Ion exchange membrane electrolyzer

Abstract

The utility model relates to an ion exchange membrane electrolytic cell belongs to electrolytic cell technical field, including at least two parallel interval arrangement's electrolytic cell frame, and the electrolytic cell unit is equipped in the frame, and the electrolytic cell unit is equipped with anode chamber and cathode chamber, and is equipped with ion exchange membrane between anode chamber and cathode chamber, and is equipped with anode assembly and multiple elastic pressure contact piece in anode chamber, and anode assembly is pasted with ion exchange membrane through elastic pressure contact piece, and is equipped with cathode assembly in cathode chamber, and cathode assembly is pasted with ion exchange membrane, and the bottom of anode chamber is equipped with anode liquid inlet and liquid inlet distributor, and liquid inlet distributor communicates with anode liquid inlet, and its top is equipped with anode exhaust port, and the bottom of cathode chamber is equipped with cathode liquid inlet, and its top is equipped with cathode exhaust port, and the cathode flow guide plate is obliquely arranged in cathode chamber. The compression amount of multiple elastic pressure contact pieces is used to keep the interelectrode distance between anode assembly and cathode assembly long-term stable, avoid ohmic voltage drop with time to increase, thereby reduce the energy consumption of electrolytic cell.

Description

Technical Field

[0001] This utility model relates to the field of electrolytic cell technology, and more specifically to an ion membrane electrolytic cell. Background Technology

[0002] The ion-exchange membrane electrolyzer is the core equipment for caustic soda production. Its core principle is to introduce refined brine into the anode chamber and pure water into the cathode chamber. After energizing, sodium ions are directionally migrated using an ion-selective exchange membrane, and finally caustic soda is generated in the cathode chamber.

[0003] Currently, the single-cell voltage of an ion-exchange membrane electrolyzer is the core indicator determining electrolysis energy consumption. Most existing ion-exchange membrane electrolyzers use a rigid gasket support and integral bolt clamping structure to control the anode-cathode spacing. However, this rigid structure lacks elastic deformation capability. During operation, the rigid gasket and integral bolts may be affected by temperature deformation, pressure fluctuations, and material aging, resulting in uneven anode-cathode spacing. This leads to an excessively high ohmic voltage drop, and the electrolyzer's energy consumption gradually increases with operating time. Furthermore, the anode and cathode chambers of these electrolyzers often use a single bottom-feed tube without corresponding flow guiding or diversion structures. This results in uneven liquid distribution, large ion concentration gradients within the chambers, and concentration overpotential issues, leading to higher electrolyzer voltage values ​​and further increasing energy consumption. Utility Model Content

[0004] In view of the shortcomings of the existing technology, the present invention provides an ion membrane electrolyzer to address the technical problem of high energy consumption in existing electrolyzers.

[0005] To achieve the above objectives, this utility model adopts the following technical solution:

[0006] This utility model provides an ion membrane electrolyzer, comprising: at least two electrolyzer frames arranged side by side and spaced apart on a tank frame, wherein an electrolyzer unit is provided within the electrolyzer frame, and a first exhaust port and a second exhaust port are respectively provided at both ends of the electrolyzer frame.

[0007] The electrolytic cell unit has an anode chamber on one side and a cathode chamber on the other side, with an ion exchange membrane between the anode chamber and the cathode chamber.

[0008] The anode chamber is provided with an anode assembly and multiple elastic pressing components, and the anode assembly is attached to the ion exchange membrane through the elastic pressing components; the cathode chamber is provided with a cathode assembly, and the cathode assembly is attached to the ion exchange membrane;

[0009] The bottom of the anode chamber is provided with an anode inlet and an inlet distributor, one end of which is connected to the anode inlet; the top of the anode chamber is provided with an anode exhaust port, which is connected to the first exhaust port.

[0010] The cathode chamber has a cathode inlet at the bottom and a cathode exhaust port at the top, and the cathode exhaust port is connected to the second exhaust port; a cathode guide plate is inclinedly arranged inside the cathode chamber.

[0011] Preferably, the anode assembly includes an anode support mesh and an anode coating; the porosity of the anode support mesh near the anode inlet is lower than that at the other end.

[0012] Preferably, the cathode assembly includes a cathode support mesh and a cathode coating; the aperture ratio of the cathode support mesh near the cathode inlet is lower than that at the other end.

[0013] Preferably, the liquid inlet distributor is a porous titanium tube, and the surface of the porous titanium tube is provided with multiple guide fins.

[0014] Preferably, the elastic pressing element is one of a nickel alloy spring and a nickel alloy spring sheet.

[0015] Preferably, the outer side of the shell of the anode chamber is provided with an anode heat exchange jacket for heat exchange in the anode chamber; the outer side of the shell of the cathode chamber is provided with a cathode heat exchange jacket for heat exchange in the cathode chamber; heat exchange pipes are evenly distributed inside the anode heat exchange jacket and the cathode heat exchange jacket.

[0016] Preferably, the anode chamber is provided with an anode gas-liquid filter screen inside, and a first drain pipe is provided on the side wall of the anode chamber; the cathode chamber is provided with a cathode gas-liquid filter screen inside, and a second drain pipe is provided on the side wall of the cathode chamber.

[0017] Preferably, a first gas-liquid separator is provided at the top of the anode chamber, and the inlet of the first gas-liquid separator is connected to the anode exhaust port; a second gas-liquid separator is provided at the top of the cathode chamber, and the inlet of the second gas-liquid separator is connected to the cathode exhaust port.

[0018] In summary, this utility model has the following beneficial effects:

[0019] The ion-exchange membrane electrolyzer provided by this invention utilizes multiple elastic compression members between the anode assembly and the ion exchange membrane. The anode assembly is bonded to the ion exchange membrane via these members, while the reaction force of the elastic compression members ensures a tight bond between the cathode assembly and the ion exchange membrane. The compression of these members maintains a stable inter-electrode distance between the anode and cathode assemblies over a long period, preventing the ohmic voltage drop from increasing over time and thus reducing the electrolyzer's energy consumption. Furthermore, a liquid distributor is installed in the anode chamber, and a cathode guide plate is installed in the cathode chamber. These components ensure uniform diffusion of the input liquid within the anode and cathode chambers, reducing concentration overpotential and further lowering the electrolyzer's energy consumption. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the ion-exchange membrane electrolyzer structure of this utility model;

[0021] Figure 2 This is a perspective view of the electrolytic cell unit of this utility model;

[0022] Figure 3 This is a three-dimensional structural diagram of the electrolytic cell unit of this utility model;

[0023] Figure 4 This is a schematic diagram of the anode assembly structure of this utility model;

[0024] Figure 5 This is a schematic diagram of the cathode assembly structure of this utility model;

[0025] Figure 6 This is a schematic diagram of the liquid inlet distributor of this utility model;

[0026] Figure 7 This is a schematic diagram of the electrolytic cell unit structure with heat exchange jacket of this utility model;

[0027] Figure 8 This is a perspective view of an electrolytic cell unit according to another embodiment of the present invention;

[0028] Reference numerals: 1. Electrolytic cell frame; 101. First exhaust port; 102. Second exhaust port; 2. Ion exchange membrane; 3. Anode assembly; 301. Anode support mesh; 302. Anode coating; 4. Elastic crimping component; 5. Cathode assembly; 501. Cathode support mesh; 502. Cathode coating; 6. Anode inlet; 7. Anode exhaust port; 8. Inlet distributor; 801. Porous titanium tube; 802. Guide fins; 9. Cathode inlet; 10. Cathode exhaust port; 11. Cathode guide plate; 12. Anode heat exchange jacket; 13. Cathode heat exchange jacket; 14. Anode gas-liquid filter screen; 15. First drain pipe; 16. Cathode gas-liquid filter screen; 17. Second drain pipe; 18. Desalinated water main pipe; 19. Pure water main pipe; 20. Chlorine main pipe; 21. Hydrogen main pipe. Detailed Implementation

[0029] The present invention will be further described in detail below with reference to the accompanying drawings.

[0030] To make the objectives, solutions, and advantages of this utility model clearer, the following detailed description of this utility model is provided in conjunction with the embodiments and accompanying drawings. The illustrative embodiments and descriptions of this utility model are only used to explain this utility model and are not intended to limit this utility model.

[0031] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to implement the present invention. In other embodiments, well-known structures, circuits, materials, or methods are not specifically described in order to avoid obscuring the present invention.

[0032] In the description of this utility model, the terms "front", "rear", "left", "right", "up", "down", "vertical", "horizontal", "high", "low", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this utility model.

[0033] The following is in conjunction with the appendix of this utility model. Figures 1-8 The embodiments of this utility model will be described in detail below.

[0034] Reference Figure 1 , Figure 2 and Figure 3 As shown, the ion membrane electrolyzer provided in this embodiment includes at least two electrolyzer frames 1 arranged side by side and spaced apart on the tank frame. An electrolyzer unit is provided in the electrolyzer frame 1, and a first exhaust port 101 and a second exhaust port 102 are respectively provided at both ends of the electrolyzer frame 1.

[0035] Figure 1 In this design, the electrolytic cell frame 1 adopts a modular design, allowing multiple electrolytic cell frames 1 to be assembled on a cell rack. The brine main pipe 18, pure water main pipe 19, chlorine main pipe 20, and hydrogen main pipe 21 are connected to the inlet and outlet of each electrolysis unit module in the electrolytic cell frame 1 via quick-connect couplings, achieving centralized liquid supply and centralized exhaust and drainage. Then, the gas-liquid mixture in the chlorine main pipe 20 and hydrogen main pipe 21 is separated into gas and liquid streams using appropriate gas-liquid separation equipment.

[0036] like Figure 2 As shown, the electrolytic cell unit has an anode chamber on one side and a cathode chamber on the other side, with an ion exchange membrane 2 between the anode chamber and the cathode chamber.

[0037] The anode chamber is equipped with an anode assembly 3 and multiple elastic pressing parts 4. The anode assembly 3 is bonded to the ion exchange membrane 2 through the elastic pressing parts 4. The cathode chamber is equipped with a cathode assembly 5, which is bonded to the ion exchange membrane 2.

[0038] The bottom of the anode chamber is provided with an anode inlet 6 and an inlet distributor 8, one end of which is connected to the anode inlet 6; the top of the anode chamber is provided with an anode exhaust port 7, which is connected to the first exhaust port 101.

[0039] The cathode chamber has a cathode inlet 9 at the bottom and a cathode exhaust port 10 at the top, which is connected to the second exhaust port 102; a cathode guide plate 11 is inclinedly arranged inside the cathode chamber.

[0040] The cathode guide plate 11 is a corrugated nickel plate with a wave height of 5-8 mm and a wave pitch of 20-30 mm. Specifically, it can be fixed to the shell inside the cathode chamber with bolts. The cathode guide plate 11 is set at an angle. The corrugated groove of the cathode guide plate 11 causes the pure water to generate lateral disturbance during the rising process, reducing the adhesion of bubbles on the cathode assembly 5 and further promoting gas-liquid separation.

[0041] In this embodiment, the ion-exchange membrane electrolyzer uses multiple elastic compression members 4 between the anode assembly 3 and the ion exchange membrane 2. The anode assembly 3 is bonded to the ion exchange membrane 2 through these elastic compression members 4. Simultaneously, the reaction force of the elastic compression members 4 ensures a tight bond between the cathode assembly 5 and the ion exchange membrane 2. The compression of the multiple elastic compression members 4 maintains a stable electrode spacing between the anode assembly 3 and the cathode assembly 5 over a long period, preventing the ohmic voltage drop from increasing over time and thus reducing the energy consumption of the electrolyzer. Furthermore, a liquid distributor 8 is installed in the anode chamber, and a cathode guide plate 11 is installed in the cathode chamber. The liquid distributor 8 and the cathode guide plate 11 ensure uniform diffusion of the input liquid in the anode and cathode chambers, respectively, reducing the concentration overpotential within the chambers and further reducing the energy consumption of the electrolyzer.

[0042] like Figure 4 As shown, the anode assembly 3 in this embodiment includes an anode support mesh 301 and an anode coating 302; the porosity of the anode support mesh 301 near the anode inlet 6 is lower than that of the other end.

[0043] Among them, the anode support mesh 301 is a titanium-based support mesh, the anode coating 302 is a ruthenium-iridium oxide coating, and the anode assembly 3 is bonded to the ion exchange membrane 2 through the elastic pressing member 4 to achieve zero electrode spacing optimization, that is, the electrode spacing between the anode assembly 3 and the cathode assembly 5 = the thickness of the ion exchange membrane 2 + the compression amount of the elastic pressing member 4.

[0044] Meanwhile, in order to reduce the concentration difference overpotential, the anode support mesh 301 in this embodiment adopts a gradient opening design. The electrode opening ratio in the area near the anode inlet 6 is slightly lower to avoid ion scouring and loss caused by excessive local flow rate, while the opening ratio in the area away from the anode inlet 6 is slightly higher to promote electrolyte circulation and replenish ions.

[0045] like Figure 5 As shown, the cathode assembly 5 in this embodiment includes a cathode support mesh 501 and a cathode coating 502; the opening ratio of the cathode support mesh 501 near the cathode inlet 9 is lower than that of the other end.

[0046] Specifically, the cathode support mesh 501 is a nickel-based porous mesh, the cathode coating 502 is a platinum coating, and the cathode assembly 5 and the ion exchange membrane 2 are tightly bonded together by the reaction force of the elastic pressing member 4 to form a zero-gap structure. Similar to the anode assembly 3, the cathode support mesh 501 in this embodiment also adopts a gradient opening design, that is, the opening ratio at the end near the cathode inlet 9 is lower than the opening ratio at the other end (i.e., the end away from the cathode inlet 9), and the gradient opening reduces the concentration difference overpotential.

[0047] Reference Figure 6 As shown, the liquid distributor 8 in this embodiment is a porous titanium tube 801, and the surface of the porous titanium tube 801 is provided with multiple guide fins 802. In this embodiment, in order to improve the uniformity of concentration distribution in the anode chamber, a porous titanium tube 801 is used to distribute the brine, so that the brine input from the anode inlet 6 can be sprayed out through the holes on the porous titanium tube 801, avoiding side reactions caused by excessively low local concentrations.

[0048] Meanwhile, in order to improve the uniformity of the distribution of brine along the surface of the anode assembly 3, this embodiment also provides a flow guide fin 802 on the surface of the porous titanium tube 801 to guide the brine sprayed from the porous titanium tube 801 to the surface of the anode assembly 3, guide the brine to diffuse radially along the anode surface, avoid the liquid from concentrating in the area around the tube, and further improve the uniformity of distribution.

[0049] In this embodiment, the elastic pressing member 4 is one of a nickel alloy spring and a nickel alloy spring sheet. Preferably, the elastic pressing member 4 is a nickel alloy spring sheet, and both ends of the nickel alloy spring sheet can be fixed to the anode support mesh 301 of the anode assembly 3 by bolts. By setting multiple nickel alloy spring sheets (i.e., elastic pressing members 4) between the anode assembly 3 and the ion exchange membrane 2, when the anode assembly 3 is fixed in the housing of the anode chamber by bolts, the anode assembly 3 will compress the distance between itself and the ion exchange membrane 2. At the same time, the ion exchange membrane 2 can also be bonded to the cathode assembly 5 by the reaction force of the nickel alloy spring sheets (i.e., elastic pressing members 4).

[0050] like Figure 7 As shown, an anode heat exchange jacket 12 is provided on the outer side of the shell of the anode chamber for heat exchange in the anode chamber; a cathode heat exchange jacket 13 is provided on the outer side of the shell of the cathode chamber for heat exchange in the cathode chamber; heat exchange pipes are evenly distributed inside the anode heat exchange jacket 12 and the cathode heat exchange jacket 13.

[0051] In this embodiment, the anode heat exchange jacket 12 and the cathode heat exchange jacket 13 are specifically composed of a jacket with heat exchange pipes arranged inside. The heat exchange channels are provided with water inlets and outlets at both ends. The jacket is fixed to the electrolytic cell frame 1 by bolts. Hot water or cooling water at 80-90℃ is introduced into the heat exchange channels to achieve heat exchange between the anode chamber and the cathode chamber, thereby stabilizing the electrolysis temperature in the anode chamber and the cathode chamber within a suitable range, thereby reducing voltage loss caused by uneven temperature.

[0052] like Figure 8 As shown, in this embodiment, to achieve gas-liquid separation, an anode gas-liquid filter 14 is provided inside the anode chamber, and a first drain pipe 15 is provided on the side wall of the anode chamber; a cathode gas-liquid filter 16 is provided inside the cathode chamber, and a second drain pipe 17 is provided on the side wall of the cathode chamber. The gas-liquid mixture generated by electrolysis in the anode and cathode chambers is separated by the anode gas-liquid filter 14 and the cathode gas-liquid filter 16. At the same time, the unelectrolyzed brine and caustic soda solution in the anode and cathode chambers can be discharged through the first drain pipe 15 and the second drain pipe 17, or fed into the next electrolytic cell unit for recycling.

[0053] In another embodiment of this utility model, a first gas-liquid separator is provided at the top of the anode chamber, and the inlet of the first gas-liquid separator is connected to the anode exhaust port 7; a second gas-liquid separator is provided at the top of the cathode chamber, and the inlet of the second gas-liquid separator is connected to the cathode exhaust port 10. The first and second gas-liquid separators are used to separate the gas-liquid mixture generated by electrolysis in the anode and cathode chambers, respectively, to prevent chlorine and hydrogen from carrying liquid into the chlorine main pipe 20 and the hydrogen main pipe 21.

[0054] Specifically, the first and second gas-liquid separators can be baffle-type gas-liquid separators. The gas-liquid mixture generated by electrolysis (such as hydrogen and caustic soda solution in the cathode chamber) enters from the bottom of the separator through the anode exhaust port 7 and the cathode exhaust port 10. The flow direction is changed by the multiple layers of inclined baffles inside the baffle-type gas-liquid separator. The liquid, due to its higher density, settles to the bottom of the separator, while the gas, due to its lower density, rises to the top. The settled liquid is discharged directly through the caustic soda solution outlet at the bottom of the separator, while the hydrogen is discharged through the outlet at the top and enters the hydrogen main pipe 21, and the chlorine is discharged through the outlet at the top and enters the chlorine main pipe 20, thus achieving gas-liquid separation.

[0055] In addition, other types of gas-liquid separators can be selected according to actual production needs. The specific selection depends on the actual situation, and this embodiment does not make specific limitations here.

[0056] In this embodiment, the ion-exchange membrane electrolyzer operates as follows during caustic soda production: In the liquid inlet stage: Refined brine enters the anode inlet 6 via the brine main pipe 18 and branch pipes, and is evenly diffused into the anode chamber by the liquid distributor 8; pure water enters the cathode inlet 9 via the pure water main pipe 19 and branch pipes, and flows through the cathode chamber under the guidance of the cathode guide plate 11. In the electrolysis stage: Direct current is applied, a chlorine evolution reaction occurs in the anode chamber, and a hydrogen evolution reaction occurs in the cathode chamber. Na⁺ migrates through the ion exchange membrane 2 to the cathode chamber and combines with OH⁻ to form caustic soda; the elastic pressing member 4 continuously maintains a stable electrode spacing, and the electrolysis temperature of the anode and cathode chambers is controlled at 80℃ through the anode heat exchange jacket 12 and the cathode heat exchange jacket 13. Gas-liquid discharge stage: After passing through the anode gas-liquid filter 14 or the first gas-liquid separator, chlorine gas enters the chlorine main pipe 20 from the first exhaust port 101; after passing through the cathode gas-liquid filter 16 or the second gas-liquid separator, hydrogen gas enters the hydrogen main pipe 21 from the second exhaust port 102; caustic soda solution is discharged from the second drain pipe 17 and enters the subsequent refining process.

[0057] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. An ion-exchange membrane electrolyzer, characterized in that, include: At least two parallel electrolytic cell frames (1) are arranged at intervals on a cell rack. Each electrolytic cell frame (1) contains an electrolytic cell unit. A first exhaust port (101) and a second exhaust port (102) are respectively located at both ends of each electrolytic cell frame (1). An anode chamber is located on one side of each electrolytic cell unit, and a cathode chamber is located on the other side. An ion exchange membrane (2) is located between the anode and cathode chambers. An anode assembly (3) and multiple elastic compression fittings (4) are located within the anode chamber. The anode assembly (3) is bonded to the ion exchange membrane (2) via the elastic compression fittings (4). A cathode assembly (5) is located within the cathode chamber. The cathode assembly (5) is attached to the ion exchange membrane (2); the bottom of the anode chamber is provided with an anode inlet (6) and an inlet distributor (8), one end of the inlet distributor (8) is connected to the anode inlet (6); the top of the anode chamber is provided with an anode exhaust port (7), the anode exhaust port (7) is connected to the first exhaust port (101); the bottom of the cathode chamber is provided with a cathode inlet (9), the top is provided with a cathode exhaust port (10), the cathode exhaust port (10) is connected to the second exhaust port (102); a cathode guide plate (11) is inclinedly arranged inside the cathode chamber.

2. The ion-exchange membrane electrolyzer according to claim 1, characterized in that: The anode assembly (3) includes an anode support mesh (301) and an anode coating (302); the anode support mesh (301) has a lower porosity at one end near the anode inlet (6) than at the other end.

3. The ion-exchange membrane electrolyzer according to claim 1, characterized in that: The cathode assembly (5) includes a cathode support mesh (501) and a cathode coating (502); the aperture ratio of the cathode support mesh (501) near the cathode inlet (9) is lower than that of the other end.

4. The ion-exchange membrane electrolyzer according to claim 1, characterized in that: The liquid inlet distributor (8) is a porous titanium tube (801), and the surface of the porous titanium tube (801) is provided with multiple guide fins (802).

5. The ion-exchange membrane electrolyzer according to claim 1, characterized in that: The elastic pressing component (4) is one of a nickel alloy spring and a nickel alloy spring sheet.

6. The ion-exchange membrane electrolyzer according to claim 1, characterized in that: The outer side of the shell of the anode chamber is provided with an anode heat exchange jacket (12) for heat exchange of the anode chamber; the outer side of the shell of the cathode chamber is provided with a cathode heat exchange jacket (13) for heat exchange of the cathode chamber; heat exchange pipes are evenly distributed inside the anode heat exchange jacket (12) and the cathode heat exchange jacket (13).

7. The ion-exchange membrane electrolyzer according to claim 1, characterized in that: The anode chamber is provided with an anode gas-liquid filter screen (14) and a first drain pipe (15) is provided on the side wall of the anode chamber; the cathode chamber is provided with a cathode gas-liquid filter screen (16) and a second drain pipe (17) is provided on the side wall of the cathode chamber.

8. The ion-exchange membrane electrolyzer according to claim 1, characterized in that: The top of the anode chamber is provided with a first gas-liquid separator, the inlet of which is connected to the anode exhaust port (7); the top of the cathode chamber is provided with a second gas-liquid separator, the inlet of which is connected to the cathode exhaust port (10).

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