Single optical fiber ring-based current measurement unit for electrolyzer zone, and electrolyzer measurement system

Abstract

A single optical fiber ring-based current measurement unit for an electrolyzer zone, and an electrolyzer measurement system. The electrolyzer zone comprises a column busbar (7), two horizontal busbars (3-A, 3-B), two rows of anode conducting rods (2), and two rows of anodes (1), wherein the column busbar (7) is electrically connected to the two horizontal busbars (3-A, 3-B), the column busbar (7) transmitting a current to the two horizontal busbars (3-A, 3-B); each of the horizontal busbars (3-A, 3-B) is electrically connected to the anodes (1) by means of a corresponding row of anode conducting rods (2), the horizontal busbars (3-A, 3-B) being in contact with each anode conducting rod (2) and having an electrically conductive portion severing as the electrical connection portion of the two; and an optical fiber sensing ring of one optical fiber current sensor (5) encloses the electrical connection portion of at least one anode conducting rod (2) and the horizontal busbars (3-A, 3-B), a current value measured by the optical fiber current sensor (5) being the sum of anode currents of the anodes (1) corresponding to electrical connection portions within the optical fiber sensing ring. The use of a single optical fiber current sensor (5) enables accurate on-line measurement of the anode current in the electrolyzer zone, so that the measurement cost is significantly reduced; the accuracy and current efficiency are high; and energy saving, consumption reduction, and emission reduction are realized.

Description

Electrolytic cell area current measurement unit and electrolytic cell measurement system based on single optical fiber ring

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on the application with Chinese application number 202310948786.9 and application date July 31, 2023, and claims its priority. The disclosed content of the Chinese application is hereby introduced as a whole into this application. Technical Field

[0003] The present invention relates to the technical field of current measurement, and in particular to an electrolytic cell area current measurement unit and an electrolytic cell measurement system based on a single optical fiber ring. Background Art

[0004] The electrolytic cell control system determines the change in electrolyte pseudo-resistance based on the series current and cell voltage to control the alumina concentration. In the electrolytic cell, alumina is added in a regional manner. Therefore, the electrolytic cell is divided into multiple zones, each of which is equipped with a column busbar and 8 anodes. The magnitude of the anode current in the zone directly determines the amount of alumina participating in the reaction in that zone, that is, the amount of alumina consumed. Due to the influence of production operations such as pole changing and aluminum tapping, the anode current in each zone will vary significantly. If a unified feeding strategy is implemented for each zone based on the pseudo-resistance information of the entire cell, it will lead to frequent inaccurate feeding problems. Accurately measuring the anode current in the electrolytic cell zone is of great practical significance for the production process control of aluminum electrolytic cells.

[0005] In order to accurately measure the anode current value of each area, a solution for measuring the anode current of an aluminum electrolytic cell is provided in the prior art. For example, the system for measuring the anode current of an aluminum electrolytic cell disclosed in CN 108998813 A includes: multiple electrolytic cell units; the electrolytic cell units include: 1 vertical busbar, 2 horizontal busbars, m anodes, m anode guide rods, 1 or 1 pair of jumper busbars and multiple optical fiber current sensors; the m anode guide rods and the m anodes are divided into two rows, A and B, one end of the anode guide rods in each row is respectively overlapped on each horizontal busbar, and the other end of the anode guide rods in each row is respectively connected to the anodes in each row, each anode is arranged in a one-to-one correspondence with each anode guide rod, the jumper busbar is arranged on one side or both sides of the feed port, and the two horizontal busbars are connected by The jumper busbar is connected, and one end of the column busbar is connected to the first horizontal busbar; when one side of the anode guide rod is adjacent to another anode guide rod, a fiber optic current sensor is set on the horizontal busbar between the two anode guide rods; when any side of the anode guide rod is adjacent to the column busbar or the jumper busbar, a fiber optic current sensor is set on the horizontal busbar between the anode guide rod and the column busbar or the jumper busbar; when any side of the anode guide rod is neither adjacent to the anode guide rod nor to the column busbar or the jumper busbar, there is no need to set a fiber optic current sensor on the horizontal busbar on that side.

[0006] Through the above scheme, multiple fiber optic current sensors are used to measure the anode current of an area. Because the fiber optic current sensors are symmetrically mounted on the anode guide rods and cathode guide rods, basically a fiber optic current sensor is set between every two adjacent anode guide rods and between every two cathode guide rods, which makes the entire measurement system costly and not conducive to implementation.

[0007] Summary of the Invention

[0008] The purpose of the present invention is to provide an electrolytic cell area current measurement unit and an electrolytic cell measurement system based on a single optical fiber ring, so as to achieve accurate measurement of the electrolytic cell area current at a lower cost.

[0009] In a first aspect, the technical solution of the present application provides an electrolytic cell area current measurement unit based on a single optical fiber ring, wherein the electrolytic cell area includes a column busbar, two horizontal busbars, two rows of anode guide rods, and two rows of anodes, wherein the column busbar is electrically connected to the two horizontal busbars, and the column busbar transmits current to the two horizontal busbars; each of the horizontal busbars is electrically connected to the anode through a corresponding row of anode guide rods, and the current on the horizontal busbar is input to the corresponding anode after passing through the anode guide rod, and the conductive portion of the horizontal busbar in contact with each anode guide rod is the electrical connection portion between the two; and further comprising:

[0010] A fiber optic current sensor, wherein the fiber optic sensing ring of the fiber optic current sensor surrounds the electrical connection part between at least one of the anode guide rods and the horizontal busbar, and the current value detected by the fiber optic current sensor is the sum of the anode currents of the anodes corresponding to the electrical connection parts within the fiber optic sensing ring.

[0011] In some schemes, the electrolytic cell area current measurement unit based on a single optical fiber ring is described, wherein the optical fiber sensing ring of the optical fiber current sensor surrounds the electrical connection portion between an anode guide rod in the electrolytic cell area and the horizontal busbar, so that the current passing through the anode guide rod passes through the optical fiber sensing ring.

[0012] In some schemes, the electrolytic cell area current measurement unit based on a single optical fiber ring is described, wherein the optical fiber sensing ring of the optical fiber current sensor surrounds the electrical connection parts of all the anode guide rods in the electrolytic cell area and the horizontal busbar, so that the current passing through all the anode guide rods passes through the optical fiber sensing ring.

[0013] In some embodiments of the electrolytic cell area current measurement unit based on a single optical fiber ring, the optical fiber sensing ring of the one optical fiber current sensor spans the lower edges of the two horizontal busbars between two adjacent electrolytic cell areas.

[0014] In some schemes, the electrolytic cell area current measurement unit based on a single optical fiber ring is described. If adjacent electrolytic cell areas are set on both sides of the electrolytic cell area, then the optical fiber sensing ring of the one optical fiber current sensor, the optical fiber part located outside the two horizontal busbars is folded and placed on the upper part of the corresponding horizontal busbar, and bypasses the lower part of the connection section between the column busbar and a horizontal busbar.

[0015] In some schemes, the electrolytic cell area current measurement unit based on a single optical fiber ring is described. If the electrolytic cell area is located at the aluminum outlet end or the flue end, the optical fiber sensing ring of the one optical fiber current sensor is located at one end of the aluminum electrolytic cell, and the optical fiber sensing ring passes directly over the two horizontal busbars after bypassing the lower part of the connection section between the column busbar and the horizontal busbar.

[0016] The electrolytic cell area current measurement unit based on a single optical fiber ring according to some embodiments further comprises:

[0017] The optical fiber protection tube has a connecting optical fiber disposed therein; the connecting optical fiber is used to transmit the current information detected by the optical fiber sensing ring to the measuring box for analysis and processing by the measuring box.

[0018] In a second aspect, the technical solution of the present application further provides an electrolytic cell measurement system, comprising an electrolytic cell, wherein the electrolytic cell comprises a plurality of electrolytic cell areas and a fiber optic current sensor;

[0019] A fiber optic sensing ring of the fiber optic current sensor is used to enclose the electrical connection part between at least one anode guide rod and the horizontal busbar in at least one electrolytic cell area. The current value detected by the fiber optic current sensor is the sum of the anode currents of the anodes corresponding to each of the electrical connection parts in the fiber optic sensing ring.

[0020] In the electrolytic cell measurement system described in some embodiments, the anode guide rod surrounded by the optical fiber sensing ring belongs to two adjacent electrolytic cell areas.

[0021] In some embodiments of the electrolytic cell measurement system, the anode guide rod surrounded by the optical fiber sensing ring belongs to two non-adjacent electrolytic cell areas;

[0022] The remaining electrolytic cell area between the two non-adjacent electrolytic cell areas uses a fiber optic sensing ring of another fiber optic current sensor to surround the electrical connection portion between at least one anode guide rod in the remaining electrolytic cell area and the horizontal busbar.

[0023] In the electrolytic cell measurement system described in some schemes, the number of the electrolytic cell areas and the optical fiber current sensors is the same and has a corresponding relationship, and one optical fiber current sensor is used to enclose the electrical connection parts of all anode guide rods and horizontal busbars in the corresponding electrolytic cell area.

[0024] In the electrolytic cell measurement system described in some schemes, when the number of electrolytic cell areas is N, the number of the fiber optic current sensors is (N-1); wherein: the (N-1) fiber optic current sensors correspond to the (N-1) electrolytic cell areas, and one fiber optic current sensor is used to enclose all the electrical connection parts of the anode guide rods and the horizontal busbar of the corresponding electrolytic cell area inside it; the anode current of the Nth electrolytic cell area is determined based on the total current of the electrolytic cell and the detection current of the (N-1) fiber optic current sensors.

[0025] Compared with the prior art, the above solution provided by this application has at least the following beneficial effects:

[0026] The present invention provides an electrolytic cell area current measurement unit and electrolytic cell measurement system based on a single optical fiber ring. The electrolytic cell area includes a column busbar, two horizontal busbars, two rows of anode guide rods, and two rows of anodes. The column busbar is electrically connected to the two horizontal busbars, and the column busbar transmits current to the two horizontal busbars. Each horizontal busbar is electrically connected to the anode through a corresponding row of anode guide rods. The conductive portion of the horizontal busbar in contact with each anode guide rod is the electrical connection portion between the two. A fiber optic current sensor's optical fiber sensing ring surrounds the electrical connection portion between at least one anode guide rod and the horizontal busbar. The current value detected by the optical fiber current sensor is the sum of the anode currents of the anodes corresponding to each electrical connection portion within the optical fiber sensing ring. The present invention uses a single optical fiber current sensor to accurately detect the anode current of the electrolytic cell area online, significantly reducing measurement costs, achieving high accuracy, high current efficiency, and energy saving, consumption reduction, and emission reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0028] FIG1 is a schematic diagram of the principle of a fiber optic current sensor;

[0029] FIG2 is a schematic structural diagram of an electrolytic cell region current measurement unit based on a single optical fiber ring according to an embodiment of the present application;

[0030] FIG3 is a diagram showing a measurement of a single anode current using a single optical fiber sensing ring according to an embodiment of the present application;

[0031] FIG4 is a schematic diagram of a current transmission path for transmitting current from a column busbar to each anode according to an embodiment of the present application;

[0032] FIG5 is a schematic structural diagram of an electrolytic cell region current measurement unit based on a single optical fiber ring according to another embodiment of the present application, wherein there are adjacent electrolytic cell regions on both sides of the electrolytic cell region;

[0033] FIG6 is a schematic structural diagram of an electrolytic cell region current measurement unit based on a single optical fiber ring according to another embodiment of the present application, wherein one side of the electrolytic cell region is an aluminum outlet end;

[0034] FIG7 is a schematic structural diagram of an electrolytic cell measurement system according to an embodiment of the present application;

[0035] FIG8 is a schematic structural diagram of an electrolytic cell measurement system according to another embodiment of the present application. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0037] The purpose of the present invention is to provide a system for measuring the anode current of an aluminum electrolytic cell area, so as to achieve online and accurate measurement of the anode current of each electrolytic cell area.

[0038] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] Due to the complexity of industrial aluminum reduction cells, using a single fiber optic current sensor to measure anode current in a specific area requires a special installation method to avoid affecting anode operation. To facilitate understanding, this article first introduces the principles of current measurement using fiber optic current sensors and the approach to using fiber optic current sensors to measure anode current in a specific area of ​​an aluminum reduction cell.

[0040] Figure 1 illustrates the principle of current measurement using a fiber-optic current sensor. The entire measurement system comprises an optical signal module G1, a connecting optical fiber G2, a wave plate G3, a reflector G4, and a sensing fiber ring G5, which is attached to the outside of conductor B. When the sensing fiber ring G5 forms a closed loop around conductor B—that is, when reflector G4 and glass plate G3 are closed—the current measured by the fiber-optic current sensor is the total current flowing through conductor B within the sensing fiber ring G5. This current is independent of the current or magnetic field in the conductor outside the ring, or the shape of the conductor within the ring. Furthermore, as long as the sensing fiber ring forms a closed loop, its shape is irrelevant.

[0041] Based on the measurement principle of a fiber optic current sensor, the anode current of an aluminum electrolysis cell area can be measured as shown in Figure 2. Specifically, a fiber optic sensing ring 5 is used to surround the eight anode columns, with the eight anode guide rods acting as a conductor running through the fiber optic sensing ring 5 (i.e., as conductor B in Figure 1). Thus, the current passing through the eight anode guide rods can be detected using a fiber optic current sensor. In practical applications, the structure shown in Figure 2 may make it difficult to secure the fiber optic sensing ring 5. To address this, the structure shown in Figure 3 can be used to secure the fiber optic sensing ring 5 between the anode guide rods and the horizontal busbar. Specifically, a fiber optic sensing ring 5 is used to wrap around the electrical connection between the horizontal busbar 3-A and the anode guide rod 2, forming a closed loop. This allows the current conducted through the column busbar 7 to the horizontal busbar 3-A, then to the anode guide rod 2, and ultimately to the corresponding anode to be measured without affecting the anode replacement process. As shown in Figure 4, taking the A-row structure in a single area as an example, after the current from the vertical busbar is transmitted to the horizontal busbar 3-A, it propagates along the horizontal busbar 3-A toward both sides of the vertical busbar. After reaching the electrical connection between the horizontal busbar 3-A and the anode guide rod, the current propagates along the anode guide rod toward the anode. Based on the above current flow direction, it can be unequivocally determined that measuring the current in the electrical connection between the anode guide rod and the horizontal busbar 3-A is equivalent to measuring the current in the anode guide rod. Based on this principle, the fiber optic sensing ring surrounding the anode guide rod shown in Figure 2 can be adjusted to surround the electrical connection between the anode guide rod and the horizontal busbar as shown in Figure 3. That is, by measuring the current value in the electrical connection, the current value of the anode guide rod, and thus the anode current value, can be obtained. Similarly, as shown in Figure 5, a fiber optic sensing ring 5 is used to surround the electrical connection between the eight anode guide rods 2 in a single area and the horizontal busbars 3-A and 3-B. The current flowing through the eight anode guide rods 2 in the corresponding area can then be measured. Similarly, FIG6 to FIG8 also realize the corresponding regional anode current measurement.

[0042] The following is a detailed introduction to the system and measurement process of this solution.

[0043] The present application provides an electrolytic cell zone current measurement unit based on a single optical fiber ring. As shown in Figures 2-8 , an aluminum electrolytic cell comprises multiple electrolytic cell zones, each corresponding to an alumina feeder. The zones are connected by two horizontal busbars 3-A and 3-B. Figure 2 shows an electrolytic cell zone i, which comprises: one vertical busbar 7, two horizontal busbars 3-A and 3-B, eight anodes 1, eight anode guide rods 2, and a pair of jumper busbars 6. The 8 anode guide rods 2 and the 8 anodes 1 in the electrolytic cell area i are divided into two rows A and B. One end of the anode guide rods 2 in each row is respectively overlapped on the corresponding horizontal busbars 3-A and 3-B in rows A and B, and the other end of the anode guide rods 2 in each row is respectively connected to the anodes 1 in each row. Each anode 1 is arranged in one-to-one correspondence with each anode guide rod 2. The two horizontal busbars 3-A and 3-B are connected by the jumper busbar 6, and one end of the column busbar 7 is connected to the A horizontal busbar 3-A.

[0044] In this solution, the current of a single anode in the region is measured using a single fiber optic sensing ring 5. As shown in Figure 3, a fiber optic sensing ring 5 wraps the electrical connection between an anode guide rod 2 in the electrolytic cell region and the horizontal busbar 3-A on the A side within a closed loop (as shown in the figure, showing the positional relationship between the second anode guide rod and the fiber optic sensing ring). This allows the current flowing through the anode in the region to pass through the fiber optic sensing ring 5, creating a system that uses a single fiber optic sensing ring 5 to measure the current of a single anode, thereby achieving precise measurement of the anode current.

[0045] As shown in Figure 5 , when an electrolytic cell region is flanked by adjacent electrolytic cell regions, for example, when the i-th electrolytic cell is flanked by the (i-1)th and (i+1)th electrolytic cells, a single fiber optic sensing ring 5 is used to connect the electrical connections between the anode guide rods of the eight anodes in the electrolytic cell region and the horizontal busbars 3-A and 3-B in rows A and B. This means that the electrical connections between the anode guide rods of the eight anodes and the horizontal busbars 3-A and 3-B in rows A and B are all located within the fiber optic sensing ring 5 . This allows the currents flowing through the eight anodes in the region to pass through the fiber optic sensing ring 5 , creating a system that uses a single fiber optic sensing ring 5 to measure the currents of all eight anodes in a single region, thereby achieving accurate measurement of the currents of all anodes in the region. Comparing Figure 5 with Figure 2 , Figure 5 is obtained by folding upward the portion of the fiber optic sensing ring 5 in Figure 2 that is close to the column busbar 7. The fiber optic sensing ring below the column busbar 7 remains below the column busbar, bypassing the column busbar.

[0046] As shown in Figure 6, the electrolytic cell area is located on the side of the aluminum tapping end. Comparing Figures 2 and 6, it is actually obtained by folding the portion of the optical fiber sensing ring located on the side of the aluminum tapping end in Figure 2 to the outside of the horizontal busbar. At this time, the sum of the currents in the electrical connection parts corresponding to the two anodes A11 and A12 on the side of the aluminum tapping end corresponds to the current passing through the right part of the column busbar. Therefore, in this solution, the sum of the currents of anodes A11 and A12 can be obtained by directly surrounding the horizontal busbar on the right side of the column busbar. Based on a similar principle, if there are no other electrolytic cell areas on the left side of the electrolytic cell area, the optical fiber sensing ring on the left side can also measure the current on the horizontal busbar on the left side of the column busbar. Combined with Figure 4, this current value is equal to the sum of the currents of anodes A13 and A14.

[0047] Based on the above analysis, the present application solution requires only one fiber optic current sensor to detect the anode current in the electrolytic cell area of ​​an aluminum electrolytic cell. Specifically, as long as the fiber optic sensing ring of the fiber optic current sensor encloses the electrical connection between at least one anode guide rod and the horizontal busbar, the current value detected by the fiber optic current sensor is the sum of the anode currents of the anodes corresponding to each of the electrical connections within the fiber optic sensing ring. As shown in Figure 2, all eight anode guide rods in the electrolytic cell area are placed within a single fiber optic sensing ring.

[0048] In order to better understand the technical solutions of the present invention, the solutions in the following specific embodiments are described with reference to the accompanying drawings.

[0049] Example 1

[0050] As shown in Figure 3, the electrolytic cell area includes 1 column busbar 7, 2 horizontal busbars 3-A and 3-B, 12 anodes 1, 12 anode guide rods 2, a pair of jumper busbars 6, and an optical fiber sensing ring 5 of an optical fiber current sensor. The 12 anode guide rods 2 and the 12 anodes 1 are divided into 2 rows, namely row A and row B. One end of the anode guide rods 2 in each row is respectively overlapped on the corresponding horizontal busbars 3-A and 3-B, and the other end of the anode guide rods 2 in each row is respectively connected to the anodes 1 in each row. Each anode 1 is arranged in a one-to-one correspondence with each anode guide rod 2. The jumper busbars 6 are respectively arranged on both sides of the feed port. The two horizontal busbars 3-A and 3-B are connected by the jumper busbar 6. One end of the column busbar 7 is connected to the A horizontal busbar 3-A. The current is transmitted from the vertical busbar 7 to the horizontal busbar 3-A connected thereto. Approximately half of the current passes through the horizontal busbar 3-A and is then transmitted to the corresponding anodes 1 via the anode guide rods 2 connected to the horizontal busbar 3-A. Approximately half of the current passes through the jumper busbar 6 to the B horizontal busbar 3-B, and then passes through the horizontal busbar 3-B and is then transmitted to the corresponding anodes 1 via the anode guide rods 2 connected thereto. The fiber optic sensing ring 5 is placed against the horizontal busbar 3-A, with its lower and upper edges bent inwardly toward the horizontal busbar 3-A to ensure that the anode guide rods of the anodes to be measured, which are hung on the horizontal busbar 3-A, are within the fiber optic ring. In this way, the current transmitted from the horizontal busbar 3-A to the anode guide rods passes through the closed fiber optic sensing ring 5, achieving current measurement.

[0051] Example 2

[0052] As shown in Figure 5, the electrolytic cell area i includes: 1 column busbar 7, 2 horizontal busbars 3-A and 3-B, 8 anodes 1, 8 anode guide rods 2, 1 pair of jumper busbars 6, and 1 optical fiber current sensor 5; there will also be adjacent electrolytic cell areas (i-1) and (i+1) on its left and right sides. The 8 anode guide rods 2 and the 8 anodes 1 are divided into 2 rows, namely row A and row B. The first anode 2 in row A is represented by Ai1, the first anode 2 in row B is represented by Bi1, and the others are similar. They will not be discussed one by one here. A total of 8 anodes, namely Ai1~Ai4, Bi1~Bi4, constitute the electrolytic cell area i. One end of the anode guide rods 2 in each row is respectively overlapped on each horizontal busbar 3-A and 3-B, and the other end of the anode guide rods 2 in each row is respectively connected to the anode 1 in each row. Each anode 1 is arranged in a one-to-one correspondence with each anode guide rod 2. The jumper busbar 6 is respectively arranged on both sides of the feed port. The two horizontal busbars 3-A and 3-B are connected by the jumper busbar 6, and one end of the column busbar 7 is connected to the A horizontal busbar 3-A. The current is transmitted from the column busbar 7 to the horizontal busbar 3-A connected thereto, and about half of the current passes through the horizontal busbar 3-A to transmit the current to the corresponding anodes 1 through the anode guide rod 2 overlapped with the horizontal busbar 3-A. About half of the current is transmitted through the jumper busbar 6 to the B horizontal busbar 3-B, and then passes through the horizontal busbar 3-B to transmit the current to the corresponding anodes 1 through the anode guide rod 2 overlapped with it.

[0053] As shown in the figure, the fiber optic sensor loop 5 passes beneath horizontal busbars 3-A and 3-B outside Ai1-Bi1 and Ai4-Bi4. It then rises outside horizontal busbars 3-A and 3-B to the upper edges of those busbars, as shown in Figure 5. However, it descends again at the junction of upright busbar 7 and horizontal busbar 3-A, passing beneath the junction. This allows for uninterrupted operation during the electrolysis process, such as anode reversal and horizontal busbar raising and lowering.

[0054] Based on the principle of the Faraday magneto-optical effect, which deflects light in a magnetic field, a closed-loop optical path method is used to effectively overcome interference from background magnetic fields and contact, resulting in high measurement accuracy. Furthermore, the fiber optic sensing ring 5 of the fiber optic current sensor transmits optical signals. The conductive medium is optical fiber, which is naturally electrically insulating, safe, reliable, and flexible. It is easily installed according to the special structure shown in FIG5 , without affecting the pole-changing operation and horizontal busbar lifting and lowering operations during the electrolytic production process. It can accurately measure the anode current in each electrolytic cell area with a measurement accuracy of less than 0.5%, enabling on-demand addition of alumina to the electrolytic cell area and diagnosis of the anode status of the electrolytic cell area. This ensures stable and efficient production in the electrolytic cell area, significantly improving current efficiency, reducing energy consumption, and achieving energy conservation and emission reduction for aluminum electrolytic cells.

[0055] Example 3

[0056] As shown in Figure 6, this area includes a total of 8 anodes, namely A11 to A14 and B11 to B14. The difference from Example 1 is that when the measurement area is located at the aluminum outlet end or the flue end, such as the aluminum outlet end shown in Figure 6, the aluminum outlet end portion of an optical fiber sensing ring 5 can be passed under the connection section between the column busbar 7 and the horizontal busbar 3-A as shown in Figure 6, and then directly cross the upper part of the horizontal busbars 3-A and 3-B between the column busbar and A12. This can save optical fiber rings and simplify the installation structure of the optical fiber sensor. It also does not affect the pole changing operation and the horizontal busbar lifting and lowering operation of the electrolytic production, and can accurately measure the anode current of each electrolytic cell area with a measurement accuracy of within 0.5%.

[0057] Some embodiments of the present application provide an electrolytic cell measurement system, comprising an electrolytic cell comprising multiple electrolytic cell zones: at least one of the electrolytic cell zones employs the electrolytic cell zone current measurement unit based on a single optical fiber ring provided in any of the aforementioned embodiments. For example, all of the electrolytic cell zones employ the electrolytic cell zone current measurement unit based on a single optical fiber ring. Alternatively, some adjacent electrolytic cell zones employ the electrolytic cell zone current measurement unit based on a single optical fiber ring, and the adjacent electrolytic cell zones are grouped together for alumina dosing control.

[0058] The electrolytic cell measurement system, shown in Figure 7, is designed to simultaneously measure the anode currents of two adjacent zones, Ri and R(i+1), using a single fiber optic sensing loop. As shown, the sensing fiber simultaneously surrounds the 16 anodes in two adjacent electrolytic cell zones to form a closed loop. The fiber optic sensing loop also passes underneath the connection between the vertical busbar and the horizontal busbar 3-A at both vertical busbars. This allows for grouped measurement of electrolytic cell currents and control of alumina dosing.

[0059] As shown in Figure 8, this solution uses a single fiber optic sensing loop to simultaneously measure the anode currents of two non-adjacent regions, Ri and R(i+2). The loop forms a closed loop around the 16 anodes in both regions. When passing through the middle region, R(i+1), the loop passes under the horizontal busbars in rows A and B of region R(i+1), bypassing the inside of each of the four anode guide rods attached to the two horizontal busbars. This allows a single fiber optic sensing loop to measure the anode currents of non-adjacent electrolytic cell regions online. This approach enables grouped measurement of the current in each electrolytic cell region and grouped control of alumina addition.

[0060] As an achievable approach, in the electrolytic cell measurement system, the electrolytic cell zones and the fiber optic current sensors are equal in number and correspond to each other. One fiber optic current sensor is configured to enclose within its interior all of the electrical connections between the anode guide rods and the horizontal busbar in the corresponding electrolytic cell zone. For example, if an electrolytic cell is divided into six electrolytic cell zones, and each zone uses a fiber optic current sensor to measure the anode current, then six fiber optic current sensors are included. The fiber optic sensing ring of each fiber optic current sensor can enclose the electrical connection between the anode guide rods and the horizontal busbar in the manner shown in Figures 5 or 6. Thus, each fiber optic current sensor is capable of measuring the anode current of one electrolytic cell zone.

[0061] As another achievable embodiment, when the number of electrolytic cell regions is N, the number of fiber optic current sensors is (N-1); wherein: the (N-1) fiber optic current sensors correspond to the (N-1) electrolytic cell regions, and one fiber optic current sensor is used to enclose the electrical connection portions between all anode guide rods and the horizontal busbar in the corresponding electrolytic cell region; the anode current of the Nth electrolytic cell region is determined based on the total electrolytic cell current and the detection currents of the (N-1) fiber optic current sensors. For example, if an electrolytic cell is divided into six electrolytic cell regions, and five of the electrolytic cell regions use one fiber optic current sensor to measure their anode currents, then five fiber optic current sensors are included. The fiber optic sensing ring of each fiber optic current sensor can enclose the electrical connection portion between the anode guide rod and the horizontal busbar in the manner shown in FIG5 or FIG6. Thus, each fiber optic current sensor can measure the anode current of one electrolytic cell region, and the anode currents of five electrolytic cell regions can be measured using the fiber optic current sensors. The total input current of the electrolytic cell is known or measurable. By subtracting the anode currents of five electrolytic cell zones from the total input current, the anode current of the last electrolytic cell zone can be obtained. Based on this principle, in the aforementioned embodiment, when the number of electrolytic cell zones and the fiber optic current sensors is the same and corresponds to each other, if one fiber optic current sensor fails and cannot function normally, this solution can also be adopted to determine the anode current of the remaining electrolytic cell zones using only the relationship between the detection results of (N-1) fiber optic current sensors and the total input current. The present invention uses a single fiber optic current sensor to accurately detect the anode current of an independent electrolytic cell zone, providing accurate data for adding alumina based on the alumina consumption of the electrolytic cell zone, avoiding imbalances in anode current distribution and alumina demand caused by conventional pole-changing operations. By accurately detecting the anode current of an independent electrolytic cell zone, status information of each feeding point zone can be obtained, including alumina concentration, local pole distance, and local faults. Accurately detecting the anode current of an independent electrolytic cell zone can predict local condition trends and faults, thereby achieving health management of the entire electrolytic cell. Using a single fiber optic current sensor to accurately measure the anode current in individual electrolyzer zones significantly reduces the number of sensors used in the electrolyzer. This improves measurement accuracy, achieves higher current efficiency, and enables electrolysis at lower voltages. Accurately measuring the anode current in individual electrolyzer zones allows for the prediction and diagnosis of faults occurring in each zone. This precise measurement of the anode current in individual electrolyzer zones allows for timely identification and treatment of local effects, thereby eliminating the anode effect and reducing greenhouse gas emissions.

[0062] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the common and similar parts between the various embodiments. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method description.

[0063] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A regional anode current measurement system based on a single optical fiber ring, used for measuring the anode current of an electrolytic cell area, wherein the electrolytic cell area comprises a column busbar, two horizontal busbars, two rows of anode guide rods and two rows of anodes, wherein the column busbar is electrically connected to the two horizontal busbars, and the column busbar transmits current to the two horizontal busbars; each of the horizontal busbars is electrically connected to the anode through a corresponding row of anode guide rods, and the current on the horizontal busbar is input to the corresponding anode after passing through the anode guide rods, and the conductive portion of the horizontal busbar in contact with each anode guide rod is the electrically connected portion of the two; and further comprising: A fiber optic current sensor, wherein the fiber optic sensing ring of the fiber optic current sensor surrounds the electrical connection portion between at least one of the anode guide rods and the horizontal busbar, and the current value detected by the fiber optic current sensor is the sum of the anode currents of the anodes corresponding to the electrical connection portions in the fiber optic sensing ring; wherein: The optical fiber sensing ring of the optical fiber current sensor surrounds the electrical connection parts of all anode guide rods in the electrolytic cell area and the horizontal busbar, so that the current passing through all anode guide rods passes through the optical fiber sensing ring.

2. The regional anode current measurement system based on a single optical fiber ring according to claim 1, wherein: The optical fiber sensing loop of the optical fiber current sensor spans over the lower edges of the two horizontal busbars between two adjacent electrolytic cell areas.

3. The regional anode current measurement system based on a single optical fiber ring according to claim 2, wherein: If adjacent electrolytic cell areas are set on both sides of the electrolytic cell area, the optical fiber sensing ring of the optical fiber current sensor is located outside the two horizontal busbars, and the optical fiber portion is folded and placed on the upper part of the corresponding horizontal busbar, and bypasses the lower part of the connection section between the column busbar and one of the horizontal busbars.

4. The regional anode current measurement system based on a single optical fiber ring according to claim 2 or 3, wherein: If the electrolytic cell area is located at the aluminum outlet end or the flue end, the optical fiber sensing ring of the optical fiber current sensor is located at one end of the electrolytic cell, and the optical fiber sensing ring bypasses the lower part of the connection section between the column bus and the horizontal bus and directly crosses over the two horizontal bus bars.

5. The regional anode current measurement system based on a single optical fiber ring according to any one of claims 1 to 4, further comprising: An optical fiber protection tube, inside which a connecting optical fiber is arranged; The connecting optical fiber is used to transmit the current value detected by the optical fiber sensing ring to the measuring box for analysis and processing by the measuring box.

6. An electrolytic cell measurement system, characterized in that: An electrolytic cell and a fiber optic current sensor are included, wherein the electrolytic cell includes a plurality of electrolytic cell areas; A fiber optic sensing ring of the fiber optic current sensor is used to surround the electrical connection portion between at least one anode guide rod and the horizontal busbar in at least one electrolytic cell area, and the current value detected by the fiber optic current sensor is the sum of the anode currents of the anodes corresponding to the electrical connection portions in the fiber optic current sensor ring; When the number of the electrolytic cell areas is N, the number of the fiber optic current sensors is (N-1); wherein: (N-1) of the fiber optic current sensors correspond to (N-1) of the electrolytic cell areas, and one fiber optic current sensor is used to enclose all the electrical connections between the anode guide rods and the horizontal busbar of the corresponding electrolytic cell area inside the sensor; the anode current of the Nth electrolytic cell area is determined based on the total current of the electrolytic cell and the current values ​​detected by the (N-1) fiber optic current sensors.

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