EP3523463B1 - Ensemble cathode pour cellule d'électrolyse se prêtant au procédé hall-héroult - Google Patents

Ensemble cathode pour cellule d'électrolyse se prêtant au procédé hall-héroult Download PDF

Info

Publication number
EP3523463B1
EP3523463B1 EP17857916.5A EP17857916A EP3523463B1 EP 3523463 B1 EP3523463 B1 EP 3523463B1 EP 17857916 A EP17857916 A EP 17857916A EP 3523463 B1 EP3523463 B1 EP 3523463B1
Authority
EP
European Patent Office
Prior art keywords
cathode
insert
bar
connection
end wall
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.)
Active
Application number
EP17857916.5A
Other languages
German (de)
English (en)
Other versions
EP3523463A4 (fr
EP3523463A1 (fr
Inventor
Bernard JONQUA
Abdalla ALZAROONI
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.)
Dubai Aluminium PJSC
Original Assignee
Dubai Aluminium PJSC
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 Dubai Aluminium PJSC filed Critical Dubai Aluminium PJSC
Publication of EP3523463A1 publication Critical patent/EP3523463A1/fr
Publication of EP3523463A4 publication Critical patent/EP3523463A4/fr
Application granted granted Critical
Publication of EP3523463B1 publication Critical patent/EP3523463B1/fr
Active legal-status Critical Current
Anticipated expiration legal-status Critical

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
    • 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
    • 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 invention relates to an improvement of an electrolysis cell (also called “pot") for producing aluminium by fused salt electrolysis using the Hall-Heroult-process. More precisely it relates to a cathode assembly for such electrolytic cell allowing to decrease the cathode voltage drop and modify the current distribution along the cathode assemblies in a desirable way.
  • the invention relates to a cathode assembly in which the electrical contact between the cathode material and the bus bar to which the cathode is connected involves a copper bar.
  • the Hall-Heroult process is the only continuous industrial process for producing metallic aluminium form aluminium oxide.
  • Aluminium oxide Al 2 O 3
  • molten cryolite Na 3 AlF 6
  • the resulting mixture typically at a temperature comprised between 940°C and 970°C acts as a liquid electrolyte in an electrolytic cell.
  • An electrolytic cell used for the Hall-Heroult process typically comprises a steel shell, a lining usually made from refractory bricks, a cathode usually covering the whole bottom of the pot (and which is usually made from graphite, anthracite or a mixture of both), and a plurality of anodes (usually made from carbon) that plunge into the liquid electrolyte.
  • Anodes and cathodes are connected to external bus bars.
  • An electrical current is passed through the cell (typically at a voltage between 3.8 V to 5 V) which splits the aluminium oxide in aluminium ions and oxygen ions. The oxide ions are reduced to oxygen at the anode, said oxygen reacting with the carbon of the anode.
  • the aluminium ions move to the cathode where they accept electrons supplied by the cathode; the resulting metallic aluminium is not miscible with the liquid electrolyte, has a higher density than the liquid electrolyte and will thus accumulate as a liquid metal pad on the cathode surface from where it needs to be removed from time to time, usually by suction.
  • Electrolytic cells presently used for the Hall-Heroult process are rectangular and have a length usually comprised between 8 and 20 meters and a width usually comprised between 3 and 5 meters. Most newly installed pots operate at a current intensity comprised between about 400 kA and 600 kA. They are always operated in series of several tens (up to more than a hundred) pots; within each series DC currents flow from one cell to the neighbouring cell. Much effort is still being made to optimise the process in order to increase its energy efficiency.
  • Aluminium conductors are used for the busbar systems for both anodes and cathodes.
  • aluminium cannot be used in direct contact with the cathode blocks due to its low melting point (about 660°C for pure aluminium).
  • steel bars are conventionally used for ensuring electrical contact with the cathode blocks; these so-called cathode bars are connected to cathode busbars (made from aluminium) by welded and/or bolted connectors.
  • Cathode bars are typically fitted into slots machined into the lower surface of the cathode block. Electrical contact between the steel bar and the carbon material of the cathode block can be direct, or the steel bar can be embedded in cast iron.
  • the increase in the electrical conductivity of the cathode bars implies the use of a material having a higher electrical conductivity than steel bars. All reported solutions imply the use of inserts made from a material with a higher electrical conductivity into the cathode bar, which is usually made from steel. The material with a higher electrical conductivity is usually copper. Typical solutions comprise a copper rod or bar that is inserted into a groove or slot machined into the steel cathode bar, over all or part of the length of said cathode bar.
  • FR 1 161 632 (Pechiney) discloses a copper insert fitted into a groove machined in a carbon cathode block using cast iron as a sealing material.
  • the composition of cast iron used for sealing cathode bars into the grooves of carbon cathodes is known to be critical (see US 2,953,751 assigned to Pechine, because the cast iron should not undergo any swelling due to structural transformations, as swelling could cause the carbon material to develop cracks.
  • a copper bar with circular cross section fitted into a steel bar with outer rectangular cross section and an inner "U” section, the "U” section being closed by a block see US 3,551,319 (Kaiser); a copper bar welded to a lateral face of a steel bar, see US 2,846,388 (Pechiney); a copper bar with rectangular cross section inserted into a steel tube with rectangular cross sections, see US 5,976,333 (Alcoa); a copper bar with circular cross section inserted into a steel tube with rectangular external cross section and a bore with circular cross section, see WO 2005/098093 (Aluminium Pechiney).
  • WO 2013/039893 (Alcoa) describes the use of a copper insert as a joint
  • WO 2007/071392 (SGL Carbon) describes the use of sheets made from expanded graphite
  • RU 2285754 describes the use of a carbonaceous paste.
  • Such a joint material may improve the electrical contact between the carbon block and the steel bar.
  • RU 2285754 proposes to secure the copper bar inserted into the slot of the steel bar by welded-on steel plates while allowing for a narrow cavity between the copper insert and the steel bar, i.e. the section of the copper insert is somewhat smaller than that of the groove into which it is fitted.
  • the opposite approach is taken by WO 2009/055844 describing the use of roll bonding or explosion bonding in order to obtain an excellent contact between the copper insert and the steel bar over the whole length of the insert.
  • Another problem addressed by many inventions is the connection between the copper insert and the steel cathode bar. This contact is critical for at least three reasons: the electrical contact between the copper insert and the cathode bar should be as good as possible; the thermal expansion coefficients of steel and copper are rather different and may lead to dimensional variations during the start-up of the pot; and the thermal conductivity of copper and steel is rather different, which needs to be taken into account for designing (and minimising) the heat transfer between the pot and the aluminium busbar.
  • the copper inserts do not extend along the whole length of the steel cathode bar, but a spacer section is provided at each end of the cathode bar into which the copper insert does not extend.
  • the copper bar can be made in two pieces separated in the centre of the cathode by a steel plug and/or an air gap.
  • a steel plug and/or an air gap.
  • WO 2002/42525 Servico
  • a cathode bar comprising a steel bar into which at each end a copper bar is inserted, the copper insert extending beyond the end of the steel bar and ensuring the electrical contact with the connection to the aluminium bus bar.
  • This peak current density causes local erosion of the cathode due to magnetohydrodynamic effects which are related to high magnetic fields and lead to stirring of the molten aluminium and generalized and/or localized wear on the cathode surface that is in contact with the molten metal pad.; this is particularly marked when the block is rich in graphite. Such local erosion can limit the lifetime of the cathode.
  • WO 2005/98093 describes the presence of an unsealed zone at the extremity between the cathode bar and the cathode material.
  • a similar solution is proposed in WO 2004/031452 (ALCAN) using embedding spacers. Fine tuning of the electrical conductivity of cathode blocks parallel to their length by using specially designed cathode bars with copper inserts can therefore decrease the localised cathode erosion; some of the cited documents also address the influence of thermal losses though cathode bars on magnetohydrodynamic effects, knowing that the use of copper inserts tends to lead to an increase of the thermal conductivity of the cathode bar.
  • WO 2004/059039 describes cathode assembly in which a marginal zone of the cathode block facing the collector that has a higher electrical resistance parallel to the length of the cathode block than in the centre of the cathode block; this goal is obtained by using copper inserts or plates with different thickness over different portions of the length of the steel bar, in conjunction with electrically insulating layers between the copper bar and the steel bar.
  • These cathode structures are rather difficult to manufacture and to assemble.
  • cathode bar systems allow some fine-tuning of electrical conductivity at the outer face of the cathode assembly, they are rather complex to manufacture, and do not offer much flexibility as to the conductivity profile than can be achieved over the length of the cathode block.
  • a first object of the invention is a cathode assembly suitable for a Hall-Heroult electrolysis cell, comprising
  • connection means intended to connect said cathode assembly with a cathodic bus bar
  • connection means comprise at least one first connection member extending across said slot or bore, as well as across said insert, viewed from the end,
  • the free end of said first connection member adjacent to said slot and said insert, comprises at least one connection zone for mechanical and electrical connection to said end wall of cathode bar, and in that said free end of said first connection member also comprises a non-connection zone which does neither mechanically nor electrically contact said insert.
  • said free end of first connection member comprises a central non-connection zone facing said insert, as well as two lateral connection zones provided on either side of non-connection zone, said two lateral connection zones being mechanically and electrically connected to said end wall of cathode bar, on either side of said slot.
  • said central non-connection zone is flush with said lateral connection zones.
  • said end wall of said cathode bar protrudes with respect to said end wall of said insert, by a length of protrusion inferior to 10 millimetres, in particular being equal to about 5 millimetres.
  • connection means further comprise at least one other connection member, which extends away from said insert, viewed from the end.
  • Said connection means may comprise one single first connection member, as well as two other connection members, these three connection members being located the one under the others.
  • each other connection member comprises a free end which is provided with a connection zone on said end wall of cathode bar, said connection zone extending over the whole width of said end wall.
  • Said free end of each connection member may be provided with an abutment edge for abutment against end wall of cathode bar.
  • connection zone is superior to the height of abutment edge, the ratio between height of connection zone and height of abutment edge being in particular equal to 2.
  • Said connection zones and, potentially, said non-connection zone may be provided on a bevelled edge that extends from said abutment edge.
  • each connection zone is formed by a weld.
  • the ratio between the sum of the surface areas of said welds and the whole surface area of end wall of cathode bar is superior to 45%, in particular to 55%.
  • connection member may comprise a flexible member intended to be connected to said cathode bus bar, as well as a transition member attached to said flexible member, said transition member being connected to said cathode bar and being provided with said connection zones and, potentially, said non-connection zone.
  • each flexible member is elongated viewed from the side and is rectangular in cross section.
  • Each transition member may comprise a plate made of aluminium, said plate being attached with said flexible member, as well as a block made of steel, said block being attached to said plate and being provided with said connection zones and, potentially, said non-connection zone.
  • peripheral facing walls of said groove and said cathode bar define a gap that is at least partially filled with a conductive filling material and, in the vicinity of an end wall of cathode body, said peripheral facing walls of said groove and said cathode bar define a so-called electrically non-conductive region.
  • Said electrically non-conductive region comprises an insulating member, provided at the end of said groove, which extends over at least part of the peripheral wall of said groove.
  • Said insulating member is for example at least one layer of insulating material, in particular of insulating paint.
  • said electrically non-conductive region also comprises a stopping member, provided at the end of said groove, said stopping member being adapted to prevent expansion of filling material towards the end of said groove.
  • Stopping member may be a blanket, in particular a blanket made of ceramic fiber.
  • insulating member is provided directly onto walls of the groove, whereas stopping member is provided directly onto insulating member.
  • the axial length of stopping member is inferior to that of insulating member.
  • the axial length of insulating member is for example comprised between 50 and 200 mm, typically equal to substantially 150 mm.
  • the axial length of stopping member is for example comprised between 25 and 50 mm, typically equal to substantially 40 mm.
  • the groove in cross section, is U shaped and insulating member extends from each corner of said groove, over at least part of both lateral walls of said groove.
  • the cathode assembly according to the invention may be further provided with at least a first intermediate plate made of aluminium, permanently attached to facing end of said connection member, said cathode assembly further comprising means for a removable fixation of said first intermediate plate on said cathodic bus bar.
  • Advantageously means for removable fixation of said first intermediate plate on said cathodic bus bar comprise a second intermediate plate made of aluminium, intended to be permanently attached to said cathodic bus bar, as well as means for removable fixation, in particular bolting means, between said first intermediate plate and said second intermediate plate.
  • the cathode assembly may further comprise at least one intermediate tab made of a material different from aluminium, in particular made of copper, said intermediate tab being intercalated between facing walls of said first intermediate plate and said second intermediate plate.
  • the cathode assembly may further comprise one single first intermediate plate, as well as means for a direct removable fixation of said single plate to said bus bar in a removable way, in particular by bolting means.
  • said insert has at least one first so-called electrically conductive region and at least one second so-called electrically non-conductive region, the electrically conductive contact peripheral length of said insert with said cathode body and/or said cathode bar being superior in the first region than in the second region.
  • peripheral walls of said insert may define a functional clearance with the facing walls of said body and/or said cathode bar, said functional clearance being filled with a solid non-conductive material or with air.
  • the slot or bore in cathode bar may have a substantially constant cross section over its axial length and the non-conductive region is defined by a local restriction of the cross section of the insert.
  • the insert may have a substantially constant cross section over its axial length and the non-conductive region is defined by a local widening of the cross section of the slot or bore of cathode bar.
  • the use of such non-conductive region is a simple means to locally decrease the conductivity of the cathode assembly along its length.
  • Another object of the present invention is a process for making a cathode assembly as described above, comprising the steps of
  • Said process may further comprise:
  • Connecting said first connection member to said end wall of cathode bar may be carried out before connecting said other connection member to said end wall of cathode bar.
  • Another object of the present invention is an electrolytic cell suitable for the Hall-Heroult electrolysis process, comprising a cathode forming the bottom of said electrolytic cell and comprising a plurality of parallel cathode assembly, each cathode assembly comprising at least one metallic cathode collector bar protruding out of each of the two ends of the cathode, a lateral lining defining together with the cathode a volume containing the liquid electrolyte and the liquid metal resulting from the Hall-Heroult electrolysis process, an outer metallic potshell containing said cathode and lateral lining, a plurality of anode assemblies suspended above the cathode, each anode assembly comprising at least one anode and at least one metallic anode rod connected to an anode beam, a cathodic bus bar surrounding said potshell, said bus bar being connected to at least part of said cathode assemblies said electrolytic cell being characterized in that at least one of said cathode assembly, and preferably more than 60%
  • Another object of the present invention is an electrolytic cell for the production of aluminium by the Hall-Heroult process, comprising at least one cathode assembly as described above.
  • Another object of the present invention is a process for making aluminium by the Hall-Héroult process, using an electrolytic cell provided with cathode assemblies as described above.
  • Another object of the present invention is a cathode assembly suitable for a Hall-Heroult electrolysis cell, comprising
  • Said cathode assembly may be provided with at least one optional advantageous feature, amongst those above recited in connection with cathode assembly according to first object of the present invention.
  • Another object of the present invention is a cathode assembly suitable for a Hall-Heroult electrolysis cell, comprising
  • Said further cathode assembly may be provided with at least one optional advantageous feature, amongst those above recited in connection with cathode assembly according to first object of the present invention.
  • a cathode assembly comprises a cathode body 1, a cathode bar 3 and two inserts 5 and 5'.
  • the present invention applies to cathodes used in the Hall-Heroult process that form the bottom of an electrolysis cell, said cathodes being assembled from individual cathode assembly C, each of which bears at least one cathode bar 3.
  • the Hall-Heroult process and the outline of an electrolysis cell are known to a person skilled in the art and will not be described here in great detail.
  • the cathode assembly of the invention is designated as a whole by alphanumeric reference C. It is suitable for a Hall-Heroult electrolysis cell, but could be used in other electrolytic processes.
  • the cathode assembly C first comprises a cathode body 1, of known type, which is made of a carbonaceous material, typically graphitized carbon or graphite.
  • This cathode body 1 which has an elongated shape, has opposite end walls, i.e. front 11 and rear 12 walls, as well as peripheral walls. The latter are formed by parallel upper and lower walls 13 and 14, as well as parallel side walls 15 and 16.
  • its length L1 (see figure 2 ), i.e. the distance between walls 11 and 12, is between about 3100 mm and about 3950 mm.
  • its width W1 i.e. the distance between walls 15 and 16 is between about 400 mm and about 675 mm.
  • its height H1 (see figure 1 ), i.e. the distance between walls 13 and 14, is between about 420 mm and about 580 mm.
  • the lower wall 14 of cathode body 1 is provided with a longitudinal groove 17 extending from one cathode body end to the other (see in particular figure 2 ).
  • the free end of the groove 17 leads to front 11 or rear 12 walls of body 1.
  • groove 17 Opposite side walls of groove 17 are referenced 171 and 172, whereas its upper wall is referenced 173 (see figure 3 ).
  • its width W17 i.e. the distance between walls 171 and 172, is between about 130 mm and about 280 mm.
  • its depth D17 i.e. the distance between upper wall 173 and the surface of lower wall 14, is between about 150 mm and about 240 mm.
  • the cathode assembly C also comprises two cathode bars 3 and 3', each of which is accommodated in groove 17.
  • Each cathode bar 3 or 3' is made of a first conductive material, typically steel.
  • This cathode bar 3 which has an elongated shape (see in particular figure 4 ), has opposite end walls, i.e. front 31 and rear 32 walls, as well as peripheral walls. The latter are formed by upper and lower walls 33 and 34, as well as side walls 35 and 36. Two adjacent walls form longitudinal chamfers or rounded corners 39, in a known manner.
  • upper and lower wall 33,34 and / or side walls 35,36 are parallel; in an advantageous variant of this embodiment the cathode bar is essentially rectangular in cross section.
  • the length L3 of cathode bar 3 is superior to that of length of half groove 17, so as to define a projection 38 (see in particular figure 2 ), which extends beyond front wall 11 of the cathode block body.
  • the length L38 of projection 38 is between about 350 mm and about 600 mm.
  • the width W3 of bar 3 i.e. the distance between walls 35 and 36, is slightly inferior to the width W17 of groove 17.
  • the height H3 of bar 3 i.e. the distance between walls 33 and 34, is slightly inferior to the height H17 of groove 17.
  • the upper wall 33 of cathode bar 3 is provided with a housing formed by a longitudinal slot 37.
  • this slot may be provided in another peripheral wall of cathode bar 3, in particular in side walls 35, 36; in this (less preferred) case a symmetrical configuration is preferred.
  • slot 37 extends over only a part of the whole length of the cathode bar 3.
  • rear wall, or blind wall 374 of this slot 37 is remote from facing rear wall 32 of cathode bar.
  • the distance D374 between these two walls is typically between 250 millimetres (mm) and 950 mm.
  • blind wall 374 is rounded, which makes it possible to ease the slot machining.
  • this slot 37 does lead to front wall 31 of this cathode bar.
  • slot 37' provided into other cathode bar 3' is remote from rear wall thereof, but does lead to front wall 31' of this cathode bar 3'.
  • Opposite side walls of slot 37 are referenced 371 and 372, whereas its bottom wall is referenced 373 (see figure 5 ).
  • its width W37 i.e. the distance between walls 371 and 372 is between about 50 mm and about 100 mm.
  • its depth D37 i.e. the distance between walls bottom wall 373 and the surface of upper wall 33, is between about 50 mm and about 80 mm.
  • the cathode assembly C also comprises two inserts 5 and 5', each of which is accommodated in a respective slot 37 and 37', see figures 3 , 9 , 10 and 11 .
  • Each insert 5 or 5' is made of a second conductive material, having a higher electrical conductivity than that of said first conductive material, typically copper.
  • This insert 5 which has an elongated shape, has opposite front 51 and rear 52 walls, as well as peripheral walls. The latter are formed by upper and lower walls 53 and 54, as well as side walls 55 and 56.
  • upper and lower wall 53, 54 and / or side walls 55, 56 are parallel; in an advantageous variant of this embodiment the insert 5 is essentially rectangular in cross section.
  • a steel spacer SP may be provided into the filling material F, adjacent upper wall 53 of insert 5. In a way known as such, it allows the filling material F to go around the collector bar 3.
  • the above length L5 of insert 5 is called axial length, namely along main axis of this insert.
  • This term "axial length” also applies for above mentioned lengths L1 and L3.
  • Rear wall 52 of insert 5 is in vicinity of facing rear wall 374.
  • front wall 51 of insert 5 is placed towards the bar front wall 31, and is adjusted substantially flush with this bar front wall 31.
  • the close view is showing at an enlarged scale that the copper insert end 51 is adjusted to the bar end 31.
  • L35 the longitudinal distance between above front walls 31 and 51.
  • substantially flush first means that front walls 31 and 51 are exactly flush, i.e. distance L35 is equal to 0. It also means that said distance L35 is strictly superior to 0 but in any case is inferior to 10 mm, in particular to 5 mm.
  • front wall 31 protrudes with respect to front wall 51, the protrusion length L35 being about 5 mm.
  • L35 is illustrated at a greater scale for sake of clarity; bearing in mind it is inferior to 10 mm as indicated above.
  • the expected cathode voltage drop for the arrangement described would be between 145 and 160 mV at 455 kA. This is between 95 and 110 mV less compared to the designs without copper inserts (same cathode and collector bars at same current average).
  • FIG. 13 shows connection members 2, 4, 6, also called “connectors”, which allow the connection between above described cathode bar 3 and a cathodic bus bar 100.
  • this cathodic bus bar surrounds a pot shell, not shown on this figure 13 .
  • Bus bar is rectangular in shape and has two opposite longitudinal parts, as well as two opposite transversal parts.
  • Connectors 2, 4, 6 extend between front wall 31 of cathode bar 3 and one longitudinal part of cathodic bus bar 100.
  • connection member 2, 4, 6 comprises a flexible member 21, 41, 61, as well as a transition member 22, 42, 62.
  • Flexible members 21, 41, 61 extend substantially in a parallel way, the one above the other.
  • Each flexible member which is known as such, is for example an aluminium sheet or strip. It is elongated viewed from side and, as shown on figure 13 , is substantially rectangular in cross-section. As shown by this figure 13 , each flexible member has two opposite axial ends 21a and 21b, 41a and 41b, 61a and 61b.
  • First end 21a, 41a, 61a is attached to the first intermediate plate 102, made in aluminium, whereas second end 21b, 41b, 61b is attached to cathode bar 3, via a respective transition member 22, 42, 62 which will be described more in detail hereafter.
  • First end 21a, 41a, 61a of each flexible member 21, 41, 61 is attached on bus bar 100 in a removable manner via the intermediate plate 102 bolted to the aluminium plate 104 itself welded to the bus bar 100.
  • This permanent attachment is typically carried out by welding, preferably by a respective aluminium/aluminium welding seam of known type.
  • a further plate 104 is provided, which is permanently attached to the side of bus bar 100.
  • This permanent attachment is also typically carried out by welding, preferably by a respective aluminium/aluminium welding seam of known type.
  • the two plates 102 and 104 are removably attached, by any appropriate means. In the illustrated embodiment, these two plates are provided with through bores adapted to receive removable fixation means, such as a bolt 106.
  • each tab is made of a material different from aluminium, in particular made of copper.
  • the thickness of each tab is typically 5 millimetres.
  • Adjacent faces of base plate and tab are attached by a copper/aluminium welding seam, which can be manufactured by explosion welding or co-rolling.
  • one single tab may be attached to either plate 102 or 104.
  • one single plate 102 is provided. In this case, this single plate is mechanically fixed, in a removable manner, directly on bus bar 100. Typically, said single plate receives a bolt, which penetrates into a blind hole provided into top face of bus bar 100.
  • FIG 14 shows more in detail transition members 22, 42 and 62, which are also called “clads", the structures of which are substantially identical.
  • Each transition member comprises a rear plate 23, 43 and 63, as well as a front block 24, 44 and 64, said plate and said block having substantially the same width as cathode bar 3, as illustrated in particular on figure 15 .
  • Each plate 23, 43 and 63 which is typically made of aluminium, is attached in a way known as such to a respective block 24, 44 and 64 which is typically made of steel.
  • each plate Free face of each plate, i.e. its face opposite to said block, is attached to facing end 21b, 41b, 61b of a respective flexible member 21, 41, 61.
  • said end forms a bevelled edge, defining a pocket 21c, 41c and 61c for receiving a welding material.
  • This attachment by an aluminium/aluminium welding type, is carried out in a way known as such.
  • each free face of each block 24, 44, 64 i.e. its face opposite to above plate, forms a free end of the whole connection member 2, 4, 6.
  • Said free face is attached to facing front wall 31 of cathode bar 3.
  • each free face first comprises a straight upper edge 25, 45, 65 which forms an abutment edge against cathode bar, in particular during mounting process.
  • Said upper edge is extended by a bevelled lower edge 29, 49, 69, which defines a pocket 29a, 49a, 69a, for receiving a welding material.
  • This attachment by a steel/steel welding type, is carried out in a way known as such.
  • FIG 15 shows more in detail the attachment of free face of each block 24, 44, 64 on cathode bar 3.
  • Intermediate 44 and lower 64 blocks each form a weld 46, 66 under above described upper edge 45, 65.
  • Both welds 46, 66 and upper edges 45, 65 extend across the whole cathode bar 3.
  • the height H46, H66 of each weld is superior to the height H45, H65 of each upper edge. This makes it possible to have a great welding zone between the whole transition member and the cathode bar.
  • each ratio H46 / H45 and H66 / H65 is about 2.
  • a 33 mm by 20 mm section welding is preferred (33 mm of height and 20 mm of thickness).
  • upper edge 45 of intermediate block 44 partially extends across slot 37 provided in this cathode bar, as well as across insert 5. According to the invention, this edge 45 is not mechanically connected to facing front wall 51 of insert 5.
  • abutment edge 25 does not extend across the whole width of cathode bar. Said edge is formed by two lateral abutment zones 25a and 25b, which extend on either side of a central zone 25c which faces insert 5. In the same way as described above for edge 45 and zone 27, said central zone 25c is not mechanically attached to insert 5.
  • Zones 25a, 25b of clad 24 are not welded to cathode bar, but abut against this cathode bar.
  • middle zone 25c, facing insert 5 is neither welded nor in contact with this insert 5; does the same apply for upper-mid zone of clad 44.
  • end wall 31 of cathode bar protrudes with respect to end wall 51 of insert.
  • This is an advantageous feature of the invention, since it avoids any mutual contact of clad 22 and insert 5, while welding this clad 22 onto the end face 51.
  • the position of insert 5 into slot 37 does not substantially vary in use. Therefore, even after long time of operation, insert is not likely to move into abutment against clad 22, in an inopportune manner.
  • connection members 2, 4 and 6 are provided. As variants, there may be a different number of such members.
  • one single connection member 102 is provided. This single member has substantially the same structure as that 2, but it has superior transversal dimensions.
  • upper block 124 of member 2 has an abutment edge 125 which does not extend across the whole width of cathode bar. Said edge is formed by two lateral abutment zones 125a and 125b, which extend on either side of a central zone 125c which faces insert 5. In the same way as described above, said central zone 125c is not mechanically attached to insert 5.
  • upper block forms a lower weld 126 which extends across cathode bar, but does not touch insert 5.
  • either two, or four or more members may be provided.
  • Providing two or three members is a good compromise between a satisfactory covering and a simple global structure.
  • Three members is a preferred embodiment.
  • Figure 18 shows an alternative embodiment of upper transition member, which is referenced 222 on this figure.
  • This connector has more or less the shape of a fork, with a free end formed by two branches 222a and 222b protruding beyond median recess 222c.
  • the upper part of protruding branches 222a and 222b form abutment zones, such as 25a and 25b of figures 15 and 16 , whereas the lower part of these protruding branches 222a and 222b are provided with lateral welds, such as 26a and 26b of figures 15 and 16 .
  • the upper part of recess 222c forms a central non-connection zone, such as 25c of figures 15 and 16
  • the lower part of recess 222c forms a central non-connection zone, such as 27 of figures 15 and 16 .
  • Figure 19 shows two collector bar ends of two adjacent pots, each of which is connected with a respective bus bar 100A and 100B.
  • This figure 14 also illustrates the connection of each bus bar with a respective cathode assembly according to the invention. More particularly, this connection is allowed by connection members 2A, 4A, 6A and 2B, 4B, 6B which extend between each bus bar 100A and 100B and a respective cathode bar 3A and 3B. This connection is ensured the same way as described above, in reference to figures 13 and 14 .
  • Two sets of intermediate plate 102A, 104A, 102B and 104B similar to above described plates 102 and 104, are also provided.
  • the peripheral length of insert 5 is the sum of the lengths of its sides, which contact cathode bar 3.
  • this insert comprises at least three regions, the cross-sections of which are different.
  • this insert includes two end regions 5A and 5B, which have the same cross-section, as well as an intermediate region 5C, which has a different cross-section as will be further explained.
  • the ratio L5C / L5 between the axial length L5C of intermediate region 5C and the axial length L5 of whole insert 5 is between about 8 % and about 20 %, in particular between about 9 % and about 15 %.
  • the height H5 of insert i.e. the distance between walls 53 and 54, is slightly inferior to the height H37 of slot 37. This height can differ over the whole length of insert 5, related to the longitudinal deformation of the collector bar.
  • the width of insert 5, i.e. the distance between walls 55 and 56, may not be constant over this length, which defines the above mentioned different regions.
  • the width W5A or W5B of end regions 5A and 5B substantially corresponds to that of slot 37. Therefore, once the insert 5 is placed into slot 37, there is a fit, first, between side wall 371 of said slot 37 and side walls 55A, 55B of said insert 5 and, moreover, between side wall 372 of said slot 37 and side walls 56A, 56B of said insert 5.
  • This fit which is shown on figure 11 , makes it possible to create an electric contact between cathode bar 3 and regions 5A and 5B of the insert 5.
  • side walls 55C and 56C of intermediate region 5C define recesses with side walls 55A and 56A, as well as 55B and 56B, of adjacent end regions 5A and 5B.
  • these side walls 55C and 56C are distant from facing walls 371 and 372 of slot 37, in order to define two functional gaps or clearances 7 (see figure 10 ).
  • the width W7 of these clearances i.e. the closest distances between respective walls 371, 372 of slot 37 and intermediate region 5C, is enough to avoid any electric contact between bar 3 and insert 5, in this intermediate region. In an advantageous manner, this width is greater than about 0.5 mm, in particular greater than about 0.8 mm.
  • this width W7 is between about 0.5 mm and about 2 mm, in particular between about 0.5 mm and about 1 mm.
  • Figures 10 and 11 show cross sections of insert 5 accommodated in slot 37, respectively in intermediate region 5C and in end region 5B.
  • the electrically conductive contact peripheral length of insert can be defined by the length of this insert contacting cathode bar 3, in cross section like on figures 10 and 11 .
  • This contact may be direct, like on figure 11 , or may be indirect, i.e. it is then ensured via a conductive material.
  • electrically conductive contact peripheral length is equal to the sum of the lengths of three sides of this end region 5A, i.e. H5 + W5A + H5.
  • the electrically conductive surface corresponds to the product between conductive peripheral length, as defined above, and axial length. For region 5A, this conductive surface is equal to (2* H 5 + W5A )* L55A.
  • electrically conductive peripheral length is equal to H5+W5B+H5
  • conductive surface is equal to (2* H5 + W5B )* L55B.
  • the electrically conductive contact peripheral length of insert is superior in each end region, which is therefore called electrically conductive region, than in the intermediate region, which is therefore called electrically non-conductive region.
  • the non-conductive region is placed inside the cathode block groove in such a way that it starts at the edge of the front wall 11 and/or rear wall 12 of cathode body 1 and extends towards the centre of the cathode body 1.
  • conductive ratio i.e. the ratio between, on the one hand, electrically conductive contact surface in non-conductive region and, on the other hand, electrically conductive contact surface in conductive region. In the shown example, this ratio is approximately equal to 10 %.
  • electrically conductive contact length in non-conductive region may be equal to 0, since no part of region 5C contacts cathode bar 3.
  • electrically conductive contact length in non-conductive region may equal to ( L54C + L56C ). In this case, there is only one single clearance 7, between wall 55C and cathode bar 3.
  • the insert and the slot are rectangular in cross-section, i.e. they have four peripheral walls. According to some non-illustrated variants, this insert and this slot may have different polygonal cross sections, with a different number of peripheral walls. In this case, the number of walls of the insert, contacting the cathode bar, is superior in the conductive region(s) than in the non-conductive region(s).
  • both the slot 37 and the insert 5 may be non-polygonal, but may define a portion of a circle in cross section, in particular a half circle.
  • the non shown conductive region has the same radial dimension as the slot, whereas the non-conductive region is defined by a portion 5C of the insert, the radial dimension of which is reduced.
  • the conductive ratio is equal to 0.
  • both the insert and the slot of cathode bar may be circular in cross section.
  • cathode bar differs from that 3, essentially in that the housing receiving the insert is not formed by a slot 37, but by a bore. The latter longitudinally leads to the one single end wall of this bar.
  • this bore differs from slot 37, in that it is circular in cross-section.
  • the cathode assembly of this embodiment also comprises two inserts, each of which is accommodated in a respective bore. Each insert substantially extends to the end of the bore, the same way above insert 5 substantially extends to the end of above slot 37.
  • facing walls of insert and bore may advantageously define an electrically non-conductive region, the same way facing walls of above insert 5 and above slot 37 define electrically non-conductive region.
  • the cross section of the slot is constant and the insert has at least one local tapered region, the transversal dimension of which is smaller.
  • the cross section of the insert may be constant, whereas the slot has at least one local widened region, the transversal dimension of which is larger.
  • Each widened region of the slot defines a non-conductive region of the insert.
  • the conductive region of the insert extends over the whole length thereof.
  • the cross sections of both the insert and the slot are identical, over the whole length of the insert.
  • the cathode assembly C according to the present invention can be of the same height or of different height, and/or can have a structured surface, and accordingly the cathode formed by these cathode assemblies can have a single flat upper surface (which is by far the most common cathode structure), or its upper surface can comprise regions of different heights or can be otherwise structured.
  • a conductive filling material F In a known way, the latter may be cast iron and/or with a carbonaceous intermediate material. Said intermediate carbonaceous material in direct contact with the metallic connection bar 3 must be somewhat deformable, such as to accommodate the higher thermal expansion of the metallic connection bar 3, usually made from steel, with respect to the material of the cathode assembly C.
  • compressed expanded graphite most conveniently in the form of a sheet
  • Compressed expanded graphite is available in the form of sheet of different densities and thickness from several manufacturers and under different tradenames (such as PapyexTM manufactured by Mersen and SigraflexTM manufactured by SGL).
  • the sealing paste advantageously includes carbonaceous particles dispersed in a binder that has a high carbon yield after baking.
  • Said carbonaceous particles can be graphite particles.
  • Such sealing pastes are commercially available from different manufacturers and under various tradenames (Sealing paste HCF 80 from Carbone Savoie for example).
  • the thickness of the sealing paste is calculated according to the width of the collector bar, taking into consideration the differential of thermal expansions between the steel collector bar and the graphitized cathode assembly; a thickness comprised between 15 and 25 mm can be used.
  • Figures 21 and 22 show another advantageous embodiment of the invention, wherein gaps between facing peripheral walls of cathode bar 3 and groove 17 are filled with above described filling material F.
  • These figures illustrate only cathode body 1 and the groove provided therein, but do not show cathode bar 3.
  • said peripheral facing walls of said groove and said cathode bar define a so-called electrically non-conductive region.
  • Said electrically non-conductive region comprises an insulating member, provided at the end of said groove, which extends over at least part of the peripheral wall of said groove and/or said bar.
  • Figures 21 and 22 illustrate more in detail front wall 11 of cathode body 1, as well as axial end of groove 17, i.e. the part of this groove which leads to said wall 11.
  • Said insulating member is formed by two layers 302 and 304 of insulating material, each of which extends from a respective corner 174 and 175 and covers a part of a respective side wall 171 and 172.
  • each layer 302 or 304 leads to front wall 11, i.e. cathode block extremity.
  • Said electrically non-conductive region also comprises a stopping member 306, provided at the front end of said groove.
  • said stopping member is adapted to prevent expansion of filling material out of said groove, towards front wall 11 of cathode body 1.
  • said stopping member is a blanket 306, in particular a blanket made of ceramic fiber. This stopping blanket, which is provided directly onto insulating layer 302 and 304, covers the whole cross section of the groove, i.e. both side walls and upper wall.
  • H302 or H304 of each layer 302 or 304 is comprised between 70 millimeters and 100 millimeters, typically equal to substantially 85 millimeters, whereas its so-called “axial length” L302 or L304 is comprised between 50 millimeters and 200 millimeters, typically equal to substantially 150 millimeters.
  • the axial length L306 of stopping member, which is inferior to that L302 or L304 of insulating layer, is comprised between 25 millimeters and 50 millimeters, typically equal to substantially 40 millimeters.
  • the thickness of insulating layers 302 and 304 is comprised between 0.3 millimeters and 2 millimeters, typically equal to 0.5 millimeter.
  • the thickness of said blanket 306 is comprised between 20 millimeters and 35 millimeters, typically equal to substantially 25 millimeters. For sake of clarity, the thickness of blanket 306 has been far exaggerated on figures 21 and 22 .
  • layers 302 and 304, which are placed under said blanket 306, are indicated by hatching but are illustrated without any thickness on these figures.
  • FIGS 23 and 24 illustrate an alternative embodiment of the insulating means according to the invention.
  • This variant provides one single layer 302' of insulating paint, which covers the whole cross section of the groove, i.e. both side walls 171, 172 and upper wall 173.
  • the axial dimension, as well as the thickness of this single layer are substantially identical as those above mentioned by double layers 302 and 304 (between 0.3 mm and 2 mm, typically equal to 0.5 mm).
  • this single layer 302' is covered by a blanket 306', similar to that 306 shown on figures 21 and 22 .
  • both the vertical walls 171 and 172 of the groove and the vertical walls of blanket 306 or 306' are sloped.
  • said groove defines two slight lateral protrusions, which face each other.
  • the thickness of blanket 306 or 306' is substantially constant.
  • Figures 25 and 26 illustrate alternative embodiments showing the same insulation techniques as figures 21 and 22
  • figures 27 and 28 illustrate alternative embodiments showing the same insulation techniques as figures 23 and 24
  • Figures 25 to 28 differ from figures 21 to 24 , in that vertical walls 171 and 172 of the groove and vertical walls of blanket 306 or 306' are straight. The thickness of blanket 306 or 306' is substantially constant.

Claims (15)

  1. Ensemble cathode (C) approprié pour une cellule d'électrolyse Hall-Héroult, comprenant
    - un corps de cathode (1) réalisé en un matériau carboné ;
    - au moins une barrette de cathode (3, 3') réalisée en un premier matériau conducteur, ladite barrette de cathode étant logée dans une rainure (17) prévue dans ledit corps de cathode ;
    - au moins un insert (5, 5') réalisé en un deuxième matériau conducteur, ayant une conductivité électrique supérieure à celle dudit premier matériau conducteur, ledit insert étant logé dans une fente (37) ou un alésage prévu dans ladite barrette de cathode ;
    caractérisé en ce que ladite fente (37) débouche sur une paroi d'extrémité (31) de ladite barrette de cathode (3), et une paroi d'extrémité (51) dudit insert (5) affleure sensiblement ladite paroi d'extrémité (31) de ladite barrette de cathode,
    en ce que ledit ensemble cathode est en outre pourvu de moyens de connexion (2, 4, 6) destinés à connecter ledit ensemble cathode à une barre-bus cathodique (100),
    en ce que lesdits moyens de connexion comprennent au moins un premier élément de connexion (2) s'étendant à travers ladite fente (37) ou ledit alésage, ainsi qu'à travers ledit insert (5), vu depuis l'extrémité,
    en ce que l'extrémité libre dudit premier élément de connexion (2) adjacente à ladite fente et audit insert, comprend au moins une zone de connexion (26a, 26b) pour la connexion mécanique et électrique à ladite paroi d'extrémité (31) de la barrette de cathode,
    et en ce que ladite extrémité libre dudit premier élément de connexion (2) comprend également une zone de non-connexion (27) qui n'est en contact ni mécanique, ni électrique avec ledit insert (5).
  2. Ensemble cathode selon la revendication 1, caractérisé en ce que ladite extrémité libre du premier élément de connexion (2) comprend une zone de non-connexion centrale (27) faisant face audit insert, ainsi que deux zones de connexion latérales (26a, 26b) prévues de chaque côté de la zone de non-connexion (27), lesdites deux zones de connexion latérales étant connectées mécaniquement et électriquement à ladite paroi d'extrémité (31) de la barrette de cathode, de chaque côté de ladite fente (37), ladite zone de non-connexion centrale (27) affleurant de préférence lesdites zones de connexion latérales (26a, 26b).
  3. Ensemble cathode selon l'une quelconque des revendications ci-dessus, caractérisé en ce que ladite paroi d'extrémité (31) de ladite barrette de cathode fait saillie par rapport à ladite paroi d'extrémité (51) dudit insert (5), d'une longueur de saillie (L35) qui est inférieure à 10 millimètres, en particulier d'environ 5 millimètres.
  4. Ensemble cathode selon l'une quelconque des revendications ci-dessus, caractérisé en ce que lesdits moyens de connexion (2, 4, 6) comprennent en outre au moins un autre élément de connexion (4, 6) qui s'étend en s'éloignant dudit insert, vu depuis l'extrémité, lesdits moyens de connexion comprenant de préférence un premier élément de connexion (2) unique, ainsi que deux autres éléments de connexion (4, 6), ces trois éléments de connexion étant situés l'un sous les autres.
  5. Ensemble cathode selon la revendication 4, caractérisé en ce que chaque autre élément de connexion (4, 6) comprend une extrémité libre qui est pourvue d'une zone de connexion (46, 66) sur ladite paroi d'extrémité (31) de la barrette de cathode, ladite zone de connexion s'étendant sur toute la largeur de ladite paroi d'extrémité (31).
  6. Ensemble cathode selon l'une quelconque des revendications 4 et 5, caractérisé en ce que ladite extrémité libre de chaque élément de connexion (2, 4, 6) est pourvue d'un bord de butée (25, 45, 65) pour la mise en butée contre la paroi d'extrémité (31) de la barrette de cathode, la hauteur de la zone de connexion (26a, 26b, 46, 66) étant de préférence supérieure à la hauteur du bord de butée (25, 45, 65), le rapport entre la hauteur de la zone de connexion et la hauteur du bord de butée étant en particulier égal à 2.
  7. Ensemble cathode selon l'une quelconque des revendications ci-dessus, caractérisé en ce que chaque zone de connexion est formée par une soudure (26a, 26b, 46, 66), le rapport entre la somme des zones de surfaces (S26a, S26b, S46, S66) desdites soudures (26a, 26b, 46, 66) et toute la zone de surface de la paroi d'extrémité de la barrette de cathode étant de préférence supérieur à 45 %, en particulier 55 %.
  8. Ensemble cathode selon l'une quelconque des revendications ci-dessus, caractérisé en ce que chaque élément de connexion (2, 4, 6) comprend un élément flexible (21, 41, 61) destiné à être connecté à ladite barrette de bus de cathode, ainsi qu'un élément de transition (22, 42, 62) fixé audit élément flexible, ledit élément de transition étant connecté à ladite barrette de cathode et étant pourvu desdites zones de connexion (26a, 26b, 46, 66), et potentiellement de ladite zone de non-connexion (27), et dans lequel chaque élément de transition (22, 42, 62) comprend avantageusement
    - une plaque (23, 43, 63) réalisée en aluminium, ladite plaque étant fixée audit élément flexible, ainsi que
    - un bloc (24, 44, 64) réalisé en acier, ledit bloc étant fixé à ladite plaque et étant pourvu desdites zones de connexion (26a, 26b, 46, 66), et potentiellement de ladite zone de non-connexion (27).
  9. Ensemble cathode selon l'une quelconque des revendications ci-dessus, caractérisé en ce que des parois périphériques en regard de ladite rainure (17) et de ladite barrette de cathode (3) définissent un écart qui est au moins partiellement rempli d'un matériau de remplissage conducteur (F) et en ce qu'au voisinage d'une paroi d'extrémité (11) du corps de cathode (1), lesdites parois périphériques en regard de ladite rainure et de ladite barrette de cathode définissent une région dite non conductrice de l'électricité (302, 304, 306 ; 302', 306').
  10. Ensemble cathode selon la revendication 9, caractérisé en ce que ladite région non conductrice de l'électricité comprend un élément isolant (302, 304 ; 302'), prévu à l'extrémité de ladite rainure, qui s'étend sur au moins une partie de la paroi périphérique de ladite rainure, la longueur axiale (L302, L304 ; L302') dudit élément isolant étant de préférence comprise entre 50 et 200 mm, généralement égale à sensiblement 150 mm, et/ou ledit élément isolant étant de préférence au moins une couche (302, 304 ; 302') de matériau isolant, en particulier de peinture isolante.
  11. Ensemble cathode selon la revendication 9, caractérisé en ce que ladite région non conductrice de l'électricité comprend également un élément d'arrêt (306 ; 306'), prévu à l'extrémité de ladite rainure, ledit élément d'arrêt étant adapté pour empêcher une expansion du matériau de remplissage (F) vers l'extrémité de ladite rainure, et ledit élément d'arrêt étant de préférence une couverture (306 ; 306'), en particulier une couverture réalisée en fibre céramique.
  12. Ensemble cathode selon l'une quelconque des revendications ci-dessus, caractérisé en ce que ledit insert a au moins une première région dite électriquement conductrice et au moins une deuxième région dite non conductrice de l'électricité, la longueur périphérique de contact électriquement conducteur dudit insert, avec ledit corps de cathode et/ou ladite barrette de cathode étant plus importante dans la première région que dans la deuxième région.
  13. Ensemble cathode selon la revendication 12, caractérisé en ce que, dans la région non conductrice, des parois périphériques dudit insert définissent un espace fonctionnel avec les parois en regard dudit corps et/ou de ladite barrette de cathode, ledit espace fonctionnel étant rempli d'un matériau solide non conducteur ou d'air, dans lequel de préférence
    • la fente ou l'alésage de la barrette de cathode a une section transversale sensiblement constante sur sa longueur axiale, et
    • la région non conductrice est définie par une restriction locale de la section transversale de l'insert.
  14. Ensemble cathode selon la revendication 13, caractérisé en ce que l'insert a une section transversale sensiblement constante sur sa longueur axiale, et la région non conductrice est définie par un élargissement local de la section transversale de la fente ou de l'alésage de la barrette de cathode.
  15. Processus de fabrication d'un ensemble cathode selon l'une quelconque des revendications ci-dessus, comprenant les étapes suivantes :
    a) fournir un corps de cathode réalisé en un matériau carboné ;
    b) fournir une rainure ou un alésage dans ledit corps de cathode ;
    c) fournir au moins une barrette de cathode réalisée en un premier matériau conducteur, ladite barrette de cathode étant logée dans ladite rainure ou ledit alésage prévu(e) dans ledit corps de cathode ;
    d) fournir une fente ou un alésage dans ladite barrette de cathode, ladite fente ou ledit alésage débouchant sur une paroi d'extrémité de ladite barrette de cathode ;
    e) fournir au moins un insert réalisé en un deuxième matériau conducteur, ayant une conductivité électrique supérieure à celle dudit premier matériau conducteur, ledit insert étant logé dans ladite fente ou ledit alésage prévu(e) dans ladite barrette de cathode, une paroi d'extrémité dudit insert affleurant sensiblement ladite paroi d'extrémité de ladite barrette de cathode ;
    f) fournir au moins un premier élément de connexion (2)
    g) connecter ledit premier élément de connexion (2) à ladite paroi d'extrémité (31) de la barrette de cathode de chaque côté de ladite fente, de manière à ce que, sur l'extrémité libre dudit premier élément de connexion adjacente à ladite fente et audit insert, elle forme au moins une zone de connexion (26a, 26b) pour la connexion mécanique et électrique à ladite paroi d'extrémité (31) de la barrette de cathode, et en ce que ladite extrémité libre dudit premier élément de connexion (2) forme également une zone de non-connexion (27) qui n'est en contact ni mécanique, ni électrique avec ledit insert (5), ledit processus comprenant en outre facultativement
    - la fourniture d'au moins un autre élément de connexion (4, 6),
    - la connexion dudit autre élément de connexion (4, 6) à ladite paroi d'extrémité (31) de la barrette de cathode, de telle manière que ledit autre élément de connexion (4, 6) s'étende en s'éloignant dudit insert, vu de face, sachant que la connexion dudit premier élément de connexion (2) à ladite paroi d'extrémité (31) de la barrette de cathode est avantageusement effectuée avant la connexion dudit autre élément de connexion (4, 6) à ladite paroi d'extrémité (31) de la barrette de cathode.
EP17857916.5A 2016-10-05 2017-09-19 Ensemble cathode pour cellule d'électrolyse se prêtant au procédé hall-héroult Active EP3523463B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB1616873.4A GB2554702A (en) 2016-10-05 2016-10-05 Cathode assembly for electrolytic cell suitable for the Hall-Héroult process
PCT/IB2017/055653 WO2018065844A1 (fr) 2016-10-05 2017-09-19 Ensemble cathode pour cellule d'électrolyse se prêtant au procédé hall-héroult

Publications (3)

Publication Number Publication Date
EP3523463A1 EP3523463A1 (fr) 2019-08-14
EP3523463A4 EP3523463A4 (fr) 2020-06-17
EP3523463B1 true EP3523463B1 (fr) 2021-02-17

Family

ID=57571079

Family Applications (1)

Application Number Title Priority Date Filing Date
EP17857916.5A Active EP3523463B1 (fr) 2016-10-05 2017-09-19 Ensemble cathode pour cellule d'électrolyse se prêtant au procédé hall-héroult

Country Status (3)

Country Link
EP (1) EP3523463B1 (fr)
GB (1) GB2554702A (fr)
WO (1) WO2018065844A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113073358B (zh) * 2021-04-06 2024-03-08 李欣 一种复合阴极钢棒和阴极炭块组的结构

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AUPM621394A0 (en) * 1994-06-10 1994-07-07 Mitchell, John Cathode connection for aluminium smelter pot
US6231745B1 (en) * 1999-10-13 2001-05-15 Alcoa Inc. Cathode collector bar
NO315090B1 (no) * 2000-11-27 2003-07-07 Servico As Anordninger for å före ström til eller fra elektrodene i elektrolyseceller,fremgangsmåter for fremstilling derav, samt elektrolysecelle forfremstilling av aluminium ved elektrolyse av alumina löst i en smeltetelektrolytt
AU2003271461A1 (en) * 2002-10-02 2004-04-23 Alcan International Limited Collector bar providing discontinuous electrical connection to cathode block
FR2868435B1 (fr) * 2004-04-02 2006-05-26 Aluminium Pechiney Soc Par Act Element cathodique pour l'equipement d'une cellule d'electrolyse destinee a la production d'aluminium
TW200925328A (en) * 2007-10-29 2009-06-16 Bhp Billiton Aluminium Technologies Ltd Composite collector bar
FR2964984B1 (fr) * 2010-09-17 2012-08-31 Alcan Int Ltd Dispositif de connexion electrique entre deux cellules successives d'aluminium
CN203866387U (zh) * 2014-05-19 2014-10-08 包头市中硕焊接科技有限公司 电解槽用阴极钢棒与铝软带的焊接结构
GB2536901A (en) * 2015-03-30 2016-10-05 Dubai Aluminium Pjsc Cathode block for electrolytic cell suitable for the Hall-Héroult process
GB2542150A (en) * 2015-09-09 2017-03-15 Dubai Aluminium Pjsc Cathode assembly for electrolytic cell suitable for the Hall-Héroult process

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Also Published As

Publication number Publication date
WO2018065844A1 (fr) 2018-04-12
GB2554702A (en) 2018-04-11
GB201616873D0 (en) 2016-11-16
EP3523463A4 (fr) 2020-06-17
EP3523463A1 (fr) 2019-08-14

Similar Documents

Publication Publication Date Title
EP1927679B1 (fr) Cellule d'électrolyse destinée à la production d'aluminium avec un moyen pour la diminution de la chute de tension
CN101432466B (zh) 具有非平面凹槽设计的铝电解槽用阴极
US11136682B2 (en) Cathode current collector for a Hall-Heroult cell
CA2980832C (fr) Bloc de cathode pour cellule electrolytique convenant pour le procede hall/heroult
CA2347858C (fr) Barre collectrice de cathode avec element d'espacement permettant d'ameliorer le bilan thermique
EP3347509B1 (fr) Ensemble cathode pour cellule d'électrolyse approprié pour le procédé hall-héroult
EP3523463B1 (fr) Ensemble cathode pour cellule d'électrolyse se prêtant au procédé hall-héroult
EP3571333B1 (fr) Ensemble cathode avec barre collectrice métallique pour cellule d'électrolyse se prêtant au procédé hall-héroult
WO2017168310A1 (fr) Bloc cathode à insert cuivre-aluminium pour cellule électrolytique convenant au procédé hall-héroult
CA3179811A1 (fr) Ensemble cathode avec systemes de barres collectrices metalliques pour cellule d'electrolyse se pretant au procede hall-heroult

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

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

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

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20190506

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent

Extension state: BA ME

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
A4 Supplementary search report drawn up and despatched

Effective date: 20200519

RIC1 Information provided on ipc code assigned before grant

Ipc: C25C 3/08 20060101AFI20200513BHEP

Ipc: C25C 3/16 20060101ALI20200513BHEP

REG Reference to a national code

Ref country code: DE

Ref legal event code: R079

Ref document number: 602017032975

Country of ref document: DE

Free format text: PREVIOUS MAIN CLASS: C25C0003060000

Ipc: C25C0003080000

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

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

Free format text: STATUS: GRANT OF PATENT IS INTENDED

RIC1 Information provided on ipc code assigned before grant

Ipc: C25C 3/16 20060101ALI20201124BHEP

Ipc: C25C 3/08 20060101AFI20201124BHEP

INTG Intention to grant announced

Effective date: 20201211

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

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

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 602017032975

Country of ref document: DE

REG Reference to a national code

Ref country code: AT

Ref legal event code: REF

Ref document number: 1361568

Country of ref document: AT

Kind code of ref document: T

Effective date: 20210315

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: NO

Ref legal event code: T2

Effective date: 20210217

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG9D

REG Reference to a national code

Ref country code: NL

Ref legal event code: MP

Effective date: 20210217

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

Ref country code: BG

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210517

Ref country code: LT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210518

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

Ref country code: HR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

Ref country code: PT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210617

REG Reference to a national code

Ref country code: AT

Ref legal event code: MK05

Ref document number: 1361568

Country of ref document: AT

Kind code of ref document: T

Effective date: 20210217

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

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

Ref country code: RS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

Ref country code: LV

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

Ref country code: PL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

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

Ref country code: EE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

Ref country code: CZ

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

Ref country code: AT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

Ref country code: SM

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 602017032975

Country of ref document: DE

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

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

Ref country code: RO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

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: 20211118

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 FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

Ref country code: AL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

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

Ref country code: SI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

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 FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

REG Reference to a national code

Ref country code: BE

Ref legal event code: MM

Effective date: 20210930

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

Effective date: 20210919

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

Ref country code: MC

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

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

Ref country code: LU

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

Effective date: 20210919

Ref country code: IE

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

Effective date: 20210919

Ref country code: GB

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

Effective date: 20210919

Ref country code: BE

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

Effective date: 20210930

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

Ref country code: LI

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

Effective date: 20210930

Ref country code: CH

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

Effective date: 20210930

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

Ref country code: CY

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217

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

Ref country code: HU

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT; INVALID AB INITIO

Effective date: 20170919

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

Ref country code: IS

Payment date: 20230928

Year of fee payment: 7

Ref country code: FR

Payment date: 20230914

Year of fee payment: 7

Ref country code: DE

Payment date: 20230928

Year of fee payment: 7

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

Ref country code: NO

Payment date: 20230929

Year of fee payment: 7

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

Ref country code: MK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20210217