JP2011105577A - Method and apparatus for generating ozone by coaxial cylinder type catalytic electrode - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and apparatus for generating ozone by a coaxial cylinder type catalytic electrode which accelerates ozone generation by bringing oxygen gas activated by discharge into contact therewith. <P>SOLUTION: This method for generating ozone employs a cylindrical dielectric body 14 and a cylindrical electrode 15 disposed outside thereof, coaxially to the cylindrical dielectric body 14 and providing a gap S with a predetermined space to the peripheral surface of the cylindrical dielectric body 14; and generates ozone by feeding oxygen to the gap S and discharging the cylindrical electrode 15. On the surface of the cylindrical electrode 15 facing the peripheral surface of the cylindrical dielectric body 14, a plurality of protrusions 16 are formed and a catalytic metal is coated thereon. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ozone generation method and apparatus using a coaxial cylindrical catalyst electrode capable of increasing ozone generation efficiency.

  Water treatment ozone treatment is widely performed, and there is a growing demand for advanced treatment of sewage treated water. In ozone treatment, ozone is an energy-intensive raw material, and requires 13 kWh of electricity to produce 1 kg of ozone. This high manufacturing cost hinders the spread of ozone treatment. As for the principle of ozone generation, most of them are electric discharge in air or oxygen gas and those using an ultraviolet lamp, and it is a system using electric discharge that can achieve large scale and low cost. In the electrical discharge method, various control methods for discharge and electrodes used for discharge have been devised, and a number of ozone generators have been manufactured.

  For example, coaxial cylindrical electrodes are used in small to large ozone generators, and are used in waterworks and sewage treatment plants. In addition, as an ozone generator that has a coaxial cylindrical electrode and generates ozone from oxygen or air, a cylindrical high-voltage electrode is inserted into a tube-shaped ground electrode (made of stainless steel), and the ground electrode is warped. An apparatus that is adapted to bend and improve ozone generation efficiency is known (see Patent Document 1).

  In addition, the present inventors previously proposed Non-Patent Document 1 for the purpose of solving the problems of conventional ozone generation technology. Specifically, when ozone is generated, if the energy given as a result of the combination of oxygen molecules and oxygen atoms exceeds the energy required to generate ozone, ozone becomes an unstable excited state and easily decomposes. Although the ozone generation efficiency may be reduced, in the technique described in Non-Patent Document 1, when a third body (catalytic agent) is arranged on the surface of the electrode, oxygen molecules and oxygen atoms are combined. As a result, even if the energy given exceeds the energy required for ozone generation, excess energy can be immediately transferred to the third body, so that the generated ozone remains in an unstable excited state. It can be surely prevented. Thereby, since the produced | generated ozone can be stabilized, the improvement of ozone production efficiency can be aimed at.

  In addition, the ozone generator described in Patent Document 2 is configured so that the expanded metal is sandwiched between small parallel plates, and antimony as a third body is deposited on the surface of the expanded metal to form a catalyst electrode. An antimony electrode is formed.

JP 2003-146622 A JP 2007-217229 A

Consideration of ozone generation method using metal catalysts (2005 Annual Conference of the Institute of Electrical Engineers of Japan, March 17, 2005)

In the technology of ozone generation, the mechanism of the discharge part and the mechanism of ozone generation have been considered individually and have not been sufficiently studied. In particular, when discharge is performed using air as a raw material, nitrogen gas is also discharged, so that by-products such as NOx are generated and electric power cannot be efficiently used for generating ozone. In addition, even in an ozone generator using oxygen gas (pure oxygen), if ozone is continuously generated using only oxygen gas, the ozone generation efficiency is temporarily increased and the ozone concentration is increased. After a certain period of time, ozone can no longer be generated. Such a phenomenon is due to nitrogen acting as a catalyst for promoting ozone generation. Therefore, in order not to stop the ozone generation, about 2% of nitrogen is added in advance to pure oxygen, which is the raw material gas, to reduce the efficiency and operate while generating byproducts such as NOx.
That is, ozone is generated in the presence of nitrogen without fully recognizing the action of the third substance such as nitrogen, and the ozone generation efficiency is lowered.

  Therefore, it is conceivable to apply the technique described in Non-Patent Document 1 described above to the coaxial cylindrical electrode described above. When antimony as a third body is deposited on the surface of the expanded metal as described in Patent Document 2, the electrode is covered with antimony so that the coating is stably formed, and the electrode is discharged. However, when antimony is vapor-deposited on the inner wall surface of a large coaxial cylindrical electrode, the antimony is easily peeled off by discharge.

  Moreover, the coaxial cylindrical electrode configuration described in Patent Document 1 described above cannot sufficiently improve the ozone generation efficiency.

  In other words, when a catalytic metal is used for a coaxial cylindrical electrode, an electrode configuration is desired that does not easily peel off due to discharge and has an ozone generation efficiency that is even better than before.

  Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide an ozone generation method and apparatus using a coaxial cylindrical catalyst electrode that promotes ozone generation by contacting discharged oxygen gas. And

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

That is, the ozone generation method using the coaxial cylindrical catalyst electrode according to claim 1 is:
A cylindrical dielectric,
A cylindrical electrode that is coaxial with the cylindrical dielectric and arranged on the outside so as to have a predetermined gap with respect to the outer peripheral surface of the dielectric, and
An ozone generation method for generating ozone by supplying oxygen to the gap and discharging the electrode,
A plurality of protrusions are formed on a surface of the cylindrical electrode facing the outer peripheral surface of the dielectric, and a catalytic metal is coated thereon.

The ozone generator using the coaxial cylindrical catalyst electrode according to claim 2 comprises:
A cylindrical dielectric,
A cylindrical electrode that is coaxial with the cylindrical dielectric and arranged on the outside so as to have a gap at a predetermined interval with respect to the outer peripheral surface of the dielectric, and
An ozone generator that generates ozone by supplying oxygen to the gap and discharging the electrode,
A plurality of protrusions are formed on a surface of the cylindrical electrode facing the outer peripheral surface of the dielectric, and a catalytic metal is coated thereon.

  As effects of the present invention, the following effects can be obtained.

  According to claim 1, a plurality of protrusions are formed on a surface of the electrode that faces the outer peripheral surface of the dielectric, and a catalyst metal is coated to prevent the catalyst metal film from being peeled off and a discharge location is specified as the protrusion. As a result, the ozone generation efficiency can be improved.

  According to a second aspect of the present invention, a plurality of protrusions are formed on a surface of the electrode facing the outer peripheral surface of the dielectric and a catalyst metal is coated to prevent the catalyst metal film from being peeled off and a discharge location is specified as the protrusion. As a result, the ozone generation efficiency can be improved.

The schematic diagram which shows the whole structure of the test apparatus which concerns on this embodiment. It is a figure which shows a catalyst electrode type reactor, (a) is a front view, (b) is a side view. AA arrow sectional drawing in Fig.2 (a). The perspective view which shows the electrode which has protrusion. The front view which shows the electrode which has protrusion. The enlarged view of the B section in FIG. It is a figure which shows the electrode which has protrusion, (a) is side sectional drawing, (b) is a side view. The partially broken side view which shows the internal structure of the reactor for a comparison. The enlarged view of A part in FIG. Side surface sectional drawing which shows the clearance gap between a catalyst electrode and a dielectric material. Side surface sectional drawing which shows the clearance gap between the electrode for a comparison and a dielectric material. The figure which shows the ozone concentration change with respect to the input electric power at the time of the electrode for a comparison application. The figure which shows the ozone production efficiency with respect to the input electric power at the time of the electrode for a comparison application. The figure which shows the ozone concentration change with respect to the input electric power at the time of the electrode application which concerns on this embodiment. The figure which shows the ozone production efficiency with respect to the input electric power at the time of the electrode application which concerns on this embodiment.

  Next, embodiments of the invention will be described.

The overall configuration of a catalytic electrode type ozone generation test apparatus, which is an example of an ozone generation apparatus, will be described with reference to FIG.
In addition, in the member and apparatus etc. which have the same shape and function, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIG. 1, a catalytic electrode type ozone generation test apparatus 1 (hereinafter referred to as test apparatus 1) includes an oxygen supply means 2, an ozone generator 3, a cooling means 4, an ozone concentration meter 5, a power source 6, and the like. Is done.

  The oxygen supply means 2 is means for supplying oxygen that is a raw material gas for ozone generation to the ozone generator 3, and mainly comprises an oxygen gas cylinder (not shown), a stop valve 7, and a gas flow rate control device 8. Is done. The oxygen gas cylinder is connected to a gas flow rate control device 8 through a pipe and a stop valve 7. The gas flow rate control device 8 is connected to the ozone generator 3 through an oxygen gas supply pipe 9. The oxygen gas supply pipe 9 is a branch pipe that branches in two directions in the middle of the oxygen gas supply pipe 9, and a switching valve 9a is provided at a portion where the branch pipe branches. By switching, oxygen can be supplied to either one of the two pipes. Thus, it becomes possible to supply a predetermined amount of oxygen from the oxygen gas cylinder to the ozone generator 3 by operating the stop valve 7, the gas flow rate control device 8 and the switching valve 9a.

  The ozone generator 3 is a means for generating ozone by discharging the oxygen supplied by the oxygen supply means 2, and mainly comprises a catalyst electrode type reactor 10 and a comparative reactor 11. .

The catalytic electrode type reactor 10 (see FIG. 2) is an ozone generating means provided with a catalytic electrode 15 (hereinafter referred to as electrode 15) which is an electrode (discharger) coated with a catalytic metal, as shown in FIG. Further, a cylindrical dielectric 14 and a cylindrical electrode arranged so as to be coaxial with the cylindrical dielectric 14 and with the tip of the protrusion 16 (see FIG. 5) in contact with the outer peripheral surface of the dielectric 14 15. Further, in the state where the tip of the protrusion 16 is arranged so as to be in contact with the dielectric 14, a gap S is provided as shown in FIG. Both ends of the electrode 15 communicate with the oxygen gas supply pipe 9 described above.
The dielectric 14 is an iron hollow cylindrical body, and a predetermined ceramic film is formed on the outer peripheral surface thereof. Further, at a predetermined position on the outer peripheral surface of the dielectric 14, the electrode 15 is held so that the axial centers of the dielectric 14 and the electrode 15 are the same when the dielectric 14 is inserted into the electrode 15. A convex holding part (not shown) having a predetermined height is provided.
The electrode 15 is a brass cylindrical body, and as shown in FIG. 4, a plurality of protrusions 16 are formed on the surface of the cylindrical electrode 15 facing the outer peripheral surface of the dielectric 14, and antimony that is a catalytic metal. Is a film (in this embodiment, a film formed by vacuum deposition). That is, the cylindrical electrode 15 has a shape in which the inner wall surface of the electrode 15 is threaded in a spiral shape as shown in FIG. A plurality of protrusions 16 are continuously provided along the line. As shown in FIGS. 5 and 6, the protrusion 16 is formed in an uneven shape (saw blade shape) when viewed from the front. The inner diameter of the cylindrical electrode 15 (the inner diameter along the tip of the protrusion 16) is slightly larger than the diameter of the dielectric 14.
The catalyst metal is not particularly limited to antimony, and may be any metal having a catalytic action for promoting ozone generation. For example, bismuth or the like may be used. It may be a mixture of

  Thus, by arranging the cylindrical electrode 15 so as to be coaxial (concentric) and in contact with the outer peripheral surface of the dielectric 14, a space for discharging can be controlled. The oxygen supply means 2 can supply oxygen at a predetermined flow rate to the gap S of the saw blade portion through the oxygen gas supply pipe 9 communicating with the gap S.

  In addition, one side of an ozone gas discharge pipe 13 which is a two-way branch pipe is connected to the downstream side of the catalyst electrode type reactor 10 in order to discharge ozone gas and the like generated in the catalyst electrode type reactor 10. A switching valve 13 a is provided at a portion where the branch pipe branches, and the other end of the ozone gas discharge pipe 13 is connected to the ozone concentration meter 5.

Unlike the electrode 15 of the catalytic electrode reactor 10, the comparative reactor 11 is an ozone generating means provided with a comparative electrode 25 that is an electrode (discharger) that has no protrusions and is not coated with a catalytic metal. Yes, it is a reactor used to compare the characteristics of the electrodes of each of the catalytic electrode reactor 10 and the comparative reactor 11. As shown in FIGS. 8 and 9, the comparison reactor 11 includes a cylindrical dielectric body 14, which is the same as the catalytic electrode reactor 10, and is coaxial with the cylindrical dielectric body 14 and has an outer periphery of the dielectric body 14. And a cylindrical comparison electrode 25 arranged on the outside so as to have a gap S ′ (see FIG. 11) at a predetermined interval with respect to the surface.
Unlike the electrode 15 of the catalytic electrode reactor 10, the cylindrical comparison electrode 25 of the comparative reactor 11 is different from the electrode 15 of the catalytic electrode reactor 10, as shown in FIG. This is a conventional stainless steel electrode that does not have a plurality of protrusions and catalyst metal on the surface facing the outer peripheral surface. That is, the surface of the comparative electrode 25 that faces the outer peripheral surface of the dielectric 14 is a smooth inner wall surface that does not have undulations. The inner diameter of the cylindrical comparison electrode 25 is larger than the diameter of the dielectric 14.
In the comparative reactor 11, the other components other than the comparative electrode 25 are the same as those of the catalytic electrode reactor 10, and the description thereof is omitted.

  In this way, the cylindrical electrode 25 is disposed coaxially (concentrically) and with a gap S ′ having a predetermined interval with respect to the outer peripheral surface of the dielectric 14, thereby forming a cylindrical space (discharge). A gap S ′ that is a gap) can be formed. The oxygen supply means 2 can supply oxygen at a predetermined flow rate to the gap S ′ through the oxygen gas supply pipe 9 communicating with the gap S ′.

  The other side of the ozone gas discharge pipe 13 which is a two-way branch pipe is connected to the downstream side of the comparison reactor 11 in order to discharge the ozone gas generated in the comparison reactor 11. A switching valve 13 a is provided at a portion where the pipe branches, and the other end of the ozone gas discharge pipe 13 is connected to the ozone concentration meter 5. That is, by operating this switching valve 13a, it is possible to connect either the catalytic electrode type reactor 10 or the comparative reactor 11 and the ozone concentration meter 5 through the ozone gas discharge pipe 13. Yes, the exhaust gas sent from one of the connected reactors is introduced into the measuring unit 5a of the ozone concentration meter 5 to measure the ozone concentration, and the ozone concentration measured by the measuring unit 5a is converted into ozone. It can be displayed on the display unit 5b of the densitometer 5.

  That is, in the ozone generator 3, either the catalyst electrode type reactor 10 or the comparison reactor 11 is selected, and the gap S formed by the electrode 15 and the dielectric 14 included in the catalyst electrode type reactor 10. Alternatively, oxygen can be supplied to the gap S ′ formed by the comparison electrode 25 and the dielectric 14 included in the comparison reactor 11, and ozone can be generated by discharging the oxygen. Become. The generated ozone gas is sent to the ozone concentration meter 5 through the ozone gas discharge pipe 13, and the ozone concentration is measured.

  The ozone generator 3 includes a cooling means 4 for cooling the catalytic electrode type reactor 10 and the comparative reactor 11 as shown in FIG.

  The cooling means 4 includes a cooling water supply device (not shown), a cooling water introduction pipe 4a, a circulation pipe 4b, and a cooling water discharge pipe 4c. Thereby, the cooling water is supplied from the cooling water inlet (stop valve) by the cooling water supply device, passes through the inside of the catalytic electrode type reactor 10 via the cooling water introduction pipe 4a, and downstream of the catalytic electrode type reactor 10 Is circulated to the upstream side of the comparative reactor 11 through the circulation pipe 4b, passes through the comparative reactor 11, and is cooled through the cooling water discharge pipe 4c connected to the downstream side of the comparative reactor 11. The cooling water discharged from the water outlet (stop valve) is recovered by the cooling supply device, and the temperature of the ozone generator 3 (catalyst electrode type reactor 10, comparative reactor 11) is adjusted. It is possible to adjust. A power source 6 for applying a voltage to the electrodes 15 and 25 in the ozone generator 3 is connected to the ozone generator 3 via an inverter 17. The power source 6 can input predetermined power to the electrodes 15 and 25 of the catalyst electrode type reactor 10 and the comparison reactor 11, and the input power can be set to a predetermined value as appropriate.

  When ozone is generated by the catalytic electrode type reactor 10 in the ozone generator 3 by configuring the test apparatus 1 in this way, oxygen is supplied to the catalytic electrode type reactor 10 to discharge the generated ozone. For this purpose, the switching valves 9a and 13a are operated to the side communicating with the catalytic electrode type reactor 10, and high-purity oxygen gas is caused to flow from the oxygen gas cylinder to the oxygen gas supply pipe 9 by the gas flow rate control device 8, thereby It introduce | transduces into the clearance gap S of the type | formula reactor 10. FIG. Then, the oxygen gas introduced into the gap S of the catalytic electrode reactor 10 is discharged by the electrode 15 in accordance with a predetermined input power to generate a predetermined amount of ozone gas. The ozone gas is introduced into the ozone concentration meter 5 from the ozone gas discharge pipe 13 and the ozone concentration is measured.

  On the other hand, when ozone is generated by the comparative reactor 11 in the ozone generator 3, the switching valves 9a and 13a are used for the comparative reaction in order to supply oxygen to the comparative reactor 11 and discharge the generated ozone. By operating to the side communicating with the reactor 11, high-purity oxygen gas is caused to flow from the oxygen gas cylinder to the oxygen gas supply pipe 9 by the gas flow rate control device 8, and into the gap S ′ that is the cylindrical space of the comparison reactor 11. And introduce. The oxygen gas introduced into the gap S ′ of the comparison reactor 11 is discharged by the comparison electrode 25 in accordance with a predetermined input power to generate a predetermined amount of ozone gas. The ozone gas is introduced into the ozone concentration meter 5 from the ozone gas discharge pipe 13 and the ozone concentration is measured.

That is, the test apparatus 1 according to the present embodiment has a configuration in which a reactor having different electrodes is provided in order to compare the ozone generation efficiency due to the difference in electrode form. And the test apparatus 1 can compare the ozone concentration by the difference of an electrode by one oxygen supply means 2 and one ozone concentration meter 5 by operating the switching valves 9a and 13a. The catalyst electrode type reactor 10 (electrode 15) and the comparison reactor 11 (electrode 25) are configured to perform test measurement for comparing ozone generation efficiency under the same test conditions.
Note that the test apparatus 1 according to the present embodiment is configured with a reactor having different electrodes in order to perform a comparison test of ozone generation efficiency due to the difference in electrode form. It is not necessary to provide the comparative reactor 11 as a configuration of the ozone generator for generating the gas.
The test results obtained by applying the catalytic electrode reactor 10 (electrode 15) or the comparative reactor 11 (electrode 25) to generate ozone and measuring each ozone concentration are shown as examples below.

  Next, ozone was generated by each reactor of the catalytic electrode reactor 10 and the comparative reactor 11 in the test apparatus 1 of the present embodiment, and the ozone concentration and the ozone production efficiency with respect to the input power in each reactor were measured.

First, the oxygen supplied to the comparative reactor 11 of the ozone generator 3 was discharged to generate ozone. In this way, the ozone concentration relative to the input power when the comparative reactor 11 was applied was measured (see FIG. 12).
FIG. 12 is a plot of the ozone concentration (g / Nm ³ ) measured at each input power (100 to 180 W) while changing the oxygen supply amount to the comparative reactor 11 (the oxygen shown in FIG. 12). The supply amounts are: ◇: 0.5 l / min, □: 1.0 l / min, Δ: 2.5 l / min, ○: 5.0 l / min).
In FIG. 12, the horizontal axis represents input power (W), and the vertical axis represents ozone concentration (g / Nm ³ ).
Moreover, based on the ozone concentration change shown in FIG. 12, the ozone production efficiency change which is the ozone generation amount (production amount) per electric power consumption was calculated | required (refer FIG. 13).
FIG. 13 shows the ozone production efficiency (g / kWh) at each input power (100 to 180 W) obtained by changing the oxygen supply amount to the comparative reactor 11 and plotted (the oxygen shown in FIG. 13). The supply amounts are: ◇: 0.5 l / min, □: 1.0 l / min, Δ: 2.5 l / min, ○: 5.0 l / min).
In FIG. 13, the horizontal axis represents input power (W), and the vertical axis represents ozone production efficiency (g / kWh).

Next, the oxygen supplied to the catalytic electrode type reactor 10 of the ozone generator 3 was discharged to generate ozone. Thus, the ozone concentration with respect to the input power to the catalytic electrode reactor 10 was measured (see FIG. 14).
FIG. 14 is a graph in which the ozone concentration at each input power (100 to 160 W) was measured while changing the oxygen supply amount to the catalytic electrode type reactor 10 (the oxygen supply amount shown in FIG. : 0.5 l / min, □: 1.0 l / min, ▪: 2.0 l / min, Δ: 2.5 l / min, ○: 5.0 l / min.
In FIG. 14, the horizontal axis represents input power (W), and the vertical axis represents ozone concentration (g / Nm ³ ).
Moreover, the ozone production efficiency change which is the ozone generation amount per power consumption was calculated | required based on the ozone concentration change shown in FIG. 14 (refer FIG. 15).
FIG. 15 shows the ozone production efficiency (g / kWh) at each input power (100 to 160 W) obtained by changing the oxygen supply amount to the catalytic electrode reactor 10 and plotted (as shown in the upper part of FIG. 15). The oxygen supply amounts are: ◇: 0.5 l / min, □: 1.0 l / min, ■: 2.0 l / min, Δ: 2.5 l / min, ○: 5.0 l / min.
In FIG. 15, the horizontal axis represents input power (W), and the vertical axis represents ozone production efficiency (g / kWh).
The following compares ozone concentration change and ozone production efficiency change when the catalytic electrode reactor 10 (electrode 15) is applied, and ozone concentration change and ozone production efficiency change when the comparative reactor 11 (electrode 25) is applied. The results will be described.

  As a result, the ozone concentration and the ozone production efficiency are compared for each input power when the catalytic electrode type reactor 10 and the comparative reactor 11, that is, the electrode 15 and the comparative electrode 25 are applied when generating ozone. Then, when the input power is 100 W in the ozone concentration change (see FIGS. 12 and 14), the catalytic electrode type reactor 10 (electrode 15) supplies oxygen in comparison with the comparative reactor 11 (electrode 25). The ozone concentration in the amount increases, and it can be said that the electrode 15 generates ozone more efficiently. Further, when comparing ozone production efficiency (see FIGS. 13 and 15), the catalytic electrode type reactor 10 (electrode 15) has higher ozone production efficiency than the comparison reactor 11 (electrode 25) at each input power. It can be seen that there is a clear improvement (about twice when the input power is 100 W). It is considered that a large amount of ozone was generated at the same input power by applying the electrode 15 coated with antimony while forming the plurality of protrusions 16 on the inner wall surface of the cylindrical electrode. From this result, an ozone generation method and an ozone generation apparatus that can easily improve the ozone generation efficiency simply by changing the electrode configuration without changing the basic design of the coaxial cylindrical ozone generator by applying the electrode 15 Can be provided.

  That is, the test apparatus 1 (catalyst electrode reactor 10) according to the present embodiment includes a cylindrical dielectric 14 and the same axis coaxial with the cylindrical dielectric 14 and with respect to the outer peripheral surface of the dielectric 14. A cylindrical electrode 15 disposed on the outside so that the protrusion 16 contacts, oxygen is supplied to the gap S formed by inserting the electrode 15 through the dielectric 14, An ozone generator for generating ozone by discharging an electrode 15, wherein a plurality of protrusions 16 are formed on a surface of the cylindrical electrode 15 facing the dielectric 14, and antimony which is a catalytic metal is coated It is a thing. In this way, by forming the plurality of protrusions 16 on the surface of the electrode 15 that faces the outer peripheral surface of the dielectric 14 and coating the antimony that is the catalytic metal, the antimony coating that is the catalytic metal is prevented from being peeled off. In addition, the ozone generation efficiency can be improved by specifying the discharge location on the protrusion 16.

  Further, the electrode 15 included in the catalytic electrode type reactor 10 according to the present embodiment has the protrusion 16 on the inner wall surface, thereby limiting the discharge point on the surface (discharge surface) facing the dielectric 14 in the electrode 15. It is possible to fit within the range. That is, the discharge point in the electrode 15 is limited to a range near the apex of the protrusion 16 that is a portion closer to the dielectric 14 side. As a result, the discharge location is in the vicinity of the protrusion 16, and oxygen atoms are generated from oxygen molecules by the discharge at the discharge location, and the oxygen atoms are combined with the supplied oxygen molecules to generate ozone. That is, the comparison electrode 25 that is a cylindrical electrode that has been used conventionally has both discharge locations and ozone generation locations, whereas the electrode 15 has a discharge surface on the electrode 15 (on the opposite side of the dielectric 14). It is thought that the fact that the discharge location was specified by the electrode configuration in which the protrusions 16 were provided on the surface) and that the discharge location and the ozone generation location were separated without being mixed contributed to the improvement of the ozone generation efficiency.

  In addition, the electrode 15 of the catalytic electrode reactor 10 according to the present embodiment is provided with a protrusion 16 on the discharge surface of the electrode 15 (on the opposite surface of the dielectric 14), so that the catalyst metal with respect to the electrode base metal can be obtained. Since the adhesion can be improved (because the protrusion 16 is provided to improve the adhesion by increasing the surface area, so-called anchor effect is obtained), antimony, which is a catalyst metal coated by vacuum deposition, is peeled off. Can be prevented.

  The electrode 15 according to the present embodiment has a plurality of protrusions 16 on its inner wall surface, and has antimony as an example of a catalytic metal that promotes ozone generation on the inner wall surface as a deposited thin film. The generation of ozone is promoted by contacting the discharged oxygen gas with the gas. In the generation of ozone from the oxygen source, it is not necessary to add nitrogen to pure oxygen as a catalyst simply by changing the electrode to the electrode 15 having the antimony coating according to the present embodiment, and nitrogen is mixed with nitrogen gas or supply gas. In addition, the ozone generation efficiency can be increased and ozone that does not contain nitrogen oxides (NOx) can be produced with high efficiency.

1 Catalytic electrode type ozone generation test equipment 14 Dielectric 15 Catalytic electrode 16 Protrusion S Gap

Claims (2)

A cylindrical dielectric,
A cylindrical electrode that is coaxial with the cylindrical dielectric and arranged on the outside so as to have a predetermined gap with respect to the outer peripheral surface of the dielectric, and
An ozone generation method for generating ozone by supplying oxygen to the gap and discharging the electrode,
A method for generating ozone by a coaxial cylindrical catalyst electrode, wherein a plurality of protrusions are formed on a surface of the cylindrical electrode facing the outer peripheral surface of the dielectric and a catalyst metal is coated. A cylindrical dielectric,
A cylindrical electrode that is coaxial with the cylindrical dielectric and arranged on the outside so as to have a gap at a predetermined interval with respect to the outer peripheral surface of the dielectric, and
An ozone generator that generates ozone by supplying oxygen to the gap and discharging the electrode,
An ozone generator using a coaxial cylindrical catalyst electrode, wherein a plurality of protrusions are formed on a surface of the cylindrical electrode that faces the outer peripheral surface of the dielectric, and a catalyst metal is coated.

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