Apparatus and method for operating an electrolytic cell

Abstract

An apparatus for transporting anode assemblies outside an electrolytic cell, also known as a transfer box or TB, is described. An apparatus for transporting anode assemblies or cell preheaters outside an electrolytic cell, also known as a cell preheater lifting beam or CPLB, is also disclosed. The TB and CPLB are used together to start up an electrolytic cell or replace spent anode assemblies while maintaining production of non-ferrous metals (e.g., aluminum or aluminum). The thermal insulation of the TB allows anode temperature uniformity to be maintained and prevents thermal shock when inert anodes are introduced into a hot electrolytic bath. The TN and CPLB allow the anode assembly or cell preheater to be accurately positioned above the electrolytic cell before mechanical and electrical connection of the anode assembly or cell preheater to the electrolytic cell is made. Several related methods for operating an electrolytic cell are also disclosed.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims priority to U.S. Provisional Patent Application No. 62 / 822,722, filed with the U.S. Patent and Trademark Office on August 28, 2019, entitled "Apparatus and Method for Maintaining an Anode Assembly of an Electrolytic Cell," the contents of which are incorporated herein by reference. Technical Field

[0003] The present invention generally relates to systems, apparatus and methods for operating electrolytic cells, such as maintenance and replacement of anodes or cell preheaters of electrolytic cells, and more particularly, but not exclusively, for replacing stable / inert anodes of electrolytic cells, such as for the production of metals, such as but not limited to aluminum. Background Art

[0004] Aluminium metal, also known as aluminium, is produced by electrolysis of aluminium oxide, also known as alumina (IUPAC), in a molten electrolyte at about 750°C to 1000°C contained in multiple smelting pools. In the conventional Hall-Heroult process, the anode is made of carbon and is consumed during the electrolysis reaction. The anode needs to be replaced after 3 to 4 weeks.

[0005] During the experiments, it was determined that the current systems and processes for maintaining and replacing electrolytic cell anodes are not suitable when inert anodes are used instead of the traditional carbon anodes required in the Hall-Heroult process.

[0006] Furthermore, electrolytic cells operating with inert anodes require preheating, usually using a cell preheater. The cell preheater must be inserted into the cell before heating the cell and then removed from the cell before the preheated anodes are introduced into the cell.

[0007] The present invention at least partially solves the identified disadvantages when using inert anodes. Summary of the invention

[0008] According to a first aspect, the present invention relates to an insulating device for maintaining and transporting an anode assembly outside an electrolyte cell. The anode assembly includes a plurality of vertical inert anodes. The device includes: a support structure defining an internal space, the support structure being used to insulate the anode assembly when in the internal space; an actuator assembly coupled to the support structure and configured to support the anode assembly, the actuator assembly being operable to move the anode assembly between an insulating position and a loading-unloading position: in the insulating position, the anode assembly is located in the internal space of the support structure; and in the loading-unloading position, the anode assembly is located outside the support structure, for loading the anode assembly into the actuator assembly and unloading the anode assembly from the actuator assembly; and a heat shield assembly extending from the inner surface of the support structure, for insulating the anode assembly when the anode assembly is in the internal space.

[0009] According to another aspect, the present invention relates to a device for transporting an anode assembly outside an electrolyte cell. The anode assembly includes a plurality of anodes, preferably vertical inert anodes. The device includes: a support structure defining an internal space; an actuator assembly coupled to the support structure and configured to support the anode assembly, the actuator assembly being operable to move the anode assembly between an insulating position and a loading-unloading position: in the insulating position, the anode assembly is located in the internal space of the support structure; and in the loading-unloading position, the anode assembly is located outside the support structure for loading the anode assembly into the actuator assembly or unloading the anode assembly from the actuator assembly; and a thermal system assembly supported by the support structure for maintaining the temperature of the anode assembly when the anode assembly is located in the internal space.

[0010] According to a preferred embodiment, the actuator assembly further comprises an electrical insulation system for electrically isolating the anode assembly from the actuator assembly.

[0011] According to a preferred embodiment, the support structure defines an open bottom connected to the internal space, and the device also includes: a door assembly, which is movably coupled to the support structure and can be operated between an open position and a closed position, wherein the open position allows the anode assembly to move between an insulating position and a loading-unloading position, and in the closed position, the door assembly closes the open bottom of the support structure.

[0012] According to a preferred embodiment, the actuator assembly includes a steering horizontal beam configured to be detachably connected to the anode assembly and to vertically move the anode assembly within the interior space.

[0013] According to a preferred embodiment, the actuator assembly comprises a first motor and a second motor supported by a support structure, each motor being coupled to a moving element arranged at opposite longitudinal ends of the steering beam, along which the steering beam is vertically raised and lowered. Preferably, the moving element comprises a threaded rod or chain driven by a motor for raising or lowering the steering beam.

[0014] According to a preferred embodiment, the actuator assembly comprises a fail-safe suspension device for removably engaging and supporting the anode assembly.Preferably, when the actuator assembly is lowered onto the anode assembly, the fail-safe suspension device engages into a corresponding manipulation pin of the anode assembly.

[0015] According to a preferred embodiment, the thermal system includes a plurality of thermal shields extending from an inner surface of the support structure for engaging corresponding surfaces of the plurality of inert anodes when the anode assembly is within the interior space.

[0016] According to a preferred embodiment, the thermal shield may comprise a refractory lining.

[0017] According to a preferred embodiment, the apparatus further comprises an electric heater module for heating the inert anode when the anode assembly is located in the interior space.

[0018] According to a preferred embodiment, the support structure is configured to allow ventilation of an upper zone of the anode assembly to maintain the upper zone at a lower temperature than a lower hot zone containing a plurality of inert anodes.

[0019] According to a preferred embodiment, the apparatus further comprises guide pins which align with the structure of the electrolyte cell to facilitate operative installation of the anode assembly therein.

[0020] According to a preferred embodiment, the device may further comprise a first electrical isolation element between the guide pin and the support structure.

[0021] According to a preferred embodiment, the actuator assembly further comprises an automatic connection assembly which electrically connects the anode assembly to the electrolytic cell. Preferably, the automatic connection assembly comprises a pneumatic wrench and a synchronized bolt system.

[0022] According to a preferred embodiment, the device may further comprise a second electrical isolation element between the automatic connection assembly and the support structure.

[0023] According to a preferred embodiment, the apparatus may further comprise a third electrically isolating element located on top of the actuator assembly.According to a preferred embodiment, the support structure comprises an attachment element located on top, the attachment element being configured to be mechanically attached to an overhead crane used to transport or deliver the apparatus.

[0024] According to a preferred embodiment, the device may further comprise a fourth electrical isolation element for isolating the device from the bridge crane.

[0025] According to yet another aspect, the present invention relates to a method for delivering an anode assembly of inert anodes at a given temperature to an electrolytic cell for producing non-ferrous metals, comprising:

[0026] preheating an inert anode of an anode assembly at a given temperature, the anode assembly being located outside the electrolytic cell;

[0027] delivering the anode assembly to the electrolytic cell while maintaining a given temperature of the preheated inert anode; and

[0028] The preheated inert anode of the anode assembly is inserted into the molten electrolyte bath of the electrolytic cell.

[0029] According to a preferred embodiment, a) the inert anodes of the anode assembly are preheated in a pretreatment station located at a distance from the electrolytic cell. The method preferably also comprises, before b), removing the anode assembly from the pretreatment station while enclosing the anode assembly in an insulated transport device configured to transport the anode assembly to the electrolytic cell while maintaining a given temperature of the inert anodes within a predetermined tolerance range.

[0030] According to a preferred embodiment, removing the anode assembly from the pre-processing station and enclosing the anode assembly in an insulated transport device comprises:

[0031] positioning an insulating transport device over an anode assembly located in an anode preconditioner;

[0032] lowering the actuator assembly from the interior space of the insulating transport device to the anode assembly;

[0033] connecting the anode assembly to the actuator assembly; and

[0034] The actuator assembly with the anode assembly connected thereto is raised from the anode assembly pre-conditioner into the interior space of the insulated transport apparatus.

[0035] According to a preferred embodiment, c) inserting the preheated inert anode of the anode assembly into the molten electrolyte bath of the electrolytic cell comprises:

[0036] Positioning the insulated transport device over the electrolytic cell;

[0037] lowering the actuator assembly and anode assembly from the insulated transport device into the electrolytic cell until the preheated inert anode is inserted into the molten electrolyte bath;

[0038] mechanically connecting the anode assembly to the electrolytic cell;

[0039] electrically connecting the inert anode of the anode assembly to the electrolytic cell; and

[0040] The anode assembly is released from the actuator assembly.

[0041] According to a preferred embodiment, lowering the anode assembly into the bath comprises aligning guide pins of the insulating transport device with corresponding receiving holes of the electrolytic cell before lowering the anode assembly into the electrolytic cell.

[0042] According to a preferred embodiment, connecting the inert anode of the anode assembly to the electrolytic cell comprises mechanically bolting the flexible portion of the anode assembly to an anode equipotential rod of the electrolytic cell.

[0043] According to a preferred embodiment, an actuator assembly is coupled to a support structure of an insulating transport apparatus, the actuator assembly comprising a handling beam configured to support the anode assembly and vertically move the anode assembly, wherein releasing the anode assembly from the insulating transport apparatus comprises releasing the anode assembly from the handling beam, and the method then further comprises:

[0044] After releasing the anode assembly from the handling beam, raising the handling beam into the support structure of the insulated transport apparatus; and

[0045] Remove the insulating transport device from the electrolytic cell.

[0046] According to a preferred embodiment, the insulating transport apparatus comprises a door assembly for a thermally insulating opening through which the anode assembly enters and leaves the insulating transport apparatus, the method further comprising:

[0047] When removing anode assemblies from the anode pre-treatment station and enclosing them in insulated transport equipment:

[0048] actuating the door assembly to an open position;

[0049] raising the anode assembly into the interior space of the insulated transport apparatus; and

[0050] closing door assembly; and

[0051] When installing the anode assembly in the electrolytic cell:

[0052] actuating the door assembly to an open position; and

[0053] The anode assembly is lowered from the interior space of the insulated transport device into the electrolytic cell.

[0054] According to another aspect, the invention relates to an apparatus for transporting spent anode assemblies or a cell preheater outside an electrolytic cell, the cell preheater being configured to be inserted into the cell to preheat the cell, after which the preheated anode assemblies are inserted into the preheated cell, the apparatus comprising:

[0055] a support structure defining an interior space;

[0056] an actuator assembly coupled to the support structure and configured to support the spent anode assembly or the cell preheater, the actuator assembly being operable to move the cell preheater between an insulating position and a load-unload position:

[0057] In the insulated position, the spent anode assembly or cell preheater is positioned within the interior space of the support structure; and

[0058] In the load-unload position, the spent anode assembly or cell preheater is located outside the support structure for loading or unloading the spent anode assembly or cell preheater to or from the actuator assembly; and

[0059] An automatic connection system configured to electrically connect a cell preheater to an electrolytic cell when installing the cell preheater into the cell, or to electrically disconnect a spent anode assembly or a cell preheater from an electrolytic cell and thereafter remove them from the cell preheater.

[0060] According to a preferred embodiment, the actuator assembly may further comprise an electrical insulation system for electrically isolating the cell pre-heater or anode assembly from the actuator assembly.

[0061] According to a preferred embodiment, the actuator assembly comprises a steering horizontal beam configured to be detachably connected to the anode assembly and to vertically move the pool preheater or anode assembly within the interior space. Preferably, the actuator assembly comprises a first motor and a second motor supported by a support structure, each motor being coupled to a moving element arranged at opposite longitudinal ends of the steering beam, respectively, along which the steering beam is vertically raised and lowered. Preferably, the moving element comprises a threaded rod or chain driven by a motor for raising or lowering the steering beam.

[0062] According to a preferred embodiment, the actuator assembly includes a fail-safe suspension device for removably engaging and supporting the pool preheater or anode assembly. Preferably, the fail-safe suspension device engages into a corresponding manipulation pin of the pool preheater or anode assembly when the actuator assembly is lowered onto the pool preheater or anode assembly.

[0063] According to a preferred embodiment, the apparatus may further comprise a heat shield supported by the support structure for protecting the support structure from heat radiation from the cell preheater or anode assembly when the cell preheater or anode assembly is removed from the cell. Preferably, the heat shield comprises a refractory lining.

[0064] According to a preferred embodiment, the support structure is configured to allow ventilation of an upper zone of the support structure to maintain the upper zone at a lower temperature than a lower hot zone containing the cell pre-heater or anodes of the anode assembly.

[0065] According to a preferred embodiment, the apparatus may further comprise guide pins which align with the structure of the electrolytic cell to facilitate installation of the cell preheater or anode assembly therein.

[0066] According to a preferred embodiment, the automatic connection assembly includes a pair of pneumatic wrenches and a synchronized bolt system.

[0067] According to a preferred embodiment, the support structure comprises an attachment element configured to be mechanically attached to an overhead crane for transporting the equipment.

[0068] According to another aspect, the present invention relates to a method for starting up an electrolytic cell for producing non-ferrous metals, the electrolytic cell being configured to contain N anode assemblies, wherein N ≥ 1. The method comprises:

[0069] a) installing N cell preheaters in the cell in place of N anode assemblies;

[0070] b) preheating the pool using N pool preheaters until a given temperature is reached in the pool;

[0071] c) pouring a molten electrolyte bath and a certain amount of molten metal into the tank;

[0072] d) removing the first cell pre-heater using an apparatus for transporting a spent anode assembly or a cell pre-heater to outside the electrolytic cell as defined herein;

[0073] e) inserting the preheated anode assembly in place of the removed cell preheater using an apparatus for transporting anode assemblies outside an electrolytic cell as defined herein, or according to a method for transporting anode assemblies of inert anodes at a given temperature to an electrolytic cell for use in the production of non-ferrous metals as defined herein, and

[0074] f) Repeat steps d) and e) (N-1) times until all cell preheaters have been replaced by preheated anode assemblies.

[0075] According to another aspect, the invention also relates to a method for replacing spent anode assemblies of an electrolytic cell during the production of non-ferrous metals, the cell comprising N anode assemblies inserted in a molten electrolytic bath at a given temperature, wherein N ≥ 1. The method comprises:

[0076] a) removing spent anode assemblies from a cell using an apparatus for transporting anode assemblies or a cell preheater outside an electrolytic cell as defined herein;

[0077] b) immediately after step a), inserting a new anode assembly preheated at a given temperature using a device for transporting anode assemblies outside an electrolytic cell as defined herein, or according to a method for transporting anode assemblies of inert anodes at a given temperature to an electrolytic cell as defined herein;

[0078] wherein steps a) and b) are carried out while the cell is producing non-ferrous metals, and

[0079] Therein, steps a) and b) are repeated for each spent anode assembly of the cell to be replaced.

[0080] According to a preferred embodiment, the non-ferrous metal is aluminum and the N anode assemblies comprise a plurality of inert anodes.

[0081] According to a preferred embodiment, the inert anode is a vertical inert anode.

[0082] The present invention is compatible with inert anode cell and anode assembly configurations and solves the thermal shock problem. Advantageously, when inert anodes are introduced into a hot electrolysis bath, the insulation of the transfer box allows anode temperature uniformity to be maintained and thermal shock to be prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] Further features and exemplary advantages of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0084] Figure 1 is a schematic diagram of an anode assembly according to a preferred embodiment;

[0085] Figure 2 shows the transfer (B) of the anode assembly from a pretreatment station (A) to an electrolytic cell (C) according to a preferred embodiment;

[0086] Figure 3 is a schematic open view of a transfer box according to a preferred embodiment, wherein (A) the handling beam is in its insulating position, and (B) the handling beam is in its loading-unloading position;

[0087] Figure 4 is a schematic diagram of a transfer box in its insulated position according to a preferred embodiment, showing (A) the anode assembly behind the thermal shield assembly, and (B) the anode assembly secured to a steering beam within the transfer box;

[0088] Figure 5 is a schematic diagram of a transfer box according to a preferred embodiment, showing: (A) the transfer box in its loading-unloading position with the anode assembly positioned below the thermal shield assembly, and (B) a side view thereof with the door assembly in an open position;

[0089] Figure 6 is a schematic diagram of a transfer box according to a preferred embodiment, wherein the handling beam is in its insulated position and showing the various mechanisms for moving the handling beam up and down, clamping / releasing the anode assembly and tightening the electrical connections;

[0090] Figure 6B shows different positions of the electrical isolation elements of the transfer box according to the preferred embodiment;

[0091] Figure 7 shows details of the automatic connection of a transfer box or device to an electrolytic cell according to a preferred embodiment;

[0092] Figure 8 shows the different steps of loading the preheated anode assembly from the pretreatment station to the transfer box in views (A) to (C) and unloading the anode assembly from the transfer box to the electrolytic cell in view (D) according to a preferred embodiment;

[0093] Fig. 9 Different views of a transfer box and a pre-treatment station according to a preferred embodiment are shown: a front view (A) and a side view (B) when anode assemblies are loaded into the transfer box, and a front view (C) when a crane lifts the transfer box;

[0094] Fig.10 Shown is the unloading of the anode assembly from the transfer box into the electrolytic cell according to the preferred embodiment: side view (A) and front view (B);

[0095] Fig.11 Shown is the removal of the transfer box once the anode assembly is loaded into the electrolytic cell according to a preferred embodiment: side view (A) and front view (B);

[0096] Fig.12 is a flow chart showing a method for delivering an anode assembly of inert anodes at a given temperature to an electrolytic cell for producing non-ferrous metals according to a preferred embodiment;

[0097] Fig.13 is a flow chart showing a method according to a first preferred embodiment;

[0098] Fig.14 is a flow chart showing a method according to a second preferred embodiment;

[0099] Fig.15 is a flow chart showing a method according to a third preferred embodiment;

[0100] Fig.16 is a flow chart showing a method according to a fourth preferred embodiment;

[0101] Fig.17 is a schematic diagram of a pool preheater (CP) according to a preferred embodiment;

[0102] Fig.18 shows the transfer of a spent anode assembly (SAA) from an electrolytic cell (left) to a maintenance chariot (right) in accordance with a preferred embodiment;

[0103] Fig.19 shows the transfer of a cell preheater (CP) from an electrolytic cell (left) to a transport vehicle (right) according to a preferred embodiment;

[0104] Fig. 20 is a schematic open view of an apparatus for transporting anode assemblies or cell preheaters outside an electrolytic cell (also referred to herein as CPLB) according to a preferred embodiment, with (left) a handling beam in its insulated position and (right) a handling beam in its loading-unloading position;

[0105] Fig.21is a schematic diagram of a CPLB in its insulating position according to a preferred embodiment, wherein the CP is fixed to a steering beam inside the CPLB;

[0106] Fig. 22 is a schematic diagram of a CPLB in its insulating position according to a preferred embodiment, wherein the SAA is fixed to a steering beam inside the CPLB;

[0107] Fig.23 is a schematic diagram of a CPLB according to a preferred embodiment, showing: (left) the CPLB in its loading-unloading position with the SAA attached to the steering beam, and (right) a side view thereof;

[0108] Fig.24 is a schematic diagram of a CPLB according to a preferred embodiment, showing: (left) the CPLB in its loading-unloading position, with the CP attached to a steering beam, and (right) a side view thereof;

[0109] Fig.25 is a schematic open view of a CPLB according to a preferred embodiment, with the steering beam in its insulating position, supporting the SAA;

[0110] Fig.26 is a schematic open view of a CPLB according to a preferred embodiment, with the steering beam in its insulating position, supporting the CP;

[0111] Fig. 27 is a schematic open view of a CPLB supporting a CP on an electrolytic cell according to a preferred embodiment, wherein (A) and (B) show details of a pair of automatic connections of the CPLB to the electrolytic cell;

[0112] Fig.28 is a schematic open view of a CPLB supporting a SAA on an electrolytic cell according to a preferred embodiment, wherein (A) details of an automatic connection of the CPLB to the electrolytic cell;

[0113] Fig.29 The first step of bringing the CPLB close to the top of the transport vehicle containing the CP according to the preferred embodiment is shown, (left) front view, (right) side view;

[0114] Fig.30 Shows the second step of connecting the CPLB to the CP in the transport vehicle according to the preferred embodiment, (left) front view, (right) side view;

[0115] Fig.31 The third step of lifting the CPLB and CP from the transport vehicle according to the preferred embodiment is shown, (left) front view, (right) side view;

[0116] Fig.32The fourth step of lowering the CP from the CPLB located above the electrolytic cell according to the preferred embodiment is shown, (left) front view, (right) side view;

[0117] Fig.33 shows the first step of removing the CP from the electrolytic cell once the electrolytic cell is heated by the CP, according to a preferred embodiment, wherein the CPLB is located above the electrolytic cell containing the CP, (left) front view, (right) side view;

[0118] Fig.34 shows the second step of removing the CP from the heated electrolytic cell according to the preferred embodiment, wherein the handling beam of the CPLB is lowered before connecting with the CP, (left) front view, (right) side view;

[0119] Fig.35 The third step of raising CPLB and CP from the electrolytic cell according to the preferred embodiment is shown, (left) front view, (right) side view;

[0120] Fig.36 The fourth step of lowering and unloading the CP from the CPLB located above the transport vehicle according to the preferred embodiment is shown, (left) front view, (right) side view;

[0121] Fig.37 The first step of removing SAA from an electrolytic cell according to a preferred embodiment is shown, wherein a CPLB is located above the electrolytic cell containing SAA, (left) front view, (right) side view;

[0122] Fig.38 The second step of removing the SAA from the electrolytic cell according to the preferred embodiment is shown, wherein the manipulator beam of the CPLB is lowered before connecting with the SAA, (left) front view, (right) side view;

[0123] Fig.39 The third step of raising the CPLB and SAA from the electrolytic cell according to the preferred embodiment is shown, (left) front view, (right) side view;

[0124] Fig.40 4. The fourth step of positioning the CPLB containing the SAA above the transport vehicle before lowering and unloading the SAA into the transport vehicle according to the preferred embodiment is shown, (left) front view, (right) side view;

[0125] Fig.41 shows different locations of electrical isolation elements of a CPLB according to a preferred embodiment;

[0126] Fig.42 is a flow chart showing a method for starting up an electrolytic cell for producing non-ferrous metals according to a preferred embodiment; and

[0127] Fig.43 is a flow chart illustrating a method for replacing spent anode assemblies of an electrolytic cell during non-ferrous metal production, according to a preferred embodiment. DETAILED DESCRIPTION

[0128] Transfer Box (TB):

[0129] Carbon anodes can withstand the thermal shock that occurs when a cold anode is introduced into a hot molten electrolyte, so no special precautions need to be taken to preheat or avoid temperature differences between the new anode and the electrolytic bath.

[0130] Inert anodes are typically made of stabilized composite materials that are sensitive to thermal shock. As new or improved smelting processes are developed using stabilized composite anodes, new systems, equipment and methods are required to maintain and replace anode components in smelting cells.

[0131] In the inert anode process, the anode is made of a composite material. Figure 1 and 2 As shown, the anode assembly 10 includes a horizontal beam 12, including a flexible anode assembly 11, and an assembly of individual anodes 14 is suspended from the flexible anode assembly 11. The anode assembly 10 is typically mounted by a bridge crane 30 (e.g. Figure 8-11 ) to be typically positioned transversely to the electrolytic cell 40 (as shown Figure 10-11 shown).

[0132] like Figure 2 As shown, the anode assembly (AA) 10 is first placed in the anode pretreatment station 20, wherein the AA is preferably uniformly preheated to a predetermined temperature close to the temperature of the molten electrolyte bath 42 of the electrolytic cell 40. The subsequent transportation of the anode assembly 10 from the anode pretreatment station 20 to the cell 40 is preferably carried out in a manner that maintains the temperature and temperature uniformity of the inert anodes 14. Preferably, when the inert anodes are immersed in the electrolyte bath, the temperature of the inert anodes in the anode assembly (AA) is plus or minus 25°C (predetermined tolerance range) compared to the bath temperature. The temperature loss in the transfer box is less than 10°C per hour. For this purpose, a new device 100 has been developed for transporting anode assemblies of inert anodes while maintaining the temperature of the preheated inert anodes before inserting the inert anodes of the anode assembly into the molten electrolyte bath of the electrolytic cell.

[0133] like Figures 3 to 7 As disclosed and illustrated, the apparatus 100, also referred to herein as a "transfer box" or TB, first includes a support structure 110, typically made of assembled sheet metal elements. The apparatus 100 defines an interior space 112 configured to house the anode assembly 10.

[0134] like Figure 3-8As shown, the transfer box 100 includes an actuator assembly 120, which is coupled to the support structure 110 and includes a manipulation beam 122 configured to support the anode assembly 10. The actuator assembly 120 is operable to move the manipulation beam 122 relative to the support structure between an insulating position and a loading-unloading position, wherein the insulating position ( Figure 3 (A)- Figure 4 (A)) is used to hold the anode assembly 10 in the internal space 112 of the support structure, and the loading-unloading position is outside the internal space 112 for loading and unloading the anode assembly onto the handling beam 122 ( Figure 3 (B)- Figure 4 (B)).

[0135] like Figure 5 As better shown in (B), the support structure 110 includes an open bottom 114 communicating with the interior space 112, and a door assembly 116 ( Figure 5 The door assembly 116 is operably coupled to the support structure 110 to move between an open position and a closed position, thereby allowing the anode assembly 10 to move in and out of the transfer box 100. When the anode assembly 10 is in the transfer box 100, the door assembly 116 closes the open bottom 114 of the support structure 110.

[0136] The support structure 110 is configured to move from the insulating position to the loading-unloading position to the open state (see Figure 5 ), and moves to the closed state when the operating beam 122 moves from the loading-unloading position to the insulating position (see Figure 6 ).

[0137] In a conventional Hall-Heroult cell, the anode assembly typically consists of a vertical stem which is inserted into the carbon anode and is manipulated by a bridge crane which positions the new anode against the cell anode frame (centered on the longitudinal axis of the cell) and connects the anode to the frame (mechanical and electrical connections) via connectors actuated by the crane. Lateral positioning of the anode assembly is achieved by inserting the stem between two rails bolted to the anode frame. Vertical positioning is achieved by moving the anode mast of the bridge crane from which the anode assembly is suspended. Vertical positioning of the new anode assembly is critical to the performance of the cell, since the anode and cathode active faces are horizontal.

[0138] In the case of an inert anode cell, it must be understood that high positioning accuracy is required in the longitudinal vertical direction (z axis) and in the transverse direction (x and y axes) to ensure the correct anode / cathode distance, since the anode and cathode active faces are vertical. Vertical positioning is usually achieved by the movement of a lifting mechanism of a bridge crane 30, from which the transfer box 100 is suspended. Electrical connection is usually achieved by bolting the anode assembly flexible member 11 to the anode equipotential rod longitudinal to the cell. Figures 3 to 6 As shown, the actuator assembly 120 allows the manipulation beam 122 to be moved between the isolation position and the load-unload position (z-axis) while preventing horizontal tilting of the anode assembly. The actuator assembly 120 may include a first motor 124 and a second motor 126, each of which is respectively coupled to a corresponding threaded rod 125-127, which is arranged at opposite longitudinal ends of the manipulation beam 122, and the beam is moved along the threaded rod 125-127 ( Figure 3 (A)- Figure 4 The two lifting motors 124-126 are preferably coupled so as to allow the anode assembly to be lowered in a completely horizontal manner and to ensure that the horizontal beam 12 of the anode assembly 10 can freely engage its locating pins.

[0139] like Figure 6 As shown, the handling beam 122 may include at least one fail-safe suspension device 130 for fixing to and supporting the anode assembly. When the handling beam is lowered onto the anode assembly, the fail-safe suspension device 130 engages into a corresponding operating pin 132 of the anode assembly. The fail-safe device is preferably a semi-automatic fail-safe device that engages into the anode assembly operating pin when lowered onto the anode assembly, thereby reducing the risk of the anode assembly falling through. The fail-safe device 130 can only be disengaged when the anode assembly rests on the upper structure 44 of the electrolytic cell 40.

[0140] like Figures 4 to 6 As shown, the apparatus 100 may further include a heat shield assembly 140 extending from an inner surface of the support structure 110, for facing the inert anode of the anode assembly, and operably insulating the anode assembly 10 on multiple sides when the anode assembly is in the internal space 112. The heat shield assembly 140 may include a plurality of thermal panels 142, which are vertically and horizontally arranged within the support structure, for engaging with corresponding vertical surfaces of the inert anode 14 when the anode assembly 10 is in the internal space 112. For example, the heat shield assembly may include a refractory lining 144. In addition, the heat shield assembly may be equipped with a heater system, such as an electric heater, for heating or maintaining the temperature of the preheated inert anode when the anode assembly is in the internal space.

[0141] Figure 6The inert anode 14 of the anode assembly 10 is shown surrounded by a thermal panel 142 of a thermal shield 140 and a bottom door 116 also equipped with a thermal lining 144. The support structure 110 then defines a low thermal zone 146 including the inert anode 14 and wherein the temperature of the inert anode 14 is maintained during transport of the device 100 to the cell (see Figure 2 or 9). The insulation structure 100 is also configured to allow ventilation of the upper cold zone 148 within the interior space 112 above the anode assembly 10 and the lower hot zone 144 to maintain the upper cold zone 148 at a lower temperature than the hot zone. For example, when the temperature inside the lower hot zone is about 900°C, the temperature of the upper cold zone may be about 150°C.

[0142] Figure 6B Different positions of the electrical isolation elements 151-154 of the transfer box 100 are shown. In particular, the first electrical isolation element 151 can be positioned between the support structure 110 and the guide pin 118, the second electrical isolation element 152 is located on the top of the actuator assembly 120, the third electrical isolation element 153 is located between the automatic connection assembly 134 and the support structure 110, and finally there is a fourth electrical isolation element 154 for isolating the transfer box 100 from the crane, for example, in cooperation with the operating hook 160 located on the top of the box. This fourth element 154 can also be part of the main support bridge or the crane 30.

[0143] like Figure 6-8 As shown, in order to ensure that the anode assembly is aligned vertically (z axis) and laterally (x, y axis) with the cell 40, the apparatus 100 may also include guide pins 118 that align to matching apertures 119 in the upper structure of the electrolytic cell 40, allowing such precise positioning on the cell. The guide pins 118 may be moved using a movement system 117 to facilitate insertion of the pins into their corresponding matching apertures 119. Figure 8 As shown in FIG. 2A , the pin 118 is also configured to be aligned with or inserted into the matching aperture 22 of the pre-processor 20 .

[0144] like Figure 7 As shown, the actuator assembly 120 may also include an automatic connection assembly 134 to electrically connect the anode assembly 10 to the electrolytic cell 40. Preferably, the electrical connection is a high-intensity (HI) connection. The automatic connection assembly 134 may include a pneumatic wrench, a synchronized bolt system, and a high-ampere connector.

[0145] like Figure 8 As shown, the apparatus 100, and more specifically the support structure 110, is configured to be mechanically attached to the bridge crane 30 for transportation.

[0146] According to another aspect, the present invention relates to a method for delivering an anode assembly of inert anodes at a given temperature to an electrolytic cell for the production of non-ferrous metals such as, but not limited to, aluminum. Figure 2 and 8 Figures to 11 and Figures 12 to 16 Flowchart of the process.

[0147] like Figure 2 and 12 As shown, method 1000 generally includes the steps of:

[0148] 1100: preheating the inert anode 14 of the anode assembly 10 at a given temperature, the anode assembly 10 being located outside the electrolytic cell 40;

[0149] 1200: transporting the anode assembly 10 toward the electrolytic cell while maintaining a given temperature of the preheated inert anode; and

[0150] 1300: Insert the preheated inert anode of the anode assembly into the molten electrolyte bath of the electrolytic cell.

[0151] like Figure 8 As shown in Fig. 13, step a) of preheating the inert anode 1100 of the anode assembly is performed in a pretreatment unit 20, which is also called a pretreatment station and is located at a certain distance from the electrolytic cell ( Figure 8 A), 1110. The preprocessor is configured to receive an anode assembly ( Figure 8 A) and heating the inert anode at a given or predetermined temperature, which should be close to the temperature of the molten electrolyte bath 42 of the electrolytic cell 40 into which the inert anode will be inserted. In order to maintain the temperature of the inert anode during transportation to the cell 40, the method then preferably further comprises, before step b), 1120, a step of removing the anode assembly from the anode assembly preprocessor 20 while the anode assembly is enclosed inside an insulating transport device 100, the insulating transport device 100 being configured to transport the anode assembly toward the electrolytic cell while maintaining a given temperature of the inert anode constant or nearly constant.

[0152] according to Figure 8 and Fig.14 In the preferred embodiment shown, the step 1120 of removing the anode assembly from the anode assembly preprocessor and sealing the anode assembly in an insulated transport device may include the steps of:

[0153] 1121: Position the insulating transport device 100 on the anode assembly 10 located in the anode preprocessor 20 (see Figure 8 (A)), for example using a crane 30 having a cable fixed to a transfer box;

[0154] 1122: Lower the manipulator beam 122 from the inner space 112 of the insulated transport device to the anode assembly (see Figure 8 (B));

[0155] 1223: Connecting the anode assembly to the steering beam; and

[0156] 1224: Raise the handling beam connected with the anode assembly from the anode assembly preprocessor 20 to the inner space of the insulating transport equipment ( Figure 8 (C)).

[0157] According to Fig. 9 and 15 In the preferred embodiment shown, the step 1200 of transporting the anode assembly 10 toward the electrolytic cell 40 while maintaining a given temperature of the preheated inert anode may include the steps of:

[0158] 1210: Use a crane to lift and transport equipment, and

[0159] 1220: While maintaining the temperature of the inert anode 14 in the transport box, the crane 30 is controllably moved toward the electrolytic cell ( Fig. 9 and 10 ), for example due to a thermal shield or other means for maintaining a constant temperature as described herein.

[0160] according to Figure 8 , 10 In the preferred embodiment shown in FIG. 16 , the step 1300 of inserting the preheated inert anode of the anode assembly into the molten electrolyte bath of the electrolytic cell comprises:

[0161] 1310: Positioning of insulated transport equipment above the electrolytic cell (see Figure 8 of (C) or 10 of (A));

[0162] 1320: Lower the anode assembly 10 from the insulated transport device into the electrolytic cell until the preheated inert anode 14 is inserted into the molten electrolyte bath ( Figure 8 of (D) or 10 of (B);

[0163] 1330: Mechanically connecting the anode assembly 10 to the electrolytic cell;

[0164] 1340: electrically connecting the inert anode 14 of the anode assembly 10 to the electrolytic cell; and

[0165] 1350: Release anode assembly from insulated transport equipment.

[0166] According to a preferred embodiment, the step of lowering the anode assembly into the production pot or bath of the cell may comprise the step of aligning guide pins of the insulating transport device with corresponding receiving holes of the electrolytic cell and simultaneously lowering the anode assembly into the electrolytic cell aligned with the guide pins.

[0167] According to a preferred embodiment, the step of electrically connecting the inert anode of the anode assembly to the electrolytic cell may comprise pneumatically bolting the flexible portion of the anode assembly to an anode equipotential rod of the electrolytic cell.

[0168] As described herein, the insulated transport device includes a support structure and an actuator assembly coupled thereto, the actuator assembly including a manipulator beam configured to support and vertically move the anode assembly. Thus, the step of releasing the anode assembly from the insulated transport device may include the step of releasing the anode assembly from the manipulator beam. Then, the method may further include, after releasing the anode assembly from the manipulator beam, raising the manipulator beam into the support structure of the insulated transport device; and removing the insulated transport device from the electrolytic cell.

[0169] As herein, the insulation transport apparatus 100 includes a door assembly 116 for sealing an opening 114 through which the anode assembly enters and leaves the insulation transport apparatus. Then, the method may further include:

[0170] When removing the anode assembly from the anode preconditioner and sealing the anode assembly in an insulated transport device:

[0171] (i) moving the door assembly to an open position;

[0172] (ii) raising the anode assembly into the interior space of an insulated transport apparatus; and

[0173] (iii) closing the door assembly; and

[0174] When installing the anode assembly on the electrolytic cell:

[0175] (i) moving the door assembly to an open position; and

[0176] (ii) lowering the anode assembly from the interior space of the insulated transport device into the electrolytic cell.

[0177] like Fig.11 As shown, once the anode assemblies have been unloaded into the electrolytic cell 40, the box is lifted by the crane 30 to return to the pre-processing station 20 for loading of subsequent anode assemblies.

[0178] Pool Preheater Lifting Beam or CPLB:

[0179] As mentioned above, electrolytic cells operating with inert anodes require preheating, usually using a cell preheater, also referred to herein as a CP. The cell preheater must be inserted into the tank of the cell to preheat the cell, which usually contains the dry electrolyte to be melted, and then removed from the cell before the preheated anodes are introduced into the cell. In addition, even if the inert anodes do not have to be removed from the cell as frequently as consumable carbon anodes, the spent anode assembly (SAA) must be removed from time to time for maintenance and immediately replaced with a new preheated anode assembly (AA). Therefore, the applicant has developed a device called a "cell preheater lifting beam" or CPLB, similar to the transfer box disclosed herein, for safely and accurately inserting the CP into the cell and removing the CP from the cell once the cell is preheated. The CPLB can also be used to remove the spent anode assembly (SAA) from the cell before inserting the new preheated anode assembly into the cell using a transfer box (TB).

[0180] Fig.17 is a schematic diagram of a pool preheater (CP) also developed by the applicant. Pool preheater 200 may include at least one electric heater 210, which includes at least one resistor powered by busbar 220. CP 200 is configured to be installed in an electrolytic cell instead of a corresponding anode assembly, for preheating the cell before the corresponding anode assembly is installed in the cell. As described later herein, busbar 220 may include a connecting element 234 for connecting CPLB to CP and transporting CP. An example of the CP is disclosed in provisional application USSN:63 / 018,680 filed by the applicant with the U.S. Patent Office on May 1, 2020, the contents of which are incorporated herein by reference. Any other type of pool preheater may be used without departing from the scope of the present invention.

[0181] Fig.18 A spent anode assembly (SAA) 50 is shown being moved from an electrolytic cell 40 (left) to a transport vessel outside a maintenance building 60 (right), where the SAA is electrically connected to the cell's equipotential (symbols (+) and (-)).

[0182] Fig.19 The transfer of a cell preheater 200 (CP) from an electrolytic cell 40 (left) to a transport vehicle 60 (right) is shown. Once the cell is heated to the temperature required for the electrolytic reaction, the start-up of the cell requires the removal of the CP. The CP is connected to the upstream (symbol (+)) of the cell isoelectric potential and the downstream (symbol (-)) of the cell isoelectric potential. After removal, the CP is placed on a transport vehicle for transportation outside the building. The CP in the cell is immediately replaced with a new anode assembly, for example by using a transfer box 100 as described herein.

[0183] Fig. 203 is a schematic open view of a CPLB 300 according to a preferred embodiment. The device 300 includes a support structure 310 defining an interior space 312; an actuator assembly 320 is coupled to the support structure 310 and is configured to support an anode assembly or a cell preheater. Fig. 20 As shown, the actuator assembly 320 is operable to be in an isolation position (left) and a load-unload position ( Fig. 20 , right), in the insulated position, the cell preheater or spent anode assembly will be positioned in the interior space 312 of the support structure 310, respectively as shown Fig.21 and 22 and in the loading-unloading position, the anode assembly or cell preheater will be located outside the support structure for loading the anode assembly or cell preheater into or unloading the anode assembly or cell preheater from the actuator assembly.

[0184] According to a preferred embodiment, the actuator assembly 320 of the CPLB includes a horizontal beam 322, which is configured to be detachably connected to the anode assembly and to vertically move the pool preheater or anode assembly within the internal space. The actuator assembly 320 may include a first motor 324 and a second motor 326 supported by the support structure 310, each motor being coupled to a moving element 325, respectively, and the moving element 325 is arranged at the opposite longitudinal ends of the steering beam 322, and the steering beam is vertically raised and lowered along the longitudinal ends. Preferably, for each motor 324, 326, the moving element 325 may include a threaded rod or chain activated by the motor for raising or lowering the steering beam 322.

[0185] like Fig.25 and 26 As shown, the actuator assembly may also include a fail-safe suspension device 330 for removably engaging and supporting the pool preheater ( Fig.26 ) or anode assembly ( Fig.25 ). The fail-safe suspension device 330 for the CPLB can be the same as the fail-safe suspension device 130 of the transfer box described herein. When the actuator assembly is lowered onto the pool preheater or anode assembly, the fail-safe suspension device 330 engages into the corresponding manipulation pin 332 of the pool preheater 200 or the (spent) anode assembly 50.

[0186] Fig.23 is a schematic diagram of a CPLB 300 according to a preferred embodiment, showing the CPLB in its load-unload position with the SAA 50 attached to the steering beam 322 of the actuator assembly 320 (left is a front view, and right is a side view). Fig.24 is a schematic diagram of a CPLB 300 according to a preferred embodiment, showing the CPLB 300 in its loading-unloading position with the CP 200 attached to the handling beam (left is a front view, and right is a side view). Fig.25 is a schematic open view of a CPLB 300 according to a preferred embodiment, wherein the steering beam 322 is in its insulating position, supporting the SAA 50, and Fig.26 is a schematic open view of a CPLB 300 according to a preferred embodiment, wherein the steering beam 322 is in its insulating position, supporting the CP 200.

[0187] like Fig.25 and 26 As shown, the apparatus or CPLB 300 may also include a thermal shield 340 supported by the support structure 310 for protecting the support structure from thermal radiation from the pool preheater or spent anode assembly when the pool preheater or spent anode assembly is removed from the pool. The thermal shield may include a refractory lining. A thermal shield as described above for the transfer box 100 may be used.

[0188] like Figure 25 to Figure 28 As shown, the CPLB 300 also includes an automatic connection system 334, which is configured to electrically connect the cell preheater 200 to the electrolytic cell 40 when the cell preheater is installed in the cell, or to electrically disconnect the cell preheater from the electrolytic cell before being removed from the cell preheater. Figure 25-27 As shown, the CPLB 300 may have two opposing automatic connection systems 334 for electrically connecting the CP 200 to the battery 40 . Fig. 27 2 is a schematic open view of a CPLB 300 supporting a CP 200 on an electrolytic cell, wherein (A) and (B) show details of a pair of automatic connections 334 of the CPLB to the electrolytic cell according to a preferred embodiment. When the CPLB 300 is used to remove and transport SAA, only one of the automatic connection systems 334 is used (see FIG. Fig.26 ), or the CPLB has only one automatic connection system 334, such as Fig.28 shown. Fig.28 is a schematic open view of a CPLB supporting a SAA on an electrolytic cell, wherein (A) details an automated connection of the CPLB to the electrolytic cell according to a preferred embodiment.

[0189] like Fig.25 As shown, the support structure is configured to allow ventilation of the upper zone 313 of the support structure 312 to maintain the upper zone at a lower temperature than the lower hot zone containing the spent anodes of the pool preheater or anode assembly. For example, the upper zone 313 above the beam 322 can be opened to allow natural ventilation of the upper zone 313.

[0190] How to use CPLB

[0191] Figures 29 to 32 The different steps of transporting a CP 200 using a CPLB 300 and installing it in a pool are shown, with the left picture showing a front view and the right picture showing a side view. Fig.29 The first step of bringing the CPLB 300 onto the transport cart 60 containing the CP is shown. Fig.30 The second step of connecting the CPLB 300 to the CP 200 in the transporter 60 is shown. Fig.31 A third step is shown of lifting the CPLB 300 and CP 200 from the transport vehicle 60 prior to transporting the CPLB 300 and CP 200 to the pool 40 to be preheated. Fig.32 4 shows the fourth step of lowering the CP from the CPLB into the electrolytic cell 40 once the CPLB has been positioned above the cell 40. In the second step above, due to the guide pins 318 ( Figure 3 ), placing CPLB precisely on the pool ( Fig.32 ). The electrical connection is accomplished through interaction between the CPLB and the automatic connection system 334 and cooperation with the two electric pods. Fig.32 As shown, multiple CPs 200 can be placed in the same electrolytic cell using CPLB.

[0192] Figures 33 to 36 The different steps of removing and transporting one or more CPs 200 from the pool using the CPLB 300 are shown, with the left figure showing a front view and the right figure showing a side view, once each CP has heated the pool. Fig.33 2 shows the first step of removing the CP 200 from the electrolytic cell 40 once the cell has been heated by the CP. The CPLB 300 is accurately positioned above the electrolytic cell containing the CP with the aid of guide pins 318. Fig.34 As shown, the beam 322 moves downward until the CP is caught and locked with the fail-safe suspension device 330. The two electric pods are disconnected from the CP using the automatic connection system 334. Fig.35 The third step of raising CPLB and CP from the electrolytic cell is shown. Fig.36 The fourth step is shown of lowering and unloading the CP from the CPLB located above the transport vehicle for further transportation and maintenance.

[0193] Figures 37 to 40 The different steps of removing a spent anode assembly (SAA) from a cell 40 using a CPLB 300 are shown, with the left figure showing a front view and the right figure showing a side view. Fig.37 A first step is shown during which the CPLB 300 is precisely positioned over the electrolytic cell 40 containing the SAA using guide pins 318. Fig.38 The second step of removing the SAA from the electrolytic cell is shown, wherein the handling beam 322 of the CPLB 300 is lowered and then the SAA is grasped and locked, as described above for the CP. As described above for the CP, the SAA is disconnected from the cell electricity. Fig.39 The third step of raising the CPLB 300 and SAA 50 from the electrolytic cell 40 is shown. Finally, Fig.40 The fourth step is shown in which the CPLB 300 containing the SAA 50 is positioned above the transport vehicle 60, and the SAA is then lowered and unloaded into the transport vehicle for further transportation and maintenance.

[0194] Fig.41 Different locations of electrical isolation elements of the CPLB according to a preferred embodiment are shown. For the transfer box 100 described herein, the electrical isolation elements 351-354 can be located at different locations of the CPLB 300. Specifically: the first electrical isolation element 351 can be inserted between the support structure 310 and the guide pin 318, the second electrical isolation element 352 can be inserted at the top of the actuator assembly 320, the third electrical isolation element 353 can be inserted between the automatic connection assembly 334 and the support structure 310, and the fourth electrical isolation element 354 can be inserted to isolate the transfer box 100 from the crane, for example, in cooperation with the operating hook 360 on the top of the CPLB. The fourth element 354 can also be part of the main support bridge or crane 30 (see, for example Fig.40 ). A fifth electrical isolation element 355 may be inserted at the bottom surface of the steering beam 322 to avoid any electrical contact or short circuit of the heating resistor of the CP during the connection or disconnection process of the steering beam 322.

[0195] A transfer box (TB) and a cell preheater lifting beam (CPLB) are used in combination to maintain the electrolytic cells.

[0196] Fig.42 is a flow chart showing a method according to a preferred embodiment for starting up and maintaining an electrolytic cell for producing non-ferrous metals, the electrolytic cell being configured to contain N anode assemblies, where N ≥ 1. Typically, a cell may contain up to 17 anode assemblies.

[0197] Method 2000 includes:

[0198] a) 2100: Install N cell preheaters in the cell to replace N anode assemblies;

[0199] b) 2200: preheat the pool using N pool preheaters until a given temperature is reached in the pool;

[0200] c) 2300: pouring the molten electrolytic bath and optionally a portion of the molten metal into the tank;

[0201] d) 2400: removing the first cell pre-heater using an apparatus for transporting an anode assembly or a cell pre-heater outside an electrolytic cell or a CPLB as defined herein;

[0202] e) 2500: using the apparatus or TB for transporting anode assemblies outside an electrolytic cell as defined herein, or according to the method for transporting anode assemblies of inert anodes at a given temperature to an electrolytic cell for the production of non-ferrous metals as defined herein, inserting a preheated anode assembly in place of a removed cell preheater, and

[0203] f) 2600: Repeat steps d) 2400 and e) 2500 (N-1) times until all cell preheaters are replaced with preheated anode assemblies.

[0204] Fig.43 is a flow chart for illustrating a method according to a preferred embodiment for replacing spent anode assemblies of an electrolytic cell during the production of non-ferrous metals, the cell comprising N anode assemblies inserted into an electrolytic bath melted at a given temperature, wherein N ≥ 1. Typically, the given temperature is 750° C. to 1000° C., for example about 850° C., when the electrolyte bath comprises alumina for the manufacture of aluminum.

[0205] The method 3000 includes:

[0206] a) 3100: removing spent anode assemblies from a cell using an apparatus for transporting anode assemblies or a cell preheater outside an electrolytic cell or a CPLB as defined herein;

[0207] b) 3200: immediately after step a), inserting a new anode assembly preheated at a given temperature in place of the removed spent anode assembly, using a device or transfer box for transporting anode assemblies outside an electrolytic cell as defined herein, or according to a method for transporting anode assemblies of inert anodes at a given temperature to an electrolytic cell for the production of non-ferrous metals as defined herein;

[0208] wherein steps a) and b) are carried out while the cell is producing non-ferrous metals, and

[0209] Therein, steps a) and b) are repeated for each spent anode assembly of the cell to be replaced.

[0210] According to a preferred embodiment of the method 2000-3000, the non-ferrous metal is aluminum, and the N anode assemblies include a plurality of inert anodes. More preferably, the inert anodes are vertical inert anodes.

[0211] Advantageously, thermal support of the transfer device or transfer box (TB) allows maintaining anode temperature uniformity and preventing thermal shock when introducing the inert anodes into the thermal electrolysis cell.

[0212] Existing solutions for the conventional Hall-Heroult process are not applicable to the inert anode process due to the different configurations of the cell and anode assembly. Furthermore, they do not answer the limitations associated with preventing thermal shock on the anode. The present invention is compatible with inert anode cell and anode assembly configurations and solves the thermal shock problem.

[0213] In addition, the TB and CPLB according to the present invention are advantageously used in combination to operate an electrolytic cell for starting the cell using a cell preheater and accurately inserting a preheated anode assembly in place of the cell-preheater while maintaining the temperature of the cell and the heated anode assembly, avoiding such thermal shock. The TB and CPLB according to the present invention are advantageously used in combination to replace a spent anode assembly with a new preheated anode assembly while maintaining the other anode assemblies of the cell producing non-ferrous metals. The TB allows for rapid and accurate mechanical and electrical connection of the anode assemblies in the cell, which is an important requirement when inert or oxygen-evolving anodes are used for long periods of time, compared to consumable anodes (e.g., carbon anodes). The CPLB allows for rapid and accurate installation of a cell preheater in the cell, and also allows for rapid and safe removal of the cell preheater or spent anode assembly.

[0214] The description of the present invention is presented for illustrative purposes, but is not intended to be exhaustive or limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected to explain the principles of the invention and its practical application, and to enable others of ordinary skill in the art to understand the invention, so as to implement various embodiments with various modifications that may be suitable for other intended uses.

Claims

1. An apparatus for conveying an anode assembly from an anode pretreatment station outside an electrolytic cell to a molten electrolyte bath of an electrolytic cell, the anode assembly being preheated to a predetermined temperature at the anode pretreatment station, the anode assembly comprising a plurality of inert anodes, the apparatus comprising: a support structure comprising an interior space configured to receive and house the anode assembly; an actuator assembly coupled to the support structure and configured to support the anode assembly, the actuator assembly being operable to move the anode assembly between a thermal isolation position and a load-unload position: In the thermally isolated position, the anode assembly is positioned within the interior space of the support structure; as well as In the load-unload position, the anode assembly is located outside the support structure for loading the anode assembly into or unloading the anode assembly from the actuator assembly; as well as A thermal system is supported by the support structure, wherein the thermal system is configured to maintain a temperature of an inert anode of the anode assembly while the anode assembly is located in the interior space during transport of the anode assembly from the anode pretreatment station to the electrolyte bath.

2. The device according to claim 1, wherein: The actuator assembly also includes an electrical insulation system for electrically isolating the anode assembly from the actuator assembly.

3. The device according to claim 1 or 2, wherein: The support structure defines an open bottom communicating with the interior space, the apparatus further comprising: a door assembly removably coupled to the support structure and operable between an open position allowing the anode assembly to move between the thermally insulating position and the load-unload position and a closed position in which the door assembly closes the open bottom of the support structure.

4. The device according to claim 1 or 2, wherein: The actuator assembly includes a steering horizontal beam configured to be removably connected to the anode assembly and to vertically move the anode assembly within the interior space.

5. The device according to claim 4, wherein: The actuator assembly includes a first motor and a second motor supported by the support structure, each motor being coupled to a moving element disposed at opposite longitudinal ends of the steering horizontal beam, along which the steering horizontal beam is vertically raised and lowered.

6. The device according to claim 5, wherein: The moving element comprises a threaded rod or a chain which is actuated by the motor for raising or lowering the maneuvering level beam.

7. The device according to claim 1 or 2, wherein: The actuator assembly includes a fail-safe suspension arrangement for removably engaging and supporting the anode assembly.

8. The device according to claim 7, wherein: When the actuator assembly is lowered onto the anode assembly, the fail-safe suspension device engages into a corresponding operating pin of the anode assembly.

9. The device according to claim 1 or 2, wherein: The thermal system includes several thermal shields extending from an inner surface of the support structure for engaging respective surfaces of the plurality of anodes when the anode assembly is within the interior space.

10. The device according to claim 9, wherein: The thermal shield comprises a refractory lining.

11. The apparatus of claim 1 or 2, further comprising an electric heater module for heating an inert anode when the anode assembly is in the interior space.

12. The device according to claim 1 or 2, wherein: The support structure is configured to allow ventilation of an upper zone of the anode assembly to maintain the upper zone at a lower temperature than a lower hot zone containing the plurality of anodes.

13. The apparatus of claim 1 or 2, further comprising guide pins that align with structure of the electrolytic cell to facilitate operative installation of the anode assembly in the electrolytic cell.

14. The device according to claim 1 or 2, wherein: The actuator assembly also includes an automatic connection assembly that electrically connects the anode assembly to the electrolytic cell.

15. The device according to claim 14, wherein: The automatic connection assembly includes a pneumatic wrench and a synchronous bolt system.

16. The device according to claim 1 or 2, wherein: The support structure includes an attachment element configured to be mechanically attached to an overhead crane used to transport the apparatus.

17. A method of delivering an anode assembly comprising a plurality of inert anodes at a given temperature to an electrolytic cell for producing non-ferrous metals, comprising: a) preheating the plurality of inert anodes of the anode assembly at the given temperature in a pretreatment station at a distance from the electrolytic cell, the anode assembly being located outside the electrolytic cell; b) removing the anode assembly from the pre-treatment station while the anode assembly is enclosed in an insulated transport device configured to transport the anode assembly toward the electrolytic cell while maintaining the given temperature of the inert anode within a predetermined tolerance range; c) transporting the anode assembly in the insulated transport device toward the electrolytic cell, the insulated transport device comprising a thermal system configured to maintain a given temperature of the preheated inert anode during transport; as well as d) inserting the preheated inert anode of the anode assembly into the molten electrolyte bath of the electrolytic cell.

18. The method according to claim 17, wherein: Removing the anode assembly from the pre-processing station and enclosing the anode assembly in the insulated transport apparatus comprises: positioning the insulated transport apparatus above the anode assembly in an anode preconditioner; lowering an actuator assembly from the interior space of the insulating transport apparatus to the anode assembly; connecting the anode assembly to the actuator assembly; and The actuator assembly with the anode assembly connected thereto is raised from the anode assembly pre-processor into the interior space of the insulating transport apparatus.

19. The method according to claim 18, wherein: Step d) inserting the preheated inert anode of the anode assembly into the molten electrolyte bath of the electrolytic cell comprises: positioning the insulated transport device above the electrolytic cell; lowering the actuator assembly and the anode assembly from the insulated transport device into the electrolytic cell until the preheated inert anode is inserted into the interior of the molten electrolyte bath; mechanically connecting the anode assembly to the electrolytic cell; electrically connecting the inert anode of the anode assembly to the electrolytic cell; and The anode assembly is released from the actuator assembly.

20. The method according to claim 19, wherein: Lowering the anode assembly into the bath includes aligning guide pins of the insulating transport device with corresponding receiving holes of the electrolytic cell, followed by lowering the anode assembly into the electrolytic cell.

21. The method according to claim 19, wherein: Electrically connecting the inert anode of the anode assembly to the electrolytic cell includes mechanically bolting a flexible portion of the anode assembly to an anode equipotential rod of the electrolytic cell.

22. The method according to claim 18, wherein: The actuator assembly is coupled to a support structure of the insulating transport device, the actuator assembly includes a steering beam configured to support the anode assembly and vertically move the anode assembly, wherein releasing the anode assembly from the insulating transport device includes releasing the anode assembly from the steering beam, and the method further includes: After releasing the anode assembly from the handling beam, raising the handling beam into the support structure of the insulated transport apparatus; and The insulated transport device is removed from the electrolytic cell.

23. The method according to claim 17 or 18, wherein: The insulated transport apparatus includes a door assembly for thermally isolating an opening through which the anode assembly enters and exits the insulated transport apparatus, the method further comprising: When the anode assembly is removed from the anode pretreatment station and enclosed in the insulated transport device: (i) actuating the door assembly to an open position; (ii) raising the anode assembly into the interior space of the insulated transport apparatus; and (iii) closing the door assembly; and When the anode assembly is installed at the electrolytic cell: (i) actuating the door assembly to the open position; and (ii) lowering the anode assembly from the interior space of the insulated transport device into the electrolytic cell.

24. An apparatus for transporting a spent anode assembly comprising a plurality of inert anodes or a cell preheater outside an electrolytic cell, the cell preheater being configured to be inserted into the cell to preheat the cell and then inserting the preheated anode assembly into the preheated cell, the apparatus comprising: a support structure, the support structure comprising an interior space; an actuator assembly coupled to the support structure and configured to support the spent anode assembly or the cell preheater, the actuator assembly being operable to move the spent anode assembly or the cell preheater between a thermal isolation position and a load-unload position: In the thermally isolated position, the spent anode assembly or the cell preheater is positioned within the interior space of the support structure; and in the loading-unloading position, the spent anode assembly or the cell preheater is located outside the support structure for loading the spent anode assembly or the cell preheater to the actuator assembly or unloading the spent anode assembly or the cell preheater from the actuator assembly; as well as An automatic connection assembly configured to electrically connect the cell preheater to the electrolytic cell when the cell preheater is installed in the cell, or to electrically disconnect the spent anode assembly or the cell preheater from the electrolytic cell before removal from the electrolytic cell.

25. The apparatus of claim 24, wherein: The actuator assembly further comprises an electrical insulation system for electrically isolating the cell pre-heater or the anode assembly from the actuator assembly.

26. Apparatus according to claim 24 or 25, wherein The actuator assembly includes a steering horizontal beam configured to be detachably connected to the anode assembly and to vertically move the cell pre-heater or the anode assembly within the interior space.

27. The apparatus of claim 26, wherein: The actuator assembly includes a first motor and a second motor supported by the support structure, each motor being connected to a moving element disposed at opposite longitudinal ends of the steering horizontal beam, along which the steering horizontal beam is vertically raised and lowered.

28. The apparatus of claim 27, wherein: The moving element comprises a threaded rod or a chain which is driven by the motor to raise or lower the maneuvering level beam.

29. The apparatus of claim 24 or 25, wherein: The actuator assembly includes a fail-safe suspension arrangement for removably engaging and supporting the cell pre-heater or the anode assembly.

30. The apparatus of claim 29, wherein: When the actuator assembly is lowered onto the pool pre-heater or the anode assembly, the fail-safe suspension device engages into a corresponding operating pin of the pool pre-heater or the anode assembly.

31. The apparatus of claim 24 or 25, further comprising a thermal shield supported by the support structure, the thermal shield being used to protect the support structure from thermal radiation from the pool preheater or the anode assembly when the pool preheater or the anode assembly is removed from the pool.

32. The apparatus of claim 31, wherein: The thermal shield comprises a refractory lining.

33. The apparatus of claim 24 or 25, wherein: The support structure is configured to allow ventilation of an upper region of the support structure to maintain the upper region at a lower temperature than a lower hot region containing the cell preheater or the anodes of the anode assembly.

34. The apparatus of claim 24 or 25, further comprising guide pins that align with structure of the electrolytic cell to facilitate operative installation of the cell preheater or the anode assembly in the electrolytic cell.

35. The apparatus of claim 24 or 25, wherein: The automatic connection assembly includes a pair of pneumatic wrenches and a synchronized bolt system.

36. The apparatus of claim 24 or 25, wherein: The support structure includes an attachment element configured to be mechanically attached to an overhead crane used to transport the apparatus.

37. A method for starting up an electrolytic cell for producing non-ferrous metals, the electrolytic cell being configured to contain N anode assemblies, wherein N ≥ 1, the method comprising: a) installing N cell preheaters in said cell in place of said N anode assemblies; b) preheating the pool with the N pool preheaters until a given temperature is reached in the pool; c) pouring a molten electrolytic bath and a certain amount of molten metal into the tank; d) removing the first cell pre-heater using an apparatus for transporting spent anode assemblies or cell pre-heaters outside an electrolytic cell as defined in any one of claims 24 to 36; e) using an apparatus for transporting anode assemblies outside an electrolytic cell as defined in any one of claims 1 to 16, or a method for transporting anode assemblies of inert anodes at a given temperature to an electrolytic cell as defined in any one of claims 17 to 23, inserting the preheated anode assemblies in place of the removed cell preheater, and f) Repeating steps d) and e) (N-1) times until all said cell preheaters are replaced by preheated anode assemblies.

38. The method of claim 37, wherein: The non-ferrous metal is aluminum, and the N anode assemblies include a plurality of inert anodes.

39. The method of claim 38, wherein: The inert anode is a vertical inert anode.

40. A method of replacing spent anode assemblies of an electrolytic cell in a non-ferrous metal production process, the cell comprising N anode assemblies inserted into a molten electrolytic bath at a given temperature, wherein N ≥ 1, the method comprising: a) removing the spent anode assembly from the cell using an apparatus for transporting anode assemblies or cell preheaters outside an electrolytic cell as defined in any one of claims 24 to 36; b) immediately after step a), inserting a new anode assembly preheated at a given temperature to replace the removed spent anode assembly, using an apparatus for transporting anode assemblies outside an electrolytic cell as defined in any one of claims 1 to 16, or a method as defined in any one of claims 17 to 23, wherein steps a) and b) are performed when the cell produces non-ferrous metals, and Therein, steps a) and b) are repeated for each spent anode assembly of the cell to be replaced.

41. The method of claim 40, wherein: The non-ferrous metal is aluminum, and the N anode assemblies include a plurality of inert anodes.

42. The method according to claim 41, wherein: The inert anode is a vertical inert anode.

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