JP2012126614A - Ozone generating apparatus and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ozone generating apparatus which can keep a discharge gap uniform, thereby having good ozone generation efficiency.SOLUTION: The ozone generating apparatus includes: a ground electrode tube; an oxygen side tube plate which holds one end of the ground electrode tube; an ozone side tube plate which holds the other end of the ground electrode tube; a water chamber body for forming a water chamber in which cooling water is caused to flow around the ground electrode tube; an oxygen header for supplying a raw material gas containing oxygen; and an ozone header for collecting generated ozone gas, wherein flanges are formed on both sides of the water chamber body, one of the flanges is fastened to the oxygen side tube plate with bolts, and the other is fastened to the ozone side tube plate with bolts.

Description

  The present invention relates to an ozone generator for generating ozone used for water treatment and the like, and more particularly to a structure of an ozone generator for generating ozone by discharge.

  There are various structures of ozone generators that generate ozone by electric discharge, but ozone generators used for water treatment and the like generally have a large capacity, for example, inside a can body that is a cylindrical container having a large diameter of m order. In addition, a configuration in which a large number of cylindrical discharge tubes having a small diameter on the order of cm are arranged in many cases is used. The number of discharge tubes arranged in one container is usually 100 or more, and there are very many such as about 1000. As a discharge tube, for example, a glass tube with a metal film formed on the inner surface is inserted as a high voltage electrode tube into a metal ground electrode tube, and the inner surface of the ground electrode tube and the outer surface of the high voltage electrode tube The thing of the structure which formed the discharge gap for making it discharge in between is used. A gas containing oxygen is caused to flow through the discharge gap, and an alternating high voltage is applied between the high-voltage electrode tube and the ground electrode tube to generate a discharge, whereby the gas containing oxygen is ozonized.

In the ozone generator that generates ozone by electric discharge, only about 10% of the input electric power is used for generating ozone, and the remaining about 90% is heat. The discharge gap where ozone is generated, that is, the discharge field, needs to be cooled because the ozone generation efficiency decreases as the temperature increases. As a cooling method, it was a general method to cool the outside of the ground electrode tube by water cooling. In order to allow cooling water to flow outside the ground electrode tube, the space between the body forming the water chamber (water chamber body) and the tube plate fixing the ground electrode tube, or between the ground electrode tube and the tube plate Since it is necessary to avoid (seal) water leakage and these members are generally made of metal, welding is often used as the most reliable sealing method (for example, Patent Document 1).

Special Table 2008-518877 Publication (Fig. 1)

Since the conventional ozone generator is configured as described above, the tube sheet is often curved due to welding distortion when the water chamber body and the tube sheet are welded. In addition, there is a problem that the degree of bending of the tube sheet varies depending on the skill of the person performing the welding. On the other hand, since the ground electrode tube is installed between the oxygen side tube plate and the ozone side tube plate and both ends are held, if the tube plate is curved, the ground electrode tube is also affected by the influence and is on the order of 1 to several mm. There was a problem of turning at. Recent ozone generators have a very short gap of 0.4 mm or less for high efficiency and high concentration, so even if the ground electrode tube is slightly bent, the gap is not uniform. Thus, there are problems such as a decrease in ozone generation efficiency and the inability to insert a high voltage electrode tube.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide an ozone generator having high assembly accuracy and high ozone generation efficiency. Another object of the present invention is to produce a highly accurate ozone generator regardless of the skill of the welding operator who assembles the can of the ozone generator.

  The present invention includes a ground electrode tube, an oxygen side tube plate that holds one end of the ground electrode tube, an ozone side tube plate that holds the other end of the ground electrode tube, and a ground electrode tube. An ozone generator comprising: a water chamber body for forming a water chamber for circulating cooling water; an oxygen header for supplying oxygen gas; and an ozone header for concentrating the generated ozone gas. Flange is formed on both sides, one of the flanges and the oxygen side tube sheet are bolted, and the other flange and the ozone side tube sheet are bolted.

  Since the ozone generator according to the present invention is configured as described above, in addition to less distortion of the tube sheet due to the assembly of the can body, which is the main body container of the apparatus, there is less variation in the assembly process, and the discharge There is an effect that the uniformity of the gap is increased, and as a result, an ozone generator having good ozone generation efficiency can be obtained.

It is sectional drawing which shows the structure of the can of the ozone generator by Embodiment 1 of this invention. It is a flowchart explaining the manufacturing method of the ozone generator by Embodiment 1 of this invention. It is a schematic block diagram for demonstrating operation | movement of the ozone generator by Embodiment 1 of this invention. It is sectional drawing which shows the structure of the can of the ozone generator by Embodiment 2 of this invention. It is a partial expanded sectional view which shows the part of D of FIG. 4 among the structures of the ozone generator by Embodiment 2 of this invention. It is a flowchart explaining the manufacturing method of the ozone generator by Embodiment 2 of this invention. It is a figure explaining the attachment structure of the oxygen header of the ozone generator by Embodiment 3 of this invention. It is a figure explaining the operating characteristic of the ozone generator by this invention.

Embodiment 1 FIG.
FIG. 1 is a cross-sectional view showing the structure of a can serving as a main body container of an ozone generator according to Embodiment 1 of the present invention. A first embodiment of the present invention will be described below with reference to FIG. In FIG. 1, reference numeral 1 denotes a ground electrode tube, which is fixed to an oxygen side tube plate 2 and an ozone side tube plate 3. The ground electrode tube 1 is formed of, for example, a stainless steel tube having an inner diameter of about 20 mm. The ground electrode tube 1 is fixed to the oxygen side tube plate 2 made of stainless steel by welding, and is expanded to the ozone side tube plate 3 made of stainless steel. It is fixed by. 4 is a stainless steel water chamber body for circulating cooling water therein, and body flanges 4b and 4c are welded to both ends of the water chamber body cylinder 4a. The water chamber body 4 includes a cooling water inlet 41 for introducing cooling water and a cooling water outlet 42 for discharging cooling water. The shape of the water chamber body 4 is preferably a cylinder. The body flanges 4b and 4c have holes for penetrating bolts on the circumference. Further, the outer diameter dimensions of the oxygen side tube sheet 2 and the ozone side tube sheet 3 are substantially the same as the outer dimensions of the body flanges 4b and 4c, and holes for bolt penetration on the circumference of the body flanges 4b and 4c. Bolt penetrating holes 2a and 3a are formed at positions facing 4d and 4e. Further, the O-side tube plate 2 and the ozone-side tube plate 3 are respectively formed with grooves for O-rings, and sealed between the body flanges 4b and 4c via the O-rings 2b and 3b, respectively. Yes.

Reference numeral 5 denotes an oxygen header for supplying a source gas containing oxygen. An oxygen header cylinder 5a having a source gas inlet 51 for introducing the source gas into the container is provided with a lid side flange 5b and a tube plate side flange. 5c is welded. The shape of the oxygen header 5 is preferably a cylinder. Similarly, reference numeral 6 denotes an ozone header for collecting ozone gas, and a lid side flange 6b and a tube plate side flange 6c are welded to an ozone ozone header cylinder 6a provided with an ozonized gas outlet 61 for taking out generated ozone. It has a structure. Here, the tube plate side flange 5 c and the lid side flange 5 b of the oxygen header 5 are inner flanges so as to be positioned inside the oxygen header 5. An O-ring groove is formed in the tube sheet side flange 5c of the oxygen header, and the space between the oxygen side tube sheet 2 is sealed by an O ring 5d. Further, a stop screw hole 5e is formed at a position facing the bolt penetration hole on the circumference of the body flange 4b. The reason for stopping the screw holes is to prevent the source gas from leaking from the bolt holes. On the other hand, an O-ring groove is also formed on the tube plate side flange 6c of the ozone header 6, and a bolt penetration hole 6e is formed at a position facing the bolt penetration hole on the circumference of the body flange 4c. The space between the ozone side tube sheet 3 is sealed by the O-ring 6d.

  Reference numeral 7 denotes a lid of the oxygen header 5, which is fastened with a bolt by a closed screw hole formed so that the raw material gas does not leak into the lid side flange 5 b of the oxygen header 5. Reference numeral 8 denotes a lid of the ozone header 6, which is fastened to the lid side flange 6 b of the ozone header 6 with a bolt. In this way, the entire can body is composed of the water chamber body 4, the oxygen header 5, the lid 7 of the oxygen header 5, the ozone header 6, the lid 8 of the ozone header 6, and the ground electrode tube 2 to which the ground electrode tube 1 is attached. And the ozone side tube plate 3.

  Next, a method for assembling the can body will be described. First, the water chamber body 4 is produced. After the body flanges 4b and 4c are welded to both ends of the water chamber body cylinder 4a, machining is performed to obtain planar accuracy with respect to the surfaces of the body flanges 4b and 4c that respectively contact the tube sheet. At this time, the parallelism and flatness of the body flanges 4b and 4c and the perpendicularity with respect to the axis of the water chamber body cylinder 4a are designated by a five-face processing machine or the like. Also, drill holes for bolt penetration. By doing in this way, even if the body flanges 4b and 4c are deformed due to welding distortion during welding, a desired accuracy can be obtained by subsequent machining. Similarly, with respect to the oxygen header 5 and the ozone header 6, the pipe plate side flanges 5 c and 6 c are welded to the header cylinders 5 a and 6 a, respectively, and then the flat surface processing, O-ring groove processing and drilling processing are performed. The oxygen side tube sheet 2 and the ozone side tube sheet 3 are also machined alone. Since machining is performed by itself, machining accuracy can be expected.

  The assembly process of the main part of the can body is shown in FIG. First, the ground electrode tube 1 is inserted into the ozone side tube plate 3 (ST1). Next, in a state where the ground electrode tube 1 is inserted into the ozone side tube plate 3, the water chamber body 4 is aligned with the ozone side tube plate 3 using, for example, positioning pins, and the ozone header 6 is also aligned with the bolt. The water chamber body 4, the ozone side tube sheet 3, and the ozone header 6 are joined together (ST2). Next, the oxygen side tube plate 2 is aligned with the water chamber body 4 using, for example, a positioning pin so that the ground electrode tube 1 is inserted (ST3), and the oxygen side tube plate 2 and the water chamber body 4 are aligned. Are coupled with bolts (ST4). In this example, the ground electrode tube 1 is first inserted into the ozone side tube plate 3 and then assembled. However, the oxygen side tube plate is not inserted into the ozone tube plate 3 first. 2 and the water chamber body 4 may be joined by a bolt (ST4), and then the ground electrode tube 1 may be inserted from the outside of the oxygen side tube plate 2 or the ozone side tube plate 3.

Thus, since the water chamber body 4, the ozone side tube plate 3, and the ozone header 6 that ensure sufficient processing accuracy as a single component are simply assembled by bolt fastening, deformation or the like does not occur in the tube plate. In the conventional ozone generator, since the water chamber body and the tube sheet or the tube sheet and the header are welded, there is a problem that the tube sheet is deformed due to welding distortion at the time of welding. Such a problem does not occur. Similarly, since the water chamber body 4 and the oxygen side tube plate 2 are simply assembled by bolt fastening, the tube plate is not deformed. Further, at the time of assembly, positioning with a positioning pin (not shown) or the like enables assembly with a desired accuracy even if there is a considerable clearance (backlash) in the bolt through hole.

As described above, the oxygen-side tube sheet 2 and the ozone-side tube sheet 3 can be assembled in a state where the parallelism of both is within the design accuracy while ensuring flatness without deformation. In this state, the expansion between the ground electrode tube 1 and the ozone side tube plate 3 is performed, and the ground electrode tube 1 and the ozone side tube plate 3 are joined by welding (ST5). The tube expansion is a method usually used as a processing method for a general shell-and-tube heat exchanger, and the tube (the ground electrode tube 1 in the present embodiment) tends to extend by about 1 mm. Since it is only inserted into the opposite oxygen side tube plate 2 and is in a free state (it can be freely extended), there is no fear that the ground electrode tube 1 is bent. However, the ground electrode tube 1 and the ozone side tube sheet 3 may be joined by welding. Next, the ground electrode tube 1 and the oxygen side tube plate 2 are joined by welding (ST6). This welding is a welding only at the mouth, and since the amount of heat input is very small, there is almost no welding distortion and there is no fear that the ground electrode tube 1 is bent.
Thus, the main part of the can body to which the ground electrode tube 1 is attached is completed.

Here, the operation principle and insulation of the ozone generator will be described with reference to FIG. FIG. 1 is a view showing a can body that is a container of an ozone generator, but FIG. 3 shows a high voltage electrode tube and an AC high voltage power source for operation as an ozone generator. 3, the same reference numerals as those in FIG. 1 denote the same parts. In FIG. 3, a high voltage electrode tube 10 is coaxially inserted into the ground electrode tube 1. Here, the high voltage electrode tube 10 is formed by forming a metal film on the inner surface of a glass tube having an outer diameter of about 20 mm by a method such as spraying, vapor deposition, plating or coating. Here, the outer diameter of the high voltage electrode tube 10 is smaller by about 0.6 mm than the inner diameter of the ground electrode tube 1, and a spacer (not shown) is provided outside the high voltage electrode tube 10. A discharge gap 11 of about 0.3 mm is formed between the inner surface and the outer surface of the high voltage electrode tube 10. The ozone header 6 side of the high voltage electrode tube 10 is closed, and the raw material gas supplied from the oxygen header 5 flows into the ozone header 6 through the discharge gap 11.

  Reference numeral 9 denotes an AC high-voltage power source, which supplies an AC high voltage of, for example, several kV to the metal film of the high-voltage electrode tube 10 by the power supply member 92 through the power supply line 90. On the other hand, the water chamber body 4, the oxygen side tube plate 2, and the ozone side tube plate 3 are electrically connected to each other by welding or expansion. The water chamber body 4 is grounded, and therefore, the ground electrode tube 1, the oxygen side tube plate 2, and the ozone side tube plate 3 are at ground potential. Similarly, the oxygen header 5 and the ozone header 6 are also electrically connected to the oxygen side tube plate 2 and the ozone side tube plate 3 and are at ground potential. Reference numeral 91 denotes an insulator, which is provided to insulate the high-voltage power supply line 90 from the oxygen header 5 because the oxygen header 5 is at ground potential. Since glass, that is, a dielectric exists between the metal film of the high-voltage electrode tube 10 and the ground electrode tube 1, so-called silent discharge occurs in the discharge gap 11 due to the applied AC high voltage, and the discharge gap The oxygen of the gas containing oxygen flowing through 11 is ozonized. Thus, the glass tube which formed the metal film in the inner surface is made into the high voltage electrode tube 10, and a glass tube serves as a structure and the dielectric material layer for silent discharge. In addition to glass, ceramics can be used as the dielectric, but glass is generally cheaper.

Next, the operation will be described. Oxygen, which is a source gas, is supplied from a source gas inlet 51. Here, oxygen is supplied from a liquid oxygen facility including a liquid oxygen tank, an evaporator, a pressure reducing valve, and the like (not shown). When ozone is generated from an oxygen raw material by discharge, it is generally known that a very small amount of nitrogen is required, and therefore a small amount of nitrogen (a flow rate within 1% of oxygen) needs to be supplied. On the other hand, oxygen may be produced using an oxygen production apparatus such as a PSA (pressure swing adsorption) apparatus. When oxygen is produced by an oxygen production apparatus, oxygen is generally produced in a state containing a small amount of nitrogen, so that it is not necessary to separately supply nitrogen. Oxygen, which is a raw material gas supplied from the raw material gas inlet 51, passes through the discharge gap 11 and is discharged from the ozonized gas outlet 61 to the outside of the ozone generator. Supplied and used.

  Here, when an AC high voltage is supplied from the AC high voltage power supply 9, a high voltage is applied between the high voltage electrode tube 10 and the ground electrode tube 1, and silent discharge occurs in the discharge gap 11. Then, part of the supplied oxygen becomes ozone, and a gas containing ozone is discharged from the ozonized gas outlet 61. Here, the cooling water is supplied from the cooling water inlet 41 and discharged from the cooling water outlet 42 to flow the cooling water into the water chamber body 4, and the heat generated by the discharge in the discharge gap 11 is converted into the ground electrode tube 1. Heat can be exhausted and cooled through. However, even in the discharge gap 11, the side close to the ground electrode tube 1 tends to be cooled, but the side close to the high voltage electrode tube 10 tends not to be cooled. Further, as in this example, when the high voltage electrode tube 10 is made of a dielectric, heat is generated due to dielectric loss, and the temperature of the dielectric itself rises. Further, due to the resistance of the metal film formed on the high voltage electrode tube 10, a slight amount of heat is generated even in the metal film. Thus, the side near the high voltage electrode tube 10 in the discharge gap 11 is likely to be hotter than the side near the ground electrode tube 1.

In general, it is widely known that ozone generation efficiency decreases as the temperature increases in ozone generation. As described above, ozone is generated through an extremely narrow discharge gap of 0.3 mm or less. If this extremely narrow discharge gap is non-uniform, the area where the gap is wide is not sufficiently cooled, the temperature of the gap space is increased, and the ozone generation efficiency is lowered. Does not go up. Therefore, the average ozone generation efficiency decreases as the gap variation increases. That is, the gap is preferably uniform both in the circumferential direction and in the flow direction. From this point of view, according to the first embodiment, there is no fear that the ground electrode tube 1 is bent, and the straight electrode is maintained in a straight state, so that a uniform gap is easily formed. There is an effect that an ozone generator with high generation efficiency can be obtained.

Next, the insulation distance will be described. As described above, an AC high voltage of, for example, several kV is applied to the high voltage electrode tube 10, and the oxygen side tube plate 2 and the oxygen header 5 are at ground potential. On the other hand, a metal film is formed on the inner surface of the high-voltage electrode tube 10 that becomes a high voltage when a high voltage is applied to almost the end. For this reason, about the distance A to the high-voltage electrode tube 10 and the oxygen header cylinder 5a wall shown in FIG. Further, regarding the distance B from the end of the high voltage electrode tube 10 to the oxygen side tube plate, an insulation distance of several centimeters or more is necessary in order to prevent discharge such as creeping discharge. Considering the case where a large number of ground electrode tubes 1 are arranged here, if there is a large gap between the ground electrode tube 1 disposed on the outermost periphery and the water chamber body 4, cooling water will slip through and cooling The effect is reduced. Accordingly, the distance between the outermost ground electrode tube 1 and the water chamber body 4 indicated by C in FIG. 3 needs to be equal to the distance between the ground electrode tubes 1, for example, about 1 cm. In FIG. 3, in order to avoid complication of the drawing, the ground electrode tubes 1 are shown by being thinned out, but actually, as described above, the interval between the ground electrode tubes 1 is, for example, 1 cm. It is densely arranged at the same pitch with a narrow interval.

At this time, in order to secure the insulation distance A in FIG. 3, the inner diameter of the oxygen header cylinder 5 a is larger than the inner diameter of the water chamber body 4. The tube header side flange 5c of the oxygen header may be an outer flange such as the ozone side, but it is preferable to use the tube plate side flange 5c of the oxygen header 5 as an inner flange as shown in FIGS. In this way, by using the tube plate side flange 5c of the oxygen header 5 as an inner flange, the diameter of the tube plate side flange 5c of the oxygen header 5 can be made smaller than the outer flange such as the ozone header 6, and the apparatus The overall size and weight can be reduced.

  In the present embodiment, for example, on the oxygen header side, the O-ring groove is provided in the oxygen side tube plate 2 and the tube plate side flange 5c of the oxygen header. For example, the grooves may be provided on the oxygen side tube sheet 2 side of the body flange 4 d and the oxygen header side of the oxygen side tube sheet 2. In this way, for example, when assembling with the ozone side down and the oxygen side up, the O-ring groove is opened upward, so the O-ring does not fall off simply by placing the O-ring. It is easy to assemble because there is no need to hold down.

Embodiment 2. FIG.
FIG. 4 is a cross-sectional view showing the structure of a can body that serves as a container of an ozone generator according to Embodiment 2 of the present invention. FIG. 5 is an enlarged cross-sectional view of a range indicated by a broken line D in FIG. 4, which is a main part of the ozone generator according to the second embodiment. 4 and 5, the same reference numerals as those in FIG. 1 denote the same or corresponding parts. The second embodiment of the present invention will be described below with reference to FIGS. As shown in the enlarged sectional view of FIG. 5, an O-ring groove 21 is formed in the oxygen side tube plate 2 around a hole through which the ground electrode tube 1 is passed. Reference numeral 22 denotes an O-ring having a diameter of about 25 mm, which seals between the ground electrode tube 1 and the oxygen tube plate 2. Reference numeral 23 denotes an O-ring holding plate for commonly holding the O-ring 22 attached to each of the plurality of ground electrode tubes 1, and is fixed to the oxygen side tube plate 2 by a plurality of bolts (not shown). . By doing so, the O-ring does not come off and has a structure that can sufficiently withstand the pressure of cooling water or oxygen gas. The other components are the same as those in FIG.

  Since the ozone generator of the second embodiment is configured as described above, the force applied from the oxygen side tube sheet 2 to the ground electrode tube 1 is further reduced as compared with the configuration of the first embodiment. Therefore, it is possible to reduce the possibility that the ground electrode tube 1 is bent and to obtain an ozone generator having a higher ozone generation efficiency. The effect of the inner flange of the tube sheet side flange 5c of the oxygen header 5 is the same as that of the first embodiment. Further, since the flatness of the oxygen side tube plate 2 is very high, it is not necessary to divide the O ring holding plate 23 in order to hold the O ring 22 of the ground electrode tubes 1 arranged in large numbers, and a single plate structure is sufficient. Function. Since one sheet is configured to press all the O-rings 22 of a large number of ground electrode tubes 1, manufacture and assembly are facilitated.

  FIG. 6 shows an assembly process of the main part of the can body having the structure of FIG. In FIG. 6, steps ST1 to ST5 are the same as steps ST1 to ST5 in FIG. In the second embodiment, the ground electrode tube 1 and the ozone side tube plate 3 are joined by expansion or welding (ST5), and then the O-ring 22 is connected from the end of the ground electrode tube 1 on the oxygen side tube plate 2 side. Then, the O-ring is pressed into the O-ring groove 21 formed in the oxygen-side tube plate 2 by the O-ring holding plate 23, and the space between the oxygen-side tube plate 2 and the ground electrode tube 1 is sealed (ST7). Thus, the main part of the can body to which the ground electrode tube 1 is attached is completed.

Embodiment 3 FIG.
FIG. 7 is a view showing an attachment structure of an oxygen header of an ozone generator according to Embodiment 3 of the present invention. FIG. 7 is a view of the tube header side flange 5c of the oxygen header as viewed from the ozone side tube plate 3, and each nozzle (gas and cooling water inlet / outlet, etc.) and various ozone side flange members are omitted for easy understanding. is doing. In FIG. 7, 52 is a tube plate fastening bolt, 53 is a header fastening bolt, and they are alternately arranged on the circumference. At the position of the tube sheet fastening bolt 52, nothing is applied to the tube sheet side flange 5 c of the oxygen header, and the oxygen side tube sheet 2 is threaded. Therefore, the tube sheet fastening bolt 52 fastens the oxygen tube plate 2 and the water chamber body flange 4b, and the tube header side flange 5c of the oxygen header is not fastened. On the other hand, at the position of the header fastening bolt 53, the oxygen tube plate 2 has a through hole slightly larger than the bolt diameter, and the oxygen header tube plate side flange 5c is threaded. Accordingly, the header fastening bolt 53 fastens the tube plate side flange 5c of the oxygen header and the water chamber body flange 4b via the oxygen side tube plate 2.

  With such a configuration, the oxygen side tube plate 2 is fastened to the water chamber body 4 by the tube plate fastening bolt 52, that is, the oxygen side tube plate 2, the water chamber body 4, the ozone is not included. A structure of the side tube sheet 3 and the ozone header 6 can be formed. As described above, in this state, both tube plates are assembled with high accuracy, and the ground electrode tube 1 is attached. At this time, the oxygen side tube plate 2 and the ground electrode tube 1 are attached by welding (Embodiment 1), O-ring (Embodiment 2), or other methods, but there is no oxygen header 5 so that the work can be performed. Is very easy to do. On the other hand, although there is work on the ozone side, there is no particular problem even if the ozone header 6 is attached because the length of the ozone header is short and does not get in the way.

  It should be noted that all the bolts are made the same as the above-described header fastening bolts, and the oxygen header 5 and the oxygen side tube sheet 2 are all attached to the body flange 4b of the water chamber body 4 without using the structure as in the present embodiment. In the case of the structure that is attached at the same time, there is a problem in workability because welding, O-ring insertion, or other work is performed while the oxygen header 5 is fixed. With this structure, if the oxygen header 5 is to be attached after welding or insertion of the O-ring, the oxygen side tube sheet 2 and the body flange 4b of the water chamber body must be removed once. At that time, the oxygen-side tube sheet 2 assembled with high accuracy is once loosened, and there is a possibility that displacement will occur and work will be increased.

  Therefore, by adopting a structure as shown in the third embodiment, it is possible to attach only the oxygen header 5 later without removing the oxygen-side tube sheet 2 assembled with high accuracy from the water chamber body flange 4b. There is an effect that an ozone generator having a very good workability can be obtained.

  In the present embodiment, the tube plate fastening bolts 52 and the header fastening bolts 53 are alternately arranged on the circumference, and the number is 1: 1. However, the number is not necessarily 1: 1. Not necessarily. For example, the number of tube sheet fastening bolts 52 may be reduced within a range in which strength and positional accuracy during assembly can be ensured.

Embodiment 4 FIG.
In the fourth embodiment, the effect of the ozone generator according to the present invention will be described. FIG. 8 shows the performance of the ozone generator when the dimensions of the discharge gap are different. The vertical axis indicates the maximum value of the ozone generation amount in each discharge gap dimension at 100%, and represents the performance of the ozone generator depending on how much the ozone generation amount varies with respect to this maximum value. This maximum value corresponds to the ozone generation amount obtained when the discharge gap length is uniform over the entire discharge tube.

  As already described, since the ground electrode tube is bent due to distortion during production, the discharge gap length cannot be made completely uniform. In particular, when the size of the discharge gap is 0.4 mm or less, the variation in the discharge gap length becomes large due to the manufacturing variation, and the degree of the performance variation of the ozone generator increases. The solid line in FIG. 8 indicates the performance variation of the ozone generator according to the configuration of the present invention, and the broken line indicates the performance variation of the ozone generator according to the conventional configuration. As can be seen from the above, in the case of the conventional configuration, when the size of the discharge gap becomes 0.3 mm or less, the variation in performance increases and the ozone generation efficiency as the whole apparatus decreases. Variations in performance can be kept small, and ozone generation efficiency as a whole device can be improved. Therefore, the effect of being able to supply a stable product with high ozone generation efficiency, in particular, with a discharge gap dimension of 0.3 mm or less, is significant by adopting the configuration of the present invention.

  Here, the dimension of the discharge gap is a design dimension, and is a dimension obtained from the difference between the inner diameter of the ground electrode tube and the outer diameter of the high-voltage electrode tube. That is, one half of the difference between the inner diameter of the ground electrode tube and the outer diameter of the high voltage electrode tube corresponds to the size of the discharge gap.

  In the first to fourth embodiments, the case where oxygen is used as the source gas has been described. However, the source gas may be air, which has the same effect of improving the ozone generation efficiency.

1: Ground electrode tube 2: Oxygen side tube plate 3: Ozone side tube plate 4: Water chamber body 4a: Water chamber body tube 4b, 4c: Body flange 5: Oxygen header 5a: Oxygen header tube 5b: Lid side flange 5c: Tube plate side flange 51: Raw material gas inlet 6: Ozone header 6a: Ozone header tube 6b: Lid side flange 6c: Tube plate side flange 61: Ozonized gas outlet 7: Oxygen header lid 8: Ozone header lid 9: AC High voltage power supply 10: High voltage electrode tube 11: Discharge gap 21: O ring groove 22: O ring 23: O ring holding plate 41: Cooling water inlet 42: Cooling water outlet 52: Tube plate fastening bolt 53: Header fastening bolt

Claims (11)

  A ground electrode tube, an oxygen side tube plate holding one end of the ground electrode tube, an ozone side tube plate holding the other end of the ground electrode tube, and cooling water around the ground electrode tube An ozone generator comprising: a water chamber body for forming a water chamber for circulating water; an oxygen header for supplying a source gas containing oxygen; and an ozone header for collecting the generated ozone gas. An ozone generator characterized by forming flanges on both sides of the body, bolting one of the flanges and the oxygen side tube sheet, and bolting the other flange and the ozone side tube sheet.   The ozone generator according to claim 1, wherein a flange is formed on the oxygen header, and the flange of the oxygen header, the oxygen side tube plate, and the flange of the water chamber body are bolted together.   The oxygen header and the water chamber trunk are cylindrical, and the flange of the oxygen header is an inner flange located inside the oxygen header, and the inner diameter of the oxygen header is larger than the inner diameter of the water chamber trunk The ozone generator according to claim 2 characterized by things.   Tube plate fastening bolts for fastening the flange formed on the water chamber body and the oxygen side tube plate, and the flange formed on the water chamber body via the oxygen side tube plate and the inner formed on the oxygen header The ozone generator according to claim 3, further comprising a header fastening bolt that fastens the flange.   The seal between the ground electrode tube and the ozone side tube plate is performed by expanding or welding, and the seal between the ground electrode tube and the oxygen side tube plate is performed by welding. Ozone generator.   5. The seal between the ground electrode tube and the ozone side tube plate is performed by expanding or welding, and the seal between the ground electrode tube and the oxygen side tube plate is performed by an O-ring. The ozone generator described in 1.   The ozone generator according to claim 6, further comprising an O-ring holding plate for commonly holding an O-ring attached to each of the plurality of ground electrode tubes.   In a discharge tube formed by inserting a high voltage electrode tube inside a ground electrode tube, the dimension of the discharge gap held between the inner surface of the ground electrode tube and the outer surface of the high voltage electrode tube is 0.3 mm or less The ozone generator according to any one of claims 1 to 7, characterized in that It is a manufacturing method of the ozone generator of Claim 1,
Inserting a ground electrode into the ozone side tube sheet;
Aligning the water chamber fuselage with the ozone side tube plate, and fastening the water chamber fuselage, the ozone side tube plate and the ozone header with a bolt;
Inserting the ground electrode tube into the oxygen side tube plate, and aligning the oxygen side tube plate and the water chamber body;
Connecting the oxygen side tube sheet and the water chamber body with a bolt;
A method for producing an ozone generator, comprising: Joining the ground electrode tube and the ozone side tube sheet by expanding or welding; and
The manufacturing method of the ozone generator of Claim 9 provided with the process of joining a ground electrode pipe | tube and an oxygen side tube sheet by welding. Joining the ground electrode tube and the ozone side tube sheet by expanding or welding; and
And a step of inserting an O-ring from an end of the ground electrode tube on the oxygen side tube plate side and pressing the O ring in an O ring groove formed in the oxygen side tube plate by an O ring press plate. The manufacturing method of the ozone generator of Claim 9.

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