TW201631221A - Electrolysis system - Google Patents

Abstract

An electrolysis system 1 includes an electrolysis vessel 6 in which an electrode formed of an anode and a cathode is accommodated, an electrolysis device 2 which electrolyzes a liquid to be treated, a control vessel 3 which temporally retains the liquid to be treated which is treated by the electrolysis device 2, a recycle line 10 which recovers part of a retained liquid R which is retained in the control vessel 3 and includes fine particles and a deposition substance formed of deposited fine particles to the electrolysis vessel 6, and a prevention device 18 which prevents deposition of the deposition substance in the control vessel 3.

Description

Electrolysis system

The present invention relates to an electrolysis system including an electrolysis device that electrolyzes a liquid to be treated such as seawater.

The present application claims priority to Japanese Patent Application No. 2015-028499, filed on Feb. 17, 2015, the content of which is incorporated herein.

In the past, in the thermal power plants, nuclear power plants, seawater desalination plants, chemical plants, etc., where seawater is used in large quantities, algae or shellfish are attached to the seawater contact parts such as water intakes, pipes, rehydrators, and various coolers. Breeding has become a problem.

In order to solve this problem, an electrolytic system for producing sodium hypochlorite (chlorine, sodium hypochlorite) by electrolysis of natural seawater has been proposed. In this system, an electrolyte containing sodium hypochlorite is injected into a water intake port, thereby suppressing adhesion of marine organisms (for example, refer to Patent Document 1). In general, in this system, scale components such as magnesium ions in seawater generate scale.

Patent Document 1 describes that in order to prevent the accompanying electrolysis In the case where scale is attached to the electrode of the electrolysis device, a device that supplies air to the liquid to be treated is used. In this device, the flow rate of the electrode surface is increased and turbulent due to the air blown into the liquid to be treated, thereby improving the cleaning effect of the electrode.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 4932529

However, in the system in which the liquid to be treated discharged from the electrolysis device is circulated in the adjustment tank (circulation tank), there is scale on the bottom of the electrolysis cell (electrode surface) where electrolysis is performed and the adjustment tank in which the liquid to be treated is temporarily stored. The problem of precipitation.

The removal of the scale to be precipitated requires a large-scale project such as an acid washing process, and there is a problem that the operating cost of the electrolysis system increases.

It is an object of the present invention to provide an electrolysis system which prevents precipitation of precipitated matter (scale) at the bottom of the adjustment tank.

An electrolysis system according to a first aspect of the present invention is characterized by comprising: The electrolysis device has an electrolytic cell that houses an anode and a cathode as electrodes, and electrolyzes the liquid to be treated; the tank is adjusted to temporarily store the liquid to be treated treated by the electrolyzer; and the circulation line is stored in the conditioning tank. A part of the storage liquid containing the fine particles and the precipitated material precipitated from the fine particles is returned to the electrolytic cell; and a means for preventing the precipitation of the precipitated substance in the adjustment groove.

With this configuration, by the means of prevention, it is possible to prevent precipitation of the precipitated substance at the bottom of the adjustment tank.

Further, the retentate is returned to the electrolysis cell, whereby the fine particles contained in the retentate are separated together with the precipitated substance formed on the electrode surface. Thereby, accumulation of the precipitated substance on the electrode surface can be prevented. In other words, the fine particles contained in the retentate returned to the electrolytic cell function as a seed crystal, thereby suppressing the growth of the precipitated material on the electrode surface.

In addition, the pH of the electrolytic solution to be treated is increased, and precipitated substances such as calcium carbonate or magnesium hydroxide which are precipitated are separated from the electrode surface and precipitated on the surface of the fine particles (seed crystals) floating in the liquid, thereby preventing the precipitation. Precipitation of precipitated material on the cathode surface.

In the above electrolysis system, the prevention means may have a discharge pipe that discharges liquid to the adjustment tank.

With this configuration, the liquid is injected by the discharge pipe, whereby the retentate in the adjustment tank is stirred. Thereby, the bottom of the adjustment preventing groove can be raised The effect of precipitating the precipitated material.

In the above electrolysis system, the discharge pipe can be discharged in a direction in which the retentate stored in the adjustment tank generates a swirling flow.

With this configuration, the precipitated substance contained in the retentate is stably stirred, whereby the effect of preventing precipitation of the precipitated substance at the bottom of the adjustment tank can be enhanced.

In the above-described electrolysis system, the preventing means may include a wall member extending in a vertical direction of the adjustment groove, and dividing the inside of the adjustment groove into an ascending portion and a descending portion; and supplying air to a lower portion of the rising portion Air agitation device of the air supply unit.

With this configuration, the agitation/dispersion effect of the retentate can be obtained by the aeration power of the air. Thereby, the effect of preventing precipitation of the precipitated substance at the bottom of the adjustment tank can be enhanced.

In the above electrolysis system, the prevention means may be a mechanical stirring device that mechanically agitates the retentate in the adjustment tank.

With this configuration, the retentate is forcibly stirred. Thereby, the effect of preventing precipitation of the precipitated substance at the bottom of the adjustment tank can be enhanced.

In the above electrolysis system, the anode may be coated with titanium as a coating material containing cerium oxide.

With this configuration, even if the ruthenium-containing coating material in which the manganese scale adheres easily during electrolysis is coated with titanium, the precipitated substance can be prevented from growing on the electrode surface.

In the above electrolysis system, it is possible to have: The injection line supplies a part of the electrolytic solution to a predetermined place from the circulation line; the seawater supply line supplies seawater to the adjustment tank; and the branch line divides a part of the seawater of the seawater supply line into the injection line.

With this configuration, the flow rate of the injection line can be increased by injecting seawater through the branch line. Thereby, when the distance of the injection line is long and the precipitated substance is easily precipitated, the flow rate of the injection line can be prevented from being lowered to cause deposition of the precipitated substance.

By virtue of the present invention, precipitation of precipitated substances at the bottom of the adjustment tank can be prevented.

1, 1B, 1C, 1D‧‧‧ electrolysis system

2‧‧‧Electrolytic device

3‧‧‧Adjustment slot

3a‧‧‧ outer perimeter

3b‧‧‧ bottom

4‧‧‧Seawater supply pipeline

5‧‧‧Seawater supply pump

6‧‧‧electrolyzer

7‧‧‧DC power supply unit

10‧‧‧Circular pipeline

11‧‧‧First circulation pipeline

12‧‧‧Second circulation pipeline

13‧‧‧Injection pipeline

15‧‧‧Inlet

16‧‧‧Exit

17‧‧‧Injection pump

18‧‧‧Spit tube (precaution means)

20‧‧‧Mechanical stirring device (preventing means)

22‧‧‧propeller

24‧‧‧columnar structures

26‧‧‧electrode support box

30‧‧‧Electrode

31‧‧‧2-pole electrode plate

32‧‧‧Anode plate

33‧‧‧ cathode plate

34‧‧‧Air agitator (precaution means)

35‧‧‧Air Supply Department

36‧‧‧Wall members

37‧‧‧Nozzles

38‧‧‧Rising Department

39‧‧‧Down

41‧‧‧Differential pipeline

42‧‧‧Seawater divergent flow regulating valve

A‧‧‧Anode

E‧‧‧ electrolyte

K‧‧‧ cathode

M‧‧‧electrode group

R‧‧‧Reservoir

W‧‧‧Seawater

Fig. 1 is a schematic view showing an outline of an electrolysis system according to a first embodiment of the present invention.

Fig. 2 is a longitudinal cross-sectional view showing an outline of an electrolytic cell constituting an electrolysis device according to a first embodiment of the present invention.

Fig. 3 is a schematic view of the adjustment groove of the first embodiment of the present invention as viewed from above.

Fig. 4 is a schematic view showing an outline of an electrolysis system according to a second embodiment of the present invention.

Fig. 5 is a schematic view showing an outline of an electrolysis system according to a third embodiment of the present invention.

Fig. 6 is a schematic view showing an outline of an electrolysis system according to a fourth embodiment of the present invention.

Fig. 7 is a perspective view of an adjustment groove of an electrolysis system according to a fifth embodiment of the present invention.

(first embodiment)

Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.

Fig. 1 is a schematic view showing an outline of an electrolysis system 1 of the present embodiment. The electrolysis system 1 of the present embodiment is a system that electrolyzes a liquid to be treated such as seawater W to produce an electrolytic solution E containing sodium hypochlorite (chlorine or sodium hypochlorite).

The electrolysis system 1 of the present embodiment is a piping for cooling equipment of a plant including a sodium hypochlorite through an injection line 13, for example, a fire power and a nuclear power plant; a seawater desalination plant; a chemical plant; a steel plant. It is supplied at a predetermined place such as a nitrogen treatment tank that stores nitrogen-containing drainage.

The electrolysis system 1 includes a seawater supply pump 5 that introduces seawater W required for electrolysis, and an adjustment tank 3 that temporarily stores the electrolytic solution E (seawater W) treated by the electrolysis device 2; the electrolysis device 2; a circulating cycle line 10 of liquid E circulation; will be circulated in the circulation line 10 The electrolytic solution E is injected into the injection line 13 of the piping of the factory, for example.

The circulation line 10 is composed of a first circulation line 11 and a second circulation line 12.

The adjustment tank 3 is a bottomed cylindrical groove, and stores the electrolytic solution E circulating in the system and the seawater W supplied from the seawater supply pump 5. The adjustment tank 3 has a fan (not shown) that supplies air to the gas phase of the adjustment tank 3. The shape of the adjustment groove 3 is not limited to a cylindrical shape having a bottom, and may be formed into a rectangular parallelepiped shape.

The electrolysis device 2 is a device that electrolyzes the seawater W in the middle of the circulation line 10. The electrolysis device 2 has an electrolytic cell 6 and a DC power supply device 7 (rectifier). The electrolysis device 2 is a device that generates sodium hypochlorite by electrolyzing seawater W.

As shown in FIG. 2, the electrolytic cell 6 is composed of an electrode support box 26, a terminal block 28, and a plurality of electrodes 30. The electrolytic cell 6 houses the anode A and the cathode K as the electrode 30. The electrolytic cell 6 has an inflow port 15 into which the electrolytic solution E is introduced into the inside of the electrolytic cell 6, and an outflow port 16 through which the electrolytic solution E is discharged from the inside of the electrolytic cell 6.

The terminal block 28 has a function of supplying an electric current from the outside of the electrolytic cell 6 to the electrode 30 supported in the electrode support case 26. Terminal plates 28 are disposed one at each end of the electrode support box 26.

The electrode 30 is formed in a plate shape and is fixedly supported by the support rod 26a of the electrode support case 26 in a plurality of array states. In the present embodiment, as the electrode 30, three types of the electrode plate 31, the anode plate 32, and the cathode plate 33 are used.

The two-electrode electrode plate 31 has a structure in which a titanium substrate as an electrode substrate is divided into two parts, one of which serves as an anode A and the other of which serves as a cathode K. In other words, the region of the one end side of the two-electrode electrode plate 31 is an anode A which is coated with a coating material containing cerium oxide (a coating material mainly composed of cerium oxide), and a half of the other end side. Then, it is a cathode K in which the coating material mainly composed of the above cerium oxide is not covered on the surface.

The anode plate 32 has a structure in which the covering material mainly composed of cerium oxide is coated on the entire surface of the titanium substrate. The entire anode plate 32 functions as the anode A at the time of electrolysis. As the cathode plate 33, a titanium substrate which is not coated is used. The entire cathode plate 33 functions as a cathode K at the time of electrolysis.

Here, the arrangement structure of the three types of electrodes 30 in the electrode support case 26 will be described. The two-electrode electrode plate 31, the anode plate 32, and the cathode plate 33 are each fixedly supported on a support rod 26a in the electrode support box 26.

As shown in Fig. 2, the plurality of two-electrode plates 31 in the electrode 30 are arranged such that the anode A faces the liquid inlet side and the cathode K faces the liquid outlet side. The plurality of two-electrode plates 31 are arranged such that the direction in which the two-electrode plates 31 extend in the direction in which the seawater W flows. The plurality of electrode plates 31 are arranged in a line in the flow direction of the seawater W, thereby constituting the electrode group M. The electrode group M is provided in plural plural intervals so as to be parallel to each other. The plurality of electrode groups M are arranged side by side.

The DC power supply device 7 is a current for electrolysis of seawater W A device that supplies. As the DC power supply device 7, for example, a configuration in which a DC power supply and a constant current control circuit are provided can be employed. The DC power source is a power source that outputs DC power. For example, the AC power output from the AC power source is rectified to DC and output.

The seawater supply pump 5 and the adjustment tank 3 are connected by the seawater supply line 4. In the seawater supply line 4, a filter for preventing foreign matter from entering the electrolyte may be provided.

The adjustment tank 3 and the inflow port 15 of the electrolytic cell 6 are connected by the first circulation line 11. That is, a part of the electrolytic solution E (reservoir R) in the adjustment tank 3 is introduced into the electrolytic cell 6 via the first circulation line 11. An injection pump 17 is provided on the first circulation line 11. The injection pump 17 is a pump that supplies the circulating electrolytic solution E to the adjustment tank 3 and transfers the electrolytic solution E to the injection line 13.

The second circulation line 12 is a line that connects the outflow port 16 of the electrolytic cell 6 and the adjustment tank 3. That is, the electrolytic solution E generated by the electrolysis device 2 is introduced into the adjustment tank 3 via the second circulation line 12.

An injection nozzle (not shown) is provided at the downstream end of the injection line 13. By providing the injection nozzle, the sodium hypochlorite produced by the electrolysis device 2 can be efficiently diffused into the piping of the factory.

The connection portion between the second circulation line 12 and the adjustment tank 3 of the present embodiment is provided with a discharge pipe 18 for discharging the electrolytic solution E into the adjustment tank 3. In other words, the electrolytic solution E that has been circulated in the circulation line 10 and supplied to the adjustment tank 3 is discharged through the discharge pipe 18 to the retentate R stored in the adjustment tank 3.

The discharge pipe 18 is a tubular member and is disposed such that the retentate R in the adjustment tank 3 generates a swirling flow. As shown in FIG. 3, the discharge pipe 18 determines the direction so that the electrolytic solution E discharged from the upper side is discharged along the outer peripheral surface 3a of the adjustment groove 3. In other words, the extending direction of the discharge pipe 18 is arranged in a tangential direction along the tangential direction of the outer peripheral surface 3a of the adjustment groove 3.

Next, the action of the electrolysis system 1 of the present embodiment will be described.

First, the seawater W is introduced into the adjustment tank 3 via the seawater supply line 4. The seawater W is introduced into the first circulation line 11, the electrolytic cell 6, and the second circulation line 12, and is circulated. In this process, the seawater W is returned to the electrolytic cell 6 via the first circulation line 11. Thereby, the electrode 30 (the cathode K and the anode A) in the electrolytic cell 6 is immersed in the seawater W.

Further, the electrolytic solution E circulated from the second circulation line 12 is discharged into the reserving liquid R in the adjustment tank 3 via the discharge pipe 18.

The seawater W is electrolyzed by flowing an electric current in the seawater W between the electrodes 30.

That is, in the anode A, as shown in the following formula (1), the chloride ions in the seawater W are oxidized by the electron e, and chlorine is generated.

2Cl ^- →Cl ₂ +2e ^- ...(1)

On the other hand, in the cathode K, as shown in the following formula (2), water in the seawater W is reduced by electrons, and further, hydroxylated ions and hydrogen gas are generated.

2H ₂ O+2e ^- →2OH ^- +H ₂ ...(2)

Further, as shown in the following formula (3), the hydroxyl group formed at the cathode K The ions react with sodium ions in seawater W to form sodium hydroxide.

2Na ⁺ +2OH ^- → 2NaOH...(3)

Further, as shown in the formula (4), sodium hypochlorite, sodium chloride and water are produced by reacting sodium hydroxide and chlorine.

Cl ₂ +2NaOH→NaClO+NaCl+H ₂ O...(4)

As described above, by the electrolysis of the seawater W, sodium hypochlorite having an inhibitory effect on the adhesion of marine products is generated.

The concentration of sodium hypochlorite is preferably 500 to 5,000 ppm because the chloride ion concentration of seawater W is increased to 30,000 to 40,000 mg/l.

Here, in general, the seawater W or the electrolytic solution E returned to the electrolytic cell 6 contains scale components (fine particles, fine particles of precipitated scales, and fine particles that function as seed crystals for depositing scale), for example, magnesium. Ions (Mg ²⁺ ), calcium ions (Ca ²⁺ ), manganese ions (Mn ²⁺ ), and _{citric acid} ([SiO _X (OH) _4-2X ] _n ).

In addition, in the anode A of the coating material which is coated with the cerium oxide, the manganese scale derived from the precipitated substance of the manganese ions contained in the seawater W adheres during the electrolysis. Since the adhesion of the manganese scale causes the consumption of the anode A, further, since the catalytic activity on the surface of the electrode 30 is lowered, the chlorine generation efficiency is lowered. At the cathode K, scale derived from magnesium or calcium contained in the seawater W adheres, and the consumption of the electrode 30 is still generated due to scale.

In the electrolysis system 1 of the present embodiment, the electrolytic solution E circulated from the second circulation line 12 is produced in the retentate R by the discharge pipe 18. Produce a swirling flow. Thereby, precipitation of the scale contained in the electrolytic solution E and the storage liquid R is prevented. That is, the discharge pipe 18 functions as a means for preventing scale deposition.

In the electrolysis system 1 of the present embodiment, the scale component or scale contained in the electrolytic solution E is detached by the scale generated on the surface of the electrode 30. In other words, the scale fine particles contained in the inflowing electrolytic solution E function as a seed crystal to remove the scale on the surface of the electrode 30. Thereby, scale accumulation on the surface of the counter electrode 30 is suppressed.

In addition, with the electrolysis, the pH (hydrogen ion index) of the electrolytic solution E rises and becomes highly alkaline, whereby the scale component is precipitated as scales such as calcium hydroxide or magnesium hydroxide.

In the electrolysis system 1 of the present embodiment, the electrolytic solution E containing the scale component is returned to the electrolytic cell 6, whereby scale such as calcium carbonate or magnesium hydroxide is released from the electrode 30 and precipitates on the surface of the scale component floating in the liquid. . Thereby, precipitation of scale on the cathode K surface can be prevented.

The seawater W after the electrolysis is discharged as the electrolytic solution E from the outlet 16 of the electrolytic cell 6 together with the hydrogen gas, and is stored in the adjustment tank 3 via the second circulation line 12. In the adjustment tank 3, hydrogen gas generated by the electrolytic reaction is stored on the gas phase side. The hydrogen gas is diluted to below the burst limit by the air supplied to the gas phase, and then discharged.

The retentate R containing the electrolytic solution E stored in the adjustment tank 3 is introduced into the injection line 13 by the injection pump 17, and then injected into a predetermined place such as a pipe of the cooling device. That is, the electrolytic solution E containing sodium hypochlorite is injected into the predetermined place via the injection line 13 by the operation of the injection pump 17.

By the above-described embodiment, the electrolyte solution E containing sodium hypochlorite is injected into a predetermined place such as a pipe of the cooling device via the injection line 13, whereby the adhesion of marine organisms can be effectively suppressed.

Further, the nitrogen component contained in the nitrogen-containing drain discharged from the factory can be removed via the injection line 13. That is, the nitrogen component contained in the drainage can be removed by injecting the electrolytic solution E containing sodium hypochlorite into the nitrogen treatment tank for storing the nitrogen-containing drainage.

Further, the electrolytic solution E is discharged to the adjustment tank 3 via the discharge pipe 18, and the retentate R in the adjustment tank 3 generates a swirling flow. Thereby, it is possible to prevent the scale from being deposited on the bottom of the adjustment tank 3. That is, the scale is continuously floated in the retentate R by swirling the scale. As a result, the scale is less likely to accumulate at the bottom of the adjustment tank 3, and the burden of the scale removal work is reduced, and the maintainability can be improved.

Further, the retentate R is returned to the electrolytic cell 6, and the scale component contained in the reserving liquid R is released by the scale generated on the surface of the electrode 30. Thereby, accumulation of scale on the surface of the electrode 30 can be prevented. In other words, the scale fine particles contained in the reserving liquid R returned to the electrolytic cell 6 function as a seed crystal, whereby the deterioration of the electrode can be alleviated.

Further, by preventing scale accumulation on the surface of the counter electrode 30, it is possible to suppress an increase in the electrolysis voltage (deterioration of the power consumption rate).

In addition, the short circuit of the electrodes 30 can be prevented from causing spark generation, and safety can be improved.

In addition, scales such as calcium carbonate or magnesium hydroxide precipitated by the increase in pH of the electrolytic solution E are separated from the surface of the electrode 30. The surface of scale microparticles (seed crystals) floating in the liquid is precipitated, and scale deposition on the cathode surface can be prevented.

In addition, the anode A which is formed by coating the coating material containing cerium oxide which is easily adhered to the manganese scale during electrolysis can suppress the growth of scale on the surface of the electrode 30.

Further, the fouling substance (NH ₃ , COD, or the like) contained in the seawater W is oxidatively decomposed by sodium hypochlorite, and the electrode caused by the oxidation of the electrode 30 (anode A) by the fouling substance can be prevented from deteriorating.

Further, in the above embodiment, the configuration in which the electrolytic solution E is discharged by the discharge pipe 18 is employed, but the invention is not limited thereto. For example, the seawater W supplied through the seawater supply pump 5 may be discharged by the discharge pipe 18. In other words, the retentate R stored in the adjustment tank 3 may be caused to generate a swirling flow.

(Second embodiment)

Hereinafter, an electrolysis system 1B according to a second embodiment of the present invention will be described based on the drawings. In the present embodiment, the differences from the above-described first embodiment will be mainly described, and the description of the same portions will be omitted.

As shown in FIG. 4, in the adjustment tank 3 of the electrolysis system 1B of this embodiment, as a discharge pipe 18 of the first embodiment, a machine for mechanically agitating the retentate R in the adjustment tank 3 is provided. Stirring device 20. The mechanical stirring device 20 is similar to the discharge pipe 18 in preventing precipitation of scale.

The mechanical stirring device 20 includes a motor 21 having an output shaft and a propeller 22 provided on an output shaft of the motor 21.

By starting the mechanical stirring device 20, the retentate R stored in the adjustment tank 3 is forcibly stirred. In other words, the scale component (fine particles) or scale contained in the electrolytic solution E stored in the adjustment tank 3 rides on the flow formed by the mechanical stirring device 20 without precipitation.

With the above embodiment, the retentate R stored in the adjustment tank 3 is forcibly stirred by using the mechanical stirring device 20. Thereby, it is possible to prevent the scale from being deposited on the bottom of the adjustment tank 3.

(third embodiment)

Hereinafter, an electrolysis system 1C according to a third embodiment of the present invention will be described based on the drawings.

As shown in Fig. 5, in the adjusting tank 3 of the electrolytic system 1C of the present embodiment, an air stirring device 34 is provided instead of the discharge pipe 18 of the first embodiment. The air agitating device 34 has a wall member 36 located in the adjustment tank 3 and an air supply unit 35 that supplies air to the retentate R.

The wall member 36 is a plate-like member that extends in the vertical direction of the adjustment groove 3 and divides the inside of the adjustment groove 3. The wall member 36 is formed to have a predetermined gap between the lower end of the wall member 36 and the bottom of the adjustment groove 3, and between the upper end of the wall member 36 and the liquid surface of the retentate R.

The air supply unit 35 is a pair that is distinguished by the wall member 36. The lower part of the space is supplied with air. The air supply unit 35 includes a blower (not shown) that pressurizes air to be pressurized air, and a nozzle 37 that supplies pressurized air to the retentate R.

The nozzle 37 supplies air to a lower portion of one of the storage liquids R that is distinguished by the wall member 36. The pressurized air is supplied through the nozzle 37, and the one space becomes the rising portion 38 where the air rises from the bottom. The pressurized air will rise and detach from the top to the outside. Therefore, there is almost no air in the other space (falling portion 39). The retentate R in the tank 3 is adjusted by the difference in density of the retentate R of the rising portion 38 and the descending portion 39, and circulates between the rising portion 38 and the descending portion 39.

With the above embodiment, the agitation/dispersion effect of the retentate R can be obtained by the aeration power of the air.

In addition, by using air to increase the concentration of dissolved oxygen (Dissolved Oxygen, DO), manganese ions, tannic acid, and oxidation to manganese dioxide (MnO ₂ ) and cerium oxide (SiO ₂ ) can be prevented to prevent scale components. Scale is deposited on the surface of the electrode 30 (anode A).

Further, aeration performed by air is performed to increase the concentration of dissolved carbon dioxide (CO ₃ ²⁺ ) in the electrolytic solution E (for example, pH 8.5), and promote the reaction of calcium ions as precipitation of calcium carbonate, thereby preventing the scale component from being on the electrode 30 ( Scale is deposited on the surface of the cathode K).

(Fourth embodiment)

Hereinafter, an electrolysis system 1D according to a fourth embodiment of the present invention will be described based on the drawings.

As shown in Fig. 6, between the seawater supply line 4 of the electrolysis system 1D of the present embodiment and the injection line 13, a branch line for directly introducing the seawater W supplied from the seawater supply pump 5 into the injection line 13 is provided. 41 (alternate pipeline). That is, in the electrolysis system 1 of the present embodiment, the seawater W flowing through the seawater supply line 4 can be sent to the adjustment tank 3 without being directly branched into the injection line 13.

The branch line 41 is provided with a seawater branch flow rate adjustment valve 42 for adjusting the flow rate of the seawater W flowing through the branch line 41.

With the above embodiment, the flow rate of the injection line 13 can be increased by injecting the seawater W through the branch line 41. Thereby, even when the distance of the injection line 13 is long and the pH of the electrolytic solution is likely to change and the scale is deposited, the precipitation of scale can be suppressed. That is, scale accumulation due to a decrease in the flow rate of the injection line 13 can be prevented.

The flow rate of the seawater W injected through the branch line 41 can be appropriately adjusted by operating the seawater branch flow rate adjusting valve 42.

(Fifth embodiment)

Hereinafter, an electrolysis system according to a fifth embodiment of the present invention will be described based on the drawings. In the present embodiment, the differences from the above-described first embodiment will be mainly described, and the description of the same portions will be omitted.

As shown in FIG. 7, the center portion of the adjustment groove 3 of the present embodiment viewed from above is provided with a columnar columnar structure 24 extending in the vertical direction. The columnar structure 24 is an adjustment groove having a cylindrical shape with a bottom The central axis of 3 is arranged to be substantially coaxial. The vicinity of the center of the swirling flow of the reserving liquid R formed by the discharge pipe 18 is formed.

According to the above embodiment, it is possible to suppress the formation of the scale block at the center portion of the bottom portion 3b of the adjustment groove 3.

Further, in the electrolysis system of the present embodiment, the columnar structure 24 for forming the scale block at the center portion of the bottom portion 3b of the adjustment groove 3 is provided, but the invention is not limited thereto. For example, a convex portion that is convex upward is formed in the central portion of the bottom portion 3b of the adjustment groove 3, and the formation of the scale block may be suppressed.

The shape of the columnar structure 24 is not limited to a cylindrical shape, and may be formed into a prismatic shape. Further, it is not necessary to be solid, and a cylindrical shape having a hollow portion inside may be used.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, and the invention may be modified, omitted, substituted, and other modifications without departing from the spirit and scope of the invention. Further, the present invention is not limited by the embodiment, but is limited only by the scope of the patent application.

1‧‧‧Electrolysis system

2‧‧‧Electrolytic device

3‧‧‧Adjustment slot

4‧‧‧Seawater supply pipeline

5‧‧‧Seawater supply pump

6‧‧‧electrolyzer

7‧‧‧DC power supply unit

10‧‧‧Circular pipeline

11‧‧‧First circulation pipeline

12‧‧‧Second circulation pipeline

13‧‧‧Injection pipeline

15‧‧‧Inlet

16‧‧‧Exit

17‧‧‧Injection pump

18‧‧‧Spit tube (precaution means)

E‧‧‧ electrolyte

R‧‧‧Reservoir

W‧‧‧Seawater

Claims (7)

An electrolysis system comprising: an electrolysis device having an electrolytic cell in which an anode and a cathode as electrodes are housed, electrolyzing the liquid to be treated; adjusting a tank to temporarily store a liquid to be treated treated by the electrolysis device; and a circulation line; A part of the storage liquid containing the fine particles and the precipitated material deposited by the fine particles stored in the adjustment tank is returned to the electrolytic cell, and a means for preventing precipitation of the precipitated substance in the adjustment tank. The electrolysis system according to claim 1, wherein the prevention means has a discharge pipe that discharges the liquid to the adjustment tank. The electrolysis system according to claim 2, wherein the discharge pipe discharges in a direction in which a swirling flow is generated in the storage liquid stored in the adjustment tank. The electrolysis system according to claim 1, wherein the preventing means includes: a wall member extending in a vertical direction of the adjustment groove, and dividing the inside of the adjustment groove into an ascending portion and a descending portion; and An air stirring device that supplies the air supply portion of the air to the lower portion of the rising portion. The electrolysis system according to claim 1, wherein the preventing means is a mechanical stirring device that mechanically agitates the retentate in the adjustment tank. The electrolysis system according to any one of claims 1 to 5, wherein the anode is made by coating a coating material containing cerium oxide with titanium. The electrolysis system according to any one of claims 1 to 6, comprising: an injection line for supplying a part of the electrolytic solution to a predetermined place from the circulation line; and a seawater supply line for supplying seawater to the adjustment tank; In the pipeline, a part of seawater of the seawater supply line is branched and introduced into the injection line.