JP2008155186A - Method and apparatus for producing ozone water - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for producing ozone water, which can realize a contemplated effect with the use of a small amount of carbon dioxide without causing bubbling and, at the same time, can realize a stabler production of ozone water than in the case where ozone is dissolved in ultrapure water into which carbon dioxide has been injected. <P>SOLUTION: In a part on the downstream of ultrapure water in which carbonated water containing ozone dissolved therein has been dissolved, a predetermined amount of carbon dioxide is further dissolved in the ultrapure water. The amount of the carbon dioxide dissolved is regulated by a signal output from a carbon dioxide concentration measuring device 6, which comprises a specific resistance measuring device or a pH meter for measuring the electrical conductivity of ultrapure water and is disposed between the dissolution point and the point of use. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method and an apparatus for producing ozone water in which decomposition of ozone in running water is suppressed, and more particularly, ozone that has a high ozone concentration and can supply a stable concentration of ozone water in cleaning electronic materials. The present invention relates to a water production method and a production apparatus.

  Wet cleaning has been widely used to remove foreign substances from the surface of electronic materials such as silicon substrates for semiconductors. In recent years, ozone water with strong oxidizing power has been used for wet cleaning due to demands for simplification of cleaning processes and resource saving. It has come to be used.

  As such a method for producing ozone water, a method is known in which ozone generated by electrolysis of ultrapure water is dissolved in ultrapure water.

  In this method, dissolved ozone in ozone water decomposes over time and becomes oxygen gas, so it is difficult to transfer it by long-distance piping. For this reason, an apparatus for producing ozone water must be installed near the cleaning device. In addition, the design and layout of the cleaning device and the like are restricted, and there is a problem that a plurality of ozone water production apparatuses must be installed when it is necessary to supply ozone water to a plurality of use points.

As a method for suppressing the decomposition of ozone into oxygen, a method has been proposed in which carbon dioxide (CO2) is dissolved in ultrapure water in advance, and ozone is dissolved in ultrapure water in which this carbon dioxide is dissolved ( Patent Document 1).
In this method, an ozone dissolving device is installed in the ultrapure water supply line, and carbon dioxide gas is injected into the ultrapure water supply line before the ozone dissolving device. In addition, the ozone supplied to this ozone dissolution apparatus is a part of ultrapure water separated from the ultrapure water supply line by the preparative line, electrolyzed by the electrolyzer, and then separated by the gas-liquid separator. . The liquid phase of the gas-liquid separator and the electrode tank of the electrolyzer are connected by a pipe, and ultrapure water only consumed in the electrode tank of the electrolyzer is separated through the liquid phase of the gas-liquid separator. It is supplied from the intake line.

  However, such a conventional method for producing ozone water has the following problems.

  That is, in the electrolytic device of ultrapure water, carbonated water is electrolyzed, so ultrapure water in which ozone and carbon dioxide gas are dissolved is generated. At this time, ozone is 20% or less, usually 10% in a mixture of oxygen. Only a portion corresponding to the partial pressure of the mixed gas that is generated as a component included and includes oxygen and carbon dioxide is dissolved in the ultrapure water.

  That is, in the electrolysis of ultrapure water, the amount of dissolved ozone decreases when the concentration of carbon dioxide gas is increased. In particular, when dissolved to near saturation saturation (around pH 3.5), the bubbling effect caused by the generation of bubbles further increases the ozone concentration. There was a problem that the amount of dissolution of the metal would decrease. Carbon dioxide does not follow Henry's law precisely because it generates ions in water, but the amount of dissolved ozone surely decreases as the amount of dissolved carbon dioxide increases.

  On the other hand, the effect of suppressing the decomposition of ozone increases as the concentration of carbon dioxide increases, but as described above, the partial pressure of ozone decreases relatively when the concentration of carbon dioxide increases, and the amount of ozone dissolved due to the bubbling effect. There was a problem that would decrease.

  As described above, in the conventional method for producing stabilized ozone water by electrolysis of carbonated water, if the use point is at a distant position, the ozone stabilization effect by carbon dioxide gas is weakened and the ozone concentration is lowered. There was a problem.

  Also, even if the concentration of carbon dioxide in ultrapure water is increased during electrolysis, ozone is released as bubbles along with carbon dioxide due to the bubbling effect, which does not increase the ozone concentration in ultrapure water. There has been a problem that carbon dioxide gas becomes bubbles and adheres to an object to be processed such as a wafer.

  Carbon dioxide gas suppresses the decomposition of ozone, but it does not strictly follow Henry's law because it generates bicarbonate ions or carbonate ions in water. However, if it is present in large quantities, it reduces the partial pressure of ozone. As a result, the amount of ozone dissolved is reduced.

  The present inventor conducted research to solve such a conventional problem. As a result, carbon dioxide was injected into ultrapure water to be supplied to an electrolyzer for producing ozone water to electrolyze it, and it was separated from the ozone gas dissolver. It was found that a high concentration of stable ozone water can be supplied over a long distance by additionally injecting carbon dioxide gas into ultrapure water downstream.

  The present invention has been made to solve such a conventional problem, and does not increase the concentration of carbon dioxide during electrolysis, and is more stable than when ozone is dissolved in ultrapure water into which carbon dioxide has been injected. An object of the present invention is to provide a method for producing ozone water and a device for producing ozone water.

  In order to achieve the above object, the method for producing ozone water of the present invention electrolyzes carbon dioxide gas-containing water to generate ozone, and ozone and carbon dioxide from carbon dioxide gas-containing water containing ozone generated in the electrolysis step. Gas-liquid separation step for separating gas, and ozone for dissolving ozone and carbon dioxide separated from ultrapure water in the gas-liquid separation step in ultrapure water of an ultrapure water supply line substantially free of carbon dioxide A carbon dioxide gas dissolving step and a carbon dioxide gas concentration adjusting step for further dissolving a predetermined amount of carbon dioxide gas downstream in the ultra pure water that has passed through the ozone / carbon dioxide gas dissolving step.

  More specifically, the method for producing ozone water of the present invention includes a carbon dioxide gas dissolving step for dissolving carbon dioxide gas in ultra pure water flowing through the first ultra pure water supply line, and an ultra pure water in which the carbon dioxide gas is dissolved. An electrolysis step of supplying water to an electrolyzer to generate ozone by electrolysis, a gas-liquid separation step of separating ozone and carbon dioxide from ultrapure water containing ozone and carbon dioxide produced in the electrolysis step, and the gas-liquid separation Ozone / carbon dioxide dissolving step of dissolving ozone and carbon dioxide separated from ultrapure water in the step into ultrapure water substantially free of carbon dioxide flowing through the second ultrapure water supply line; And a carbon dioxide concentration adjusting step for further dissolving a predetermined amount of carbon dioxide in the downstream of the ultrapure water that has undergone the carbon dioxide dissolving step.

In order to carry out the method for producing ozone water of the present invention, an electrolysis apparatus for electrolyzing ultrapure water in which carbon dioxide gas is dissolved to generate ozone and carbon dioxide gas, and an ultrasonium containing ozone and carbon dioxide gas produced by the electrolysis apparatus. A gas-liquid separator that separates gas components from pure water; an ozone / carbon dioxide dissolver that dissolves ozone and carbon dioxide separated by the gas-liquid separator in ultrapure water flowing through the ultrapure water supply line; A carbon dioxide gas dissolving device for further dissolving carbon dioxide gas in ultra pure water that is arranged downstream of the ozone / carbon dioxide gas dissolving device of the ultra pure water supply line and flows through the ultra pure water supply line;
The carbon dioxide concentration measuring device for measuring the concentration of carbon dioxide in ultra pure water that is arranged downstream from the carbon dioxide dissolving device and flows through the ultra pure water supply line, and the output signal of the carbon dioxide concentration measuring device, An ozone water production apparatus having a carbon dioxide concentration control device for controlling the amount of carbon dioxide supplied to the carbon dioxide dissolving device is used.

  More specifically, the first ultrapure water supply line, the second ultrapure water supply line branched from the first ultrapure water supply line, and the ultrapure water flowing through the second ultrapure water supply line. A carbon dioxide dissolving means for dissolving carbon dioxide therein, an electrolysis device for producing ozone and carbon dioxide by electrolyzing ultrapure water in which carbon dioxide supplied from a second ultra pure water supply line is dissolved, and the electrolysis A gas-liquid separator that separates gaseous components from ultrapure water containing ozone and carbon dioxide generated by the apparatus; and ozone and carbon dioxide separated by the gas-liquid separator are secondly supplied to the first ultrapure water supply line. An ozone / carbon dioxide dissolving device for dissolving in ultrapure water flowing through the first ultrapure water supply line downstream from the branch point with the ultrapure water supply line, and the ozone / carbonic acid in the first ultrapure water supply line First ultrapure water supply line arranged downstream from the gas dissolving device A carbon dioxide gas dissolving device that further dissolves carbon dioxide gas in the flowing ultra pure water, and an ultra flow that is arranged downstream of the carbon dioxide gas dissolving device of the first ultra pure water supply line and flows through the first ultra pure water supply line A carbon dioxide concentration measuring device for measuring the concentration of carbon dioxide in pure water, and a carbon dioxide concentration control device for controlling the amount of carbon dioxide supplied to the carbon dioxide dissolving device based on an output signal of the carbon dioxide concentration measuring device. An ozone water production apparatus characterized by having the following is advantageously used.

  The ultrapure water that passes through the first ultrapure water supply line has a specific resistance value of 18.2 MΩcm or more, a TOC concentration of 1 ppb or less, a metal impurity of 10 ppt or less, silica: 0.1 ppb or less, and a fine particle size of 0.05 μm. A high purity of about 1 to 2 / ml is suitable.

  As the carbon dioxide dissolving means for dissolving carbon dioxide in the first ultrapure water supply line, an ejector, a hollow fiber membrane device made of PTFE, or the like can be used.

  As an electrolysis apparatus used in the present invention, for example, an electrolysis ozone water production apparatus sold by Core Technology Co., Ltd. can be used. This electrolytic ozone water production apparatus can generate ozone and oxygen at the anode by the following reaction to generate ozone water having an ozone concentration of 14 to 20% by weight, but it is actually dissolved in ultrapure water. Excess 10% by weight is exhausted from the ozone gas dissolving device.

  Further, as an ozone / carbon dioxide dissolving device for dissolving ozone and carbon dioxide in the second ultrapure water supply line, for example, a hollow fiber membrane device made of PTFE is suitable. The hollow fiber membrane device made of PTFE can dissolve both ozone and carbon dioxide gas in ultrapure water. Thus, the method of dissolving carbon dioxide and ozone simultaneously through the PTFE membrane is more effective than the case of separately dissolving carbon dioxide and ozone, and the configuration of the apparatus can be simplified. Is suitable.

  The carbon dioxide concentration of ultrapure water in which carbon dioxide is dissolved in the present invention can be measured with a specific resistance measuring instrument or a pH meter.

  Incidentally, the carbon dioxide concentration of ultrapure water and the specific resistance value have a correlation as shown in FIG. 2, and the specific resistance and pH value of ultrapure water in which carbon dioxide gas is dissolved have a relationship as shown in FIG. It is in.

  Thus, the concentration of carbon dioxide gas in ultrapure water and the specific resistance are correlated, and the saturation solubility of carbon dioxide gas is much higher than the target range of the present invention. For example, from the relationship shown in FIG. When the flow rate of pure water is constant, measure the specific resistance of ultrapure water and control the amount of carbon dioxide supplied so that it reaches a predetermined value. Can be dissolved.

  The desirable carbon dioxide concentration of ultrapure water in which ozone gas is dissolved in the present invention is 3.8 to 4.5, preferably 4.0 to 4.4 in terms of pH. If it is high, the solubility of ozone is low.

  According to the present invention, even if the point of use is at a position away from the ozone dissolving device, carbon dioxide gas is additionally dissolved in the ozone water along the way, so that the ozone stabilization effect by the carbon dioxide gas is maintained and ozone water is used. No loss of function.

  Hereinafter, an embodiment of the present invention will be described.

  FIG. 1 shows an ozone water production apparatus according to an embodiment of the present invention. This ozone water production apparatus supplies a first ultra-pure water for ozone water that contains substantially no carbon dioxide gas. A pure water supply line 1, an electrolyzer 2 for producing ozone water, a second ultrapure water supply line 3 that branches from the first ultrapure water supply line and supplies ultrapure water to the electrolyzer 2; First and second carbon dioxide gas supply lines 4 and 5 for supplying carbon dioxide gas to the second ultra pure water supply line 3 and the first ultra pure water supply line 1 downstream, and the first ultra pure water supply line A carbon dioxide concentration measuring device 6 for measuring the carbon dioxide concentration of ultrapure water as pH or conductivity downstream from the carbon dioxide injection point 5p by the first second carbon dioxide supply line 5, and an output of the carbon dioxide concentration measuring device 6 The amount of carbon dioxide injection to the first ultrapure water supply line 1 is fed by the signal. And a carbon dioxide injection rate control device 7 for back control.

  A predetermined amount of carbon dioxide gas is supplied / dissolved from the first carbon dioxide supply line 4 via the carbon dioxide dissolving device 8 to the ultra pure water flowing through the second ultra pure water supply line 3. The carbon dioxide gas dissolving device 8 is supplied with ultrapure water on one side through a membrane and carbon dioxide gas on the other side, and the carbon dioxide gas is dissolved in the ultrapure water through the membrane. Ultrapure water (carbonated water) in which carbon dioxide gas is dissolved is supplied to the electrolyzer 2 driven by the DC power supply 9.

  An ion exchange membrane 2a is disposed in an electrolytic gas (ozone, oxygen, hydrogen) generation portion of the electrolysis apparatus 2, and a porous anode material 2b and a cathode material 2c are disposed in close contact with both surfaces of the ion exchange membrane 2a, respectively. The supplied ultrapure water is electrolyzed using the ion exchange membrane 2a as a solid electrolyte to generate a mixed gas of ozone and oxygen on the cathode side and hydrogen gas on the cathode side.

  The hydrogen gas generated on the cathode side is separated into a gas and a liquid (mist) by the gas-liquid separator 10 and is discharged through the hydrogen gas supply pipe 11. If necessary, this hydrogen gas can be supplied as fuel to a fuel cell (not shown) and recovered as electric power.

  The mixed gas of ozone and oxygen generated on the anode side is separated into a gas and a liquid (mist) by the gas-liquid separation device 12 and sent to the ozone gas dissolving device 14 by the air supply pipe 13. Note that the mixed gas of ozone and oxygen generated on the anode side contains carbon dioxide gas released from ultrapure water.

  The ozone gas dissolving device 14 is supplied with ultrapure water substantially free of carbon dioxide gas from the first ultrapure water supply line 1, and the mixed gas of ozone, oxygen, and carbon dioxide gas generated by the electrolysis device 2 is Here, ozone gas and oxygen gas dissolved in the ultrapure water but not dissolved are discharged from the exhaust pipe 15. The ozone gas dissolving device 14 has a mixed gas of ozone, oxygen, and carbon dioxide gas separated by the gas-liquid separation device 12 through the membrane, and the other from the first ultrapure water supply line 1 through the membrane. Ultrapure water is supplied, and the mixed gas permeates the membrane and dissolves in the ultrapure water.

  In the ultrapure water of the first ultrapure water supply line 1 in which the mixed gas of ozone, oxygen, and carbon dioxide gas is dissolved, the second carbon dioxide gas supply line 5 to the carbon dioxide gas dissolver 17 is disposed downstream of the ozone gas dissolver 14. Carbon dioxide is injected and dissolved via

  In the ultrapure water in which carbon dioxide gas is dissolved by the carbon dioxide gas dissolving device 16, the amount of dissolved carbon gas is measured by the carbon dioxide concentration measuring device 6 comprising a specific resistance measuring device or a pH measuring device. A carbon dioxide flow rate control valve 17 provided in the second carbon dioxide supply line 5 is controlled. That is, when the carbon dioxide gas amount is higher than the set value, the carbon dioxide flow rate control valve 17 is throttled, and when the carbon dioxide gas amount is lower than the set value, the carbon dioxide gas flow rate control valve 18 is opened and the carbon dioxide gas in the ultrapure water is opened. The gas concentration is controlled to be in a certain concentration range.

  The ultrapure water in which the ozone gas and the carbon dioxide gas thus produced are dissolved is measured by the ozone concentration meter 18 and supplied to a downstream use point.

Next, an embodiment of the present invention will be described.
(Example 1)
The ozone water production apparatus used in this example simulates the apparatus shown in FIG. 1, and the ultrapure water used and the experimental conditions are as follows.

That is, the ultrapure water has a specific resistance value of 18.0 MΩcm or more (20 ° C., TOC concentration: 1 ppb or less, metal impurities: 10 ppt or less, silica: 0.1 ppb or less, fine particles: 0.05 μm, size 1 to 2 / ml. )It was used. The flow rate in the second ultrapure water supply line 3 of this ultrapure water is 10 L / min, and the pressure at the inlet of the electrolyzer 2 is 0.2 kg / cm ² .

  Further, the ozone gas dissolving device 14 and the carbon dioxide gas dissolving device 16 were connected with a PFA tube 1/2 size of 50 m.

  In addition, as the electrolysis apparatus 2, an electrolysis apparatus manufactured by Core Technology Co., Ltd. is used, a simple PTFE ejector is used as the carbon dioxide gas dissolving apparatuses 8 and 17, and a PTFE hollow fiber membrane apparatus is used as the ozone gas dissolving apparatus 14. did.

  In addition to the ozone concentration meter 19, in addition to the ozone concentration meter 19, a 50 m PFA tube 1/2 size was connected to the outlet side of the ozone gas dissolving device 14, and another ozone water concentration meter was installed beyond that. (Not shown).

Next, the operation will be described.
In the ozone water production apparatus of this example, carbon dioxide gas was supplied to the first ultra pure water supply line 1 at a flow rate of 0.05 L / min, and carbon dioxide was supplied at a carbon dioxide (99.9% or higher) supply pressure of 1.0 kg. The solution was dissolved under the conditions of / cm ² (also effective at 0.8 kg / cm ² ), and ultrapure water in which the carbon dioxide gas was dissolved was supplied to the electrolysis apparatus 2. The ultrapure water in which the carbon dioxide gas is dissolved generates ozone by electrolysis in the electrolysis device 2 (ozone generation amount 12 g / hr), and the ultrapure water in which the generated ozone and carbon dioxide gas are dissolved is supplied to the gas-liquid separation device 12. The ozone and carbon dioxide gas (and oxygen) are separated, and the mixed gas of ozone and carbon dioxide gas is sent to the ozone gas dissolving device 14 and flows through the first ultrapure water supply line 1 at a pressure of 60 kPa and 1.5 L / min. It was dissolved in ultrapure water substantially free of carbon dioxide. In addition, the flow ratio of the ultrapure water in the second ultrapure water supply line 3 to the ultrapure water in the first ultrapure water supply line 1 is 0.05: 1.5 = 1: 30.

  Next, the ozone concentration of ultrapure water in which ozone and carbon dioxide in the first ultrapure water supply line (PFA tube) 1 were dissolved was measured 10 m downstream from the ozone gas dissolving device outlet.

Of the comparative examples shown below for comparison with the examples, in Comparative Example 1, carbon dioxide is dissolved in both ultrapure water flowing through the first and second ultrapure water supply lines. In the case where there was no carbon dioxide gas in the second ultrapure water supply line, a comparison was made when carbon dioxide was dissolved at a flow rate of ultrapure water of 1.5 l / min and a supply pressure of 1.0 kg / cm ^2. In Example 3, only the second ultrapure water supply line was dissolved under the conditions of a flow rate of ultrapure water of 1.5 l / min or less and carbon dioxide gas at a supply pressure of 1.0 kg / cm ² , and a part thereof was downstream. It is an example at the time of fractionating and flowing to the 1st ultrapure water supply line.

  In the state without the addition of carbonic acid in Comparative Example 1, the ozone water concentration was 30 mg / L, but when the water was fed a distance of 50 m after leaving the apparatus, the value changed between 3 and 8 mg / L, and the attenuation rate Was 81.7 ± 8.3%.

  In the example of Comparative Example 2, the ozone water concentration is dramatically improved to 60 mg / L, the ozone water concentration at 50 m ahead is between 45 to 52 mg / L, and the attenuation rate is 19.2 ± 5. Very stable at 8%.

  The ozone water of Comparative Example 2 has a pH of 5, and in the case of pH 5 from the graphs of FIGS. 3 and 4, the amount of dissolved carbon dioxide gas is about 10 mg / L, and thus the flow rate is 10 L / min. Then, the total injection amount of carbon dioxide gas is 100 mg / min.

  Incidentally, in the case of Example 1, since the measured pH is 4.3, the carbon dioxide gas injection amount at that time is about 260 mg / L, and the flow rate is 10 L / min. Therefore, the total injection amount is 2600 mg. / Min.

  Therefore, in order to set the ozone water of Comparative Example 2 to the same ozone amount as that of Example 1, it is necessary to inject a carbon dioxide amount of 2500 mg / L which is the difference, and the carbon dioxide gas actually corresponding to the shortage When 2500 mg / min was added, the concentration of ozone water was 58 mg / L.

  Since the theoretical saturation solubility of carbon dioxide is about 1,500 mg / L, the addition of carbon dioxide as in Example 1 does not saturate.

Thus, according to the Example of this invention, the ozone water density | concentration in 50m ahead changes between 53-57 mg / L, and an attenuation factor is 6 +/- 2.6%, A significant effect was observed.

The block diagram which shows the structure of one Example of this invention. The graph which shows the relationship between the carbon dioxide density in ultrapure water and specific resistance. The graph which shows the relationship between the specific resistance of ultrapure water which melt | dissolved the carbon dioxide gas, and pH. The graph which shows the amount of carbon dioxide dissolution required in order to make the ultrapure water of a predetermined flow volume into a fixed specific resistance.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... 1st ultrapure water supply line 2 ... Electrolyzer 2a ... Ion exchange membrane 2b ... Electrode anode 2c ... Electrode cathode 3 ... 2nd ultrapure water supply line 4 ... 1st carbon dioxide Supply line 5 …… Second carbon dioxide supply line 5P …… Carbon dioxide injection point 6 …… Carbon dioxide concentration measuring device 7… Carbon dioxide injection control device 8… Carbon dioxide melting device 9 …… DC power supply 10, 12 ... Gas-liquid separator 11 ... Hydrogen gas exhaust pipe 13 ... Air supply pipe 14 ... Ozone gas dissolving apparatus pipe 15 ... Exhaust pipe 16 ... Carbon dioxide gas dissolving apparatus 17 ... Carbon dioxide gas flow control valve 18 ... Ozone Water concentration meter

Claims (8)

An electrolysis process for producing ozone by electrolyzing water containing carbon dioxide;
A gas-liquid separation step of separating a gas component from carbon dioxide-containing water containing ozone generated in the electrolysis step;
An ozone / carbon dioxide gas dissolving step of dissolving the gas component separated from the ultrapure water in the gas-liquid separation step in ultrapure water of an ultrapure water supply line substantially free of carbon dioxide gas;
And a carbon dioxide concentration adjusting step of further dissolving a predetermined amount of carbon dioxide in the ultrapure water that has passed through the ozone / carbon dioxide dissolution step. A carbon dioxide gas dissolving step of dissolving carbon dioxide gas in ultra pure water flowing through a second ultra pure water supply line branched from the first ultra pure water supply line;
An electrolysis step of dissolving the carbon dioxide gas and supplying ultrapure water to an electrolyzer to generate ozone by electrolysis;
A gas-liquid separation step for separating gaseous components from ultrapure water containing ozone and carbon dioxide generated in the electrolysis step;
The ozone and carbon dioxide gas separated from the ultrapure water in the gas-liquid separation step is dissolved in ultrapure water flowing downstream from the branch point of the first ultrapure water supply line with the second ultrapure water supply line. Ozone and carbon dioxide gas dissolving process,
And a carbon dioxide concentration adjusting step of further dissolving a predetermined amount of carbon dioxide in the ultrapure water that has passed through the ozone / carbon dioxide dissolution step.   A carbon dioxide concentration measuring device is disposed between the point where the carbon dioxide gas is dissolved in the carbon dioxide concentration adjusting step and a use point, and the amount of carbon dioxide dissolved in the carbon dioxide concentration adjusting step is an output signal of the carbon dioxide concentration measuring device. The method for producing ozone water according to claim 1, wherein the ozone water is controlled by the method.   The ozone water according to any one of claims 1 to 3, wherein the measurement of the carbon dioxide concentration by the carbon dioxide concentration measuring device is performed by measuring the electric conductivity or pH of the ultrapure water to be measured. Manufacturing method.   The method for producing ozone water according to any one of claims 1 to 4, wherein the ozone and / or carbon dioxide gas is dissolved in the ultrapure water using an ejector or a membrane. An electrolyzer that generates ozone and carbon dioxide by electrolyzing ultrapure water in which carbon dioxide is dissolved;
A gas-liquid separator that separates gaseous components from ultrapure water containing ozone and carbon dioxide produced by the electrolyzer;
An ozone / carbon dioxide dissolving device for dissolving ozone and carbon dioxide separated in the gas-liquid separator in ultra pure water flowing through the ultra pure water supply line;
A carbon dioxide gas dissolving device for further dissolving carbon dioxide gas in ultra pure water that is arranged downstream of the ozone / carbon dioxide gas dissolving device of the ultra pure water supply line and flows through the ultra pure water supply line;
A carbon dioxide concentration measuring device for measuring the concentration of carbon dioxide in ultra pure water that is arranged downstream of the carbon dioxide dissolving device and flows through the ultra pure water supply line;
An apparatus for producing ozone water, comprising: a carbon dioxide concentration controller that controls a supply amount of carbon dioxide to the carbon dioxide dissolving device based on an output signal of the carbon dioxide concentration measuring device. A first ultrapure water supply line;
A second ultrapure water supply line branched from the first ultrapure water supply line;
Carbon dioxide dissolving means for dissolving carbon dioxide in ultra pure water flowing through the second ultra pure water supply line;
An electrolyzer that generates ozone and carbon dioxide by electrolyzing ultrapure water in which carbon dioxide supplied from a second ultrapure water supply line is dissolved;
A gas-liquid separator that separates gaseous components from ultrapure water containing ozone and carbon dioxide produced by the electrolyzer;
The ultrapure water that flows through the first ultrapure water supply line downstream of the branch point between the first ultrapure water supply line and the second ultrapure water supply line of ozone and carbon dioxide separated by the gas-liquid separator. Ozone / carbon dioxide dissolving device to be dissolved in,
A carbon dioxide gas dissolving device that is disposed downstream of the ozone / carbon dioxide gas dissolving device of the first ultra pure water supply line and further dissolves carbon dioxide gas in ultra pure water flowing through the first ultra pure water supply line;
A carbon dioxide concentration measuring device for measuring the concentration of carbon dioxide in ultrapure water that is arranged downstream of the carbon dioxide gas dissolving device in the first ultra pure water supply line and flows through the first ultra pure water supply line;
An apparatus for producing ozone water, comprising: a carbon dioxide concentration controller that controls a supply amount of carbon dioxide to the carbon dioxide dissolving device based on an output signal of the carbon dioxide concentration measuring device.   The apparatus for producing ozone water according to claim 6 or 7, wherein the carbon dioxide concentration measuring device is a specific resistance measuring device or a pH meter.

Images