Ozone-generating discharge tube

Abstract

To provide an ozone-generating discharge tube of a quartz triple tube structure, enabling a worker to replace a component thereof and to easily carry out maintenance work, when a part of a triple tube is broken.SOLUTION: An ozone-generating discharge tube 1 of a silent discharge type for generating ozone by applying a voltage to a space part has at least an inner quartz tube 2, a center quartz tube 3, and an outer quartz tube 4 which are coaxially disposed, wherein an outer cooling water passage 22 is provided in a gap between the center quartz tube 3 and the outer quartz tube 4, an ozone-generating gas passage 25 is provided in a gap between the center quartz tube 3 and the inner quartz tube 2, an inner cooling water passage 21 is provided in an inner space 2b of the inner quartz tube 2, cap members 5 for fixing both ends of the inner quartz tub 2, the center quartz tube 3, and the outer quartz tube 4 are provided, and a shaft member 6 coaxially disposed in the inner space 2b of the inner quartz tube 2, and the cap members 5 are fixed to both ends of the shaft member 6.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a technology for a discharge tube for generating ozone. [Background technology]

[0002] Conventionally, technology has been developed for a double-sided water-cooled quartz discharge tube that is capable of generating more ozone on a scale similar to that of a triple quartz tube structure with an inner surface water-cooled and an outer surface air-cooled (see, for example, Patent Document 1).

[0003] Conventional discharge tubes with triple quartz tube structure are characterized by being water-cooled on both the inside and outside. In particular, cooling water on the high voltage side is supplied and discharged through insulating piping. That is, cooling water is circulated in the gap between the outer tube and the central quartz tube, and cooling water is circulated inside the inner quartz tube, a high AC voltage is applied between the two cooling waters, a high AC electric field is formed in the gap between the inner quartz tube and the central quartz tube, and silent discharge is generated to generate ozone (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2009-91209 A Summary of the Invention [Problem to be solved by the invention]

[0005] In a conventional triple quartz tube structure, a central quartz tube is inserted into an outer tube, and an inner quartz tube is inserted into the central quartz tube to form a triple tube. At this time, the quartz tubes are welded to each other at both ends.

[0006] The quartz tube is made of a hard but brittle material, which makes it difficult to process and can be damaged during maintenance. In addition, since the quartz tubes are welded to each other at both ends, even if the outer tube is damaged, the entire quartz triple tube cannot be used.

[0007] In view of the above problems, the present invention provides an ozone generating discharge tube having a triple quartz tube structure, which allows replacement of parts even if part of the triple tube is damaged, thereby facilitating maintenance. [Means for solving the problem]

[0008] The problem to be solved by the present invention has been described above, and the means for solving this problem will now be described.

[0009] That is, in the present invention, a silent discharge type ozone generating discharge tube is provided which generates ozone by applying a voltage to a gap, The device has at least an inner quartz tube, a central quartz tube, and an outer tube arranged with a common axis, An outer cooling water passage is provided in the gap between the central quartz tube and the outer tube, an ozone generating gas passage is provided in the gap between the central quartz tube and the inner quartz tube, and an inner cooling water passage is provided in the internal space of the inner quartz tube; providing cap members for fixing both ends of the inner quartz tube, the central quartz tube, and the outer tube; a shaft member is provided in the internal space of the inner quartz tube, the shaft member being arranged with a common axis; The cap members are fixed to both ends of the shaft member.

[0010] In the present invention, an internal cooling water passage may be provided inside the shaft member.

[0011] In the present invention, the shaft member may be formed from a material having electrical conductivity and corrosion resistance, and may be provided on a side surface thereof with a cooling water passage hole communicating with the internal cooling water passage.

[0012] In the present invention, the cap member may be formed of a material having insulating properties and corrosion resistance. Effect of the Invention

[0013] The present invention has the following advantages.

[0014] In the present invention, even if one of the triple tubes is damaged, the ozone generating discharge tube can be repaired by simply replacing the damaged tube, thereby reducing costs. [Brief description of the drawings]

[0015] [Figure 1] FIG. 2 is a front cross-sectional view showing the ozone generating discharge tube according to the first embodiment. [Diagram 2] FIG. 2 is a cross-sectional view showing a shaft member and an inner quartz tube according to the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Next, an embodiment of the invention will be described. First, the overall configuration of an ozone generating discharge tube 1 having a triple quartz tube structure according to one embodiment of the present invention will be described with reference to FIG. The ozone generating discharge tube 1 is a quartz discharge tube with water cooling on both sides, and is a discharge tube for a silent discharge ozone generator that generates ozone by applying a voltage to the gap. Quartz used in quartz discharge tubes has excellent heat resistance and transparency, and is highly resistant even at high operating temperatures. The ozone discharge performed in the ozone generating discharge tube 1 is performed by introducing a gas containing oxygen into the inside of the ozone generating discharge tube 1 and applying a voltage to the electrodes to generate silent discharge, thereby giving activation energy to the oxygen to generate ozone. In order to efficiently generate ozone by silent discharge, efficient cooling of the discharge tube is important. Therefore, the discharge tube in this embodiment is efficiently cooled by having a triple tube structure in which cooling water flows inside and outside the tube where silent discharge is performed.

[0017] Furthermore, by making the cooling water itself conductive, it has become possible to introduce a fluid that functions both as cooling water and as an electrode. This allows the electrode itself to be cooled efficiently. That is, by arranging a wire (outer electrode wire 31) that serves as an electrode in the outer cooling water passage 22 and arranging a shaft member 6 that serves as an electrode in the inner cooling water passage 21, a voltage is applied in the fluid, which serves as an electrode.

[0018] The configuration of the ozone generating discharge tube 1 according to this embodiment will be described below with reference to Fig. 1. Fig. 1 is a cross-sectional view of the ozone generating discharge tube 1, with the front side facing the paper and the rear side facing the paper. The left-right direction of the paper is the left-right direction, and the up-down direction of the paper is the up-down direction.

[0019] The ozone generating discharge tube 1 has an inner quartz tube 2, a central quartz tube 3, and an outer tube 4, which are arranged with a common axis. The inner quartz tube 2 is a thin cylinder, and is configured to be longer than the central quartz tube 3 and the outer tube 4. The inner quartz tube 2 has an open end 2a which is covered by a cap member 5.

[0020] The central quartz tube 3 is a cylinder having an inner diameter larger than that of the inner quartz tube 2, and is configured to be longer than the outer tube 4. The central quartz tube 3 has an open end 3 a which is connected to a gas inlet 11 and a gas outlet 12 provided in the cap member 5 .

[0021] The outer tube 4 is a tube having an inner diameter larger than that of the central quartz tube 3, and is configured to have the shortest length. In this embodiment, the outer tube 4 is made of quartz, similar to the inner quartz tube 2 and the central quartz tube 3.

[0022] The outer tube 4 is not limited to being made of quartz, and may be made of a material having transparency and heat resistance, such as borosilicate glass. When borosilicate glass is selected, the transparency ensures internal visibility. It is also possible to form the outer pipe 4 from a non-brittle material such as metal. In this case, the outer pipe 4 is a metal pipe, and although the interior cannot be seen, it has excellent resistance to brittleness. The outer pipe 4 has an open end 4 a which is connected to a cooling water inlet 14 and a cooling water outlet 15 for the outer cooling water provided in the cap member 5 .

[0023] Further, in the internal space 2b of the inner quartz tube 2, a shaft member 6 is provided, which is arranged with a common axis. The shaft member 6 is made of a metal material having excellent electrical conductivity, corrosion resistance, heat resistance, and abrasion resistance. For example, the shaft member 6 is made of stainless steel. The shaft member 6 penetrates the cap member 5 and protrudes from the upper and lower ends, and is fixed by attaching joint members 7. In this way, the inner quartz tube 2, the central quartz tube 3, and the outer tube 4 are sandwiched from both ends by the cap member 5.

[0024] The cap member 5 is a member that covers the ends of the inner quartz tube 2, the central quartz tube 3, and the outer tube 4, and is made of an alloy containing iron. In this embodiment, the cap member 5 is made of FEPT. FEPT is an alloy containing iron and platinum, and has insulating properties. A shaft through hole 5a for passing the shaft member 6 through is provided in the center of the cap member 5. In addition, a central electrode wire 16 for passing electricity to the shaft member 6 that serves as the central electrode is connected to the underside of the lower cap member. When a voltage is applied to the central electrode wire 16, electricity is not passed through the cap member 5, which has insulating properties, but is passed through the shaft member 6 that is in contact with it.

[0025] The cap member 5 is not limited to the present embodiment as long as it is made of a material having insulating properties and corrosion resistance. For example, engineering ceramics may be used as another material.

[0026] Next, the configuration of the cooling water passages 21, 22 of the ozone generating discharge tube 1 will be described with reference to FIG. In this embodiment, the cooling water passages 21, 22 are composed of an inner cooling water passage 21 that cools the ozone generating gas passage 25 from the inside, and an outer cooling water passage 22 that cools the ozone generating gas passage 25 from the outside. The inner cooling water passage 21 is provided inside the inner quartz tube 2. In this embodiment, the inner cooling water passage 21 is provided in the shaft member 6 arranged inside the inner quartz tube 2.

[0027] An internal cooling water passage 6a is provided in the center of the shaft member 6. The internal cooling water passage 6a is provided from the upper and lower ends to the middle of the shaft member 6. A cooling water passage hole 6b communicating with the inner cooling water passage 21 is provided on the side of the shaft member 6. The cooling water passage hole 6b is a hole of about 1 to 10 mm, and is a hole for allowing cooling water to flow out from the internal cooling water passage 6a to the outside and for allowing cooling water to flow from the outside into the internal cooling water passage 6a. One cooling water passage hole 6b is provided corresponding to each of the upper and lower internal cooling water passages 6a.

[0028] The cooling water supplied to the inner cooling water passage 6a from the upper end of the shaft member 6 passes through the cooling water passage hole 6b and fills the inner space 2b of the inner quartz tube 2. As a result, the ozone generating gas passage 25 on the outside of the inner quartz tube 2 is cooled from the inside by the cooling water.

[0029] Moreover, the cooling water in the internal space 2b of the inner quartz tube 2 passes through the cooling water passage 6b and is discharged from the internal cooling water passage 6a to the lower end of the shaft member 6. This allows the entire ozone generating discharge tube 1 to be cooled while the shaft member 6, which is the central electrode, is cooled from the inside by the cooling water.

[0030] Further, the outer cooling water passage 22 is provided between the inner surface of the outer tube 4 and the outer surface of the central quartz tube 3. The cooling water inlet 14 and the cooling water outlet 15 provided in the cap member 5 are connected to the ends of the outer cooling water passage 22. Cooling water is introduced from the cooling water inlet 14 and filled in the outer cooling water passage 22. As a result, the ozone generating gas passage 25 inside the central quartz tube 3 is cooled from the outside by the cooling water. The outer cooling water passage 21 is provided in the gap between the central quartz tube 3 and the outer tube.

[0031] In this manner, by supplying cooling water to the outer cooling water passage 22 and the inner cooling water passage 21 to cool them, the ozone generating gas passage 25 provided in the gap between the central quartz tube 3 and the inner quartz tube 2 is cooled.

[0032] Next, a method for generating ozone using the ozone generating discharge tube 1 will be described. Cooling water is introduced from a cooling water inlet 14 into an outer cooling water passage 22 provided in the gap between the outer tube 4 and the central quartz tube 3. The cooling water that has passed through the outer cooling water passage 22 is discharged from a cooling water outlet 15. Cooling water is also introduced into the inner quartz tube 2. In this embodiment, cooling water is introduced into the shaft member 6 provided inside the central quartz tube 3. More specifically, cooling water is introduced from the upper end of the shaft member 6 into the internal cooling water passage 6a provided inside. The cooling water introduced into the internal cooling water passage 6a is introduced into the internal space 2b of the inner quartz tube 2 through the upper cooling water passage hole 6b. Furthermore, the cooling water that has finished cooling in the internal space 2b is discharged from the internal cooling water passage 6a through the lower cooling water passage hole 6b to the lower end of the shaft member 6. A pipe (not shown) connected by a joint member 7 is connected to the lower end of the shaft member 67, and the cooling water is discharged to the outside through the pipe.

[0033] Next, the ozone generating gas is introduced from the gas inlet 11 for introducing the ozone generating gas into the ozone generating gas passage 25 provided in the gap between the central quartz tube 3 and the inner quartz tube 2. Here, the ozone generating gas is oxygen or a gas containing oxygen. Moreover, by starting the AC high voltage power supply, electricity is passed through the cooling water in the shaft member 6, which serves as the central electrode. Meanwhile, an outer electrode wire 31 is disposed in the outer cooling water passage 22 between the outer tube 4 and the central quartz tube 3. By starting the AC high voltage power supply, electricity is passed through the outer electrode wire, which serves as the outer electrode. As a result, discharge is generated in the ozone generating gas between the ozone generating gas passages 25, ozone is generated, and the ozone-containing gas is taken out from the gas outlet 12.

[0034] Next, a method for assembling the quartz triple tube will be described. First, the inner quartz tube 2, the central quartz tube 3, and the outer tube 4 are stacked coaxially. By configuring in this way, the inner quartz tube 2, the central quartz tube 3, and the outer tube 4 are arranged coaxially in this order. Next, the shaft member 6 is inserted inside the inner quartz tube 2. The shaft member 6 is arranged so as to be coaxial with the inner quartz tube 2.

[0035] Next, cap members 5 are fitted onto both ends of the triple tube. The cap members 5 are fitted so as to cover the end 2a of the inner quartz tube 2, the end 3a of the middle quartz tube 3, and the end 4a of the outer tube 4. A shaft through hole 5a is provided in the center of the cap member 5, and both ends of the shaft member 6 protrude outward from the shaft through hole 5a.

[0036] In this manner, with the cap members 5 fitted to both ends of the triple pipe, the coupling members 7 are attached to both ends of the shaft member 6. The coupling members 7 are components for further connection to external water supply pipes and drainage pipes, and are formed by a bite-type coupling. A bite-type coupling is a coupling that connects pipes by biting into them, and because the connection part is strong, it can withstand high pressure and high temperature.

[0037] Furthermore, by fastening the shaft member 6 with the joint member 7, the cap member 5 and the end of the triple tube fitted into the cap member 5 are in tight contact with each other. Furthermore, the seal members 41 provided on the outer surfaces of the inner quartz tube 2, the central quartz tube 3, and the outer tube 4 can prevent leakage of gas and liquid and provide a tight seal.

[0038] With this configuration, it is possible to replace only one of the inner quartz tube 2, the central quartz tube 3, and the outer tube 4 by removing the joint member 7 and the cap member 5. For example, if the outer tube 4 is damaged during use, it can be used again by removing the joint member 7, the cap member 5, and replacing the outer tube 4. In this way, maintenance of the quartz tube itself is made easier, and repair costs are reduced.

[0039] As described above, the ozone generating discharge tube 1 is a silent discharge type ozone generating discharge tube 1 that generates ozone by applying a voltage to a gap, and has at least the inner quartz tube 2, central quartz tube 3, and outer tube 4 arranged with a common axis. An outer cooling water passage 22 is provided in the gap between the central quartz tube 3 and the outer tube 4, an ozone generating gas passage 25 is provided in the gap between the central quartz tube 3 and the inner quartz tube 2, an inner cooling water passage 21 is provided in the internal space 2b of the inner quartz tube 2, cap members 5 are provided to fix both ends of the inner quartz tube 2, central quartz tube 3, and outer tube 4, a shaft member 6 arranged with a common axis is provided in the internal space 2b of the inner quartz tube 2, and cap members 5 are fixed to both ends of the shaft member 6.

[0040] With this configuration, by removing the joint member 7 and the cap member 5, it is possible to replace only one of the inner quartz tube 2, the central quartz tube 3, and the outer tube 4.

[0041] Moreover, it is preferable that the ozone generating discharge tube 1 is provided with an internal cooling water passage 6a inside the shaft member 6. With this configuration, it becomes easier to supply cooling water to the inner cooling water passage 21 by flowing the cooling water inside the shaft member 6. Moreover, the cooling water inside the shaft member 6 can also be used as the central electrode.

[0042] Moreover, it is preferable that the shaft member 6 is made of stainless steel and has a cooling water passage hole 6b formed on its side surface. With this configuration, the cooling water inside the shaft member 6 can also be used as the central electrode. Also, since it has corrosion resistance, it is possible to prevent deterioration due to the oxidizing effect of ozone.

[0043] Moreover, the cap member 5 is preferably made of a material having insulating properties and corrosion resistance. This configuration provides insulation and corrosion resistance, making it possible to prevent deterioration caused by the oxidizing effect of ozone. Also, by using an insulating material, it is possible to prevent discharge due to a short circuit.

[0044] 1. Ozone generating discharge tube 2 Inner quartz tube 3 Central quartz tube 4 Outer tube 5 Cap member 6 Shaft member 6a Internal cooling water passage 7 Joint members 11 Gas inlet 12 Gas outlet 14 Cooling water inlet 15 Cooling water outlet 21 Inner cooling water passage 22 Outside cooling water passage 25 Ozone generating gas passage

Claims

1. A silent discharge type ozone generating discharge tube that generates ozone by applying a voltage to a gap, The device has at least an inner quartz tube, a central quartz tube, and an outer tube arranged with a common axis, An outer cooling water passage is provided in the gap between the central quartz tube and the outer tube, an ozone generating gas passage is provided in the gap between the central quartz tube and the inner quartz tube, and an inner cooling water passage is provided in the internal space of the inner quartz tube; providing cap members for fixing both ends of the inner quartz tube, the central quartz tube, and the outer tube; a shaft member is provided in the internal space of the inner quartz tube, the shaft member being arranged with a common axis; The cap members are fixed to both ends of the shaft member.

1. A discharge tube for generating ozone.

2. An internal cooling water passage is provided inside the shaft member.

2. The discharge tube for generating ozone according to claim 1.

3. the shaft member is formed of a material having electrical conductivity and corrosion resistance, and a cooling water passage hole communicating with the internal cooling water passage is provided on a side surface of the shaft member; 3. The discharge tube for generating ozone according to claim 2.

4. The cap member is formed of a material having insulating properties and corrosion resistance.

4. The discharge tube for generating ozone according to claim 3.

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