Connection pipe, electrolysis system, and connection method

Abstract

The present disclosure relates to a connecting pipe 50 for connecting a cell nozzle 22, which is in fluid communication with the chambers 11, 12 of an electrolytic cell 10, to an outlet header 23. The connecting pipe comprises a tube 51, an outer sleeve 52 connected to the end of the tube 51, an inner sleeve 53 disposed within the outer sleeve 52 to define an annular gap G between the outer sleeve 52 and the inner sleeve 53 for receiving the cell nozzle 22, and a seal S located between the outer sleeve 52 and the inner sleeve 53, between the end of the tube 51 and the annular gap G, the seal S being formed by a tight and inseparable connection of the outer sleeve 52 to the inner sleeve 53.

Description

[Technical Field]

[0001] The present invention relates to a connecting tube for connecting a cell nozzle in fluid communication with a chamber of an electrolytic cell to an outlet header.The present invention relates to an electrolysis system for electrolytically treating a liquid.The present invention also relates to a method for connecting a cell nozzle in fluid communication with a chamber of an electrolytic cell to an outlet header. [Background technology]

[0002] German Patent Application Publication No. 10 2017 217 361 discloses an electrolysis device for the electrolytic treatment of liquids, such as chloralkali electrolysis or alkaline water electrolysis. The electrolysis device includes an anode chamber and a cathode chamber separated from each other by an ion exchange membrane. A first liquid, such as brine in chloralkali electrolysis, is fed through an external feed pipe and nozzle into the anode chamber through an internal feed pipe. The treated liquid and gas produced at the anode are then discharged through a discharge pipe to an outlet pipe. Similarly, a second liquid, such as a dilute caustic soda solution, is dispersed across the width of the cathode chamber by a feed pipe. The treated liquid and gas produced at the cathode are then discharged through a discharge pipe to another outlet header.

[0003] An example of an existing electrolysis device is shown in Figures 5 and 6. The electrolysis device may include a number of electrolysis cells 10 arranged in parallel with one another. Each electrolysis cell 10 may comprise a housing having two half-shells, namely a cathode half-shell 11 and an anode half-shell 12. The cathode half-shell 11 and the anode half-shell 12 each have a flange-like frame 19 at their periphery, between which a membrane 13 is fastened by a seal. The membrane 13 may form a partition between the cathode half-shell 11 comprising the cathode or catholyte chamber and the anode half-shell 12 comprising the anode or anolyte chamber. The cathode half-shell 11 and the anode half-shell 12 may be connected to each other at their periphery in the region of the flange-like frame 19 via a thread 14 which may be oriented laterally, to form a closed electrolysis cell 10.

[0004] In the lower region, each of the two half-shells 11, 12 has an inlet distribution pipe 15, 16 for supplying electrolyte liquid and a tank nozzle 22, 22 through which spent electrolyte can be discharged. Baffle plates 18 may be provided within the half-shells 11, 12 to guide the flow of electrolyte during operation of the tank 10. Spent electrolyte from each of the half-shells 11, 12 may be collected in a respective outlet header 23 via an outlet hose 24 connected to the respective tank nozzle 22.

[0005] Figure 7 shows an example of an existing design of a discharge system for an electrolytic cell. In this figure, a chlorine collector outlet channel 20 for collecting residual brine and chlorine, and a hydrogen collector outlet channel 21 for collecting concentrated caustic soda and hydrogen can be seen at the top of the cell 10. A cell nozzle 22 is introduced into the cell nozzle 22 from below and is connected to the outlet channel 20 via a discharge pipe 17 that extends through the anode chamber to the outlet channel 20. The discharge pipe 17 is disposed within the cell 10 to discharge liquid and product gas from the outlet channel 20 through the cell nozzle 22 to an outlet header 23.

[0006] The discharge pipe 17 and vessel nozzle 22 are then connected to the outlet hose 24 via a flange connection 25. Flange connections 25 are used on both the vessel side and the header side. An example of a discharge pipe 17 is shown in Figure 8. It can be seen that the discharge pipe 17, with flange 17a, is inserted into the vessel nozzle 22. An example of an outlet hose 24, with flanges 24a and 24b at both ends, is shown in Figure 9. In prior art designs, the outlet hose 24 and discharge pipe 17 are installed as separate components and connected via flange connection 25.

[0007] While this flange connection 25 provides a reliable connection between the tank nozzle 22 and discharge pipe 17 and the outlet hose 24, it also increases manufacturing and assembly costs. The bolts and nuts must be tightened uniformly along the periphery with the flanges 17a and 24a in between, otherwise a sufficient seal cannot be achieved. This requires experience and time. Furthermore, the close placement of adjacent hoses makes it difficult to operate the bolts and nuts, further lengthening the assembly time. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] DE 10 2017 217 361 A1 Summary of the Invention [Problem to be solved by the invention]

[0009] An object of the present invention is to overcome the disadvantages of the prior art, and in particular to provide an arrangement and method for connecting a tank nozzle to an outlet header that is easy to assemble while maintaining a tight seal between the two. [Means for solving the problem]

[0010] The above object is solved by the subject matter of the independent claims 1, 13 and 15.

[0011] According to one aspect of the present invention, there is provided a connecting tube for connecting a cell nozzle in fluid communication with a chamber of an electrolytic cell to an outlet header, the connecting tube comprising a tube body, an outer sleeve connected to an end of the tube, an inner sleeve disposed within the outer sleeve to define an annular gap between the outer sleeve and the inner sleeve for receiving the cell nozzle, and a seal between the outer sleeve and the inner sleeve, the seal being formed by a tight, inseparable connection of the outer sleeve to the inner sleeve.

[0012] The connecting pipe can be seen as a combined (discharge) pipe-hose arrangement. With this arrangement, the flange connection described above is unnecessary. The solution of the present invention provides a single end piece that functions both as discharge pipe and outlet hose. A seal provided on the tube side of the annular gap between the outer sleeve and the inner sleeve ensures proper sealing. The outer sleeve may be pressed over the cell nozzle so that the cell nozzle is inserted into the annular gap between the outer sleeve and the inner sleeve. The end of the annular gap simultaneously provides an abutment surface for the cell nozzle, ensuring proper positioning of the end of the inner sleeve in the electrolytic cell.

[0013] The connection between the connecting pipe and the vessel nozzle may be mechanically secured by fastening means. However, since the gas-tightness is already ensured primarily by the seal between the inner sleeve and the outer sleeve, the fastening force can be reduced compared to conventional flange connections. In particular, a single threaded portion can provide sufficient fastening force without incurring excessive assembly costs. The tight, inseparable connection between the outer sleeve and the inner sleeve may preferably be a material-to-material connection between the materials of the inner sleeve and the outer sleeve.

[0014] The outer sleeve is preferably made of a flexible plastic material that can be deformed to fit onto the vessel nozzle, thereby ensuring a tight seal on the outer surface of the vessel nozzle without the need for additional fastening means, thereby ensuring a good connection between the connecting pipe and the vessel nozzle.

[0015] It is particularly preferred that the outer sleeve is made of polytetrafluoroethylene (PTFE), a material that is resistant to the harsh chemical conditions in chlor-alkali and water electrolysis and that exhibits good plastic welding properties for the outer sleeve to be welded to the inner sleeve by thermal bonding.

[0016] The seal is preferably formed by portions of the outer and inner sleeves joined by a plastic welded connection. This type of connection provides a reliable seal between the outer and inner sleeves at a relatively low cost. Alternatively or additionally, it may be conceivable to join the outer and inner sleeves, for example by adhesive bonding.

[0017] The diameter of the first portion of the outer sleeve that defines the annular gap is preferably larger than the diameter of the second portion of the outer sleeve that is fixed to the inner sleeve, thereby allowing the diameter of the inner sleeve to be constant while still defining the annular gap, thereby further reducing the cost of the connecting pipe.

[0018] The outer sleeve preferably has a tapered transition between the first and second sections to facilitate attachment of the outer sleeve to the vessel nozzle and to relieve stress at the transition when fastening forces are applied to the outer sleeve using the fastening means.

[0019] The inner sleeve preferably projects beyond the outer sleeve away from the tube, so that the inner sleeve can be inserted to a sufficient depth within the electrolytic cell.

[0020] The inner sleeve is preferably made of a plastic material, in particular PTFE. This allows for a particularly good thermoplastic welded connection between the inner and outer sleeves. It is particularly preferred if the inner and outer sleeves are made of the same plastic material. However, it is also conceivable to form the inner sleeve from, for example, metal or fiber-reinforced plastic.

[0021] The pipe body is preferably a flexible pipe, which allows for greater freedom in the arrangement of the connecting pipes. The pipe body may be a corrugated hose.

[0022] The outer sleeve and tube are preferably integrally formed, such a single piece being inexpensive to manufacture without causing fluid leakage problems.

[0023] The present invention also relates to an electrolysis system for electrolytically treating a liquid. The system comprises an electrolysis device having an anode chamber, a cathode chamber, and an ion exchange membrane separating the anode chamber from the cathode chamber, each chamber being assigned a tank nozzle. The system further comprises one or more headers. The system further comprises the above-mentioned connecting pipes. Two or more connecting pipes may be provided for each tank nozzle. The connecting pipe connects one of the tank nozzles to one of the headers, with the tank nozzle inserted into an annular gap defined between an outer sleeve and an inner sleeve of the connecting pipe. A fastening force is applied to the outer sleeve by a fastening means to fasten the outer sleeve to the tank nozzle.

[0024] Preferably, the fastening means comprises a screw clamp, comprising a strap and a threaded portion configured to tighten the strap. Such clamps are widely available on the market at low cost. Other clamps, such as spring clamps and wire clamps, are also available.

[0025] The present invention is also directed to a method for connecting a cell nozzle, which is in communication with a chamber of an electrolyzer, to a header, the method comprising providing the connecting pipe as described above, inserting the cell nozzle into an annular gap defined between an outer sleeve and an inner sleeve of the connecting pipe, and applying a fastening force to the outer sleeve using fastening means.

[0026] Various additional inventive aspects are set forth in the following description. These inventive aspects may relate to individual features and combinations of features. It is to be understood that the following detailed description is illustrative and exemplary and is not intended to limit the broad inventive concepts within the scope of the appended claims. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a perspective view of a connecting pipe according to a first embodiment of the present invention, which is attached to a bath nozzle of an electrolytic bath. [Figure 2]2 is a partially enlarged cross-sectional view of the connecting pipe of FIG. 1 attached to the tank nozzle. [Figure 3] FIG. 2 is a perspective view of the chamber of the electrolytic cell connected to the connecting pipe of FIG. 1. [Figure 4] FIG. 10 is a perspective view of a chamber of an electrolytic cell connected to a connecting pipe according to a second embodiment of the present invention. [Figure 5] FIG. 2 is a perspective view showing a cross section of an electrolytic cell. [Figure 6] FIG. 6 is a front view showing the electrolytic cell of FIG. 5. [Figure 7] 1 is a cross-sectional view of an electrolytic cell having a discharge system according to the prior art; [Figure 8] FIG. 1 is a perspective view showing a discharge pipe according to the prior art. [Figure 9] FIG. 1 is a perspective view showing an outlet hose according to the prior art. DETAILED DESCRIPTION OF THE INVENTION

[0028] FIG. 1 shows a connecting pipe according to an embodiment of the present invention, which is assembled with a cell nozzle of an electrolytic cell. The concept of the present invention is applicable to all kinds of electrolytic cells and systems for performing electrolysis using a liquid electrolyte and a product gas. An example of an electrolytic cell is shown in FIGS. 5 to 7. In the present invention, the connecting pipe 50 shown in FIG. 1 is used instead of the outlet hose 24 and the discharge pipe 17. The description of other structures of the electrolytic cell and system described above is incorporated into the description of the present invention to avoid repetition.

[0029] The connecting pipe 50 is designed to connect the vessel nozzle 22, which is in fluid communication with the chambers 11 and 12 of the vessel 10, to the outlet header 23 (see FIGS. 6 and 7) as a collection and discharge line. The connecting pipe 50 includes a pipe body 51, an outer sleeve 52, and an inner sleeve 53. An annular gap G is defined between the outer sleeve 52 and the inner sleeve 53.

[0030] The tube 51 is a portion that extends mainly between the header and the outer sleeve 52. The tube 51 may be longer than the distance between the electrolytic cell and the header (e.g., between the electrolytic cell 10 and the header 23). The tube 51 may be a flexible hose to increase the flexibility of the arrangement of the connecting tube 50. For example, the tube 51 may mainly comprise a corrugated or bellows hose. The tube 51 may be chemically resistant to the liquids and gases processed in the electrolytic cell. Most preferably, the tube 51 is made of polytetrafluoroethylene (PTFE). The tube 51 may also comprise reinforcing fibers, etc. The tube 51 may also be made of other synthetic plastic materials such as polyethylene, polyvinyl chloride, or polypropylene.

[0031] The outer sleeve 52 is connected to the end of the tube 51. The outer sleeve 52 may be made of a flexible plastic material, such as a thermoplastic resin such as polyethylene, polyvinyl chloride, or polypropylene. Most preferably, the outer sleeve 52 is made of polytetrafluoroethylene (PTFE). The plastic outer sleeve can deform to fit around the vessel nozzle 22, ensuring that the fastening force of the fastening means 54 is transmitted to the vessel nozzle 22 located in the annular gap G. This ensures a good connection between the connecting tube and the vessel nozzle.

[0032] The outer sleeve 52 may be tubular. The outer sleeve 52 may have a circular cross section. The outer sleeve 52 may have an elliptical cross section. Preferably, the outer sleeve 52 has a cross section similar to that of the inner sleeve 53, so that the width of the annular gap G is constant in the circumferential direction.

[0033] The inner sleeve 53 is positioned within the outer sleeve 52 to define an annular gap G for receiving the tank nozzle 22. The outer sleeve 52 and the inner sleeve 53 form a seal S below the annular gap G and above the tube body 51, as viewed in the longitudinal direction of the connecting tube 50. The seal S is formed by a tight and inseparable connection of the outer sleeve 52 to the inner sleeve 53. The seal S may be formed by portions 55, 57 of the outer and inner sleeves 52, 53 joined by a plastic welded connection. The welded portions 55, 57 may also be thermally bonded. For example, after inserting the inner sleeve 53 into the cavity of the outer sleeve 52, heat may be applied to the location where the seal S will be formed, thereby bonding the outer and inner sleeves 52, 53 within the portions 55, 57. Additionally or alternatively, the outer sleeve 52 and the inner sleeve 53 may be bonded to each other via one or more adhesives.

[0034] As shown in FIG. 2, the outer sleeve 52 may have a first portion P1 and a second portion P2 having a smaller diameter than the first portion P1. The outer sleeve 52 may further have a third portion P3 having a smaller diameter than the second portion P2. In the first portion P1, the outer sleeve 52 defines an annular gap G with the inner sleeve 53. The width of the annular gap G may be equal to or slightly smaller than the wall thickness of the vessel nozzle 22, thereby enabling a sealing function between the sleeves 52, 53 and the vessel nozzle 22 without the application of fastening force from the fastening means 54. The seal S is formed in the second portion P2. A tapered transition portion 56 may be provided between the first portion P1 and the second portion P2. This relieves stress at the transition portion when fastening force is applied to the outer sleeve using the fastening means 54. The third portion P3 may have the same inner diameter as the tube 51 and the inner sleeve 53. This reduces flow resistance at the end of the connecting tube 51.

[0035] The outer sleeve 52 and the tube 51 are preferably formed as a single piece, which can be manufactured inexpensively without causing problems with fluid leakage.

[0036] The inner sleeve 53 may protrude beyond the end of the outer sleeve 52 in a direction away from the tube 51. This allows the inner sleeve 53 to be inserted deep enough into the tank nozzle 22.

[0037] The inner sleeve 53 may be tubular. The inner sleeve 53 may have a circular cross-section. The inner sleeve 53 may have an elliptical cross-section. Preferably, the inner sleeve 53 has a cross-sectional shape similar to the cross-sectional shape of the tank nozzle 22.

[0038] The inner sleeve 53 may be made of a plastic material. Particularly preferably, the inner sleeve 53 may be made of polytetrafluoroethylene (PTFE). The inner sleeve 53 may be harder than the outer sleeve 52. If the inner and outer sleeves 53, 52 are made of the same material, this is because, for example, the inner sleeve 53 has a smaller diameter and / or a larger wall thickness than the outer sleeve 52. This prevents the inner sleeve 53 from being excessively deformed by the fastening force when the fastening means 54 applies a fastening force to the outer sleeve 52, thereby allowing an appropriate fastening force to be applied to the tank nozzle 22 in the annular gap G. Generally, the inner sleeve 53 may also be made of metal. The inner sleeve 53 may also be made of fiber-reinforced plastic.

[0039] The fastening means 54 is disposed around the outer sleeve 52 to apply a fastening force to the outer sleeve 52. The fastening means 54 may be configured to apply a circumferential fastening force to the outer sleeve 52. The fastening means 54 may be a screw clamp 54 and includes a strap 54a extending around the outer sleeve 52 and a threaded portion 54b configured to tighten the strap 54a.

[0040] 3, it can be seen that the connecting pipe 50 of the present invention is connected to the cell nozzle 22 of the electrolytic cell 10. To simplify the drawing, the fastening means 54 is not shown. The other or second end of the connecting pipe 50, which is connected to the outlet header, still has a flange portion 58.

[0041] FIG. 4 shows an electrolytic cell 10 connected to a connecting pipe 50 according to a second embodiment of the present invention. In contrast to the first embodiment shown in FIGS. 1 and 3, the end of the connecting pipe 50 connected to the outlet header 23 does not have a flange 58. Instead, the second end of the connecting pipe (connected to the header 23) has a structure similar to the first end (connected to the electrolytic cell 10) shown in FIG. 2. In this case, a header nozzle attached around the opening of the header is inserted into the second annular gap G' between the second outer sleeve 52' and the second inner sleeve 53', and then a second fastening means is applied around the second outer sleeve 52'. The second inner sleeve 53' preferably extends partway inside the header to prevent liquid electrolyte from being present at the mating surface between the second outer sleeve 52 and the header nozzle. Furthermore, costs during assembly and maintenance are expected to be reduced.

[0042] The present invention is also directed to an electrolysis system including the electrolysis device, the header, and the connecting pipe. The electrolysis device may be a chlor-alkali electrolysis device, an alkaline water electrolysis device, or the like.

[0043] The present invention is also directed to a method for connecting a cell nozzle communicating with a chamber of an electrolysis device to a header. The electrolysis device may be a chlor-alkali electrolysis device, an alkaline water electrolysis device, or the like. The method includes providing the connecting pipe 50 according to the present invention, inserting the cell nozzle 22 into the annular gap G defined between the outer sleeve 52 and the inner sleeve 53 of the connecting pipe 50, and applying a fastening force to the outer sleeve 52 using fastening means 54. [Explanation of symbols]

[0044] 10 Electrolytic cell 11 Half shell or chamber 12 Half shell or chamber 13 membrane 14 Threaded section 15 Inlet distribution pipe 16 Inlet distribution pipe 17 Exhaust pipe 17a Flange 18 Baffle plate 19 Edge 20,21 Outlet flow path 22 Tank nozzle 23 Exit Header 24 outlet hose 24a, 24b flange 25 Flange connection 50 Connecting pipe 51 Body 52,52' outer sleeve 53,53' inner sleeve 54 Fastening means 54a Obi section 54b Threaded part 55,57 Plastic welds 56 Tapered transition section 58 Flange G, G' annular gap S seal part P1, P2, P3 Outer sleeve parts

Claims

1. a connecting pipe (50) for connecting a cell nozzle (22) in fluid communication with the chambers (11, 12) of the electrolytic cell (10) to an outlet header (23), A tube (51); an outer sleeve (52) connected to a first end of the tube (51); an inner sleeve (53) disposed within the outer sleeve (52), thereby defining an annular gap (G) between the inner sleeve (53) and the outer sleeve (52) for receiving the vessel nozzle (22); a seal portion (S) between the outer sleeve (52) and the inner sleeve (53) and positioned between the end of the pipe body (51) and the annular gap (G); Equipped with The seal (S) is formed by a tight and inseparable connection of the outer sleeve (52) to the inner sleeve (53). Connecting tube (50).

2. 2. The connecting pipe (50) of claim 1, wherein the outer sleeve (52) is made of a flexible plastic material.

3. The connector (50) of claim 2, wherein the outer sleeve (52) is made of polytetrafluoroethylene (PTFE).

4. The connecting pipe (50) according to any one of claims 1 to 3, wherein the seal (S) is formed by portions (55, 57) of the outer and inner sleeves (52, 53) joined by a plastic welded connection.

5. The connecting pipe (50) according to any one of claims 1 to 4, wherein a diameter of a first portion (P1) of the outer sleeve (52) defining the annular gap (G) is larger than a diameter of a second portion (P2) of the outer sleeve (52) fixed to the inner sleeve (53).

6. 6. The connecting pipe (50) of claim 5, wherein the outer sleeve (52) has a tapered transition (56) between the first portion (P1) and the second portion (P2).

7. The connecting pipe (50) according to any one of claims 1 to 6, wherein the inner sleeve (53) projects from the outer sleeve (52) in a direction away from the pipe body (51).

8. The connecting pipe (50) according to any one of claims 1 to 7, wherein the inner sleeve (53) is made of a plastic material.

9. 9. The connecting pipe (50) according to claim 8, wherein the inner sleeve (53) is made of polytetrafluoroethylene (PTFE).

10. The connecting pipe (50) according to any one of claims 1 to 9, wherein the pipe body (51) is a flexible pipe.

11. The connecting pipe (50) according to any one of claims 1 to 10, wherein the pipe (51) is a corrugated hose.

12. The connecting pipe (50) according to any one of claims 1 to 11, wherein the outer sleeve (52) and the tube body (51) are integrally formed.

13. 1. An electrolysis system for electrolytically treating a liquid, comprising: an electrolytic cell (10) having an anode chamber (12), a cathode chamber (11) and an ion exchange membrane (13) separating the anode chamber (12) from the cathode chamber (11), each of the chambers (11, 12) being assigned a cell nozzle (22); one or more headers (23); a connecting pipe (50) according to any one of claims 1 to 12, which connects one of the tank nozzles (22) to one of the headers (23) with the tank nozzle (22) inserted in the annular gap (G) defined between the outer sleeve (52) and the inner sleeve (53) of the connecting pipe (50); Equipped with A fastening force is applied to the outer sleeve (52) by fastening means (54) to fasten the outer sleeve (52) to the tank nozzle (22). Electrolysis system.

14. 14. The electrolysis system of claim 13, wherein the fastening means (54) comprises a screw clamp, comprising a strap (54a) extending around the outer sleeve (52) and a threaded portion (54b) configured to tighten the strap (54a).

15. 1. A method for connecting a cell nozzle (22) communicating with a chamber (11, 12) of an electrolysis device (10) to a header, comprising the steps of: Providing a connecting pipe (50) according to any one of claims 1 to 12; inserting the tank nozzle (22) into the annular gap (G) defined between the outer sleeve (52) and the inner sleeve (53) of the connecting pipe (50); applying a fastening force to the outer sleeve (52) using fastening means (54); A method comprising:

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