JP2009050797A - Apparatus and method for generating electrolytic water - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus in which the amount of salt to be non-electrolyzed and consumed uselessly is made small, a complicated structure and control are not needed, generation of a chlorine odor is restrained in a salt water tank, so that unpleasantness due to the chlorine odor is eliminated when salt is thrown in the salt water tank, and to provide a method for generating electrolytic water. <P>SOLUTION: The apparatus for generating electrolytic water is provided with: an electrolytic cell having an intermediate chamber, an anode chamber and a cathode chamber; the salt water tank in which salt is brought into contact with the salt water to be circularly supplied to the intermediate chamber to increase salt concentration of the salt water; a supply line for supplying the salt water to the intermediate chamber from the salt water tank; a return line for returning the electrolyzed salt water to the salt water tank from the intermediate chamber; a replenishment line for taking a part of the alkaline water discharged from the cathode chamber in the salt water tank; and a discharge line for keeping fixed the water level of the salt water tank. Connection ports of the return line, the replenishment line and the discharge line to the salt water tank are arranged in the positions higher than the upper surface of the undissolved salt accumulated in the salt water tank. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electrolyzed water generating apparatus and an electrolyzed water generating method.

2. Description of the Related Art Conventionally, an electrolyzed water generating apparatus that generates an acidic solution or an alkaline solution by electrolyzing saline is known. The electrolyzed water generating apparatus has an electrolyzer represented by a so-called two-chamber type and three-chamber type, and supplies salt water to the electrolyzer to obtain desired electrolyzed water.
FIG. 14 is a schematic diagram showing a two-chamber electrolytic cell 100. In the case of the two-chamber type electrolytic cell, the inside of the electrolytic cell is divided into two chambers by a diaphragm 101, and an anode chamber 104 and a cathode chamber 105 are formed in each chamber by arranging an anode 102 and a cathode 103, respectively. is there. A saline solution is supplied to the anode chamber 104 and the cathode chamber 105 from a salt water tank 106, respectively. Although a part of the supplied saline solution is electrolyzed, it is not electrolyzed in the discharged acidic water or alkaline water. The salt component was contained as it was.
In the experiment conducted by the applicant, the electrolyzed water generating apparatus using the two-chamber electrolytic cell has a pH of 2.7 or less, which is a standard as strongly acidic hypochlorous acid water (strongly acidic electrolyzed water) in the Food Sanitation Law. It was found that approximately 1500 g / min (180 g per hour) of salt was consumed to produce 1500 mL of an acidic solution with an effective chlorine concentration of 20 to 60 mg / kg per minute.

Moreover, the electrolyzed water generating apparatus of patent document 1 is known as what uses a three-chamber type electrolyzer. The electrolyzed water generating apparatus includes, as main constituent members, an electrolyzer and a salt water tank that stores electrolysis salt water and a pipe that connects them. Saturated saline is supplied from the concentrated salt water tank to the salt water tank via a communication pipe having an open / close valve, and water is appropriately supplied through a water supply pipe having a water supply valve. And according to the detection result of the concentration sensor provided in the salt water tank, the open / close valve and the water supply valve are operated to maintain the concentration and water level of the salt water in the salt water tank within a predetermined range.
Further, the salt water tank has a stirring pump for uniformizing the internal concentration, and a salt tank for supplying salt to the concentrated salt water tank is also provided. In addition, a pH sensor is provided in the salt water tank, and acid water or alkaline water is supplied to the salt water tank by controlling the acid water supply valve or the alkaline water supply valve according to the detected value. Is kept within a certain range.
Japanese Patent Laid-Open No. 7-299457

In the case of the above-described two-chamber electrolytic cell, there is a problem that the amount of salt consumed is large with respect to the amount of the acidic solution or alkaline solution produced. In addition, the electrolyzed water generating device described in Patent Document 1 has a drawback that the configuration and control of the device are complicated, such as operating various valves according to the detection result by the sensor, and the product price and maintenance cost are expensive. Have.
The present invention has been invented in view of the above problems, and reduces the amount of salt that is wasted while remaining unelectrolyzed, and does not require complicated structure and control with many auxiliary means such as sensors and valves. It is an object to provide a water generator and the like. It is another object of the present invention to eliminate the unpleasant feeling caused by the chlorine odor when the salt is added by discharging the component that causes the generation of the chlorine odor from the salt water tank containing the salt.

In order to solve the above problems, an electrolyzed water generating apparatus according to claim 1 of the present application has the following configuration. That is,
An electrolytic cell comprising an intermediate chamber for circulating and supplying saline, an anode chamber adjacent to the intermediate chamber via a diaphragm and an anode, and a cathode chamber adjacent to the intermediate chamber via a diaphragm and a cathode;
A salt water tank that raises the concentration of the salt solution by bringing salt into contact with the salt solution that circulates and supplies the intermediate chamber;
A supply path for supplying saline to the intermediate chamber from the salt water tank;
A return path for returning the salt water after electrolytic treatment from the intermediate chamber to the salt water tank;
A replenishment path for taking a portion of the alkaline water discharged from the cathode chamber into a salt water tank;
A discharge path for maintaining a constant water level in the salt water tank,
The said salt water tank provided the connection port with the said return path, a replenishment path, and a discharge path above the upper surface of the undissolved salt accumulated inside, The electrolyzed water generating apparatus characterized by the above-mentioned.

Moreover, the electrolyzed water generating apparatus of Claim 2 of this application has the following structures. That is,
An electrolytic cell comprising an intermediate chamber for circulating and supplying saline, an anode chamber adjacent to the intermediate chamber via a diaphragm and an anode, and a cathode chamber adjacent to the intermediate chamber via a diaphragm and a cathode;
A salt water tank that raises the concentration of the salt solution by bringing salt into contact with the salt solution that circulates and supplies the intermediate chamber;
A supply path for supplying saline to the intermediate chamber from the salt water tank;
A return path for returning the salt water after electrolytic treatment from the intermediate chamber to the salt water tank;
A replenishment path for taking a part of the raw water supplied to the anode chamber and the cathode chamber into a salt water tank;
A discharge path for maintaining a constant water level in the salt water tank,
The said salt water tank provided the connection port with the said return path, a replenishment path, and a discharge path above the upper surface of the undissolved salt accumulated inside, The electrolyzed water generating apparatus characterized by the above-mentioned.

Moreover, the electrolyzed water generating apparatus according to claim 3 of the present application has the following configuration. That is,
3. The electrolyzed water generating device according to claim 1, wherein the salt water tank is provided with a connection port with the replenishment path above a connection port with the discharge path.

Moreover, in order to solve the said subject, the electrolyzed water production | generation method of Claim 4 of this application has the following structures. That is,
An intermediate chamber that circulates and supplies saline, an anode chamber that is adjacent to the intermediate chamber via a diaphragm and an anode, an electrolytic cell that includes a cathode chamber that is adjacent to the intermediate chamber via a diaphragm and a cathode, and sodium chloride and the intermediate chamber A method for generating electrolyzed water in an electrolyzed water generating apparatus having a salt water tank that increases the concentration of the saline by bringing the saline into circulation with the solution,
The reduced amount of the solution in the salt water tank, which is reduced by electrolysis, is supplemented with part of the alkaline water discharged from the cathode chamber as make-up water, and the excess of the make-up water supplied in excess is salt water connected to the discharge path. A method for producing electrolyzed water, characterized in that it is discarded from a connection port of a tank.

Moreover, the electrolyzed water production | generation method of Claim 5 of this application has the following structures. That is,
The method for producing electrolyzed water according to claim 4, wherein the amount of makeup water is larger than the amount of solution in the salt water tank that actually decreases and is 7 times or less of the amount of solution.

In the electrolyzed water generating apparatus and the electrolyzed water generating method according to the present invention, a salt water tank that generates salt water by adding salt is formed as an overflow tank, and alkaline water or raw water generated in an alkaline chamber is added to the salt water tank. It is supplied as makeup water. The makeup water is supplied in an amount slightly larger than the amount of saline consumed by electrolysis or the like, and the surplus is discharged from the salt water tank by an overflow function. When discharging the surplus solution, the chlorine component that has entered the salt water tank is discharged together with the surplus solution, so that the chlorine component can be removed from the salt water tank. is doing. As a result, the chlorine odor generated in the salt water tank can be reduced.
In addition, the amount of salt that is wasted is reduced by setting the flow rate of make-up water to a range of about 7 times the amount of solution in the salt water tank that is actually reduced by electrolysis or the like. Has the effect of being able to.

  The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view showing an electrolyzed water generating device according to the present invention, and 1 shows the electrolyzed water generating device. The electrolyzed water generating apparatus 1 is mainly composed of an electrolyzer 2, a salt water tank 3, various pipes, and an electrical control means 20.

The electrolytic cell 2 is configured as a so-called three-chamber electrolytic cell, and includes an intermediate chamber 4 for supplying saline, an anode chamber 5 for generating an acidic solution containing effective chlorine such as hypochlorous acid, and an alkaline solution. It has a cathode chamber 6 to be produced. The intermediate chamber 4 and the anode chamber 5 are partitioned by a diaphragm 7 that functions as an anion exchange membrane. An anode plate 8 that functions as an electrode is provided in the anode chamber 5. The diaphragm 7 and the anode plate 8 are arranged close to each other. Similarly, the intermediate chamber 4 and the cathode chamber 6 are partitioned by a diaphragm 9 that functions as a cation exchange membrane. A cathode plate 10 that functions as an electrode is provided in the cathode chamber 6. The diaphragm 9 and the cathode plate 10 are arranged close to each other.
There are various materials that can be used as the diaphragms 7 and 9, but the salt water in the intermediate chamber 4 becomes acidic depending on the combination of the diaphragm provided on the anode chamber 5 side and the diaphragm provided on the cathode chamber 6 side. Become neutral or alkaline. In the embodiment of the present application, the diaphragm 7 provided on the anode chamber 5 side and the diaphragm 9 provided on the cathode chamber 6 side are selected in such a combination that the inside of the intermediate chamber 4 is acidic. This is because if the salt water in the intermediate chamber 4 shows alkalinity, magnesium, calcium or the like may be deposited as a scale and hinder the function of the electrolytic cell.

FIG. 2 is an explanatory diagram showing an example of the salt water tank 3. The salt water tank 3 is a tank having a function of supplying saturated saline to the intermediate chamber 4 of the electrolytic cell 2.
2 (a) is a front view, FIG. 2 (b) is a side view, FIG. 2 (c) is a sectional view taken along the line CC in FIG. 2 (b), FIG. 2 (d) is a plan view, and FIG. Fig. 2A is a cross-sectional view taken along line AA in Fig. 2A, and Fig. 2F is a cross-sectional view taken along line BB in Fig. 2A. FIG. 2 (f) shows a state in which salt and water are put in the salt water tank 3, and there are roughly three layers of a solid salt layer (S), a liquid layer (L), and a gas layer (G). The formed state is shown.
A salt water discharge port 11 is provided at the bottom of the salt water tank 3, and is connected to a pipe (supply path 12) connected to the intermediate chamber 4 through a pipe joint. The salt water discharge port 11 is provided with a filter 13 that prevents permeation of solid salt so that only the liquid component in the tank permeates the supply path 12. A pump P <b> 1 that is operated under the control of the control means 20 is arranged in the middle of the pipe constituting the supply path 12, and saline is sent to the intermediate chamber 4 by driving the pump P <b> 1.

Above the inner surface of the salt water tank 3, a return port 14, a supply port 15 and a discharge port 16 are provided.
The return port 14 is an opening connected to a pipe (return path 17) provided between the intermediate chamber 4 and the salt water tank 3, and serves as a part for returning the solution in the intermediate chamber 4 into the salt water tank 3.
The replenishing port 15 is an opening connected to a pipe (replenishment path 18) provided between the cathode chamber 6 and the salt water tank 3, and serves as a part for allowing a part of the generated alkaline water to flow into the salt water tank 3. ing. A pump P <b> 2 is arranged in the middle of the pipe constituting the replenishment path 18, and replenishment water (a part of alkaline water) is sent to the salt water tank 3 by the operation of the pump P <b> 2 based on the control of the control means 20. ing.
The discharge port 16 is an opening provided on the inner surface of the salt water tank 3, and is an opening connected to a drain pipe (not shown) for discarding the solution. When the liquid level reaches the discharge port 16, the discharge port 16 is exceeded. The solution is discarded. That is, the salt water tank 3 functions as an overflow tank that keeps the water level below a certain level by providing the discharge port 16.

The return port 14, the replenishment port 15, and the discharge port 16 are provided at positions sufficiently high from the salt water discharge port 11. Each port is provided at a position above the upper surface of undissolved salt (S) accumulated in the salt water tank 3.
The discharge port 16 has an overflow function for determining the upper limit of the water level in the salt water tank 3. In this embodiment, the discharge port 16 is provided at a position slightly lower (20 to 30 mm) than the return port 14 and the supply port 15. ing. The return port 14 and the replenishment port 15 are provided at close positions at the same height, and are provided on one inner side surface of the salt water tank 3 formed in a rectangular parallelepiped shape.

Next, circulation and the like of each solution in the electrolyzed water generating apparatus 1 having the above configuration will be described.
The electrolyzed water generating apparatus 1 according to the present embodiment is an apparatus that generates acidic water satisfying a pH of 2.7 or less and an effective chlorine concentration of 20 to 60 mg / kg and alkaline water generated simultaneously at a rate of 1500 mL per minute. . For this reason, 3000 mL of raw water per minute is introduced into the raw water introduction unit 19 of the electrolyzed water generator 1 shown in FIG. As water used as raw water, tap water supplied by a water supply through a water softener is used.
In addition, in order to generate a certain amount of acidic water and alkaline water per minute, it is necessary to electrolyze a certain amount of salt, and between the anode chamber 5 and the cathode chamber 6 in order to electrolyze the certain amount of salt. A certain amount of current flows. The electrolyzed water generating apparatus 1 automatically controls the voltage between the anode chamber 5 and the cathode chamber 6 by the control means 20, thereby making the current value flowing between the electrode plates constant according to the electric resistance of the changing saline solution. To keep.
The control means 20 reduces the electric resistance when the concentration of the saline solution in the intermediate chamber 4 is high, so that the voltage between the anode chamber 5 and the cathode chamber 6 is lowered, and the electric resistance when the concentration of the saline solution is low. Therefore, the current value is controlled to be constant by increasing the voltage between the anode chamber 5 and the cathode chamber 6.

  The solution supplied from the salt water tank 3 to the intermediate chamber 4 via the supply path 12 is a saturated saline solution generated in the salt water tank 3. The saturated saline is supplied to the intermediate chamber 4 by the pump P1 controlled by the control means 20 provided in the supply path 12 and returned to the salt water tank 3 through the return path 17. At this time, since the salt solution in the intermediate chamber 4 consumes a salt component by electrolysis, the salt solution is returned to the salt water tank 3 in a state where the concentration of salt is lowered and the volume is slightly reduced. Then, a part of the solution returned to the salt water tank 3 is discarded, and the solution that has not been discarded becomes saturated saline in the salt water tank 3 and then returns to the intermediate chamber 4 via the supply path 12 as a circulating solution. Supplied.

As described above, the electrolyzed water generating apparatus 1 is designed with specifications that continuously generate 1500 mL of strongly acidic electrolyzed water (pH 2.7 or less, effective chlorine concentration 20 to 60 mg / kg) per minute by electrolytic treatment of saline solution. A current of about 10.5 (A) is continuously passed between the electrode plates.
The energization causes various reactions in the electrolytic cell. The main reaction of NaCl (salt) is NaCl → Na ⁺ + Cl ^{− in the} intermediate chamber.
In the vicinity of the anode, 2Cl ⁻ → Cl ₂ + 2e ⁻ .
From the Faraday's law of electrolysis, the amount of salt consumed based on the current value can be calculated by the following equation.
n = m / M = It / zF
In the above formula, n [mol] = substance amount, I [A] = current (10.5), m [g] = mass, t [s] = time, M [g / mol] = molecular weight (NaCl is 58.5), z = ion valence, F = 9.65 × 10 ⁴ [C / mol], and the mass of salt consumed per minute derived from the above equation is 0.38 g.

Moreover, since the salt concentration of the saturated saline solution at 20 ° C. is 26.4%, the weight of the saturated saline solution containing the salt (0.38 g) determined by the above calculation is 1.44 g. Furthermore, when the specific gravity of the saturated saline solution discharged from the pump P1 of the supply path 12 was measured, it was 1.19 (g / cm ³ ). From the above results, it was found that the volume (theoretical value) of saturated saline used for 1 minute was approximately 1.44 / 1.19 = 1.21 mL. That is, when the acidic water having the above specifications is generated, assuming that all the salt contained in the saturated saline is electrolyzed, the amount of the saturated saline required per minute is about 1.21 mL.
However, since the electrical resistance value of the solution increases as the concentration of the saturated saline decreases, the voltage must be increased to generate a certain amount of electrolyzed water, which increases the load on the apparatus and increases the efficiency of electrolysis. It drops significantly.
Therefore, in the present embodiment, from a comprehensive viewpoint such as the life of the apparatus, electrolysis efficiency, etc., approximately 5 mL of saturated saline solution is provided in terms of equivalent to approximately 4 times the theoretical value, and the efficiency is improved. Electrolyzed water is often generated.

FIG. 3 (1) briefly shows the saturation of the saline solution (100 when the salt is saturated and 0 when the salt is not contained) and the fluctuation of the voltage acting between the anode plate 8 and the cathode plate 10. It is a graph. That is, in the same figure, the electrical resistance increases to R1, R2, R3 (R1 <R2 <R3) as the degree of saturation of the saline solution decreases, and the voltage also increases to V1, V2, V3 (V1 <V2). <V3) represents a rising state. The portion indicated by the dotted line on the graph is a theoretical portion, and actually the apparatus is stopped as an abnormal rise in voltage. Therefore, in the case of an actual apparatus, operation in this region is not performed.
FIG. 3 (2) shows the relationship between the saturation of the saline solution and the current value flowing between the electrodes. During normal operation with a voltage of V3 or lower, the value of the current flowing between the electrodes is substantially constant.
The electrolyzed water generating apparatus 1 shown in Example 2 described later maintains the saline concentration in the intermediate chamber 4 within a certain range, whereby the voltage between the electrodes during normal operation is within a certain amplitude (V1 (V2 ) To V3), and it is determined that the conditions such as the life of the electrolytic cell, the failure, the decrease in the concentration of the saline solution, etc. have occurred on the condition that the voltage value significantly exceeds V3. Is supposed to stop. As described above, when the voltage between the electrodes is equal to or lower than V3, the operation is continued assuming that the normal operation is performed.

Further, the electrolytic cell 2 generates alkaline water in the cathode chamber 6 together with the generation of the strongly acidic electrolyzed water described above. Then, a part of the alkaline water is supplied to the salt water tank 3 through the supply path 18 as supply water. The alkaline water supply port 15 provided in the salt water tank 3 is provided above the discharge port 16 that allows the salt water tank 3 to function as an overflow tank.
The electrolyzed water generating apparatus 1 consumes the salt in the salt water tank 3 as the electrolyzed water is generated as described above. Further, the volume of the solution circulating in the salt water tank 3 and the intermediate chamber 4 also decreases due to electrolysis of the water itself, diaphragm permeation, evaporation and the like.
The salt water tank 3 is supplied with a solution after electrolytic treatment that has passed through the intermediate chamber 4 and makeup water that is alkaline water. The solution that has passed through the intermediate chamber 4 contains a chlorine component generated by electrolysis, a salt component remaining in the intermediate chamber 4 without moving to the acidic chamber or the alkaline chamber, and the like.
Among these components returned to the salt water tank 3, the salt component has a higher concentration of circulating water than the salt water concentration in the vicinity of the surface of the salt water tank, so that before the circulating water returns to the salt water tank 3, it diffuses. Sink in. In addition, since the circulating water is diluted with makeup water and a part of the diluted circulating water is discharged, the consumption amount of salt is less than that when the circulating water is discharged without being circulated. Since this discharged solution contains chlorine components in the salt water tank 3, the chlorine odor in the salt water tank 3 is reduced by discharging these components.

FIG. 4 shows the flow of make-up water that compensates for the decrease in circulating water, the amount of salt consumed, and whether the water level in the salt water tank 3 can be maintained by supplying make-up water (water level stability) is indicated by ○ ×. FIG. 4 (1) circulates between the salt water tank 3 and the intermediate chamber 4 when the supply amount of circulating water circulating between the salt water tank 3 and the intermediate chamber 4 is 1.1 mL / min. The case where the supply amount of circulating water is 47 mL / min is shown.
As shown in Fig. 4 (1) and Fig. 4 (2), the flow rate of make-up water is less than 0.7 mL / min regardless of whether the supply of circulating water is 1.1 mL / min or 47 mL / min. In some cases, the overflow position in the salt water tank 3 cannot be maintained and the water level is lowered. That is, in order to keep the water level in the salt water tank 3 constant, the flow rate of makeup water is required to be 0.7 mL / min or more. Moreover, when the supply amount of circulating water was compared with the case of 1.1 mL / min and the case of 47 mL / min, the former showed the tendency for salt consumption to be small.

FIG. 5 (1) is a graph when an experiment for determining the minimum circulation amount (circulation water supply amount) required by the electrolyzed water generating apparatus is performed. FIG. 5 (2) summarizes the results found from the experiment. It is a table. In FIG. 5 (1), A represents each data curve with a circulation rate of 1.0 mL / min, B represents 1.1 mL / min, and C represents 1.2 mL / min.
When the circulation rate is 1.0 mL / min, the continuous operation is automatically stopped because the voltage between the electrode plates exceeds the preset 10 V during the operation. This is because the amount of the saline solution supplied to the intermediate chamber 4 is small, the salt concentration necessary for electrolysis is reduced, and the electrical resistance is increased.
In addition, when the circulation rate is 1.1 mL / min and 1.2 mL / min, the voltage between the electrode plates during operation is maintained within a predetermined range, and the salt concentration required for electrolysis is maintained. I understand.

  As described above, in the case of the electrolyzed water generating apparatus according to the present embodiment, the minimum circulating amount of circulating water necessary for continuing normal operation is approximately 1.1 mL per minute. Examples of the circulating water supply method include the methods of Example 1 and Example 2 shown below. Each will be described below.

Example 1 relates to the case where a pump having a rated capacity of 5 mL / min with a small discharge amount per unit time is used. The rated capacity is a flow rate that can be discharged when driven by a specified voltage.
FIG. 6 is a graph or the like showing the contents of control using the pump having the above specifications. FIG. 6 (1) shows a state in which alkaline water as makeup water is continuously supplied into the salt water tank 3 using a pump with a rated capacity of 5 mL / min. FIG. 6 (2) shows a state in which the saturated saline is continuously supplied to the intermediate chamber 4 using a pump with a rated capacity of 5 mL / min. FIG. 6 (3) shows that the voltage between the electrodes is stable (V4) regardless of the passage of time. FIG. 6 (4) shows that a constant current flows between the electrodes regardless of the passage of time. The horizontal axis of each graph is minutes.

In this embodiment, continuous operation is performed by using a pump with a relatively small discharge amount with a rated capacity of 5 mL / min for supplying circulating water and makeup water. Therefore, since the concentration of the salt component in the intermediate chamber is kept relatively constant, the voltage between the electrode plates shows a substantially constant value without undulation as shown in FIG. 6 (3).
The flow rate of saturated saline (approximately 5mL / min), current value (10.5A) and the amount of acidic water produced (1500mL per minute) are proportionally related. The flow rate of saturated saline changes proportionally.

Example 2 relates to the case where a pump with a rated capacity of 50 mL / min with a large discharge amount per unit time is used.
The minimum amount of saturated saline required for electrolysis is about 1.1 mL per minute. Therefore, it is sufficient to use the above-mentioned pump having a rated capacity of about 5 mL / min for supplying the saline solution.
However, since the intermediate chamber 4 of the electrolyzed water generating apparatus 1 according to the present embodiment has a volume of about 65 mL,
It takes approximately 13 minutes (65 ÷ 5) to fill the empty intermediate chamber 4 with saturated saline. This means that when the electrolytic cell is replaced or when the intermediate chamber 4 is emptied during maintenance, it takes at least 13 minutes to start normal operation again as an electrolytic device. It will cause a drop. Therefore, it is desirable to adopt an apparatus and a method that can realize both of being able to supply a necessary amount of saturated saline and supplying saturated saline at a high flow rate as necessary.
From the above idea, it is theoretically possible to obtain a flow rate of 5 mL / min continuously without interruption by driving a pump that exhibits a flow rate of 50 mL / min by driving at the rated voltage at a low voltage. . However, when a large pump is driven at a low voltage, the flow rate is not stable, and the desired flow rate cannot be obtained stably.

  The electrolyzed water generating apparatus 1 according to the second embodiment uses a pump that exhibits a flow rate of 50 mL / min by driving with a rated voltage as the pump P1 from the above viewpoint. By using the pump of the specification, even if it is necessary to fill the empty intermediate chamber 4 with saturated saline, the required time can be shortened from the conventional 13 minutes to about 1 minute 18 seconds. It has become. And by the method demonstrated below, the salt solution equivalent to 5 mL / min is supplied using the said pump.

  A method of supplying a saturated saline solution equivalent to 5 mL per minute to the intermediate chamber 4 using the pump that exhibits the flow rate of 50 mL / min will be described. That is, this method is an intermittent operation in which the rated operation and stop of the pump P1 are repeated in a constant cycle. Specifically, a cycle in which the pump P1 is operated for 1 minute and then stopped for 9 minutes is continuously repeated. As a result, the electrolyzed water generating apparatus 1 supplies about 50 mL of new saline every 10 minutes to the intermediate chamber 4 and replaces it with the same amount of old saline remaining in the intermediate chamber 4. ing.

FIG. 7 is a graph or the like when the operation is performed in a cycle in which the pump P1 with a rated flow rate of 50 mL / min is operated for 1 minute and then stopped for 9 minutes.
FIG. 7 (1) relates to alkaline water as makeup water. The pump with a rated capacity of 50 mL / min is synchronized with the supply of saturated saline solution shown in FIG. It shows a state where a cycle of supplying for 1 minute and resting for 9 minutes is repeated. Fig. 7 (2) shows a state in which saturated saline is intermittently supplied to the intermediate chamber 4 while repeating a cycle in which a pump with a rated capacity of 50 mL / min is operated for 1 minute and then stopped for 9 minutes. ing. FIG. 7 (3) shows a state in which the voltage between the electrodes changes in the range of V2 to V3 with the passage of time. That is, the voltage decreases as the saturated saline solution is supplied to the intermediate chamber 4, and the voltage gradually increases as the saturated saline solution stops being supplied. FIG. 7 (4) shows that a constant current flows between the electrodes regardless of the passage of time. The horizontal axis of each graph is minutes.
The electrolyzed water generating apparatus 1 according to the present embodiment detects the current value flowing between the anode plate 8 and the cathode plate 10 and causes the control means 20 to vary the voltage value as shown in FIG. As shown in FIG. 7 (4), the current value is kept constant.

  In addition, when the voltage value exceeds V3 and further exceeds a certain value (Vover) due to the deterioration of the diaphragm or electrode (lifetime) or the decrease in salt water concentration due to poor pump operation, the control means 20 stops the apparatus as an error. To do. The control means 20 performs various controls such as operation control of the pumps P1 and P2, detection of abnormal operation, and stop of the apparatus at the time of abnormal operation.

In the second embodiment, the pump P1 is operated for 1 minute at intervals of 10 minutes. That is, the saturated saline solution required for electrolysis is supplied by controlling the operation time of the pump P1 that operates at the rated discharge amount.
FIG. 8 is a graph showing the relationship between the operating time of the pump P1 having a rated discharge amount of 50 mL / min and the discharge amount. As described above, when the pump P1 is operated for 1 minute, the discharge amount is 50 mL, which is 5 mL / min when converted to an average of 10 minutes. As understood from the graph, the discharge amount by the pump P1 can be determined by the operation time.
For example, according to the experimental results described above, the minimum flow rate at which continuous operation is possible is 1.1 mL / min, but in order to obtain a circulating water amount equivalent to 1.1 mL / min, the pump P1 is set to 0.22 minutes every 10 minutes. (13.2 seconds) What is necessary is just to drive. That is, when a pump with a discharge rate of 50 mL / min is operated for 13.2 seconds, the discharge rate is 11 mL, which is 1.1 mL / min when converted into a flow rate per minute. However, in this embodiment, in order to operate the apparatus stably, circulating water equivalent to 5 mL / min, which is more than the minimum flow rate, is supplied.
In this example, the required flow rate is controlled by controlling the drive time of the pump in this way. The pump drive time is also controlled in the makeup water pump P2.

In Example 1 and Example 2 described above, on average, both circulating water (saturated saline) and makeup water are supplied at a flow rate of 5 mL / min. When the consumption of salt in this case was measured, it was found that 0.5 mg / min (30 g per hour) was consumed. This is about 1/6 of the consumption compared to the above-described two-chamber electrolytic cell, which indicates that the salt electrolysis is efficiently performed.
Moreover, the salt water tank used for the electrolyzed water generating apparatus 1 described above is designed so that the maximum input amount of salt is 7.5 kg. Therefore, when the continuous operation possible time in the case of no salt supply is calculated from the viewpoint of salt consumption, continuous operation for 250 hours is possible. Thus, reducing the consumption of salt has the effect of extending the continuous operation time of the electrolyzed water generating device 1 as well as saving the salt itself, and reducing the frequency of salt injection.

Next, the relationship between circulating water and makeup water will be described.
When circulating water and make-up water are supplied at a rate of 1.1 mL / min, which is equivalent to the actual decrease in the solution in the salt water tank, 13 g (corresponding to about 0.2 mg per minute) is measured when the amount of salt consumed per hour is measured. ) Was found to consume salt. This was about 1/2 compared with the case of the said Example 1 and Example 2, and was about 1/12 of salt consumption compared with the case of the two-chamber type electrolysis layer mentioned above. Therefore, in order to generate electrolyzed water using salt most efficiently, it can be said that it is ideal to supply make-up water substantially equivalent to the actual amount of decrease in the solution.

In the first and second embodiments described above, approximately the same amount of make-up water as the saturated saline solution sent to the intermediate chamber 4 is supplied to the salt water tank 3. The makeup water has a role of removing unnecessary components in addition to replenishing the solution in the salt water tank 3 to be consumed.
The electrolyzed solution that returns to the salt water tank 3 contains a slight amount of effective chlorine components such as hypochlorous acid that have passed through the diaphragm. When this enters the salt water tank 3, it smells due to the chlorine odor, and if the lid of the salt water tank 3 is opened when salt is added, the operator's odor is stimulated, giving a very unpleasant impression.
However, by supplying more makeup water than the minimum replenishment amount, the solution containing the chlorine component existing in the surface layer portion of the liquid layer (L) in the salt water tank 3 can be washed away, and the irritating odor caused by chlorine can be reduced. it can. Thus, by supplying more makeup water than the minimum replenishment amount, the chlorine odor in the salt water tank 3 can be reduced. The chlorine odor is strongly felt when the chlorine concentration of the solution in the salt water tank 3 is high.

FIG. 9 is a graph showing the relationship between the circulating amount of saline and the chlorine concentration of the solution in the salt water tank 3. The supply amount of make-up water is set to 1.1 to 1.0 mL in terms of minute so as to keep the water level in the salt water tank so as not to be discharged (overflow) wastefully from the discharge port 16.
Saline circulation rate is set to 3 patterns of 1.1mL, 8.2mL and 47mL per minute, and the chlorine concentration in the salt water tank after about 8 hours of operation is measured. The result is about 0.4mg / kg. , 0.8mg / kg, 0.7m
The result was g / kg. That is, the result that the chlorine concentration can be lowered when the amount of circulating saline is small is obtained.

In FIG. 10, the saline circulation rate is set to 1.1 to 1.0 mL per minute, which is about the minimum circulation rate, and alkaline water (make-up water) is converted into 1.1 mL, 8.2 mL, and 47 mL per minute. It is the table | surface showing the result of having actually measured the quantity of the salt supplied with a pattern and consumed every hour. As a result, it was found that when the makeup water flow rate was the lowest, 1.1 mL / min, the consumption of salt was reduced compared to other patterns.
When the amount of makeup water is 47 mL / min, the amount of salt consumed is slightly higher than 0.03 kg / h in the case of 8.2 mL / min, and in this range of 47 mL / min and 8.2 mL / min, the salt consumption is large. There is no difference. In addition, since the salt consumption greatly fluctuated from 1.1 mL / min to 8.2 mL / min (see Fig. 11), the makeup water flow rate was 8.2 mL / min. It is a changing condition.
In addition, when the amount of the replenishing water (1.1 mL / min to 8.2 mL / min) is expressed as a ratio to the amount of saline solution consumed (1.1 mL / min), it is approximately 1 to 7.5 times. That is, when the amount of makeup water is 1 to 7.5 times the amount of salt water consumed, the amount of salt consumed is compared with the case of supplying a large amount of makeup water. It can be reduced.
In the present embodiment, from the viewpoint of reducing the chlorine odor, the minimum amount of makeup water is set to be slightly larger than the actual consumption amount, and the surplus is discharged together with the substance that causes chlorine odor. In addition, the upper limit of makeup water derived from the viewpoint of salt consumption is 8.2 mL / min (approximately 7.5 times the amount of salt water consumed), but in actual operation it is consumed slightly less than this. The amount is preferably about 7 times or less of saline.

In addition, the amount of saline solution to be circulated is determined by low electrolysis voltage and high efficiency (low power consumption), low consumption of waste salt that is discarded without being electrolyzed, and chlorine odor in the salt water tank. Judgment is made by comprehensively considering that there are few. For example, in the example shown in Example 2, when the circulation rate of the saline solution is set to the minimum of 1.1 mL / min, the salt water concentration of the solution extremely decreases in the second half of the time when the operation of the pump P1 is stopped. As a result, the voltage between the plates increases. A high voltage during operation means that there is little difference from the upper limit value (Vover) of the voltage for ensuring the safety of the device, and there is little room for the device.
In the present embodiment, the saline circulation rate is set to be equivalent to 5 mL per minute from the above viewpoint.

In the example shown in the second embodiment, the pump P1 having a rated flow rate of 50 mL / min is operated for 1 minute and then is stopped for 9 minutes. The intermittent control pattern is the same as the above-described example. Not limited. FIG. 12 is a graph corresponding to FIG. 7 described above, but as shown in FIG. 12, a cycle of supplying circulating water for 30 seconds at intervals of 5 minutes may be repeated.
Although not shown in the drawings, the makeup water supply pattern may be performed every 5 minutes for 30 seconds.
Furthermore, in this embodiment, pumps of the same specification are used as pumps for circulating water and makeup water. However, since this is simply concerned about errors during assembly, pumps with different specifications are used. Each of them may be used for obtaining a necessary flow rate.

Next, another embodiment relating to the electrolyzed water generating apparatus according to the present invention will be described with reference to FIG. The electrolyzed water generating apparatus 30 of the present embodiment is the same as the electrolyzed water generating apparatus shown in FIG. The electrolyzed water generator 30 is different from the electrolyzed water generator shown in FIG. 1 in that raw water is supplied to the salt water tank 3 as makeup water.
That is, the electrolyzed water generating apparatus 30 is mainly composed of the electrolyzer 2, the salt water tank 3, various pipes, and the electrical control means 20.
The electrolytic cell 2 is configured as a so-called three-chamber electrolytic cell, and includes an intermediate chamber 4 for supplying saline, an anode chamber 5 for generating an acidic solution containing effective chlorine such as hypochlorous acid, and an alkaline solution. It has a cathode chamber 6 to be produced. The intermediate chamber 4 and the anode chamber 5 are partitioned by a diaphragm 7 that functions as an anion exchange membrane. An anode plate 8 that functions as an electrode is provided in the anode chamber 5. The diaphragm 7 and the anode plate 8 are arranged close to each other. Similarly, the intermediate chamber 4 and the cathode chamber 6 are partitioned by a diaphragm 9 that functions as a cation exchange membrane. A cathode plate 10 that functions as an electrode is provided in the cathode chamber 6. The diaphragm 9 and the cathode plate 10 are arranged close to each other.
There are various materials that can be used as the diaphragms 7 and 9, but the salt water in the intermediate chamber 4 becomes acidic depending on the combination of the diaphragm provided on the anode chamber 5 side and the diaphragm provided on the cathode chamber 6 side. Become neutral or alkaline. In the present embodiment, the diaphragm 7 provided on the anode chamber 5 side and the diaphragm 9 provided on the cathode chamber 6 side are selected in such a combination that the inside of the intermediate chamber 4 becomes neutral to slightly acidic. This is because if the salt water in the intermediate chamber 4 shows alkalinity, magnesium, calcium or the like may be deposited as a scale and hinder the function of the electrolytic cell.

Above the inner surface of the salt water tank 3, a return port 14, a supply port 15, and a discharge port 16 are provided.
The return port 14 is an opening connected to a pipe (return path 17) provided between the intermediate chamber 4 and the salt water tank 3, and serves as a part for returning the solution in the intermediate chamber 4 into the salt water tank 3.
The replenishment port 15 is an opening connected to a pipe (replenishment path 31) provided between the raw water introduction part 19 and the salt water tank 3, and serves as a part for allowing a part of the raw water to flow into the salt water tank 3. A pump P <b> 2 is arranged in the middle of the pipe constituting the replenishment path 31, and replenishment water (raw water) is sent to the salt water tank 3 by the operation of the pump P <b> 2 based on the control of the control means 20.
The discharge port 16 is an opening provided on the inner surface of the salt water tank 3, and is an opening connected to a drain pipe (not shown) for discarding the solution. When the liquid level reaches the discharge port 16, the discharge port 16 is exceeded. The solution is discarded. That is, the salt water tank 3 functions as an overflow tank that keeps the water level below a certain level by providing the discharge port 16.

  The electrolyzed water generating apparatus 30 shown in FIG. 13 has the same operations and effects as the electrolyzed water generating apparatus 1 according to the above-described embodiment, and the means described in Examples 1 and 2 are applied. Similar actions and effects can be obtained.

  The present invention can be used in an electrolyzed water generating apparatus that electrolyzes salt water to generate electrolyzed water.

It is a schematic diagram showing the electrolyzed water generating apparatus. It is explanatory drawing showing an example of the salt water tank. It is a graph showing the relationship between salt concentration (saturation degree) and the voltage between electrode plates. It is the table | surface showing the relationship between the flow volume of makeup water, and the water level in a salt water tank. It is a graph for demonstrating the minimum circulation amount of circulating water. FIG. 3 is an operation timing chart of makeup water and circulating water according to the first embodiment, and an explanatory diagram showing a relationship between the voltage between the electrode plates and the current value. FIG. 6 is an operation timing chart of makeup water and circulating water according to the second embodiment, and an explanatory diagram showing a relationship between an electrode plate voltage and a current value. It is a graph showing the relationship between the operation time of a pump, and a discharge flow rate. It is a bar graph showing the relationship between the salt water circulation amount and the chlorine concentration in the salt water tank. It is a bar graph showing the relationship between makeup water and salt consumption. It is a line graph showing the relationship between makeup water and salt consumption. It is explanatory drawing showing the relationship between the operation timing chart of supplementary water and circulating water based on Example 2 which concerns on another control method, and the voltage between electrode plates and current value in connection therewith. 6 is a schematic diagram illustrating an electrolyzed water generating apparatus according to Example 3. FIG. It is explanatory drawing of the conventional 2 chamber type electrolytic cell.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrolyzed water production | generation apparatus 2 Electrolyzer 3 Salt water tank 4 Intermediate chamber 5 Anode chamber 6 Cathode chamber 7 Diaphragm 8 Anode plate 9 Diaphragm 10 Cathode plate 11 Salt water discharge port 12 Supply path 13 Filter 14 Return port 15 Supply port 16 Output port 17 Return Road 18 Supply path 19 Raw water introduction part 20 Control means

Claims (5)

An electrolytic cell comprising an intermediate chamber for circulating and supplying saline, an anode chamber adjacent to the intermediate chamber via a diaphragm and an anode, and a cathode chamber adjacent to the intermediate chamber via a diaphragm and a cathode;
A salt water tank that raises the concentration of the salt solution by bringing salt into contact with the salt solution that circulates and supplies the intermediate chamber;
A supply path for supplying saline to the intermediate chamber from the salt water tank;
A return path for returning the salt water after electrolytic treatment from the intermediate chamber to the salt water tank;
A replenishment path for taking a portion of the alkaline water discharged from the cathode chamber into a salt water tank;
A discharge path for maintaining a constant water level in the salt water tank,
The said salt water tank provided the connection port with the said return path, a replenishment path, and a discharge path above the upper surface of the undissolved salt accumulated inside, The electrolyzed water generating apparatus characterized by the above-mentioned. An electrolytic cell comprising an intermediate chamber for circulating and supplying saline, an anode chamber adjacent to the intermediate chamber via a diaphragm and an anode, and a cathode chamber adjacent to the intermediate chamber via a diaphragm and a cathode;
A salt water tank that raises the concentration of the salt solution by bringing salt into contact with the salt solution that circulates and supplies the intermediate chamber;
A supply path for supplying saline to the intermediate chamber from the salt water tank;
A return path for returning the salt water after electrolytic treatment from the intermediate chamber to the salt water tank;
A replenishment path for taking a part of the raw water supplied to the anode chamber and the cathode chamber into a salt water tank;
A discharge path for maintaining a constant water level in the salt water tank,
The said salt water tank provided the connection port with the said return path, a replenishment path, and a discharge path above the upper surface of the undissolved salt accumulated inside, The electrolyzed water generating apparatus characterized by the above-mentioned.   3. The electrolyzed water generating device according to claim 1, wherein the salt water tank is provided with a connection port with a replenishment path above a connection port with a discharge path. An intermediate chamber that circulates and supplies saline, an anode chamber that is adjacent to the intermediate chamber via a diaphragm and an anode, an electrolytic cell that includes a cathode chamber that is adjacent to the intermediate chamber via a diaphragm and a cathode, and sodium chloride and the intermediate chamber A method for generating electrolyzed water in an electrolyzed water generating apparatus having a salt water tank that increases the concentration of the saline by bringing the saline into circulation with the solution,
The reduced amount of the solution in the salt water tank, which is reduced by electrolysis, is supplemented with part of the alkaline water discharged from the cathode chamber as make-up water, and the excess of the make-up water supplied in excess is salt water connected to the discharge path. A method for producing electrolyzed water, characterized in that it is discarded from a connection port of a tank.   The method for producing electrolyzed water according to claim 4, wherein the amount of the makeup water is larger than the amount of solution in the salt water tank that actually decreases and is seven times or less of the amount of the solution.