JP2015180500A - Gas dissolved water supply device and manufacturing method of gas dissolved water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas dissolved water supply device capable of stably supplying gas dissolved water having low dissolved gas concentration (a low saturation degree), and to provide a manufacturing method of the gas dissolved water.SOLUTION: An oxygen gas is supplied from a gas supply pipe 31 to a gas phase chamber 13 and a vacuum pump 35 is operated to evacuate the gas phase chamber 13. Further, raw water is supplied from a raw water pipe 21 into a liquid phase chamber 12. A part of oxygen in the gas phase chamber 13 penetrates a gas transmission film 11 and dissolves in the raw water in the liquid phase chamber 12 to produce gas dissolved water. The other part of the oxygen in the gas phase chamber 13 is suctioned by the vacuum pump 35 with condensed water to be discharged from an exhaust pipe 33. Dissolved gas concentration of the gas dissolved water is measured by a dissolved gas concentration meter 23. Opening of a gas flow control valve 32 is adjusted so that the measured concentration becomes a target value.

Description

  The present invention relates to a gas-dissolved water supply device and a method for producing gas-dissolved water. Specifically, the present invention has a gas-permeable membrane module partitioned into a gas phase chamber and a liquid phase chamber by a gas permeable membrane, and the liquid phase chamber is covered with the gas-permeable membrane module. Treated water is passed and gas is supplied to the gas phase chamber, and the gas is dissolved from the gas phase chamber through the gas permeable membrane into the water to be treated in the liquid phase chamber. The present invention relates to a gas-dissolved water supply device that uses gas-dissolved water and a method for producing gas-dissolved water using the gas-dissolved water supply device.

  Conventionally, cleaning of a silicon substrate for a semiconductor, a glass substrate for a liquid crystal, etc., mainly includes a mixed solution of hydrogen peroxide solution and sulfuric acid, a mixed solution of hydrogen peroxide solution, hydrochloric acid and water, hydrogen peroxide solution, ammonia solution and water. This is performed by a so-called RCA cleaning method in which a concentrated chemical solution based on hydrogen peroxide, such as a mixed solution, is washed at a high temperature and then rinsed with ultrapure water. However, this RCA cleaning method uses a large amount of hydrogen peroxide water, high-concentration acid, alkali, etc., so the cost of the chemical solution is high. In addition, the cost of rinsing ultrapure water, the cost of waste liquid treatment, and chemical vapor are exhausted. However, a large cost is required, such as an air conditioning cost for newly preparing clean air.

  On the other hand, various efforts have been made to reduce costs in the cleaning process and reduce the burden on the environment. A typical example is a technique for cleaning an object to be processed by ultrasonic cleaning or the like using gas-dissolved water in which a specific gas is dissolved. As this specific gas, oxygen gas, ozone, carbon dioxide gas, rare gas, inert gas, hydrogen gas, or the like is used.

  As a method for producing such gas-dissolved water, a method using a membrane module incorporating a gas-permeable membrane is known. In this method, water is supplied to the liquid phase side of the gas permeable membrane, a specific gas is supplied to the gas phase side, and the gas on the gas phase side is dissolved in the water on the liquid phase side through the gas permeable membrane. Manufacturing gas-dissolved water.

  For example, Japanese Patent Application Laid-Open No. 11-077023 describes that after degassing ultrapure water to lower the saturation of dissolved gas, hydrogen gas is dissolved in this ultrapure water.

  FIG. 2 is a process flow diagram of the publication. The ultrapure water is sent to the deaeration membrane module 2 via the flow meter 1. In the degassing membrane module 2, the gas phase in contact with the ultrapure water through the gas permeable membrane is kept in a reduced pressure state by the vacuum pump 3, and the gas dissolved in the ultrapure water is degassed. The ultrapure water from which the dissolved gas has been degassed is then sent to the hydrogen gas dissolving membrane module 4. In the hydrogen gas dissolving membrane module 4, the hydrogen gas supplied from the hydrogen gas supplier 5 is sent to the gas phase side and supplied to ultrapure water through the gas permeable membrane. A chemical solution such as ammonia water is added from the chemical solution storage tank 6 to the ultrapure water in which the dissolved hydrogen gas concentration has reached a predetermined value by the chemical injection pump 7 and adjusted to a predetermined pH value. The hydrogen-containing ultrapure water that has become alkaline due to the dissolution of hydrogen gas is finally sent to the microfiltration device 8 and fine particles are removed by an MF filter or the like.

  The dissolved gas measurement sensors 9 installed at the inlet and outlet of the degassing membrane module 2 measure the amount of gas in the ultrapure water to determine the saturation, and send a signal to the vacuum pump to determine the saturation and the desired purity of the ultrapure water. The amount of deaeration is adjusted by comparing with the degree of saturation. The deaeration amount is adjusted, for example, by adjusting the degree of vacuum by the vacuum pump by adjusting the degree of opening of the vacuum degree adjusting valve. The gas saturation of the ultrapure water after deaeration is measured by the dissolved gas measuring sensor 9, and the hydrogen gas concentration in the hydrogen-containing ultrapure water flowing out from the hydrogen gas dissolving membrane module is measured by the dissolved hydrogen measuring sensor 9A. These measurement signals are sent to the hydrogen gas supply device, and the supply amount of the hydrogen gas is controlled by adjusting, for example, the opening degree of a valve provided in the hydrogen gas supply path.

JP-A-11-077023

  In the above-mentioned Japanese Patent Application Laid-Open No. 11-077023, the gas permeable membrane of the hydrogen gas dissolving membrane module 4 has a characteristic of allowing only gas to pass and not allowing liquid to pass through, and water vapor passes through this gas permeable membrane. For this reason, water vapor diffuses from the liquid phase chamber to the gas phase chamber through the gas permeable membrane, dew condensation in the gas phase chamber becomes condensed water, and accumulates in the gas phase chamber.

  Here, when producing gas-dissolved water having a low concentration (low saturation) with a dissolved gas concentration of the order of μg / L (ppb), the effects of minute fluctuations of various conditions, gas-dissolving membrane modules (FIG. 2) Due to the influence of the condensed water in the gas phase chamber of the hydrogen gas dissolving membrane module 4), it was difficult to stabilize the dissolved gas concentration in the gas dissolving water.

  Further, even in the case of producing gas-dissolved water having a dissolved gas concentration of the order of mg / L (ppm), such as carbon dioxide-dissolved water, the degassing level of raw water (degassing membrane module 2 in FIG. 2). If the degree of degassing due to (2) is high, condensed water tends to accumulate in the gas phase chamber of the gas dissolving membrane module (hydrogen gas dissolving membrane module 4 in FIG. 2), and the influence of the condensed water cannot be ignored. As in the case of producing the gas-dissolved water, it was difficult to stabilize the dissolved gas concentration in the gas-dissolved water.

  An object of the present invention is to provide a gas-dissolved water supply apparatus and a gas-dissolved water production method capable of stably supplying gas-dissolved water having a low dissolved gas concentration (low saturation). .

  The gas-dissolved water supply device of the present invention (Claim 1) has a gas permeable membrane module partitioned into a gas phase chamber and a liquid phase chamber by a gas permeable membrane, and water to be treated is supplied to the liquid phase chamber by a water flow means. Passing water, supplying gas to the gas phase chamber by gas supply means, and dissolving the gas from the gas phase chamber through the gas permeable membrane into the water to be treated in the liquid phase chamber, In the gas-dissolved water supply apparatus in which the water to be treated is gas-dissolved water, the vacuum is provided so that the gas is supplied into the gas phase chamber by the gas supply means while the gas chamber is evacuated by vacuum exhaust means. An exhaust means is provided.

  The gas-dissolved water supply device according to claim 2 is the gas-dissolved water supply device according to claim 1, wherein the dissolved gas concentration of the gas-dissolved water is measured, and the amount of gas supplied from the gas supply means is determined according to the measurement value of the measurement means. And control means for controlling the dissolved gas concentration by adjusting.

  According to a third aspect of the present invention, there is provided the gas-dissolved water supply device according to the first or second aspect, wherein a connection port with the vacuum evacuation means is provided at a lower portion of the gas phase chamber.

  According to a fourth aspect of the present invention, there is provided the gas-dissolved water supply device according to any one of the first to third aspects, wherein the gas contains oxygen.

  The gas-dissolved water supply device according to claim 5 is characterized in that, in claim 4, the dissolved gas concentration of the gas-dissolved water is 1/400 or less of the solubility of the gas.

  A gas-dissolved water supply device according to a sixth aspect is characterized in that the gas contains carbon dioxide in any one of the first to third aspects.

  The gas-dissolved water supply device according to claim 7 is characterized in that, in claim 6, the dissolved gas concentration of the gas-dissolved water is 1/50 or less of the solubility of the gas.

  The gas-dissolved water supply device according to claim 8 is characterized in that in any one of claims 1 to 3, the gas includes at least one of nitrogen, argon, ozone, hydrogen, clean air, and a rare gas. To do.

  A method for producing gas-dissolved water according to the present invention (invention 9) is a method for producing gas-dissolved water using the gas-dissolved water supply device according to any one of claims 1 to 8, wherein the liquid phase Water to be treated is passed through the chamber and gas is supplied to the gas phase chamber while evacuating the gas phase chamber, and the gas is supplied from the gas phase chamber through the gas permeable membrane to the liquid phase chamber. The water to be treated is gas-dissolved water by being dissolved in the water to be treated.

  In the gas-dissolved water supply apparatus (claim 1) and the gas-dissolved water production method (claim 9) of the present invention, the gas supply chamber is evacuated by the evacuation means, and the gas supply means The gas is supplied into the gas phase chamber. Thereby, it is possible to stably supply gas-dissolved water having a low dissolved gas concentration (low saturation).

  That is, conventionally, when condensed water accumulates in the gas phase chamber, the condensate draining process is performed. During this condensate draining process, pressure fluctuations occur in the gas phase chamber, and as a result gas dissolved water is discharged. Dissolved gas concentration varies. In the present invention, since the gas is supplied into the gas phase chamber while evacuating the gas phase chamber, the condensed water in the gas phase chamber is always discharged by the evacuation. Therefore, in the present invention, it is not necessary to separately perform the condensed water discharge step, and fluctuations in the dissolved gas concentration of the gas dissolved water caused by this condensed water discharge step are avoided. It is possible to supply stably.

  INDUSTRIAL APPLICABILITY The present invention can be used for a gas-dissolved water supply device that stably supplies low-concentration gas-dissolved water and a method for producing gas-dissolved water. Especially for the production of low concentration gas dissolved water with strictly controlled dissolved gas concentration and ultrapure water with strictly controlled dissolved gas concentration, which are used in cleaning processes in the semiconductor industry. It is suitable for application to a gas-dissolved water supply device and a method for producing gas-dissolved water.

  The dissolved gas concentration is measured by adjusting the dissolved gas concentration of the gas-dissolved water and the supply amount of the gas from the gas supply unit according to the measurement value of the measurement unit. It is preferable to have control means for controlling. Such feedback control makes it possible to supply gas-dissolved water having a stable dissolved gas concentration even in a low concentration region (low saturation region).

  If the connection port with the vacuum exhaust means is provided in the lower part of the gas phase chamber as in claim 3, the condensed water accumulated in the gas phase chamber can be efficiently discharged.

  As in claim 4, the gas may contain oxygen. In this case, as in claim 5, the dissolved gas concentration of the gas-dissolved water is preferably 1/400 or less of the solubility of the gas.

  As in claim 6, the gas may contain carbon dioxide. In this case, as in claim 7, the dissolved gas concentration of the gas-dissolved water is preferably 1/50 or less of the solubility of the gas.

  The gas may include at least one of nitrogen, argon, ozone, hydrogen, clean air, and a rare gas.

It is a systematic diagram of the gas dissolution water supply device concerning an embodiment. It is a manufacturing-process system diagram of the hydrogen-dissolved water which concerns on a prior art example.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram for explaining a gas-dissolved water supply device and a method for producing gas-dissolved water according to an embodiment.

  The raw water pipe 21 is connected to the lower part of the liquid phase chamber 11 of the gas permeable membrane module 10.

  The gas permeable membrane module 10 is partitioned into the liquid phase chamber 12 and the gas phase chamber 13 by a gas permeable membrane 11.

  A gas-dissolved water supply pipe 22 having a dissolved gas concentration meter 23 is connected to the upper part of the liquid phase chamber 12.

  One end of a gas supply pipe 31 having a gas flow rate control valve 32 is connected to the upper part of the gas phase chamber 13. The other end of the gas supply pipe 31 is connected to a gas source such as a gas cylinder. An exhaust pipe 33 including a pressure gauge 34 and a vacuum pump 35 is connected to the lower part of the gas phase chamber 13. The detection signal of the dissolved gas concentration meter 23 is input to the control device 24. The control device 24 controls the gas flow rate control valve 32 so that the detected concentration of the dissolved gas concentration meter 23 becomes the target concentration.

  As will be described later, the target gas is dissolved in the raw water passed through the raw water pipe 21 to produce a low-concentration (low saturation) gas-dissolved water. For this reason, as this raw water, the target gas to be dissolved is almost not dissolved and is not saturated with a gas other than the target gas, and the target gas can be dissolved without being oversaturated. It is preferable. Usually, deaerated water obtained by sufficiently degassing dissolved gas from ultrapure water or the like can be used. The deaeration can be performed using, for example, the deaeration membrane module 2 shown in FIG.

  The gas permeable membrane 10 is not particularly limited as long as it does not permeate water and permeates gas dissolved in water. For example, polypropylene, polydimethylsiloxane, polycarbonate-polydimethylsiloxane block copolymer, Examples thereof include a polymer film such as polyvinylphenol-polydimethylsiloxane-polysulfone block copolymer, poly (4-methylpentene-1), poly (2,6-dimethylphenylene oxide), and polytetrafluoroethylene.

  There is no restriction | limiting in the vacuum pump 35, A water seal type, a scroll type, etc. are used. However, those using oil for generating a vacuum are preferably oil-less because the oil may reversely diffuse and contaminate the gas permeable membrane 11.

  As the gas supplied from the gas supply pipe 31, oxygen, carbon dioxide, nitrogen, argon, ozone, hydrogen, clean air, a mixed gas of two or more of these gases, and the like are used.

  These gases may be diluted with a dilution gas. In that case, as the dilution gas, a rare gas such as argon or helium, an inert gas such as nitrogen, carbon dioxide gas, clean air, or a mixed gas of two or more of these gases is used.

  The gas flow rate control valve 32 is preferably oilless.

  Next, an example of a method for producing gas-dissolved water using the gas-dissolved water supply device of FIG. 1 will be described.

  In this example, oxygen is used as the gas, and the water temperature is 25 ° C. The solubility of oxygen in water at 25 ° C. and 1 atm is 40.9 mg / L.

  By opening the gas flow control valve 32, oxygen gas is supplied from the gas supply pipe 31 into the gas phase chamber 13, and the vacuum pump 35 is operated to evacuate the gas phase chamber 13 through the exhaust pipe 33. Exhaust. Further, raw water is supplied from the raw water pipe 21 into the liquid phase chamber 12.

  Here, the degree of vacuum in the gas phase chamber 13 needs to be higher than the degree of degassing of the raw water. Thereby, a part of the gas (oxygen) in the gas phase chamber 13 passes through the gas permeable membrane 11 and is dissolved in the raw water in the liquid phase chamber 12. The pressure in the gas phase chamber 13 is preferably −90 kPa or less, more preferably −90 to −97 kPa, and particularly preferably −93 to −96 kPa. When it is −90 kPa or less, the condensed water in the gas phase 13 can be discharged well.

  Part of the oxygen supplied from the gas supply pipe 31 into the gas phase chamber 13 passes through the gas permeable membrane 11 as described above and dissolves in the raw water in the liquid phase chamber 12. The gas dissolved water thus obtained flows out from the gas dissolved water supply pipe 22. The remainder of the oxygen supplied into the gas phase chamber 13 is sucked by the vacuum pump 35 together with water vapor that has passed through the gas permeable membrane 11 from the liquid phase chamber 12 side and condensed water obtained by condensing the water vapor. Thus, the gas is discharged from the exhaust pipe 33.

  The dissolved gas concentration in the gas dissolved water supply pipe 22 is measured by a dissolved gas concentration meter 23, and a measurement signal is input to the control device 24. The control device 24 controls the gas flow rate by adjusting the opening of the gas flow control valve 32 so that the dissolved oxygen concentration of the dissolved gas concentration meter 23 becomes a target value (or target range). By this feedback control, gas-dissolved water having a desired dissolved gas concentration is produced.

  The dissolved oxygen concentration in the gas-dissolved water is determined as appropriate according to the use of the gas-dissolved water. For example, when used as a low-concentration oxygen-dissolved water (cleaning water) in a cleaning process in the semiconductor industry field. The dissolved oxygen concentration is preferably about 1 to 100 μg / L, particularly about 10 to 60 μg / L.

  The flow rate of raw water in the raw water pipe 21 is, for example, about 2 to 10 L / min, and the flow rate of oxygen in the gas supply pipe 31 is, for example, about 0.1 to 10 mL / min.

  In the present embodiment, the condensed water in the gas phase chamber 13 is discharged by the vacuum pump 35, so that the condensed water is prevented from accumulating in the gas phase chamber 13. Therefore, the dissolved gas concentration fluctuation caused by the pressure fluctuation in the gas phase chamber 13 generated when the condensed water accumulated in the gas phase chamber 13 is discharged, or the condensed water in the gas phase chamber 13 is gasified. Variations in the dissolved gas concentration of the gas-dissolved water due to the partial penetration of the permeable membrane 12 are prevented. In particular, in this embodiment, since the drain pipe 33 is connected to the lower part of the gas phase chamber 13, it is possible to sufficiently prevent the condensed water from accumulating in the gas phase chamber 13.

  In the present embodiment, the dissolved gas concentration in which the dissolved gas concentration is in the low concentration region or the low saturation region can be stably produced by feedback control.

  The above embodiment is an example of the present invention, and the present invention is not limited to the above embodiment. The gas is not limited to oxygen. For example, carbon dioxide may be dissolved in raw water instead of oxygen. When this carbon dioxide-dissolved water is used in a cleaning process in the semiconductor industry field, the dissolved carbon dioxide concentration is preferably about 1 to 100 mg / L, particularly about 10 to 60 mg / L.

  Further, when nitrogen is dissolved in the raw water, for example, the dissolved gas concentration is preferably 1 to 50 μg / L, particularly 5 to 30 μg / L. In the case of argon, the dissolved gas concentration is preferably 1 to 100 μg / L, particularly 10 to 60 μg / L. In the case of ozone, the dissolved gas concentration is preferably 10 to 1000 μg / L, particularly 50 to 500 μg / L. In the case of hydrogen, the dissolved gas concentration is preferably 5 to 500 μg / L, particularly 10 to 100 μg / L. In the case of clean air, the dissolved gas concentration is preferably about 1 to 50 μg / L, particularly about 5 to 30 μg / L.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

  In addition, the apparatus of FIG. 1 was used as a gas dissolved water supply apparatus. The specifications and operating conditions of the gas permeable membrane module 10 and the dissolved gas concentration meter 23 are as follows.

Gas permeable membrane module: Gas dissolving membrane manufactured by Celgard (trade name: Liquicel)
Dissolved gas concentration meter: Dissolved oxygen meter manufactured by Hack Ultra Analytics Japan,
Model 3610
Volume of raw water delivered: 5L / min
Required dissolved oxygen concentration: 5 μg / L
Water temperature: 25 ° C

Example 1
The amount of oxygen gas supplied from the gas supply pipe 31 was controlled to 0.5 mL (standard state) / min by the gas flow rate control valve 32. Further, the gas phase chamber 13 was evacuated by the vacuum pump 35 so that the pressure in the gas phase chamber 13 became −97 kPa.

  As a result, the dissolved oxygen concentration in the obtained oxygen-dissolved water was continuously controlled to 5 μg / L ± 5% or less. Further, the condensed water does not accumulate in the gas phase chamber 13, and it is not necessary to separately perform the condensed water discharge operation.

Comparative Example 1
In the first embodiment, the vacuum pump 35 is normally stopped and the gas phase chamber 13 is not evacuated. When the condensed water accumulates in the gas phase chamber 13, the vacuum pump 35 is operated to condense water. Oxygen-dissolved water was produced in the same manner except that the discharging operation was performed.

  As a result, a concentration fluctuation of 5 μg / L ± 20% or more occurred in the dissolved oxygen concentration in the oxygen-dissolved water during the operation of discharging the condensed water, and it was difficult to stably supply the oxygen-dissolved water.

DESCRIPTION OF SYMBOLS 10 Deaeration membrane module 11 Gas permeable membrane 12 Liquid phase chamber 13 Gas phase chamber 21 Raw water piping 22 Gas dissolved water supply piping 23 Dissolved gas concentration meter 31 Gas supply piping 32 Gas flow control valve 33 Exhaust piping 34 Pressure gauge 35 Vacuum pump

The gas-dissolved water supply device of the present invention (Claim 1) is a device for producing a low-concentration gas-dissolved water having a dissolved gas concentration of the order of ppb, and is divided into a gas phase chamber and a liquid phase chamber by a gas permeable membrane. A gas permeable membrane module, water to be treated is passed to the liquid phase chamber by water passing means, gas is supplied to the gas phase chamber by gas supplying means, and the gas is supplied from the gas phase chamber to the gas phase chamber. The gas phase chamber is evacuated by vacuum evacuation means in a gas-dissolved water supply apparatus that uses the water to be treated as gas-dissolved water by dissolving in the water to be treated in the liquid-phase chamber through a gas permeable membrane. However , by supplying the gas into the gas phase chamber by the gas supply means, the gas-dissolved water supply device provided with the vacuum evacuation means so that the condensed water in the gas phase chamber is always discharged during the gas supply. In the lower part of the gas phase chamber. The connecting port between the exhaust means is provided and is characterized in.

According to a third aspect of the present invention, there is provided the gas-dissolved water supply device according to the first or second aspect , wherein the gas contains oxygen.

A gas-dissolved water supply device according to claim 4 is characterized in that, in claim 3 , the dissolved gas concentration of the gas-dissolved water is 1/400 or less of the solubility of the gas.

The gas-dissolved water supply device according to claim 5 is characterized in that, in claim 1 or 2 , the gas contains carbon dioxide gas.

The gas-dissolved water supply device according to claim 6 is characterized in that, in claim 5 , the dissolved gas concentration of the gas-dissolved water is 1/50 or less of the solubility of the gas.

Gas dissolved water supply system according to claim 7, in claim 1 or 2, wherein the gas is characterized nitrogen, argon, ozone, hydrogen, to include at least one of the clean air and a rare gas.

A method for producing gas-dissolved water according to the present invention (invention 8 ) is a method for producing gas-dissolved water using the gas-dissolved water supply device according to any one of claims 1 to 7 , wherein the liquid phase Water to be treated is passed through the chamber and gas is supplied to the gas phase chamber while evacuating the gas phase chamber, and the gas is supplied from the gas phase chamber through the gas permeable membrane to the liquid phase chamber. By dissolving in the water to be treated, the water to be treated is used as gas-dissolved water while constantly discharging condensed water in the gas phase chamber during the gas supply .

In the gas-dissolved water supply device (Claim 1) and the gas-dissolved water production method (Claim 8 ) of the present invention, the gas supply chamber is evacuated by the evacuation means, and the gas supply means The gas is supplied into the gas phase chamber. Thereby, it is possible to stably supply gas-dissolved water having a low dissolved gas concentration (low saturation).

If the connection port with the vacuum exhaust means is provided in the lower part of the gas phase chamber as in claim 1 , the condensed water accumulated in the gas phase chamber can be efficiently discharged.

As in claim 3 , the gas may contain oxygen. In this case, as in claim 4 , the dissolved gas concentration of the gas-dissolved water is preferably 1/400 or less of the solubility of the gas.

As in claim 5, the gas may contain carbon dioxide. In this case, as in claim 6 , the dissolved gas concentration of the gas-dissolved water is preferably 1/50 or less of the solubility of the gas.

As in claim 7 , the gas may include at least one of nitrogen, argon, ozone, hydrogen, clean air, and a rare gas.

Claims (9)

It has a gas permeable membrane module divided into a gas phase chamber and a liquid phase chamber by a gas permeable membrane, and allows water to be treated to flow into the liquid phase chamber by water passing means, and to the gas phase chamber by a gas supply means. A gas-dissolved water supply device which supplies gas and dissolves the gas from the gas phase chamber through the gas-permeable membrane into the water to be treated in the liquid phase chamber, thereby using the water to be treated as gas-dissolved water. In
A gas-dissolved water supply apparatus comprising: the vacuum exhaust means so as to supply the gas into the gas phase chamber by the gas supply means while evacuating the gas phase chamber by a vacuum exhaust means. In Claim 1, the measurement means of the dissolved gas concentration of this gas dissolved water,
A gas-dissolved water supply apparatus, comprising: a control means for controlling the dissolved gas concentration by adjusting a supply amount of the gas from the gas supply means in accordance with a measurement value of the measurement means.   3. The gas-dissolved water supply device according to claim 1, wherein a connection port with the vacuum evacuation means is provided in a lower part of the gas phase chamber.   4. The gas-dissolved water supply device according to claim 1, wherein the gas contains oxygen.   The gas-dissolved water supply device according to claim 4, wherein the dissolved gas concentration of the gas-dissolved water is 1/400 or less of the solubility of the gas.   The gas-dissolved water supply device according to any one of claims 1 to 3, wherein the gas contains carbon dioxide gas.   The gas-dissolved water supply device according to claim 6, wherein the dissolved gas concentration of the gas-dissolved water is 1/50 or less of the solubility of the gas.   4. The gas-dissolved water supply device according to claim 1, wherein the gas includes at least one of nitrogen, argon, ozone, hydrogen, clean air, and a rare gas. A method for producing gas-dissolved water using the gas-dissolved water supply device according to any one of claims 1 to 8,
Water to be treated is passed through the liquid phase chamber, and a gas is supplied into the gas phase chamber while evacuating the gas phase chamber, and the gas is supplied from the gas phase chamber through the gas permeable membrane to the liquid. A method for producing gas-dissolved water, comprising dissolving the water to be treated in a phase chamber into gas-dissolved water.

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