US20240003031A1 - Controlling electrode current density of an electrolytic cell - Google Patents
Controlling electrode current density of an electrolytic cell Download PDFInfo
- Publication number
- US20240003031A1 US20240003031A1 US18/038,804 US202118038804A US2024003031A1 US 20240003031 A1 US20240003031 A1 US 20240003031A1 US 202118038804 A US202118038804 A US 202118038804A US 2024003031 A1 US2024003031 A1 US 2024003031A1
- Authority
- US
- United States
- Prior art keywords
- electrode plate
- region
- aco
- electrode
- width
- 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.)
- Pending
Links
- 229910052751 metal Inorganic materials 0.000 claims abstract description 28
- 239000002184 metal Substances 0.000 claims abstract description 28
- 238000000034 method Methods 0.000 claims abstract description 26
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 21
- 238000004519 manufacturing process Methods 0.000 claims abstract description 21
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 16
- 230000007704 transition Effects 0.000 claims description 13
- 230000007423 decrease Effects 0.000 claims description 6
- 239000007788 liquid Substances 0.000 claims description 4
- 230000003247 decreasing effect Effects 0.000 claims description 3
- 238000005868 electrolysis reaction Methods 0.000 claims description 3
- 238000005265 energy consumption Methods 0.000 abstract description 6
- 230000020169 heat generation Effects 0.000 abstract description 3
- 238000005516 engineering process Methods 0.000 abstract description 2
- 239000004411 aluminium Substances 0.000 abstract 1
- 239000003792 electrolyte Substances 0.000 description 10
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 5
- 230000000977 initiatory effect Effects 0.000 description 5
- 239000000463 material Substances 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 229910002092 carbon dioxide Inorganic materials 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- QYEXBYZXHDUPRC-UHFFFAOYSA-N B#[Ti]#B Chemical compound B#[Ti]#B QYEXBYZXHDUPRC-UHFFFAOYSA-N 0.000 description 2
- 229910033181 TiB2 Inorganic materials 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 239000010405 anode material Substances 0.000 description 2
- 239000001569 carbon dioxide Substances 0.000 description 2
- 239000010406 cathode material Substances 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 238000004513 sizing Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 239000004155 Chlorine dioxide Substances 0.000 description 1
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000003575 carbonaceous material Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- OSVXSBDYLRYLIG-UHFFFAOYSA-N chlorine dioxide Inorganic materials O=Cl=O OSVXSBDYLRYLIG-UHFFFAOYSA-N 0.000 description 1
- 230000002860 competitive effect Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 229910001610 cryolite Inorganic materials 0.000 description 1
- 229910001882 dioxygen Inorganic materials 0.000 description 1
- 239000007792 gaseous phase Substances 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 229910001338 liquidmetal Inorganic materials 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- RCKBMGHMPOIFND-UHFFFAOYSA-N sulfanylidene(sulfanylidenegallanylsulfanyl)gallane Chemical compound S=[Ga]S[Ga]=S RCKBMGHMPOIFND-UHFFFAOYSA-N 0.000 description 1
- 238000005382 thermal cycling Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
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
- C25C7/00—Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells
- C25C7/02—Electrodes; Connections thereof
-
- 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
- C25C3/12—Anodes
-
- 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
- C25C7/005—Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells of cells for the electrolysis of melts
Definitions
- the present application generally relates to an apparatus and method for the electrolytic production of a metal.
- the apparatus and method are adapted for the production of a metal, such as aluminum, using vertical electrodes of inert or oxygen-evolving anodes and cathode plates.
- An electrolytic cell for the production of aluminum or other metals comprises alternating rows of inert anodes and wettable inert cathodes in the shape of flat plates, immersed in a molten salt bath with sufficient ionic conductivity to pass current.
- the molten salt bath has the capacity to dissolve a compound of the metal to be reduced (e.g. a metal oxide, chloride, carbonate, etc.).
- Gas, such as oxygen, chlorine or carbon dioxide, is produced on the anodes and exits the cell as an offgas.
- Liquid metal is produced on the cathode plates and runs down in a thin film by gravity into a pool or sump for collection.
- the anodes and cathode plates are separated by a distance, known as the anode-cathode distance (ACD), and have an overlapping dimension, known as anode-cathode overlapping (ACO).
- ACD anode-cathode distance
- ACO anode-cathode overlapping
- Cathodes are electrically conductive cathode plates, chemically resistant to metal and electrolyte, and have good wettability for the produced metal.
- the optimum shape and size of the cathode plates is related to the desired cell resistance, current density, anode dimensions and cell dimensions.
- an electrode plate for the electrolytic production of a metal using an electrolytic cell comprising a plurality of said electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows of said anode and cathode plates.
- the electrode plate defines: a connecting region adjacent a first end of the electrode plate for connecting the electrode plate to the electrolytic cell; a middle region extending from the connecting region without overlapping adjacent electrode plates; and an anode-cathode overlapping (ACO) region extending from the middle region to a second end of the electrode plate opposite to the first end, and configured for overlapping adjacent electrode plate(s); wherein the electrode plate comprises two opposite surfaces for facing surfaces of electrode plates of adjacent rows; and wherein a ratio of the ACO region's surface area to the middle region's surface area is superior to one in order to maximize current density in the ACO region.
- the ACO/middle surface ratio is equal or superior to 2.
- the electrode plate may have a rectangular shape, wherein a width of the electrode plate is constant from the ACO region to the middle and connecting regions.
- an electrode plate for the electrolytic production of a metal using an electrolysis cell comprising a plurality of said electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows of said anode and cathode plates, the electrode plate defining: a connecting region adjacent a first end of the electrode plate for connecting the electrode plate to the electrolytic cell; a middle region extending from the connecting region without overlapping adjacent electrode(s); and an ACO region extending from the middle region and configured for overlapping adjacent electrodes(s); wherein an average cross-sectional area ratio of the ACO region to the middle and connecting regions is superior to one in order to maximize current density in the ACO region while retaining a mechanical strength of the connecting region for supporting the electrode plate.
- the average ACO/middle cross-sectional area ratio is equal or superior to 2.
- the electrode plate may have a goal post shape wherein the middle and connecting regions define a pair of legs on either side thereof, with a central gap between the legs below the ACO region.
- the electrode plate may have a paddle shape, wherein the ACO region has a first width, the middle and connecting regions have a second width, the second width being inferior to the first width.
- the electrode plate may have a trapezoid shape wherein a width of the electrode plate constantly decreases from the second end to the first end of the electrode plate.
- the ACO region and the middle region of the electrode plate has a trapezoid shape with a width of the electrode plate constantly decreases from the second end of the electrode plate to a junction between the middle and connecting regions, the connecting region having a rectangular shape.
- a surrounding edge of the surfaces has round transitions between the first end of the plate and the connecting region, and/or the surrounding edge has round transitions between the second end the ACO region.
- the electrode plate comprises two opposite surfaces for facing surfaces of electrode plates of adjacent rows, and a surrounding edge of the surfaces which has round transitions between the first end of the plate and the connecting region, and/or the surrounding edge has round transitions between the second end the ACO region.
- the metal to produce is aluminum, the electrode plate being wettable by liquid aluminum metal.
- the electrode plate is a cathode plate.
- an electrolytic cell for the electrolytic production of a metal comprising one or more electrode plates as disclosed herein.
- the metal is aluminum.
- a method for controlling the current density of a plurality of electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows in an electrolytic cell the electrode plate defining: a connecting region for connecting the electrode plate to the electrolytic cell; a middle region extending from the connecting region without overlapping adjacent electrode(s); and an ACO region extending from the middle region and configured for overlapping adjacent electrodes(s); wherein each electrode plate comprises a surface for facing another electrode plate of the adjacent row; the method comprising the step of: maximizing current density in the ACO region by varying a ratio of the ACO region's surface area to the middle region's surface area such as the ACO/middle surface area ratio is superior to one.
- a method for controlling the current density of a plurality of electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows in an electrolytic cell the electrode plate defining: a connecting region for connecting the electrode plate to the electrolytic cell; an middle region extending from the connecting region without overlapping adjacent electrode(s); and an ACO region extending from the middle region and configured for overlapping adjacent electrodes(s); the method comprising the step of: providing electrode plates in which an average cross-sectional area ratio of the ACO region to the middle and connecting regions is superior to one in order to maximize current density in the ACO region while retaining a mechanical strength of the connecting region for supporting the electrode plate.
- a method for maximizing the current density of an electrolytic cell comprising a plurality of electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows in an electrolytic cell, the method comprising the steps of: replacing each of existing electrodes plates of the cell by the electrodes plate as disclosed herein.
- the electrode plates in particular the cathodes plates, as disclosed herein allows:
- the electrode plates in particular cathodes plates, as disclosed herein, can be used for the manufacturing of new electrolytic cells, but also for replacing electrodes of existing electrolytic cells, in order to reduce the energy (e.g. electricity) consumption, providing as such an environmentally friendly process for metal production, in particular aluminum production, more preferably when the cathodes plates as disclosed herein are used conjointly with inert—oxygen evolving anodes.
- FIG. 1 A is a partially schematic cross-sectional view of an electrolytic cell known in the art
- FIG. 1 B is a side view of a portion of interleaved anode and cathode modules known in the art
- FIG. 2 A is a schematic view of an electrode plate in accordance with a first embodiment of the present disclosure
- FIG. 2 B is a schematic view of an electrode plate in accordance with a second embodiment of the present disclosure.
- FIG. 2 C is a schematic view of an electrode plate in accordance with a third embodiment of the present disclosure.
- FIG. 2 D is a schematic view of an electrode plate in accordance with a fourth embodiment of the present disclosure.
- FIG. 3 is a front view of an electrode plate in accordance with a fifth embodiment of the present disclosure.
- FIG. 4 illustrates a method for controlling the current density of a plurality of electrodes plates in accordance with a preferred embodiment of the present disclosure
- FIG. 5 illustrates a method for controlling the current density of a plurality of electrodes plates in accordance with another preferred embodiment of the present disclosure.
- FIG. 6 illustrates a method for maximizing the current density of an electrolytic cell comprising a plurality of electrodes plates in accordance with a preferred embodiment of the present disclosure.
- weight % wt. %
- time, voltage, resistance, volume or temperature can vary within a certain range depending on the margin of error of the method or device used to evaluate such weight %, time, voltage, resistance, volume or temperature.
- a margin of error of 10% is generally accepted.
- the invention as disclosed herein is directed to a new configuration of an electrolytic cell, in particular the electrodes plates, for increasing the current density.
- cathode and anode plates are arranged in parallel, alternating rows as illustrated on FIGS. 1 A and 1 B from U.S. Pat. No. 10,415,147 (LIU Xinghua), the content of which is incorporated herein by reference.
- FIG. 1 A shows a schematic cross-section of an electrolytic cell 10 for producing a metal (e.g. aluminum) by the electrochemical reduction of an electrolyte (e.g. alumina dissolved in molten cryolite) using an anode and a cathode.
- the cell 10 has at least one anode module 12 comprising a plurality of vertically oriented anodes 12 E suspended above at least one cathode module 14 having a plurality of vertically oriented cathodes 14 E positioned in a cell reservoir 16 .
- the vertical cathodes 14 E extend upwards towards the anode module 12 . While a plurality of anodes 12 E and cathodes 14 E of a specific number are shown FIGS.
- any number of anodes 12 E and cathodes 14 E greater than or equal to 1 may be used to define an anode module 12 or a cathode module 14 , respectively.
- the cathode module 14 is fixedly coupled to the bottom of the cell 10 with the cathodes 14 E supported in a cathode support 14 B which rests in the cell reservoir 16 on cathode blocks 18 , e.g., made from carbonaceous material in electrical continuity with one or more cathode current collector bars 20 .
- the cathode blocks 18 may be fixedly coupled to the bottom of the cell 10 .
- the reservoir 16 may has a steel shell 16 S and be lined with insulating material 16 A, refractory material 16 B and sidewall material 16 C.
- the reservoir 16 is capable of retaining a bath of molten electrolyte (shown by dashed line 22 ) and a molten aluminum metal pad therein.
- Portions of an anode bus 24 that supplies electrical current to the anode modules 12 are shown pressed into electrical contact with anode rods 12 L of the anode modules 12 .
- the anode rods 12 L are structurally and electrically connected to an anode distribution plate 12 S, to which a thermal insulation layer 12 B is attached.
- the anodes 12 E extend through the thermal insulation layer 12 B and mechanically and electrically contact the anode distribution plate 12 S.
- the anode bus 24 would conduct direct electrical current from a suitable source 26 through the anode rods 12 L, the anode distribution plate 12 S, anode elements, electrolyte 22 to the cathodes 14 E and from there through the cathode support 14 B, cathode blocks 18 and cathode current collector bars 20 to the other pole of the source of electricity 26 .
- the anodes 12 E of each anode module 12 are in electrical continuity.
- the cathodes 14 E of each cathode module 14 are in electrical continuity.
- FIG. 1 B shows the anode module 12 and the cathode module 14 with their electrodes 12 E and 14 E in an interleaved relationship.
- the height of the bath 22 relative to the cathodes 14 may be called the “bath-to cathode distance” or BCD.
- the anode module 12 can be raised and lowered (i.e. selectively positionable) in height relative to the position of the cathode module 14 , as indicated by double ended arrow V.
- the anodes 12 E are not completely submerged in the bath and extend across the bath-vapor interface 22 during metal production. This vertical adjustability allows the “overlap” Y of the anodes 12 E and the cathodes 14 E to be adjusted.
- the level of the electrolytic bath 22 , the height of the anodes 12 E and the cathodes 14 E may require the adjustment of the anode module 12 position relative to the cathode module 14 in the vertical direction, to achieve a selected anode-cathode overlap (ACO) Y, as well as depth of submersion in the electrolyte 22 .
- ACO anode-cathode overlap
- the anodes 12 E are at least partially immersed in the electrolyte and the cathode electrodes 14 E are completely immersed in the electrolyte.
- Changing the ACO Y can be used to change the cell resistance and maintain stable cell temperature.
- the opposed, vertically oriented electrodes 12 E, 14 E permit the gaseous phases (O 2 ) generated proximal thereto to detach therefrom and physically disassociate from the anodes 12 E due to the buoyancy of the O 2 gas bubbles in the molten electrolyte. Since the bubbles are free to escape from the surfaces of the anode 12 , they do not build up on the anode surfaces to form an electrically insulative/resistive layer allowing the build-up of electrical potential, resulting in high resistance and, high energy consumption.
- the anodes 12 E may be arranged in rows or columns with or without a side-to side clearance or gap between them to create a channel that enhances molten electrolyte movement, thereby improving mass transport and allowing dissolved alumina to reach the surfaces of the anode module 12 .
- the number of rows of anodes 12 E can vary from 1 to any selected number and the number of anodes 12 E in a row can vary from 1 to any number.
- the cathodes 14 E may be similarly arranged in rows with or without side-to-side clearance (gaps) between them and may similarly vary in the number of rows and the number of cathodes 14 E in a row from 1 to any number.
- FIGS. 1 A and 1 B The shapes of both vertical anodes and cathodes illustrated on FIGS. 1 A and 1 B are generally plate shaped. Most commonly, the plates are thin and rectangular in shape. More complicated shapes, which may include sharp angles and rapidly changing cross sections can be locations of crack initiation, especially during thermal cycling periods.
- New electrode shapes have then been developed and are described herein below in reference to FIGS. 2 A-D and 3 .
- the electrode plates 100 , 200 , 300 , 400 may define three regions:
- This decrease in current density is achieved by developing proprietary anode and cathode plate materials that are dimensionally stable.
- the cathode plate is preferably wettable by liquid aluminum metal. These proprietary materials are then arranged in the vertical configuration as disclosed herein that allows retaining the same current per square foot of building space at a lower current density at the active surfaces.
- Minimizing the middle region 120 minimizes the impact on cell resistance and energy efficiency, since there is little amount of current in this region.
- Another approach consists in decreasing the middle region 120 of the electrode plate 100 as far as its mechanical strength and stability allow.
- the ratio of cross-sectional area at the top of the electrode plate to the cross-sectional area at the bottom of the electrode plate should be superior to 1, more preferably equal or superior to 2.
- the electrode plate 100 has a straight rectangular shape in which the average cross-sectional area ratio of the ACO region to the middle or to the lower region is 1 (one).
- the surface ratio between the ACO and middle areas can be modulated or tuned by varying the ACO region in order to have a surface ratio superior to 1.
- FIG. 2 B , FIG. 2 C and FIG. 2 D illustrate more complex shapes with a larger area of the electrode plates in regions of high current density and a smaller area in regions of low current density.
- FIG. 2 B illustrates an electrode plate 200 having a goal post shape with a pair of narrow legs 210 on either side with a gap 220 in the middle and connecting regions 120 , 130 below the ACO region 110 .
- FIG. 2 C illustrates an electrode plate 300 having a paddle shape wider in the ACO region 110 and narrower in the middle/connecting regions 120 , 130 .
- FIG. 2 D illustrates an electrode plate 400 having a trapezoidal shape, wherein the width of the electrode plate is continuously sizing down from the ACO region 110 to the middle region 120 and then to the connecting region 130 .
- the shape which results in the highest current density is the one that has the least area in the middle/connecting regions 120 , 130 below the ACO region 110 , such as with goal post shape 200 and the paddle shape 300 .
- the trapezoidal shape 400 of FIG. 2 D preferably combines the advantages of maximizing the metal produced in the upper ACO region 110 , with ease of manufacture (i.e., the parts can be made as net-shape without cut-outs) with lower manufacturing cost, adequate strength, and avoidance of abrupt changes in cross section or inside cuts, that be sources of crack initiation (i.e., no introduction of weak points or crack initiation sites).
- the electrode plates as defined herein, when used as a cathode plate can be made of titanium diboride (TiB 2 ) or zirconium diboride (ZrB 2 ). Any material that is electrically conductive, resistant to molten metal and electrolyte, and wettable to a metal, such as aluminum, can be used without departing from the scope of the present disclosure.
- the method 1000 comprises the step of:
- the method 2000 comprises the step of:
- a method 3000 for maximizing the current density of an electrolytic cell comprising a plurality of electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows in an electrolytic cell.
- the method 3000 comprising the step of:
- FIG. 3 shows an example of an electrode plate 500 in accordance with a preferred embodiment of the present disclosure comprising as well an ACO region 110 , a connecting region 130 and a middle region 120 extending therebetween.
- the electrode plate 500 and the trapezoidal electrode plate 400 of FIG. 2 D differ in that the opposite edges 530 a , 530 b of the connecting region 130 of the plate 500 are parallel one to the other.
- the width of the electrode plate 500 is continuously sizing down from X 1 at the top end 510 of the ACO region 110 to X 2 at the bottom end 520 of the middle region 120 , the bottom 530 of the plate forming the connecting region 130 having a rectangular-like shape with the parallel edges 530 a , 530 b.
- the plate 500 may further have a round transition between the top end 510 and each of the two opposite edges 510 a , 510 b of the ACO region 110 , identified with the radius R 1 . Furthermore, the plate 500 may have a round transition between the bottom end 530 and each of the two opposite edges 530 a , 530 b of the connecting region 130 , identified with the radius R 2 . Such round transitions R 1 and/or R 2 allow avoiding to introduce weak points or crack initiation sites of the electrode plates 500 .
- Table 1 below provides some dimensions of the electrodes plates 500 illustrated on FIG. 3 , with L representing the total length of the electrode plate.
- the electrode plates as disclosed herein avoids the weaknesses discussed in accordance with the previous embodiments because there are no sharp geometry changes or narrow cross sections.
- the parts can be made into net shapes, without cut-outs, which can introduce flaws and crack initiation sites.
- the invention enables metal production with competitive energy efficiency.
- the invention also allows for less heat loss in the cathode plate(s).
Abstract
Apparatuses and methods for controlling electrode current density of an electrolytic cell during the electrolytic production of a metal, such as aluminum or aluminium, are disclosed. The cell has anodes and cathode plates vertically aligned and arranged in alternating rows. Each electrode defines a connecting region for connecting the electrode to the cell, a middle region, and an ACO (Anode-Cathode Overlap) region extending from the middle region for overlapping adjacent electrodes(s). The ratio of the ACO region's surface area to the middle region's surface area is superior to one. Alternatively, an average cross-sectional ACO region to the middle and connecting regions, is superior than one, preferably superior than 2. The present technology allows maximizing current density in the ACO region. Increasing these ratios has less impact on the environment by reducing heat generation and energy consumption, making the metal production eco-friendly, in particular when used with inert or oxygen-evolving electrodes.
Description
- The present patent application claims the benefits of priority of U.S. Provisional Patent Application No. 63/118,774 entitled “APPARATUS AND METHOD FOR CONTROLLING ELECTRODE CURRENT DENSITY OF AN ELECTROLYTIC CELL”, and filed at the United States Patent and Trademark Office on Nov. 27, 2020, the content of which is incorporated herein by reference.
- The present application generally relates to an apparatus and method for the electrolytic production of a metal. In particular, the apparatus and method are adapted for the production of a metal, such as aluminum, using vertical electrodes of inert or oxygen-evolving anodes and cathode plates.
- An electrolytic cell for the production of aluminum or other metals comprises alternating rows of inert anodes and wettable inert cathodes in the shape of flat plates, immersed in a molten salt bath with sufficient ionic conductivity to pass current. The molten salt bath has the capacity to dissolve a compound of the metal to be reduced (e.g. a metal oxide, chloride, carbonate, etc.). Gas, such as oxygen, chlorine or carbon dioxide, is produced on the anodes and exits the cell as an offgas. Liquid metal is produced on the cathode plates and runs down in a thin film by gravity into a pool or sump for collection. The anodes and cathode plates are separated by a distance, known as the anode-cathode distance (ACD), and have an overlapping dimension, known as anode-cathode overlapping (ACO).
- Cathodes are electrically conductive cathode plates, chemically resistant to metal and electrolyte, and have good wettability for the produced metal. The optimum shape and size of the cathode plates is related to the desired cell resistance, current density, anode dimensions and cell dimensions.
- It would be possible to simply reduce the width of each electrode plate to increase the current density everywhere. However, simply reducing the area of the electrode plates in all regions comes at a cost of increasing the cell resistance and specific energy consumption. This increases the heat generation and makes it more difficult or impossible to design a cell with the proper heat balance.
- There is thus a need for a new configuration or design of an electrolytic cell and method thereof for making a metal, such as aluminum, by increasing the current density of the electrodes.
- The shortcomings of the prior art are generally mitigated by a new apparatus and method for increasing current density of the electrodes during the electrolytic production of a metal, such as aluminum.
- Therefore, according to a first aspect, it is disclosed an electrode plate for the electrolytic production of a metal using an electrolytic cell comprising a plurality of said electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows of said anode and cathode plates. The electrode plate defines: a connecting region adjacent a first end of the electrode plate for connecting the electrode plate to the electrolytic cell; a middle region extending from the connecting region without overlapping adjacent electrode plates; and an anode-cathode overlapping (ACO) region extending from the middle region to a second end of the electrode plate opposite to the first end, and configured for overlapping adjacent electrode plate(s); wherein the electrode plate comprises two opposite surfaces for facing surfaces of electrode plates of adjacent rows; and wherein a ratio of the ACO region's surface area to the middle region's surface area is superior to one in order to maximize current density in the ACO region. Preferably, the ACO/middle surface ratio is equal or superior to 2.
- According to a preferred embodiment for the above first aspect, the electrode plate may have a rectangular shape, wherein a width of the electrode plate is constant from the ACO region to the middle and connecting regions.
- According to a second aspect, it is disclosed an electrode plate for the electrolytic production of a metal using an electrolysis cell comprising a plurality of said electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows of said anode and cathode plates, the electrode plate defining: a connecting region adjacent a first end of the electrode plate for connecting the electrode plate to the electrolytic cell; a middle region extending from the connecting region without overlapping adjacent electrode(s); and an ACO region extending from the middle region and configured for overlapping adjacent electrodes(s); wherein an average cross-sectional area ratio of the ACO region to the middle and connecting regions is superior to one in order to maximize current density in the ACO region while retaining a mechanical strength of the connecting region for supporting the electrode plate. Preferably, the average ACO/middle cross-sectional area ratio is equal or superior to 2.
- The following preferred embodiments apply for the first and second aspects disclosed above, unless otherwise stated.
- According to a preferred embodiment, the electrode plate may have a goal post shape wherein the middle and connecting regions define a pair of legs on either side thereof, with a central gap between the legs below the ACO region.
- According to a preferred embodiment, the electrode plate may have a paddle shape, wherein the ACO region has a first width, the middle and connecting regions have a second width, the second width being inferior to the first width.
- According to a preferred embodiment, the electrode plate may have a trapezoid shape wherein a width of the electrode plate constantly decreases from the second end to the first end of the electrode plate.
- According to a preferred embodiment, the ACO region and the middle region of the electrode plate has a trapezoid shape with a width of the electrode plate constantly decreases from the second end of the electrode plate to a junction between the middle and connecting regions, the connecting region having a rectangular shape.
- According to a preferred embodiment for the first aspect disclosed above, a surrounding edge of the surfaces has round transitions between the first end of the plate and the connecting region, and/or the surrounding edge has round transitions between the second end the ACO region.
- According to a preferred embodiment of the second aspect disclosed above, the electrode plate comprises two opposite surfaces for facing surfaces of electrode plates of adjacent rows, and a surrounding edge of the surfaces which has round transitions between the first end of the plate and the connecting region, and/or the surrounding edge has round transitions between the second end the ACO region.
- According to a preferred embodiment, the metal to produce is aluminum, the electrode plate being wettable by liquid aluminum metal.
- According to a preferred embodiment, the electrode plate is a cathode plate.
- According to a third aspect, it is disclosed an electrolytic cell for the electrolytic production of a metal comprising one or more electrode plates as disclosed herein. Preferably, the metal is aluminum.
- According to a third aspect, it is disclosed the use of the electrode plate as disclosed herein, or the electrolytic cell as disclosed herein, for manufacturing an electrolysis cell comprising a plurality of said electrode plate.
- According to a fourth aspect, it is disclosed the use of the electrode plate as disclosed herein, or the electrolytic cell as disclosed herein, for the electrolytic production of aluminum.
- According to a fifth aspect, it is disclosed a method for controlling the current density of a plurality of electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows in an electrolytic cell, the electrode plate defining: a connecting region for connecting the electrode plate to the electrolytic cell; a middle region extending from the connecting region without overlapping adjacent electrode(s); and an ACO region extending from the middle region and configured for overlapping adjacent electrodes(s); wherein each electrode plate comprises a surface for facing another electrode plate of the adjacent row; the method comprising the step of: maximizing current density in the ACO region by varying a ratio of the ACO region's surface area to the middle region's surface area such as the ACO/middle surface area ratio is superior to one.
- According to a sixth aspect, it is disclosed a method for controlling the current density of a plurality of electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows in an electrolytic cell, the electrode plate defining: a connecting region for connecting the electrode plate to the electrolytic cell; an middle region extending from the connecting region without overlapping adjacent electrode(s); and an ACO region extending from the middle region and configured for overlapping adjacent electrodes(s); the method comprising the step of: providing electrode plates in which an average cross-sectional area ratio of the ACO region to the middle and connecting regions is superior to one in order to maximize current density in the ACO region while retaining a mechanical strength of the connecting region for supporting the electrode plate.
- According to a seventh aspect, it is disclosed a method for maximizing the current density of an electrolytic cell comprising a plurality of electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows in an electrolytic cell, the method comprising the steps of: replacing each of existing electrodes plates of the cell by the electrodes plate as disclosed herein.
- The electrode plates, in particular the cathodes plates, as disclosed herein allows:
-
- increasing the ratios of the ACO region's surface area to the middle region's surface area by reducing the surface or average cross-sectional area of the lower current density regions below or above the ACO region providing less impact on heat generation and energy consumption; and/or
- having an average cross-sectional area ratio of the ACO region to the middle and connecting regions superior to one, preferably superior to two, in order to maximize current density in the ACO region while retaining a mechanical strength of the connecting region for supporting the electrode plates in the electrolytic cell.
- Furthermore, the electrode plates, in particular cathodes plates, as disclosed herein, can be used for the manufacturing of new electrolytic cells, but also for replacing electrodes of existing electrolytic cells, in order to reduce the energy (e.g. electricity) consumption, providing as such an environmentally friendly process for metal production, in particular aluminum production, more preferably when the cathodes plates as disclosed herein are used conjointly with inert—oxygen evolving anodes.
- The above and other aspects, features and advantages of the invention will become more readily apparent from the following description, reference being made to the accompanying drawings in which:
-
FIG. 1A is a partially schematic cross-sectional view of an electrolytic cell known in the art; -
FIG. 1B is a side view of a portion of interleaved anode and cathode modules known in the art; -
FIG. 2A is a schematic view of an electrode plate in accordance with a first embodiment of the present disclosure; -
FIG. 2B is a schematic view of an electrode plate in accordance with a second embodiment of the present disclosure; -
FIG. 2C is a schematic view of an electrode plate in accordance with a third embodiment of the present disclosure; -
FIG. 2D is a schematic view of an electrode plate in accordance with a fourth embodiment of the present disclosure; -
FIG. 3 is a front view of an electrode plate in accordance with a fifth embodiment of the present disclosure; -
FIG. 4 illustrates a method for controlling the current density of a plurality of electrodes plates in accordance with a preferred embodiment of the present disclosure; -
FIG. 5 illustrates a method for controlling the current density of a plurality of electrodes plates in accordance with another preferred embodiment of the present disclosure; and -
FIG. 6 illustrates a method for maximizing the current density of an electrolytic cell comprising a plurality of electrodes plates in accordance with a preferred embodiment of the present disclosure. - Novel apparatus and method will be described hereinafter. Although the invention is described in terms of specific illustrative embodiments, it is to be understood that the embodiments described herein are by way of example only and that the scope of the invention is not intended to be limited thereby.
- The terminology used herein is in accordance with definitions set out below.
- By “about”, it is meant that the value of weight % (wt. %), time, voltage, resistance, volume or temperature can vary within a certain range depending on the margin of error of the method or device used to evaluate such weight %, time, voltage, resistance, volume or temperature. A margin of error of 10% is generally accepted.
- The description which follows, and the embodiments described therein are provided by way of illustration of an example of particular embodiments of principles and aspects of the present invention. These examples are provided for the purposes of explanation and not of limitation, of those principles of the invention. In the description that follows, like parts and/or steps are marked throughout the specification and the drawing with the same respective reference numerals.
- As aforesaid, the invention as disclosed herein is directed to a new configuration of an electrolytic cell, in particular the electrodes plates, for increasing the current density.
- In vertical inert anode cells, cathode and anode plates are arranged in parallel, alternating rows as illustrated on
FIGS. 1A and 1B from U.S. Pat. No. 10,415,147 (LIU Xinghua), the content of which is incorporated herein by reference. -
FIG. 1A shows a schematic cross-section of anelectrolytic cell 10 for producing a metal (e.g. aluminum) by the electrochemical reduction of an electrolyte (e.g. alumina dissolved in molten cryolite) using an anode and a cathode. Thecell 10 has at least oneanode module 12 comprising a plurality of vertically orientedanodes 12E suspended above at least onecathode module 14 having a plurality of vertically orientedcathodes 14E positioned in acell reservoir 16. Thevertical cathodes 14E extend upwards towards theanode module 12. While a plurality ofanodes 12E andcathodes 14E of a specific number are shownFIGS. 1A and 1B , any number ofanodes 12E andcathodes 14E greater than or equal to 1 may be used to define ananode module 12 or acathode module 14, respectively. In some embodiments, thecathode module 14 is fixedly coupled to the bottom of thecell 10 with thecathodes 14E supported in acathode support 14B which rests in thecell reservoir 16 on cathode blocks 18, e.g., made from carbonaceous material in electrical continuity with one or more cathode current collector bars 20. The cathode blocks 18 may be fixedly coupled to the bottom of thecell 10. Thereservoir 16 may has asteel shell 16S and be lined with insulatingmaterial 16A,refractory material 16B andsidewall material 16C. Thereservoir 16 is capable of retaining a bath of molten electrolyte (shown by dashed line 22) and a molten aluminum metal pad therein. Portions of ananode bus 24 that supplies electrical current to theanode modules 12 are shown pressed into electrical contact withanode rods 12L of theanode modules 12. Theanode rods 12L are structurally and electrically connected to ananode distribution plate 12S, to which athermal insulation layer 12B is attached. Theanodes 12E extend through thethermal insulation layer 12B and mechanically and electrically contact theanode distribution plate 12S. Theanode bus 24 would conduct direct electrical current from asuitable source 26 through theanode rods 12L, theanode distribution plate 12S, anode elements,electrolyte 22 to thecathodes 14E and from there through thecathode support 14B, cathode blocks 18 and cathode current collector bars 20 to the other pole of the source ofelectricity 26. Theanodes 12E of eachanode module 12 are in electrical continuity. Similarly, thecathodes 14E of eachcathode module 14 are in electrical continuity. -
FIG. 1B shows theanode module 12 and thecathode module 14 with theirelectrodes bath 22 relative to thecathodes 14 may be called the “bath-to cathode distance” or BCD. Theanode module 12 can be raised and lowered (i.e. selectively positionable) in height relative to the position of thecathode module 14, as indicated by double ended arrow V. In some embodiments, theanodes 12E are not completely submerged in the bath and extend across the bath-vapor interface 22 during metal production. This vertical adjustability allows the “overlap” Y of theanodes 12E and thecathodes 14E to be adjusted. The level of theelectrolytic bath 22, the height of theanodes 12E and thecathodes 14E may require the adjustment of theanode module 12 position relative to thecathode module 14 in the vertical direction, to achieve a selected anode-cathode overlap (ACO) Y, as well as depth of submersion in theelectrolyte 22. In some embodiments, as shown inFIG. 1B , theanodes 12E are at least partially immersed in the electrolyte and thecathode electrodes 14E are completely immersed in the electrolyte. Changing the ACO Y can be used to change the cell resistance and maintain stable cell temperature. - The opposed, vertically oriented
electrodes anodes 12E due to the buoyancy of the O2 gas bubbles in the molten electrolyte. Since the bubbles are free to escape from the surfaces of theanode 12, they do not build up on the anode surfaces to form an electrically insulative/resistive layer allowing the build-up of electrical potential, resulting in high resistance and, high energy consumption. Theanodes 12E may be arranged in rows or columns with or without a side-to side clearance or gap between them to create a channel that enhances molten electrolyte movement, thereby improving mass transport and allowing dissolved alumina to reach the surfaces of theanode module 12. The number of rows ofanodes 12E can vary from 1 to any selected number and the number ofanodes 12E in a row can vary from 1 to any number. Thecathodes 14E may be similarly arranged in rows with or without side-to-side clearance (gaps) between them and may similarly vary in the number of rows and the number ofcathodes 14E in a row from 1 to any number. - The shapes of both vertical anodes and cathodes illustrated on
FIGS. 1A and 1B are generally plate shaped. Most commonly, the plates are thin and rectangular in shape. More complicated shapes, which may include sharp angles and rapidly changing cross sections can be locations of crack initiation, especially during thermal cycling periods. - New electrode shapes have then been developed and are described herein below in reference to
FIGS. 2A-D and 3. - As illustrated by the double-head arrows on the left side of
FIG. 2A , theelectrode plates -
- an ACO (Anode-Cathode Overlap) region 110 (referenced as “Y” in
FIG. 1B ), configured to be located across from anode and cathode material where the current density at the cathode plate is high or maximal for actively producing aluminum; - a
middle region 120 that is not across from anode or cathode material, where the surface current density at the electrode is low. The middle region is also known as the AMD (Anode-to-Metal-Distance) region when the electrode plate is a cathode, and as aforesaid, as the BCD (Bath to Cathode Distance) region when the electrode plate is an anode; and - a connecting
region 130 extending from themiddle region 120 for connecting theelectrode plate 100 to the cell. When theelectrode plate 100 is a cathode plate extending from the cell's bottom 14B (FIG. 1B ), this region is typically located in the metal pad 30 (seeFIG. 1B ), where the surface current density actively producing aluminum is zero, and this region is also known as the “Metal Pad region” 30.
- an ACO (Anode-Cathode Overlap) region 110 (referenced as “Y” in
- As a consequence of using inert or oxygen-evolving anodes, there is a voltage penalty of approximately 1 volt and an energy consumption penalty of approximately 3 kWh/kg compared to conventional technology. This is because inert anodes produce oxygen gas (O2) instead of the carbon dioxide gas (CO2) produced by carbon anodes. These penalties can be compensated by decreasing the current density (both anode current density and cathode plate current density).
- This decrease in current density is achieved by developing proprietary anode and cathode plate materials that are dimensionally stable. The cathode plate is preferably wettable by liquid aluminum metal. These proprietary materials are then arranged in the vertical configuration as disclosed herein that allows retaining the same current per square foot of building space at a lower current density at the active surfaces.
- Minimizing the
middle region 120 minimizes the impact on cell resistance and energy efficiency, since there is little amount of current in this region. - Various shapes for vertical electrodes are proposed. Complexity, difficulty in manufacturing, and concerns about cracking and inadequate strength have to be taken into account when considering the shape of the electrode plates, in particular the cathode plates where the metal is produced.
- Another approach consists in decreasing the
middle region 120 of theelectrode plate 100 as far as its mechanical strength and stability allow. For example, for a thin electrode plate, where the thickness is much smaller than its length or width and where the length-to-average-width aspect ratio is between 5 and 10, approximately 8 in a preferred embodiment, then the ratio of cross-sectional area at the top of the electrode plate to the cross-sectional area at the bottom of the electrode plate should be superior to 1, more preferably equal or superior to 2. - As illustrated on
FIG. 2A , theelectrode plate 100 has a straight rectangular shape in which the average cross-sectional area ratio of the ACO region to the middle or to the lower region is 1 (one). However, the surface ratio between the ACO and middle areas can be modulated or tuned by varying the ACO region in order to have a surface ratio superior to 1. -
FIG. 2B ,FIG. 2C andFIG. 2D illustrate more complex shapes with a larger area of the electrode plates in regions of high current density and a smaller area in regions of low current density. One can select the electrode plate shape and dimensions that simultaneously optimize cell voltage, energy consumption, and mechanical strength of the electrode plate. -
FIG. 2B illustrates anelectrode plate 200 having a goal post shape with a pair ofnarrow legs 210 on either side with agap 220 in the middle and connectingregions ACO region 110. -
FIG. 2C illustrates anelectrode plate 300 having a paddle shape wider in theACO region 110 and narrower in the middle/connectingregions -
FIG. 2D illustrates anelectrode plate 400 having a trapezoidal shape, wherein the width of the electrode plate is continuously sizing down from theACO region 110 to themiddle region 120 and then to the connectingregion 130. - The shape which results in the highest current density is the one that has the least area in the middle/connecting
regions ACO region 110, such as withgoal post shape 200 and thepaddle shape 300. - The
trapezoidal shape 400 ofFIG. 2D preferably combines the advantages of maximizing the metal produced in theupper ACO region 110, with ease of manufacture (i.e., the parts can be made as net-shape without cut-outs) with lower manufacturing cost, adequate strength, and avoidance of abrupt changes in cross section or inside cuts, that be sources of crack initiation (i.e., no introduction of weak points or crack initiation sites). - Typically, the electrode plates as defined herein, when used as a cathode plate, can be made of titanium diboride (TiB2) or zirconium diboride (ZrB2). Any material that is electrically conductive, resistant to molten metal and electrolyte, and wettable to a metal, such as aluminum, can be used without departing from the scope of the present disclosure.
- As illustrated on
FIG. 4 andFIG. 5 , it is also disclosed amethod 1000 or amethod 2000 respectively for controlling the current density of a plurality of electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows in an electrolytic cell, the electrode plate defining: a connecting region for connecting the electrode plate to the electrolytic cell; a middle region extending from the connecting region without overlapping adjacent electrode(s); and an ACO region extending from the middle region and configured for overlapping adjacent electrodes(s); wherein each electrode plate comprises a surface for facing another electrode plate of the adjacent row. - As illustrated on
FIG. 4 , themethod 1000 comprises the step of: -
- maximizing current density in the ACO region by varying a ratio of the ACO region's surface area to the middle region's surface area such as the ACO/middle surface area ratio is superior to one 1100.
- As illustrated on
FIG. 5 , themethod 2000 comprises the step of: -
- providing electrode plates in which an average cross-sectional area ratio of the ACO region to the middle and connecting regions is superior to one in order to maximize current density in the ACO region while retaining a mechanical strength of the connecting region for supporting the
electrode plate 2100.
- providing electrode plates in which an average cross-sectional area ratio of the ACO region to the middle and connecting regions is superior to one in order to maximize current density in the ACO region while retaining a mechanical strength of the connecting region for supporting the
- As illustrated on
FIG. 6 , it is also disclosed amethod 3000 for maximizing the current density of an electrolytic cell comprising a plurality of electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows in an electrolytic cell. Themethod 3000 comprising the step of: -
- replacing each of existing electrodes plates of the cell by the electrodes plate as disclosed herein 3100.
-
FIG. 3 shows an example of anelectrode plate 500 in accordance with a preferred embodiment of the present disclosure comprising as well anACO region 110, a connectingregion 130 and amiddle region 120 extending therebetween. - The
electrode plate 500 and thetrapezoidal electrode plate 400 ofFIG. 2D differ in that theopposite edges region 130 of theplate 500 are parallel one to the other. The width of theelectrode plate 500 is continuously sizing down from X1 at thetop end 510 of theACO region 110 to X2 at thebottom end 520 of themiddle region 120, thebottom 530 of the plate forming the connectingregion 130 having a rectangular-like shape with theparallel edges - According to a preferred embodiment, as shown on
FIG. 3 , theplate 500 may further have a round transition between thetop end 510 and each of the twoopposite edges ACO region 110, identified with the radius R1. Furthermore, theplate 500 may have a round transition between thebottom end 530 and each of the twoopposite edges region 130, identified with the radius R2. Such round transitions R1 and/or R2 allow avoiding to introduce weak points or crack initiation sites of theelectrode plates 500. - Table 1 below provides some dimensions of the
electrodes plates 500 illustrated onFIG. 3 , with L representing the total length of the electrode plate. -
TABLE 1 Example of electrode plate (FIG. 3) Length (L) 581.8 ± 7.5 mm ACO region (110) 406 ± 10 mm Connecting region (130) 78.6 ± 1.0 mm Top end (X1) 86 ± 1.5 mm Bottom end (X2) 53.8 ± 1.0 mm Round transition (radius R1) 25.3 ± 0.5 mm Round transition (radius R2) 12.6 ± 0.5 mm - The electrode plates as disclosed herein avoids the weaknesses discussed in accordance with the previous embodiments because there are no sharp geometry changes or narrow cross sections. The parts can be made into net shapes, without cut-outs, which can introduce flaws and crack initiation sites.
- The invention enables metal production with competitive energy efficiency. The invention also allows for less heat loss in the cathode plate(s).
- While illustrative and presently preferred embodiments of the disclosure have been described in detail hereinabove, it is to be understood that the inventive concepts may be otherwise variously embodied and employed and that the appended claims are intended to be construed to include such variations except insofar as limited by the prior art.
Claims (25)
1. An electrode plate for the electrolytic production of a metal using an electrolytic cell comprising a plurality of said electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows of said anode and cathode plates, the electrode plate defining:
a connecting region adjacent a first end of the electrode plate for connecting the electrode plate to the electrolytic cell;
a middle region extending from the connecting region without overlapping adjacent electrode plates; and
an anode-cathode overlapping (ACO) region extending from the middle region to a second end of the electrode plate opposite to the first end, and configured for overlapping adjacent electrode plate(s);
wherein the electrode plate comprises two opposite surfaces for facing surfaces of electrode plates of adjacent rows; and
wherein a ratio of the ACO region's surface area to the middle region's surface area is superior to one in order to maximize current density in the ACO region.
2. The electrode plate of claim 1 , wherein the ACO/middle surface ratio is equal or superior to 2.
3. The electrode plate of claim 1 , wherein the electrode plate has a rectangular shape, wherein a width of the electrode plate is constant from the ACO region to the middle and connecting regions.
4. The electrode plate of claim 1 , wherein the electrode plate has a goal post shape wherein the middle and connecting regions define a pair of legs on either side thereof, with a central gap between the legs below the ACO region.
5. The electrode plate of claim 1 , wherein the electrode plate has a paddle shape, wherein the ACO region has a first width, the middle and connecting regions have a second width, the second width being inferior to the first width.
6. The electrode plate of claim 1 , wherein the electrode plate has a trapezoid shape wherein a width of the electrode plate constantly decreases from the second end to the first end of the electrode plate.
7. The electrode plate of claim 1 , wherein the ACO region and the middle region of the electrode plate has a trapezoid shape with a width of the electrode plate constantly decreases from the second end of the electrode plate to a junction between the middle and connecting regions, the connecting region having a rectangular shape.
8. The electrode plate of claim 1 , wherein a surrounding edge of the surfaces has round transitions between the first end of the plate and the connecting region, and/or the surrounding edge has round transitions between the second end the ACO region.
9. The electrode plate of claim 1 , wherein the metal to produce is aluminum, the electrode plate being wettable by liquid aluminum metal.
10. The electrode plate of claim 1 , wherein the electrode plate is a cathode plate.
11. An electrode plate for the electrolytic production of a metal using an electrolysis cell comprising a plurality of said electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows of said anode and cathode plates, the electrode plate defining:
a connecting region adjacent a first end of the electrode plate for connecting the electrode plate to the electrolytic cell;
a middle region extending from the connecting region without overlapping adjacent electrode(s); and
an ACO region extending from the middle region and configured for overlapping adjacent electrodes(s);
wherein an average cross-sectional area ratio of the ACO region to the middle and connecting regions is superior to one in order to maximize current density in the ACO region while retaining a mechanical strength of the connecting region for supporting the electrode plate.
12. The electrode plate of claim 11 , wherein the average ACO/middle cross-sectional area ratio is equal or superior to 2.
13. The electrode plate of claim 11 , wherein the electrode plate has a goal post shape wherein the middle and connecting regions define a pair of legs on either side thereof, with a central gap between the legs below the ACO region.
14. The electrode plate of claim 11 , wherein the electrode plate has a paddle shape, wherein the ACO region has a first width, the middle and connecting regions have a second width, the second width being inferior to the first width.
15. The electrode plate of claim 11 , wherein the electrode plate has a trapezoid shape wherein a width of the electrode plate constantly decreases from the second end to the first end of the electrode plate.
16. The electrode plate of claim 11 , wherein the ACO region and the middle region of the electrode plate has a trapezoid shape with a width of the electrode plate constantly decreasing from the second end of the electrode plate to a junction between the middle and connecting regions, the connecting region having a rectangular shape.
17. The electrode plate of claim 11 , wherein the electrode plate comprises two opposite surfaces for facing surfaces of electrode plates of adjacent rows, and wherein a surrounding edge of the surfaces has round transitions between the first end of the plate and the connecting region, and/or the surrounding edge has round transitions between the second end the ACO region.
18. The electrode plate of claim 11 , wherein the metal is aluminum, the electrode plate being wettable by liquid aluminum metal.
19. The electrode plate of claim 11 , wherein the electrode plate is a cathode plate.
20. (canceled)
21. (canceled)
22. (canceled)
23. (canceled)
24. A method for controlling the current density of a plurality of electrodes plates defining anode and cathode plates vertically aligned and arranged in alternating rows in an electrolytic cell, the electrode plate defining:
a connecting region for connecting the electrode plate to the electrolytic cell;
an middle region extending from the connecting region without overlapping adjacent electrode(s); and
an ACO region extending from the middle region and configured for overlapping adjacent electrodes(s);
the method comprising the step of:
providing electrode plates in which an average cross-sectional area ratio of the ACO region to the middle and connecting regions is superior to one in order to maximize current density in the ACO region while retaining a mechanical strength of the connecting region for supporting the electrode plate.
25. (canceled)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US18/038,804 US20240003031A1 (en) | 2020-11-27 | 2021-11-25 | Controlling electrode current density of an electrolytic cell |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US202063118774P | 2020-11-27 | 2020-11-27 | |
US18/038,804 US20240003031A1 (en) | 2020-11-27 | 2021-11-25 | Controlling electrode current density of an electrolytic cell |
PCT/CA2021/051689 WO2022109742A1 (en) | 2020-11-27 | 2021-11-25 | Controlling electrode current density of an electrolytic cell |
Publications (1)
Publication Number | Publication Date |
---|---|
US20240003031A1 true US20240003031A1 (en) | 2024-01-04 |
Family
ID=81753695
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US18/038,804 Pending US20240003031A1 (en) | 2020-11-27 | 2021-11-25 | Controlling electrode current density of an electrolytic cell |
Country Status (8)
Country | Link |
---|---|
US (1) | US20240003031A1 (en) |
EP (1) | EP4251790A1 (en) |
CN (1) | CN117203373A (en) |
AU (1) | AU2021388087A1 (en) |
CA (1) | CA3197052A1 (en) |
DK (1) | DK202370308A1 (en) |
WO (1) | WO2022109742A1 (en) |
ZA (1) | ZA202305469B (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AU2022343028A1 (en) * | 2021-09-07 | 2024-02-29 | Elysis Limited Partnership | An electrode body of an electrode for the electrolytic production of a metal |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4865701A (en) * | 1988-08-31 | 1989-09-12 | Beck Theodore R | Electrolytic reduction of alumina |
EA036662B1 (en) * | 2016-03-25 | 2020-12-04 | АЛКОА ЮЭсЭй КОРП. | Electrode configurations for electrolytic cells and related methods |
CA3019368C (en) * | 2016-03-30 | 2020-10-27 | Alcoa Usa Corp. | Apparatuses and systems for vertical electrolysis cells |
-
2021
- 2021-11-25 AU AU2021388087A patent/AU2021388087A1/en active Pending
- 2021-11-25 CA CA3197052A patent/CA3197052A1/en active Pending
- 2021-11-25 US US18/038,804 patent/US20240003031A1/en active Pending
- 2021-11-25 WO PCT/CA2021/051689 patent/WO2022109742A1/en active Application Filing
- 2021-11-25 EP EP21896012.8A patent/EP4251790A1/en active Pending
- 2021-11-25 CN CN202180079616.0A patent/CN117203373A/en active Pending
-
2023
- 2023-05-19 ZA ZA2023/05469A patent/ZA202305469B/en unknown
- 2023-06-19 DK DKPA202370308A patent/DK202370308A1/en unknown
Also Published As
Publication number | Publication date |
---|---|
AU2021388087A1 (en) | 2023-06-22 |
CA3197052A1 (en) | 2022-06-02 |
DK202370308A1 (en) | 2023-07-07 |
ZA202305469B (en) | 2024-01-31 |
EP4251790A1 (en) | 2023-10-04 |
WO2022109742A1 (en) | 2022-06-02 |
CN117203373A (en) | 2023-12-08 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US11585003B2 (en) | Electrode configurations for electrolytic cells and related methods | |
CA1219551A (en) | Apparatus and method for electrolysis and float | |
EP0560814B1 (en) | Electrode assemblies and multimonopolar cells for aluminium electrowinning | |
CA1217454A (en) | Apparatus and method for electrolysis and inclined electrodes | |
US6558525B1 (en) | Anode for use in aluminum producing electrolytic cell | |
DK202370308A1 (en) | Controlling electrode current density of an electrolytic cell | |
US11180862B2 (en) | Advanced aluminum electrolysis cell | |
US20040178079A1 (en) | Arrangement of anode for utilisation in an electrolysis cell | |
KR880000709B1 (en) | Electrolytic cell for mg chloride | |
RU2758697C1 (en) | Method for electrolytic production of aluminium using solid electrodes | |
JPH0111722Y2 (en) | ||
AU2002251602A1 (en) | Arrangement of anode for utilisation in an electrolysis cell |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: ELYSIS LIMITED PARTNERSHIP, CANADA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:ALCOA USA CORP.;REEL/FRAME:063762/0396 Effective date: 20220303 Owner name: ALCOA USA CORP., PENNSYLVANIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:D'ASTOLFO, LEROY;MICKELSON, LARRY;RUAN, YIMIN;REEL/FRAME:063762/0213 Effective date: 20220207 |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION |