JP2016002509A - Electrolytic water generation system and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrolytic water generation system and method that can suppress variation of pH.SOLUTION: An electrolytic water generation system according to the present invention comprises: an electrolytic cell that has an anode and a cathode and is provided with a diaphragm between the anode and the cathode; a supply pipe that supplies an electrolyte containing hydrochloric acid to the electrolytic cell; a discharge pipe that discharges an electrolysis product, produced by electrolytic treatment in the electrolytic cell, from the electrolytic cell; a mixing part that mixes the electrolysis product discharged from the discharge pipe with water to be treated to produce acidic electrolytic water; and a storage tank that stores the acidic electrolytic water discharged from the mixing part and continuously discharges the acidic electrolytic water. When the flow rate of the acidic electrolytic water discharged from the mixing part is S (L/s) and the discharge cycle of the electrolysis product discharged from the electrolytic cell to the discharge pipe is t (s), the volume of the storage tank is S×t (L) or more.

Description

  The present invention relates to an electrolyzed water generation system and an electrolyzed water generation method.

  In recent years, various methods for generating electrolyzed water have been proposed for the purpose of sterilization from the viewpoint of hygiene. For example, Patent Document 1 proposes a device that supplies electrolytic water containing hydrochloric acid to an electrolytic cell in which a cathode and an anode are housed, and generates acidic electrolytic water by electrolytic treatment. This apparatus employs a so-called single-chamber electrolytic cell that does not have a partition wall between an anode and a cathode, and hydrochloric acid, chlorine, and the like are discharged as electrolytic products. In addition to using the electrolytic treatment solution directly as sterilizing water as in Patent Document 1, a method of generating electrolytic water by mixing electrolytic products discharged from an electrolytic cell with tap water or the like has also been proposed. .

JP-A-10-128336

  However, as described above, the system has the following problems. That is, the electrolytic product is not always discharged from the electrolytic cell as described above, and the electrolytic product is discharged according to the supply cycle of the electrolytic solution such as hydrochloric acid supplied to the electrolytic cell. Therefore, since the electrolytic product is periodically mixed with tap water, there is a problem that the pH of the generated electrolytic water varies and it is difficult to obtain electrolytic water having a desired pH.

  The present invention has been made to solve the above problems, and an object thereof is to provide an electrolyzed water generation system and an electrolyzed water generation method capable of suppressing variations in pH.

  An electrolyzed water generating system according to the present invention has an anode and a cathode, and an electrolytic cell in which no diaphragm is provided between the anode and the cathode, and a supply pipe for supplying an electrolytic solution containing hydrochloric acid to the electrolytic cell The electrolytic product generated by the electrolytic treatment in the electrolytic bath is mixed with the discharge pipe for discharging the electrolytic product from the electrolytic bath and the electrolytic product discharged from the discharge pipe into the water to be treated to generate acidic electrolytic water. A mixing tank; and a storage tank that continuously discharges the acidic electrolyzed water discharged from the mixing section, and the flow rate of the acidic electrolyzed water discharged from the mixing section is S (L / sec). ), When the discharge cycle of the electrolytic product discharged from the electrolytic cell to the discharge pipe is t (seconds), the volume of the storage tank is S × t (L) or more.

  Since the electrolytic product is discharged from the electrolytic cell at a predetermined cycle, when this is mixed with the water to be treated in the mixing unit, the pH of the generated acidic electrolytic water varies depending on the timing of discharging from the mixing unit. It will be. That is, the acidic electrolyzed water immediately after mixing the electrolysis product and the acidic electrolyzed water just before the electrolysis product is mixed next have a different pH. Therefore, in the present invention, the acidic electrolyzed water discharged from the mixing unit is stored, and a storage tank for continuously discharging is provided, and the flow rate of the acidic electrolyzed water discharged from the mixing unit is S (L / sec), When the discharge cycle of the electrolytic product discharged from the electrolytic cell to the discharge pipe is t (seconds), the volume of the storage tank is set to S × t (L) or more. Thereby, for example, since the acidic electrolyzed water from when the electrolytic product is mixed with the water to be treated to the next electrolytic product is once stored in the storage tank and discharged, In the storage tank, acidic electrolyzed water in which the injection amount of the electrolytic product is averaged is generated. Therefore, the dispersion | variation in pH of the electrolytic product discharged | emitted from a storage tank can be suppressed.

  In the said electrolyzed water production | generation system, it is preferable that the volume of the said storage tank shall be 2xSxt (L) or more. Thereby, the dispersion | variation in pH is further suppressed.

  Moreover, in the said electrolyzed water production | generation system, the stirring tank which stirs the said acidic electrolyzed water accommodated in the said storage tank can be provided. Thereby, the dispersion | variation in pH can be suppressed further reliably.

  The method for producing electrolyzed water according to the present invention comprises a step of supplying an electrolytic solution containing hydrochloric acid to an electrolytic cell having an anode and a cathode, and a partition wall is not provided between the anode and the cathode, and the electrolytic cell The electrolytic treatment to produce an electrolytic product, the step of discharging the electrolytic product from the electrolytic cell every t (seconds), the electrolytic product is mixed with the water to be treated, and the acidic electrolysis While producing | generating water and discharging the said acidic electrolyzed water by the flow volume of S (L / sec), while storing the said acidic electrolyzed water in the storage tank whose volume is more than Sxt (L), it is continuous. And a step of discharging.

  According to the present invention, variation in pH can be suppressed.

It is a schematic block diagram of the electrolyzed water production | generation system which concerns on one Embodiment of this invention. It is an exploded view of the electrolytic cell of FIG. It is sectional drawing of the electrolytic cell of FIG. It is a schematic block diagram which shows the other example of the storage tank of the electrolyzed water production | generation system of FIG.

<1. Overview of electrolyzed water generation system>
Hereinafter, an embodiment of an electrolyzed water generation system according to the present invention will be described with reference to the drawings.

  First, a schematic configuration of this electrolyzed water generation system will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of the electrolyzed water generation system. As shown in the figure, this system includes an electrolytic cell 1 including electrodes. An electrolytic solution containing hydrochloric acid is supplied to the electrolytic cell 1 through a supply pipe 2, and an electrolytic product containing hydrochloric acid, chlorine, and hydrogen is generated by subjecting the electrolytic solution to electrolytic treatment in the electrolytic cell 1. . The electrolytic product is discharged to the outside through the first discharge pipe 3 connected to the electrolytic cell 1. The first discharge pipe 3 is connected to a water ejector 6, and an electrolytic product is supplied to the water ejector 6. Further, tap water is supplied to the water ejector 6, and the electrolytic product supplied from the first discharge pipe 3 is mixed, so that acidic electrolyzed water is generated and discharged from the water ejector 6. Further, a second discharge pipe 5 is connected to the water ejector 6, and the second discharge pipe 5 is connected to the storage tank 4. That is, the acidic electrolyzed water discharged from the water ejector 6 is discharged after being stored in the storage tank 4 through the second discharge pipe 5. Hereafter, each member which comprises this system is demonstrated in detail.

  First, the electrolytic cell 1 will be described. FIG. 2 is an exploded view of the electrolytic cell, and FIG. 3 is a cross-sectional view of the electrolytic cell. As shown in FIGS. 2 and 3, the electrolytic cell 1 includes first and second support blocks 11 and 12, and an electrode and an electrolytic solution are placed in an internal space 13 formed by combining them. Be contained. More details are as follows.

  The 1st support block 11 is formed in the rectangular parallelepiped shape where a pair of surface formed in square shape opposes. In the following, of one of the square surfaces, the surface facing the second support block 12 is referred to as an inner surface 111, and the surface opposite to the inner surface 111 is referred to as an outer surface 112. This name is also the same in the second support block 12. Since the 1st support block 11 and the 2nd support block 12 are the substantially the same structures, below, the 1st support block 11 is demonstrated in detail and only a different point is demonstrated about the 2nd support block 12.

  A circular first recess 113 is formed on the inner surface 111 of the first support block 11, and a rectangular second recess 114 is further formed on the bottom surface of the first recess 113. A first through hole 115 and a second through hole 116 are formed in the bottom surface of the first recess 113 and the bottom surface of the second recess 114, respectively, so that the inner surface 111 side and the outer surface 112 side communicate with each other. It has become. The first through hole 115 is formed below the second recess 114.

  A circular groove 117 is formed on the outer peripheral edge of the first recess 113, and the O-ring 19 is disposed in the groove 117. A plate-like anode 14 is fitted into the second recess 114, and a conductive wire 141 inserted into the second through-hole 116 from the outer surface is connected to the anode 14. The surface of the anode 14 fitted into the second recess 114, that is, the surface facing the second support block 12 is located deeper than the inner surface 111 of the first support block 11. Further, the supply pipe 2 described above is connected to the first through hole 115.

  The 2nd support block 12 is also formed similarly to the 1st support block 11, and the difference is as follows. First, in the first recess 123 of the second support block 12, a first through hole 125 to which the first discharge pipe 3 is connected is formed above the second recess 124. The second recess 124 accommodates a plate-like cathode 15, and a conductive wire 151 inserted into the second through hole 126 from the outer surface 122 is connected to the cathode 15. Similarly to the first support block 11, the surface of the cathode 15 fitted into the second recess 124, that is, the surface facing the first support block 11 is located deeper than the inner surface 121 of the second support block 12.

  The 1st and 2nd support blocks 11 and 12 comprised as mentioned above are arrange | positioned so that inner surface 111,121 may contact, and several 3rd through-hole formed in the outer side of 1st recessed part 113,123 The bolts 17 and the nuts 16 inserted through 118 and 128 are fixed to each other. And as shown in FIG. 3, the internal space 13 is formed in the electrolytic cell 1 by combining the 1st recessed part 113,123 formed in each support block 11,12. At this time, since the gasket 19 described above is disposed in the grooves 117 and 127 formed on the outer circumferences of the first recesses 113 and 123, the internal space 13 is held liquid-tight by the gasket 19. Further, as described above, since the surfaces of the anode 14 and the cathode 15 are deeper than the inner surfaces of the first support block 11 and the second support block 12, respectively, the anode 14 and the cathode 15 in the internal space 13. A gap is formed between the two. Then, the electrolytic solution is supplied to the internal space 13 from the supply pipe 2 connected to the first through hole 115 of the first support block 11. On the other hand, the electrolytic product generated in the internal space 13 is discharged from the first discharge pipe 3 connected to the first through hole 125 of the second support block 12.

  In addition, the material which comprises the electrodes 14 and 15 is not specifically limited, A well-known material is used. Thus, the electrolytic cell 1 is used for electrolysis as a so-called single-chamber electrolytic cell. Further, the supply of the electrolytic solution from the supply pipe 2 to the electrolytic cell 1 is performed based on the voltage between the electrodes. That is, when the voltage drops, a predetermined amount of electrolyte is supplied to the electrolytic cell 1 through the supply pipe 2. When the electrolytic solution is supplied to the electrolytic cell 1, the electrolytic product is discharged from the electrolytic cell 1 to the first discharge pipe 3 based on the electrolytic solution. Alternatively, the electrolytic solution can be supplied from the supply pipe 2 to the electrolytic cell 1 at a predetermined timing. In general, the discharge amount of the electrolytic product from the electrolytic cell 1 to the first discharge pipe 3 is smaller than the supply amount of the electrolytic solution from the supply pipe 2 to the electrolytic cell 1.

  Next, the water ejector 6 will be described. As the water ejector 6, a known one can be used. By supplying a high-pressure liquid, a low-pressure gas is sucked and a gas mixed with the liquid is discharged. As shown in FIG. 1, the water ejector 6 according to the present embodiment includes a main pipe 61 through which tap water passes and a connecting pipe 62 connected perpendicularly to the outer peripheral surface of the main pipe 61. The tap water is supplied at a high pressure from the supply hole 611 at one end of the main pipe 61, and the above-described first discharge pipe 3 is connected to the connecting pipe 62.

  Next, the storage tank will be described. The storage tank 4 has a rectangular parallelepiped internal space 411, the second discharge pipe 5 described above is connected to the side surface of the storage tank 41, and the acidic electrolyzed water discharged from the water ejector 6 is stored in the internal space 411. Supplied. On the other hand, a third discharge pipe 7 is connected to the upper surface of the storage tank 4 and communicates with the internal space 411.

  The volume of the internal space 411 of the storage tank 4 is set as follows. That is, when the flow rate of the acidic electrolyzed water discharged from the water ejector 6 is S (L / second) and the discharge cycle of the electrolytic product discharged from the electrolytic cell 1 to the first discharge pipe 3 is t (second), It is preferably S × t (L) or more, more preferably 2 × S × t (L) or more, and particularly preferably 3 × S × t (L) or more.

<2. Operation of electrolyzed water generation system>
Next, the operation of the system configured as described above will be described. First, the anode 14 and the cathode 15 are energized. Subsequently, the electrolytic solution is supplied from the supply pipe 2 to the electrolytic cell 1. The electrolyte used here can be, for example, dilute hydrochloric acid having a concentration of 2 to 6%.

Thus, when the electrolytic solution is supplied to the electrolytic cell 1, electrolytic treatment is performed in the internal space 13 of the electrolytic cell 1. Specifically, the following reaction occurs at the anode 14 and the cathode 15 to generate an electrolytic product containing hydrochloric acid, chlorine, and hydrogen. Chlorine is generated by the decomposition of hypochlorous acid in water.
2HCl + H ₂ O → HClO + HCl + H ₂

  Thus, the produced | generated electrolysis product is discharged | emitted from the 1st through-hole 125 of the 2nd support block 12 to the 1st discharge pipe 3, and is supplied to the water ejector 6. FIG. Here, since tap water is pumped to the main pipe 61 of the water ejector 6, the electrolytic product is sucked into the main pipe 61 from the connecting pipe 62 and mixed with the tap water. And the tap water with which the electrolysis product was mixed is discharged | emitted through the 2nd discharge pipe 5 from the discharge hole 612 of the main pipe 61 of a water ejector as acidic electrolysis water.

  Thereafter, the acidic electrolyzed water discharged from the water ejector 6 is continuously discharged through the third discharge pipe 7 after being stored in the storage tank 4.

<3. Features>
As described above, according to the present embodiment, the following effects can be obtained. First, since the electrolytic product is discharged from the electrolytic cell 1 at a predetermined cycle, when the electrolytic product is mixed with tap water in the water ejector 6, the generated acidic electrolytic water is discharged at a timing of being discharged from the water ejector 6. The pH will be different. That is, the acidic electrolyzed water immediately after mixing the electrolysis product and the acidic electrolyzed water just before the electrolysis product is mixed next have a different pH. Therefore, in the present embodiment, the storage tank 4 is provided on the downstream side of the water ejector 6. In this storage tank 4, the flow rate of acidic electrolyzed water discharged from the electrolytic cell 1 is S (L / second), and the discharge cycle of the electrolytic product discharged from the electrolytic cell 1 to the first discharge pipe 3 is t (seconds). , The volume is not less than S × t (L). Therefore, for example, the acidic electrolyzed water generated at least between the time when the electrolytic product is mixed with the water to be treated and the time when the next electrolytic product is mixed is once stored in the storage tank 4 and then discharged. Therefore, in the storage tank 4, acidic electrolyzed water in which the injection amount of the electrolytic product is averaged is generated. Therefore, the dispersion | variation in pH of the electrolytic product discharged | emitted from the storage tank 4 can be suppressed. In particular, since the dispersion of pH can be suppressed as the volume of the storage tank 4 increases, it is preferably 2 × S × t (L) or more and 3 × S × t (L) or more. However, if it becomes too large, the apparatus becomes larger, so it is preferable that it be smaller than 5 × S × t (L).

<4. Modification>
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various change is possible unless it deviates from the meaning.

<4-1>
For example, in the said embodiment, although the storage tank 4 is formed in the rectangular parallelepiped shape, it is not specifically limited. That is, the shape is not particularly limited as long as it has a volume as described above, and the connection positions of the second discharge pipe 5 and the third discharge pipe 7 are not particularly limited.

<4-2>
In addition, a stirring means for forcibly stirring the acidic electrolyzed water in the storage tank 4 may be provided. For example, as shown in FIG. 4A, a baffle plate 42 may be provided in the storage tank 4 so that acidic electrolyzed water passes through a predetermined route and is discharged. Thereby, acidic electrolyzed water is stirred inside the storage tank. Moreover, as shown in FIG.4 (b), the acidic electrolyzed water in the storage tank 4 can also be stirred by providing the impeller 43 and rotating this.

<4-3>
The configuration of the electrolytic cell 1 is not particularly limited, and can be applied to the present invention as long as it is a one-chamber type electrolytic cell capable of performing an electrolytic treatment with an electrolytic solution containing hydrochloric acid.

<4-4>
Moreover, in the said embodiment, although gas and tap water are mixed using the water ejector 6, it is not limited to this, The apparatus which can mix gas and liquid should just be used. Moreover, although tap water is used as a medium for mixing gas, water other than tap water prepared for electrolyzed water may be used.

  Examples according to the present invention will be described below. However, the present invention is not limited to the following examples.

  In the following Examples 1 and 2, acidic electrolyzed water was generated using the system shown in FIGS. The difference between Examples 1 and 2 is the size of the storage tank. Moreover, the system which removed the storage tank from the system of Example 1, 2 was used as a comparative example. In other configurations, the example and the comparative example are the same.

The system configuration is as follows.
・ Anode and cathode 5cm × 5cm plate ・ Distance between anode and cathode 2mm
・ Electric setting for anode and cathode Voltage 1.94V, current 2A
・ Tap water flow rate 2L / min (0.033L / sec)
・ Concentration of dilute hydrochloric acid as electrolyte 6%
・ Inner diameter of the first discharge pipe 4mm
-Shape of the storage tank (Example 1) A rectangular parallelepiped (volume 0.32 L) whose internal space is 72 mm long, 67 mm wide, and 67 mm high
-Shape of storage tank (Example 2) A rectangular parallelepiped (volume: 0.25 L) with an internal space of 140 mm in length, 42 mm in width, and 42 mm in height
-Pump discharge rate for supplying electrolyte from the supply pipe to the electrolytic cell 1.28mL / min

  Using the system configured as described above, acidic electrolyzed water discharged from the water ejector was sampled every 5 seconds from the start of electrolysis, and the water temperature, pH, and effective chlorine concentration were measured. The results are as follows. In Examples 1 and 2 and the comparative example, the discharge cycle of the electrolytic product from the electrolytic cell to the first discharge pipe was set to 3.75 seconds. Therefore, 0.124 L (= 0.033 L / sec × 3.75 sec) of acidic electrolyzed water once the electrolyzed product is mixed with tap water until the next electrolyzed product is mixed. Is caused to flow into the third discharge pipe. That is, the amount of acidic electrolyzed water generated in one cycle is 0.124L.

  According to Table 1, in the systems according to Examples 1 and 2, the pH and the effective chlorine concentration are both stable, but in the comparative example, both the pH and the effective chlorine concentration are varied. The difference between the value and the minimum value extends to 3.19. This is because the volume of the storage tank in Examples 1 and 2 is larger than 0.124 L, which is the amount of acidic electrolyzed water generated in one cycle (Example 1: 0.32 L> 0.124 L, Example 2: 0.25L> 0.124L), which is considered to be because the amount of electrolytic product is averaged in the storage tank. Therefore, in the system which concerns on these Examples, it turned out that a storage tank acts effectively and pH of the produced | generated acidic electrolyzed water is stable.

DESCRIPTION OF SYMBOLS 1 Electrolysis tank 3 1st discharge pipe 4 Storage tank 411 Internal space 6 Water ejector (mixing part)

Claims (4)

An electrolytic cell having an anode and a cathode, wherein no diaphragm is provided between the anode and the cathode;
A supply pipe for supplying an electrolytic solution containing hydrochloric acid to the electrolytic cell;
A discharge pipe for discharging the electrolytic product generated by electrolytic treatment in the electrolytic cell from the electrolytic cell;
A mixing unit for mixing the electrolytic product discharged from the discharge pipe with the water to be treated to generate acidic electrolyzed water;
While containing the acidic electrolyzed water discharged from the mixing unit, a storage tank for continuously discharging,
With
When the flow rate of the acidic electrolyzed water discharged from the mixing unit is S (L / second) and the discharge cycle of the electrolytic product discharged from the electrolytic tank to the discharge pipe is t (second), the storage tank An electrolyzed water generation system in which the volume of is not less than S × t (L).   The electrolyzed water generation system according to claim 1, wherein a volume of the storage tank is 2 × S × t (L) or more.   The electrolyzed water generation system according to claim 1, wherein the storage tank includes a stirring unit that stirs the acidic electrolyzed water to be stored. Supplying an electrolytic solution containing hydrochloric acid to an electrolytic cell having an anode and a cathode, and a partition wall is not provided between the anode and the cathode;
In the electrolytic cell, performing an electrolytic treatment to produce an electrolysis product;
Discharging the electrolytic product from the electrolytic cell every t (seconds);
Mixing the electrolytic product with the water to be treated to generate acidic electrolyzed water, and discharging the acidic electrolyzed water at a flow rate of S (L / sec);
Storing the acidic electrolyzed water in a storage tank having a volume of S × t (L) or more and continuously discharging the acidic electrolyzed water;
An electrolyzed water generation method comprising: