JP2007176723A - Discharge cell for ozone generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase the concentration of ozone without depending on the reduced amount of a discharge gap in the discharge cell for an ozone generator. <P>SOLUTION: The dielectric materials 10A and 10B are arranged between a high voltage electrode 15A and a low voltage electrode 15B, and a discharge gap 70 is formed between both dielectric materials 10A and 10B. The opposed faces of the dielectric materials 10A and 10B facing the discharge gap 70 are smoothed to ≤2 μm of surface roughness Ra. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a discharge cell used in an ozone generator.

  The discharge cells used in the ozone generator are roughly classified into a plate type and a tube type, and the plate type is further subdivided into a disc type and a square plate type. Plate-type discharge cells are often used to generate high-concentration ozone because the discharge gap formed between a pair of plate-shaped dielectrics can be easily narrowed, and the discharge gap dimensions can be easily equalized in the plane. Has been. A typical structure of the plate discharge cell will be described below.

  A plate-like dielectric made of a square ceramic plate or the like is disposed opposite to each other with a predetermined gap. The pair of dielectrics have electrode layers coated on the respective surfaces on the back side, thereby forming discharge gaps between the dielectrics. One of the pair of electrode layers is a high voltage electrode and the other is a low voltage electrode. By applying a predetermined high frequency high voltage between them, a discharge is generated in the discharge gap between the dielectrics, and the raw material passes therethrough Ozonize the gas.

  In general, the discharge gap is forcibly cooled from both sides, that is, the back sides of both electrodes, in order to increase the ozone generation efficiency. For this double-sided cooling, a refrigerant flow path is formed on each back side of the high voltage electrode and the low voltage electrode via an insulating plate. Usually, a plate-type discharge cell having such a double-sided cooling structure is used as a unit cell, and a plurality of the cells are stacked in the plate material stacking direction. One of such discharge cells is a discharge cell having a ceramic block structure described in Patent Document 1.

JP-A-11-268902

  Design factors in such a plate-type discharge cell include the thickness of a pair of dielectrics disposed between the high-voltage electrode and the low-voltage electrode, the gap amount of the discharge gap formed between the pair of dielectrics, the high-voltage electrode And the thicknesses of the high-voltage insulating plate and the low-voltage insulating plate arranged on the back side of the low-voltage electrode.

  The purpose of the dielectric is to increase the dielectric constant between the electrodes in order to generate silent discharge between the electrodes. In order to reduce the discharge voltage by reducing the distance between the electrodes, it is better that the thickness of the dielectric is thin. It is said that. However, if the dielectric is made too thin, the flatness is lowered, and the current state is selected to be about 0.1 to 2 mm. As a material of the dielectric, a high-purity alumina powder sintered body having a high mechanical strength and a high dielectric constant is used when cleanliness is required.

  The dielectric is also typically provided in contact with both the high and low voltage electrodes to avoid contact of the source gas and ozone gas with the electrodes. That is, both electrodes are covered with a dielectric, and a discharge gap is formed between the two dielectrics. However, when the cleanliness of ozone gas is not required, it may be provided only on one electrode side (usually the high voltage electrode side).

Regarding the gap amount of the discharge gap, it is said that the smaller is better for improving the ozone generation efficiency by cooling. From this point of view, the current state is reduced to 0.4 mm or less, and 0.1 mm (100 μm) or less is also realized. Has been. However, if the gap amount is too small, the flatness of the surface of the dielectric (the surface in contact with the discharge gap) will have a significant effect on the in-plane uniformity of the gap amount, and the ozone concentration will decrease. Cause. Due to such secondary problems, the current ozone concentration is limited to about 300 g / m ³ (N).

  An object of the present invention is to provide a discharge cell for an ozone generator that can increase the ozone concentration without depending on the reduction of the gap amount in the discharge gap, and can effectively increase the ozone concentration as the gap amount is smaller. It is to provide.

  The present inventor has tried various approaches to increase the ozone concentration in the discharge type ozone generator. In addition to forming a very small gap with high in-plane uniformity, the high pressure side insulating plate is thinned and cooled. We are studying earnestly for the realization of various countermeasures such as ideas to enhance the ability. As one result of such research and development, the present inventor has found that the surface roughness of the dielectric material has a great influence on the ozone concentration, particularly the ozone concentration under a minimum gap.

  In general, silent discharge in the discharge gap required for ozone generation occurs at any time in the discharge gap as a perpendicular discharge column, and discharge in a small area near the surface of the dielectric contributes to ozone generation. Has been. The generated discharge column is preferably thick and stable.

  On the other hand, the use of a ceramic powder sintered body such as a high-purity alumina powder sintered body is increasing because the use of a clean gas as a dielectric material is increasing. For example, in the case of a high-purity alumina powder sintered body, alumina powder particles are exposed on the surface of the sintered body, but the alumina powder is very fine, and the surface of the sintered body looks smooth to the naked eye. As small as several μm. However, from a microscopic perspective, it cannot be said to be smooth.

  When the surface of the dielectric is rough, a thin and unstable discharge column is likely to be generated by the tip of the convex portion as a trigger. Still, when the gap amount of the discharge gap is large, the discharge column is shaped in the large gap, and the ozone generation efficiency is not so much affected. However, if the gap amount of the discharge gap is reduced, it becomes impossible to expect the shape of the discharge column in the discharge gap, and the roughness of the surface of the dielectric directly affects the deterioration of the shape of the discharge column and the resulting decrease in ozone generation efficiency. Will affect.

  The present inventor has shown that the fact that the ozone concentration increases as the surface of the dielectric becomes smoother from many experimental data using the discharge cell for the ozone generator, and the tendency thereof becomes more prominent as the gap amount in the discharge gap becomes smaller. It is confirmed and the reason is estimated as described above.

  The discharge cell for an ozone generator of the present invention has been completed on the basis of such knowledge, and at least one electrode is formed to form a discharge gap between a high voltage electrode and a low voltage electrode to which a predetermined alternating voltage is applied. In the discharge cell in which a dielectric is disposed in contact with each other, the roughness of the surface of the dielectric that contacts the discharge gap is 2 μm or less in terms of Ra.

  By mirror-treating the surface in contact with the discharge gap of the dielectric to 2 μm or less with Ra, the ozone concentration of the generated ozone gas increases despite the other cell specifications and operating conditions being the same. As the Ra roughness is smaller (smooth), the ozone concentration tends to be higher. Therefore, Ra is preferably 1 μm or less, and particularly preferably 0.1 μm or less. The lower limit is not particularly defined, but the mirror polishing processing technique for smoothing the surface of the dielectric has technical and cost restrictions, and is limited by this aspect.

  The relationship between the surface roughness of the dielectric and the ozone concentration, more specifically, the tendency of the ozone concentration to increase with the smoothing of the surface becomes more prominent as the gap amount in the discharge gap becomes smaller. That is, the smoothing of the dielectric surface is more effective for discharge gaps with smaller gaps. From this viewpoint, the gap amount in the discharge gap is preferably as small as possible, specifically 50 μm or less, and particularly preferably 35 μm or less. Reduction of the gap amount is effective for increasing the concentration from the viewpoint of cooling or the like. However, if the gap amount is reduced, a decrease in in-plane uniformity becomes a problem, and as described above, there is a limit from this aspect.

  When the dielectric is a ceramic sintered body, the ceramic is preferably alumina having a purity of 80% or more, particularly preferably alumina having a purity of 90% or more, particularly 95% or more. Alumina is suitable because it is inexpensive among ceramics and has chemical resistance and sputtering resistance. Moreover, high purity is preferable in order to increase the cleanliness of ozone gas. As ceramics other than alumina, sapphire, SiC, AlN or the like can be used, and as materials other than ceramics, quartz or the like can be used.

  The surface roughness of the dielectric varies depending on its material and structure. The ceramic sintered body and quartz melt described above have high performance as a dielectric for generating ozone and are widely used. However, the original surface roughness is relatively rough, and smoothing the surface is particularly effective. On the other hand, amorphous glass is also used as a dielectric for generating ozone, but this originally has a smooth surface, and the effect of smoothing the surface is small. From this viewpoint, the present invention is effective for dielectrics other than amorphous glass, and is particularly effective for dielectrics of ceramic sintered bodies and quartz melts.

  When impurities in the dielectric plate are reduced, a decrease in ozone concentration becomes a problem. In order to solve this problem, titanium oxide is preferably contained in at least a surface layer portion of the dielectric plate in contact with the discharge gap, and titanium oxide is contained in the alumina substrate in an amount of 0.006 to 6% by weight in terms of the amount of Ti element. A sintered body is particularly preferable from the viewpoints of ozone generation characteristics and cleanliness.

  As for the arrangement form of the dielectric, one dielectric may be arranged in contact with one electrode between the high voltage electrode and the low voltage electrode, or a pair of dielectrics may be arranged in contact with both electrodes. Good. In either case, it is necessary to manage the roughness of at least the surface of the dielectric that contacts the discharge gap. Regarding the roughness of the opposite surface, that is, the surface in contact with the electrode, it is desired to manage the roughness smoothly from the viewpoint of uniform dielectric constant.

  When a pair of dielectrics are arranged in contact with both the high-voltage electrode and the low-voltage electrode, management of the surface roughness of the dielectric can be relaxed compared to the case where the dielectric is arranged in contact with one electrode. That is, even if the surface roughness of both dielectrics is 3 μm or less in Ra, the same effect can be obtained as in the case of 2 μm or less in the case of one-sided arrangement. From this point of view, the surface roughness in the case of the two-sided arrangement is preferably 3 μm or less in terms of Ra, but needless to say, the smoother the surface, the 2 μm or less, 1 μm or less, and 0.1 μm or less.

  Examples of the mirror surface processing method for smoothing the surface of the dielectric include lapping processing using various slurries.

  The discharge cell for an ozone generator of the present invention has a surface roughness in contact with at least one electrode and a dielectric discharge gap disposed between the electrodes in order to form a discharge gap between the high voltage electrode and the low voltage electrode. By smoothing to 2 μm or less with Ra, the ozone concentration can be increased without depending on the reduction of the gap amount in the discharge gap. If combined with the reduction of the gap amount, the ozone concentration can be increased more effectively.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded perspective view of a discharge cell for an ozone generator showing an embodiment of the present invention, and FIG. 2 is a schematic sectional view of the discharge cell.

  As shown in FIGS. 1 and 2, the plate-type discharge cell for an ozone generator according to this embodiment has a configuration in which a plurality of square plate members are stacked in the plate thickness direction. The plurality of plate materials are all fired plates of high-purity alumina, and are joined via a glass-based joining layer 50. Positioning through holes are provided at the four corners of each plate member, and the corners are rounded.

  The two middle plates are dielectrics 10A and 10B. The thickness is, for example, 0.3 mm. The surfaces of the dielectrics 10A and 10B, particularly the opposing surfaces, are mirror-finished to a Ra of 2 μm or less by a mirror-finishing method such as lapping.

  On both side edge portions of each dielectric 10 in parallel, long-hole shaped through holes 11 along the side edges are provided. The through-holes 11 and 11 are for gas distribution, and are provided continuously and linearly in almost the whole area except for both ends of both side edges. On the other parallel side edges of each dielectric 10, that is, the side edges perpendicular to the through holes 11, 11, elongated through holes 12, 12 are provided along the side edges. The through-holes 12 and 12 are for refrigerant circulation, and are provided continuously and linearly in almost the whole area except for both ends of both side edges.

  In order to form a large number of parallel gas flow paths 13, 13 extending from one of the through holes 11, 11 to the other surface of the dielectrics 10 </ b> A, 10 </ b> B, the ceramics except for the gas flow paths 13, 13 are formed. Layers 14 and 14 are laminated. The gas flow paths 13 and 13 are combined to form a discharge gap 70 between the dielectrics 10 and 10.

  The ceramic layer 14 is obtained by printing a paste made of alumina powder and glass powder on a portion other than the gas flow path on the opposite surface, repeating this to a predetermined thickness, and firing at a temperature equal to or higher than the melting point of the glass powder. Is formed. Each thickness of the ceramic layers 14, 14, that is, a rib height for forming the gas flow path 13 is, for example, 35 μm.

  Electrode layers 15A and 15B are coated on the back surface of the dielectrics 10A and 10B. The electrode layer 15A is a high-voltage electrode, and 15B is a low-voltage electrode, both of which are, for example, a metal thin film having a thickness of 5 μm formed by printing and baking silver paste, and surrounded by the through holes 11, 11, 12, and 12. It is provided in a square area. Two adjacent corner portions of the electrode layer 15 protrude from the corner portion of the dielectric plate 10 to form circular terminal portions 16 and 16. The terminal portions 16 and 16 in one electrode layer 15A are provided at two adjacent corner portions of the dielectric plate 10A, and the terminal portions 16 and 16 in the other electrode layer 15B are terminal portions in the electrode layer 15A. 16 and 16 are provided at two adjacent corner portions of the dielectric 10B so as not to overlap with each other.

  The plate materials disposed outside the dielectrics 10A and 10B are the insulating plates 20A and 20B. One insulating plate 20A is a high-voltage insulating plate, and the other insulating plate 20B is a low-voltage insulating plate. The high-voltage insulating plate 20A is intended to insulate the inner high-voltage electrode 15A from the outer refrigerant, and the thickness thereof is conventional. It is thin, for example, 0.9 mm. The low-voltage insulating plate 20B is exclusively for the purpose of ensuring the mechanical strength, and the thickness thereof is, for example, 0.3 mm. That is, the thickness of the high voltage insulating plate 20A is 1.5 times the total thickness (0.6 mm) of the dielectrics 10A and 10B arranged between the electrode layers 15A and 15B.

  On both side edges of the insulating plates 20A and 20B, there are provided through holes 21 and 21 for gas circulation having long holes corresponding to the through holes 11 and 11, respectively. The other parallel side edges of the insulating plates 20A and 20B are provided with through-holes 22 and 22 for circulation of a long hole corresponding to the through-holes 12 and 12, respectively.

  The plate materials arranged outside the insulating plates 20A and 20B are the slit plates 30A and 30B for forming the refrigerant flow path. The thickness is 0.5 mm, for example. On the both side edges of each slit plate 30 are provided through holes 31 and 31 for gas circulation having a long hole shape corresponding to the through holes 11, 11, 21 and 21. A large number of slits 33, 33,... Are provided in parallel between the through holes 31, 31 in order to form a refrigerant flow path. Both ends of the slits 33, 33... Reach the other parallel side edges of each slit plate 30 so as to overlap with the through holes 22, 22 for circulating the refrigerant.

  The plate members disposed further outside the slit plates 30A and 30B are the cover plates 40A and 40B. The thickness of one cover plate 40A is, for example, 4 to 5 mm, and the thickness of the other cover plate 40B is, for example, 2 mm. One cover plate 40A is provided with a gas supply hole 41a and a gas discharge hole 41b communicating with the through holes 31, 31 of the inner slit plate 30A, respectively. A pair of recesses is provided on the back surface of the cover plate 40A so as to correspond to both end portions of the slits 33, 33,..., That is, the through holes 12, 12, 22, and 22. The lid plate 40A is provided with a refrigerant supply hole 42a and a refrigerant discharge hole 42b that communicate with a pair of recesses on the back surface side.

  These plate materials (sintered plates of high-purity alumina) are joined as follows.

  A glass-based bonding paste is applied to the bonding surface of each plate material to a thickness of about 30 μm, for example. The bonding paste is prepared by kneading glass powder with a binder to have a predetermined viscosity. When the application of the bonding paste is finished, the plate material is charged into a heating furnace, and the bonding paste is baked at a temperature of, for example, 850 ° C. or higher, which is the melting point of the glass powder. When the bonding paste is baked, the respective plate materials are overlapped, and the positioning pins 60 are pierced through the through holes at the four corners. The four positioning pins 60 also serve as rod-shaped leads, two of which are electrically connected to the terminal portions 16 and 16 of the high-voltage electrode layer 15A, and the remaining two are the two terminal portions 16 of the low-voltage electrode layer 15B. , 16 are conducted. Finally, the stacked plate materials are charged into a heating furnace, and the joining paste is fired at a temperature of, for example, 850 ° C. or higher, which is the melting point of the glass powder.

  By this firing, the dielectrics 10A and 10B, the outer insulating plates 20A and 20B, the outer slit plates 30A and 30B, and the outer lid plates 40A and 40B are bonded via the glass-based bonding layer 50. As a result, the discharge cell of this embodiment is completed. The characteristics of the completed discharge cell are as follows.

  By combining the gas flow paths 13 and 13 between the dielectrics 10A and 10B, a closed space for discharge, that is, a discharge gap 70 is formed between the dielectrics 10A and 10B. The thicknesses of the ceramic layers 14 and 14 forming the gas flow paths 13 and 13 are, for example, 35 μm, and the gap amount of the discharge gap 70 in this case is 70 μm. One of the ceramic layers 14 can be omitted, and the gap amount of the discharge gap 70 in this case is halved to 35 μm. The electrode layers 15A and 15B coated on the rear surface of the dielectric plates 10A and 10B are joined together with the terminal portions 16 and 16 between the dielectric plate 10 and the insulating plate 20 joined to the outside thereof. Encapsulated and insulated by layer 50.

  The terminal portions 16 and 16 of the high-voltage electrode layer 15A provided on the back side of the dielectric plate 10A are drawn out of the lid plate 40A by the two rod-shaped leads 60 and 60 and connected to the power source. On the other hand, the terminal portions 16 and 16 of the low-voltage electrode layer 15B provided on the back side of the dielectric plate 10B are drawn out to the outside of the lid plate 40A by another two rod-shaped leads 60 and 60 and grounded.

  The through holes 11, 11 of the dielectric 10, the through holes 21, 21 of the insulating plate 20, and the through holes 31, 31 of the slit plate 30 are continuous in the plate material stacking direction, so that they are vertically long and communicate with the discharge gap 70. Gas flow paths 80, 80 are formed in the laminate. Further, the through holes 12 and 12 of the dielectric 10 and the through holes 22 and 22 of the insulating plate 20 are continuous in the plate material laminating direction, so that the longitudinal direction communicates with both ends of the slits 33, 33. A horizontally long refrigerant flow path is formed in the laminate.

  In the operation of the discharge cell, a predetermined high-frequency high voltage is applied to the high-voltage electrode layer 15A via the two rod-shaped leads 60, 60. At the same time, a raw material gas is introduced into one of the two vertical gas flow paths 80, 80 formed in the stacking direction from the gas supply hole 41a of the cover plate 40A, and two vertical refrigerant flows formed in the stacking direction. Cooling water is introduced into one of the paths from the refrigerant supply hole 42a of the lid plate 40A.

  The source gas introduced into one of the gas flow paths 80, 80 travels from one end portion to the other end of the discharge gap 70 formed between the dielectrics 10 </ b> A, 10 </ b> B, and is ozonized during this time. , 80, and is discharged to the outside through the gas discharge holes 41b of the cover plate 40A. The cooling water introduced into one of the two refrigerant channels flows through the slits 33, 33,... Of the slit plates 30A, 30B in the longitudinal direction, passes through the other of the two refrigerant channels, and passes through the other of the two refrigerant channels. It is discharged from the discharge hole 42b. As a result, the discharge gap 70 formed between the dielectrics 10A and 10B between the electrode layers 15A and 15B is cooled via the insulating plates 20A and 20B from both sides.

  In the discharge cell of the present embodiment, the opposing surfaces of the dielectrics 10A and 10B are smoothed to 2 μm or less with Ra. As a result, the discharge column generated in the discharge gap 70 between the dielectrics 10A and 10B becomes thick and stable, and the ozone concentration of the generated ozone gas increases. This effect will be clarified with specific numerical values in a later example.

  In addition, in the discharge cell of the present embodiment, the raw material gas and the ozone gas pass from one of the vertical gas flow paths 80, 80 to one of the vertical gas flow paths 80, 80 through the discharge gap 70 between the dielectrics 10A, 10B. It reaches. Here, the vertical gas flow paths 80, 80 are formed in a laminate in which high-purity alumina plate materials are bonded together by the glass bonding layer 50, and neither the high-purity alumina plate material nor the glass bonding layer 50 contains a contamination source. It is an inorganic non-metallic material. Further, the discharge gap 70 is formed by the rib-structure ceramic layer 14 and the glass bonding layer 50 between the dielectrics 10 </ b> A and 10 </ b> B made of a high-purity alumina plate, and the ceramic layer 14 is as clean as the glass bonding layer 50. It is an inorganic non-metallic material. Further, the electrode layer 15 is sealed by a glass bonding layer 50 between the dielectric plate 20 and the insulating plate 20 on the back side thereof.

  For these reasons, the raw material gas and the ozone gas do not come into direct contact with the metal, but pass only through a clean distribution path formed of a clean inorganic non-metallic material that does not contain a contamination source. In other words, all gas contact parts are made of a clean material. Therefore, there is no danger of contamination of the raw material gas and ozone gas by the discharge cell, and ozone gas having a high cleanliness is generated.

  Next, the effect of the surface roughness of the dielectric material on the ozone concentration in the discharge cell of the present invention is quantitatively shown to clarify the effect of the present invention.

  In the discharge cell shown in FIGS. 1 and 2, the roughness of the opposing surfaces of the dielectrics 10A and 10B was variously changed. Lapping was used as a mirror surface processing method for smoothing the facing surface, and the roughness was adjusted by changing the processing time. When not processed, the surface roughness Ra is 6.3 μm.

The dielectrics 10A and 10B were TiO ₂ -added alumina, and each thickness was 0.3 mm. The gap amount in the discharge gap 70 was 70 μm, the thickness of the low voltage insulating plate 20B was 0.3 mm, the thickness of the high voltage insulating plate 20A was 0.8 mm, and the thicknesses of the slit plates 30A and 30B were 0.5 mm.

  The source gas was high purity oxygen gas (6N), the flow rate was 0.5 L / min (N), and the inlet pressure was 0.25 MPa. The amount of cooling water was 3 L / min, and the temperature was 20 ° C. The relationship between the discharge voltage and the ozone concentration shows that the ozone concentration increases as the discharge voltage is increased, and the ozone concentration tends to decrease after a certain discharge voltage reaches its peak. The ozone concentration is the maximum ozone concentration, and the discharge voltage at which the maximum ozone concentration is obtained is expressed as 100, where 100 is the discharge voltage at which the maximum ozone concentration is obtained when the opposing surfaces of the dielectrics 10A and 10B are not processed.

When the opposing surface of the dielectric was not processed and the roughness Ra was 6.3 μm, the ozone concentration was 285 g / m ³ (N). When the opposite surface of the dielectric was mirror-finished to 2 μm with Ra, the ozone concentration increased to 297 g / m ³ (N), and the discharge voltage at that time decreased to 95. When the opposite surface of the dielectric was mirror-finished to 1 μm with smoother Ra, the ozone concentration rose to a higher 304 g / m ³ (N), and the discharge voltage at that time dropped to a lower 90.

  The gap amount in the discharge gap 70 was set to 35 μm. Other cell specifications and ozone generation conditions are the same. The results are as follows.

When the opposing surface of the dielectric was not processed and the roughness Ra was 6.3 μm, the ozone concentration was 335 g / m ³ (N). When the opposite surface of the dielectric was mirror-finished with Ra to 2 μm, the ozone concentration increased to 351 g / m ³ (N), and the discharge voltage at that time decreased to 90. When the opposite surface of the dielectric was mirror-finished to 1 μm with smoother Ra, the ozone concentration rose to a higher 372 g / m ³ (N), and the discharge voltage at that time dropped to a lower 80.

  Although the ozone concentration increases due to the reduction of the gap amount, the influence of the smoothing of the dielectric surface on the increase of the ozone concentration is more remarkable than when the gap amount is 70 μm.

  The embodiment shown in FIGS. 1 and 2 is a square plate type discharge cell, but it may be a disc type discharge cell. In the embodiment, the dielectrics 10A and 10B are provided in contact with the electrode layers 15A and 15B between the high voltage electrode layer 15A and the low voltage electrode layer 15B, but one of them may be omitted. Further, if a sufficient cell strength can be obtained by design, the low-pressure insulating plate 20B can be omitted.

It is a disassembled perspective view of the discharge cell which shows one Embodiment of this invention. It is a schematic cross section of the same discharge cell.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Dielectric plate 11,12 Through-hole 13 Gas flow path 14 Ceramic layer 15 Electrode layer 16 Terminal part 20 Insulating plate 21,22 Through-hole 30 Slit plate 31 Through-hole 33 Slit 40 Lid plate 41 Gas hole 42 Refrigerant hole 50 Glass bonding layer 60 Rod-shaped lead 70 Discharge gap 80 Vertical gas flow path

Claims (4)

  A dielectric is disposed between the electrodes in contact with at least one of the electrodes so as to form a discharge gap between the high-voltage electrode and the low-voltage electrode to which a predetermined alternating voltage is applied, and the surface of the dielectric is in contact with the discharge gap. A discharge cell for an ozone generator having a roughness Ra of 2 μm or less.   The discharge cell for an ozone generator according to claim 1, wherein the dielectric is a ceramic sintered body or a quartz crystal.   The pair of dielectrics are disposed between the high-voltage electrode and the low-voltage electrode so as to be in contact with both electrodes, and the roughness of the surface in contact with the discharge gap of both dielectrics is 3 μm or less in Ra. Ozone generating cell.   The discharge cell for an ozone generator according to claim 1, wherein a gap amount in the discharge gap is 50 μm or less.

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