WO2023119802A1 - Ensemble cathode - Google Patents

Ensemble cathode Download PDF

Info

Publication number
WO2023119802A1
WO2023119802A1 PCT/JP2022/038136 JP2022038136W WO2023119802A1 WO 2023119802 A1 WO2023119802 A1 WO 2023119802A1 JP 2022038136 W JP2022038136 W JP 2022038136W WO 2023119802 A1 WO2023119802 A1 WO 2023119802A1
Authority
WO
WIPO (PCT)
Prior art keywords
collector
collector bar
cathode
cathode assembly
bars
Prior art date
Application number
PCT/JP2022/038136
Other languages
English (en)
Japanese (ja)
Inventor
涼 秋田
泰弘 小山
拓也 津田
キルジュ、ジェレミー
モレナール、デイビッド
Original Assignee
Ｓｅｃカーボン株式会社
コモンウェルス サイエンティフィック アンド インダストリアル リサーチ オーガナイゼーション
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 Ｓｅｃカーボン株式会社, コモンウェルス サイエンティフィック アンド インダストリアル リサーチ オーガナイゼーション filed Critical Ｓｅｃカーボン株式会社
Publication of WO2023119802A1 publication Critical patent/WO2023119802A1/fr

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B21/00—Obtaining 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
    • C25C3/08—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
    • C25C7/00—Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells
    • C25C7/02—Electrodes; Connections thereof
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces
    • F27B3/08—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces heated electrically, with or without any other source of heat

Definitions

  • the present invention relates to a cathode assembly.
  • a cathode block made of carbon is used for the cathode of the electrolytic furnace for aluminum smelting.
  • the cathode block is installed in a steel box called a shell and constitutes the bottom of the electrolytic furnace.
  • the cathode block is also responsible for supplying electrons to the electrolytic bath.
  • Electrons are supplied to the cathode block through a metal collector bar.
  • the assembly in which the collector bar is connected to the cathode block will be referred to as the "cathode assembly”.
  • connection between the cathode block and the collector bar is made by casting iron. Specifically, a groove is formed in the bottom surface of the cathode block, a collector bar is fitted into the groove, and molten iron heated to about 1250° C. is poured into the gap.
  • WO2018/134754 discloses a cathode assembly comprising a cathode body made of carbonaceous material and at least one cathode collector bar made of metal material.
  • This cathode collector bar has two bar elements. Each of the two bar elements has a tapered surface and a major side surface that contacts the side surface of the slot in the cathode body. The two tapered surfaces form a line of contact between the two bar elements.
  • Japanese National Publication of International Patent Application No. 2017-534770 discloses a cathode current collector assembly assembled within a carbon cathode.
  • the cathode current collector assembly comprises a highly conductive metal current collector bar positioned below the carbon cathode.
  • the current collector bar has a conductive flexible foil or sheet at the interface with the carbon cathode.
  • US Pat. No. 7,776,190 discloses a cathode for use in aluminum electrolytic cells.
  • the cathode is selected from a carbon cathode block or a graphite cathode block, comprising a cathode block having collector bar slots therein, iron collector bars positioned in the collector bar slots, and expanded graphite lined in the collector bar slots.
  • FIG. 10 of the same publication shows that contact resistance can be reduced by placing a foil of expanded graphite in the cathode slot (groove).
  • the method of casting iron described above has a large workload, and energy costs are required for heating to melt the iron and preheating the cathode block and collector bar. Also, if the preheating temperature is too high, the cathode block will oxidize, so the preheating temperature can only be raised to 400 to 500°C, and there is a risk that the cathode block will crack due to heat shock when molten iron is poured.
  • Electric furnace startup is generally carried out using a method called resistor baking, which raises the temperature using resistance heat.
  • resistor baking a DC current is passed through an electrolytic furnace to raise the temperature of the furnace by resistance heat.
  • the current concentrates in some cathode assemblies with high contact pressure, and abnormal temperature rise occurs in those cathode assemblies.
  • the thermal expansion of the collector bars increases, and the cathode blocks and the collector bars come into even stronger contact. This results in lower contact resistance and more current crowding at the cathode assembly. There is a risk that the cathode block will crack due to the heat shock caused by this mechanism.
  • a cathode assembly is a cathode assembly for use in an electrolytic furnace for smelting aluminum, comprising a carbon cathode block provided with grooves and a collector bar unit inserted into the grooves.
  • the collector bar unit includes two metal collector bars each having a shape extending in the same direction as the groove and arranged side by side in the width direction of the groove; and the two collector bars.
  • a spacing adjustment member for adjusting the spacing of the bars the spacing adjustment member including a mechanism for adjusting the spacing between the two collector bars by a screw.
  • connection work between the cathode block and the collector bar can be simplified. According to the present invention, it is also possible to suppress variations in contact resistance between the cathode block and the collector bar that occur when the temperature of the electrolytic furnace is increased.
  • FIG. 1 is a cross-sectional view schematically showing the overall configuration of an example of an electrolytic furnace for aluminum smelting.
  • FIG. 2 is a perspective view schematically showing the configuration of the cathode assembly according to the first embodiment of the invention.
  • 3 is a cross-sectional view taken along line III-III of FIG. 2.
  • FIG. 4 is an exploded perspective view schematically showing the configuration of a collector bar unit included in the cathode assembly of FIG. 2.
  • FIG. FIG. 5 is an exploded perspective view schematically showing the configuration of a collector bar unit included in a cathode assembly according to a second embodiment of the invention.
  • FIG. 6 is an exploded perspective view schematically showing the configuration of a collector bar unit included in a cathode assembly according to a third embodiment of the invention.
  • FIG. 7 is a cross-sectional view schematically showing the structure of a gap adjusting member included in the collector bar unit of FIG. 6.
  • FIG. 8 is a schematic cross-sectional view showing an example of arrangement of conductive members.
  • FIG. 9 is a schematic cross-sectional view showing an example of arrangement of conductive members.
  • FIG. 10 is a schematic cross-sectional view showing an example of arrangement of conductive members.
  • FIG. 11 is a perspective view schematically showing the configuration of one example of the collector bar.
  • FIG. 12 is a perspective view schematically showing the configuration of another example of the collector bar.
  • FIG. 13 is a cross-sectional view schematically showing the construction of a cathode assembly according to a sixth embodiment of the invention.
  • FIG. 14 is a cross-sectional view schematically showing the configuration of an example of a cathode assembly having a double-slot type cathode block.
  • FIG. 15 is a cross-sectional view schematically showing the construction of a cathode assembly according to a seventh embodiment of the invention.
  • FIG. 16 is a cross-sectional view schematically showing the configuration of a test device used to measure changes in contact pressure caused by thermal expansion.
  • FIG. 17 is a photograph of the test device.
  • FIG. 18 is a graph showing the relationship between temperature and load.
  • FIG. 1 is a cross-sectional view schematically showing the overall configuration of an electrolytic furnace 1, which is an example of an electrolytic furnace for aluminum smelting.
  • the electrolytic furnace 1 comprises a cathode assembly 100 according to the first embodiment of the invention.
  • a plurality of cathode assemblies 100 are arranged side by side in the depth direction (y direction) of FIG.
  • Each cathode assembly 100 comprises a carbon cathode block 10 and two collector bar units 20 .
  • the cathode block 10 constitutes the furnace bottom of the electrolytic furnace 1 .
  • Each of the collector bar units 20 includes a metallic collector bar, which will be described in detail later, and is electrically connected to the cathode block 10 by this collector bar. One end of each collector bar unit 20 is pulled out of the electrolytic furnace 1 .
  • the electrolytic furnace 1 includes, in addition to the cathode assembly 100, an anode 91, a shell 92, a lining 93 and the like. Inside the electrolytic furnace 1, a melt 94 containing aluminum oxide is accommodated.
  • the collector bar unit 20 and anode 91 are electrically connected to a power supply (not shown).
  • a voltage is applied between cathode block 10 and anode 91 by a power supply.
  • the aluminum oxide in the melt 94 is reduced to produce aluminum 95 .
  • FIG. 2 is a perspective view schematically showing the configuration of the cathode assembly 100.
  • FIG. FIG. 3 is a cross-sectional view taken along line III--III in FIG.
  • the cathode assembly 100 includes the cathode block 10 and two collector bar units 20, as described above.
  • Cathode block 10 is made of carbon. "Cathode block made of carbon” also includes a cathode block made of a composite material such as TiB2 or TiC and carbon. Cathode block 10 is preferably made of graphite.
  • the cathode block 10 has a rectangular parallelepiped shape and has a groove 10a on its bottom surface. The groove 10a is open not only on the bottom surface of the cathode block 10, but also on the side surface of the cathode block 10 (the surface perpendicular to the x direction in FIG. 2). Two collector bar units 20 are inserted into the groove 10a.
  • Each collector bar unit 20 includes two collector bars (collector bar 21 and collector bar 22) and a plurality of interval adjusting members 23 (Fig. 3).
  • Each of collector bar 21 and collector bar 22 is made of metal, preferably iron.
  • Each of collector bar 21 and collector bar 22 has a shape extending in the same direction (x direction in FIG. 2) as groove 10a.
  • the collector bar 21 and the collector bar 22 are arranged side by side in the width direction of the groove 10a inside the groove 10a. More specifically, the width direction of the groove 10a is a direction (y direction in FIG. 2) perpendicular to both the direction in which the groove 10a extends (x direction in FIG. 2) and the vertical direction (z direction in FIG. 2). be.
  • the spacing adjusting member 23 (FIG. 3) is arranged between the collector bars 21 and 22 to adjust the spacing s between the collector bars 21 and 22. A detailed configuration of the gap adjusting member 23 and a method for adjusting the gap s will be described later.
  • Each of the collector bar 21 and the collector bar 22 has a surface 211 and a surface 221 (FIG. 3) that come into contact with the side surfaces of the groove 10a.
  • Each of the surfaces 211 and 221 is preferably a surface that closely follows the side surfaces of the groove 10a with which they are in contact.
  • FIG. 2 and 3 show the case where the groove 10a of the cathode block 10 has a trapezoidal cross-sectional shape in a cross section perpendicular to the direction in which the groove 10a extends (the yz cross section in FIG. 3), the opening of which becomes smaller toward the bottom surface. showing.
  • This cross-sectional shape is a preferable shape because it can prevent the collector bar unit 20 from falling off from the bottom surface.
  • the cross-sectional shape of the groove 10a is arbitrary.
  • the cross-sectional shape of the groove 10a may be rectangular, for example.
  • each of the surfaces 211 and 221, which are surfaces in contact with the side surface of the groove 10a, is preferably a surface that closely follows the side surface of the groove 10a with which they are in contact.
  • the gap between the collector bars 21 and 22 is preferably filled with a filler.
  • the filler is cement, for example.
  • a spacer made of thermoplastic resin or a metal or alloy having a melting point of 700°C or less is arranged between the collector bars 21 and 22.
  • the collector bar 21 and the collector bar 22 at least one between the collector bar 21 and the filler and between the collector bar 22 and the filler when the above-described filler is filled
  • spacers made of a thermoplastic resin or a metal or alloy having a melting point of 700° C. or less are arranged.
  • a metal having a melting point of 700° C. or lower is, for example, aluminum.
  • the spacer is more preferably sheet-shaped.
  • FIG. 4 is an exploded perspective view schematically showing the configuration of the collector bar unit 20.
  • the collector bar unit 20 includes collector bars 21 and collector bars 22 and a plurality of interval adjusting members 23 .
  • the interval adjusting members 23 are arranged between the collector bars 21 and 22 at approximately equal intervals along the length direction of the collector bars 21 and 22 .
  • the gap adjusting member 23 is arranged only inside the cathode block 10 when the collector bar unit 20 is inserted into the groove 10a (FIG. 2) of the cathode block 10, and is arranged outside the cathode block 10. Not placed.
  • the conductivity of the gap adjusting member 23 may be high or low.
  • the interval adjusting member 23 is made of metal, for example.
  • Each of the interval adjusting members 23 has a threaded portion 23a at one end and a threaded portion 23b at the other end.
  • the collector bar 21 is formed with a threaded hole 21a to be fastened with the threaded portion 23a.
  • the collector bar 22 is formed with a threaded hole 22a to be fastened with the threaded portion 23b. According to this configuration, the distance s (see FIG. 3 ) can be adjusted.
  • the threaded portion 23a and the threaded portion 23b are formed with threads in directions opposite to each other. That is, when the threaded portion 23a is a right-handed thread, the threaded portion 23b is a left-handed thread. When the threaded portion 23a is left-handed, the threaded portion 23b is right-handed. According to this configuration, when the interval adjusting member 23 is rotated in one direction, the threaded portion 23a and the threaded portion 23b can be moved in a tightening (or loosening) direction. Thereby, the collector bar 21 and the collector bar 22 can be moved evenly.
  • the collector bar unit 20 includes the collector bars 21 and 22 arranged side by side in the width direction of the groove 10a.
  • the collector bar unit 20 further includes a spacing adjustment member 23 that adjusts the spacing s (FIG. 3) between the collector bars 21 and 22. As shown in FIG.
  • the distance adjusting member 23 is rotated in a direction in which the distance s is further increased. contact pressure can be increased. On the contrary, the contact pressure between each of the collector bars 21 and 22 and the cathode block 10 can be reduced by rotating the gap adjusting member 23 in the direction in which the gap s becomes smaller.
  • the contact pressure between each of the collector bars 21 and 22 and the cathode block 10 can be adjusted. Thereby, the contact resistance between each of collector bar 21 and collector bar 22 and cathode block 10 can be adjusted.
  • the gap between the collector bar and the groove 10a may vary due to variations in processing.
  • contact resistance may vary, particularly in a low temperature range (for example, a temperature range from room temperature to about 500° C.).
  • Multiple cathode assemblies 100 may be used in the electrolysis furnace 1 (FIG. 1).
  • the temperature of the electrolytic furnace 1 is generally raised from room temperature to near the operating temperature (eg, about 960° C.) by electrical resistance heating (resistor-bake). If there is variation in contact resistance among the plurality of cathode assemblies 100, current may concentrate in the cathode assembly 100 with low contact resistance during temperature rise, causing a local temperature rise. Even during operation, current concentration on the cathode assembly 100 with low contact resistance causes local wear on the cathode electrolysis surface, and uneven heat balance causes problems such as destabilization of operation.
  • molten iron is poured in to fill the gap between the collector bar and the groove 10a.
  • this iron casting method requires a large workload.
  • the connection work between the cathode block and the collector bar can be simplified compared to the method of casting iron. Also, energy costs for heating for melting iron and preheating the cathode block and collector bar can be reduced. Furthermore, since there is no risk of cracking due to heat shock, manufacturing costs can be reduced.
  • the contact pressure between each of the collector bars 21 and 22 and the cathode block 10 fluctuates due to the thermal expansion of the cathode block 10, the collector bars 21 and the collector bars 22.
  • temperature gradients may occur within the electrolytic furnace 1, and thermal expansion may be non-uniform within the electrolytic furnace.
  • FIG. 10 of US Pat. No. 7,776,190 shows that low contact resistance can be achieved by placing a foil of expanded graphite in the cathode slot.
  • the contact resistance rapidly changes from a value of 100 m ⁇ cm 2 or more to a value of about 25 m ⁇ cm 2 as the contact pressure increases. I understand.
  • the contact resistance will also become non-uniform and drift may occur. If the degree of non-uniformity is large, a partial rapid temperature rise may occur, and the cathode block 10 may be partially oxidized or cracked.
  • the contact pressure can be adjusted in advance to a predetermined level (for example, 2 N/mm 2 ) or more at room temperature by the gap adjusting member 23 .
  • a predetermined level for example, 2 N/mm 2
  • the contact pressure can be finely controlled because the spacing adjusting member 23 includes a mechanism for adjusting the spacing s with a screw.
  • the contact pressure can be adjusted over the entire length direction of the collector bars 21 and 22. can.
  • the gap between the collector bars 21 and 22 After adjusting the contact pressure with the gap adjusting member 23, it is preferable to fill the gap between the collector bars 21 and 22 with a filler.
  • Cathode assembly 100 is heated to a high temperature (eg, 960° C.) during operation. Thermal expansion of the collector bars 21 and 22 may deform the gap adjusting member 23 .
  • a high temperature eg, 960° C.
  • a spacer made of a thermoplastic resin or a metal or alloy having a melting point of 700° C. or less between the collector bars 21 and 22 .
  • a spacer made of a thermoplastic resin or a metal or alloy having a melting point of 700° C. or lower stress due to thermal expansion of the collector bars 21 and 22 can be relaxed, and damage to the cathode block 10 can be suppressed. .
  • FIG. 4 illustrates a case where the collector bar unit 20 includes six interval adjusting members 23, the number of interval adjusting members 23 is arbitrary.
  • the number of interval adjusting members 23 may be one. However, if a plurality of interval adjusting members 23 are arranged along the length direction of the collector bars 21 and 22, the contact pressure with the cathode block 10 can be adjusted over the length direction of the collector bars 21 and 22, which is preferable. . When a plurality of interval adjusting members 23 are arranged, the interval at which the interval adjusting members 23 are arranged may not be equal.
  • the interval adjusting member 23 may also be arranged on the outer portion of the cathode block 10 .
  • each of the collector bars 21 and 22 is adjusted according to the position of the collector bars 21 and 22 in the length direction. and the cathode block 10 can be adjusted to change the contact pressure.
  • the contact pressure between each of the collector bars 21 and 22 and the cathode block 10 is higher at the center side of the cathode block 10 than at the end side of the cathode block 10 in the longitudinal direction of the collector bars 21 and 22.
  • the contact resistance on the end side of the cathode block 10 is higher than that on the center side of the cathode block 10 in the longitudinal direction of the collector bars 21 and 22 .
  • the cathode assembly 100 according to the first embodiment of the present invention has been described above. According to this embodiment, the connection work between the cathode block and the collector bar can be simplified.
  • the cathode assembly 100 has two collector bar units 20 . That is, the case where two collector bar units 20 are connected to one cathode block 10 has been described. However, the number of collector bar units 20 connected to the cathode block 10 may be one, or three or more. Further, in the above embodiment, the case where the collector bar units 20 are inserted from both sides of the cathode block 10 has been described, but the collector bar units 20 may be arranged so as to pass through the cathode block 10 .
  • Cathode assemblies according to the second and third embodiments described below differ from the cathode assembly 100 (FIG. 2) only in the configuration of the collector bar unit. Specifically, the cathode assemblies according to the second and third embodiments have a collector bar unit 30 (FIG. 5) and a collector bar unit 50 (FIG. 6) instead of the collector bar unit 20 (FIG. 4). I have it.
  • FIG. 5 is an exploded perspective view schematically showing the configuration of the collector bar unit 30 included in the cathode assembly according to the second embodiment of the invention.
  • the collector bar unit 30 includes a collector bar 31 , a collector bar 32 and a plurality of interval adjusting members 33 .
  • the interval adjusting member 33 has a threaded portion 33a.
  • the collector bar 31 is formed with a threaded hole 31a to be fastened with the threaded portion 33a.
  • the collector bar 32 is formed with a threaded hole 32a to be fastened with the threaded portion 33a.
  • Other configurations of collector bar 31 and collector bar 32 are similar to collector bar 21 and collector bar 22 (FIG. 4).
  • the spacing adjustment member 23 (FIG. 4) of the collector bar unit 20 has threaded portions at both ends, but the spacing adjustment member 33 has a threaded portion 33a at only one end.
  • the threaded portion 33a is fastened to one of the screw holes (threaded hole 31a or threaded hole 32a) of the collector bar 31 and the collector bar 32, and the end of the side where the threaded portion 33a is not formed is brought into contact with the other.
  • the interval between the collector bar 31 and the collector bar 32 is adjusted by bringing them into contact with each other.
  • the contact resistance between the collector bar and the cathode block can be adjusted as in the first embodiment. This simplifies the connection work between the cathode block and the collector bar.
  • FIG. 5 shows the case where the screw holes 31a and the screw holes 32a are alternately arranged along the length direction of the collector bars 31 and the collector bars 32, the screw holes 31a and the screw holes 32a are arranged. Any method can be used. For example, only the screw hole 32a may be arranged without arranging the screw hole 31a.
  • FIG. 6 is an exploded perspective view schematically showing the configuration of a collector bar unit 50 included in a cathode assembly according to a third embodiment of the invention. 6 is a view of the collector bar unit 50 viewed from the bottom side of the cathode block, unlike FIGS. 4 and 5. FIG.
  • the collector bar unit 50 includes a collector bar 51, a collector bar 52, and a plurality of interval adjusting members 53.
  • the collector bar 51 and the collector bar 52 are formed with semi-cylindrical grooves 51a and 52a that form cylindrical depressions when the collector bars 51 and 52 are arranged side by side.
  • the interval adjusting member 53 is arranged in a recess formed by the grooves 51a and 52a.
  • Other configurations of collector bar 51 and collector bar 52 are similar to collector bar 21 and collector bar 22 (FIG. 4).
  • FIG. 7 is a cross-sectional view schematically showing the configuration of the interval adjusting member 53.
  • the interval adjusting member 53 has a bolt 531 , a sleeve 532 and a base 533 .
  • the base 533 is formed with a screw hole 533a to be fastened with the bolt 531.
  • the base 533 has a tapered shape in which the outer diameter increases with increasing distance from the surface in which the screw hole 533a is formed.
  • the sleeve 532 has a cylindrical shape and is arranged between the head of the bolt 531 and the base 533 so as to surround the shaft of the bolt 531 .
  • the sleeve 532 is formed with a slit 532a (FIG. 6) open at the end on the base 533 side.
  • the sleeve 532 When the bolt 531 is tightened into the screw hole 533a of the base 533, the sleeve 532 is pushed by the head of the bolt 531 and moves to the base 533 side. At this time, since the base 533 has a tapered shape, the sleeve 532 receives stress in the direction of spreading outward. This stress widens the slit 532a and causes the lower end of the sleeve 532 to spread outward.
  • the spacing adjusting member 53 is arranged in a recess formed by the grooves 51a and 52a.
  • the sleeve 532 spreads outward, it pushes the gap between the collector bars 51 and 52 to widen.
  • the gap between the collector bar 51 and the collector bar 52 can be widened.
  • the interval between the collector bar 51 and the collector bar 52 can be adjusted by adjusting the degree of tightening of the bolt 531 .
  • the contact resistance between the collector bar and the cathode block can be adjusted as in the first embodiment. This simplifies the connection work between the cathode block and the collector bar.
  • the gap adjusting member 53 may have a structure in which the outer diameter is increased by some operation.
  • the structure instead of tightening the bolt, the structure may be such that the outer diameter is increased by tightening the nut.
  • the spacing adjusting member may have various specific structures as long as the spacing between the two collector bars can be adjusted by a screw mechanism.
  • the gap adjusting member includes a mechanism that adjusts the gap between the two collector bars with a screw.
  • a screw mechanism allows finer adjustment of the contact pressure between each of the two collector bars and the cathode block.
  • the cathode assembly according to the fourth embodiment of the present invention also differs from the cathode assembly 100 (FIG. 2) only in the configuration of the collector bar unit.
  • the collector bar unit of the cathode assembly according to the present embodiment further includes a conductive member made of a metal having a higher conductivity than the collector bars 21 and 22 in addition to the configuration of the collector bar unit 20 (FIG. 3).
  • the conductive member is, for example, a member made of copper.
  • the collector bar unit 20A of FIG. 8 further includes a conductive member 24 in addition to the configuration of the collector bar unit 20 (FIG. 3).
  • a conductive member 24 is arranged between the upper surfaces of the collector bars 21 and 22 and the bottom surface of the groove 10a.
  • the conductive member 24 may be arranged all over the direction in which the groove 10a extends, or may be intermittently arranged.
  • a collector bar unit 20B in FIG. 9 further includes a conductive member 25 in addition to the configuration of the collector bar unit 20 (FIG. 3).
  • the conductive member 25 is arranged on the surface of each of the collector bars 21 and 22 on the side where the collector bars 21 and 22 face each other.
  • a collector bar unit 20C in FIG. 10 further includes a conductive member 26 in addition to the configuration of the collector bar unit 20 (FIG. 3).
  • the conductive member 26 is embedded inside the collector bar 21 and the collector bar 22 .
  • CVD Cathode Voltage Drop
  • a conductive member made of a metal having higher conductivity than the collector bars 21 and 22 in the collector bar unit can be reduced by further including a conductive member made of a metal having higher conductivity than the collector bars 21 and 22 in the collector bar unit.
  • the methods of arranging the conductive members shown in FIGS. 8 to 10 are examples, and the method of arranging the conductive members is not limited to these. Further, in the above-described embodiment, the configuration in which the collector bar unit 20 further includes a conductive member based on the collector bar unit 20 described in the first embodiment has been described. It is also possible to combine a conductive member with the collector bar unit.
  • the cathode assembly according to the fifth embodiment of the present invention differs from the cathode assemblies according to the first to fourth embodiments in the shape of the collector bars included in the collector bar unit. Specifically, each of the collector bars of the cathode assembly according to this embodiment is provided with protrusions on its surface.
  • FIG. 11 is a perspective view schematically showing the configuration of a collector bar 21A, which is an example of the collector bar included in the cathode assembly according to this embodiment.
  • a plurality of dot-shaped protrusions 21Aa are provided on the upper surface of the collector bar 21A.
  • the protrusion 21Aa may be formed by cutting the collector bar, or may be formed by welding another metal part to the collector bar.
  • the protrusions 21Aa are preferably provided only on the inner side of the cathode block when the collector bar unit is inserted into the groove of the cathode block, although the projection 21Aa is not limited to this.
  • the load of the cathode block 10 (Fig. 1), the load of the melt 94 and the aluminum 95 are applied to the collector bar 21A.
  • the protrusions 21Aa By providing the protrusions 21Aa, the contact area between the collector bar 21A and the cathode block 10 is reduced. As a result, the contact pressure is increased, and the contact resistance between the collector bar 21A and the cathode block 10 can be reduced.
  • the conductive member 24 (FIG. 9) is arranged between the upper surface of the collector bar 21A and the bottom surface of the groove 10a, the contact resistance between the collector bar 21A and the conductive member 24 can be reduced.
  • FIG. 12 is a perspective view schematically showing the configuration of a collector bar 21B, which is another example of the collector bar included in the cathode assembly according to this embodiment.
  • a plurality of linear protrusions 21Ba are provided on the upper surface of the collector bar 21B.
  • the structure of the collector bar 21B also reduces the contact resistance between the collector bar 21B and the cathode block 10 (FIG. 1) or the contact resistance between the collector bar 21B and the conductive member 24 (FIG. 8). can be made smaller.
  • the shape and arrangement of the projections 21Aa and 21Ba shown in FIGS. 11 and 12 are examples, and the shape and arrangement of the projections are not limited to these.
  • FIG. 13 is a cross-sectional view schematically showing the construction of a cathode assembly 101 according to a sixth embodiment of the invention.
  • Cathode assembly 101 differs in cathode block size compared to cathode assembly 100 (FIG. 3).
  • Cathode assembly 101 includes cathode block 11 instead of cathode block 10 (FIG. 3) of cathode assembly 100 .
  • FIG. 14 is a cross-sectional view schematically showing the configuration of a cathode assembly 900, which is an example of a cathode assembly having a double-slot type cathode block.
  • Cathode assembly 900 comprises a cathode block 910 and two collector bars 920 . Two grooves 910a are formed in the cathode block 910, and a collector bar 920 is inserted into each of the grooves 910a.
  • the cathode block 11 of the cathode assembly 101 (Fig. 13) has one wide groove 11a instead of the two grooves 910a of the cathode block 910 (Fig. 14).
  • the collector bar unit 20 is inserted into this groove 11a.
  • a gap is formed between the collector bar 21 and the collector bar 22 in the collector bar unit 20 . Therefore, when the cross-sectional area of the groove of the cathode block is constant, the cross-sectional area of the entire collector bar is slightly smaller than when a single collector bar is arranged. On the other hand, when replacing a cathode assembly with a double-slot type cathode block, as shown in FIGS. Even if a gap is provided between them, the cross-sectional area of the entire collector bar is not reduced. It is also possible to make the cross-sectional area of the entire collector bar larger than before replacement. This makes it possible to reduce CVD.
  • FIG. 15 is a cross-sectional view schematically showing the construction of a cathode assembly 102 according to a seventh embodiment of the invention.
  • Cathode assembly 102 includes, in addition to the configuration of cathode assembly 100 (FIG. 3), filler material 61 disposed between collector bars 21 and 22, and two collector bars 21 and 22 each with A spacer 62 is arranged between the filler 61 .
  • the filler 61 may or may not be conductive.
  • the filler 61 is, for example, cement such as alumina cement, ramming paste, ceramics, steel shot, coke grains, or the like.
  • the spacer 62 is a thermoplastic resin or a metal or alloy with a melting point of 700°C or less.
  • a metal having a melting point of 700° C. or lower is, for example, aluminum.
  • the spacer is more preferably sheet-shaped. Spacer 62 may or may not be electrically conductive. Spacer 62 is preferably a thermoplastic resin.
  • Spacer 62 is preferably positioned between each of collector bar 21 and collector bar 22 and filler 61 , but is positioned only between one of collector bar 21 and collector bar 22 and filler 61 . may be That is, the spacer 62 may be arranged between at least one of the collector bar 21 and the collector bar 22 and the filler 61 .
  • the cathode assembly 102 is heated to a high temperature (eg 960°C) during operation. Thermal expansion of the collector bars 21 and 22 may deform the gap adjusting member 23 . According to this embodiment, the contact pressure at high temperatures can be maintained by filling the gap between the collector bars 21 and 22 with the filler 61 to increase the strength.
  • a high temperature eg 960°C
  • the spacers 62 by arranging the spacers 62, the stress due to the thermal expansion of the collector bars 21 and 22 can be alleviated, and damage to the cathode block 10 can be suppressed. Furthermore, the softening of the spacer 62 can moderate the change in contact pressure during temperature rise.
  • FIG. 16 is a cross-sectional view schematically showing the configuration of a testing device 70 used for this measurement. A photograph of the test device 70 is shown in FIG.
  • Parts 71 and 72 in FIG. 16 are iron cylinders corresponding to collector bar 21 and collector bar 22 in FIG. 15, respectively.
  • the part 73 is a part corresponding to the interval adjusting member 23, and has threaded portions at both ends like the interval adjusting member 23.
  • Part 74 is alumina cement corresponding to filler 61 and part 75 is a sheet of thermoplastic resin corresponding to spacer 62 .
  • the parts 71 and 72 are fixed so that the distance D between the upper end 71a of the part 71 and the lower end 72a of the part 72 is constant.
  • Aluminous cement was filled between two parts 75 to form part 74 while part 73 was manipulated to apply a preload of about 20 kN to parts 71 and 72 .
  • the parts 71 and 72 were heated by a heating device (not shown), and changes in load due to thermal expansion of the parts 71 and 72 were measured.
  • Fig. 18 is a graph showing the relationship between temperature and load obtained by this test. After the load increased from the initial 20 kN to about 30 kN from room temperature to about 100°C, the load was maintained at around 30 kN until about 400°C. It is considered that the reason why the load drops once near 100° C. is that the thermoplastic resin component 75 softens in this temperature range. In addition, the fact that the load temporarily decreased around 250° C. is considered to be due to the softening of the iron parts 71 and 72 in this temperature range. As a result, the load is stabilized around 30 kN between about 100° C. and about 400° C., and fluctuations are small.
  • the contact resistance increases due to thermal expansion when the temperature rises. Fluctuations can be suppressed.
  • a predetermined level for example, 2 N/mm 2
  • fluctuations in contact pressure can be reduced.
  • electrolytic furnaces 100, 101, 102, 900 cathode assemblies 10, 11, 910 cathode blocks 10a, 11a, 910a grooves 20, 20A, 20B, 20C, 30, 50 collector bar units 21, 22, 31, 32, 51, 52 , 21A, 22A, 920 collector bars 23, 33, 43, 53 spacing adjustment member 61 filler 62 spacers 24, 25, 26 conductive member 91 anode 92 shell 93 lining 94 melt 95 aluminum

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Electrolytic Production Of Metals (AREA)

Abstract

L'invention fournit un ensemble cathode qui permet de faciliter une opération de connexion entre un bloc cathodique et des barres collectrices. Cet ensemble cathode (100) est mis en œuvre dans un four électrolytique pour fusion d'aluminium, et est équipé d'un bloc cathodique (10) en carbone dans lequel est agencée une rainure (10a), et d'une unité de barres collectrices (20) insérée dans la rainure (10a). L'unité de barres collectrices (20) contient : deux barres collectrices (21, 22) en métal qui présentent chacune une forme se prolongeant dans la même direction que la rainure (10a), et qui sont disposées rangées dans la direction largeur de la rainure (10a) ; et un élément ajustement d'intervalle (23) ajustant l'intervalle entre les deux barres collectrices (21, 22). L'élément ajustement d'intervalle (23) contient un mécanisme ajustant l'intervalle entre les deux barres collectrices (21, 22) au moyen d'une vis.
PCT/JP2022/038136 2021-12-23 2022-10-13 Ensemble cathode WO2023119802A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2021209593 2021-12-23
JP2021-209593 2021-12-23

Publications (1)

Publication Number Publication Date
WO2023119802A1 true WO2023119802A1 (fr) 2023-06-29

Family

ID=86901949

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2022/038136 WO2023119802A1 (fr) 2021-12-23 2022-10-13 Ensemble cathode

Country Status (1)

Country Link
WO (1) WO2023119802A1 (fr)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130319853A1 (en) * 2011-02-11 2013-12-05 Sgl Carbon Se Cathode configuration, cathode block with a groove, and production method
US20160208399A1 (en) * 2013-12-16 2016-07-21 Hatch Ltd. Low resistance electrode assemblies for production of metals
JP2017222914A (ja) * 2016-06-16 2017-12-21 Ｓｅｃカーボン株式会社 カソード

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130319853A1 (en) * 2011-02-11 2013-12-05 Sgl Carbon Se Cathode configuration, cathode block with a groove, and production method
US20160208399A1 (en) * 2013-12-16 2016-07-21 Hatch Ltd. Low resistance electrode assemblies for production of metals
JP2017222914A (ja) * 2016-06-16 2017-12-21 Ｓｅｃカーボン株式会社 カソード

Similar Documents

Publication Publication Date Title
CA2914511C (fr) Ensembles d'electrode basse resistance destines a la production de metaux
AU2015348020B2 (en) Cathode current collector for a hall-heroult cell
CA3027826C (fr) Cathode
US1757695A (en) Electrode
WO2023119802A1 (fr) Ensemble cathode
WO2003014423A1 (fr) Barre de cathode collectrice a trois elements
CN109863258B (zh) 用于霍尔-埃鲁电池的阴极集流器/连接器
AU2019235250B2 (en) Cathode elements for a Hall-Heroult cell for aluminium production and a cell of this type having such elements installed
US4462104A (en) Electrode holder for electric arc furnaces
EP0142476A2 (fr) Electrode composite précuite en carbone pour four à arc électrique
US3595977A (en) Self-baking electrodes for electric arc furnaces
WO2023119772A1 (fr) Ensemble électrode
CA1198760A (fr) Porte-electrodes pour fours a arc
CA2457363C (fr) Barre de cathode collectrice a trois elements
EP0096938B1 (fr) Electrodes pour fours de verre
EP4139502B1 (fr) Ensemble cathode pour une cellule hall-heroult pour la production d'aluminium
JP2962150B2 (ja) 直流アーク炉用炉底電極
RU2285356C2 (ru) Подовый электрод электропечи
JP2624419B2 (ja) 直流アーク炉の給電方法
JP2717848B2 (ja) 焼成炭素電極の黒鉛化方法
CA2470742A1 (fr) Procede de production de blocs cathodiques

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22910528

Country of ref document: EP

Kind code of ref document: A1