WO2025197613A1 - Ozone water generation device - Google Patents

Abstract

The present invention comprises: an ozone gas supply line (L1a) capable of supplying ozone gas; a circulation line (L2a) for circulating a solvent capable of dissolving ozone gas supplied via a gas-liquid mixer (21); and a control unit (6) for controlling the ozone gas supply line (L1a) and the circulation line (L2a). The ozone gas supply line (L1a) has an opening/closing valve (13) capable of switching between allowing or not allowing the ozone gas to circulate in the ozone gas supply line (L1a), and a pressure gauge (14) capable of measuring the gas pressure on the downstream side of the opening/closing valve (13) in the ozone gas supply line (L1a). The control unit (6) compares the measured value of the pressure gauge (14) with an arbitrary pressure threshold value set so as to be equal to or less than the saturated vapor pressure of the solvent, and controls the switching of the opening/closing valve (13). When the measured value of the pressure gauge (14) is the pressure threshold value or higher, the opening/closing valve (13) is closed.

Description

Ozone water generator

The present invention relates to technology that can contribute to ozone water generation devices.

Ozonated water, obtained by dissolving ozone in a solvent (such as raw water such as pure water), has strong oxidizing power and has been used, for example, in water supply systems and to sterilize food. This use of ozone water is valued as an environmentally friendly method because ozone eventually breaks down easily into oxygen and leaves no residual chemicals behind.

In recent years, efforts have been made to use ozone water in the cleaning processes used in the manufacture of various industrial parts, such as precision electronic components (e.g., semiconductor elements and display components such as FPDs), and efforts are being made to increase the concentration of this ozone water and ensure a stable industrial supply.

Patent Document 1 discloses a method for increasing the concentration of ozone water by first cooling (concentrating) ozone gas to obtain ozone water, re-evaporating the ozone gas obtained by re-evaporation (concentrated ozone gas), capturing the re-evaporated ozone gas (concentrated ozone gas) in a cooled collector, and then dissolving the captured material (liquid ozone or solid ozone) in water to obtain ozone water.

Patent Document 2 discloses that a cleaning solution obtained by simultaneously dissolving ozone gas and carbon dioxide gas in raw water (for example, raw water at 25°C or below (preferably 5°C to 20°C)) is heated to 45°C or above and then brought into contact with a resist film (organic film) on a substrate, thereby maintaining a high ozone concentration in the cleaning solution and making it easier to remove the resist film.

Patent Document 3 discloses that ozone water is produced by mixing ozone gas from an ozone gas generator (in this case, a device that uses oxygen gas as a raw material) with raw water in a gas-liquid mixer, and that by providing an orifice between the ozone gas generator and the gas-liquid mixer, it is possible to prevent the ozone gas generator side from becoming negative pressure (i.e., a state below normal pressure (approximately 101.33 kPa)), thereby increasing the efficiency of ozone gas dissolution.

Patent Document 4 discloses a system that includes an ozone water circulation line that circulates ozone water and an ozone gas contact mechanism (a permeable membrane made of fluororesin) that brings the exhaust ozone gas discharged from the ozone water circulation line into contact with raw water, thereby effectively utilizing the exhaust ozone gas to produce highly concentrated ozone water.

Patent Document 5 discloses that ozone water is generated by mixing ozone gas from an ozone gas generator (in Patent Document 5, this is a device that uses oxygen gas as a raw material) with raw material water in a gas-liquid mixer, and that ozone water that has become too low in concentration due to the raw material water (ozone water in a tank designated by the reference symbol 34 in Patent Document 5) is passed through the gas-liquid mixer to increase the concentration of the ozone water.

Non-Patent Document 1 discloses that when ozone is likely to undergo a rapid self-decomposition reaction due to an external factor (e.g., an electrical spark, a trigger due to contamination that induces decomposition, etc.), _CF4 gas is used as an inhibitor to suppress the self-decomposition reaction.

The configurations shown in Patent Documents 1 to 5 may be able to generate ozone water with a certain level of ozone concentration (for example, around 100 ppm), but cleaning processes that require relatively high oxidizing power are thought to require ozone water with an even higher concentration (for example, 200 ppm or more in the cleaning process of semiconductor elements).

Japanese Patent Application Publication No. 11-262782 Patent No. 4296393 Patent No. 4746515 Patent No. 5213601 Patent No. 7041466

Taiyo Nippon Sanso Technical Report No. 28 (2009) "Explosion Range Measurement Device"

For example, the gas-liquid mixer used in the ozone water generation apparatus shown in Patent Documents 3 and 5 has a configuration including a solvent flow passage through which a solvent (raw water, etc.) flows, and an ozone gas inlet passage connected to the solvent flow passage, which introduces ozone gas supplied to the gas-liquid mixer into the solvent flow passage.

In this type of gas-liquid mixer, suction pressure is generated in the ozone gas inlet passage depending on the flow rate (flow velocity) of the solvent flowing through the solvent flow passage. The ozone gas introduced from the ozone gas inlet passage into the solvent flow passage is mixed with and dissolved in the solvent depending on the suction pressure (hereinafter simply referred to as suction pressure) generated in the ozone gas inlet passage as described above.

However, if the suction pressure becomes too low, for example, depending on the operating conditions of the ozone water generator, the ozone gas will not dissolve easily in the solvent. This may make it difficult to produce ozone water of the desired concentration (such as high-concentration ozone water).

Furthermore, as mentioned above, if the suction pressure becomes too low, the solvent in the solvent flow passage is more likely to flow back toward the ozone gas supply source (such as the ozone gas supply line described below), which is upstream of the ozone gas introduction passage (hereinafter simply referred to as the solvent backflow phenomenon). In this case, moisture (for example, the solvent itself or water vapor evaporated from the solvent; hereinafter collectively referred to as moisture) flows into and remains on the ozone gas supply source side, making it impossible to supply ozone gas to the gas-liquid mixer as desired, which may make it more difficult to produce ozone water of the desired concentration.

The present invention was made in consideration of the above circumstances, and aims to provide technology that can contribute to making it easier to generate ozone water of the desired concentration.

The ozone water generating device of this invention can contribute to solving the above-mentioned problems, and in one aspect of the generating device, it comprises an ozone gas supply line capable of supplying ozone gas, a circulation line to which the ozone gas is supplied via a gas-liquid mixer and which circulates a solvent capable of dissolving the ozone gas, and a control unit that controls the ozone gas supply line.

The gas-liquid mixer has a solvent flow passage through which the solvent flows when the solvent is circulating, and an ozone gas inlet passage connected to the solvent flow passage, which introduces ozone gas supplied from the ozone gas supply line into the solvent flow passage.

The ozone gas supply line has a first on-off valve that can switch between allowing and disabling the flow of ozone gas through the ozone gas supply line, and a pressure gauge that can measure the gas pressure downstream of the first on-off valve in the ozone gas supply line.

The control unit compares the pressure measurement value of the pressure gauge with an arbitrary pressure threshold set to be equal to or lower than the saturated vapor pressure of the solvent, and controls the switching of the first opening/closing valve.

Furthermore, the control unit may be characterized in that the vapor pressure of the solvent, which is derived by measuring the temperature of the solvent in the circulation state, is set as the pressure threshold, and when the measurement value of the pressure gauge becomes equal to or greater than the pressure threshold, the control unit closes the first opening/closing valve.

Furthermore, the ozone gas supply line may be provided with a discharge line downstream of the first open/close valve in the ozone gas supply line, capable of discharging moisture that has flowed downstream, and the discharge line may have a second open/close valve that can switch between allowing and disallowing the flow of moisture through the discharge line.

Furthermore, the control unit may be characterized in that the vapor pressure of the solvent, which is derived by measuring the temperature of the solvent in the circulation state, is set as the pressure threshold, and when the measurement value of the pressure gauge becomes equal to or greater than the pressure threshold, the second opening/closing valve is opened.

Furthermore, a sensor capable of detecting the moisture may be provided downstream of the first on-off valve in the ozone gas supply line, and the control unit may open the second on-off valve when the moisture is detected by the sensor.

Furthermore, the control unit may be characterized by closing the first opening/closing valve when the measurement value of the pressure gauge becomes greater than the supply pressure of the ozone gas.

In another embodiment of the generation device, the device comprises an ozone gas supply line capable of supplying ozone gas, a circulation line through which the ozone gas is supplied via a gas-liquid mixer and which circulates a solvent capable of dissolving the ozone gas, and a control unit that controls the ozone gas supply line.

The gas-liquid mixer has a solvent flow passage through which the solvent flows when the solvent is circulating, and an ozone gas inlet passage connected to the solvent flow passage, which introduces ozone gas supplied from the ozone gas supply line into the solvent flow passage.

The ozone gas supply line has a first on-off valve that can switch between allowing and disabling the flow of ozone gas through the ozone gas supply line, a pressure gauge that can measure the gas pressure downstream of the first on-off valve in the ozone gas supply line, and an exhaust line that is connected to the ozone gas supply line and can exhaust gas components within the ozone gas supply line.

The exhaust line is connected to the ozone gas supply line upstream of the first on-off valve via a second on-off valve that can switch between allowing and not allowing the gas components to flow through the exhaust line.

The control unit is characterized in that when the supply of ozone gas in the ozone gas supply line is stopped and the first opening/closing valve is closed, the control unit opens the second opening/closing valve in the exhaust line.

Furthermore, the ozone gas supply line may further include a purge gas supply line capable of supplying purge gas into the ozone gas supply line, and the purge gas supply line may have a third on-off valve connected to the ozone gas supply line upstream of the first on-off valve and capable of switching between allowing and not allowing the purge gas to flow through the purge gas supply line.

Furthermore, the control unit may be characterized by opening the third on-off valve when the supply of ozone gas through the ozone gas supply line is stopped and the first on-off valve and the second on-off valve are closed.

Furthermore, an analyzer capable of detecting and analyzing the gas components may be connected to the ozone gas supply line upstream of the first on-off valve.

Furthermore, the control unit may be characterized in that, when the supply of ozone gas through the ozone gas supply line is stopped and the first on-off valve and the second on-off valve are closed, the control unit detects and analyzes the gas components using the analyzer.

As described above, the present invention can contribute to making it easier to produce ozone water of a desired concentration (such as high-concentration ozone water).

1 is a schematic diagram illustrating the configuration of an ozone water generating device A according to an embodiment. (a) is the saturated vapor pressure curve of water, and (b) is the water vapor pressure table. FIG. 2 is a schematic diagram illustrating the configuration of an ozone water generating device B according to an embodiment. FIG. 10 is a schematic diagram illustrating the configuration of a generation device B1, which is a modified example of the generation device B. FIG. 10 is a schematic diagram illustrating the configuration of a generation device B2, which is a modified example of the generation device B. FIG. 10 is a schematic diagram illustrating the configuration of a generation device B3, which is a modified example of the generation device B. FIG. 10 is a schematic diagram illustrating the configuration of a generation device B4, which is a modified example of the generation device B.

The ozone water generating device of the present invention is completely different from the configurations that simply use a gas-liquid mixer (hereinafter simply referred to as the conventional configuration) as shown in, for example, Patent Documents 3 and 5.

In other words, this embodiment includes an ozone gas supply line capable of supplying ozone gas, a circulation line for circulating a solvent capable of dissolving ozone gas supplied via a gas-liquid mixer, and a control unit for controlling the ozone gas supply line.

The ozone gas supply line has an on-off valve (in claim 1, a first on-off valve) that can switch the flow of ozone gas through the ozone gas supply line, and a pressure gauge that can measure the gas pressure downstream of the on-off valve in the ozone gas supply line.

The control unit is configured to compare the pressure measurement value of the pressure gauge with an arbitrary pressure threshold set to be below the saturated vapor pressure of the solvent, and control the switching of the on-off valve. The control unit then closes the on-off valve when the pressure measurement value of the pressure gauge exceeds the pressure threshold.

In this embodiment, when the pressure gauge measurement value exceeds the pressure threshold, the controller assumes that, for example, the suction pressure has dropped and solvent backflow may occur, and closes the on-off valve. This makes it possible to prevent moisture from flowing into the ozone gas supply line (by blocking it with the on-off valve).

If the inflow of moisture into the ozone gas supply line can be suppressed in this way, then when the suction pressure subsequently increases and the solvent backflow phenomenon is resolved (for example, when the pressure gauge measurement value falls below the pressure threshold and it can be determined that the solvent backflow phenomenon has been resolved), it becomes easier to quickly restore a state in which ozone water of the desired concentration can be produced. In other words, by opening the on-off valve using the control unit and supplying ozone gas from the ozone gas supply line to the gas-liquid mixer, the ozone gas can be introduced into the solvent flow passage via the ozone gas inlet path, enabling the ozone gas to be dissolved in the solvent.

As mentioned above, the generation device of this embodiment may be configured to switch the on-off valve in the ozone gas supply line by comparing the measurement value of the pressure gauge in the ozone gas supply line with a pressure threshold. In other words, it is possible to appropriately apply common technical knowledge in various fields (e.g., the field of ozone gas or ozone water generation, etc.) and to appropriately refer to prior art documents, etc. as needed, and to modify the design; examples described below are one example of this. Note that in the examples described below, detailed explanations will be omitted where appropriate, for example, by referring to similar content by the same reference numerals, etc.

<Reference>
For example, in a conventional configuration, if the supply pressure of ozone gas supplied to the gas-liquid mixer is simply increased (even higher than atmospheric pressure), the ozone gas becomes more soluble in the solvent, and it is possible to obtain highly concentrated ozone water. However, if the supply pressure of ozone gas is simply increased as described above, as shown in Non-Patent Document 1, a rapid self-decomposition reaction of ozone is likely to occur, making it difficult to maintain practical safety and potentially making it impossible to achieve a stable industrial supply.

Furthermore, conventional ozone gas generators (ozonizers) used in conventional configurations can generate ozone gas at low concentrations (for example, ozone concentrations of 20% by volume or less), and contain a large amount of gases made up of components other than ozone (for example, oxygen, etc.) (hereinafter referred to as non-ozone components). Even when using such low-concentration ozone gas, it is difficult to generate high-concentration ozone water, and many non-ozone components end up being dissolved.

Furthermore, ozone water, which is made highly concentrated by dissolving the above-mentioned low-concentration ozone gas in a solvent under high pressure, contains not only the ozone component but also non-ozone components dissolved in a supersaturated state. If such ozone water is released into the atmosphere, bubbles will form from the non-ozone components, which will easily disperse into the atmosphere, and at the same time, the ozone component will also easily disperse, making it impossible to maintain the high concentration of the ozone water.

In recent years, it has become possible to generate highly concentrated ozone gas (e.g., ozone concentrations of 50% by volume or more) by concentrating ozone gas generated by an ozonizer or other device using methods such as adsorption concentration (a method that utilizes surface adsorption by silica gel, etc.) or cooling concentration.

For example, Meidensha's cooling and concentration type ozone gas generator (product name: Pure Ozone Generator) is capable of generating extremely high concentrations of ozone gas (over 90% by volume), approaching approximately 100% by volume, and is certified to the international safety standard SEMI-S2, ensuring practical safety.

The supply pressure of such concentrated ozone gas is not particularly limited, and one example is to set it to a reduced pressure to prevent the sudden self-decomposition reaction mentioned above, but this is not limiting.

As an example of setting the reduced pressure state as described above, in the case of ozone gas with an ozone concentration of 90% by volume or more and an oxygen concentration of less than 10% by volume, the total pressure of the ozone gas can be reduced to 30 kPa (abs) or less (i.e., a state where the ozone partial pressure is 30 kPa (abs) or less), which allows the ozone gas to be safely maintained.

Furthermore, in the case of ozone gas with an ozone concentration of 50% by volume or more and an oxygen concentration of less than 50% by volume, the total pressure of the ozone gas can be reduced to a reduced pressure of 60 kPa (abs) or less (i.e., an ozone partial pressure of 30 kPa (abs) or less), which allows the ozone gas to be safely maintained.

When the supply pressure of ozone gas is low (for example, in the case of a reduced pressure state as described above), it is possible that solvent backflow may be more likely to occur. In such cases, it is possible to actively suppress the solvent backflow. For example, in the case of the control unit 6 described below, it is possible to appropriately acquire the status information described below and actively control (for example, control while detecting and predicting events that are likely to cause solvent backflow).

Example
<Configuration example of generation device A according to the embodiment>
1 is a schematic diagram illustrating the configuration of an ozone water generating apparatus A according to an embodiment. This apparatus A primarily comprises an ozone gas supply unit 1 capable of supplying ozone gas having an ozone concentration of 50% by volume or more (e.g., under reduced pressure), a circulation unit 2 that introduces and circulates (clockwise in FIG. 1 ) a solvent capable of dissolving the ozone gas from the ozone gas supply unit 1, a solvent supply unit 3 that supplies the solvent and gas to the circulation unit 2, and a control unit 6 that appropriately acquires information indicating the status of the ozone gas supply unit 1, circulation unit 2, solvent supply unit 3, etc. (e.g., a measurement value of a pressure gauge 14 in an ozone gas supply line L1a described below, a measurement value (circulation flow rate) of a circulation flow meter 22 in a circulation line L2a, a measurement value (solvent temperature) of a resistance temperature detector 24, etc.; hereinafter, collectively referred to as status information as needed), and controls the ozone gas supply unit 1, circulation unit 2, solvent supply unit 3, etc.

Furthermore, in the case of device A shown in Figure 1, it is equipped with a release section 4 that releases the solvent in the circulation section 2 to the outer periphery of the circulation section 2 (releasing the solvent in which ozone gas is dissolved, i.e., ozone water), and an exhaust section 5 that can exhaust the gas phase gas separated from the solvent from the circulation section 2, and each is configured so that status information is acquired and controlled as appropriate by a control section 6.

<Configuration example of ozone gas supply unit 1>
The ozone gas supply unit 1 shown in FIG. 1 mainly includes an ozone gas generator 10, an ozone gas supply line L1a that supplies ozone gas generated in the ozone gas generator 10 to the circulation unit 2 (supplying it via a gas-liquid mixer 21 described later), and a gas component discharge line L1b that is connected to the ozone gas supply line L1a and discharges gas components such as ozone gas from the ozone gas supply line L1a (for example, exhaust to adjust the gas pressure of the ozone gas supply line L1a).

The ozone gas generator 10 in this ozone gas supply unit 1 can be configured in a variety of ways, as long as it can generate ozone gas with an ozone concentration of 50% by volume or more and supply it under reduced pressure. One example is a configuration in which ozone gas generated by an ozonizer or the like is concentrated using an adsorption concentration method or a cooling concentration method.

The adsorption concentration method utilizes the surface adsorption phenomenon of silica gel, for example, to concentrate the ozone gas. If the ozone gas to be concentrated contains impurities such as NOx or heavy metals, there is a possibility that these impurities will also be concentrated during the concentration process. For this reason, if these impurities are present, it is preferable to remove them beforehand.

On the other hand, the cooling concentration method involves vaporizing the liquid ozone obtained by cooling the ozone gas to be concentrated. Furthermore, since the vapor pressures of ozone gas and impurities differ (for example, by several orders of magnitude), ozone gas concentrated using the cooling concentration method (ozone gas after vaporization) will, in principle, contain almost no impurities. Therefore, if there is a possibility that impurities may be mixed into the ozone gas to be concentrated, it is preferable to use the cooling concentration method.

Next, the ozone gas supply line L1a is equipped with a gas flow controller 11, which is configured to control the flow rate of ozone gas flowing through the ozone gas supply line L1a. Furthermore, on the upstream side of the gas flow controller 11 (the ozone gas generator 10 side), there is provided a pressure gauge 12 that measures the gas pressure of the ozone gas flowing on the upstream side (i.e., the supply pressure of the ozone gas supplied to the gas-liquid mixer 21 described below).

Furthermore, downstream of the gas flow controller 11, there is provided an on-off valve (two on-off valves in Figure 1) 13 that can be freely switched on and off to allow or block the flow of ozone gas (supply or backflow of ozone gas) in the ozone gas supply line L1a.

The on-off valve 13 (and the various on-off valves described below) may be, for example, a check valve, but is not limited to this and may be any type that can be freely switched as described above. A specific example of the on-off valve 13 is a valve that switches depending on the differential pressure between the supply pressure of ozone gas and the measurement value of the pressure gauge 14 described below (differential pressure when supply pressure > measurement value), and which closes when this differential pressure reaches a certain value (for example, 1 kPa or less).

Furthermore, a pressure gauge 14 is provided downstream of the on-off valve 13 to measure the gas pressure on that downstream side. This pressure gauge 14 can measure the gas pressure equivalent to the suction pressure when ozone gas is sucked in by the gas-liquid mixer 21 (described below), making it possible to evaluate that suction pressure.

Next, the gas component discharge line L1b is connected in communication between the gas flow controller 11 and the on-off valve 13 in the ozone gas supply line L1a and is equipped with an on-off valve 15 that can freely switch between allowing and disabling the flow (exhaust) of gas components such as ozone gas from the ozone gas supply line L1a. Also, downstream of the on-off valve 15 is an ozone decomposer (ozone killer) 16 that decomposes the gas components (particularly ozone gas) flowing through the gas component discharge line L1b into a safe state, and a vacuum pump 17 that sucks in and discharges the ozone gas after the decomposition.

<Configuration example of circulation section 2>
The circulation unit 2 shown in FIG. 1 mainly includes a circulation line L2a capable of introducing and circulating the solvent from the solvent supply unit 3, a circulation tank 20 connected to the circulation line L2a and capable of introducing and storing a certain amount of solvent, a reflux line L2b for refluxing the solvent released from the circulation tank 20 to the circulation line L2a, and a gas-liquid mixer 21 for mixing the solvent with ozone gas.

In this circulation section 2, the circulation line L2a is configured so that ozone gas supplied from the ozone gas supply section 1 to the gas-liquid mixer 21 can be introduced into the circulation line L2a via the gas-liquid mixer 21 and dissolved in the solvent. In the circulation section 2 shown in Figure 1, the circulation line L2a and the gas-liquid mixer 21 are depicted as being connected and integrated, but this is not limited to this and the two may also be separate entities.

The gas-liquid mixer 21 may be, for example, an ejector, aspirator, jet pump, etc., but is not limited to these and various configurations are possible. That is, the gas-liquid mixer 21 may be configured to have a solvent flow passage (not shown) through which the solvent flows, and an ozone gas inlet passage (not shown) connected to the solvent flow passage and for introducing ozone gas supplied to the gas-liquid mixer 21 into the solvent flow passage.

With a gas-liquid mixer 21 configured in this way with a solvent flow path and an ozone gas inlet path, suction pressure according to Bernoulli's theorem is generated in the ozone gas inlet path according to the flow rate (flow velocity) of the solvent flowing through the solvent flow path. Furthermore, vapor is generated in the ozone gas inlet path according to the saturated vapor pressure characteristics of the solvent. For example, if the solvent is raw water, the characteristics will be as shown in the saturated vapor pressure curve and water vapor pressure table of Figure 2.

According to the saturated vapor pressure characteristics of the solvent shown in Figure 2, the range of suction pressures below the saturated vapor pressure of the solvent can be derived as the range in which the ozone gas can be introduced into the solvent flow passage via the ozone gas inlet path and dissolved in the solvent (hereinafter referred to as the suction pressure range). This makes it possible to set various parameters in the control unit 6 that take the suction pressure range into consideration (for example, setting the pressure threshold described below to a value below the saturated vapor pressure).

When the control unit 6 measures (for example, using the resistance temperature detector 24 described below) the solvent temperature while it is circulating through the circulation line L2a (hereinafter simply referred to as the circulation state), the vapor pressure at that solvent temperature can be derived by comparing the measured value with the saturated vapor pressure characteristics of the solvent. Various settings can then be made taking into account the derived vapor pressure.

For example, the derived vapor pressure may be set as a pressure threshold value, as described below, or the supply pressure of ozone gas to the gas-liquid mixer 21 may be set to be greater than the derived vapor pressure.

Furthermore, based on the saturated vapor pressure characteristics of the solvent and the supply pressure of ozone gas to the gas-liquid mixer 21, it is possible to derive a solvent temperature range (hereinafter referred to as the inhalable temperature range) in which the vapor pressure in the ozone gas inlet passage of the gas-liquid mixer 21 is lower than the supply pressure. Taking into account the general solubility characteristics of gases in solvents (solubility tends to improve as the solvent temperature decreases), it is preferable to set this inhalable temperature range to a relatively low temperature range at which the solvent does not freeze (for example, a temperature higher than the freezing point of the solvent or a temperature at which the solvent can be maintained in a supercooled state).

Then, by appropriately controlling the solvent temperature using the control unit 6 so that it is within the inhalable temperature range (as in the temperature control step described below), it is possible to set the vapor pressure of the ozone gas inlet passage of the gas-liquid mixer 21 so that it is lower than the supply pressure of the ozone gas supplied to the gas-liquid mixer 21. Specifically, the measurement value of the pressure gauge 14 can be appropriately set so that it is lower than the measurement value of the pressure gauge 12. This makes it easier for the ozone gas in the ozone gas supply line L1a to be introduced into the ozone gas inlet passage of the gas-liquid mixer 21, allowing the ozone gas to be mixed and dissolved in the solvent.

Upstream of the gas-liquid mixer 21 is a circulation flowmeter 22 that measures the circulation flow rate of the solvent circulating through the circulation line L2a. Downstream of the gas-liquid mixer 21 is a circulation pump 23 (two circulation pumps in Figure 1) that circulates the solvent. By providing two circulation pumps 23a, 23b as shown in Figure 1, it is possible, for example, to operate one of the circulation pumps 23a, 23b normally and have the other function as an auxiliary pump if the primary pressure of that pump drops too much; however, the other pump may be omitted as appropriate depending on the status of the circulation section 2 (circulation conditions, etc.).

Furthermore, downstream of the circulation pump 23, there are provided resistance temperature detectors (two resistance temperature detectors in Figure 1) 24 that measure the solvent temperature, and a temperature regulator (e.g., a cooler) 25 that adjusts the solvent temperature. By appropriately controlling these resistance temperature detectors 24 and temperature regulator 25 with the control unit 6, the solvent temperature can be set to be within the suction temperature range.

Next, the circulation tank 20 has a cylindrical peripheral wall 20a with a bottom that can accommodate the introduction and storage of a fixed amount of solvent. On the upper side of the peripheral wall 20a, there is an inlet 26 that communicates with the downstream side of the resistance temperature detector 24b in the circulation line L2a (i.e., the downstream side of the gas-liquid mixer 21), an inlet 26a that communicates with the pressure adjustment line L3c (described below), and an exhaust port 26b that communicates with the gas exhaust line L5 (described below).

On the lower side of the peripheral wall 20a, there is provided an outlet 27 that communicates with the upstream side of the circulation flow meter 22 in the circulation line L2a (i.e., the upstream side of the gas-liquid mixer 21), and an outlet 28 that communicates with the solvent discharge line L4 described below.

Next, the reflux line L2b is connected so as to communicate between the upstream side of the solvent discharge line L4 (described below) and the upstream side of the circulation flow meter 22 on the circulation line L2a, and is configured so that the solvent on the upstream side of the solvent discharge line L4 (i.e., the solvent released from the discharge port 28) can be refluxed to the circulation line L2a. The reflux line L2b is also equipped with an ozone concentration meter 29 that can measure the ozone concentration of the solvent refluxed by the reflux line L2b. The ozone concentration meter 29 thus equipped on the reflux line L2b makes it possible to measure not just the ozone concentration of the solvent in the circulation line L2a, but also an ozone concentration similar to that of the solvent actually released from the circulation tank 20 (i.e., the desired ozone water).

<Configuration example of solvent supply unit 3>
The solvent supply section 3 shown in Figure 1 includes a solvent supply line L3a capable of supplying a solvent such as raw water to the circulation line L2a, a concentration adjustment line L3b capable of supplying a concentration adjustment gas (e.g., carbon dioxide gas) that stabilizes the ozone concentration of the solvent in the circulation line L2a, and a pressure adjustment line L3c capable of supplying a pressure adjustment gas (e.g., an inert gas such as _N2 , Ar, or He) that adjusts the pressure in the circulation tank 20.

In the solvent supply unit 3, the solvent supply line L3a is connected in communication between the circulation pumps 23a and 23b in the circulation line L2a and is equipped with a solvent flow rate controller 31 that can control the flow rate of the solvent flowing through the solvent supply line L3a. Also, downstream of the solvent flow rate controller 31 is equipped with a water purification unit (e.g., a water purification device) 32 that can increase the purity of the solvent flowing through the solvent supply line L3a, and an on-off valve 33 that can be freely switched on and off to allow the solvent to flow through the solvent supply line L3a.

Next, concentration adjustment line L3b is equipped with a gas flow controller 34 that is connected between circulation pumps 23a, 23b in circulation line L2a and can control the flow rate of the concentration adjustment gas flowing through concentration adjustment line L3b. Also, downstream of gas flow controller 34 is equipped with an open/close valve 35 that can switch between allowing and disallowing the flow of concentration adjustment gas through concentration adjustment line L3b.

Next, the pressure adjustment line L3c is connected in communication with the inlet 26a of the circulation tank 20 and is equipped with a gas flow controller 36 that can control the flow rate of the pressure adjustment gas flowing through the pressure adjustment line L3c.

<Configuration example of emission section 4>
1 includes a solvent discharge line L4 that discharges the solvent in the circulation tank 20 to the outer periphery of the circulation tank 20. The solvent discharge line L4 is connected in communication with the discharge port 28 in the circulation tank 20, and includes a discharge flow rate controller 41 that can control the discharge flow rate of the solvent discharged through the solvent discharge line L4.

<Configuration example of exhaust section 5>
1 includes a gas exhaust line L5 that exhausts gas (e.g., a gas phase separated from a solvent) in the circulation tank 20 to the outer periphery of the circulation tank 20. The gas exhaust line L5 is connected to the exhaust port 26b of the circulation tank 20 and includes an on-off valve (e.g., a back pressure adjustment valve) 51 that can switch between allowing and not allowing the gas in the circulation tank 20 to circulate (exhaust) while maintaining a constant pressure in the circulation tank 20. Also, downstream of the on-off valve 51, there are provided an ozone concentration measuring device 52 that can measure the ozone concentration of the ozone gas flowing through the gas exhaust line L5, and an ozone decomposer 53 that decomposes the ozone gas flowing through the gas exhaust line L5 into a safe state.

<Configuration example of control unit 6>
The control unit 6 shown in FIG. 1 may be configured to appropriately acquire and control the status information of the ozone gas supply unit 1, the circulation unit 2, the solvent supply unit 3, the release unit 4, and the exhaust unit 5 so as to obtain the desired ozone water, and various embodiments can be applied.

For example, the control unit 6 may be appropriately connected to the devices (e.g., measuring instruments, regulators, controllers, on-off valves, circulation pumps, resistance thermometers, etc.) configured on each line (ozone gas supply line L1a, gas component discharge line L1b, circulation line L2a, reflux line L2b, solvent supply line L3a, concentration adjustment line L3b, pressure adjustment line L3c, solvent release line L4, gas exhaust line L5) via signal lines (not shown).

With this type of configuration, it is possible to operate each line appropriately to obtain status information for the devices, and to output control commands to the devices based on the obtained status information.

<Example of a method for generating ozone water using device A>
In the apparatus A described above, it is possible to produce desired ozone water by appropriately performing, for example, the following circulation process, temperature control process, gas-liquid mixing process, release process, and exhaust process.

First, in the circulation step, solvent is supplied to circulation line L2a by, for example, opening the on-off valve 33 of solvent supply line L3a, filling circulation line L2a with solvent. The amount of solvent filling circulation line L2a can be set appropriately, for example, so that the liquid level of the solvent in circulation tank 20 is located between the inlet 26 and the outlet 27.

Then, by operating the circulation pump 23 of the circulation line L2a, the circulation line L2a is put into a circulating state at a predetermined circulation flow rate. During this circulating state, the concentration adjustment line L3b and pressure adjustment line L3c are also operated as necessary to stabilize the ozone concentration of the circulating solvent in the circulation line L2a and adjust the pressure inside the circulation tank 20.

Next, in the temperature control process, the inhalable temperature range is calculated in advance based on the supply pressure of the ozone gas from the subsequent ozone gas supply process and the characteristics shown in the saturated vapor pressure curve and vapor pressure table in Figure 2. Then, in the circulation state, the solvent temperature in the circulation line L2a is measured using the resistance temperature detector 24 and adjusted by the temperature regulator 25 so that the solvent temperature is within the inhalable temperature range. For example, if the target is ozone water with an ozone concentration of 300 ppm or more, the inhalable temperature range should be above the freezing point of the solvent and below 30°C, preferably below 15°C.

Next, in the gas-liquid mixing process, ozone gas is supplied to the gas-liquid mixer 21 in a circulating state by, for example, opening the on-off valve 13 on the ozone gas supply line L1a. Here, because the circulating solvent temperature is within the inhalable temperature range due to the previous temperature control process, the supply pressure of the ozone gas to the gas-liquid mixer 21 is greater than the vapor pressure of the ozone gas inlet path of the gas-liquid mixer 21.

As a result, the ozone gas supplied to the gas-liquid mixer 21 is introduced into the solvent flow passage via the ozone gas inlet passage within the gas-liquid mixer 21, where it is mixed with the solvent in the solvent flow passage and becomes soluble. Then, by dissolving the ozone gas in the solvent, the solvent reaches the desired ozone concentration.

Furthermore, when ozone gas is being supplied in the gas-liquid mixing process, if the measurement value of pressure gauge 14 becomes greater than the measurement value of pressure gauge 12, the on-off valve 13 is controlled to switch to an open state. This makes it possible to prevent the occurrence of solvent backflow into the ozone gas supply line L1a.

Next, in the release process, in the circulating state, the solvent in the circulation tank 20 is released (i.e., the desired ozone water is obtained) by appropriately controlling the release flow rate controller 41 of the solvent release line L4. Furthermore, by appropriately supplying solvent from the solvent supply line L3a to the circulation line L2a, the solvent release flow rate is controlled so that it does not exceed the solvent circulation flow rate in the circulation line L2a.

This allows the solvent to be released while maintaining a constant amount of solvent stored in the circulation tank 20. In other words, during the release process, ozone water with the desired ozone concentration can be continuously extracted.

Next, in the exhaust process, the on-off valve 51 of the gas exhaust line L5 is opened, for example, to exhaust the gas present in the circulation tank 20 (e.g., the gas phase separated from the circulating solvent) to the outer periphery of the circulation tank 20.

<Configuration example of generation device B according to the embodiment>
The device A is not limited to the configuration shown in Fig. 1 and may be modified as appropriate, for example, as shown in Fig. 3, the device B may have a configuration in which the solvent supply line L3a and the concentration adjustment line L3b of the solvent supply unit 3 are provided at positions separated from each other on the circulation line L2a. Note that in Fig. 3 (and Figs. 4 to 7 described below), parts similar to those shown in Fig. 1 are omitted as appropriate.

In the case of device B shown in Figure 3, an ozone concentration meter 29a capable of measuring the ozone concentration of the solvent circulating in the reflux line L2b is provided between the gas-liquid mixer 21 and the circulation flow meter 22 in the circulation line L2a. Furthermore, a gas-liquid mixer 38 (e.g., having a configuration similar to that of the gas-liquid mixer 21) that mixes the solvent and concentration adjustment gas is provided downstream of the pump 23 in the circulation line L2a.

The solvent supply line L3a is provided so as to communicate and connect between the gas-liquid mixer 21 and the ozone concentration measuring device 29a on the circulation line L2a. In the case of the solvent supply line L3a shown in Figure 3, a temperature regulator (e.g., a heat exchanger) 37 that adjusts the solvent temperature on the upstream side of the solvent flow rate controller 31 on the solvent supply line L3a is provided. This may make it easier to set the solvent temperature of the solvent circulating through the gas-liquid mixer 21 as desired, compared to the case of device A in Figure 1.

The concentration adjustment line L3b is connected to the circulation line L2a downstream of the pump 23 via a gas-liquid mixer 38. This may make it easier to supply concentration adjustment gas to the solvent in the circulation line L2a compared to the case of device A in Figure 1.

In the above-described device B, as with device A, the desired ozone water can be produced by appropriately performing the circulation process, temperature control process, gas-liquid mixing process, release process, and exhaust process described above.

<Configuration example for easily suppressing or eliminating solvent backflow phenomenon>
In the apparatuses A and B, even if the suction pressure drops depending on the operating conditions of the apparatuses A and B (e.g., solvent temperature, circulation state), and a state is reached where solvent backflow may occur in the ozone gas supply line L1a, the solvent backflow can be suppressed or eliminated by previously setting the inhalable pressure range and inhalable temperature range as described above in the control unit 6 and appropriately controlling the switching of the on-off valve 13.

An example of a configuration for suppressing or eliminating the solvent backflow phenomenon will be described below based on devices B1 and B2 shown in Figures 4 and 5, which are modifications of device B. Note that in the control unit 6 of devices B1 and B2, the pressure threshold for comparison with the measurement value of the pressure gauge 14 is set within the inhalable pressure range.

In the device B1 shown in Figure 4, for example, when ozone gas is being supplied through the gas-liquid mixing process, the control unit 6 reads the measurement value of the pressure gauge 14 at predetermined time intervals and compares the measurement value with the pressure threshold value to make a judgment. At this time, if the suction pressure of the gas-liquid mixer 21 is decreasing due to, for example, the operating status of the device B1, the measurement value of the pressure gauge 14 will increase.

If the control unit 6 determines that the measurement value of the pressure gauge 14 is equal to or greater than the pressure threshold, it closes the on-off valve 13 and temporarily suspends or stops the gas-liquid mixing process.

As a result, even if the suction pressure drops, causing a solvent backflow phenomenon and allowing moisture to flow into the ozone gas supply line L1a, the on-off valve 13 can suppress or block the moisture.

Then, the control unit 6 reads the measurement value of the pressure gauge 14 and compares it with the pressure threshold. If it determines that the measurement value of the pressure gauge 14 is less than the pressure threshold (i.e., if it is determined that the solvent backflow phenomenon has been resolved), the on-off valve 13 is opened, and the gas-liquid mixing process can be resumed.

In the device B2 shown in Figure 5, a sensor 13c (e.g., a water level sensor, infrared sensor, electromagnetic wave sensor, etc.) capable of detecting moisture that has flowed downstream of the on-off valve 13 is provided on the ozone gas supply line L1a downstream of the on-off valve 13 (between the on-off valve 13 and the gas-liquid mixer 21). In addition, a moisture discharge line L1c capable of discharging moisture that has flowed downstream of the on-off valve 13 is connected in communication with the downstream side of the on-off valve 13. This moisture discharge line L1c is equipped with an on-off valve 13d that can switch between allowing and disallowing moisture to flow from the downstream side of the on-off valve 13. This on-off valve 13d is typically kept closed, for example, during the gas-liquid mixing process.

The control unit 6 of such device B2, for example, monitors the condition downstream of the on-off valve 13 (presence or absence of moisture, etc.) using sensor 13c, while reading the measurement value of the pressure gauge 14 at predetermined time intervals, just as with device B1, and compares the measurement value with a pressure threshold to make a judgment.

Then, when the control unit 6 detects moisture downstream of the on-off valve 13 via the sensor 13c, or/and determines that the measurement value of the pressure gauge 14 is above the pressure threshold, it closes the on-off valve 13 and temporarily suspends or stops the gas-liquid mixing process.

As a result, even if the suction pressure drops, causing a solvent backflow phenomenon and allowing moisture to flow into the ozone gas supply line L1a, the on-off valve 13 can suppress or block the moisture. At this time, the on-off valve 13d may be opened. This makes it possible to discharge the moisture via the moisture discharge line L1c, even if moisture is flowing downstream of the on-off valve 13, for example.

Then, the control unit 6 reads the measurement value of the pressure gauge 14 and compares it with the pressure threshold. If it determines that the measurement value of the pressure gauge 14 is less than the pressure threshold, or/and if no moisture is detected by the sensor 13c, the on-off valve 13 is opened (and the on-off valve 13d is closed), and the gas-liquid mixing process can be resumed.

If it is acceptable for a certain amount of moisture to flow into the ozone gas supply line L1a of the devices B1 and B2 described above due to solvent backflow, then, for example, as shown in Figures 4 and 5, the gas-liquid mixer 21 and the on-off valve 13 in the ozone gas supply line L1a can be positioned away from each other (separated by a predetermined distance), with an allowable space 13e provided between them.

For example, if the top-to-bottom direction of devices B1 and B2 is the same as the vertical direction shown in Figures 4 and 5 (hereinafter simply referred to as the top-to-bottom direction), moisture that flows into allowable space 13e will be stored in order from the bottom side of allowable space 13e (the gas-liquid mixer 21 side).

As a result, even if the suction pressure drops, causing a solvent backflow phenomenon and allowing moisture to flow into the ozone gas supply line L1a, it is possible to suppress the inflow of moisture upstream of the on-off valve 13 without switching the on-off valve 13 or the like (i.e., even if the on-off valve 13 is open) until the allowable space 13e is filled with moisture.

Furthermore, the capacity of the allowable space 13e can be set as appropriate, and the larger the capacity, the easier it may be to suppress the inflow of moisture upstream of the on-off valve 13.

<Example of a configuration for removing moisture remaining in the ozone gas supply line L1a>
In the case of conventional configurations, if moisture is present in a portion of the ozone gas supply source that is easily oxidized (for example, piping, joints (welds), various devices, etc., made of metallic or organic materials), and the portion is exposed to ozone gas, the moisture and ozone gas interact with each other, facilitating corrosion of the portion. Furthermore, the ozone gas is easily decomposed in the corroded portion, which may make it even more difficult to produce ozone water of the desired concentration.

On the other hand, in devices A and B, even if moisture (water vapor, etc.) flows into the ozone gas supply line L1a due to, for example, a solvent backflow phenomenon and remains (for example, moisture adhering to the inner surface of the ozone gas supply line L1a), the moisture can be discharged via the gas component discharge line L1b by appropriately controlling the ozone gas supply line L1a and the gas component discharge line L1b using the control unit 6 (for example, appropriately switching and controlling the on-off valves 13, 15, etc.).

An example of a configuration for discharging moisture in this manner is described below based on device B3 shown in Figure 6, which is a modified version of device B. Note that when the on-off valve 18a (described below) is closed, the supply of ozone gas from the ozone gas generator 10 is stopped.

The device B3 shown in Figure 6 is equipped with an open/close valve 18a on the upstream side (ozone gas generator 10 side) of the gas flow controller 11 on the ozone gas supply line L1a, which can be freely switched between allowing and not allowing the flow of ozone gas (or gas components containing residual moisture and the purge gas described below) on this upstream side.

Furthermore, a purge gas supply line L1d capable of supplying purge gas is connected between the on-off valves 13, 18a on the ozone gas supply line L1a (hereinafter simply referred to as between the on-off valves 13, 18a) and communicates with the two (connected between the gas flow controller 11 and the on-off valve 18a in FIG. 6). This purge gas supply line L1d is equipped with an on-off valve 18b that can freely switch between allowing and not allowing the flow of the purge gas (or gas components containing moisture, etc. remaining in the ozone gas supply line).

In the case of the purge gas supply line L1d shown in Figure 6, an analyzer 18c capable of detecting and analyzing gas components remaining upstream of the on-off valve 18a in the ozone gas supply line is provided upstream of the on-off valve 18b in the purge gas supply line L1d.

The control unit 6 of such device B3 may, for example, appropriately perform the gas component discharge process, purging process, and analysis process described below.

First, in the gas component discharge process, the control unit 6 closes the on-off valves 13, 18a, and 18b and opens the on-off valve 15, and operates the pump 17, thereby sucking and discharging the gas components remaining between the on-off valves 13 and 18a via the gas component discharge line L1b.

This gas component discharge process may be carried out (for example, for about one hour) until the pressure between the on-off valves 13 and 18a (measurement value of the pressure gauge 12) does not increase when the on-off valve 15 is closed after the gas components are sucked and discharged via the gas component discharge line L1b as described above.

During the purging process, the control unit 6 closes the on-off valves 13 and 18a and opens the on-off valves 15 and 18b, and operates the pump 17 appropriately. This allows the purge gas from the purge gas supply line L1d to be supplied between the on-off valves 13 and 18a, while the gas components remaining between the on-off valves 13 and 18a are sucked in and discharged (together with the purge gas) via the gas component discharge line L1b.

In such a purging process, various inert gases (e.g., inert gases such as _N2 , Ar, He, etc.) or dry oxygen (e.g., with a dew point of -60°C or higher) can be used as the purge gas, and the purge process is not particularly limited, and can be carried out appropriately (for example, for about one hour).

In the analysis process, for example, after the gas component discharge process and purging process described above have been performed, the control unit 6 closes the on-off valves 13, 15, and 18a and opens the on-off valve 18b, and operates the analyzer 18c as appropriate, thereby analyzing the gas components remaining between the on-off valves 13 and 18a.

If this analysis process confirms that the gas component contains moisture, the gas component discharge process and purging process described above can be repeated as appropriate.

Analyzer 18c may be any device capable of analyzing the gas components remaining between valves 13 and 18a, as described above. Examples include a dew point meter, an infrared spectrophotometer (IR), a mass spectrometer (MS), etc.

When using a dew point meter, the gas components between the on-off valves 13 and 18a can be introduced into the dew point meter (for example, with the on-off valve 18a slightly open) to check whether the dew point increases.

When an infrared spectrophotometer is used, the gas components between the on-off valves 13 and 18a are introduced into the infrared spectrophotometer (gas cell for infrared spectroscopy), and the presence or absence of an increase in the peak at a wave number of 3000 to 4000 cm ^−1, which indicates the presence of water, can be confirmed.

When using a mass spectrometer, the gas components between the on-off valves 13 and 18a can be introduced into the mass spectrometer, and the presence or absence of an increase in the peak intensity at m/z = 18, which indicates the presence of water, can be confirmed.

<Example of a configuration for suppressing temperature rise of the circulating solvent>
In the apparatuses A and B, the solvent temperature may be prone to rise depending on, for example, the operating conditions and installation environment of the apparatuses A and B. For example, if the ambient temperature on the outer periphery of the circulation line L2a is high (e.g., higher than the desired solvent temperature) or if heat-generating equipment (e.g., the circulation pump 23) is present in the circulation line L2a, the heat from the ambient temperature or the heat-generating equipment may be transferred into the circulation line L2a, making it impossible to maintain the desired solvent temperature and resulting in a temperature rise. If the solvent temperature cannot be maintained and rises (e.g., higher than the temperature at the time of dissolution in the gas-liquid mixer 21), the ozone gas dissolved in the solvent may be degassed over time, resulting in a decrease in the ozone concentration.

In such cases, it may be possible to cover at least a portion of the outer periphery of the circulation line L2a with heat insulating material or to cool it appropriately using a cooling means. For example, in the case of device B4 shown in Figure 7, which is a modified version of device B, at least a portion of the outer periphery of the circulation line L2a, region R (the area surrounded by a dashed line in Figure 7), may be covered with heat insulating material or a cooling jacket not shown. In the case of region R shown in Figure 7, this region excludes the circulation flow meter 22, circulation pump 23, and ozone concentration measuring instrument 29a.

If such region R is covered with insulating material, the heat from the ambient temperature of the circulation line L2a and the heat from heat-generating equipment can be prevented from being transferred into the circulation line L2a, making it easier to maintain the desired solvent temperature.

When region R is covered with a cooling jacket, it is possible to prevent the heat from the ambient temperature of circulation line L2a and the heat from heat-generating equipment from being transferred into circulation line L2a, and it is also possible to cool circulation line L2a, making it easier to maintain the desired solvent temperature.

The cooling jacket can be applied in various forms and is not particularly limited. For example, when a double-pipe structure is applied, the inner pipe of the double-pipe structure can be used as the circulation line L2a, and the refrigerant can be circulated appropriately through the outer pipe of the double-pipe structure.

When the cooling jacket cools the solvent circulating in the circulation line L2a, it is preferable to appropriately control the refrigerant temperature of the cooling jacket using the control unit 6 so that it is at least lower than the ambient temperature of the circulation line L2a.

More preferably, the circulating solvent is cooled to as low a temperature as possible without freezing. For example, an antifreeze (such as ethylene glycol) can be used as the refrigerant, and the temperature of the refrigerant can be appropriately controlled so that it is higher than the temperature at which the circulating solvent freezes, but below zero degrees Celsius.

By cooling the solvent in this way, it is possible to maintain a supercooled state in the solvent, meaning that even if the solvent is cooled to or below its freezing point, the solvent will not begin to freeze and will remain in a non-frozen state.

In addition to using heat insulating materials or a cooling jacket as described above, another option is to fill a container capable of housing the circulation line L2a with a refrigerant and immerse the circulation line L2a in the refrigerant to cool it.

The present invention has been described in detail above only with reference to the specific examples. However, it will be clear to those skilled in the art that numerous modifications are possible within the scope of the technical concept of the present invention, and it is natural that such modifications fall within the scope of the claims.

For example, devices A, B, B1 to B4 may be applied separately, or their respective components may be combined appropriately. Furthermore, the technical concepts beyond the claims that can be understood from the above-described embodiments are described below.

[1-1]
an ozone gas supply line capable of supplying ozone gas;
a circulation line to which the ozone gas is supplied via a gas-liquid mixer and which circulates a solvent capable of dissolving the ozone gas;
Equipped with
The gas-liquid mixer is
a solvent flow path through which the solvent flows in a circulating state;
an ozone gas inlet line connected to the solvent flow passage and configured to introduce the ozone gas supplied from the ozone gas supply line into the solvent flow passage;
and
The ozone water generating apparatus is characterized in that at least a portion of the outer periphery of the circulation line is covered with a heat insulating material.

[1-2]
an ozone gas supply line capable of supplying ozone gas;
a circulation line to which the ozone gas is supplied via a gas-liquid mixer and which circulates a solvent capable of dissolving the ozone gas;
Equipped with
The gas-liquid mixer is
a solvent flow path through which the solvent flows in a circulating state;
an ozone gas inlet line connected to the solvent flow passage and configured to introduce the ozone gas supplied from the ozone gas supply line into the solvent flow passage;
and
The ozone water generating apparatus is characterized in that at least a portion of the outer periphery of the circulation line is covered with a cooling jacket through which a refrigerant can circulate.

[1-3]
a control unit capable of controlling the temperature of the refrigerant circulated through the cooling jacket,
The ozone water generating device of [1-2] is characterized in that the control unit controls the temperature of the refrigerant so that it is higher than the temperature at which the solvent freezes in the circulating state and is below zero degrees Celsius.

[1-4]
The ozone water generating device of [1-2] is characterized in that the control unit controls the temperature of the solvent in the circulation state so that it is higher than the temperature at which the solvent in the circulation state becomes frozen and lower than the temperature of the outer periphery of the cooling jacket.

A, B, B1 to B4...Generation device 1...Ozone gas supply section 2...Circulation section 3...Solvent supply section 4...Discharge section 5...Exhaust section 6...Control section L1a...Ozone gas supply line L2a...Circulation line 21...Gas-liquid mixer

Claims (11)

an ozone gas supply line capable of supplying ozone gas;
a circulation line to which the ozone gas is supplied via a gas-liquid mixer and which circulates a solvent capable of dissolving the ozone gas;
a control unit that controls the ozone gas supply line;
Equipped with
The gas-liquid mixer is
a solvent flow path through which the solvent flows in a circulating state;
an ozone gas inlet line connected to the solvent flow passage and configured to introduce the ozone gas supplied from the ozone gas supply line into the solvent flow passage;
and
The ozone gas supply line
a first opening/closing valve capable of switching between allowing and not allowing the ozone gas to flow through the ozone gas supply line;
a pressure gauge capable of measuring a gas pressure downstream of the first on-off valve in the ozone gas supply line;
and
The control unit compares the measured value of the pressure gauge with an arbitrary pressure threshold set to be lower than the saturated vapor pressure of the solvent, and controls the switching of the first opening/closing valve. The control unit
a vapor pressure of the solvent derived by measuring a temperature of the solvent in the circulating state is set as the pressure threshold value;
2. The ozone water generating apparatus according to claim 1, wherein the first opening/closing valve is closed when the measured value of the pressure gauge becomes equal to or greater than the pressure threshold value. the ozone gas supply line is provided with a discharge line downstream of the first open/close valve in the ozone gas supply line, the discharge line being capable of discharging moisture that has flowed into the downstream side,
2. The ozone water generating apparatus according to claim 1, wherein the discharge line has a second opening/closing valve that can switch between allowing and not allowing the water to flow through the discharge line. The control unit
a vapor pressure of the solvent derived by measuring a temperature of the solvent in the circulating state is set as the pressure threshold value;
4. The ozone water generating apparatus according to claim 3, wherein the second opening/closing valve is opened when the measured value of the pressure gauge is equal to or greater than the pressure threshold value. a sensor capable of detecting the moisture is provided downstream of the first open/close valve in the ozone gas supply line,
4. The ozone water generating apparatus according to claim 3, wherein the control unit opens the second opening/closing valve when the sensor detects the moisture. The ozone water generating device of claim 1, characterized in that the control unit closes the first opening/closing valve when the measured value of the pressure gauge becomes greater than the supply pressure of the ozone gas. an ozone gas supply line capable of supplying ozone gas;
a circulation line to which the ozone gas is supplied via a gas-liquid mixer and which circulates a solvent capable of dissolving the ozone gas;
a control unit that controls the ozone gas supply line;
Equipped with
The gas-liquid mixer is
a solvent flow path through which the solvent flows in a circulating state;
an ozone gas inlet line connected to the solvent flow passage and configured to introduce the ozone gas supplied from the ozone gas supply line into the solvent flow passage;
and
The ozone gas supply line
a first opening/closing valve capable of switching between allowing and not allowing the ozone gas to flow through the ozone gas supply line;
a pressure gauge capable of measuring a gas pressure downstream of the first on-off valve in the ozone gas supply line;
an exhaust line connected to the ozone gas supply line and capable of exhausting gas components in the ozone gas supply line;
and
the exhaust line is connected to the ozone gas supply line on the upstream side of the first open/close valve via a second open/close valve that can switch between allowing and not allowing the gas component to flow through the exhaust line,
The ozone water generating apparatus is characterized in that the control unit opens the second opening/closing valve in the exhaust line when the supply of ozone gas in the ozone gas supply line is stopped and the first opening/closing valve is closed. the ozone gas supply line further includes a purge gas supply line capable of supplying a purge gas into the ozone gas supply line,
The purge gas supply line is
the ozone gas supply line is connected to the upstream side of the first opening/closing valve,
8. The ozone water generating apparatus according to claim 7, further comprising a third opening/closing valve that can switch between allowing and not allowing the purge gas to flow through the purge gas supply line. The ozone water generating device of claim 8, characterized in that the control unit opens the third on-off valve when the supply of ozone gas in the ozone gas supply line is stopped and the first on-off valve and the second on-off valve are closed. The ozone water generating device of claim 7, characterized in that an analyzer capable of detecting and analyzing the gas components is connected to the ozone gas supply line upstream of the first on-off valve. The ozone water generating device of claim 10, characterized in that the control unit detects and analyzes the gas components using the analyzer when the supply of ozone gas in the ozone gas supply line is stopped and the first on-off valve and the second on-off valve are closed.