TWI690483B - Ozone gas generation system and ozone gas generation method - Google Patents

Abstract

An object of the present invention is to provide an ozone gas generation system capable of outputting high concentration ozone to the outside with the system configuration minimized. The ozone gas generation system (1000) according to the present invention includes an ozone generator (200) having a plurality of discharge cells stacked in multiple stages, and the ozone generator (200) satisfies the condition (1) of “the discharge area so of the discharge surface of each of the plurality of discharge cells is in the range of about 30 cm² to 160 cm²", the condition (2) of “the source gas flow rate qo of the source gas supplied to the discharge space of each of the plurality of discharge cells is in the range of 0.5 L/min to 2.5 L/min”, and the condition (3) of “the discharge power density J in the discharge space of each of the plurality of discharge cells is in the range of 2.5 W/cm² to 6 W/cm²”.

Description

Ozone gas generating system and ozone gas generating method

The present invention relates to an ozone gas generating system that outputs high-concentration ozone gas through the configuration of an ozone power supply and an ozone generator that utilizes a discharge phenomenon. In particular, the discharge gap length d is set to a short gap in the range of tens of μm to hundreds of μm, and the combination of the ozone generator and the power supply for ozone can be used to output high-concentration ozone gas or high-generation ozone gas Ozone gas generation system.

In general, a discharge-type ozone gas generating device is composed of a combination of an ozone power supply for supplying an ozone gas generating power supply and an ozone generator having a built-in ozone gas generating discharge chamber (ozone generating chamber).

The discharge chamber has a discharge space separated by a dielectric substance. By applying a high-voltage type ozone generating AC voltage to the ozone generator from a power supply for ozone, a dielectric barrier discharge (silent discharge) can be excited in the discharge space of the discharge chamber ). The discharge space where the dielectric barrier discharge is generated includes: a discharge generating device using oxygen gas added with a catalyst gas for ozone gas generation as a raw material gas, or supplying high-purity oxygen gas without added catalyst gas as a raw material gas, and Two types of devices, such as a discharge generator for applying a photocatalyst material for ozone gas generation on the discharge surface of the dielectric barrier Set. By separately applying discharge energy to the raw material gases supplied to the two types of discharge generating devices, high-concentration ozone gas can be generated by the catalyst.

The ozone gas generated in the discharge chamber is collected, and the ozone gas with a predetermined ozone concentration is taken out from the ozone generator to form an ozone gas generating device. Examples of the ozone generator used in the ozone gas generating apparatus are disclosed in Patent Document 1.

The ozone generators disclosed in various prior art documents are of course aimed at ozone generators which add catalyst gas for generating ozone gas or apply photocatalyst material on the discharge surface. Among the elements of the invention described later, the explicit statement about the ozone generator in which the catalyst gas is added to the source gas or the photocatalyst material is applied to the discharge surface is omitted, but of course it is an ozone generator that applies the above measures Explain as a premise.

Furthermore, the total ozone generation amount Y (g/h) generated by the ozone generator per unit time is the total gas flow rate Q (L/min) of the raw material gas supplied to the discharge space of the discharge chamber and the ozone input The amount corresponding to the total discharge power DW(W) of the generator, which satisfies the condition of the following formula (1).

Y=Q‧C...(1)

In addition, "C" in the formula (1) is the ozone generation concentration (g/m ³ ) generated in the discharge cell.

That is, the total ozone generation amount Y(g/h) generated by the ozone generator is the product of the generated ozone generation concentration C(g/m ³ ) and the total gas flow rate Q(L/min) of the supplied raw material gas The corresponding value.

Incidentally, the ozone generation concentration C (g/m ³ ) generated in the discharge chamber corresponds to the discharge power DW (watt=joule‧sec.) injected into the unit gas volume V (cm ³ ) per unit time. In addition, in the entire ozone gas generator, only the unit gas volume V (cm ³ ) satisfies the following formula (2).

V(cm ³ /sec)=1000‧Q/60...(2)

That is, the ozone generation concentration C (g/m ³ ) generated in the discharge chamber is determined by the specific power value DW corresponding to the discharge energy (joule/cm ³ ) per unit gas volume V (cm ³ ) injected into the ozone generation chamber /Q(W‧min/L) to decide.

Therefore, the ozone generation concentration C (g/m ³ ) will increase the generation concentration in proportion to the specific power value DW/Q (W‧min/L). The ozone generation concentration C (g/m ³ ) is expressed by the following formula (3).

C(g/m ³ )=A‧DW/Q...(3)

In addition, in the formula (3), "A(g/J)" is an inherent proportional constant representing the ozone generating capacity per unit discharge energy provided by the discharge chamber. The "A(g/J)" which belongs to the intrinsic value means the ability value that can generate ozone by various catalyst chemical reactions caused by electron collision or discharge. If described in more detail, "A(g/J)" can be said to depend on the inherent value of the discharge form, gas type, discharge surface material, and discharge gap length d.

Incidentally, with respect to the total amount of ozone generated per unit time Y (g/h), the amount of ozone remaining in the discharge space in the discharge chamber that generates the ozone generation concentration C derived from equation (3) Ys (g ) Is represented by the following formula (4).

Ys(g)=C‧d‧S/1000000...(4)

"D" in equation (4) is the discharge gap length (cm), and "S" is the total discharge area (cm ² ) of the ozone generator. The amount of ozone Ys remaining in the discharge space of the discharge chamber is not only the value A of generating ozone or the specific power value DW/Q value, but also determined by the length d of the discharge gap and the total discharge area S belonging to the structural factor of the discharge chamber The fixed value of the parameter value cannot be changed if the structure of the discharge chamber is determined.

FIG. 7 is a graph showing the characteristic of the extracted ozone concentration Ct with respect to the specific power value DW/Q in the conventional ozone generating device.

In addition, the extracted ozone amount Yt of the ozone generating device and the product of the extracted ozone concentration Ct and the supplied gas flow rate Q roughly correspond to values. This means that the maximum gas supply is possible The raw material gas of flow rate Q can be obtained from the ozone concentration Ct value and specific power value DW/Q value shown in Figure 7 to obtain the maximum value of the ozone extraction amount Yt (=Ct‧Q) of the ozone generator. The maximum value of the injected discharge power DW (=specific power value (DW/Q)‧Q) can be obtained.

In the ozone gas generating device, the ozone generating concentration C and the ozone amount Ys calculated according to equations (3) and (4) are generated. On the other hand, as shown in FIG. 7, in the ozone gas generating device using the discharge phenomenon, the characteristic of the specific power value DW/Q of the ozone concentration Ct with respect to the ozone generator is characteristic 8000a. In the characteristic 8000a, a tangent (two-dot chain line) showing the characteristic of taking out the ozone concentration Ct with respect to the low specific power value DW/Q means the ozone generation concentration C corresponding to the ozone amount Ys remaining in each discharge cell.

On the other hand, the extracted ozone concentration Ct of the high specific power value DW/Q is a value obtained by subtracting the decomposition concentration Cd of ozone generated in each discharge chamber from the ozone generation concentration C (two-dot chain line) generated in each discharge chamber. That is, the extracted ozone concentration Ct represents the actual ozone concentration extracted from the ozone gas generating device.

Here, the ozone generator using high-purity oxygen as a raw material gas is considered. In this type of ozone generator, the main reason for determining the ozone generating capacity expressed by the ozone generating characteristic (two-dot chain line) with respect to the specific power value DW/Q (W‧min/L) is considered to be Patent Document 2 Dielectric barrier discharge (silent discharge) generated in the discharge space of the discharge cell shown in Patent Document 6. As shown in each patent document, the amount of dissociation of oxygen atoms due to electron collision in the discharge space is very small, and the ozone generation ability due to electron collision is only a very small part of the generation of high-concentration ozone.

That is, when the total discharge power DW is supplied to the ozone generator and a dielectric barrier discharge occurs in the discharge space of the discharge chamber, by the "catalyst effect of trace nitrogen contained in the supplied raw material gas", or " The photocatalyst function arranged on the entire surface of the electrode constituting the discharge chamber" can increase the dissociation amount of oxygen atoms to generate high-concentration ozone gas.

According to this phenomenon, the dissociation ability of oxygen atoms due to a small amount of nitrogen or the dissociation ability of oxygen atoms of the photocatalyst arranged on the electrode surface is the main cause of ozone gas.

Regarding the ozone generation concentration C (g/m ³ ) generated in the discharge chamber, the higher the above oxygen atom dissociation ability, the higher the A (g/J) value shown in formula (3), and the discharge space can be produced The greater the amount of ozone gas.

In addition, in the discharge chamber, by injecting discharge energy (J), although an ozone gas whose ozone concentration follows equation (3) with A(g/J) as a parameter is generated, the generated ozone gas will At the same time, self-decomposition and decomposition caused by collision with the discharge gas occur in the discharge chamber. The sum of the ozone gas self-decomposition in the discharge chamber and the ozone decomposition amount caused by the collision with the discharge gas is larger than the usual ozone gas self-decomposition amount in the extraction atmosphere.

This situation means that, in the discharge space, the dissociation of oxygen atoms due to electron collision accounts for a large proportion compared with the ozone generating ability. That is, this shows the amount of ozone gas decomposition that returns to oxygen due to the dissociation of the generated ozone due to the collision of electrons, ions, and discharge gas in the discharge plasma, and the ozone decomposition of ozone in the high concentration ozone state in the discharge chamber. The amount of ozone decomposition is greater than the amount of ozone in the atmosphere, so the amount of ozone decomposition in the discharge plasma cannot be ignored.

Therefore, the decomposition concentration Cd of the ozone gas generated in each discharge chamber can also be considered as an element that depends on the total discharge power DW or the total gas flow rate Q that is input.

In the conventional ozone gas generating device shown in FIG. 7, if the practical environment of the device is considered, it can be inferred that the total gas flow rate Q of the raw material gas must be in the gas flow rate region of about 2.4 L/min or more, and cooling ozone generation The cooling temperature of the device is ideally set at the restriction condition above 5°C. In addition, it is also conceivable that the upper limit of the cooling temperature limit condition for cooling the ozone generator is set at about 30°C relative to the normal temperature (20°C) to operate the ozone gas generating device.

Under the above restriction conditions, even if it is set at a high specific power value DW/Q (near 500W‧min/L) to increase the extracted ozone concentration Ct, the conventional ozone gas generating device cannot obtain high-concentration ozone gas exceeding 400g/m ³ .

Prior technical literature Patent Literature

[Patent Document 1] Japanese Patent No. 3607890

[Patent Document 2] Japanese Patent No. 3642572

[Patent Document 3] Japanese Patent No. 4953814

[Patent Document 4] Japanese Patent No. 5069800

[Patent Document 5] Japanese Patent No. 4825314

[Patent Document 6] Japanese Patent No. 4932037

The conventional ozone gas generating device is composed of an existing power source for ozone and an existing ozone generator in the shape of a discharge chamber.

In the conventional ozone gas generating device, if the total gas flow rate Q of the raw material gas is in a large large gas flow rate region, the total discharge power DW is increased, and the high specific power value DW/Q (500W‧min/L Nearby), in each discharge chamber, the amount of ozone gas decomposed in the ozone gas generating device is very large with respect to the generated ozone generating concentration C, so that the extracted ozone concentration Ct cannot be increased to a predetermined concentration or more.

Therefore, in the conventional ozone gas generating device, there is a limit to the ozone concentration Ct that can be taken out. The ozone concentration that can be taken out from the ozone gas generating device is in a large gas flow area, and there is a problem that it is impossible to take out a higher concentration of ozone gas.

In particular, in the conventional ozone gas generating device having the characteristics shown in FIG. 7, in the ozone concentration characteristic of the specific power value DW/Q with respect to the large gas flow rate region, it is impossible to take out a high concentration exceeding 400 g/m ³ ( Concentration in area 99a) ozone gas.

In addition, in the discharge chamber, even if the power input for the discharge is increased and the amount of ozone generated is increased, the decomposition amount of the ozone gas becomes larger, and there is a problem that the concentration of the extracted ozone cannot be increased. Furthermore, there is also a problem in that the voltage applied to the load increases when the discharge input power is increased in order to increase the ozone extraction amount Yt and the discharge power density is increased. Moreover, when the AC output is set at a higher frequency, there is a problem that the power supply for ozone cannot be stably supplied with an AC voltage for ozone generation, and the discharge power density in power supply control is limited.

In order to solve the above-mentioned problems, an object of the present invention is to provide an ozone gas generation system that can suppress the system configuration to the minimum necessary level and can output high-concentration ozone to the outside.

The ozone gas generating system of the present invention includes: an ozone generator having a discharge chamber disposed on a pair of flat electrodes via a dielectric; and a power supply for ozone, which applies an ozone generating AC voltage to the ozone generator to generate the ozone The device supplies oxygen-containing raw material gas, the ozone generator generates a dielectric barrier discharge in the discharge space of the discharge chamber, generates ozone gas from the raw material gas supplied to the discharge space, and outputs the ozone gas to the outside, The discharge chamber includes multiple discharge chambers stacked in multiple stages. The ozone generator is characterized by satisfying the following conditions (1) and (2). The conditions (1) and (2) are as follows. Condition (1): discharge area of each discharge surface line so the plurality of discharge cells is set in 30cm ² or more less than 160cm ² range; Condition (2): the raw material supplied to the discharge by each of the plurality of discharge chambers chambers The raw material gas flow rate qo of the gas is set in the range of 0.5 L/min or more and not up to 2.5 L/min.

The ozone gas generation system of the present invention shortens the gas residence time To in the discharge space of each discharge chamber by satisfying the condition (1) and the condition (2), and can reduce the collision of ozone gas with electrons, ions, and discharge gas. The amount of ozone gas generated or the self-ozonolysis of ozone generated in the discharge chamber is suppressed.

As a result, the ozone gas generating system of the present invention can achieve the effect of being able to take out a higher concentration of ozone gas from the ozone generator.

The purpose, features, aspects, and advantages of the present invention will be made clearer by the following detailed description and accompanying drawings.

1‧‧‧Earth cooling electrode

2a, 2b ‧‧‧ dielectric electrode

3a, 3b‧‧‧High voltage electrode

4a, 4b‧‧‧Insulation board

5‧‧‧ Low-pressure cooling plate

6‧‧‧Layer compression spring

7‧‧‧Layer pressing plate

8‧‧‧Layer pressure bar

9‧‧‧ Manifold box block

10‧‧‧Abutment

11‧‧‧ Generator cover

13‧‧‧ spacer

15‧‧‧Opening

17‧‧‧Output path

21AC-DC‧‧‧Converter Circuit Department

22‧‧‧Inverter circuit

23‧‧‧Restriction Reactor

24‧‧‧Power control circuit

25‧‧‧Parallel resonance transformer

91‧‧‧ Cooling water output path

92‧‧‧Ozone gas output path

93‧‧‧ Cooling water input path

100‧‧‧Ozone power supply

200‧‧‧Ozone generator

1000‧‧‧Ozone gas generating system

HV‧‧‧High voltage terminal

LV‧‧‧Low voltage terminal

DW(W)‧‧‧Total discharge power

G _IN ‧‧‧ Raw gas

G _OUT ‧‧‧ output ozone gas

FIG. 1 is an explanatory diagram of the configuration of an ozone gas generating system according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of the discharge surface structure of the discharge chamber of the ozone generator shown in FIG. 1. FIG.

FIG. 3 is a graph of the characteristics of the total ozone decomposition amount Yd with respect to the gas residence time To of each ozone generator in the shape of A-type to C-type discharge cells.

Fig. 4 is a graph showing the characteristic of the ozone concentration Ct with respect to the specific electric power value DW/Q of each ozone generator in the shape of the A-to-C discharge chamber.

Fig. 5 is a graph showing the characteristics of the ozone concentration Ct taken out with respect to the total gas flow rate Q of the raw material gas of each ozone generator in the shape of A-type to C-type discharge cells.

FIG. 6 is a graph of the characteristic of the load peak voltage Vp applied to each ozone generator in the shape of A-type to C-type discharge cells with respect to the operating frequency f of the ozone power supply.

FIG. 7 is a graph showing the characteristic of the extracted ozone concentration Ct with respect to the ratio power value DW/Q in the conventional ozone generator.

<Embodiment>

(Principle and summary)

Fig. 1 is an explanatory diagram of the configuration of an ozone gas generating system according to an embodiment of the present invention. As shown in the figure, the ozone gas generating system 1000 of the present embodiment includes an ozone generator 200 having discharge chambers (S1 and S2: definitions) disposed on a pair of plate electrodes (1, 3a, 3b) via a dielectric substance It is a basic discharge chamber); and a power supply 100 for ozone, and an ozone generating AC voltage is applied to the ozone generator 200.

Next, a dielectric barrier discharge is generated in the discharge space of the discharge chamber (S1, S2) in the ozone generator 200, ozone gas is generated from the raw material gas containing oxygen supplied to the discharge space, and the ozone gas is taken out to the outside.

In the ozone gas generating system 1000, each unit discharge chamber has a discharge space (a space formed by a pair of discharge surfaces) and an ozone gas outlet. Hereinafter, there are cases where a pair of discharge surfaces constituting a discharge space is referred to as "a unit discharge surface" or "a group of discharge surfaces". In addition, the discharge power dw (W), discharge area so (cm ² ), raw material gas flow qo (L/min), etc. supplied to a unit discharge cell are marked with small letters as ozone gas per unit discharge cell The sign of the parameter that occurred.

On the other hand, the total discharge power DW (W), the total discharge area S (cm ² ), the total gas flow rate Q (L/min) of the raw material gas, etc. supplied to the entire plurality of discharge cells in the ozone generator 200, etc. It is marked with capital letters as the parameter symbol of the ozone generator 200. In addition, for the signs that the parameter value has not changed due to the difference of a unit discharge chamber or ozone generator, in principle, the description is marked with uppercase letters.

In order to obtain the condition that the ozone concentration Ct of the ozone generator 200 reaches the maximum, the discharge area so of the discharge shape of the discharge space and the discharge that can be put into a unit discharge space (discharge surface) in a unit discharge chamber are discussed. Optimum conditions for the power density J and the flow rate qo of the raw material gas flowing into a unit of discharge space.

Incidentally, the range of the discharge gap length d of the discharge space of the discharge chamber of the ozone gas generation system 1000 is suitable for ozone generators of tens of μm or more to less than hundreds of μm. Especially in the range where the discharge gap length d is 20 μm to 100 μm, the effect can be further improved.

When the discharge area so (cm ² ) is set within a predetermined area and is set in an ozone generator suitable for the discharge gap length d, especially as a condition for taking out a higher concentration of ozone gas, it will flow to a unit The average gas flow rate vo/d in the discharge chamber is set within a range of approximately (1.6/d) cm/s.

Moreover, the flow rate qo of the raw material gas supplied to one unit discharge cell (a group of discharge surfaces) is set to be substantially less than 0.25 L/min. Therefore, even if the specific power value dw/qo of the ozone gas generating system 1000 is set to be high, relative to the ozone gas generation amount y (=C‧qo) of a unit discharge chamber, the ozone decomposition caused by the collision of ozone gas and The total ozone decomposition amount yd of the self-decomposition of the generated ozone itself can be kept low, and a high concentration of ozone gas can be taken out from a unit discharge chamber.

Furthermore, in order to make the discharge power density supplied to a unit discharge cell in the range of 2.5W/cm ² to 6W/cm ² , by setting the discharge power dw(W), it is generated relative to the ozone gas in a unit discharge cell The amount y (=C‧qo), the total ozone decomposition amount yd, which is the sum of ozone decomposition due to collision of ozone gas and the self-decomposition of the generated ozone itself, can be kept low. As a result, the extracted ozone amount yt of ozone gas from the discharge chamber can be maximized with excellent efficiency.

In addition, the ozone gas generation system 1000 is composed of discharge chambers S1 and S2 each having a set of discharge surfaces (one discharge space) stacked in n stages to constitute the ozone generator 200. Therefore, the discharge surface (discharge space) is 2n, and the ozone gas generation system 1000 can achieve: an ozone power supply 100 that supplies 2n times the total discharge power DW (=2‧n‧dw) [W], and 2n times the total discharge area S (=2‧n‧so)[cm ² ], and the effect of 2n times the raw material gas flow rate Q(=2‧n‧qo)[L/min] Therefore, the ozone gas generating system 1000 can obtain a high-concentration extracted ozone concentration Ct from the ozone generator, and can increase the extracted ozone amount Yt of ozone gas to the maximum relative to the supplied gas flow rate Q.

In addition, the output frequency of the high-frequency high-pressure ozone generating AC voltage output from the ozone power supply 100 can be set in the range of 20 kHz to 50 kHz, which has been improved compared to the conventional output frequency of 20 kHz or less. Therefore, the ozone power supply 100 can set the peak voltage value of the ozone generating AC voltage applied to the ozone generator 200 to 7 kVp or less, and supply the total discharge power DW to the ozone generator 200.

Furthermore, by configuring the discharge surface of the discharge chamber (basic chambers S1, S2) to be circular in plan view, and reducing the diameter (outer diameter) of the discharge surface, the time for the source gas to pass through the discharge space of the discharge chamber The gas residence time To[ms] is shortened.

Moreover, by suppressing the average gas flow rate vo/d flowing into the discharge chamber to less than 0.035/d [cm/s], the gas supply amount relative to the ozone generation amount generated in the discharge chamber is also suppressed, and The high ozone generation concentration C in the discharge chamber is ensured, and the total decomposition amount Yd of ozone decomposition due to collision of ozone gas and self-decomposition of generated ozone itself can also be suppressed to be low. As a result, the ozone concentration Ct taken out from the ozone generator 200 is increased.

Furthermore, the ozone generator 200 itself, which is composed of the internal exciting inductance value Lt of the parallel resonance transformer 25 functioning as a high-frequency-high voltage transformer constituting the ozone power supply 100, and a plurality of discharge chambers stacked in multiple stages The capacitance value C0 constitutes the power supply 100 for ozone that can perform output control of high frequencies in accordance with the frequency range of parallel resonance operation.

As a result, the ozone power supply 100 becomes an ozone power supply having a parallel resonance circuit formed on the output portion of the parallel resonance transformer 25 belonging to the step-up transformer, and can supply a more stable ozone generating AC voltage to the ozone generator 200.

(Overall composition)

The configuration and features of the ozone gas generating system according to the embodiment of the present invention will be described with reference to FIGS. 1 to 6.

FIG. 1 is an explanatory diagram of the configuration of an ozone gas generating system 1000 according to an embodiment of the present invention. As shown in FIG. 1, the ozone gas generating system 1000 of the present embodiment includes an ozone generator 200 that generates ozone gas, and an ozone power supply 100 that supplies an ozone generating AC voltage for the ozone generator 200 with a total discharge power DW As the main component.

The ozone gas generating system 1000 of this embodiment is often combined with other devices such as semiconductor manufacturing equipment or cleaning equipment. In particular, high-purity ozone gas is required, and it is required to increase the processing speed or the processing capacity. Therefore, for extracting ozone gas having a higher concentration than that obtained by an existing device or the supplied gas flow rate Q, the ozone gas generating system 1000 is preferably a system for extracting a larger amount of ozone Yt.

FIG. 2 is an explanatory diagram of the discharge surface structure of the discharge chamber in the ozone generator 200 shown in FIG. 1. In FIGS. 1 and 2, the ozone gas generating system 1000 is composed of an ozone generator 200 that generates ozone gas, and an ozone power supply 100 that supplies an ozone generating AC voltage for total discharge power DW to the ozone generator 200 Posed.

The power supply 100 for ozone includes an AC-DC converter circuit section 21, an inverter circuit section 22, a current limiting reactor 23, a power supply control circuit 24, and a parallel resonance transformer 25 as main components.

The inverter circuit unit 22 belonging to the inverter unit receives power (voltage) input from a commercial power supply via the AC-DC converter circuit unit 21 and converts the voltage to a desired high frequency The high-frequency AC voltage obtained by AC is output to the parallel resonance transformer 25 via the current limiting reactor 23. In addition, the output frequency f of the high-frequency AC voltage obtained by the inverter circuit section 22 is set in the range of 20 kHz to 50 kHz. That is, the operating frequency f of the ozone power supply 100 is in the range of 20 kHz to 50 kHz.

In addition, in the specification of this case, the range indicated by "AA to BB" means in principle that AA or more does not reach BB.

The parallel resonance transformer 25 belonging to the step-up transformer boosts the high-frequency AC voltage to a high voltage to obtain an ozone generating AC voltage, and the ozone generating AC voltage is supplied to the high voltage terminal HV of the ozone generator 200 and Between low voltage terminals LV.

With the AC voltage for ozone generation, the total discharge power DW supplied to the ozone generator 200 is restricted. Furthermore, as described in detail later, the transformer 25 for parallel resonance performs measures to improve the load power.

The high-voltage terminal HV is electrically connected to the high-voltage electrodes 3 a and 3 b of each discharge cell in the ozone generator 200.

By controlling the current/voltage of the AC-DC converter circuit section 21 and the inverter circuit section 22 including a high-frequency inverter through the power supply control circuit 24, the voltage of the ozone generating AC voltage supplied to the ozone generator 200 can be supplied Value control.

The ozone generator 200 is formed by stacking a plurality of basic chambers S1 and S2 each having a basic discharge surface. The pair of basic chambers S1 and S2 is a basic structure. This basic structure is composed of a grounded cooling electrode 1 and dielectric electrodes 2a, 2b, high-voltage electrodes 3a, 3b, and insulating plates 4a, 4b.

The basic chamber S1 is composed of a stacked structure including a ground cooling electrode 1, a dielectric electrode 2a, a high-voltage electrode 3a, and an insulating plate 4a in this order from above to below.

The basic chamber S2 is composed of a stacked structure including a ground cooling electrode 1, a dielectric electrode 2b, a high-voltage electrode 3b, and an insulating plate 4b in this order from above to below. The grounded cooling electrode 1 is shared between the basic chambers S1 and S2.

Furthermore, a low-pressure cooling plate 5 is provided above the basic chamber S1 and below the basic chamber S2. The basic structure composed of a pair of basic chambers S1 and S2 having such a structure is stacked in multiple stages. In addition, a basic cell of one unit has a pair of discharge surfaces respectively forming discharge spaces. That is, when the basic structure composed of the basic chambers S1 and S2 is stacked in six stages, 12 basic chambers per unit are stacked.

The detailed structure of the basic rooms S1 and S2 will be described later. A predetermined number of basic configurations (basic chambers S1 and S2) are stacked on the base 10 in the up-down direction of FIG. 1 and become the main part of the ozone generator 200.

The plurality of stacked basic chambers is composed of a stacking pressure plate 7 stacked on the uppermost basic chamber (basic chamber S1), and a stacking chamber pressure rod 8 penetrating the stacking pressure plate 7 and each basic chamber. The base 10 is fastened with a predetermined pressing force.

The plurality of basic chambers are entirely covered with a generator cover 11. The generator cover 11 is substantially box-shaped by removing one side thereof, and the flange provided at the periphery of the opening is locked to the base 10 with a cover bolt (not shown). An O-ring (not shown) is interposed between the opening peripheral portion of the generator cover 11 and the base 10 to form a closed structure in the internal space formed by the generator cover 11 and the base 10.

The base 10 is provided with a raw material gas inlet 31 for supplying raw material gas such as high-purity oxygen gas in its internal space. The raw material gas G _IN supplied from the raw material gas inlet 31 fills the internal space in the generator cover 11 and enters the gap of the discharge spaces of the plurality of discharge cells.

The base 10 is provided with a cooling water inlet and outlet (not shown) for cooling water to enter and exit. The cooling water is used to send the ozone gas generated in the discharge space from the ozone generator 200 to the outside ozone gas outlet through the manifold box 9 32 and apply cooling to the discharge chamber.

That is, the ozone gas outlet 32 is an end opening of the ozone gas passage provided in the base 10, and the cooling water inlet and outlet communicate with the cooling water passage provided in the base 10 (not shown). In addition, the cooling water passage and the ozone gas passage provided in the base 10 are formed as independent passages.

In the ozone gas generating system 1000 having such a configuration, in order to further increase the amount of extracted ozone Yt, the discharge power DW relative to the discharge surface (total discharge area S) of a plurality of discharge cells input into the ozone generator 200 is increased. The ratio of discharge power density J (=DW/S) is restricted. In addition, in order to set the conditions to increase the ozone concentration Ct, the discharge surface diameter of a unit basic cell is reduced to limit the average gas flow rate vo/d supplied to a unit discharge cell (basic cell S1 or S2) . Through such reduction, the ozone decomposition amount yd of a discharge chamber (basic chamber) can be suppressed low, and high-concentration ozone gas can be taken out. Moreover, by dispersing the supply gas in a plurality of multi-layer stacking chamber structures (n(≧2)) formed by a plurality of discharge chambers each having basic chambers S1 and S2, the total amount of raw gas supplied 2n times the flow rate qo of the raw material gas can be supplied Gas flow rate Q (=2‧n‧qo).

In addition, when the discharge power density J (=DW/S) that can be put into each discharge chamber in the ozone generator 200 is increased, if the desired total discharge power DW is supplied, the load applied voltage Vd increases. The output frequency of the power supply for ozone 100 is increased to 20 to 50 kHz for the purpose of suppressing the load applied voltage Vd to be low and supplying the desired total discharge power DW to ensure the maximum amount of ozone to be extracted Yt. In addition, the load applied voltage Vd represents the effective value of the ozone generating AC voltage output from the ozone power supply 100.

In addition, in the ozone power supply 100, the internal magnetizing inductance value Lt of the parallel resonance transformer 25 and the electrostatic capacity value C0 of the ozone generator 200, which is composed of a plurality of discharge chambers stacked in multiple stages, can be connected in parallel. The high-frequency AC voltage of the resonant output frequency is output from the inverter circuit unit 22.

Specifically, the power supply 100 for ozone sets the operating frequency f in the vicinity of the parallel resonance frequency fc that satisfies the following equation (5).

fc=1/(2π‧(Lt‧C0) ^0.5 )...(5)

As a result, the ozone power supply 100 becomes an ozone power supply in which a parallel resonance circuit is formed on the output side of the parallel resonance transformer 25, and a more stable ozone generating AC voltage can be supplied to the ozone generator 200.

As shown in FIG. 1 and FIG. 2, when viewed from above, the peripheral end portion of the ground cooling electrode 1 partially has a manifold block 9 extending in the stacking direction of a plurality of discharge cells (S1, S2).

The ground cooling electrode 1 has an upper surface and a lower surface that are circular in plan view as discharge surfaces. That is, the upper surface of the ground cooling electrode 1 is the discharge surface of the basic chamber S1, and the lower surface of the ground cooling electrode 1 is the discharge surface of the basic chamber S2. That is, the basic chamber S1 uses the upper surface of the grounded cooling electrode 1 and the lower surface of the dielectric electrode 2a as a pair of discharge surfaces, and a discharge space is formed between the pair of discharge surfaces. Similarly, the basic chamber S2 uses the lower surface of the grounded cooling electrode 1 and the upper surface of the dielectric electrode 2b as a pair of discharge surfaces, and a discharge space is formed between the pair of discharge surfaces. The two discharge spaces are provided with openings 15 for taking out generated ozone gas. In addition, in order to cool both surfaces of the basic discharge cells S1 and S2, the ground cooling electrode 1 has a cooling water path (not shown) inside.

The opening 15 communicates with the ozone gas output path 92 of the manifold box block 9 via the output path 17 provided inside the grounded cooling electrode 1. On the other hand, the cooling water output path 91 and the cooling water input path 93 provided in the manifold block 9 are connected to the cooling water path provided inside the grounded cooling electrode 1.

In this way, the cooling mechanism for cooling the plurality of discharge chambers of the ozone generator 200 includes: a cooling water path provided on the base 10, a cooling water output path 91 and a cooling water input path provided on the manifold block 9 93, and the cooling water path provided in the ground cooling electrode 1.

Furthermore, a plurality of discharge spacers 13 for forming a discharge gap length d (mm) are provided on the upper and lower surfaces of the grounded cooling electrode 1, respectively, and the dielectric electrodes 2a and 2b and the high-voltage electrodes 3a and 3b A plurality of discharge spacers 13 overlap. As a result, a discharge space having a discharge gap length d can be formed between the ground cooling electrode 1 and the high-voltage electrode 3a (dielectric electrode 2a) and between the ground cooling electrode 1 and the high-voltage electrode 3b (dielectric electrode 2b).

In addition, as an ozone generation method, the upper surface and the lower surface of the grounded cooling electrode 1 are made of an ozone generator coated with a photocatalyst material (not shown) for generating ozone.

The raw material gas G _IN is supplied from the outer periphery of the ground cooling electrode 1. At this time, the raw material gas flow rate qo(Q/n) dispersed into the number n of the plurality of discharge cells is supplied to each discharge cell. Then, by applying an alternating voltage for ozone generation between the grounded cooling electrode 1 and the high-voltage electrodes 3a and 3b, a dielectric barrier discharge can be formed over the entire discharge surface of each discharge cell. Therefore, in the discharge space, the activation of the light energy of the dielectric barrier discharge and the activation of the photocatalyst cause the dissociation of oxygen atoms of the oxygen contained in the raw material gas supplied to the discharge space.

As a result, the ozone generator 200 can promote the three-body collision chemical reaction between oxygen atoms and oxygen generated during the pause of intermittent discharge, which is a characteristic of dielectric barrier discharge, and exerts highly efficient ozone in the discharge space of each discharge chamber Generating ability. That is, the ozone generator 200 can generate ozone gas whose concentration is proportional to the total discharge area S of the plurality of discharge cells and the specific power value DW/Q.

Since the raw material gas G _IN is supplied from the outer periphery of the ground cooling electrode 1, the ozone gas generated in the discharge space of each discharge cell will follow the flow of the gas and enter the opening 15 at the center of the ground cooling electrode 1, and then pass through The output path 17 as an ozone passage in the grounded cooling electrode 1 is taken out as the output ozone gas G _OUT .

In the ozone generator 200, the ozone gas generated by each discharge chamber is collected, passes through the ozone gas output path 92 of the manifold box block 9, and finally, the ozone gas of a predetermined concentration is taken out from the ozone gas outlet 32 to the outside.

Finally, the extracted ozone amount Yt taken out from the ozone generator 200 is the ozone gas generation amount y generated from each discharge space of a unit discharge chamber, deducting the ozone decomposition amount caused by the collision in the discharge of each discharge space, and the discharge chamber The total ozone self-decomposition amount of ozone is the total ozone decomposition amount yd and the total ozone removal amount yt.

The amount of ozone generated per unit time y (g/h) generated by each discharge cell in the second diagram is related to the flow rate of raw material gas qo (L/min) supplied to the discharge space and the discharge power dw input to each discharge cell (W) Corresponds, and is represented by the following formula (6) by the photocatalyst function applied to the discharge surface.

y=qo‧C...(6)

In equation (6), "C" is the ozone concentration (g/m ³ ) calculated from the ozone generation amount y generated per unit time of the discharge cell and the raw material gas flow rate qo in the discharge space.

That is, one discharge space volume dv (cm ³ ) belonging to the discharge space volume formed by one unit discharge cell is expressed by the following formula (7).

dv(cm ³ )=d‧so...(7)

Therefore, the amount of ozone ys(g) remaining in the discharge space after the generation of one discharge space is the discharge space volume dv(cm ³ calculated by the generated ozone generation concentration C(g/m ³ ) and equation (7) ) Product corresponds to the amount of ozone generated y.

In addition, in formula (7), "d" is the discharge gap length (cm), "so" is the discharge area (cm ² ) of the discharge surface of a unit discharge cell, these parameters "d", "so" are the limits The fixed value of the discharge cell structure.

The ozone generation concentration C (g/m ³ ) generated in the discharge cell corresponds to the discharge power dw injected into the unit gas volume dv (cm ³ ) per unit time. In addition, the unit gas volume dv can be disclosed to the following formula (8) (same as formula (2)) for a unit discharge cell again.

dv(cm ³ /sec)=1000‧Q/(n‧60)...(8)

In other words, the ozone generation concentration C (g/m ³ ) generated in a unit discharge chamber is determined by the specific power value dw/qo (W‧min corresponding to the discharge energy (joule/cm ³ ) injected into the unit gas volume dv /L), as shown in the following equation (9), the amount of ozone remaining in the discharge space ys(g) increases proportionally to the specific power value dw/qo(W‧min/L).

ys(g)=C‧d‧s/1000000...(9)

Here, although the specific power value of a unit discharge cell is expressed by dw/qo, in the case of multi-layer stacking, the (n times) overall specific power value DW/Q is also expressed by the same ratio. Power value DW/Q said.

However, in the actual discharged ozone gas generating device, as shown in FIG. 7, the extracted ozone concentration Ct does not increase in proportion to the specific power value DW/Q, and the characteristic of the extracted ozone concentration Ct relative to the specific power value DW/Q It is characteristic 8000a.

In characteristic 8000a, the tangent (two-point chain line) of the extracted ozone concentration Ct characteristic of the low specific power value DW/Q is defined as the characteristic of the ozone generation concentration C (g/m ³ ) generated in the discharge chamber (ozone generation chamber) .

On the other hand, as shown by characteristic 8000a in FIG. 7, the extracted ozone concentration Ct in the high specific power value DW/Q area can be determined as the ozone generated in each discharge chamber subtracted from the ozone generation concentration C generated in each discharge chamber The value after decomposing the concentration Cd.

As shown in FIG. 7, in the large flow rate region where the raw material gas flow rate Q is approximately 3.0 L/min or more, the characteristic of the ozone concentration Ct taken out relative to the specific power value DW/Q in the ozone generator Sex 8000a is saturated with a predetermined concentration value. Therefore, even if the total discharge power DW is increased and the specific power value DW/Q is increased, the extracted ozone concentration Ct cannot be increased.

Even if the specific power value DW/Q is increased, the extracted ozone concentration Ct does not increase from the predetermined concentration value, but shows a tendency to decrease because the electrons, ions, and discharge gas generated in the discharge chamber are generated in the discharge space. Ozone collides and decomposes the ozone gas, and the ozone detained in the discharge chamber itself decomposes greatly.

That is to say, when the ozone gas generated in the discharge space passes through the electron space in the discharge, the decomposition amount due to collision with electrons, ions, discharge gas, etc. and the self-decomposition amount of ozone self-decomposition are very large. , Will reduce the ozone concentration Ct.

The total ozone decomposition amount Yd (=2‧n‧yd) of ozone decomposition in the discharge chamber depends on the amount of electrons ne generated in the discharge space, the molecular weight of the discharge gas ng, the average gas flow rate vo/d, the gas residence time To and the gas temperature Tg, which can be expressed by the following formula (10). In addition, "yd" means the amount of ozone decomposition per unit discharge chamber.

Yd=B(ne, ng, vo/d, To, Tg, C)...(10)

As shown in equation (10), the total ozone decomposition amount Yd is obtained as a function of B(...).

Therefore, if the total ozone decomposition amount Yd of ozone gas decomposition in a plurality of discharge chambers can be reduced corresponding to the specific power value DW/Q, the ozone concentration Ct can be increased.

The total ozone decomposition amount Yd of the ozone decomposition in the plurality of discharge chambers is the amount of ozone gas decomposition in the plurality of discharge spaces, but as shown in FIG. 7, in the large flow rate region where the total gas flow rate Q is approximately 3.0 L/min or more In this case, the ratio of the total discharge power DW input to generate ozone gas and the gas flow rate Q (specific power value DW/Q) is determined univocally.

From this situation, it can be seen that the total ozone decomposition amount Yd depending on the specific power value DW/Q has an inherent characteristic determined by the structural conditions of the ozone generator itself. This means that if generated from ozone If the structure of the device or the output condition of the ozone power supply is reexamined, the total ozone decomposition amount Yd depending on the specific power value DW/Q can also be reduced, and the extracted ozone amount Yt can be increased. This case is an invention focusing on this point.

In the cross section of one discharge surface of the grounded cooling electrode 1 shown in FIG. 2, pay attention to the ozone decomposition amount of the ozone gas generated in the discharge chamber.

When the raw material gas is supplied at the raw material gas flow rate Q (the raw material gas flow rate), the raw material gas flow rate qo (=Q/(2‧n)) that is supplied to each of the 2n one-unit discharge cells (basic chambers S1 or S2) is dispersed and supplied. , And consider the situation of the discharge power dw (=DW/(2‧n)) put into each unit discharge chamber

In this case, the ozone generation amount y[=Y/(2‧n)] (g/h) of the ozone gas generated in one discharge space is the amount generated by flowing the raw material gas through the discharge space. Moreover, the amount of ozone generated by a unit of discharge chamber y is closely related to two elements, including the gas residence time To belonging to the time passing through the discharge space, and the unit perimeter l flowing to a group of discharge surfaces (cm) is the average gas flow rate vo/d(cm/s) (=qo‧0.001/(60‧sav)) of the gas profile sav (=l‧d) of the discharge chamber. These two elements are inherent values determined by the shape of the discharge cell. In addition, the unit perimeter 1 (cm) refers to the perimeter (cm) along the outer side of the representative discharge surface belonging to one discharge surface among a pair of discharge surfaces forming one discharge space. That is to say, the perimeter (cm) of the discharge diameter of the average area sav (=so/2) of a discharge surface is the unit perimeter l (cm).

The gas residence time To is closely related to both the amount of ozone decomposition caused by the collision of electrons, ions, discharge gas and ozone gas generated on the discharge surface of the discharge space, and the self-ozonolysis amount of ozone remaining in the discharge space. In addition, the average gas flow rate vo/d (cm/s) based on the unit perimeter l (cm) is closely related to the ozone generation capacity generated in a unit discharge chamber. Compared with the ozone generation capacity, the average gas flow rate of the gas The greater the vo/d, the greater the total gas flow Q, and the lower the ozone concentration taken out.

Therefore, the gas residence time To and the gas temperature Tg are factors that increase the amount of decomposition due to the collision of ozone gas in the discharge space and the self-decomposition amount of ozone itself, and are the main factors contributing to the increase in the amount of ozone decomposition in the discharge chamber. Furthermore, when the average gas flow rate vo/d (cm/s) is increased compared to the ozone generation capacity in the discharge space, the ozone concentration Ct taken out will decrease.

That is to say, in a discharge space, the ozone generation amount y[=Y/(2‧n)] of ozone gas generated by the discharge energy density J(=wd/so) with dielectric barrier discharge energy g/h), regarding the ozone amount ys(g) remaining in the discharge space, when the ozone amount ys is taken out of ozone at a high concentration, the ozone decomposition amount yd in the discharge space due to the gas residence time To of the gas The impact cannot be ignored.

Specifically, the greater the gas residence time To, the longer the ozone decomposition time, and the greater the ozone decomposition amount yd, which is the sum of the decomposition amount due to the collision with the discharge gas and the self-decomposition amount of the retained ozone itself.

Furthermore, when the average gas flow rate vo/d (cm/s) is increased compared to the ozone generating capacity in the discharge space, the extracted ozone concentration Ct will decrease.

Furthermore, when the discharge power density J increases, although the gas temperature Tg tends to increase, if the entire discharge surface is cooled and there is cooling capacity to sufficiently remove the discharge heat energy, the ozone decomposition amount yd will not After the discharge power density J that can be input increases, the shape of the discharge chamber increases, but it can be suppressed by a certain degree of cooling capacity.

The ozone decomposition due to the gas temperature Tg is related to the cooling capacity of the discharge electrode surface, and it is possible to suppress the temperature rise of the gas temperature Tg by forming a sufficient cooling capacity. Regarding the suppression of the temperature rise of the gas temperature Tg, it is a necessary issue in the design of the ozone generator. Here, the increase in the amount of ozone decomposition caused by the gas temperature Tg is not considered.

Next, when a large flow rate of raw material gas of generally 3.0 L/min or more is circulated, the gas residence time To in the discharge space flows through the discharge based on the unit circumference l (cm) Consider the average gas flow rate vo/d in the space and the shape of the discharge chamber suitable for the discharge power density J. The gas residence time To is represented by the following formula (11).

To(ms)=(d‧so)/qo...(11)

In addition, in formula (11), "d" is the discharge gap length (mm), "so" is the discharge area (cm ² ) of the discharge surface in a unit discharge chamber, and "qo" is the raw material gas flow rate in each discharge space (L/min).

On the other hand, "S" means the total discharge area (cm ² ) in the ozone generator 200, "Q" means the total gas flow rate (L/min) of the raw material gas supplied into the ozone generator 200, "n" It shows the number (number) of stacked discharge chambers (combination of basic chambers S1 and S2) of the ozone generator 200 shown in FIG. 1, and the number of discharge surfaces is 2‧n.

Furthermore, the average gas flow rate vo/d (cm/s) to the discharge surface based on the unit perimeter l (cm) depends on the shape of the discharge cell. For example, in the case of a disc-shaped discharge cell, the gas profile sav flowing into the discharge cell based on the unit perimeter l (cm), if the inflow discharge area so corresponds to 1/2 of the discharge diameter per unit gap length When the average gas flow rate vo is defined, it is expressed by the following formula (12).

vo(cm/s)=qo/(2π‧(so/2π) ^0.5 )=f(so)‧{1/To}...(12)

In addition, the average gas flow rate vo per unit gap length is a reciprocal value that depends on the function f(so) and the gas residence time To in the discharge space.

In addition, the discharge power density J (W/cm ² ) that can be put into one discharge space is expressed by the following formula (13).

J(W/cm ² )=DW/S=dw/so...(13)

In addition, in equation (13), "DW" is the total discharge power.

In the discharge space, the element whose ozone decomposition amount yd simply increases proportionally is the gas residence time To. In order to shorten the gas residence time To, if the discharge area so of the discharge surface of a unit discharge cell is reduced, and the same discharge power dw[=DW/(2‧n)] is input, it can be expressed as formula (11) The degree of shortening the gas residence time To decreases the ozone decomposition amount yd.

However, when the discharge area so of a unit discharge cell is reduced, as shown in equation (12), the average gas flow rate vo/d (cm/s) flowing through the discharge surface based on the unit perimeter l (cm) will change Big. Therefore, even under the condition that the flow rate qo of the raw material gas supplied into the discharge surface is low, the ozone extraction concentration Ct can be increased.

The inventor of the present application found that, if the discharge area so of a unit discharge cell is reduced, it is important to set the conditions for shortening the gas residence time To in the discharge space under the condition that the flow rate qo of the raw material gas supplied to the discharge space is low. That is, the inventors of the present invention understood that by setting the above conditions, it is possible to shorten the time required for the decomposition including ozone decomposition due to collision of ozone generation and the self-decomposition of retained ozone itself, and as a result, the ozone in the discharge space can be made The decomposition amount yd decreases.

Therefore, in order to be able to take out high-concentration ozone, it is preferable to set the average gas flow rate vo/d to an optimal condition to shorten the gas residence time To. That is to say, in order to reduce the ozone decomposition amount yd when the ozone generated in the discharge space is taken out, it is necessary to reduce the discharge area so of one unit discharge chamber.

Next, as a method of shortening the gas residence time To, it is possible to consider reducing the diameter of the discharge surface of the discharge chamber so that the discharge power density J is within an ideal range, and set the discharge power dw to be input into the discharge space formed by the discharge surface having a reduced diameter Methods. According to this method, the ozone decomposition amount yd of one discharge space can be reduced, and as a result, a predetermined amount of ozone gas can be taken out of one discharge space at a higher concentration.

That is to say, as a means of taking out high-concentration ozone gas, the inventor of the present invention will include: so), to limit the setting of the discharge power density J, the discharge power dw put into one discharge space, and the raw gas flow qo to make the average gas flow rate vo/d within the regulation range Appropriate setting is very important.

In addition, as a method for increasing the gas flow rate at which the high-concentration ozone gas is taken out while maintaining the conditions regarding the above-mentioned one discharge space, a method of stacking the discharge chambers having the basic chambers S1 and S2 in multiple stages (n times) is expected. If the discharge chambers are stacked in n sections, an ozone gas generation system with an increased discharge power DW (=2‧n‧dw) and total gas flow Q (=2‧n‧qo) can be formed. As a result, high-concentration ozone gas can be taken out in a larger gas flow area.

In addition, in the ozone gas system configured as described above, by setting the total discharge power DW (=2‧n‧dw) and the total gas flow rate Q to the maximum possible range, the extracted ozone amount Yt(=Ct‧Q ) Increase to the maximum.

As described above, in order to be able to take out high-concentration ozone, the means for reducing the ozone decomposition amount yd can shorten the gas residence time To in the discharge space, so the discharge area so of a group of discharge surfaces is reduced to within the range of the regulatory limit The ozone gas generation system is ideal.

In addition, since the extracted ozone amount Yt can be increased, it is ideal to apply an optimized ozone gas generating system within the limits of the total discharge power DW and discharge power density J.

Secondly, as an ozone gas generating system that can take out high-concentration ozone, although there are means for lowering the gas flow rate or cooling the ozone generator to a lower temperature, it is limited to areas where low-flow ozone gas is required. In addition, the means for cooling the ozone generator to a lower temperature will increase the auxiliary equipment of the ozone gas generation system, and the ozone gas generation system itself will be more expensive and larger than the conventional device.

It can be considered from the above facts: the limitation condition of the ozone gas generating system that takes out high-concentration ozone is a large flow type gas flow rate with a total gas flow rate Q of a gas flow rate range of about 3.0 L/min or more, and the ozone generator 200 is cooled The cooling temperature is set under the condition of 5 ℃ or more. Under this condition, it is necessary to realize, for example, an ozone gas generation system 1000 that can take out high-concentration ozone of 400 g/m ³ or more as an example, and can take out an increased amount of extracted ozone Yt. In this case, it is not only necessary to secure the total discharge area S of the ozone generator 200, but to obtain the stable ozone power supply 100 that can set the discharge power density J and the total discharge power DW supplied to the discharge space to the maximum possible range. Very important.

In order to obtain a high concentration and a predetermined amount of ozone gas, the ozone power supply 100 must input the total discharge power DW to the ozone generator 200 and increase the discharge power density J of the ozone generator 200. In this case, if the output voltage of the ozone generating AC voltage of the power supply 100 for ozone is less than 20 kHz of the conventional output frequency, the load voltage applied to the ozone generator 200 will increase, and the power supply 100 for ozone and the ozone generator The 200 withstand voltage must be strengthened and other issues.

Therefore, as the power supply 100 for ozone that applies a load applied voltage Vd with a peak voltage of 7 kVp (5.0 kVrms) or less, a high-frequency type ozone generating AC voltage with an output frequency f of 20 kHz to 50 kHz (20 kHz or more but less than 50 kHz) is preferable Power supply for ozone. In addition, when an ozone power supply with an output frequency f exceeding 30 kHz is used, the noise emitted by the power supply itself will increase sharply, and the malfunction of the measuring instrument or external device attached to the ozone gas generating system will increase. Furthermore, in order to maintain the ozone generator and the load near the resonance frequency, frequency control in response to load fluctuations at the output frequency f is indispensable, and it is very difficult for the ozone power supply to output stable power. Therefore, the output frequency f of the ozone power supply 100 is preferably limited to 20 kHz to less than 30 kHz.

The following two power sources can be considered for the power supply for ozone that applies a voltage Vd of 20 kHz to 50 kHz high frequency load application.

The first power supply: a power supply with a series resonance circuit between the inverter portion of the ozone power supply and the ozone generator; the second power supply: a high frequency-high voltage between the inverter portion of the ozone power supply and the ozone generator Transformer power supply.

In the first power supply, it is necessary to cancel the transformer on the output side of the power supply for ozone, and to provide a series resonance circuit with a high resonance Q value (for example, a Q value of 10 or more) between the inverter section and the ozone generator, and boost it to the load The voltage Vd is applied. The first power supply has the advantage of eliminating the need for high-frequency and high-voltage transformers, and the power supply for ozone can be simplified.

However, the first power supply must resonate between the three main components including the inverter, the series resonance circuit, and the ozone generator. The feedback current due to the resonated load current returns to the inverter, causing The power loss of the inverter part becomes very large.

Furthermore, since the first power supply will boost resonance to the load applied voltage Vd, the load applied voltage Vd changes due to subtle load condition fluctuations, and even if the operating frequency of the inverter section is controlled, it is difficult to put a stable Load applied voltage Vd. Moreover, because the operating frequency is often variable, there is a problem that the power supply noise becomes larger.

Due to the above problems, in practice, the discharge power DW output from the high-frequency ozone power supply is only applicable to ozone gas generating systems that do not reach 1.5 kW. In addition, the installation of a plurality of small ozone power sources belonging to the first power source causes the complexity of the ozone generator or the complexity of the control, and thus causes problems such as loss of control in the power source for ozone and an increase in the number of parts.

Therefore, when the gas flow rate range of the total gas flow rate Q (source gas flow rate) of the raw material gas is set to approximately 3.0 L/min or more, and the cooling temperature for cooling the ozone generator is set at 5° C. or more, 400 g is taken out. The ozone gas generating system of this embodiment for the purpose of high-concentration ozone gas of /m ³ or more is not suitable. The reason is that the ozone gas generating system of the present embodiment must satisfy the total discharge power DW with a specific power value DW/Q of 600 W‧min/L or more.

In the second power supply, by providing a high frequency-high voltage transformer (parallel resonance transformer 25) between the inverter part (inverter circuit part 22) and the ozone generator, the primary side of the high frequency-high voltage transformer can be used A fixed value determined by the turns ratio of the number of windings to the number of secondary windings increases the voltage. Furthermore, after the secondary side of the transformer, by providing a parallel resonance circuit with the load, the The output frequency and the load applied voltage Vd are set at approximately constant values, and then the total discharge power DW is supplied to the ozone generator 200.

As a result, the resonant load current will not return to the inverter part as a feedback current, the power loss of the inverter part is small, and will not be affected by the degree of resonance with the load, the load applied voltage Vd can be kept fixed, and the load is supplied to the load Stable total discharge power DW.

Therefore, in the second power supply, the discharge power DW output from the high-frequency ozone power supply can be set to 1.8 kW or more, and the second power supply has an advantage that a stable output can be input to the ozone generator.

The power supply 100 for ozone of this embodiment can satisfy the requirements of the above second power supply. Therefore, the ozone gas generating system 1000 can be constituted by a combination of the ozone power supply 100 and the ozone generator 200.

Therefore, the ozone gas generating system 1000 of the present embodiment can set the gas flow rate range of the total gas flow rate Q of the raw material gas to approximately 3.0 L/min or more, and the cooling temperature of the cooling ozone generator 200 to be set to 5° C. or more. , remove 400g / m ³ or more high-concentration ozone. Moreover, the ozone gas generation system 1000 can be a high-concentration ozone gas extraction flow rate that can be increased, and the cooling capacity of the ozone generator can also reach an ozone gas generation system of the same level as in the past.

In addition, in order to form the resonance frequency of the internal inductance of the parallel resonance transformer 25 itself and the electrostatic capacity of the load (ozone generator 200), the operating frequency of the inverter circuit section 22 is set. Therefore, it is not necessary to newly install a resonance reactor on the output side of the parallel resonance transformer 25, and there is an advantage that the resonance circuit after the secondary side of the parallel resonance transformer 25 can be shared by the parallel resonance transformer 25.

The above is an ozone generator means for extracting high-concentration ozone gas from the raw material gas at a large total gas flow rate Q, setting the discharge space of a unit discharge chamber in the generator at The importance of the optimal range is explained. The ozone gas generating system 1000 of this embodiment will be described in detail below with reference to FIG.

The total discharge power DW input from the ozone power supply 100 is set at a fixed 5.0 kW, the number n of discharge chamber segments of the ozone generator 200 having the basic chambers S1 and S2 is set to 6 (a total of 12 discharge spaces can be formed), and the discharge gap The length d is set at a fixed length that can satisfy the conditions of tens to hundreds of μm, and the following three types of ozone generators are prepared.

Type A discharge chamber shape generator...total discharge area S is 2500cm ²

Type B discharge chamber shaped generator...total discharge area S is 1250cm ²

Generator with C-shaped discharge cell shape...total discharge area S is 625cm ²

Then, the ozone concentration to be taken out was obtained from the generators of the A-type discharge cell shape to the generators of the C-type discharge cell shape, respectively.

170(mm)，可投入的放電電力密度J為2W/cm²。 In the generator of type A discharge cell, a discharge area so is set to about 209 cm ² , and the discharge diameter (diameter of the discharge surface) is about

170 (mm), the discharge power density J that can be input is 2 W/cm ² .

115(mm)，可投入的放電電力密度J為4W/cm²。 In the generator of the B-type discharge cell shape, a discharge area so is set to about 104 cm ² and the discharge diameter is about

115 (mm), the discharge power density J that can be input is 4 W/cm ² .

81(mm)，可投入的放電電力密度J為8W/cm²。 In the generator of the C-shaped discharge chamber, a discharge area so is set to about 52 cm ² , and the discharge diameter is about

81 (mm), the discharge power density J that can be input is 8 W/cm ² .

In addition, the cooling water temperature for cooling the ozone generator is set at a fixed 5°C.

As shown in Fig. 2, by setting the discharge diameter of a set of discharge surfaces to be smaller, the gas residence time To of one discharge space is relative to the discharge power density J that can be put into one unit discharge chamber (basic chamber S1 or S2) The increase rate is doubled for generators in the shape of A-type discharge cells, 1/2 for generators in the shape of B-type discharge cells, and 1/4 for generators in the shape of C-type discharge cells.

By setting the number n of discharge cells to 6 (the number of discharge surfaces is 12 (the number of discharge spaces is 12)), the average gas flow rate vo/d of a unit discharge cell is 1/ in the shape of the generator of type A discharge cell 12. The generator in the shape of the B-type discharge chamber is 1/6, and the generator in the shape of the C-type discharge chamber is 1/3. Therefore, with respect to the increasing ratio of the discharge power density J, the flow velocity of one discharge space in each type of generator, the average gas flow velocity vo/d can only be 1/n of the corresponding number n of discharge cells (the number of discharge surfaces 12) The proportion of 12 increases.

As a result, it can be explained that the total ozone decomposition amount Yd when the ozone gas generated in the ozone generator 200 passes through the discharge space is reduced in the discharge chamber where the discharge diameter is small. The details of the high-concentration ozone gas extraction effect with respect to the shape of a unit discharge cell and the discharge cell stacking will be described later.

FIG. 3 shows the ozone generator 200 of the present embodiment in the case of a generator of A-type discharge chamber shape, a generator of B-type discharge chamber shape, and a generator of C-type discharge chamber shape, the total ozone decomposition amount Yd is relative to Characteristic curve of the gas retention time To in the discharge space when the raw material gas flows to each discharge surface.

In Figure 3, the characteristics of the total ozone decomposition amount Yd of the A-type discharge chamber shape generator is 5000a, and the characteristics of the total ozone decomposition amount Yd of the B-type discharge chamber shape generator is 5000b, and the generation of the C-type discharge chamber shape The characteristic of the total ozone decomposition amount Yd of the device is 5000c.

In addition, the characteristic 5000s1 indicated by the dotted line indicates the upper and lower limits obtained by exploring the boundary value set by the discharge power density J.

The characteristic 5000s1 is the boundary characteristic between the discharge power density J of the generator of the A-type discharge cell shape and the generator of the B-type discharge cell shape, which corresponds to 2.5 W/cm ² .

The characteristic 5000s2 is the boundary characteristic of the discharge power density J between the generator of the B-type discharge chamber shape and the generator of the C-type discharge chamber shape equivalent to 6.0 W/cm ² .

The characteristics 5000a, 5000b, and 5000c shown in Fig. 3 are compared. As shown in Figure 3, if the discharge diameter is reduced, the gas residence time To is within the range of 50 ms or less, The total ozone decomposition amount Yd will increase by a certain proportion corresponding to the gas residence time To. On the other hand, in the range where the gas residence time To is 50 ms or more, it has been experimentally confirmed that the smaller the discharge diameter, the smaller the total ozone decomposition amount Yd.

That is, if the discharge diameter of the discharge surface is set to a smaller condition, the amount of ozone decomposition yd in the discharge space will decrease, and it means that the amount of ozone Yt taken out from the ozone generator 200 will increase according to the degree of reduction. In this regard, the C-shaped discharge cell shape generator is the most excellent.

The region 99a indicated by the chain line corresponds to the total ozone decomposition amount Yd of the high concentration ozone gas in the extraction range, and the content thereof will be described later. As shown in FIG. 3, in the range of the gas residence time To of the discharge space from 20 ms to 80 ms, the total ozone decomposition amount Yd of the region 99a has been suppressed to about 400 g/h to 900 g/h, compared to the total of the characteristic 5000a The ozone decomposition amount Yd has been sufficiently reduced, so it can be expected to take out a high concentration of ozone gas.

Fig. 4 is a characteristic curve of the extracted ozone concentration Ct against the specific power values DW/Q of the generators of the A-type discharge cell shape, the B-type discharge cell shape, and the C-type discharge cell shape.

Figure 4 shows the characteristic 4000a of the ozone extraction concentration Ct of the generator of the A-type discharge chamber, the characteristic 4000b of the ozone extraction concentration Ct of the generator of the B-type discharge chamber, and the ozone of the generator of the C-shaped discharge chamber shape Take out the characteristic 4000c of concentration Ct.

In addition, the characteristics 4000s1 and 4000s2 shown by the dotted lines are the same as those in Fig. 3, and show the upper and lower limits obtained after the discharge power density J can be set to the maximum boundary value of the shape of the discharge chamber within the possible range.

The characteristic 4000s1 shows the characteristic result of the lower limit of the shape of the discharge cell in which the discharge power density J at which the ozone concentration Ct is 400 g/m ³ is obtained. The discharge power density J is a discharge cell shape that can be set to about 2.5 W/cm ² .

The characteristic 4000s2 shows the characteristic result of obtaining the upper limit boundary of the discharge cell shape for the discharge power density J at which the ozone concentration Ct is 400 g/m ³ , and the discharge power density J is the shape of the discharge cell that can be set to about 6.0 W/cm ² .

Although the characteristic of the extracted ozone concentration Ct is the ozone generation concentration of the discharge space showing the reaction specific power value DW/Q, the characteristic of the extracted ozone concentration Ct in the case of a discharge chamber shape with a different discharge power density J that can be put into the ozone generator Also different.

However, in the ozone generators of type A to type C with various characteristics (4000a, 4000b, 4000c), the characteristics of the specific power value DW/Q from the fourth graph corresponding to the ozone generation concentration (two-point chain line) From the perspective of the inclination of the tangent characteristic), the smaller the discharge diameter of the discharge surface is, the smaller the discharge cell shape that can increase the discharge power density J is. In other words, it is shown that the shape of the discharge chamber that can increase the discharge power density J has a small ozone generation capacity in the discharge space.

The characteristics 4000a, 4000b, and 4000c shown in Fig. 4 show the results of subtracting the decomposition amount of ozone gas from the ozone generation concentration characteristics. The decomposition amount of ozone gas is the amount of ozone decomposition caused by the collision of ozone gas with electrons ne, ions n ⁺ or discharge gas ng in the discharge and the self-decomposition amount of ozone remaining in the discharge Sum.

The ozone generation concentration characteristic is a tangent characteristic that belongs to the characteristic relative to the specific power value DW/Q. It has the largest generator in the shape of the A-type discharge chamber, and the smaller the discharge chamber diameter, the greater the discharge power density J that can be input. The ozone generation concentration characteristic shows a lower tendency.

This means that the ozone generating capacity is inversely proportional to the discharge power density J. Ozone generating capacity due to the catalytic action of nitrogen in the discharge space or the photocatalyst action of the discharge surface shows a tendency to decrease as the shape of the discharge chamber increases the discharge power density J.

However, as shown in FIG. 3, in the ozone generator in which the discharge chamber with the changed discharge diameter is stacked in multiple stages, when the discharge diameter is reduced, the gas residence time To in the discharge space can be shortened, and the amount of ozone generated can be reduced. . The reason is that the decomposition system of ozone gas occurs in the discharge The period when ozone gas collides with electrons or discharge gas in the space and stays in the discharge chamber. Therefore, the self-decomposition of the generated ozone itself and the total decomposition amount due to collision can be simply reduced by shortening the gas residence time To.

Based on the above important factors, the characteristics of the ozone concentration Ct of the generator of the A-type discharge cell shape, the generator of the B-type discharge cell shape, and the generator of the C-type discharge cell shape will be different, as shown in Figure 4 In the region 99a, a high-concentration ozone of 400 g/m ³ or more can be taken out in the generator of the B-type discharge cell shape.

That is to say, in the generator of the A-shaped discharge chamber, the amount of ozone generated is high, but due to the long gas residence time To, the amount of ozone decomposition is the sum of the decomposition due to collision and the self-decomposition of ozone itself. As a result , Showing that only ozone gas with a concentration of less than 400g/m ³ can be taken out.

In the generator of the shape of the B-type discharge chamber, the amount of ozone generated is lower than that of the generator of the shape of the A-type discharge chamber, but because the gas residence time To is shortened, it belongs to the ozone decomposition which is the sum of the decomposition due to collision and the self-decomposition of ozone itself The amount is smaller. Therefore, as a result, the B-type generator was able to take out high-concentration ozone of 400 g/m ³ or more in the range of the specific power value DW/Q of 600 W‧min/L or more.

The present invention is to find the shape and operating conditions of an ozone generator discharge chamber that can take out high-concentration ozone like a B-type discharge chamber shape generator. The inventor of the present invention has found an ideal element that satisfies the following requirements.

When the total gas flow rate Q of the raw material gas supplied to the ozone generator 200 is set to about 3.0 L/min or more, the total discharge power DW input from the ozone power supply 100 must input at least 1.8 kW of power.

In addition, in the generator of the C-type discharge chamber shape, the discharge power density J is increased in order to input the predetermined discharge power DW, so that the ozone generating capacity from the discharge space (two-point chain) Line) determines that the amount of ozone generated is extremely reduced. Therefore, by shortening the gas residence time To, even if the amount of ozone decomposition which is the sum of the decomposition caused by collision and the self-decomposition of ozone itself is reduced, the ozone concentration Ct taken out is still low.

As a result, in the generator of the C-type discharge cell shape, it has been determined that the maximum gas flow rate Q of the raw material gas and the input discharge power DW can only be extracted at a concentration of less than 320 g/m ³ .

Thus, the following result is obtained: an ozone generator capable of taking out high-concentration ozone of 400 g/m ³ or more has an optimal shape of the discharge chamber, and the ozone generator of the embodiment has an upper limit of the shape of the discharge chamber In terms of range, as shown by the boundary characteristic 4000s2, the discharge power density J is preferably limited to less than about 6W/cm ² ; as for the lower limit of the discharge power density J, as shown by the boundary characteristic 4000s1, the discharge power density J It is preferable to set it at about 2.5 W/cm ² or more.

Fig. 5 is a graph showing the characteristics of the ozone concentration Ct with respect to the total gas flow rate Q of the raw material gases in the generator of the A-type discharge cell shape, the B-type discharge cell shape and the C-type discharge cell shape Figure.

In FIG. 5, characteristic 3000a shows the generator characteristics of the A-type discharge cell shape, characteristic 3000b shows the generator characteristics of the B-type discharge cell shape, and characteristic 3000c shows the generator characteristics of the C-type discharge cell shape.

The area 99a belonging to the characteristic box indicates a gas flow rate area where high concentration ozone with an ozone concentration of 400 g/m ³ or more can be taken out. In the generator of the B-type discharge chamber shape, the total gas flow rate Q of the supplied raw material gas is known Less than about 25L/min, high concentration ozone gas above 400g/m ³ can be obtained.

Furthermore, the characteristic box 99b shows that the ozone concentration characteristic 3000a obtained by the generator of the A-type discharge chamber equivalent to the conventional ozone generator can obtain a higher concentration of ozone In the gas flow rate area of the gas, in the generator of the B-type discharge chamber shape, it is known that the total gas flow rate Q of the supplied raw material gas is less than 50 L/min to obtain a high-concentration ozone gas.

In addition, in FIG. 5, when the total gas flow rate Q of the supplied raw material gas is less than 3.0 L/min, a high-concentration ozone gas of 400 g/m ³ or more can be obtained in the generator of the A-type discharge cell shape. However, in this case, the total amount of ozone that can be taken out is less than 100g/h, and there are few markets that require a small amount of ozone. Moreover, since the present ozone generator aims to take out a large flow of ozone gas and obtain a high concentration of ozone gas, the result of obtaining a low concentration of high concentration ozone gas is beyond the objective of this case.

Furthermore, it is possible to consider a generator with a shape of A-type discharge chamber as a special ozone generator, setting the cooling temperature of the generator to less than 5°C and obtaining high-concentration ozone gas of 400 g/m ³ or more. However, the generator whose cooling temperature is set to less than 5°C needs additional equipment to improve the cooling capacity, and lacks practical advantages. Therefore, in this embodiment, as the ozone gas generating system 1000, the applicable temperature of the cooling temperature is set to 5 ℃ above.

The ozone generator 200 applies an alternating voltage between the grounded cooling electrode 1 and the high-voltage electrodes 3a and 3b in each discharge chamber to cause a discharge phenomenon in the discharge space into which the raw material gas containing oxygen is injected to generate ozone gas.

An ozone generating AC voltage is applied to the high voltage terminal HV of the power supply unit of the high voltage electrodes 3a and 3b from the transformer 25 for parallel resonance of the power supply 100 for ozone shown in FIG. The total discharge power DW is regulated by the ozone generating AC voltage.

As a result, a dielectric barrier discharge can occur via the dielectric electrodes 2a and 2b in the discharge space of each discharge cell (the basic cell S1 or the basic cell S2). At this time, based on the total discharge power DW, the power density of the discharge power density J (=DW/S) (W/cm ² ) that can be put into each discharge cell is put into the discharge cell. The ozone gas generated in the discharge space of each discharge cell is collected from the opening 15 provided in the center of the discharge space to the manifold box block 9 through the output path 17 in the grounded cooling electrode 1 to output the ozone gas Path 92 and take it out of the ozone generator 200.

The ground cooling electrode 1 and the low-pressure cooling plate 5 are provided with a cooling space (not shown) for cooling, and the cooling water is output through the cooling water path provided in the base 10 and the cooling water of the manifold block 9 by cooling water The path 91 and the cooling water input path 93 flow into the grounded cooling electrode 1 and the low-pressure cooling plate 5 to cool each discharge chamber. In this way, it includes the grounded cooling electrode 1, the low-pressure cooling plate 5, the base 10, and the manifold box block 9, that is, a cooling mechanism that cools the discharge chamber to a predetermined cooling temperature.

Hereinafter, the shape of a group of discharge surfaces of a unit discharge cell will be described, and the effect of stacking a plurality of discharge cells will be further described.

In the ozone gas generating system 1000, the conditions for extracting high-concentration ozone gas from the discharge chamber having the basic chambers S1 and S2 in multiple stages (six stages) are stacked (discharge surface: 12 surfaces).

Here, in order to make the application scope of the invention of the present invention more clear, the high-concentration ozone gas extraction conditions of one discharge space of a unit discharge cell will be described. The following is the discharge of ozone gas with a higher concentration (equivalent to 400g/m ³ or more) in the large flow rate range for the total gas flow rate Q (raw gas flow rate) of the raw material gas in the large flow rate range of approximately 3.0L/min or more The chamber stacking effect will be explained.

In order to extract the ozone concentration Ct characteristic from the stacked ozone generator with respect to the total gas flow rate Q shown in FIG. 5, a high concentration of a predetermined amount of ozone gas is extracted with excellent efficiency, preferably set to a set of discharge surfaces The shape of the discharge cell with a reduced discharge area so that the flow rate qo of the raw material gas supplied to a unit discharge cell (a group of discharge surfaces) satisfies a weak range of about 0.5 L/min to about 2.5 L/min.

That is, in order to remove the high-concentration ozone gas in the region of high gas flow, and a number taken to increase the unit discharge cells are stacked as many sections n means that a discharge area so set to about 30cm ² to about 160cm ² is important. In addition, in the total gas flow rate Q of the raw material gas, in order to obtain a high-output extracted ozone amount Yt, a unit discharge chamber in which the discharge diameter of the discharge surface is reduced to limit the discharge area so is stacked in multiple stages (the number n increase) means, and preferably the discharge power density is set into the J ozone gas generating system 1000 in the range of from about 2.5W / cm ² to about 6.0W / cm ² in.

Next, the discharge power dw (=so‧J) is obtained from one discharge area so and the discharge power density J, and the flow rate qo of the raw material gas supplied to one discharge space whose discharge gap length d is set to tens to hundreds of μm is In the weak range of about 0.5L/min to about 2.5L/min, consider the case of using the shape of the B-type discharge cell. In this case, high-concentration ozone with an ozone concentration exceeding 400 g/m ³ can be taken out, and the flow rate of taken-out ozone is increased in proportion to the number n of the multi-stage stack. In addition, in the shape of the B-type discharge chamber, it is preferable that the above-mentioned condition is satisfied in order to obtain the extracted ozone amount Yt in the maximum possible range of the total gas flow rate Q, and from the discharge power density J in order to achieve the maximum possible range The discharge power dw (=so‧J) is determined, and the flow rate qo of the raw material gas supplied to the discharge space with a discharge length d of tens to hundreds of μm is set to the largest possible range.

70mm至

140mm的範圍，俾規限放電面積so，而為了獲致原料氣體的總氣體流量Q提高的臭氧產生器，必須將一單位放電室多段層疊，俾確保臭氧產生器的總放電面積S(=2‧n‧so)。 As the discharge area of a subject in a particular method so 30cm ² to 160cm ^2, in one example, the Department of circular shape in plan view of the discharge chamber of the discharge surface diameter set at

70mm to

The range of 140mm limits the discharge area so, in order to obtain an ozone generator with an increased total gas flow rate Q of the raw material gas, a unit of discharge chamber must be stacked in multiple stages to ensure the total discharge area S(=2‧ n‧so).

Further, the discharge area of the discharge surface so a set of restrictions in the discharge chamber shape generator 30cm ² to 160cm ^2, the investment will be the total discharge power and discharge electric power density DW is the parameter J (= DW / S) When it is limited to a lower value, the total discharge area S of the ozone generator must be enlarged, and the number of stacked layers of a discharge chamber n (=S/(2‧so)) must be increased. When the number n of discharge surfaces is increased, in order to avoid an increase in the production cost of the ozone generator, it is preferable to set the discharge power density J that can be put into a set of discharge surfaces within the range of the most effective conditions in the ozone gas generation system 1000 Higher value.

To construct an ozone gas generating system 1000 in which the total gas flow rate Q of the raw material gas capable of taking out high-concentration ozone gas is increased to a larger gas flow rate, the discharge area so, the discharge power density J, the input discharge power dw, and supply to a discharge In terms of the raw material gas flow rate qo of the space, the realization of a unit discharge cell satisfying the above conditions and the increase in the number n of discharge cells stacked in multiple stages are indispensable.

In addition, in a region where the total gas flow rate Q of the raw material gas is large, in order to constitute the ozone gas generating system 1000 in which the high-output ozone extraction amount Yt is increased to the maximum, the discharge area so, the discharge power density J, and the input The discharge power dw and the flow rate qo of the raw material gas supplied to one discharge space are set to a maximum value within a possible range, and a set of discharge surfaces satisfying the above conditions are realized, and a plurality of stages are stacked on the number n of discharge cells.

In other words, in the ozone generator 200, there must be 2n sets of discharge surfaces that meet the above conditions, and can output ozone that meets the total discharge power DW (= 2‧n‧dw) of the ozone generation AC voltage With power supply 100.

As a result, the ozone gas generation system 1000 can supply the total gas flow rate Q (=α‧2‧n‧qo) of the raw material gas to be given to 2n discharge spaces. In addition, the α value is a constant indicating a reduction rate when a set of 2n discharge surfaces are stacked and ozone gas is merged.

Next, the conditions for the operation of the ozone generator for taking out high-concentration ozone gas will be explained.

Fig. 6 shows the generator A-shaped generator, B-shaped generator, and C-shaped generator when the total discharge power DW with respect to the operating frequency f of the ozone power supply 100 is applied. The characteristic curve of the load peak voltage Vp.

Hereinafter, the basis for setting the operating frequency of the ozone power supply 100 to 20 kHz to 50 kHz will be described with reference to FIG. 6.

In FIG. 6, the characteristic 7000a shows the characteristic of the load peak voltage Vp when the discharge power density J (=DW/S) of the generator of the A-type discharge cell shape is 2W/cm ² .

The characteristic 7000b shows the characteristic of the load peak voltage Vp when the discharge power density J of the generator of the B-type discharge cell shape is 4W/cm ² .

In addition, the characteristic 7000c represents the characteristic of the load peak voltage Vp of the C-type generator when the discharge power density J is 8 W/cm ² .

In the characteristic 7000b of the peak load voltage Vp when the discharge power density J is 4 W/cm ² , it has been experimentally determined that the highest concentration of ozone gas can be taken out in the region 99a in the generator of the B-type discharge cell shape.

The characteristic 7000s1 and the characteristic 7000s1 indicated by dotted lines are characteristic diagrams for exploring the upper and lower limits of the discharge cell shape boundary value of the discharge power density J within the scope of the present invention.

The characteristic 7000s1 represents the boundary characteristic of the shape of the discharge cell in which the discharge power density J is at least 2.5 W/cm ² . The characteristic 7000s2 is the boundary characteristic of the shape of the discharge cell where the discharge power density J is set at a maximum limit of 6 W/cm ² .

Therefore, in order to obtain a high-concentration ozone gas of 400 g/m ³ or more at a predetermined gas flow rate Q from the relationship between the region 99a and the characteristics 7000s1 and 7000s2, and the gas flow rate Q that can be supplied obtains the desired amount of extracted ozone Yt The device discharge power density J (=DW/S), and the lower limit of the discharge power density J is set to about 2.5W/cm ² or more, and the upper limit of the discharge power density J is set in the condition range of about 6.0W/cm ² Ideal result.

Hereinafter, a power supply method in which the operating frequency f of the ozone power supply 100 is 20 kHz to 50 kHz will be described. Next, a description will be given regarding the use of the high-frequency inverter unit in the ozone power supply 100 In the case of the inverter circuit section 22, and in the case where the parallel resonance type is realized between the transformer 25 for parallel resonance belonging to the high-frequency and high-voltage transformer and the ozone generator 200.

As shown in Fig. 6, when the operating frequency f is lowered, if a larger total discharge power DW is input and the discharge power density J (=DW/S) is increased, the peak load voltage Vp shows an increased characteristic.

When the peak load voltage Vp is increased, in order to sufficiently ensure the withstand voltage of the ozone generator 200, the ozone generator 200 must be increased. As the power supply 100 for ozone, if the peak load voltage Vp does not reach 10 kVp, the inverter circuit section 22 can be simplified and stable.

In addition, if the load peak voltage Vp is 7 kVp or more, in order to ensure the withstand voltage, there will be a need to increase the parallel resonance transformer 25, or to increase the space distance between the high-pressure part and the low-pressure part of the ozone generator, the ozone generator itself Will be large.

Furthermore, there is also a problem that the turns ratio of the transformer 25 for parallel resonance becomes large. Therefore, as the ozone gas generating system 1000, it is preferable that Vp belonging to the load peak of the load applied voltage Vd is set to less than 7 kVp (5.0 kVrms) to supply the desired total discharge power DW.

As shown in Fig. 6, when the load peak voltage Vp is set to less than 7 kVp (5.0 kVrms) in the case of the ozone power supply 100, high-concentration ozone gas of 400 g/m ³ or more can be taken out, and the total gas The flow rate Q sets the extracted ozone amount Yt to the maximum ozone gas generation system 1000, and the operating frequency f is preferably 20 kHz or more.

On the other hand, when the operating frequency f increases, the ozone generating capacity generated by the ozone generator 200 tends to decrease. Therefore, as a high-concentration ozone gas generating device that can take out high-concentration ozone of 400 g/m ³ or more, the operating frequency f It is preferably less than 50 kHz.

In addition, a high-concentration ozone gas of 400 g/m ³ or more is taken out at a gas flow rate of the total gas flow rate Q (raw gas flow rate) of about 3.0 L/min or more, and the ozone amount is taken out at the total gas flow rate Q The ozone gas generating system 1000 required for Yt to reach the maximum must have an ozone power supply 100 that supplies a total discharge power DW of 1.8 kW or more. Therefore, as the transformer 25 for parallel resonance that can output 1.8 kW or more, considering the noise countermeasure surface of the ozone power supply or the stable supply surface of the output power, it is practically preferable that the operating frequency f is not more than 20 kHz to 30 kHz.

As described above, as shown in FIG. 6, as the gas flow rate of the total gas flow rate Q (source gas flow rate) of the raw material gas in the gas flow rate range of about 3.0 L/min or more, the ozone gas of 400 g/m ³ or more high concentration ozone is taken out To produce system 1000, the following conditions must be met.

‧A discharge area so of a unit discharge cell is set at about 30cm ² to about 160cm ² .

‧The discharge power dw (=so‧J) of a unit discharge space is regulated from a discharge area so and a discharge power density J.

In addition, as a configuration condition of the ozone gas generation system 1000 that sets the total gas flow rate Q of the raw material gas to the maximum possible range so as to obtain a high output ozone extraction amount Yt, it is preferable to satisfy the following conditions.

‧The discharge power density J (=DW/S) is limited to the setting range of 2.5W/cm ² to 6W/cm ² .

‧The flow rate qo of the raw material gas supplied to a discharge space with a discharge gap length d of tens to hundreds of μm is limited to a weak range of about 0.5 L/min to about 2.5 L/min.

By setting the raw material gas flow rate qo and a discharge area so as to satisfy the above conditions, the average gas flow rate vo/d of a discharge space can be set at the optimal speed, and the gas residence time To in the discharge space can be shortened, so that Remove high concentration ozone gas.

Furthermore, it is preferable to configure the ozone generator in the following manner.

‧An ozone generator with a high concentration of ozone taken out by a set of discharge surfaces, and a multi-stage stack of discharge chambers with basic chambers S1 and S2.

Furthermore, the power supply 100 for ozone preferably satisfies the following conditions.

‧The output frequency of the AC voltage for ozone generation is set in the range of 20kHz to less than 50kHz, so that the desired total discharge power DW can be output and controlled.

By configuring the ozone gas generation system 1000 by satisfying the above conditions, the effect of taking out a large flow rate and high concentration of ozone gas can be achieved, and the ozone gas generation system 1000 can be constructed in a simplified and inexpensive manner.

(Various conditions of ozone gas generation system 1000)

The ozone gas generating system 1000 is a multi-stage stacking of discharge chambers with a large flow rate of the raw gas total gas flow rate Q (raw gas flow rate) gas flow range of about 3.0 L/min or more, so that the ozone concentration taken out reaches a high concentration (400 g/ m ³ ).

In order to take out ozone gas of high concentration of 400 g/m ³ or more, the ozone gas generating system 1000 is preferably provided with an ozone power supply 100 and a ozone power supply whose specific power value DW/Q is set to 600 or more.

In particular, the total discharge power DW provided by the ozone generating AC voltage supplied by the ozone power supply 100 is preferably about 1.8 kW to 15 kW.

If the power supply 100 for ozone increases the discharge gap length d of the discharge space, the gas residence time To will become very long, and the amount of ozone decomposition relative to the amount of ozone generated in the discharge space will become very large, making it impossible to take out high concentration Ozone gas.

In addition, when the discharge gap length d is too short, and the flow velocity of the gas passing through the discharge space increases, the ozone gas generated due to the proximity of the discharge surface collides with the wall of the discharge surface, or the gas collision in the discharge space or the generated electrons, ions 3. The collision of discharge gas increases, which makes the amount of ozone decomposition become very large. In this way, if the discharge gap length d is too short, the high-concentration ozone gas cannot be taken out. Therefore, the discharge gap length d is preferably set within a short gap length range of tens to hundreds of μm. In particular, in order to take out a higher concentration of ozone gas, by setting the discharge gap length d in the range of 20 μm to 100 μm, a better effect can be achieved.

As the range of the total gas flow rate Q of the raw material gas, it can obtain 400 g/m ³ or more of high-concentration ozone gas in the range of 3SLM to 25SLM, and, compared with the conventional device, the range of high-concentration ozone gas can be obtained It is preferably in the range of about 3SLM to 50SLM.

(Effect of this embodiment)

The configuration of the power supply 100 for ozone of this embodiment includes: an ozone generator 200, and a basic chamber S1 (S2) having a pair of flat plate electrodes 1 and high-voltage electrodes 3a (3b) respectively arranged as discharge surfaces via a dielectric; And the power supply 100 for ozone is applied to the ozone generator 200 with an alternating voltage for ozone generation.

Oxygen-containing raw material gas is supplied to the ozone generator 200, so that the ozone generator 200 generates dielectric barrier discharge in the discharge space formed by the discharge surface of the basic chamber S1 (S2), and ozone gas is generated from the raw material gas supplied to the discharge space And output the ozone gas to the outside.

The ozone generator 200 includes a plurality of discharge cells (S1, S2) stacked in multiple stages. Moreover, the ozone generator 200 whose output ozone has been highly concentrated satisfies the following condition (1) and condition (2).

(1) a plurality of discharge cells, so the discharge area of each discharge surface is formed by lines is set in 30cm ² to 160cm ² (30cm ² or more less than 160cm ²⁾ range.

(2) The raw material gas flow rate qo of the raw material gas supplied to the discharge spaces formed by the various discharge surfaces in the multiple discharge chambers is set at 0.5L/min to 2.5L/min (0.5L/min or more does not reach 2.5L/min ).

Furthermore, the gas flow rate Q and discharge power DW supplied to the ozone generator 200 are set to the maximum possible range, and in order to obtain a higher extracted ozone amount Yt, in addition to the above condition (1) and condition (2) The ozone generator 200 must still meet the following condition (3).

(3) The discharge power density J input to the discharge space of each of the plurality of discharge cells is set in the range of 2.5W/cm ² to 6W/cm ² (2.5W/cm ² or more but less than 6W/cm ² ).

The ozone gas generation system 1000 of the present embodiment achieves the following effects on each discharge surface of a plurality of discharge cells by satisfying the above conditions (1) to (3). In addition, when the three conditions are satisfied, the discharge gap length d of the ozone generator must be set to a short gap of tens to hundreds of μmn. Hereinafter, this point will be described in detail.

Dielectric barrier discharges with a short gap length of tens to hundreds of μm can achieve high electric field discharge. That is, the short gap dielectric barrier discharge is more capable of forming a discharge with high energy discharge light energy, which can effectively stimulate the gas containing the catalyst gas or the photocatalyst coated on the discharge surface. As a result, the oxygen dissociation is promoted. The effect is even more improved. Therefore, when the ozone gas generating system and the ozone gas generating method satisfying the conditions (1) to (3) are realized, the discharge gap length of the ozone generator is preferably set to tens to hundreds of μm.

The ozone gas generating system 1000 can shorten the gas residence time To of the discharge space (formed by a pair of discharge surfaces) of each discharge cell by satisfying the above conditions (1) and (2) to suppress the total ozone decomposition amount Yd.

As a result, the ozone gas generating system 1000 can satisfy the above conditions (1) and (2), and by setting the flow rate qo of the raw material gas supplied to the discharge surface of each discharge cell and the discharge power dw to the possible range Maximum, so that the amount of ozone to be taken out yt is maximized, and the conditions for taking out high-concentration ozone gas are obtained.

The ozone gas generation system 1000 further satisfies the condition (3), so that the amount of ozone generated from each discharge cell can be ensured to be more than a predetermined amount, and can be extracted with excellent efficiency, so that the amount of ozone extracted Yt can be further increased.

As a result, the ozone gas generation system 1000 can achieve the effect of suppressing the system configuration to the minimum necessary limit, and efficiently increasing the high-concentration ozone or taking out the amount of ozone Yt and outputting it to the outside.

In this way, the ozone gas generation system 1000 can satisfy the conditions (1) to (3) by further satisfying the above condition (3) in addition to the condition (1) and the condition (2), and can The flow rate qo of the raw material gas and the discharge power dw supplied to the discharge space of each discharge cell are set to the maximum possible range, and the amount of taken out ozone yt is increased to the maximum.

As a result, the ozone gas generation system 1000 of the present embodiment can suppress the system configuration to the minimum necessary level, and achieve the effect of outputting high-concentration ozone gas or high-generation ozone gas to the outside.

Furthermore, the ozone generator 200 of the ozone gas generating system 1000 of this embodiment further satisfies the following condition (4).

(4) The cooling temperature of the ozone generator 200 provided by the cooling mechanism is above 5°C.

By further satisfying the above condition (4), the ozone generator 200 of the ozone gas generating system 1000 of the present embodiment eliminates the necessity of extremely reducing the cooling temperature of the ozone generator 200 provided by the cooling mechanism, and can seek a cooling mechanism Simplification. In addition, the upper limit of the above restriction conditions is preset to about 30°C with respect to normal temperature (20°C). In addition, in a case where a higher cooling effect is emphasized, it is preferable to set the cooling temperature to 0°C or more of the water condensation temperature.

Furthermore, the ozone generator 200 of the ozone gas generating system 1000 of this embodiment further satisfies the following condition (5) and condition (6).

(5) The total gas flow rate Q of the entire plurality of discharge cells supplied into the ozone generator 200 is 3.0 L/min or more.

(6) The specific power value DW/Q of the ratio of the total discharge power DW to the total gas flow rate Q given to the entire plurality of discharge cells in the ozone generator 200 is 600 (W.min/L) or more.

In addition, the condition (5) is for the purpose of taking out a high concentration of ozone gas, and the condition (6) can achieve the effect of increasing the amount of ozone gas output to the maximum limit, which is a side effect of achieving the purpose of the condition (5).

The ozone power supply 100 and the ozone generator 200 of the ozone gas generation system 1000 achieve the following effects by further satisfying the above condition (5) and condition (6).

By satisfying the above condition (5), the ozone gas generating system 1000 ensures a sufficiently large total gas flow rate Q to supply raw gas to a plurality of discharge cells that can take out high-concentration ozone of, for example, 400 g/m ³ or more, and finally High concentration ozone gas can be obtained, and the amount of ozone taken out Yt can be increased.

The ozone gas generation system 1000 satisfies the above condition (6), and in addition to the effect of the condition (5), in the environment satisfying the condition (1) to the condition (6), for example, the following effects are achieved. By setting the total gas flow rate Q and the total discharge power DW supplied to the ozone generator 200 to the maximum possible range, it is possible to increase the extracted ozone amount Yt to the maximum.

As a result, the ozone gas generating system 1000 of the present embodiment can achieve the effect of suppressing the system configuration to the minimum necessary level, and can output a larger capacity and high concentration of ozone gas to the outside.

Moreover, the discharge surfaces of the basic chambers S1 and S2 constituting the discharge chamber in the ozone generator 200 are respectively circular in plan view, and the ozone generator 200 further satisfies the following condition (7).

(7) The outer diameter of each discharge surface in the plurality of discharge cells is set in the range of 70 mm to 140 mm (70 mm or more but less than 140 mm).

In addition, if the discharge chambers (combination of the basic chambers S1 and S2) having the above discharge surfaces are arranged on n same planes in the ozone generator to constitute a variation of the ozone gas generation system 1000 with an increased number of discharge chambers, The basic structure shown in Fig. 1 has the same effect.

The ozone gas generation system 1000 makes it easier to realize the discharge area so that satisfies the condition (1) by satisfying the above condition (7), and it is easier to set the average gas flow rate vo/d flowing into the gas into the average cross-section sav at Appropriate value.

In addition, the ozone power supply 100 of the ozone gas generating system 1000 sets the output frequency f (operation frequency f) in the range of 20 kHz to 50 kHz (20 kHz or more but less than 50 kHz), so as to output the AC voltage for ozone generation to Ozone generator 200. The output frequency f (operation frequency f) of the more practical ozone power supply 100 is preferably in the range of 20 kHz to 30 kHz (20 kHz or more and less than 30 kHz).

Therefore, the ozone gas generation system 1000 sets the peak voltage value of the ozone generation alternating voltage applied to the plurality of discharge cells in the ozone generator 200 to 7 kVp or less, and can realize the discharge power DW desired by the ozone generator 200.

In addition, the parallel resonance transformer 25 of the ozone power supply 100 has an internal magnetizing inductance value Lt, and a plurality of discharge cells in the ozone generator 200 has an overall capacitance value C0.

In addition, the power supply 100 for ozone sets the output frequency f near the parallel resonance frequency fc that satisfies the above equation (4).

The ozone gas generating system 1000 sets the output frequency f to be near the parallel resonance frequency fc, and performs parallel resonance when the total discharge power DW is input to the ozone generator 200 to make the inverter unit (inverter circuit unit 22) The output power can be increased.

That is, by performing parallel resonance when the total discharge power DW is input between the parallel resonance transformer 25 and the ozone generator 200, the output power of the inverter circuit section 22 can be increased.

As a result, the ozone power supply 100 can supply the ozone generating AC voltage satisfying the desired total discharge power DW to the ozone generator belonging to the load side.

In addition, the desired total discharge power DW may be a total discharge power DW of 1.8 kW or more. Thus, discharge power density can be put into each discharge chamber in the ozone generator 200 J (= DW / S) can be set in the range of 2.5W / cm ² to 6W / cm ² in.

As a result, the ozone gas generating system 1000 can realize the high-efficiency ozone power supply 100 even if the total gas flow rate Q and the total discharge power DW supplied are set to the maximum possible value in order to extract ozone gas with a high concentration. Achieve the effect of achieving a simplified ozone gas generation system.

<Extended method invention>

In this embodiment, the ozone gas generating system 1000 as the device invention will be described. However, it can also be extended to use the ozone gas generating method of the above-mentioned ozone power supply 100 and ozone generator 200 as a modified example of the present invention.

That is, an ozone generator 200 having: a discharge chamber arranged in a pair of plate electrodes 1, 3 (3a, 3b) via a dielectric (2a, 2b) can be used, and the ozone generator 200 can be provided for ozone generation The alternating-current power supply 100 for ozone is developed as an ozone gas generating method that generates high-concentration ozone gas.

The ozone gas generation method pertaining to a modified example of the present embodiment executes the following steps (1) and step (2) corresponding to the conditions (1) and (2) of the ozone gas generation system 1000 described above.

(1) The discharge area of the discharge surface so each of the plurality of discharge cells are set in a step range of less than about 30cm ² or more of the 160cm ^2.

(2) The step of setting the raw material gas flow rate qo of the raw material gas supplied to the discharge space formed by the discharge surface formed by one of the plurality of discharge cells to a discharge surface of 0.5 L/min or more and not exceeding 2.5 L/min.

Furthermore, in order to input the gas flow rate Q and the total discharge power DW supplied to the ozone generator 200 to the maximum limit within the possible range, to obtain the maximum extracted ozone amount Yt, except In addition to the above step (1) and step (2), the ozone gas generating method preferably performs the following step (3).

(3) will be the plurality of discharge cells by a discharge space of each discharge power density of the input J of the set range at step 2.5W / cm ² to 6W / cm ² of.

The above ozone gas generation method can shorten the gas residence time To in the discharge space of each discharge cell by performing the steps (1) and (2), so as to suppress the decomposition amount of ozone gas.

Therefore, as long as the above-mentioned ozone gas generating method executes steps (1) and (2), the flow rate qo of the raw material gas supplied to the discharge space of each discharge cell and the discharge power dw can be set to the maximum possible range. To achieve the effect of removing ozone gas at a high concentration.

If the above ozone gas generation method further performs step (3), the gas flow rate q and the discharge power dw supplied to the discharge surface of each discharge cell are set to the maximum possible range, the amount of ozone taken out yt can be increased To the maximum effect.

As a result, the ozone gas generation method belonging to a modified example of the invention of the present invention can achieve the effect of outputting high-concentration ozone or high-generation ozone gas to the outside.

Furthermore, the above-mentioned ozone gas generation method may perform the steps for satisfying the conditions (4) to (7) in accordance with the above conditions (4) to (7) of the ozone gas generation system 1000, and achieve ozone gas generation System 1000 has the same effect.

<other>

In the present embodiment, it is disclosed that the shape of the discharge surface of the discharge cell is the ozone generator 200 having a circular shape in plan view, but a square or rectangular flat cell may be used to configure the shape of the discharge cell. In this case, it is only necessary to set the discharge power density J range that can satisfy the condition (2), and to stack a plurality of discharge cells.

Furthermore, as the discharge chamber, the coaxial cylindrical electrode tube may be made into a short tube, set in the range of the discharge power density J that satisfies the condition (3), and is composed of one type of multi-branch arrangement.

In this embodiment, the configuration of the internal magnetizing inductance value Lt of the parallel resonance transformer 25 having the high-frequency and high-voltage transformer belonging to the ozone power supply 100 is disclosed. In addition to this configuration, a parallel resonance resonance reactor may be added to the output portion of the parallel resonance transformer 25 to configure an ozone power supply.

In addition, as the ozone generator 200, it is disclosed that oxygen is supplied as a raw material gas, and a photocatalyst is coated on the discharge surface of the discharge chamber. However, it is not limited to this, and the ozone generator which supplies nitrogen-containing oxygen gas as a raw material gas may be used instead of the ozone generator 200.

Although the present invention has been described in detail, the above description is illustrative in all aspects, and the present invention should not be limited to this. Numerous variations that are not exemplified should be interpreted as being derived from the scope of the present invention without departing from the scope of the present invention.

1‧‧‧Earth cooling electrode

9‧‧‧Manifold box block

13‧‧‧ spacer

15‧‧‧Opening

17‧‧‧Output path

91‧‧‧ Cooling water output path

92‧‧‧Ozone gas output path

93‧‧‧ Cooling water input path

G _IN ‧‧‧ Raw gas

G _OUT ‧‧‧ output ozone gas

Claims (9)

An ozone gas generating system includes: an ozone generator (200) having a discharge chamber disposed on a pair of flat electrodes (1, 3) through a dielectric; and a power supply (100) for ozone, which is given to the ozone generator Generates an alternating voltage for ozone and supplies oxygen-containing raw material gas to the ozone generator. The ozone generator generates dielectric barrier discharge in the discharge space of the discharge chamber, and generates ozone gas from the raw material gas supplied to the discharge space And output the ozone gas to the outside, the discharge chamber includes a plurality of discharge chambers stacked in multiple stages, the ozone generator meets the following conditions (1) and (2), (1) in the plurality of discharge chambers, so the discharge area of each discharge surface is set based 30cm ² or more in a range less than 160cm ^2; (2) supplied to the raw material gas flow rate qo discharge line by each of the plurality of the gas discharge chamber space set at 0.5L / min The above does not reach the range of 2.5L/min. The ozone gas generating system as described in item 1 of the patent application scope, wherein the ozone generator further satisfies the following conditions (3), (3) the discharge power density J of the discharge space of each of the plurality of discharge cells is set at Above 2.5W/cm ^{2 does} not reach the range of 6W/cm ² . The ozone gas generating system as described in item 2 of the patent application scope, wherein the ozone generator further includes a cooling mechanism that cools the plurality of discharge chambers to a predetermined cooling temperature; the ozone generator further satisfies the following conditions (4 ), (4) The aforementioned predetermined cooling temperature is set at 5°C or higher. The ozone gas generation system as described in item 3 of the patent application scope, wherein the ozone power supply and the ozone generator are further provided to satisfy the following conditions (5) and conditions (6), (5) to the plurality of discharges The total gas flow rate Q of the entire chamber is 3.0 L/min or more; (6) The specific power value DW/Q of the ratio of the total discharge power DW given to the entire plurality of discharge chambers to the total gas flow rate Q is 600 (W -min/L), the total discharge power DW is regulated by the AC voltage for ozone generation. The ozone gas generating system as described in item 4 of the patent application scope, wherein the discharge surface of each of the plurality of discharge cells is circular in plan view; the ozone generator further satisfies the following conditions (7), (7) The diameter of the discharge surface of each of the plurality of discharge cells is set in a range of 70 mm or more but not 140 mm. The ozone gas generating system according to any one of the items 1 to 5 of the patent application scope, wherein the ozone power supply includes an inverter section (22), and the output frequency f is set to a range of 20 kHz or more but less than 50 kHz And output a high-frequency AC voltage; and a step-up transformer (25) to boost the high-frequency AC voltage to a high voltage to obtain the ozone generating AC voltage. An ozone gas generating system as described in item 6 of the patent application range, wherein the step-up transformer has an internal magnetizing inductance value Lt, the plurality of discharge cells have an overall capacitance value C0, and the output frequency f is set at Near the parallel resonance frequency fc that satisfies the following conditional expression, the conditional expression: fc=1/(2π‧(Lt‧C0) ^0.5 ). An ozone gas generation method is used: an ozone generator (200) having a discharge chamber disposed on a pair of plate electrodes (1, 3) through a dielectric; and an ozone power supply (100) to the ozone generator An alternating voltage for ozone generation is applied to generate ozone gas; an oxygen-containing raw material gas is supplied to the ozone generator, and the ozone generator generates a dielectric barrier discharge in the discharge space of the discharge chamber and supplies it to the discharge space The raw material gas generates ozone gas and outputs the ozone gas to the outside. The discharge cell includes a plurality of discharge cells stacked in multiple stages. The ozone gas generation method includes: (1) The discharge surface of each of the plurality of discharge cells so the discharge area of 30cm ² or more is set in step ² of less than 160cm range; and (2) supplied to the raw material gas flow rate of the material gas by the discharge space of each of the plurality of discharge cells is not set qo 0.5L / min or more Steps up to 2.5L/min. The ozone gas generating method as described in item 8 of the patent application scope, wherein the ozone gas generating method further includes the following steps (3), (3) the discharge power density J of the discharge space of each of the plurality of discharge cells set at 2.5W / cm ² or more step ranges 6W / cm ² of less than.

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