Electrolytic tank unit

Abstract

To provide an electrolytic tank unit capable of decreasing the difference of concentration in a raw material liquid present in an electrode chamber and suppressing deterioration in the electrolytic efficiency.SOLUTION: The electrolytic tank unit comprises an electrode chamber in which an electrode is installed, a gas / liquid separation chamber disposed above the electrode chamber, a feed nozzle for feeding an electrolytic liquid into the electrode chamber, electrolytic liquid recovery means for recovering the electrolytic liquid present in the gas / liquid separation chamber to return the electrolytic liquid to the feed nozzle, and a dispersion conduit connected to the feed nozzle and the electrolytic liquid recovery means. The dispersion conduit comprises a discharge opening for dispersing / discharging a liquid mixture of the electrolytic liquid fed from the feed nozzle and the electrolytic liquid recovered by the electrolytic liquid recovery means, into the electrode chamber.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an electrolytic cell unit that can be applied to either the electrolysis of an aqueous solution of an alkali metal chloride, such as sodium chloride, or the electrolysis of an aqueous solution of an alkali metal hydroxide, such as potassium hydroxide. [Background technology]

[0002] The electrolytic cell unit is a component of a bipolar electrolytic cell for electrolyzing an aqueous solution of an alkali metal chloride, such as sodium chloride, or an aqueous solution of an alkali metal hydroxide, such as potassium hydroxide.

[0003] The electrolytic cell unit includes an electrode chamber and a gas-liquid separation chamber disposed above the electrode chamber. A supply nozzle is attached to the electrode chamber and an electrode is installed inside the electrode chamber. A discharge nozzle is attached to the gas-liquid separation chamber.

[0004] When electrolysis is performed in the electrolytic cell unit, the raw material solution is supplied from the supply nozzle into the electrode chamber, and then a voltage is applied to the electrodes. Then, the raw material solution is electrolyzed in the electrode chamber, and an electrolytic solution containing a large number of gas bubbles is generated. The electrolytic solution containing a large number of gas bubbles is sent from the electrode chamber to a gas-liquid separation chamber, where it is separated into gas and liquid, and then discharged from a discharge nozzle (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 8-100286 Summary of the Invention [Problem to be solved by the invention]

[0006] If the flow of the raw material liquid in the electrode chamber is nonuniform or if the raw material liquid stagnates, a concentration difference occurs in the raw material liquid in the electrode chamber. If the concentration difference in the raw material liquid in the electrode chamber is large, the current distribution becomes nonuniform, resulting in a problem of reduced electrolysis efficiency.

[0007] An object of the present invention is to provide an electrolytic cell unit capable of reducing the concentration difference of the raw material solution in the electrode chamber and suppressing a decrease in the efficiency of electrolysis. [Means for solving the problem]

[0008] According to the present invention, there is provided an electrolytic cell unit that solves the above problems. "An electrode chamber in which electrodes are installed, a gas-liquid separation chamber disposed above the electrode chamber; a supply nozzle for supplying a raw material liquid into the electrode chamber; a dispersion pipe connected to the supply nozzle; The dispersion pipeline has a discharge opening for dispersing and discharging the raw material liquid supplied from the supply nozzle into the electrode chamber.

[0009] Preferably, the supply nozzle extends from a lower part of a side surface of the electrode chamber outward in the width direction of the electrolytic cell unit.

[0010] It is desirable that the dispersion pipe extends in the width direction of the electrolytic cell unit, and that the discharge opening also extends in the width direction of the electrolytic cell unit. The dispersion pipe extends in the width direction of the electrolytic cell unit, and a plurality of the discharge openings may be formed at intervals in the width direction of the electrolytic cell unit.

[0011] It is preferable that the discharge opening faces the electrode, and the raw material liquid is discharged from the discharge opening toward the electrode. The discharge opening may be formed in a lower portion of the dispersion pipe.

[0012] The electrode chamber includes a partition wall installed at a distance from the electrode in the depth direction of the electrolytic cell unit, and it is convenient that gaps through which the raw material liquid discharged from the discharge opening can pass are provided between the dispersion pipe and the electrode, between the dispersion pipe and the partition wall, and between the dispersion pipe and the bottom plate of the electrode chamber.

[0013] It is desirable that a liquid drain hole is provided at the connection between the supply nozzle and the dispersion pipe, and when the raw material liquid is discharged from the electrode chamber and the gas-liquid separation chamber through the supply nozzle, the raw material liquid present between the dispersion pipe and the bottom plate of the electrode chamber is sent to the supply nozzle through the liquid drain hole.

[0014] Furthermore, it is preferable that an electrolyte recovery means is provided for recovering the electrolyte in the gas-liquid separation chamber and returning it to the supply nozzle, and a mixture of the raw material liquid supplied from the supply nozzle and the electrolyte recovered by the electrolyte recovery means is discharged from the discharge opening of the dispersion pipe into the electrode chamber.

[0015] The electrode chamber includes an anode chamber in which an anode is installed and a cathode chamber in which a cathode is installed, the gas-liquid separation chamber has an anode-side gas-liquid separation chamber disposed above the anode chamber and a cathode-side gas-liquid separation chamber disposed above the cathode chamber, the supply nozzle includes a first supply nozzle for supplying a raw material liquid into the inside of the anode chamber and a second supply nozzle for supplying a raw material liquid into the inside of the cathode chamber, the electrolytic solution recovery means includes a first electrolytic solution recovery means that recovers the electrolytic solution in the anode side gas-liquid separation chamber and returns it to the first supply nozzle, and a second electrolytic solution recovery means that recovers the electrolytic solution in the cathode side gas-liquid separation chamber and returns it to the second supply nozzle, The dispersion conduit is preferably connected to the first supply nozzle.

[0016] It is preferable that a recovery hole is formed in a partition plate which separates the electrode chamber from the gas-liquid separation chamber, and the electrolyte recovery means recovers the electrolyte flowing out from the recovery hole and returns it to the supply nozzle.

[0017] The electrolyte recovery means preferably has a horizontal pipeline for sending the electrolyte recovered from the gas-liquid separation chamber to one end in the width direction, and a vertical pipeline for returning the electrolyte sent to the one end in the width direction to the supply nozzle. Effect of the Invention

[0018] In the electrolytic cell unit of the present invention, the raw material liquid supplied from the supply nozzle is dispersed and discharged into the electrode chamber, which promotes uniformity of the concentration distribution of the raw material liquid in the electrode chamber, thereby suppressing a decrease in electrolysis efficiency. [Brief description of the drawings]

[0019] [Figure 1] FIG. 2 is a front view of the electrolytic cell unit according to the present invention. [Diagram 2] Cross-sectional view taken along line II-II in Figure 1. [Diagram 3] 3 is a cross-sectional view (corresponding to the cross-section of FIG. 2) when no clad plate is interposed. [Figure 4] Enlarged view of the top of Figure 2. [Diagram 5] Enlarged view of the bottom of Figure 2. [Figure 6] 2 is a perspective view of a first supply nozzle, a first electrolyte recovery means, and a first dispersion pipeline of the electrolytic cell unit shown in FIG. 1; [Figure 7] 2 is a perspective view of a second supply nozzle, a second electrolyte recovery means, and a second dispersion pipeline of the electrolytic cell unit shown in FIG. 1. [Figure 8] Cross-sectional view taken along line VIII-VIII in FIG. 5 . [Figure 9] Cross-sectional view taken along line IX-IX in Figure 5. [Figure 10] 9A is a perspective view of a state in which a second supply nozzle and a second electrolyte recovery means are connected in the absence of a second dispersion pipeline, and FIG. 9B is a cross-sectional view shown in FIG. 9A (corresponding to the cross-section of FIG. 9). [Figure 11]9A is a perspective view showing a state in which the second supply nozzle and the second electrolyte recovery means are not connected when there is no second dispersion pipeline, and FIG. 9B is a cross-sectional view shown in FIG. 9A (corresponding to the cross-section in FIG. 9). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, preferred embodiments of the electrolytic cell unit of the present invention will be described with reference to the drawings.

[0021] (Electrolyzer unit 2) Explaining with reference to Figures 1 and 2, the electrolytic cell unit 2 comprises an electrode chamber 4 in which electrolysis of liquid takes place, and a gas-liquid separation chamber 6 for separating gas generated by electrolysis from the electrolytic solution.

[0022] (Electrode chamber 4) 2, the electrode chamber 4 includes an anode chamber 8 made of a first material and a cathode chamber 10 made of a second material. The anode chamber 8 and the cathode chamber 10 are disposed adjacent to each other in the depth direction of the electrolytic cell unit 2 (the direction indicated by the arrow D in FIG. 2).

[0023] 1 is the width direction of electrolytic cell unit 2, and the V direction shown by arrow V in Fig. 1 is the up-down direction. The D direction, W direction, and V direction are perpendicular to each other.

[0024] Regarding the first and second materials, when the electrolytic cell unit 2 is applied to the electrolysis of an alkali metal chloride aqueous solution, the first material may be titanium (Ti) and the second material may be nickel (Ni), for example. On the other hand, when the electrolytic cell unit 2 is applied to the electrolysis of an alkali metal hydroxide aqueous solution, the first and second materials may be the same, and nickel (Ni), for example, may be employed as the first and second materials.

[0025] (Anode chamber 8) 2, the anode chamber 8 includes a first partition wall 12, an anode 14 arranged at a distance from the first partition wall 12 in direction D, and a bottom plate 16 extending in direction D from a lower end of the first partition wall 12 toward the anode 14. The anode 14 is a sheet-like member having numerous openings, such as an expanded metal or a plain woven wire mesh.

[0026] The anode chamber 8 further includes a pair of left and right side walls 18 extending in the D direction from both ends of the first partition wall 12 in the W direction toward the anode 14 (see FIG. 8). However, only one of the side walls 18 is shown in FIG. 8. The anode chamber 8 is formed into a rectangular parallelepiped shape by the first partition wall 12, the anode 14, the bottom plate 16, and the side walls 18.

[0027] 2, a flange wall 20 extending downward is connected to the tip (the end on the anode 14 side) of the bottom plate 16. An outer peripheral plate 22 extending in the D direction toward the first partition wall 12 is connected to the lower end of the flange wall 20.

[0028] Similar to the bottom plate 16, a flange wall 24 (see FIG. 1) extending outward in the W direction is connected to the tip (the end of the anode side 14) of the side wall 18. An outer peripheral plate 26 (see FIG. 8) extending in the D direction toward the first partition wall 12 is connected to the outer end of the flange wall 24 in the W direction.

[0029] (Cathode chamber 10) 2, the cathode chamber 10 includes a second partition wall 28, a current collector 30 arranged at a distance from the second partition wall 28 in direction D, and a bottom plate 32 extending in direction D from a lower end of the second partition wall 28 toward the current collector 30. The current collector 30 is a rectangular sheet-like member having many openings, such as an expanded metal or a plain woven wire mesh.

[0030] 2, a cathode 36 is attached to the outer surface of the current collector 30 via a cushioning material 34. The cushioning material 34 is an elastic mat as a whole that can be formed as an assembly of metal wires. The cathode 36 is a sheet-like member having many openings, such as an expanded metal or a plain woven wire mesh.

[0031] The cathode chamber 10 further includes a pair of left and right side walls 38 extending in the D direction from both ends of the second partition wall 28 in the W direction toward the current collector 30 (see FIG. 9). However, only one of the side walls 38 is shown in FIG. The cathode chamber 10 is formed into a rectangular parallelepiped shape by the second partition wall 28, the current collector 30, the cushion material 34, the cathode 36, the bottom plate 32, and the side walls 38.

[0032] 2, a flange wall 40 extending downward is connected to the tip (the end on the current collector 30 side) of the bottom plate 32. An outer peripheral plate 42 extending in the D direction toward the second partition wall 28 is connected to the lower end of the flange wall 40.

[0033] Similar to the bottom plate 32, a flange wall (not shown) extending outward in the W direction is connected to the tip (the end on the current collector 30 side) of the side wall 38. An outer peripheral plate 44 (see FIG. 9 ) protruding in the D direction toward the second partition wall 28 side is connected to the outer end of the flange wall in the W direction.

[0034] (Clad plate 46) 2, the anode chamber 8 and the cathode chamber 10 are connected via a clad plate 46. The clad plate 46 in this embodiment is a plate material with a two-layer structure in which a layer 46a of a first material and a carbon steel 46b are bonded by explosive bonding.

[0035] The clad plate 46 is positioned between the first partition wall 12 and the second partition wall 28. A plurality of clad plates 46 are installed at intervals in the W direction. A layer 46a of a first material of the clad plate 46 is joined to the first partition wall 12 made of the first material, and a carbon steel 46b of the clad plate 46 is joined to the second partition wall 28 made of the second material.

[0036] As described above, when the electrolytic cell unit 2 is applied to the electrolysis of an aqueous alkali metal hydroxide solution, the first and second materials may be the same. When the first and second materials are the same, the clad plate 46 is not necessary. When the clad plate 46 is not interposed, the anode chamber 8 and the cathode chamber 10 are directly connected. Specifically, the first partition wall 12 and the second partition wall 28 can be directly joined.

[0037] Alternatively, when no clad plate 46 is interposed, the second partition wall 28 may not be provided. That is, as shown in Fig. 3, the anode chamber 8 and the cathode chamber 10 may be separated by the first partition wall 12. In this case, the first partition wall 12 is connected to the bottom plate 32 and a pair of side walls 38 of the cathode chamber 10.

[0038] Although not shown, when no clad plate 46 is interposed, the first partition wall 12 may not be provided, and the anode chamber 8 and the cathode chamber 10 may be separated by the second partition wall 28, as opposed to the configuration shown in Fig. 3. In this case, the second partition wall 28 is connected to the bottom plate 16 and a pair of side walls 18 of the anode chamber 8.

[0039] In the following, a case where a clad plate 46 is interposed will be described, but in a configuration in which the clad plate 46 and the second partition wall 28 are not provided (for example, the configuration shown in FIG. 3), the second partition wall 28 should be read as the first partition wall 12. In addition, in a configuration in which the clad plate 46 and the first partition wall 12 are not provided (not shown), the first partition wall 12 should be read as the second partition wall 28.

[0040] (Gas-liquid separation chamber 6) Explaining with reference to FIG. 4, the gas-liquid separation chamber 6 has an anode-side gas-liquid separation chamber 48 arranged above the anode chamber 8, and a cathode-side gas-liquid separation chamber 50 arranged above the cathode chamber 10.

[0041] (Anode side gas-liquid separation chamber 48) The anode side gas-liquid separation chamber 48 is formed from a first material such as titanium. The anode side gas-liquid separation chamber 48 is defined by an upper end portion of the first partition wall 12 and a first flange 52.

[0042] The first flange 52 includes a top plate 54 extending in direction D from the upper end of the first partition wall 12, a side wall 56 extending downward from the tip of the top plate 54, and a partition plate 58 extending in direction D from the lower end of the side wall 56 toward the first partition wall 12. Although not shown, a protruding piece protruding upward may be provided at the base end of the top plate 54 (the end on the first partition wall 12 side).

[0043] The partition plate 58 is a member that separates the anode chamber 8 from the anode-side gas-liquid separation chamber 48. The partition plate 58 is formed with a passing opening 58a that allows the passage of gas and electrolyte from the anode chamber 8 to the anode-side gas-liquid separation chamber 48. The passing opening 58a is positioned on the anode 14 side in the D direction. A plurality of passing openings 58a are provided at intervals in the W direction.

[0044] The partition plate 58 is further formed with a recovery hole 58b for sending a portion of the electrolyte from the anode-side gas-liquid separation chamber 48 to a first electrolyte recovery means 72 described below. The recovery hole 58b is disposed on the first partition wall 12 side in the direction D. A plurality of recovery holes 58b are provided at intervals in the direction W.

[0045] (Cathode side gas-liquid separation chamber 50) The cathode side gas-liquid separation chamber 50 is formed from a second material such as nickel. The cathode side gas-liquid separation chamber 50 is defined by an upper end portion of the second partition wall 28 and a second flange 60.

[0046] The second flange 60 includes a top plate 62 extending in direction D from the upper end of the second partition wall 28, a side wall 64 extending downward from the tip of the top plate 62, and a partition plate 66 extending in direction D from the lower end of the side wall 64 toward the second partition wall 28. Although not shown, a protruding piece protruding upward may be provided at the base end of the top plate 62 (the end on the second partition wall 28 side).

[0047] (Partition plate 66) The partition plate 66 is a member that separates the cathode chamber 10 from the cathode side gas-liquid separation chamber 50. The partition plate 66 is formed with a passing opening 66a that allows the passage of the electrolyte and gas from the cathode chamber 10 to the cathode side gas-liquid separation chamber 50. The passing opening 66a is positioned on the current collector 30 side in the D direction. A plurality of the passing openings 66a are provided at intervals in the W direction.

[0048] The partition plate 66 is further formed with a recovery hole 66b for sending a portion of the electrolyte from the cathode-side gas-liquid separation chamber 50 to a second electrolyte recovery means 74 described later. The recovery hole 66b is disposed on the second partition wall 28 side in the D direction. A plurality of recovery holes 66b are provided at intervals in the W direction.

[0049] The electrolytic cell unit 2 further includes a supply nozzle for supplying the electrolytic solution into the electrode chamber 4, a dispersion pipe connected to the supply nozzle, and a discharge nozzle for discharging a portion of the gas and electrolytic solution generated by electrolysis from the gas-liquid separation chamber 6. Furthermore, as in the electrolytic cell unit 2 of this embodiment, an electrolyte recovery means may be provided for recovering the electrolyte solution in the gas-liquid separation chamber 6 and returning it to the supply nozzle.

[0050] (Supply nozzle) As shown in FIG. 1, the supply nozzles of the electrolytic cell unit 2 include a first supply nozzle 68 for supplying raw material liquid into the anode chamber 8, and a second supply nozzle 70 for supplying raw material liquid into the cathode chamber 10.

[0051] (First supply nozzle 68) The first supply nozzle 68 is formed from a first material such as titanium, etc. The first supply nozzle 68 extends outward in the W direction from a lower portion of the side surface of the anode chamber 8 (see FIG. 1).

[0052] (Second supply nozzle 70) The second supply nozzle 70 is formed of a second material such as nickel. As shown in FIG. 1, the second supply nozzle 70 extends outward in the W direction from a lower portion of the side surface of the cathode chamber 10, and is disposed on the opposite side to the first supply nozzle 68.

[0053] (Electrolyte recovery means) As shown in Figure 4, the electrolyte recovery means of the electrolytic cell unit 2 includes a first electrolyte recovery means 72 for recovering the electrolyte in the anode side gas-liquid separation chamber 48 and returning it to the first supply nozzle 68, and a second electrolyte recovery means 74 for recovering the electrolyte in the cathode side gas-liquid separation chamber 50 and returning it to the second supply nozzle 70.

[0054] (First electrolyte recovery means 72) The first electrolytic solution recovery means 72 is formed of a first material such as titanium. As shown in Fig. 1 and Fig. 6, the first electrolytic solution recovery means 72 has a horizontal pipe 76 for sending the electrolytic solution recovered from the anode-side gas-liquid separation chamber 48 to one end side in the W direction (the left side in Fig. 1), and a vertical pipe 78 for sending the electrolytic solution sent to the one end side in the W direction to the first supply nozzle 68. The horizontal pipe 76 and the vertical pipe 78 of the first electrolytic solution recovery means 72 may be in contact with the first partition wall 12 or may be separated therefrom.

[0055] The horizontal pipe 76 of the first electrolyte solution recovery means 72 is a channel-shaped member extending in the W direction, and the upper surface of the horizontal pipe 76 is open. As shown in FIG. 4, the horizontal pipe 76 is located below the recovery hole 58b of the partition plate 58 and is connected to the lower surface of the partition plate 58.

[0056] The vertical pipe 78 of the first electrolyte recovery means 72 is a tubular member extending in the V direction (see FIG. 6). An upper part of the vertical pipe 78 communicates with the horizontal pipe 76. A lower part of the vertical pipe 78 communicates with the first supply nozzle 68.

[0057] (Second electrolyte recovery means 74) The second electrolytic solution recovery means 74 is formed of a second material such as nickel. As shown in Fig. 7, the second electrolytic solution recovery means 74 has a horizontal pipe 80 for sending the electrolytic solution recovered from the cathode-side gas-liquid separation chamber 50 to one end side in the W direction, and a vertical pipe 82 for sending the electrolytic solution sent to the one end side in the W direction to the second supply nozzle 70. The horizontal pipe 80 and the vertical pipe 82 of the second electrolytic solution recovery means 74 may be in contact with the second partition wall 28 or may be separated therefrom.

[0058] The horizontal pipe 80 of the second electrolyte recovery means 74 is a channel-shaped member extending in the W direction, and the upper surface of the horizontal pipe 80 is open. As shown in FIG. 4 , the horizontal pipe 80 is located below the recovery hole 66b of the partition plate 66 and is connected to the lower surface of the partition plate 66.

[0059] The vertical pipe 82 of the second electrolyte recovery means 74 is a tubular member extending in the V direction (see FIG. 7). An upper part of the vertical pipe 82 communicates with the horizontal pipe 80. A lower part of the vertical pipe 82 communicates with the second supply nozzle 70.

[0060] (Distributed pipeline) The dispersion pipeline of the electrolytic cell unit 2 in this embodiment includes a first dispersion pipeline 84 (see FIG. 6) connected to the first supply nozzle 68 and the first electrolyte recovery means 72, and a second dispersion pipeline 86 (see FIG. 7) connected to the second supply nozzle 70 and the second electrolyte recovery means 74.

[0061] (1st distribution pipe 84) The first dispersion pipe 84 is formed of a first material such as titanium. As shown in Figures 1 and 6, the first dispersion pipe 84 is connected to the joining portion of the first supply nozzle 68 and the first electrolyte solution recovery means 72. Therefore, the raw material liquid supplied from the first supply nozzle 68 and the electrolyte solution recovered by the first electrolyte solution recovery means 72 are mixed in the first dispersion pipe 84.

[0062] As shown in Figures 5 and 6, the first dispersion pipe 84 has a discharge opening 84a for dispersing and discharging the mixture of the raw material liquid supplied from the first supply nozzle 68 and the electrolyte recovered by the first electrolyte recovery means 72 into the anode chamber 8.

[0063] In this embodiment, the first dispersion pipe 84 extends in the W direction, and the discharge opening 84a also extends in the W direction. This allows the mixed liquid discharged from the discharge opening 84a to spread throughout the entire inside of the anode chamber 8, facilitating the uniformity of the concentration distribution of the raw material liquid in the anode chamber 8.

[0064] It is preferable that the discharge opening 84a extends from one end in the W direction of the first dispersion pipe 84 to the other end in the W direction. Alternatively, a plurality of discharge openings may be formed in the first dispersion pipe 84 at intervals in the W direction.

[0065] 5, the discharge opening 84a faces the anode 14, and the mixed liquid is preferably discharged from the discharge opening 84a toward the anode 14. During electrolysis, gas bubbles are generated at the anode 14. For this reason, by discharging the mixed liquid toward the anode 14, the gas bubbles generated at the anode 14 are carried along with the flow of the mixed liquid discharged from the discharge opening 84a and smoothly rise toward the anode-side gas-liquid separation chamber 48.

[0066] The discharge opening 84a is preferably formed in a lower portion of the first dispersion pipe 84. The mixed liquid discharged from the discharge opening 84a rises toward the anode-side gas-liquid separation chamber 48. Therefore, by forming the discharge opening 84a in the lower portion of the first dispersion pipe 84, it is possible to prevent the mixed liquid from accumulating below the first dispersion pipe 84, etc.

[0067] As shown in FIG. 5, it is desirable to provide gaps between the first dispersion pipe 84 and the anode 14, between the first dispersion pipe 84 and the first partition wall 12, and between the first dispersion pipe 84 and the bottom plate 16 of the anode chamber 8, respectively, through which the mixed liquid discharged from the discharge opening 84a can pass.

[0068] 5, part of the mixed liquid rises immediately after being discharged from the discharge opening 84a, while part of the mixed liquid once falls after being discharged from the discharge opening 84a, then moves in the direction D, and then rises, as shown by arrow A2.

[0069] In other words, a flow (arrow A1) that rises from the release opening 84a side and a flow (arrow A2) that flows around to the opposite side of the release opening 84a and then rises are generated, thereby effectively suppressing stagnation of the mixed liquid below the first dispersion pipe 84, for example.

[0070] (88 drain hole) In the illustrated embodiment, as shown in FIGS. 6 and 8, a liquid drainage hole 88 is provided on the underside of the connection portion C1 between the first supply nozzle 68, the first electrolyte recovery means 72, and the first dispersion pipeline 84.

[0071] When the operation of the electrolytic cell is stopped, the mixed liquid is discharged from the anode chamber 8 and the anode side gas-liquid separation chamber 48 to the outside of the electrolytic cell unit 2 via the first supply nozzle 68 to prevent corrosion of the electrolytic cell unit 2 and to prevent reverse current.

[0072] When the electrolytic cell is shut down, the mixed liquid in the anode chamber 8 flows from the discharge opening 84a into the first dispersion pipe 84 and is then discharged from the first supply nozzle 68. The mixed liquid in the anode-side gas-liquid separation chamber 48 flows into the anode chamber 8 from the passage opening 58a of the partition plate 58 and is then discharged from the first supply nozzle 68 via the first dispersion pipe 84, or flows into the first electrolyte recovery means 72 from the recovery hole 58b of the partition plate 58 and is then discharged from the first supply nozzle 68. In FIG. 8, the flow of the mixed liquid in the anode chamber 8 when the electrolytic cell is shut down is indicated by dotted arrows.

[0073] In this embodiment, by providing the liquid drainage hole 88 on the underside of the connecting portion C1, the mixed liquid present between the first dispersion pipe 84 and the bottom plate 16 of the anode chamber 8 is discharged from the first supply nozzle 68 through the liquid drainage hole 88. This makes it possible to reduce the amount of mixed liquid remaining in the anode chamber 8, effectively preventing corrosion of the electrolytic cell unit 2 and the occurrence of reverse current.

[0074] From the viewpoint of reducing the amount of the mixed liquid remaining in the anode chamber 8, it is preferable that the liquid drainage hole 88 is provided near the bottom plate 16 of the anode chamber 8 (as low as possible).

[0075] (Second distribution pipe 86) The second dispersion pipe 86 is formed of a second material such as nickel. As shown in Fig. 7, the second dispersion pipe 86 is connected to a joining portion of the second supply nozzle 70 and the second electrolytic solution recovery means 74. Therefore, the raw material liquid supplied from the second supply nozzle 70 and the electrolytic solution recovered by the second electrolytic solution recovery means 74 are mixed in the second dispersion pipe 86.

[0076] As shown in FIG. 5, the second dispersion pipe 86 has a discharge opening 86a for dispersing and discharging the mixture of the raw material liquid supplied from the second supply nozzle 70 and the electrolytic solution recovered by the second electrolytic solution recovery means 74 into the cathode chamber 10.

[0077] In this embodiment, the second dispersion pipe 86 extends in the W direction, and the discharge opening 86a also extends in the W direction. This allows the mixed liquid discharged from the discharge opening 86a to spread throughout the entire inside of the cathode chamber 10, facilitating the uniformity of the concentration distribution of the raw material liquid in the cathode chamber 10.

[0078] It is preferable that the discharge opening 86a extends from one end in the W direction of the second dispersion pipe 86 to the other end in the W direction. Alternatively, the second dispersion pipe 86 may have a plurality of discharge openings formed at intervals in the W direction.

[0079] 5, the discharge opening 86a faces the cathode 36, and the mixed liquid is preferably discharged from the discharge opening 86a toward the cathode 36. During electrolysis, gas bubbles are generated at the cathode 36. For this reason, by discharging the mixed liquid toward the cathode 36, the gas bubbles generated at the cathode 36 are carried by the flow of the mixed liquid discharged from the discharge opening 86a and smoothly rise toward the cathode-side gas-liquid separation chamber 50.

[0080] The discharge opening 86a is preferably formed in a lower portion of the second dispersion pipe 86. The mixed liquid discharged from the discharge opening 86a rises toward the cathode-side gas-liquid separation chamber 50. Therefore, by forming the discharge opening 86a in the lower portion of the second dispersion pipe 86, it is possible to prevent the mixed liquid from accumulating below the second dispersion pipe 86, etc.

[0081] As shown in FIG. 5, it is desirable to provide gaps between the second dispersion pipe 86 and the cathode 36, between the second dispersion pipe 86 and the second partition wall 28, and between the second dispersion pipe 86 and the bottom plate 32 of the cathode chamber 10, respectively, through which the mixed liquid discharged from the discharge opening 86a can pass.

[0082] 5, part of the mixed liquid rises immediately after being discharged from the discharge opening 86a, while part of the mixed liquid once falls after being discharged from the discharge opening 86a, then moves in the direction D, and then rises, as shown by arrow A4.

[0083] In other words, a flow (arrow A3) that rises from the discharge opening 86a side and a flow (arrow A4) that flows around to the opposite side of the discharge opening 86a and then rises are generated, thereby effectively suppressing stagnation of the mixed liquid below the second dispersion pipe 86, for example.

[0084] (90mm drain hole) In the illustrated embodiment, as shown in FIGS. 7 and 9, a liquid drainage hole 90 is provided on the underside of the connection C2 between the second supply nozzle 70, the second electrolyte recovery means 74, and the second dispersion pipeline 86.

[0085] When the operation of the electrolytic cell is stopped, the mixed liquid is discharged from the cathode chamber 10 and the cathode side gas-liquid separation chamber 50 to the outside of the electrolytic cell unit 2 via the second supply nozzle 70 to prevent corrosion of the electrolytic cell unit 2 and to prevent reverse current.

[0086] Specifically, the mixed liquid in the cathode chamber 10 flows from the discharge opening 86a into the second dispersion pipe 86 and is then discharged from the second supply nozzle 70. The mixed liquid in the cathode-side gas-liquid separation chamber 50 flows from the passage opening 66a of the partition plate 66 into the cathode chamber 10 and is then discharged from the second supply nozzle 70 via the second dispersion pipe 86, or flows from the recovery hole 66b of the partition plate 66 into the second electrolyte recovery means 74 and is then discharged from the second supply nozzle 70. In FIG. 9, the flow of the mixed liquid in the cathode chamber 10 during shutdown is indicated by dotted arrows.

[0087] In this embodiment, by providing the liquid drainage hole 90 on the underside of the connecting part C2, the mixed liquid present between the second dispersion pipe 86 and the bottom plate 32 of the cathode chamber 10 is discharged from the second supply nozzle 70 through the liquid drainage hole 90. This makes it possible to reduce the amount of mixed liquid remaining in the cathode chamber 10, thereby effectively preventing corrosion of the electrolytic cell unit 2 and the occurrence of reverse current.

[0088] From the viewpoint of reducing the amount of the mixed liquid remaining in the cathode chamber 10, the liquid drainage hole 90 is preferably provided near the bottom plate 32 of the cathode chamber 10 (as low as possible).

[0089] (Discharge nozzle) As shown in FIG. 1, the discharge nozzles of the electrolytic cell unit 2 include a first discharge nozzle 92 for discharging the gas and electrolytic solution from the anode-side gas-liquid separation chamber 48, and a second discharge nozzle 94 for discharging the gas and electrolytic solution from the cathode-side gas-liquid separation chamber 50.

[0090] (Lower frame 96, side frame 98) As shown in Fig. 2, a hollow lower frame 96 having a rectangular cross section is provided at the bottom of the electrolytic cell unit 2. In addition, hollow horizontal frames 98 having a rectangular cross section are provided at both end portions in the W direction of the electrolytic cell unit 2 (see Figs. 8 and 9). The lower frame 96 and the horizontal frames 98 may be formed from a metal material such as stainless steel.

[0091] (electrolytic cell) When assembling an electrolytic cell, a large number of the electrolytic cell units 2 described above are prepared, and the large number of electrolytic cell units 2 are arranged in direction D so that the anode 14 and the cathode 36 face each other, and an ion exchange membrane or diaphragm (not shown) is disposed between the anode 14 and the cathode 36. The ion exchange membrane is used in the case of electrolysis of an alkali metal chloride aqueous solution. On the other hand, the diaphragm is used in the case of electrolysis of an alkali metal hydroxide aqueous solution. Then, the large number of electrolytic cell units 2 are pressed from both sides in direction D using a hydraulic press or the like. In addition, flow path members such as hoses are connected to the first and second supply nozzles 68, 70 and the first and second discharge nozzles 92, 94.

[0092] (electrolytic) When electrolysis is performed in the electrolytic cell, the raw material liquid is supplied to the anode chamber 8 via the first supply nozzle 68 and the first dispersion pipe 84. Also, the raw material liquid is supplied to the cathode chamber 10 via the second supply nozzle 70 and the second dispersion pipe 86. Then, a voltage is applied to the anode 14 and the cathode 36. This causes gas to be generated at the anode 14 and the cathode 36, producing an electrolytic solution containing a large number of gas bubbles.

[0093] (Flow of electrolyte generated in anode chamber 8) The bubble-containing electrolyte produced in the anode chamber 8 passes through the passage opening 58a of the partition plate 58 and flows into the anode-side gas-liquid separation chamber 48, where it is separated into gas and liquid and then discharged from the first discharge nozzle 92. However, a portion of the electrolyte that has flowed into the anode-side gas-liquid separation chamber 48 flows out from the recovery hole 58b of the partition plate 58 and is returned to the first supply nozzle 68 by the first electrolyte recovery means 72.

[0094] That is, a portion of the electrolyte that has flowed into the anode-side gas-liquid separation chamber 48 flows out into the horizontal pipe 76 of the first electrolyte recovery means 72 through the recovery hole 58b of the partition plate 58. The electrolyte that has flowed out into the horizontal pipe 76 is sent to one end in the W direction, and then sent to the first supply nozzle 68 by the vertical pipe 78.

[0095] Therefore, the electrolytic solution recovered by the first electrolytic solution recovery means 72 is mixed with the raw material solution supplied from the first supply nozzle 68 in the first dispersion pipe 84. Then, the mixture of the electrolytic solution and the raw material solution is dispersed and discharged from the discharge opening 84a of the first dispersion pipe 84 into the anode chamber 8.

[0096] In this manner, in the present embodiment, the mixed liquid is dispersed and discharged into the anode chamber 8 from the discharge opening 84a of the first dispersion pipe 84, which promotes uniformity of the concentration distribution of the raw material liquid in the anode chamber 8. Therefore, it is possible to suppress a decrease in the efficiency of electrolysis.

[0097] In the present embodiment, the discharge opening 84a faces the anode 14, and the mixed liquid is discharged from the discharge opening 84a toward the anode 14. Therefore, gas bubbles generated at the anode 14 are carried by the flow of the mixed liquid discharged from the discharge opening 84a and smoothly rise toward the anode-side gas-liquid separation chamber 48.

[0098] Furthermore, since the discharge opening 84a in this embodiment is formed in the lower portion of the first dispersion pipe 84, it is possible to prevent the mixed liquid from accumulating below the first dispersion pipe 84, for example.

[0099] As described above, in this embodiment, gaps through which the mixed liquid released from the release opening 84a can pass are provided between the first dispersion pipe 84 and the anode 14, between the first dispersion pipe 84 and the first partition wall 12, and between the first dispersion pipe 84 and the bottom plate 16 of the anode chamber 8.

[0100] This creates a flow (arrow A1) that rises from the release opening 84a side and a flow (arrow A2) that flows around to the opposite side of the release opening 84a and then rises, effectively preventing the mixed liquid from stagnating.

[0101] (Flow of electrolyte generated in cathode chamber 10) The bubble-containing electrolyte produced in the cathode chamber 10 passes through the passage opening 66a of the partition plate 66 and flows into the cathode-side gas-liquid separation chamber 50, where it is separated into gas and liquid and then discharged from the second discharge nozzle 94. However, a portion of the electrolyte that has flowed into the cathode-side gas-liquid separation chamber 50 flows out from the recovery hole 66b of the partition plate 66 and is returned to the second supply nozzle 70 by the second electrolyte recovery means 74.

[0102] That is, a portion of the electrolytic solution that has flowed into the cathode-side gas-liquid separation chamber 50 flows out into the horizontal pipe 80 of the second electrolytic solution recovery means 74 through the recovery hole 66b of the partition plate 66. The electrolytic solution that has flowed out into the horizontal pipe 80 is sent to one end side in the W direction, and then sent to the second supply nozzle 70 by the vertical pipe 82.

[0103] Therefore, the electrolytic solution recovered by the second electrolytic solution recovery means 74 is mixed with the raw material liquid supplied from the second supply nozzle 70 in the second dispersion pipe 86. Then, the mixture of the electrolytic solution and the raw material liquid is dispersed and discharged from the discharge opening 86a of the second dispersion pipe 86 into the cathode chamber 10.

[0104] In this manner, in the present embodiment, the mixed liquid is dispersed and discharged into the cathode chamber 10 from the discharge opening 86a of the second dispersion pipe 86, which promotes uniformity of the concentration distribution of the raw material liquid in the cathode chamber 10. Therefore, it is possible to suppress a decrease in the efficiency of electrolysis.

[0105] In the present embodiment, the discharge opening 86a faces the cathode 36, and the mixed liquid is discharged from the discharge opening 86a toward the cathode 36. Therefore, gas bubbles generated at the cathode 36 are carried by the flow of the mixed liquid discharged from the discharge opening 86a and smoothly rise toward the cathode-side gas-liquid separation chamber 50.

[0106] Furthermore, since the discharge opening 86a in this embodiment is formed in the lower portion of the second dispersion pipe 86, it is possible to prevent the mixed liquid from accumulating below the second dispersion pipe 86, for example.

[0107] As described above, in the present embodiment, gaps through which the mixed liquid released from the release opening 86a can pass are provided between the second dispersion pipe 86 and the cathode 36, between the second dispersion pipe 86 and the second partition wall 28, and between the second dispersion pipe 86 and the bottom plate 32 of the cathode chamber 10.

[0108] This creates a flow (arrow A3) that rises from the release opening 86a side and a flow (arrow A4) that flows around to the opposite side of the release opening 86a and then rises, effectively preventing the mixed liquid from stagnating.

[0109] As described above, in the electrolytic cell unit 2, the mixed solution of the raw material liquid and the electrolytic solution is dispersed and discharged from the discharge opening 84a of the first dispersion pipe 84 into the anode chamber 8, which promotes uniformity of the concentration distribution of the raw material liquid in the anode chamber 8. Furthermore, the mixed solution of the raw material liquid and the electrolytic solution is dispersed and discharged from the discharge opening 86a of the second dispersion pipe 86 into the cathode chamber 10, which promotes uniformity of the concentration distribution of the raw material liquid in the cathode chamber 10. Therefore, a decrease in the efficiency of electrolysis can be suppressed.

[0110] However, in areas where the concentration of the raw material solution is low, the damage to the membrane caused by electrolysis is relatively large, and localized membrane damage is likely to occur early. Such membrane damage is particularly noticeable in the electrolysis of an aqueous solution of an alkali metal chloride.

[0111] In the present embodiment, as described above, the uniformity of the concentration distribution of the raw material solution is promoted, so that early damage to the membrane can be prevented, which is particularly effective in the case of electrolysis of an aqueous solution of an alkali metal chloride, in which early damage to the ion exchange membrane is prominent.

[0112] The above-mentioned embodiment is merely a preferred embodiment of the present invention, and the present invention is not limited to the above-mentioned embodiment. For example, the electrolytic cell unit of the present invention may not be provided with an electrolyte recovery means, and may not be provided with the second dispersion pipe 86.

[0113] First, regarding the electrolyte recovery means, both the first electrolyte recovery means 72 and the second electrolyte recovery means 74 do not have to be provided. This is because, even without the first electrolyte recovery means 72, the raw material solution supplied from the first supply nozzle 68 is dispersed and discharged from the discharge opening 84a of the first dispersion pipe 84 into the anode chamber 8, which can promote uniformity of the concentration distribution of the raw material solution in the anode chamber 8. Similarly, even without the second electrolyte recovery means 74, the raw material solution supplied from the second supply nozzle 70 is dispersed and discharged from the discharge opening 86a of the second dispersion pipe 86 into the cathode chamber 10, which can promote uniformity of the concentration distribution of the raw material solution in the cathode chamber 10.

[0114] Alternatively, only either the first electrolytic solution recovery means 72 or the second electrolytic solution recovery means 74 may be provided, without the other of the first electrolytic solution recovery means 72 or the second electrolytic solution recovery means 74.

[0115] When the first electrolyte recovery means 72 is not provided, the first dispersion pipe 84 may be connected to the side wall 18 or the bottom plate 16, and may be held using a support material attached to the side wall 18, the bottom plate 16, or the partition wall 12. When the second electrolyte recovery means 74 is not provided, the second dispersion pipe 86 may be connected to the side wall 38 or the bottom plate 32, and may be held using a support material attached to the side wall 38, the bottom plate 32, or the partition wall 28.

[0116] If there is no first electrolyte recovery means 72, the recovery hole 58b may not be formed in the partition plate 58. Similarly, if there is no second electrolyte recovery means 74, the recovery hole 66b may not be formed in the partition plate 66.

[0117] Next, regarding the dispersion pipes, the first dispersion pipe 84 is provided in the anode chamber 8, and the second dispersion pipe 86 may not be provided in the cathode chamber 10. For example, in the case of sodium chloride electrolysis, chlorine is generated on the anode 14 side and sodium ions move to the cathode 36 side, so that the NaCl concentration on the anode 14 side changes rapidly. On the other hand, in sodium chloride electrolysis, the concentration change on the cathode 36 side is smaller than the concentration change on the anode 14 side. Therefore, if the first dispersion pipe 84 is provided in the anode chamber 8, the effect of the rapid change in the NaCl concentration on the anode 14 side can be minimized. In other words, the concentration in the anode chamber 8 can be quickly made uniform. Therefore, even if the second dispersion pipe 86 is not provided in the cathode chamber 10, if the anode chamber 8 has the first dispersion pipe 84, it is possible to prevent early local damage to the membrane.

[0118] However, even when the second dispersion pipe 86 is not provided, it is preferable to provide the second electrolyte solution recovery means 74 (see Figs. 10 and 11). This is because returning the electrolyte recovered by the second electrolyte solution recovery means 74 to the second supply nozzle 70 can promote uniform concentration in the cathode chamber 10. When the second dispersion pipe 86 is not provided, the vertical pipe 82 of the second electrolyte solution recovery means 74 may be connected to the second supply nozzle 70 as shown in Fig. 10, or may not be connected to the second supply nozzle 70 as shown in Fig. 11.

[0119] In addition to sodium chloride electrolysis, there are cases where the second dispersion pipe 86 does not need to be provided in the cathode chamber 10. That is, these are cases where electrolysis is applied in which the concentration change on the cathode 36 side is smaller than the concentration change on the anode 14 side. In such cases, only the first dispersion pipe 84 is provided in the anode chamber 8, and the second dispersion pipe 86 does not need to be provided in the cathode chamber 10. [Explanation of symbols]

[0120] 2: Electrolyzer unit 4: Electrode chamber 6: Gas-liquid separation chamber 8:Anode chamber 10: Cathode chamber 12:First bulkhead 14: Anode 16: Bottom plate 28:Second bulkhead 32: Bottom plate 36: Cathode 48:Anode side gas-liquid separation chamber 50: Cathode side gas-liquid separation chamber 58: Partition board 58b: Recovery hole 66: Partition board 66b: Recovery hole 68: First supply nozzle 70: Second supply nozzle 72: First electrolyte recovery means 74: Second electrolyte recovery means 76: Horizontal pipe 78: Vertical pipe 80: Horizontal pipe 82: Vertical pipe 84: 1st distribution pipe 84a: Release aperture 86:Second distribution pipe 86a: Release aperture 88: Drain hole 90: Drain hole C1: Connection part C2: Connection part

Claims

1. an electrode chamber in which an electrode is installed; a gas-liquid separation chamber disposed above the electrode chamber; a supply nozzle for supplying a raw material liquid into the electrode chamber; a dispersion pipe connected to the supply nozzle; The dispersion pipeline is an electrolytic cell unit having a discharge opening for dispersing and discharging the raw material liquid supplied from the supply nozzle into the electrode chamber.

2. The electrolytic cell unit according to claim 1 , wherein the supply nozzle extends from a lower portion of a side surface of the electrode chamber outward in a width direction of the electrolytic cell unit.

3. 2. The electrolytic cell unit of claim 1, wherein the dispersion conduit extends across the width of the electrolytic cell unit and the discharge opening also extends across the width of the electrolytic cell unit.

4. 2. The electrolytic cell unit according to claim 1, wherein the dispersion pipe extends in a width direction of the electrolytic cell unit, and a plurality of the discharge openings are formed at intervals in the width direction of the electrolytic cell unit.

5. The electrolytic cell unit according to claim 1 , wherein the discharge opening faces the electrode, and the raw material solution is discharged from the discharge opening toward the electrode.

6. 2. The electrolytic cell unit according to claim 1, wherein the discharge opening is formed in a lower portion of the dispersion conduit.

7. the electrode chamber includes a partition wall disposed at a distance from the electrode in a depth direction of the electrolytic cell unit, 2. The electrolytic cell unit according to claim 1, wherein a gap through which the raw material liquid discharged from the discharge opening can pass is provided between the dispersion pipe and the electrode, between the dispersion pipe and the partition wall, and between the dispersion pipe and a bottom plate of the electrode chamber.

8. a liquid drain hole is provided at a connection between the supply nozzle and the dispersion pipe, 8. The electrolytic cell unit according to claim 7, wherein when the raw material liquid is discharged from the electrode chamber and the gas-liquid separation chamber via the supply nozzle, the raw material liquid present between the dispersion pipe and the bottom plate of the electrode chamber is sent to the supply nozzle through the liquid drainage hole.

9. further comprising an electrolyte recovery means for recovering the electrolyte in the gas-liquid separation chamber and returning it to the supply nozzle, 2. The electrolytic cell unit according to claim 1, wherein a mixture of the raw material liquid supplied from the supply nozzle and the electrolyte recovered by the electrolyte recovery means is discharged into the electrode chamber from the discharge opening of the dispersion pipeline.

10. The electrode chamber includes an anode chamber in which an anode is installed and a cathode chamber in which a cathode is installed, the gas-liquid separation chamber has an anode-side gas-liquid separation chamber disposed above the anode chamber and a cathode-side gas-liquid separation chamber disposed above the cathode chamber, the supply nozzle includes a first supply nozzle for supplying a raw material liquid into the inside of the anode chamber and a second supply nozzle for supplying a raw material liquid into the inside of the cathode chamber, the electrolytic solution recovery means includes a first electrolytic solution recovery means that recovers the electrolytic solution in the anode-side gas-liquid separation chamber and returns it to the first supply nozzle, and a second electrolytic solution recovery means that recovers the electrolytic solution in the cathode-side gas-liquid separation chamber and returns it to the second supply nozzle, 10. The electrolyzer unit of claim 9, wherein the dispersion conduit is connected to the first supply nozzle.

11. 10. The electrolytic cell unit according to claim 9, wherein a recovery hole is formed in a partition plate that separates the electrode chamber from the gas-liquid separation chamber, and the electrolyte recovery means recovers the electrolyte that has flowed out from the recovery hole and returns it to the supply nozzle.

12. 10. The electrolytic cell unit according to claim 9, wherein the electrolyte recovery means has a horizontal pipeline for sending the electrolyte recovered from the gas-liquid separation chamber to one end in the width direction, and a vertical pipeline for returning the electrolyte sent to the one end in the width direction to the supply nozzle.

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