Electrolysis device

Abstract

To provide an electrolysis device that can employ another arrangement method (device configuration) other than a method of arranging individual device members whereby an electrolytic solution is made to circulate between an electrolytic tank and a gas / liquid separation tank using one pump.SOLUTION: An electrolytic device (1, 1A or 1B), comprises an electrolytic tank (4) electrolyzing an electrolyte solution to generate electrolytic solution including gas, a gas / liquid separation tank (5) separating gas from the electrolytic solution sent from the electrolytic tank (4) to produce the electrolyte solution, an electrolyte solution storage tank (2) storing the electrolyte solution sent from the gas / liquid separation tank (5), and a pump (3) sucking the electrolyte solution from the electrolyte solution storage tank (2) to send the electrolyte solution to the electrolytic tank (4). The gas / liquid separation tank (5) comprises an outflow port (52) through which the electrolyte solution outflowing into the electrolyte solution storage tank (2) flows, with a feed port (21) feeding the electrolyte solution from the gas / liquid separation tank (5) into the electrolyte solution storage tank (2), being disposed on a higher position relative to the outflow port (52), in the electrolyte solution storage tank (2).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electrolysis device. [Background technology]

[0002] Conventionally, there is known an apparatus equipped with an electrolytic cell and a gas-liquid separation cell (for example, Patent Document 1). In this apparatus, an electrolyte solution is sent to the electrolytic cell and electrolyzed to become an electrolyte solution containing generated gas, which is sent to the gas-liquid separation cell. The gas is separated from the electrolyte solution containing gas in the gas-liquid separation cell, which becomes an electrolyte solution and is sent back to the electrolytic cell. [Prior art documents] [Patent documents]

[0003] JP 2011-087468 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the device of Patent Document 1, a pump directly sucks the electrolyte solution from the gas-liquid separation tank and sends it to the electrolytic cell, thereby circulating the electrolyte solution (the electrolyte solution after gas-liquid separation process is described above as the electrolyte solution) between the electrolytic cell and the gas-liquid separation tank. In an electrolytic device, there is a large amount of room for variation in the arrangement of each device component (electrolytic cell, etc.), and there is a possibility that merit can be obtained by adopting an arrangement method (device configuration) other than the arrangement method of each device component that circulates the electrolyte solution between two elements with such a single pump. [Means for solving the problem]

[0005] The invention is, for example, as follows: In the following, the reference numbers of the figures are used for reference. (1) an electrolytic cell (4) for electrolyzing an electrolyte solution to generate an electrolyte solution containing a gas; a gas-liquid separation tank (5) for separating gas from the electrolytic solution sent from the electrolytic tank (4) to produce an electrolytic solution; an electrolyte solution storage tank (2) for storing the electrolyte solution sent from the gas-liquid separation tank (5); a pump (3) for sucking the electrolyte solution from the electrolyte solution storage tank (2) and sending it to the electrolytic cell (4); The gas-liquid separation tank (5) has an outlet (52) through which the electrolyte solution flows into the electrolyte solution storage tank (2), In the electrolysis device (1, 1A, 1B), a supply port (21) for supplying the electrolyte solution from the gas-liquid separation tank (5) into the electrolyte solution storage tank (2) is provided at a position higher than the outlet (52) in the electrolyte solution storage tank (2). (2) In the electrolysis device (1, 1A, 1B) according to (1), the electrolysis device (1, 1A, 1B) including a crank-shaped first pipe (64) connecting the gas-liquid separation tank (5) and the electrolyte solution storage tank (2) and connected to the outlet (52) and the supply port (21); (3) In the electrolysis apparatus (1B) according to (1), a second pipe (62) for delivering the electrolyte solution discharged from the pump (3) to the electrolytic cell (4); a third pipe (63) for conveying the electrolytic solution from the electrolytic cell (4) to the gas-liquid separation cell (5); and a fourth pipe (67) branching off from the second pipe (62), bypassing the electrolytic cell (4), and joining the third pipe (63). (4) In the electrolysis device (1, 1A, 1B) according to any one of (1) to (3), The electrolyte solution storage tank (2) is an electrolysis device (1, 1A, 1B) that discharges gas separated from the stored electrolyte solution to the outside. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a diagram showing a configuration of an electrolysis device. [Diagram 2] FIG. 1 is a diagram showing an electrolysis device provided with a plurality of sets of gas-liquid separation tanks and electrolyte solution storage tanks. [Diagram 3]FIG. 13 is a diagram showing an electrolysis device in which a bypass for the electrolytic cell is provided in the flow path of the electrolytic solution from the pump to the gas-liquid separation cell. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] FIG. 1 is a diagram showing the configuration of an electrolysis device 1. In this specification, electrolysis is basically referred to as electrolysis. Basically, an electrolyte solution that has been electrolytically treated is called an "electrolyte", and an electrolyte solution that has been gas-liquid separated is called an "electrolyte solution". However, when it is desired to collectively express the liquid circulating in the electrolysis device 1, the "electrolyte" and the "electrolyte solution" may be collectively referred to as the "electrolyte solution". In the electrolysis device 1, an electrolyte solution storage tank 2, a pump 3, an electrolytic cell 4, and a gas-liquid separation tank 5 are provided in this order in the flow direction of the electrolyte in an electrolyte circulation flow path 6. The circulation flow path 6 includes a pipe 61 connecting the electrolyte solution storage tank 2 and the pump 3, a pipe 62 connecting the pump 3 and the electrolytic cell 4, a pipe 63 connecting the electrolytic cell 4 and the gas-liquid separation tank 5, and a pipe 64 (first pipe) connecting the gas-liquid separation tank 5 and the electrolyte solution storage tank 2.

[0008] The electrolyte solution storage tank 2 stores the electrolyte solution. The electrolyte solution is water containing an electrolyte such as NaOH that does not contain halides, but any other electrolyte solution can be used. The electrolyte solution storage tank 2 has a supply port 21 that supplies the electrolyte solution from the gas-liquid separation tank 5 into the electrolyte solution storage tank 2. The supply port 21 is provided, for example, on the inner peripheral wall of the electrolyte solution storage tank 2. The electrolyte solution from the gas-liquid separation tank 5 still contains gas, although the contained gas is separated in the gas-liquid separation tank 5. Therefore, in the electrolyte solution storage tank 2, separation of the contained gas in the electrolyte solution progresses, and the separated gas accumulates in the upper part of the electrolyte solution storage tank 2. The separated gas is, for example, hydrogen gas and oxygen gas. The electrolyte solution storage tank 2 discharges the separated gas to the outside through a pipe 22 connected to the upper part of the electrolyte solution storage tank 2. The electrolyte solution storage tank 2 is provided with a relief valve 24 that opens to suck in the air when the upper space of the electrolyte solution storage tank 2 falls below a set pressure.

[0009] The electrolyte solution storage tank 2 has an outlet 23 at its bottom, which is connected to a pipe 61. The outlet 23 is located lower than the outlet 21 and is provided, for example, on the bottom surface of the inner wall of the electrolyte solution storage tank 2, but may be provided in the lower part of the inner wall. The electrolyte solution in the electrolyte solution storage tank 2 is sent to the pump 3 via the outlet 23 and the pipe 61.

[0010] The pump 3 draws the electrolyte solution from the electrolyte solution storage tank 2 via a pipe 61 , and delivers the electrolyte solution to the electrolytic cell 4 via a pipe 62 .

[0011] The electrolytic cell 4 is a so-called single-chamber type, and an anode and a cathode are housed in the electrolytic cell body that stores the electrolyte solution, without being partitioned by a diaphragm. In the electrolytic cell 4, for example, oxygen gas bubbles are generated at the anode and hydrogen gas bubbles are generated at the cathode by electrolysis. In this way, the electrolytic cell 4 electrolyzes the electrolyte solution to generate an electrolyte solution containing gas. The electrolyte solution containing the gas generated by electrolysis is sent from the electrolytic cell 4 to the gas-liquid separation cell 5 via piping 63.

[0012] The gas-liquid separation tank 5 separates the contained gas from the electrolyte solution sent from the electrolytic cell 4 to generate an electrolyte solution. The contained gas of the electrolyte solution collected in the gas-liquid separation tank 5 and the contained gas of the electrolyte solution collected in the electrolyte solution storage tank 2 are, for example, hydrogen gas and oxygen gas, and can be used as combustion gas. The gas-liquid separation tank 5 is, for example, a long cylinder in the vertical direction. The bottom surface of the inner wall of the gas-liquid separation tank 5 and the bottom surface of the inner wall of the electrolyte solution storage tank 2 are at the same height position, but may be at different height positions. At the top of the gas-liquid separation tank 5, there is a supply port 51 for the electrolyte solution from the electrolytic cell 4. The liquid level of the electrolyte solution in the gas-liquid separation tank 5 is set at a position higher than the supply port 51. This has the effect of promoting the coagulation of the gas contained in the electrolyte solution by supplying the electrolyte solution electrolyzed by the electrolytic cell 4 to the liquid region of the gas-liquid separation tank 5.

[0013] At the bottom of the gas-liquid separation tank 5, there is an outlet 52 through which the electrolyte solution flows out into the electrolyte solution storage tank 2. The outlet 52 is provided, for example, at the bottom of the inner circumferential wall of the gas-liquid separation tank 5. In this embodiment, the outlet 52 is located higher than the outlet 23 at the bottom of the electrolyte solution storage tank 2, but it may be located lower than the outlet 23. One end of the piping 64 is connected to the outlet 52 of the gas-liquid separation tank 5, and the other end is connected to the supply port 21 of the electrolyte solution storage tank 2.

[0014] Here, the supply port 21 of the electrolyte solution storage tank 2 is located at a higher position than the outlet 52 of the gas-liquid separation tank 5. Thus, the piping 64 connecting the two is made of polyvinyl chloride and has a crank shape in this embodiment, but it may also be made of polyvinyl chloride and have an S-shape, and the piping 64 may also be a metal pipe or a hose made of a flexible material such as rubber.

[0015] As the electrolyte moves from the top to the bottom in the gas-liquid separation tank 5, the contained gas is separated from the electrolyte. The separated gas accumulates in the upper part of the gas-liquid separation tank 5. The separated gas is, for example, hydrogen gas and oxygen gas, and is discharged to the outside via a pipe 53 connected to the top of the gas-liquid separation tank 5. A pipe 65 is connected to the bottom of the gas-liquid separation tank 5. The pipe 65 merges with a pipe 61. By opening a valve 66 in the middle of the pipe 65, the electrolyte solution that has been subjected to the gas-liquid separation process in the gas-liquid separation tank 5 can be made to flow to the pump 3 via the pipe 61.

[0016] In Patent Document 1, the electrolyte is circulated in a circulation flow path having an electrolytic cell and a gas-liquid separation cell, and is repeatedly used for electrolysis, and gases such as hydrogen gas and oxygen gas are generated and contained in the electrolyte, and the gases are separated from the electrolyte in the gas-liquid separation cell and collected. In the configuration of Patent Document 1, there is a risk that pulsation (pressure fluctuation) occurs in the electrolyte circulation flow path due to the pump discharge operation, or that cavitation occurs in the pump.

[0017] In the configuration of Patent Document 1, the supply port of the electrolyte solution to the inside of the gas-liquid separation tank is located on the bottom surface of the inner wall in order to secure separation time. In addition, in the gas-liquid separation tank, the outlet of the electrolyte solution to the electrolytic tank is also located on the bottom surface of the inner wall in order to prevent the separated gas from being sucked out. Although the gas-liquid separation process in the gas-liquid separation tank requires a certain time, in Patent Document 1, after being supplied from the supply port on the bottom surface of the inner wall, a part of the electrolyte solution is likely to flow out from the outlet on the bottom surface of the inner wall without staying in the gas-liquid separation tank for a certain time, and there is room for improvement in the gas-liquid separation efficiency.

[0018] In this embodiment, an electrolyte solution storage tank 2 is provided downstream of a gas-liquid separation tank 5, and a pump 3 sucks the electrolyte solution from the electrolyte solution storage tank 2. Here, the supply force of the electrolyte solution from a supply port 21 to the electrolyte solution storage tank 2 is smaller than the suction force of the pump 3 applied to an outlet 23 directly connected to the pump 3, because the gas-liquid separation tank 5 and the electrolytic cell 4 provide resistance to the extrusion of the electrolyte solution between the pump 3 and the supply port 21, and the relationship between the two is as follows: Suction force of pump 3 applied to outlet 23>supply force of electrolyte solution from supply port 21 to electrolyte solution storage tank 2

[0019] The force of pump 3 pushing out the electrolyte solution reaching gas-liquid separation tank 5 is reduced by the resistance provided by electrolytic tank 4. As a result, the amount of electrolyte solution flowing into gas-liquid separation tank 5 (the amount of electrolyte solution flowing out from outlet 52 of gas-liquid separation tank 5) is smaller than the amount of electrolyte solution pushed out by pump 3 (the amount of electrolyte solution sucked by pump 3 from outlet 23 directly connected to pump 3), and the relationship between the two is as follows: Discharge rate of pump 3 (amount of suction of pump 3 from outlet 23)>inflow rate of electrolyte solution into gas-liquid separation tank 5 (amount of electrolyte solution flowing out from outlet 52 of gas-liquid separation tank 5)

[0020] Under these conditions, when the pump 3 is operated with the electrolyte solution accumulated in the gas-liquid separation tank 5 and the electrolyte solution storage tank 2, the pulsation in the circulation flow path 6 can be mitigated in the electrolyte solution storage tank 2. By providing the electrolyte solution storage tank 2 separately from the gas-liquid separation tank 5, the flow pressure of the electrolyte solution in the electrolyte solution storage tank 2 can be adjusted by selecting the electrolyte solution storage tank 2, setting the operating conditions of the pump 3, etc. so that it is as close to the flow pressure of the electrolyte solution in the gas-liquid separation tank 5 as possible, thereby suppressing the pulsation in the circulation flow path 6.

[0021] In this embodiment, the pump 3 sucks the electrolyte solution from the electrolyte solution storage tank 2 provided separately from the gas-liquid separation tank 5. Since a part of the amount of electrolyte required to circulate is stored in the electrolyte solution storage tank 2, the capacity of the gas-liquid separation tank 5 can be reduced by that amount, and the gas-liquid separation tank 5 can be made smaller.

[0022] By miniaturizing the gas-liquid separation tank 5, the ratio of the electrolyte storage portion in the internal space of the gas-liquid separation tank 5 increases, so that the degree of freedom of the formation position of the electrolyte supply port 51 increases, and the connection of the pipe 63 connected to the supply port 51 to the gas-liquid separation tank 5 becomes easy. Note that, if the electrolyte can be stored in the gas-liquid separation tank 5 only by the height H of the crank part of the pipe 64, that is, the height H from the outlet 23 to the supply port 21, the electrolyte can be circulated in the circulation flow path 6. Therefore, the gas-liquid separation tank 5 only needs to have a height H of the crank part of the pipe 64 and a height of the gas retention space. In addition, the liquid levels of the electrolyte in the gas-liquid separation tank 5 and the electrolyte solution in the electrolyte solution storage tank 2 are at a position equal to or higher than the height H and at the same height. Here, for example, if the bottom surface of the inner wall of the electrolyte solution storage tank 2 is positioned higher than the bottom surface of the inner wall of the gas-liquid separation tank 5, the path of the electrolyte solution in the electrolyte solution storage tank 2 will be shortened by the difference in their positions, and the gas-liquid separation time in the electrolyte solution storage tank 2 will be reduced, but this makes it possible to select a smaller suction amount of the pump 3. In this way, adjusting the height of the outlet 23 at the bottom of the electrolyte solution storage tank 2 also has the effect of allowing the selection of the pump 3.

[0023] In the electrolyte solution storage tank 2, the supply port 21 is located higher than the outlet 52 of the gas-liquid separation tank 5 and is located at a sufficiently high position within the gas-liquid separation tank 5, so that the electrolyte solution can be stored sufficiently in the electrolyte solution storage tank 2. This makes it easy to adjust the flow rate of the pump 3, which in turn makes it easy to suppress pulsation in the circulation flow path 6 by adjusting the flow rate of the pump 3. Furthermore, since the electrolyte solution can be stored sufficiently in the electrolyte solution storage tank 2 and the suction flow rate of the pump 3 can be sufficiently ensured, the occurrence of cavitation in the pump 3 can be suppressed.

[0024] Since the electrolyte solution is also stored in the electrolyte solution storage tank 2 directly connected to the gas-liquid separation tank 5, the residence time of the electrolyte solution for gas-liquid separation can be increased, and the efficiency of gas-liquid separation can be improved. In addition, since a sufficient amount of electrolyte solution can be stored in the electrolyte solution storage tank 2, the residence time of the electrolyte solution in the electrolyte solution storage tank 2 can also be increased, which also improves gas-liquid separation.

[0025] The electrolyte solution storage tank 2 stores the electrolyte solution from which gas has been separated and further performs gas-liquid separation processing, so that the amount of gas separated is smaller than that in the gas-liquid separation tank 5. In this embodiment, the pump 3 sucks out the electrolyte solution from the electrolyte solution storage tank 2, so that the amount of separated gas sucked in by the pump 3 can be reduced, and thus the electrolysis efficiency in the electrolytic tank 4 can be maintained at a good level. In addition, because the amount of separated gas sucked out by the pump 3 can be reduced, the range of options for the pump 3 can be expanded.

[0026] As shown in Fig. 2, a plurality of sets of a gas-liquid separation tank 5 and an electrolyte solution storage tank 2 may be provided in parallel with respect to an electrolytic tank 4 and a pump 3 on a circulation flow path 6A of the electrolyte solution. In the electrolytic device 1A of Fig. 2, when the output of the pump 3 and the sizes of the gas-liquid separation tank 5 and the electrolyte solution storage tank 2 are the same as those of the electrolytic device 1 of Fig. 1, the flow rate of the electrolyte solution in the gas-liquid separation tank 5 and the electrolyte solution storage tank 2 can be reduced, thereby extending the residence time of the electrolyte solution in the gas-liquid separation tank 5 and the electrolyte solution storage tank 2. Therefore, the electrolytic device 1A has good gas-liquid separation efficiency.

[0027] As shown in FIG. 3, the circulation flow path 6B of the electrolysis device 1B includes a pipe 62 (second pipe) for sending the electrolyte solution discharged from the pump 3 to the electrolysis cell 4, a pipe 63 (third pipe) for sending the electrolyte solution from the electrolysis cell 4 to the gas-liquid separation cell 5, a pipe 64 for sending the electrolyte solution from the gas-liquid separation cell 5 to the electrolyte solution storage tank 2, and a pipe 61 for sending the electrolyte solution from the electrolyte solution storage tank 2 to the pump 3, as in the electrolysis device 1 of FIG. 1, and further includes a pipe 67 (fourth pipe) branched from the pipe 62 (second pipe), bypassing the electrolysis cell 4 and joining the pipe 63 (third pipe). The flow rate of the electrolyte solution in the pipe 67 bypassing the electrolysis cell 4 is greater than the flow rate of the electrolyte solution to the electrolysis cell 4 through the pipe 62. With the above configuration, the electrolyte solution forced into the electrolysis cell 4 by the pump 3 can be discharged from the discharge port of the electrolysis cell 4 to the pipe 63 as the electrolyte solution, and can be joined with the electrolyte solution from the pipe 67 that bypasses the electrolysis cell 4. Therefore, the suction pressure by the pump 3 can be distributed to the electrolytic cell 4 and the pipe 67, and the inflow pressure to the electrolytic cell 4 can be adjusted. Other configurations of the electrolytic device 1B are similar to those of the electrolytic device 1, and the electrolytic device 1B can achieve the same effects as the electrolytic device 1.

[0028] The present invention can be implemented in the embodiments without departing from its features. The embodiments, modifications, and effects are merely illustrative and should not be construed as limiting the present invention. The features and structures of the embodiments and modifications can be added and combined in various ways to obtain alternative configurations. [Explanation of symbols]

[0029] 1, 1A, 1B...electrolysis device, 2...electrolyte solution storage tank, 3...pump, 4...electrolytic cell, 5...gas-liquid separation cell, 21...supply port, 52...outlet.

Claims

1. an electrolytic cell that electrolyzes an electrolyte solution to generate an electrolyte solution containing a gas; a gas-liquid separation tank for separating gas from the electrolytic solution sent from the electrolytic tank to produce an electrolytic solution; an electrolyte solution storage tank for storing the electrolyte solution sent from the gas-liquid separation tank; a pump that draws the electrolyte solution from the electrolyte solution storage tank and sends it to the electrolytic cell; the gas-liquid separation tank has an outlet through which the electrolyte solution flows into the electrolyte solution storage tank; an electrolysis apparatus, wherein the electrolyte solution storage tank has a supply port at a position higher than the outlet, for supplying the electrolyte solution from the gas-liquid separation tank into the electrolyte solution storage tank;

2. 2. The electrolysis apparatus according to claim 1, an electrolysis apparatus comprising a crank-shaped first pipe connecting the gas-liquid separation tank and the electrolyte solution storage tank, the first pipe being connected to the outlet and the supply port.

3. 2. The electrolysis apparatus according to claim 1, a second pipe for sending the electrolyte solution discharged from the pump to the electrolytic cell; a third pipe for conveying an electrolytic solution from the electrolytic cell to the gas-liquid separation cell; a fourth pipe branching off from the second pipe, bypassing the electrolytic cell, and joining the third pipe.

4. In the electrolysis apparatus according to any one of claims 1 to 3, The electrolyte solution storage tank is an electrolysis device that discharges gas separated from the stored electrolyte solution to the outside.

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