JP4533731B2 - Electrolyzed water for alkaline cleaning, its production method and production device - Google Patents

Description

  The present invention relates to an electrolyzed water for alkaline cleaning suitable for use in general cleaning fields, in particular, cleaning of industrial parts and business cleaning, and a method and apparatus for generating the same.

  In the industrial cleaning field, hydrocarbon-based cleaning agents and surfactants that are the mainstream of water-based detergents are used in various fields as alternative cleaning agents for organic chlorine compounds and chlorofluorocarbons. However, hydrocarbon-based cleaning agents have problems in terms of flammability and working environment, and surfactants are difficult to treat wastewater, so it is said that aftertreatment becomes treated as industrial waste. Yes.

  Also, in the field of commercial cleaning, drainage facilities are not fully equipped in supermarkets and building floors that normally perform cleaning work, and the drainage after cleaning often flows directly into gutters for rainwater. For this reason, wastewater contamination by surfactants often used as cleaning agents has become a problem. In addition, surfactants are left behind due to lack of rinsing and the associated re-contamination problems are also surfaced.

  Therefore, in order to solve the above-mentioned problems in the industrial cleaning field and the industrial cleaning field, so-called alkaline electrolyzed water that has recently been generated from the cathode side of diaphragm membrane electrolysis using inorganic salts as a main raw material has attracted attention. ing. That is, generally, dirt components such as fats and oils and particle dirt are preferably washed in an alkaline aqueous solution containing dissolved hydrogen, as seen in Patent Document 1, so that sodium chloride, potassium chloride, carbonate Alkaline electrolyzed water (cathode water) obtained by electrolyzing an electrolyte such as potassium is used as a cleaning agent, and particularly iron is known to hardly corrode in the alkaline region. Alkaline electrolyzed water was considered suitable for cleaning.

On the other hand, as a method of automatically dissolving the electrolyte in raw water (tap water, etc.), it is preferable to use the saturated solubility of the substance. Therefore, a filter is set in the lower part, and the tap water previously placed in the container is used. A method is used in which an aqueous solution corresponding to the saturated solubility number of the substance is automatically generated from the filter by introducing a substance having a saturated solubility in water to a saturation concentration or higher. . Patent Document 2 describes the superiority of sodium chloride and potassium carbonate with respect to the difference in solubility accompanying temperature change, which is important when used as an electrolyte.
JP 2003-340451 A JP 2003-103261 A

  However, alkaline electrolyzed water (electrolytic cleaning water) produced by electrolysis using sodium chloride or potassium carbonate as an electrolyte has various problems as described below.

(A) Corrosion problem When iron is washed with alkaline electrolyzed water, as seen in (Data 1) shown in FIG. 1, due to the influence of chlorine ions contained in the alkaline electrolyzed water produced using sodium chloride as an electrolyte, It was confirmed that it would corrode. Therefore, in the invention described in Patent Document 2, it has been confirmed that it is preferable to use alkaline electrolyzed water (cathode water) obtained by electrolysis using potassium carbonate which is difficult to corrode metal as described above. On the other hand, non-ferrous metals such as aluminum and aluminum alloys have the property that they are easily corroded in the alkaline region. For these metals, neutral to weak alkaline alkaline electrolyzed water (anode It was confirmed by the application of Japanese Patent Application No. 2003-288379 by the present applicant that water) should be used as a cleaning agent.

  However, in the invention described in Patent Document 1, it has been confirmed that many particle stains are more effective as the pH is higher, and the anodic water has a detergency against particle stains adhering to aluminum or aluminum alloy. There was a problem of shortage. From such a situation, it is desirable to produce alkaline electrolyzed water having a high pH that does not corrode non-ferrous metals such as aluminum and aluminum alloys, and can effectively clean oil stains as well as particle stains. I came up with an idea.

(B) Problem of heat of dissolution When the above-mentioned potassium carbonate is used as the electrolyte, the solubility of potassium carbonate has the advantage of less fluctuation due to temperature change, while the heat of dissolution is very large. When used, the temperature inside the tank may become high immediately after the potassium carbonate is added due to the heat of dissolution. When the temperature in the tank becomes high, there is a problem that parts deteriorate rapidly and the generator does not operate normally. Further, as a countermeasure, it is necessary to select parts and materials that can withstand high temperatures. However, the use of heat-resistant parts further increases the cost. Furthermore, there is a concern that the saturated solution sent to the inside of the hose or the pipe in a high temperature state is recrystallized due to the liquid movement or the temperature decrease with time, and the hose or the pipe is blocked.

(C) Problems of reduced cleaning effect due to metal ions in tap water Generally, electrolyzed water often uses tap water as raw water, but tap water contains many areas where metal ions such as calcium and magnesium are included. It is known. In addition, these metal ions are known to halve the cleaning effect, and generally available cleaning agents include chelating agents such as phosphoric acid and EDTA, which have a function of sequestering metal ions (chelating effect), and edet. Mixing with water softening agents such as acid and aluminosilicate prevents the cleaning effect by metal ions from being halved. By the way, an environmental problem is mentioned as a great necessity to use electrolyzed water for cleaning purposes. Chelating agents and water softening agents are known as substances that have an adverse effect on the environment, like surfactants, and the use of these harmful substances in electrolyzed water is not preferable in view of the effects on the environment. Therefore, there is a problem that it is necessary to install a water softener as a means for removing metal ions such as calcium and magnesium.

(D) Problem of blockage of piping and the like due to generation of scale It is known that when there are many metal ions such as calcium and magnesium, it becomes a scale when generating alkaline electrolyzed water. Scales precipitate on the alkaline side and dissolve on the acidic side. When sodium chloride, which is originally neutral in pH, is used as the electrolyte, the scale adheres to the pipe or the part (secondary side) through which alkaline electrolyzed water passes after electrolysis. However, in the electrolysis of sodium chloride, acidic electrolyzed water is generated at the same time as alkaline electrolyzed water is generated. Therefore, the scale attached to the pipes and parts through which alkaline electrolyzed water passes dissolves due to the flow of acidic electrolyzed water due to polarity reversal. As a result, the scale is difficult to adhere. However, when potassium carbonate is used as the electrolyte, the pH of the potassium carbonate itself is alkaline, so that the scale adheres not only to the secondary side but also to pipes and parts (primary side) before electrolysis. In addition, when potassium carbonate is electrolyzed, alkaline electrolyzed water is generated from the cathode side, and at the same time, neutral to weakly alkaline electrolyzed water is generated from the anode side. It is not melted, and the amount of scale adhesion increases, eventually causing the problem that the piping is blocked and does not operate normally. Therefore, when potassium carbonate is used as an electrolyte, a water softener is essential as compared with salt.

(E) Increase in evaporation residue Since sodium metasilicate has lower electrical conductivity than sodium chloride or potassium carbonate, it is necessary to increase the concentration of tap water or pure water to give a certain amount of electricity. is there. However, the concentration in the alkaline electrolyzed water produced increases as the added concentration increases, resulting in a problem that the evaporation residue increases. If the evaporation residue increases, the crystallized substance is deposited on the surface of the cleaning workpiece, which causes problems such as adversely affecting the subsequent process and requiring rinsing with ion-exchanged water. Moreover, since sodium metasilicate is an alkaline substance, the pH of the anode water produced | generated in the state with a high addition density | concentration also shows alkalinity, and the problem that pH adjustment at the time of drainage becomes difficult arises.

  The present invention was developed in order to solve the problems described in the above (A) to (E), and the technical problem is not related to the metal species such as iron, aluminum or aluminum alloy. There is no worry of corrosion even when cleaning metals, etc., and the melting heat generated when dissolving the electrolyte can be absorbed, and the addition of a chelating agent and the installation of a water softener are not required. It is an object to provide an alkaline cleaning electrolyzed water that can reduce the amount of scale adhered to the surface and prevent an increase in evaporation residue, and a method and apparatus for producing the same.

(1) In order to solve the above technical problem, the alkaline cleaning electrolyzed water according to claim 1 of the present invention comprises sodium metasilicate or orthosilicate as an electrolyte with respect to raw water composed of tap water or pure water. The added aqueous solution is electrolyzed in a diaphragm electrolytic cell in which a diaphragm exists between the positive and negative electrodes, and is electrolyzed for alkaline cleaning on the cathode side. -80 mS / m (milli Siemens per meter) and 0.04 to 0.3 C / ml (coulomb per milliliter) between the positive and negative electrodes of the electrolytic cell. It is characterized by that.

(2) The method for producing alkaline cleaning electrolyzed water according to claim 2 of the present invention is to use an aqueous solution obtained by adding sodium metasilicate or sodium orthosilicate as an electrolyte to raw water comprising tap water or pure water. A method for generating alkaline cleaning electrolyzed water generated on the cathode side by electrolysis in a diaphragm electrolytic cell in which a diaphragm exists between the negative electrode and the negative electrode, wherein the electric conductivity of the aqueous solution is 20 to 80 mS / m It is characterized by producing by adding 0.04 to 0.3 C / ml of electric quantity between the positive and negative electrodes of the electrolytic cell.

(3) Moreover, the apparatus for producing alkaline electrolysis water according to claim 3 of the present invention uses an aqueous solution obtained by adding sodium metasilicate or sodium orthosilicate as an electrolyte to raw water composed of tap water or pure water. An electrolysis water generator for alkaline cleaning constructed to be generated on the cathode side by electrolysis in a diaphragm electrolytic cell in which a diaphragm exists between the cathode and the cathode, and the flow rate of the raw water can be adjusted. The water amount control valve, the current variable portion that makes it possible to vary the amount of current flowing between the positive and negative electrodes of the electrolytic cell, and the electrolyte made of sodium metasilicate or sodium orthosilicate can be added to the raw water, and An electrolyte addition unit configured to adjust the addition amount, a flow rate detection unit for detecting a flow rate per unit time of raw water, and an electrical conductivity of an aqueous solution to which the electrolyte is added are detected. In accordance with each data of the flow rate of the raw water, the electrical conductivity and the current amount detected by each of the detection units, the electrical conductivity detection unit, the current amount detection unit for detecting the amount of current flowing between the positive and negative electrodes of the electrolytic cell, The water amount adjusting valve, the current variable portion and the electrolyte adding portion are set so that the electric conductivity of the aqueous solution is 20 to 80 mS / m and the amount of electricity flowing between the positive and negative electrodes is 0.04 to 0.3 C / ml. And a control unit for controlling

(4) Further, the alkaline cleaning electrolyzed water according to claim 4 of the present invention, which further refers to claim 3, adjusts the water amount control valve, the current variable part and the electrolyte addition part to the control part according to manual operation. And an input operation unit capable of adjusting the electric conductivity of the aqueous solution to 20 to 80 mS / m and the amount of electricity flowing between the positive and negative electrodes to 0.04 to 0.3 C / ml. It is characterized by.

  As described above, according to the present invention, sodium metasilicate or sodium orthosilicate is used as the electrolyte, and the concentration of the aqueous solution before electrolysis in an electrolytic cell having a diaphragm, that is, the electric conductivity is 20 to 80 mS. The amount of electricity required for electrolysis flowing between the positive and negative electrodes of the electrolytic cell is set to 0.04 to 0.3 C / ml, and electrolysis is performed in the electrolytic cell to generate on the cathode chamber side. Since the alkaline electrolyzed water to be used is used as the wash water, it is possible to provide an excellent electrolyzed water for washing.

  That is, according to the present invention, it is possible to generate alkaline cleaning electrolyzed water that does not cause recrystallization or piping clogging, and no corrosion occurs regardless of the metal species such as iron, aluminum, or aluminum alloy, and Therefore, it is possible to always stably produce a safe and suitable cleaning agent having a high cleaning effect. Furthermore, according to the present invention, it is possible to minimize the consumption of the electrolyte, and at the same time, it is possible to suppress the amount of evaporation residue remaining in the washed product after washing. Moreover, since it becomes possible to bring the pH of the anodic water close to the range of the drainage standard, drainage treatment becomes easy, and further, it is possible to demonstrate excellent advantages such as being able to be used as circulating water, It is particularly suitable for use in the entire cleaning field, in particular for cleaning industrial parts and business cleaning.

<Test water>
The test water used in the present invention was electrolyzed water (cathode water) produced on the cathode side by performing diaphragm membrane electrolysis using potassium carbonate, sodium chloride or sodium silicate as an electrolyte.
The pH of electrolyzed water (cathode water) produced on the cathode side by diaphragm membrane electrolysis under constant conditions using potassium carbonate or sodium chloride as an electrolyte was pH 11.7. When sodium silicate is used as an electrolyte, pH 11.7 electrolyzed water (cathode water) generated at the cathode side by diaphragm membrane electrolysis is provided by adjusting the addition concentration to 70 mS / m, giving an electric quantity of 0.3 C / ml. Test water was used.

<Corrosion of iron>
The determination of the degree of corrosion was expressed in mg (mdd) of the weight loss per day with respect to the surface area of 1 dm ² of the test piece by the method described in JIS K0100 (1990). 1 (data 1) shown in FIG. 1 was subjected to diaphragm membrane electrolysis using three types of electrolytes of sodium metasilicate / potassium carbonate / sodium chloride. As a result, it was found that the test water generated using sodium metasilicate is an aqueous solution that is unlikely to corrode similarly to the test water generated using potassium carbonate.

<Corrosion of aluminum and aluminum alloys, copper and copper alloys>
As a result of visual confirmation of corrosion of aluminum or aluminum alloy, as shown in (Data 2) shown in FIG. 2, highly alkaline electrolyzed water generated by diaphragm membrane electrolysis using sodium metasilicate and sodium orthosilicate as electrolytes Then, it turned out that corrosion is suppressed compared with the cathode water obtained by electrolyzing potassium carbonate and sodium chloride. Moreover, it turned out that it does not corrode at all with respect to copper or a copper alloy. From this data, using alkaline electrolyzed water produced by using sodium metasilicate or sodium orthosilicate as an electrolyte for cleaning non-ferrous metals, especially aluminum or aluminum alloys, is an effective means for cleaning without corroding aluminum or aluminum metal. It turned out to be.

  The corrosion test was performed by electrolyzing each electrolyte and using electrolyzed water generated on the alkali side as test water, immersing the test piece in test water for 5 minutes, and visually checking the degree of discoloration after pulling up. Corrosion judgment was evaluated in 10 stages, with 1 indicating no corrosion and 10 indicating corrosion.

<Heat of dissolution>
When the heat of dissolution of sodium metasilicate and potassium carbonate was confirmed, as shown in FIG. 3 (graph 1), it was found that when sodium metasilicate was used as an electrolyte, it absorbed heat during dissolution. Here, since the heat of dissolution of sodium metasilicate and potassium carbonate was compared, the heat of dissolution when each was adjusted to a concentration that completely melted (10%) was measured.

  In general, electrolyte solubility tends to increase with increasing temperature. If the solubility of sodium silicate is considered to be the same, the amount of dissolution is lower in the low-temperature state during dissolution compared to the room temperature state after the temperature rise seen over time, so it is observed when potassium carbonate is used as the electrolyte. The problems of recrystallization and pipe clogging are eliminated. In fact, when it was automatically dissolved by the above-described saturation dissolution apparatus, recrystallization and piping blockage observed when potassium carbonate was used as the electrolyte could not be confirmed.

<Chelating effect>
Data on detergency when using hard water and soft water is shown in (Data 3) shown in FIG. 4A and (Graph 2) shown in FIG. 4B. Judgment of detergency is made with model fouling in the same way as described in JIS K3362 (1998), and the amount of fouling α adhering to the model fouling before washing and adhering to the model fouling after washing. The cleaning rate X of each cleaning power determination aqueous solution was determined from the difference from the amount of staining β.

  “Hard” in (Data 3) and (Graph 2) means that hard water is used as raw water, and “soft” means that soft water is used as raw water. As an example, when sodium chloride is used as an electrolyte, it is understood that when hard water is used as raw water, the detergency is reduced to about 1/4 compared to when soft water is used. From this data, it can be confirmed that metal ions such as calcium and magnesium contained in the hard water are factors that inhibit the cleaning effect. Next, when sodium metasilicate was used for the electrolyte, it was found that the same cleaning effect was obtained regardless of the difference in raw water, and it was confirmed that sodium metasilicate had the effect of sequestering metal ions.

  From this point, using sodium metasilicate as an electrolyte enables effective cleaning without adding a chelating agent contained in a commercially available cleaning agent. Although the water softener was installed, it becomes more advantageous in terms of installation man-hours and costs by eliminating the necessity.

<Cleaning effect>
When the washing effect when sodium metasilicate was used as the electrolyte was confirmed, as shown in (Data 4) shown in FIG. 5 (A) and (Graph 3) shown in FIG. 5 (B), sodium metasilicate was used. The detergency of sodium orthosilicate was as good as or better than that of sodium chloride or potassium carbonate as an electrolyte.

  Further, regarding the electrolyzed water (cathode water) produced on the cathode side by diaphragm membrane electrolysis using sodium metasilicate as an electrolyte, the relationship between pH and detergency was investigated, and as shown in (graph 7) shown in FIG. Furthermore, it was confirmed that the detergency increased from the time when the pH exceeded 10 and that a high cleaning rate was stably obtained at pH 11 or higher.

<Scale generation amount>
Next, the amount of scale generated when various electrolytes were dissolved in hard water and alkaline electrolyzed water produced by diaphragm electrolysis was allowed to stand at room temperature for one day was confirmed. As a result, as shown in (Data 5) shown in FIG. 6 (A) and (Graph 4) shown in FIG. 6 (B), sodium metasilicate and sodium orthosilicate used potassium carbonate or sodium chloride. It was found that the amount of scale generated was small compared to the case. From this result, it was found that the use of sodium silicate as the electrolyte can reduce the scale generation and the amount of scale attached to the pipes and parts.

<Significance of electrolysis>
A comparison of the detergency with sodium metasilicate aqueous solution adjusted to the same pH as electrolyzed water (cathode water) produced on the cathode side by diaphragm membrane electrolysis using sodium metasilicate as an electrolyte is shown in FIG. As seen in -1), it was confirmed that the electrolyzed water had higher detergency.

  It is known that the pH of the cathode water and the anode water is determined by the amount of electricity. The relationship between the amount of electricity and pH when sodium metasilicate is used as the electrolyte is shown in FIG. 7 (graph 5). In FIG. 7 (graph 5), the X-axis quantity of electricity C / ml = 0 means that before electrolysis. For example, in the legend “Cathode pH 10.85” or “Anode pH 10.85”, when the amount of electricity C / ml = 0, it is the state of the sodium silicate aqueous solution before electrolysis, and the pH of the Y axis at that time is 10.85. It is.

  8 (graph 6) shows the relationship between the sodium metasilicate addition concentration before electrolysis and the pH of the sodium metasilicate aqueous solution before electrolysis. It can be seen that the pH of the aqueous solution is also lowered. That is, in (graph 5) shown in FIG. 7, a low pH when the amount of electricity C / ml = 0 means that the concentration of addition before electrolysis is also low. As shown in FIG. 7 (graph 5), when 0.3 C / ml or more is applied, the pH of the cathodic water becomes 11.6 or more regardless of the addition concentration before electrolysis, and thereafter it is almost flat. It could be confirmed. Moreover, when the cleaning effect of the cathodic water generated when an amount of electricity of 0.3 C / ml was applied was confirmed, it was also shown in FIG. 1 (graph 7-2) that there was no difference in the cleaning effect. . Further, as described above, a stable cleaning effect can be obtained with cathodic water having a pH of 11 or higher, but it is necessary to set it to 0.04 Cml or more to obtain cathodic water having a pH of 11 or higher as shown in FIG. (Graph 5).

  On the other hand, from the graph 5 shown in FIG. 7, it can be confirmed that the pH of the anodic water is lower as the addition concentration before electrolysis is lower and the amount of electricity is higher, and can approach the drainage standard. It was. Moreover, when the addition concentration before electrolysis is increased, the pH of the sodium metasilicate aqueous solution before electrolysis becomes high as seen in (graph 6) shown in FIG. 8, and the generated electrolyzed water (cathode water). It is generally known that the evaporation residue increases, so it is not preferable to increase the concentration of addition. Furthermore, as shown in FIG. 10 (graph 7-1), electrolysis at the same pH shows a higher cleaning effect, so electrolyzed water (cathode water) having a pH of 11 or more is obtained by electrolysis. Needs to have a pH of less than 11 before electrolysis.

  Therefore, from the graph 6 shown in FIG. 8, it was concluded that it is preferable that the upper limit of the concentration of addition before electrolysis, in which the pH before electrolysis is less than 11, is 80 mS / m or less. Further, in order to stably obtain an electric quantity of 0.04 C / ml, it is possible to set the additive concentration (electric conductivity) to 20 mS / m or more as seen in (Graph 8) shown in FIG. I found it necessary.

  Next, the construction of the alkaline cleaning electrolyzed water generating apparatus according to the present invention will be described based on the description of FIG. 13. In the figure, 1 is divided into an anode chamber 1 A and a cathode chamber 1 B by a diaphragm 2. 3 and 4 are electrodes inserted into the anode chamber 1A and the cathode chamber 1B. Acidic electrolyzed water is generated in the anode chamber 1A, and alkaline electrolyzed water is generated in the cathode chamber 1B. Generated.

  11 is a water supply pipe that feeds raw water such as tap water or pure water into the electrolytic cell 1, 12 and 13 are a water amount adjusting valve provided in the middle of the water supply pipe 11 and a flow rate detection sensor as a flow rate detection unit, and 15 is sodium metasilicate. Alternatively, an electrolyte tank 16 containing an electrolyte made of sodium orthosilicate, 16 is an electrolyte addition pump as an electrolyte addition section that can send the electrolyte in the electrolyte tank 15 through the addition pipe 17 to the water supply pipe 11 and add it to the raw water. , 14 is an electric conductivity detecting sensor as an electric conductivity detecting unit capable of detecting the electric conductivity of the aqueous solution (raw water) added with the electrolyte flowing in the water supply pipe 11, and 5A, 5B is added with an electrolyte. A water supply branch pipe capable of feeding the aqueous solution into the anode chamber 1A and the cathode chamber 1B of the electrolytic cell 1 is shown.

  Further, in FIG. 13, 6A and 6B are water collections for taking out the anode water generated by electrolysis in the anode chamber 1A and the cathode chamber 1B and the alkaline electrolyzed water (cathode water) as the alkaline cleaning electrolyzed water according to the present invention. A pipe, 9 is a power supply substrate for supplying power to the electrodes 3 and 4, 7 is a current sensor as a current amount detection unit for detecting the amount of current supplied to both electrodes 3 and 4, and 8 is the current amount. 1 shows a current variable circuit as a current variable unit that can be changed.

  Reference numeral 10 denotes a control board as a control unit, and 10T denotes an operation board as an input operation unit provided on the control board 10. The operation board 10T adjusts the electrical conductivity of the aqueous solution (raw water) to which the electrolyte is added. There is provided a conductivity adjustment dial 10A that is made possible and a current amount adjustment dial 10B that can adjust the amount of current to both the electrodes 3 and 4.

  In the memory (not shown) constituting the control board 10, the flow rate of raw water sent from the sensors 13, 14, 7 and the electrolyte according to the setting data obtained by operating the adjustment dials 10 </ b> A, 10 </ b> B. The electrical conductivity of the aqueous solution (raw water) added with the amount of water and the amount of current to each electrode 3, 4 are detected, and the water amount adjustment valve 12, the electrolyte addition pump 16 and the current variable circuit 8 are adjusted based on the detected data. The electrical conductivity of the aqueous solution can be adjusted to 20 to 80 mS / m, and the amount of electricity flowing between the positive and negative electrodes 3 and 4 can be adjusted to 0.04 to 0.3 C / ml. Wear is stored.

The table | surface which showed the data (data 1) regarding the corrosion test of iron. The table | surface which showed the data (data 2) regarding the corrosion test of a nonferrous metal. The graph showing the heat of dissolution of sodium metasilicate and potassium carbonate (Graph 1). (A) is a table showing data (data 3) related to cleaning test 1 when using hard water and soft water, and (B) is a graph (graph 2). (A) is the table | surface figure which showed the data (data 4) regarding the cleaning test 2 at the time of using sodium metasilicate as electrolyte, (B) is the graph (graph 3). (A) is a table | surface figure of the data (data 5) regarding the scale generation test at the time of using sodium metasilicate as electrolyte, (B) is the graph (graph 4). The graph which showed the relationship between the electric quantity at the time of using sodium metasilicate as an electrolyte, and pH (graph 5). The graph which showed the relationship between the sodium metasilicate addition density | concentration before electrolysis and the pH of the sodium silicate aqueous solution before electrolysis (graph 6). The graph which showed the relationship between the pH of the electrolyzed water produced | generated to the cathode side by diaphragm membrane electrolysis using sodium metasilicate as electrolyte, and a detergency (graph 7). The graph which compared the washing | cleaning effect with the electrolysis water which uses sodium metasilicate aqueous solution and sodium metasilicate as an electrolyte (graph 7-1). The graph which compared the washing | cleaning effect of the cathode water produced | generated when the amount of electricity of 0.3 C / ml was given (graph 7-2). The graph which showed the relationship between the amount of electricity and electrical conductivity (graph 8). The block diagram which showed an example of the electrolyzed water generating apparatus for alkaline washing | cleaning which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Separative membrane electrolytic cell 1A Anode chamber 1B Cathode chamber 3, 4 Electrode 7 Current sensor 8 Current variable circuit 9 Power supply board 10 Control board 10T Operation board 11 Raw water supply pipe 12 Water quantity adjustment valve 13 Flow rate detection sensor 14 Electrical conductivity detection sensor 15 Electrolyte tank 16 Electrolyte addition pump

Claims (4)

Cathode side by electrolyzing an aqueous solution in which sodium metasilicate or sodium orthosilicate is added as electrolyte to raw water consisting of tap water or pure water in a diaphragm electrolyzer having a diaphragm between the positive and negative electrodes Electrolyzed water for alkaline cleaning produced in
The electric conductivity of the aqueous solution is 20 to 80 mS / m (milli Siemens per meter) and 0.04 to 0.3 C / ml (coulomb per milliliter) between the positive and negative electrodes of the electrolytic cell. Electrolyzed water for alkaline cleaning generated by adding electricity. Cathode side by electrolyzing an aqueous solution in which sodium metasilicate or sodium orthosilicate is added as electrolyte to raw water consisting of tap water or pure water in a diaphragm electrolyzer having a diaphragm between the positive and negative electrodes A method for generating alkaline cleaning electrolyzed water generated in
It is produced by adjusting the electric conductivity of the aqueous solution to 20 to 80 mS / m and adding an electric amount of 0.04 to 0.3 C / ml to the positive and negative electrodes of the electrolytic cell. A method for producing electrolytic water for alkaline cleaning. Cathode side by electrolyzing an aqueous solution in which sodium metasilicate or sodium orthosilicate is added as electrolyte to raw water consisting of tap water or pure water in a diaphragm electrolyzer having a diaphragm between the positive and negative electrodes A device for generating alkaline cleaning electrolyzed water configured to generate in
A water volume control valve that allows the flow rate of the raw water to be adjusted;
A current variable section that makes it possible to vary the amount of current flowing between the positive and negative electrodes of the electrolytic cell;
An electrolyte addition unit configured to be able to add an electrolyte composed of sodium metasilicate or sodium orthosilicate to raw water, and to be able to adjust the addition amount,
A flow rate detector that detects the flow rate per unit time of raw water;
An electrical conductivity detector for detecting the electrical conductivity of the aqueous solution to which the electrolyte is added;
A current amount detector for detecting the amount of current flowing between the positive and negative electrodes of the electrolytic cell;
According to the data of the flow rate, electrical conductivity, and current amount of the raw water detected by each of the detection units, the electrical conductivity of the aqueous solution is set to 20-80 mS / m for the water amount control valve, the current variable unit, and the electrolyte addition unit, respectively. And a control unit that controls the amount of electricity flowing between the positive and negative electrodes to be 0.04 to 0.3 C / ml.   In the control unit, the water amount adjusting valve, the current variable unit, and the electrolyte adding unit are adjusted according to a manual operation so that the electric conductivity of the aqueous solution is 20 to 80 mS / m and the amount of electricity flowing between the positive and negative electrodes is 0. The apparatus for generating alkaline water for alkaline cleaning according to claim 3, further comprising an input operation unit that can be adjusted to 0.04 to 0.3 C / ml.

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