469475A1 (fr) | 1981-05-22 |
KR850001537B1 (ko) | 1985-10-16 |
EP0047246B1 (fr) | 1985-01-23 |
JPS56501247A (fr) | 1981-09-03 |
CA1143695A (fr) | 1983-03-29 |
DE3070034D1 (en) | 1985-03-07 |
NZ195424A (en) | 1984-12-14 |
ES496595A0 (es) | 1981-10-16 |
BR8008907A (pt) | 1981-08-25 |
YU280380A (en) | 1984-02-29 |
YU42988B (en) | 1989-02-28 |
PL227652A1 (fr) | 1981-08-21 |
ES8200410A1 (es) | 1981-10-16 |
OA08223A (fr) | 1987-10-30 |
MX154537A (es) | 1987-09-28 |
IN152568B (fr) | 1984-02-11 |
WO1981001299A1 (fr) | 1981-05-14 |
PL132150B1 (en) | 1985-02-28 |
RO82538B (ro) | 1984-02-28 |
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