JP3696093B2 - Ozone-containing gas underwater diffuser, ozone-containing gas underwater diffuser system, and operation method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to advanced water treatment performed in a water purification plant, a sewage wastewater treatment plant, and the like, and in particular, an ozone-containing gas underwater aeration device that diffuses ozone-containing gas into water, an ozone-containing gas underwater aeration system, and an operation thereof. Regarding the method.
[0002]
[Prior art]
As advanced water treatment performed at water purification plants, ozone treatment, biological activated carbon treatment, and the like have been performed.
[0003]
Among these, the ozone treatment is performed using an ozone-containing gas underwater aeration system as shown in FIG. 5 (a diagram showing the present invention). As shown in FIG. 5, the ozone-containing gas delivered from one or more ozone generators 1 is sent via a process operation end / process data measurement end 2 that adjusts and measures fluid conditions such as pressure and flow rate. The air pipe 3 flows down and is sent to one or more ozone-containing gas underwater diffusers 7 installed in one or more ozone contact tanks 4. Here, the ozone contact tank 4 has usually 1 to 3 stage tanks 6 divided by a partition 5, and each ozone-containing gas underwater diffuser 7 is located at the bottom of each stage tank 6. is set up.
[0004]
The ozone-containing gas underwater diffuser 7 has a header pipe 9 connected to the air supply pipe 3 as shown in FIGS. 6A and 6B (showing the present invention). 9, a plurality of diffusers 8 for diffusing ozone-containing gas into water are attached via joints 10 so as to extend substantially horizontally in water.
[0005]
FIG. 9 is a diagram showing a configuration of a conventional diffuser. As shown in FIG. 9, the diffuser 8 includes a hollow body 11 made of a ceramic breathable porous body, and stainless end members 14 and 15 that seal open portions located at both ends of the hollow body 11. And a tetrafluoroethylene resin packing 13 for sealing the hollow body 11 and the end members 14 and 15, and a stainless steel fixing member 16 for fixing the hollow body 11 and the end members 14 and 15. are doing. Here, the end member 15 is provided with a connection port 17, and the diffuser 8 and the header pipe 9 are connected via a joint 10 provided on the connection port 17 side (see FIG. 6 (a) (b)). The ozone-containing gas flows in from the connection port 17 through the header pipe 9 and the joint 10, passes through the gas passage 18, enters the hollow body 11 made of the air-permeable porous body, and passes through the wall portion. Aerated in the water.
[0006]
Here, the operation of the ozone-containing gas underwater diffuser 7 is stopped by installation work, repair work, operation stop, etc., and the flow of ozone-containing gas is stopped, or the fluid conditions such as the flow rate and pressure of the ozone-containing gas are normal. Even if a valve in the middle of the piping such as the air supply pipe 3 is closed if the operating fluid conditions are reduced below the operating fluid conditions, the ozone-containing gas from the diffuser 8 installed at the bottom of the step tank 6 of the ozone contact layer 4 Water will flow back to the internal piping of the underwater diffuser 7. This is because the ozone-containing gas is a compressive fluid and there is a water depth pressure in the stage tank 6. Usually, when the ozone-containing gas underwater diffuser 7 is returned from the non-operating state to the operating state, the fluid conditions such as the flow rate and pressure of the ozone-containing gas are returned to the normal operating fluid conditions, As the cue of the completion of the discharge of the backflow water, the normal operation was started.
[0007]
By the way, the ozone-containing gas delivered from the ozone generator 1 has a dew point of −50 to −60 ° C. and is dry. Therefore, conventionally, there is no corrosion of the ozone-containing gas (containing a small amount of nitrogen oxide) inside the stainless steel pipe or structure, and the diffuser 8 in the non-operating state as described above. It was thought that the reverse flow of water was also easily discharged, the water remaining on the inner wall surface of the diffuser 8 was volatilized with the passage of the ventilation time, and the progress of corrosion was not a problem. Instead, clogging due to oxide deposition on the outer wall surface of the diffuser 8 caused by contact of the oxidizing ozone-containing gas with water (containing the oxide) has been a concern.
[0008]
[Problems to be solved by the invention]
However, when the present inventors conducted a detailed investigation on the ozone-containing gas underwater diffuser 7 that has been experimentally operated for a long period of time, the progress of corrosion that was not expected was confirmed. Specifically, a brown-colored corrosion product adheres and accumulates on the lower surface side of the inner wall surface of the diffuser 8, and the stainless material such as the fixing material 16 and the end members 14, 15 is reduced in corrosion. The progress of corrosion was severe. When such corrosion progresses, structural destruction of the air diffuser 8 occurs, and air diffusion failure due to non-uniform air diffusion or uneven expansion of the bubble diameter occurs, leading to a final shutdown. .
[0009]
10 (a) and 10 (b) are views for explaining the underwater diffused state of the conventional diffuser 8 shown in FIG. 9, and FIG. 10 (a) is a diagram showing the appearance of the diffuser 8. 10 (b) is a diagram showing an assumed situation inside the diffuser 8 shown in FIG. 10 (a).
[0010]
As shown in FIGS. 10A and 10B, in the conventional diffuser 8, the bubbles 19 are generated only from the upper side of the hollow body 11, and the bubbles 19 are not generated from the lower side where the water depth pressure increases. For this reason, even when the operation of the ozone-containing gas underwater diffuser 7 is restored, it is expected that the residual water 20 remains on the lower surface side of the inner wall surface of the diffuser 8. This residual water 20 acts as a humidity replenishment source in the diffuser 8 and is considered to cause corrosion of a metal material such as a stainless material that does not cause a problem in a dry state. This residual water 20 is generated every time the ozone-containing gas underwater diffuser 7 is in a non-operating state, and is expected to always permeate in the form of osmotic water. The amount of the residual water 20 gradually evaporates and disappears due to the dry ozone-containing gas sent to the ozone-containing gas underwater diffuser 7 in the operating state, but this depends on the mode in the non-operating state. Will change.
[0011]
The present invention has been made on the basis of such knowledge, and by suppressing the progress of corrosion due to residual water caused by the structure of the ozone-containing gas underwater diffuser, etc., aeration failure, operation stoppage associated with this, etc. Ozone-containing gas underwater aeration device, ozone-containing gas underwater aeration system, and operation method thereof are provided that can stably generate long-term aeration of ozone-containing gas in water. For the purpose.
[0012]
[Means for Solving the Problems]
As a first solution, the present invention has a hollow body to which ozone-containing gas is supplied in an ozone-containing gas underwater diffuser that diffuses ozone-containing gas into water. Provided is an ozone-containing gas underwater diffuser characterized in that only the portion located on the lower side is air permeable.
[0013]
In the first solving means described above, the hollow body preferably has a non-breathable wall portion located on the upper side in water and a breathable wall portion located on the lower side. Moreover, it is preferable that a hollow body has a hollow air permeable porous body and the non-air permeable finishing layer provided in the part located in the upper part side in water among this air permeable porous body. Further, the hollow body has a non-breathable body and a breathable porous body provided in a portion of the non-breathable body located on the lower side in water and forming a hollow body with the non-breathable body. It is preferable.
[0014]
  As a second solution, the present invention provides a breathable hollow body to which ozone-containing gas is supplied in an ozone-containing gas underwater diffuser that diffuses ozone-containing gas into water.A cylindrical hollow body having an open portion at the endAnd the hollow bodySaidAn ozone-containing gas underwater dispersion comprising: an end member that seals an open portion; and a fixing member that fixes the hollow body and the end member, wherein the fixing member is disposed outside the hollow body. Qi device is provided.
[0015]
  As a third solution, the present invention provides a breathable hollow body to which ozone-containing gas is supplied in an ozone-containing gas underwater diffuser that diffuses ozone-containing gas into water.A cylindrical hollow body having an open portion at the endAnd the hollow bodySaidAn end member that seals the open portion; and a fixing member that fixes the hollow body and the end member. The fixing member is disposed inside the hollow body, and at least the surface of the fixing member is oxidation resistant. Provided is an ozone-containing gas underwater diffuser characterized by comprising a material.
[0016]
In the third solving means described above, it is preferable that the oxidation resistant material includes at least one material selected from the group including ceramic, tetrafluoroethylene resin, and vinyl chloride.
[0017]
As a fourth solution, the present invention relates to an ozone-containing gas underwater aeration system that diffuses ozone-containing gas into water. The ozone generator and the fluid conditions of the ozone-containing gas delivered from the ozone generator are as follows. A process operation end for adjusting, a plurality of ozone-containing gas underwater diffusers for aspirating the ozone-containing gas delivered from the ozone generator into the ozone contact tank, and a controller for controlling the process operation end. The controller is configured to discharge residual water from the ozone-containing gas underwater diffuser while sequentially switching among the ozone-containing gas underwater diffusers among the plurality of ozone-containing gas underwater diffusers. There is provided an ozone-containing gas underwater aeration system characterized by having water discharge means.
[0018]
In the fourth solution described above, the residual water discharge means is configured such that the fluid condition of the ozone-containing gas underwater diffuser that is the target of residual water discharge among the plurality of ozone-containing gas underwater diffusers is the fluid condition under normal operation. It is preferable to discharge the residual water from the ozone-containing gas underwater diffuser, which is the target for discharging the residual water, by controlling the process operation end so that the allowable value is equal to or greater than the maximum value. Further, the residual water discharge means is configured such that a fluid condition of an ozone-containing gas underwater diffuser other than the ozone-containing gas underwater diffuser that is the target of residual water discharge among the plurality of ozone-containing gas underwater diffusers is in a normal operation. It is preferable to discharge the residual water from the ozone-containing gas underwater diffuser, which is the target for discharging the residual water, by controlling the process operation end so that the allowable value in the minimum value direction of the fluid condition is reached. Furthermore, a process data measuring end for measuring process data relating to fluid conditions of the ozone-containing gas delivered from the ozone generator is further provided, and the residual water discharge means is configured to store residual water based on the process data measured by the process data measuring end. It is preferable to confirm whether or not it is possible to discharge.
[0019]
As a fifth solution, the present invention provides an ozone-containing gas underwater aeration system comprising a plurality of ozone-containing gas underwater aeration devices that diffuse ozone-containing gas delivered from an ozone generator into an ozone contact tank. In the operating method, the step of starting the residual water discharge operation periodically or at any time other than when returning from the non-operating state, and the residual water discharge target among the plurality of ozone-containing gas underwater diffusers. And a step of discharging residual water from the ozone-containing gas underwater diffuser while sequentially switching the ozone-containing gas underwater diffuser.
[0020]
In the fifth solving means described above, in the step of discharging the residual water, the fluid condition of the ozone-containing gas underwater diffuser that is the target for discharging the residual water among the plurality of ozone-containing gas underwater diffusers is the normal operation. It is preferable to discharge the residual water from the ozone-containing gas underwater diffuser, which is the target for discharging the residual water, by controlling the process operation end so that the allowable value is equal to or greater than the maximum value of the fluid conditions. Further, in the step of discharging the residual water, the fluid conditions of the ozone-containing gas underwater diffuser other than the ozone-containing gas underwater diffuser that is the target of residual water discharge among the plurality of ozone-containing gas underwater diffusers are usually It is preferable to discharge the residual water from the ozone-containing gas underwater diffuser that is the target for discharging the residual water by controlling the process operation end so that the allowable value in the minimum value direction of the operating fluid condition is reached. Furthermore, it is preferable to further include a step of confirming whether or not the residual water can be discharged based on the process data relating to the fluid condition of the ozone-containing gas before starting the residual water discharging operation.
[0021]
According to the first solving means of the present invention, only the portion of the hollow body located on the lower side in the water is air permeable, so that the air is diffused only on the lower side of the hollow body. For this reason, the discharge direction of the backflow water flowing into the hollow body in the non-operating state coincides with the ventilation direction, and the backflow water flowing into the hollow body in the non-operating state is discharged in a short time. There is no residual water remaining inside, and there is no penetration of permeated water into the hollow body. For this reason, the problem of corrosion of a fixing material or the like due to residual water as in the prior art can be greatly improved.
[0022]
According to the second solution of the present invention, since the fixing material is provided outside the hollow body, even when a stainless steel fixing material is used, the most damage is caused in the vicinity of the remaining water inside the hollow body. Corrosion of the existing fixing material can be easily avoided. For this reason, even if there is residual water inside the hollow body, the lifetime of the ozone-containing gas underwater diffuser can be greatly improved.
[0023]
According to the third solving means of the present invention, since the surface of the fixing member arranged inside the hollow body is made of an oxidation resistant material, it is located closest to the remaining water accumulated inside the hollow body. Therefore, corrosion of the most susceptible to corrosion can be avoided, and the life of the ozone-containing gas underwater diffuser can be greatly improved without changing the structure of the conventional ozone-containing gas underwater diffuser.
[0024]
According to the fourth and fifth solving means of the present invention, ozone that is a target for discharging residual water among a plurality of ozone-containing gas underwater diffusers periodically or at any time other than when returning from a non-operating state. Since the residual water is discharged from the ozone-containing gas underwater diffuser while sequentially switching the contained gas underwater diffuser, it is not sufficient to discharge only the backflow water that was used when returning from the non-operating state. The residual water remaining inside the contained gas underwater diffuser can be easily discharged. For this reason, the problem of corrosion of a fixing material or the like due to residual water as in the prior art can be greatly improved.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0026]
First embodiment
First, the ozone-containing gas underwater diffuser according to the first embodiment of the present invention will be described.
[0027]
The ozone-containing gas underwater aeration apparatus according to the first embodiment of the present invention is used in an ozone-containing gas underwater aeration system as shown in FIG.
[0028]
As shown in FIG. 5, the ozone-containing gas delivered from one or more ozone generators 1 passes through a process operation end / process data measurement end 2 that adjusts and measures at least one fluid condition of its pressure and flow rate. Then, it flows down the air supply pipe 3 and is sent to one or more ozone-containing gas underwater diffusers 7 installed in one or more ozone contact tanks 4. Here, the ozone contact tank 4 has usually 1 to 3 stage tanks 6 divided by a partition 5, and each ozone-containing gas underwater diffuser 7 is located at the bottom of each stage tank 6. is set up.
[0029]
6 (a) and 6 (b) are diagrams showing details of the ozone-containing gas underwater diffuser 7, and FIG. 6 (a) is a view of the ozone-containing gas underwater diffuser 7 as seen from the upper surface side of the step tank 6. FIG. 6B is a cross-sectional view taken along the line VIB-VIB in FIG.
[0030]
As shown in FIGS. 6 (a) and 6 (b), the ozone-containing gas underwater diffuser 7 has a header pipe 9 connected to the air supply pipe 3. The header pipe 9 contains ozone-containing gas in water. A plurality of diffusers 8 for aeration are attached via joints 10 so as to extend substantially horizontally in water.
[0031]
The diffuser 8 is generally attached to the side of the header tube 9 as shown in FIGS. 6 (a) and 6 (b). However, as shown in FIG. It may be attached via a joint 10. Thereby, many diffusers 8 can be accommodated in the limited installation area. Further, in this case, since the connection between the header pipe 9 and the diffuser 8 is performed directly below the header pipe 9 via the joint 10, the backflow water to the header pipe 9 is pushed out to the diffuser 8. The remaining water in the header pipe 9 is reduced, and corrosion in the header pipe 9 can be reduced.
[0032]
Next, the diffuser of the ozone-containing gas underwater diffuser according to the first embodiment of the present invention will be described with reference to FIGS. 1 (a), (b) and FIG. 1A is a longitudinal sectional view of the diffuser, and FIG. 1B is a view of the diffuser shown in FIG. 1A viewed from the IB direction. Moreover, FIG. 2 is a figure for demonstrating the underwater diffused state of the diffuser shown to FIG. 1 (a) (b).
[0033]
As shown in FIGS. 1 (a) and 1 (b), an air diffuser 8 diffuses ozone-containing gas into water, and includes a hollow body 11 to which ozone-containing gas is supplied, and the hollow body 11 End members 14 and 15 made of stainless steel for sealing the open portions located at both ends, a tetrafluoroethylene resin packing 13 for sealing the hollow body 11 and the end members 14 and 15, and the hollow body 11 A fixing member 16 made of stainless steel such as a bolt, a bolt nut, and a packing for fixing the end members 14 and 15 is provided. Here, the end member 15 is provided with a connection port 17, and the diffuser 8 and the header pipe 9 are connected via a joint 10 provided on the connection port 17 side (see FIG. 6 (a) (b)).
[0034]
Here, the hollow body 11 includes a hollow ceramic air-permeable porous body 12, and a non-air-permeable finishing layer 33 provided on a portion of the air-permeable porous body 12 located on the upper side in water. Only the portion of the hollow body 11 located on the lower side in water is air permeable. The non-breathable finishing layer 33 can be formed by attaching an upper drug or a pore blocking agent to the outer wall surface of the breathable porous body 12 and baking it.
[0035]
Next, the operation of the first embodiment of the present invention having such a configuration will be described.
[0036]
In the diffuser 8 of the ozone-containing gas underwater diffuser shown in FIGS. 1 (a) and 1 (b), the ozone-containing gas is connected via a header pipe 9 and a joint 10 (see FIGS. 6 (a) and (b)). It flows in from the port 17, passes through the gas passage 18, enters the hollow body 11, passes through the wall portion, and is diffused into the water.
[0037]
Here, the hollow body 11 is provided with a non-breathable finishing layer 33 in a portion of the breathable porous body 12 located on the upper side in water, and only a portion of the hollow body 11 located on the lower side in water. Since it is air permeable, as shown in FIG. 2, aeration to water is performed only on the lower side of the hollow body 11 (see bubbles 19 in FIG. 2).
[0038]
As described above, according to the first embodiment of the present invention, only the portion of the hollow body 11 located on the lower side in the water is air permeable, so that the air diffused into the lower portion of the hollow body 11 Done only on the side. For this reason, the discharge direction of the backflow water flowing into the hollow body 11 in the non-operating state coincides with the ventilation direction, and the backflow water flowing into the hollow body 11 in the non-operating state is discharged in a short time. There is no residual water remaining inside the body 11, and there is no penetration of permeated water into the hollow body 11. For this reason, the problem of corrosion of the fixing material 16 and the like due to residual water as in the prior art can be greatly improved.
[0039]
In the first embodiment described above, the non-breathable finishing layer 33 is provided in the portion of the breathable porous body 12 located on the upper side in water, so that the lower side of the hollow body 11 in water. However, the present invention is not limited to this, and the hollow body 11 has a non-breathable wall portion and a breathable wall portion located on the upper side and the lower side in water, respectively. Only the portion of the hollow body 11 located on the lower side in water may be air permeable. Specifically, it can be formed by integrally firing only a part of the wall portion of the hollow body 11 with the mixture of the porous forming material of the paste material before firing for forming the porous body.
[0040]
Further, in the first embodiment described above, the non-breathable finishing layer 33 is provided on the outer wall surface of the breathable porous body 12, but not limited thereto, the inner wall surface of the breathable porous body 12 and The non-breathable finishing layer 33 may be provided on both the inner wall surface and the outer wall surface of the breathable porous body 12.
[0041]
Second embodiment
Next, an ozone-containing gas underwater diffuser according to a second embodiment of the present invention will be described. Note that the ozone-containing gas underwater aeration apparatus according to the second embodiment of the present invention is used in an ozone-containing gas underwater aeration system as shown in FIG. 5 as in the first embodiment described above. Is.
[0042]
FIGS. 3 (a) and 3 (b) are views showing an air diffuser of an ozone-containing gas underwater diffuser according to the second embodiment of the present invention, and FIG. FIG. 3B is a cross-sectional view of the diffuser as viewed from the direction of IIIA in FIG.
[0043]
As shown in FIGS. 3 (a) and 3 (b), the diffuser 40 is for diffusing ozone-containing gas into water, and has a breathable hollow body 41 to which ozone-containing gas is supplied. ing.
[0044]
Here, the hollow body 41 is provided in a stainless non-breathable body 42 and a portion of the non-breathable body 42 that is positioned on the lower side in water, and forms the hollow body 41 together with the non-breathable body 42. A breathable porous body 43.
[0045]
Among these, the non-breathable body 42 can be formed by opening a circular hole in the lower part of a stainless steel pipe or the like and welding a pedestal 44 made of the same material to the hole. Here, in order to enhance the oxidation resistance, an oxidation resistant coating / lining such as a non-breathable ceramic or a tetrafluoroethylene resin may be provided inside the non-breathable body 42. The non-breathable body 42 may be formed by integral molding of a non-breathable ceramic, which is expensive but has excellent oxidation resistance.
[0046]
On the other hand, the air permeable porous body 43 is the same kind of material as the ceramic air permeable porous body 12 of the first embodiment described above, and has a flat plate shape. The breathable porous body 43 can be provided at a plurality of locations according to the installation status of the ozone-containing gas underwater diffuser 7 as shown in FIG.
[0047]
Here, the non-breathable body 42 and the breathable porous body 43 are made of stainless steel bolts in a positional relationship in which the non-breathable body 42 and the breathable porous body 43 are not easily corroded with the packing 45 sandwiched therebetween. The hollow body 41 is formed by being hermetically fixed.
[0048]
One of the open portions located at both ends of the hollow body 41 (non-breathable body 42) is sealed with a stainless steel end member (not shown) of the same type as the non-breathable body 42. Here, the air-impermeable body 42 and the end member are hermetically sealed with a stainless steel fixing material (not shown) such as a bolt, a bolt nut and a packing through a packing (not shown) made of tetrafluoroethylene resin. Fixed. The other open part of the hollow body 41 (non-breathable body 42) is connected to a header pipe connected to the ozone generator.
[0049]
Next, the operation of the second embodiment of the present invention having such a configuration will be described.
[0050]
In the diffuser 40 of the ozone-containing gas underwater diffuser shown in FIGS. 3 (a) and 3 (b), the ozone-containing gas enters the inside of the hollow body 41 from the other open portion via the header tube, and the wall portion thereof. It is diffused through the water.
[0051]
Here, the hollow body 41 includes a stainless steel non-breathable body 42 and a breathable porous body 43 provided in a portion of the non-breathable body 42 that is located on the lower side in water. Since only the portion (the lower side of the hollow body 41) provided with the air permeable porous body 43 is air permeable, the diffusion of air into the water is performed only on the lower side of the hollow body 41.
[0052]
As described above, according to the second embodiment of the present invention, only the portion where the air-permeable porous body 43 is provided (the lower side of the hollow body 41) is air-permeable. Is performed only on the lower side of the hollow body 41. For this reason, as in the first embodiment described above, the discharge direction of the backflow water flowing into the hollow body 41 in the non-operating state matches the ventilation direction, and flows into the hollow body 41 in the non-operating state. Backflow water is discharged in a short time, and there is no residual water remaining in the hollow body 41, and there is no penetration of permeated water into the hollow body 41. For this reason, the problem of corrosion of a fixing material or the like due to residual water as in the prior art can be greatly improved.
[0053]
In addition, according to the second embodiment of the present invention, since air is diffused into the water only from the flat air-permeable porous body 43 in the hollow body 41, the cylindrical air-permeable porous body Compared with the diffused air into the water from the curved surface having a vertical difference (water depth pressure difference) in the body, the location of the diffused air and the bubble diameter are made uniform, thereby improving the dissolution efficiency. This is because air diffusion becomes non-uniform, and if the bubble diameter increases with a partial increase in ventilation, the dissolution efficiency decreases. In addition, since the other open part of the hollow body 41 (non-breathable body 42) of the diffuser 40 is directly connected to the header pipe connected to the ozone generator, the diffuser is connected to the header pipe via a joint. Compared to the case of connecting in the state of holding, the leveling of the diffuser can be ensured without being caused by factors such as the degree of engagement with the joint, and the location of the diffuser and the bubble diameter can be made more uniform. it can.
[0054]
Furthermore, according to the second embodiment of the present invention, an inexpensive air-permeable porous body 43 can be made into a non-air-permeable body 42 that can be manufactured easily and accurately with a stainless steel pipe or plate. Since the hollow body 41 of the diffuser 40 is formed by attaching the diffuser 40, the diffuser 40 can be manufactured at low cost.
[0055]
Furthermore, according to the second embodiment of the present invention, any number of breathable porous bodies 43 can be attached to the non-breathable body 42 of the hollow body 41. It is also possible to fulfill the function of the header pipe 9 of the ozone-containing gas underwater diffuser 7 as shown in FIGS. 6 (a) and 6 (b), and at least one diffuser 40 shown in FIGS. By connecting more than this pipe, an inexpensive ozone-containing gas underwater diffuser can be realized.
[0056]
Third embodiment
Next, an ozone-containing gas underwater diffuser according to a third embodiment of the present invention will be described. Note that the ozone-containing gas underwater aeration apparatus according to the third embodiment of the present invention is used in an ozone-containing gas underwater aeration system as shown in FIG. 5 as in the first embodiment described above. Is. Moreover, it has the same structure as the ozone-containing gas underwater diffuser as shown in FIGS. 6 (a), 6 (b) and FIG.
[0057]
4 (a) and 4 (b) are views showing an air diffuser of an ozone-containing gas underwater diffuser according to a third embodiment of the present invention, and FIG. 4 (a) is a side view of the air diffuser. FIG.3 (b) is the figure which looked at the diffuser shown to Fig.3 (a) from the IVB direction.
[0058]
As shown in FIGS. 4 (a) and 4 (b), the diffuser 50 is for diffusing ozone-containing gas into water, and the air-permeable hollow body 11 to which ozone-containing gas is supplied, and this Stainless steel end members 52 and 53 that seal open portions located at both ends of the hollow body 11 are provided. The hollow body 11 is made of a ceramic breathable porous body.
[0059]
Here, the hollow body 11 and the end members 52 and 53 are hermetically fixed by a fixing material 51 made of stainless steel such as a bolt, a bolt nut and a packing through a packing (not shown) made of tetrafluoroethylene resin. Yes. Note that the fixing material 51 is disposed outside the hollow body 11. Further, the diameters of the end members 52 and 53 are made slightly larger than that of the hollow body 11 so that the fixing member 51 can clamp the hollow body 11 and the end members 52 and 53 outside the hollow body 11. In addition, the connection port 17 is provided in the end member 53, and the diffuser 8 and the header pipe | tube 9 are connected via the coupling 10 provided in this connection port 17 side (FIG. 6). (See (a) and (b)).
[0060]
As described above, according to the third embodiment of the present invention, since the fixing member 51 is provided outside the hollow body 11, even when a stainless steel fixing material is used, Corrosion of the most damaged fixing material in the immediate vicinity of the remaining water can be easily avoided. For this reason, even if there is residual water inside the hollow body 11, the lifetime of the ozone-containing gas underwater diffuser 7 can be significantly improved.
[0061]
Fourth embodiment
Next, an ozone-containing gas underwater diffuser according to a fourth embodiment of the present invention will be described. The ozone-containing gas underwater aeration apparatus according to the fourth embodiment of the present invention is used in an ozone-containing gas underwater aeration system as shown in FIG. 5 as in the first embodiment described above. Is. Moreover, it has the same structure as the ozone-containing gas underwater diffuser as shown in FIGS. 6 (a), 6 (b) and FIG.
[0062]
The diffuser of the ozone-containing gas underwater diffuser according to the fourth embodiment of the present invention has the same configuration as the conventional diffuser shown in FIG. That is, the diffuser includes a hollow body 11 made of a ceramic breathable porous body to which an ozone-containing gas is supplied, and a stainless end member 14 that seals open portions located at both ends of the hollow body 11. 15, a packing 13 made of tetrafluoroethylene resin for sealing the hollow body 11 and the end members 14, 15, and a fixing member 16 for fixing the hollow body 11 and the end members 14, 15. Yes.
[0063]
Here, the fixing member 16 is disposed inside the hollow body 11, but at least the surface thereof is non-ventilated containing at least one material selected from the group including ceramic, tetrafluoroethylene resin and vinyl chloride. It is made of highly oxidation-resistant material. The fixing material 16 may be made of such an oxidation-resistant material or a material obtained by coating such an oxidation-resistant material on another structural material.
[0064]
As described above, according to the fourth embodiment of the present invention, the fixing member 16 disposed inside the hollow body 11 is made of an oxidation-resistant material, or such an oxidation-resistant material is used as another structural material. Because it is coated, it is the part that is necessary to maintain the structure of the ozone-containing gas underwater diffuser, and the part that is most prone to corrosion and located closest to the remaining water inside the hollow body 11 Corrosion can be avoided, and the life of the ozone-containing gas underwater diffuser 7 can be greatly improved without changing the structure of the conventional ozone-containing gas underwater diffuser 7.
[0065]
Fifth embodiment
Next, an ozone-containing gas underwater aeration system and a method for operating the same according to a fifth embodiment of the present invention will be described.
[0066]
First, the overall configuration of the ozone-containing gas underwater aeration system will be described with reference to FIG.
[0067]
As shown in FIG. 5, the ozone-containing gas underwater aeration system is used to diffuse ozone-containing gas into the water, and includes a plurality of ozone generators 1 and the ozone generator 1 through an air supply pipe 3. The process operation end / process data measurement end 2 for adjusting and measuring the fluid condition of at least one of the pressure and flow rate of the ozone-containing gas sent out, and the ozone containing sent out from the ozone generator 1 through the air supply pipe 3 A plurality of ozone-containing gas underwater diffusers 7 that diffuse gas into the ozone contact tank 4 and a controller 70 that controls the process operation end / process data measurement end 2 are provided. As shown in FIG. 8, the process operation end / process data measurement end 2 includes a process operation end 2a for adjusting fluid conditions and a process data measurement end 2b for measuring process data related to fluid conditions. In FIG. 5, it is drawn as one block for convenience.
[0068]
Here, the ozone contact tank 4 has usually 1 to 3 stage tanks 6 divided by a partition 5, and each ozone-containing gas underwater diffuser 7 is located at the bottom of each stage tank 6. is set up.
[0069]
Moreover, the controller 70 discharges residual water from the ozone-containing gas underwater diffuser while sequentially switching among the ozone-containing gas underwater diffusers 7 among the ozone-containing gas underwater diffusers 7. Has residual water discharge means. In addition, the ozone-containing gas underwater diffuser 7 that is the target of discharge of residual water is a tank unit of the ozone contact tank 4, an in-stage division unit in each stage tank 6, or a tank classification when there are a plurality of ozone contact tanks 4. Selected in units.
[0070]
The process operation end 2a controlled by the controller 70 depends on the design specifications such as the scale of the ozone contact tank 4, the number of the step partitions 5, and the installation form of the ozone-containing gas underwater diffuser 7. Etc. in various forms. Specifically, the process operation end 2a may be provided in the air supply piping 3 for each block system in addition to providing the process operation end 2a in the air supply piping 3 for each system. The same applies to the process data measuring end 2b. In addition, in any embodiment, the process operation end 2a and the process data are within a range that does not hinder actual operation, with the ozone-containing gas underwater diffuser that is the target of discharge of residual water as a necessary minimum unit. It is desirable to reduce the number of measurement ends 2b as much as possible.
[0071]
FIG. 8 is a block diagram showing the details of the residual water discharge means of the controller 70.
[0072]
As shown in FIG. 8, the controller 70 includes an automatic timer 71, manual switches 72a and 72b, a residual water discharge command / release command unit 73, a prior confirmation operation unit 74, a residual water discharge switching operation unit 75, and a normal operation return operation. A portion 76 is provided.
[0073]
The controller 70 starts a residual water discharge operation in response to a start command from the automatic timer 71 or the manual switch 72a, and issues a residual water discharge command to the prior confirmation operation unit 74 via the residual water discharge command / release command unit 73. It has become. Here, the remaining water discharge command / cancellation command unit 73 receives the release command based on the manual switch 72b or the cancel command based on the abnormality determination by the prior confirmation operation unit 74 in addition to the start command, and collects the remaining water. The operation is started and released.
[0074]
The prior confirmation operation unit 74 confirms whether or not there is any problem in starting the residual water discharge operation. Specifically, prior to starting the residual water discharge operation, the prior confirmation operation unit 74 determines the normality of the process, that is, the process data such as the pressure and flow rate measured by the process data measurement end 2b is the fluid condition of the normal operation. It is confirmed whether or not the remaining water can be discharged. In addition, it is desirable to add the confirmation conditions based on the control change range intrinsic | native to the characteristics of the water treatment plant plant etc. by the process operation end 2a to the confirmation conditions here. Even if the process data such as pressure and flow rate measured by the process data measuring end 2b are within the range of the fluid conditions for normal operation, the remaining water is reduced due to deterioration of water quality, which is the most important matter for plant control. Since there are times when it is desired to avoid the disturbance being applied to the discharge control, it is desirable to add water quality as the process data measured by the process data measuring end 2b.
[0075]
When the prior confirmation operation unit 74 confirms the normality of the process, the process proceeds to the next residual water discharge switching operation unit 75. The residual water discharge switching operation unit 75 automates the operation of the process operation end 2a, switches the ozone-containing gas underwater diffuser to be the residual water discharge target from the normal operation control to the residual water discharge control, and keeps the remaining water for a predetermined time. Discharge. Specifically, the residual water discharge switching operation unit 75 is configured such that the fluid condition of the ozone-containing gas underwater diffuser that is the target of residual water discharge among the plurality of ozone-containing gas underwater diffusers 7 is the maximum of the fluid conditions during normal operation. Other ozone-containing gases other than the ozone-containing gas under-air diffuser that controls the process operation end 2a so that the allowable value is equal to or greater than the value, or among the plurality of ozone-containing gas under-air diffusers 7 By controlling the process operation end 2a so that the fluid condition of the underwater diffuser becomes the permissible value in the direction of the minimum value of the fluid condition of normal operation, the residual water is discharged from the ozone-containing gas underwater diffuser that is the target for discharging the residual water. Is discharged.
[0076]
After the processing in the residual water discharge switching operation unit 75 is completed, the process proceeds to the normal operation return operation unit 76, the process operation end 2a is returned to the normal operation control, and the residual water discharge control is ended.
[0077]
Next, the operation of the fifth embodiment of the present invention having such a configuration will be described.
[0078]
In the ozone-containing gas underwater aeration system shown in FIG. 5, the ozone-containing gas delivered from one or more ozone generators 1 adjusts and measures the fluid condition of at least one of its pressure and flow rate. The air supply pipe 3 flows down through the data measurement end 2 and is sent to one or more ozone-containing gas underwater diffusers 7 installed in one or more ozone contact tanks 4.
[0079]
Here, the controller 70 that controls the process operation end 2a of the process operation end / process data measurement end 2 is an aeration of ozone-containing gas underwater that is a target for discharging residual water among the plurality of ozone-containing gas underwater aeration devices 7. Residual water is discharged from the ozone-containing gas water diffuser while sequentially switching the devices.
[0080]
As shown in FIG. 8, in the controller 70, first, the remaining water discharging operation is started periodically or at any time other than when the operation is returned from the non-operating state by the start command from the automatic timer 71 or the manual switch 72a. Let As a result, a residual water discharge command is issued to the prior confirmation operation unit 74 via the residual water discharge command / release command unit 73.
[0081]
Next, whether or not the process data such as the pressure and the flow rate measured by the process data measuring end 2b is within the range of the normal operation fluid conditions before starting the residual water discharge operation by the prior confirmation operation unit 74. Check whether the residual water can be discharged.
[0082]
When the prior confirmation operation unit 74 confirms the normality of the process, the process proceeds to the next residual water discharge switching operation unit 75. The residual water discharge switching operation unit 75 automates the control of the process operation end 2a, switches the ozone-containing gas underwater diffuser to be the residual water discharge target from the normal operation control to the residual water discharge control, and keeps the remaining water for a predetermined time. Discharge.
[0083]
Specifically, the residual water discharge switching operation unit 75 discharges the residual water among the plurality of ozone-containing gas underwater diffusers 7 when the ozone generator 1 that is the supply source of the ozone-containing gas has a margin. The process operation end closest to the ozone-containing gas underwater diffuser that is the target for discharge of residual water so that the fluid condition of the target ozone-containing gas underwater diffuser becomes an allowable value that is equal to or greater than the maximum value of the fluid conditions during normal operation. The operating condition of 2a is raised to its allowable value, and the operating condition is returned to its original state after a lapse of a predetermined time to complete the residual water discharge. Is discharged. In this way, the ozone-containing gas can be discharged within the range that does not hinder actual operation by discharging the residual water from the ozone-containing gas underwater diffuser while sequentially switching the ozone-containing underwater diffuser to be discharged. It is possible to operate the underwater diffuser.
[0084]
In addition, the residual water discharge switching operation unit 75 is a target for discharging residual water among the plurality of ozone-containing gas under-air diffusers 7 when the ozone generator 1 that is the supply source of the ozone-containing gas has no allowance. Other ozone-containing gas underwater diffusers other than the ozone-containing gas underwater diffuser, so that the fluid conditions of the ozone-containing gas underwater diffuser become the permissible value in the direction of the minimum value of the fluid conditions during normal operation. Residual water from the ozone-containing gas underwater diffuser, which is the target for draining residual water, by reducing the operating conditions of some other process operation ends 2a corresponding to the gas apparatus to an allowable value in the direction of the minimum value of normal operation Is discharged. In addition, when there is a shortage in discharging the residual water from the ozone-containing gas underwater diffuser that is the target for discharging the residual water, it can be dealt with by increasing the number of process operation ends 2a that are the target of the operation. . Control of the process operation end 2a in such a range does not hinder the actual operation of the ozone-containing gas underwater diffuser. In addition, if the influence of the continuation of the discharge of the residual water cannot be ignored, it can be dealt with by limiting the number of discharges of the residual water performed in a day.
[0085]
Thereafter, after the processing in the residual water discharge switching operation unit 75 is completed, the process proceeds to the normal operation return operation unit 76, the process operation end 2a is returned to the normal operation control, and the residual water discharge control is ended.
[0086]
As described above, according to the fifth embodiment of the present invention, the remaining water discharge target among the plurality of ozone-containing gas underwater diffusers 7 is periodically or at any time other than when returning from the non-operating state. Since the residual water is discharged from the ozone-containing gas underwater diffuser while sequentially switching the ozone-containing gas underwater diffuser, it is not sufficient to discharge only the backflow water that was performed when returning from the non-operating state. The residual water remaining in the ozone-containing gas underwater diffuser 7 can be easily discharged. For this reason, the problem of corrosion of a fixing material or the like due to residual water as in the prior art can be greatly improved.
[0087]
Further, according to the fifth embodiment of the present invention, whether the process data such as pressure and flow rate measured by the process data measuring end 2b by the prior confirmation operation unit 74 is within the range of fluid conditions for normal operation. Checking whether the residual water can be discharged or not, so it is possible to discharge the residual water while checking the normality of the process data, and tolerate the influence of disturbance on the process data. Can be suppressed.
[0088]
Furthermore, according to the fifth embodiment of the present invention, the residual water discharge means is incorporated in the controller 70, and the discharge of the residual water is automatically performed based on preset conditions. The residual water remaining inside the underwater diffuser 7 can be discharged easily and reliably.
[0089]
In the fifth embodiment described above, the residual water discharging means is incorporated in the controller 70, but the present invention is not limited to this, and it may be provided separately from the controller 70.
[0090]
Further, in the fifth embodiment described above, the prior confirmation operation unit 74 is provided in the residual water discharge means. However, the prior confirmation operation unit 74 is omitted in a small-scale plant or a plant having a simple system configuration. It is also possible to do.
[0091]
【The invention's effect】
As described above, according to the present invention, by suppressing the progress of corrosion due to residual water due to the structure of the ozone-containing gas underwater diffuser, it is possible to prevent the occurrence of poor aeration and the accompanying shutdown. Thus, it is possible to stably diffuse the ozone-containing gas in water for a long period of time.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of an air diffuser of an ozone-containing gas underwater diffuser according to a first embodiment of the present invention.
FIG. 2 is a view for explaining an underwater diffused state of the diffuser shown in FIG. 1;
FIG. 3 is a diagram showing a configuration of an air diffuser of an ozone-containing gas underwater diffuser according to a second embodiment of the present invention.
FIG. 4 is a diagram showing a configuration of an air diffuser of an ozone-containing gas underwater diffuser according to a third embodiment of the present invention.
FIG. 5 is a system diagram showing an overall configuration of an ozone-containing gas underwater aeration system to which the present invention is applied.
FIG. 6 is a diagram showing details of the ozone-containing gas underwater diffuser shown in FIG.
7 is a view showing a modification of the ozone-containing gas underwater diffuser shown in FIG. 6. FIG.
FIG. 8 is a block diagram showing details of residual water discharge means in a controller of an ozone-containing gas underwater aeration system according to a fifth embodiment of the present invention.
FIG. 9 is a view showing a configuration of a diffuser of a conventional ozone-containing gas underwater diffuser.
FIG. 10 is a view for explaining an underwater diffused state of the diffuser shown in FIG. 9;
[Explanation of symbols]
1 Ozone generator
2 Process operation end / Process data measurement end
2a Process operation end
2b Process data measurement end
3 Air supply piping
4 Ozone contact tank
5-stage partition
6-stage tank
7 Ozone-containing gas underwater diffuser
8 Diffuser
9 Header pipe (pipe)
10 Fitting
11 Hollow body
12 Breathable porous body
13 Packing
14, 15 End member
16 Fixing material
17 Connection port
18 Gas passage
19 Bubble
20 Remaining water
33 Non-breathable finish
40 Diffuser
41 Hollow body
42 Non-breathable body
43 Breathable porous material
44 pedestal
45 Packing
50 Diffuser
51 Fixing material
52,53 End member
70 Controller
71 Automatic timer
72a, 72b Manual switch
73 Residual water discharge command / release command section
74 Prior confirmation operation part
75 Residual water discharge switching operation section
76 Normal operation return operation part

Claims (15)

In an ozone-containing gas underwater diffuser that diffuses ozone-containing gas into water,
An ozone-containing gas underwater diffuser comprising a hollow body to which an ozone-containing gas is supplied, wherein only a portion of the hollow body located on the lower side in water is air permeable.   The ozone-containing gas underwater diffuser according to claim 1, wherein the hollow body has a non-breathable wall portion located on the upper side in water and a breathable wall portion located on the lower side.   The hollow body includes a hollow air-permeable porous body and a non-air-permeable finishing layer provided in a portion of the air-permeable porous body located on the upper side in water. The ozone-containing gas underwater diffuser described.   The hollow body includes a non-breathable body and a breathable porous body provided in a portion of the non-breathable body that is located on the lower side in water and forms a hollow body together with the non-breathable body. The ozone-containing gas underwater diffuser according to claim 1. In an ozone-containing gas underwater diffuser that diffuses ozone-containing gas into water,
A breathable hollow body to which an ozone-containing gas is supplied , a cylindrical hollow body having an open portion at an end; and
And the end member for sealing the opening portion of the hollow body,
A fixing member for fixing the hollow body and the end member;
The ozone-containing gas underwater diffuser, wherein the fixing material is disposed outside the hollow body. In an ozone-containing gas underwater diffuser that diffuses ozone-containing gas into water,
A breathable hollow body to which an ozone-containing gas is supplied , a cylindrical hollow body having an open portion at an end; and
And the end member for sealing the opening portion of the hollow body,
A fixing member for fixing the hollow body and the end member;
The ozone-containing gas underwater diffuser characterized in that the fixing material is disposed inside the hollow body, and at least the surface of the fixing material is made of an oxidation resistant material. The ozone-containing gas water diffuser according to claim 6 , wherein the oxidation resistant material includes at least one material selected from the group including ceramic, tetrafluoroethylene resin, and vinyl chloride. In an ozone-containing gas underwater aeration system that diffuses ozone-containing gas into water,
An ozone generator,
A process operation end for adjusting fluid conditions of an ozone-containing gas delivered from the ozone generator;
A plurality of ozone-containing gas underwater diffusers that diffuse the ozone-containing gas delivered from the ozone generator into the ozone contact tank;
A controller for controlling the process operation end,
The controller is configured to discharge residual water from the ozone-containing gas underwater diffuser while sequentially switching the ozone-containing gas underwater diffuser to be discharged from the plurality of ozone-containing gas underwater diffusers. An ozone-containing gas water aeration system characterized by having a discharge means.   The residual water discharge means is configured such that the fluid condition of the ozone-containing gas underwater diffuser that is the target of residual water discharge among the plurality of ozone-containing gas underwater diffusers is an allowable value that is equal to or greater than the maximum value of the fluid conditions of normal operation. 9. The ozone-containing gas underwater aeration system according to claim 8, wherein residual water is discharged from an ozone-containing gas underwater aeration device to be subjected to residual water discharge by controlling a process operation end.   The residual water discharge means is a fluid condition in which the fluid condition of the ozone-containing gas underwater diffuser other than the ozone-containing gas underwater diffuser that is the target for discharging residual water is a normal operation fluid condition among a plurality of ozone-containing gas underwater diffusers. The residual water is discharged from the ozone-containing gas underwater diffuser that is the target for discharging the residual water by controlling the process operation end so as to be an allowable value in the minimum value direction. Contained gas underwater aeration system. A process data measuring end for measuring process data relating to fluid conditions of the ozone-containing gas delivered from the ozone generator;
9. The ozone-containing gas underwater aeration system according to claim 8, wherein the residual water discharging means confirms whether or not the residual water can be discharged based on the process data measured by the process data measuring end. . In the operation method of the ozone-containing gas underwater diffuser system comprising a plurality of ozone-containing gas underwater diffusers that diffuse the ozone-containing gas delivered from the ozone generator into the ozone contact tank,
A step of starting the residual water discharge operation periodically or at any time other than when returning from the non-operating state;
Discharging the residual water from the ozone-containing gas underwater diffuser while sequentially switching the ozone-containing gas underwater diffuser to be discharged from the plurality of ozone-containing gas underwater diffusers. Operation method of ozone-containing gas underwater aeration system.   In the step of discharging the residual water, the fluid condition of the ozone-containing gas underwater diffuser that is the target for discharging the residual water among the plurality of ozone-containing gas underwater diffusers becomes an allowable value that is equal to or greater than the maximum value of the fluid conditions of normal operation. 13. The method for operating an ozone-containing gas underwater aeration system according to claim 12, wherein the residual water is discharged from the ozone-containing gas underwater aeration device that is the target for discharging the residual water by controlling the process operation end as described above. .   In the step of discharging the residual water, the fluid conditions of the ozone-containing gas underwater diffuser other than the ozone-containing gas underwater diffuser to be discharged from the plurality of ozone-containing gas underwater diffusers are in normal operation. 13. Residual water is discharged from an ozone-containing gas underwater diffuser, which is a target for discharging residual water, by controlling a process operation end so as to be an allowable value in a minimum value direction of fluid conditions. Of operating an ozone-containing gas underwater aeration system.   13. The method according to claim 12, further comprising the step of confirming whether or not the residual water can be discharged based on the process data relating to the fluid condition of the ozone-containing gas before starting the residual water discharging operation. Operation method of ozone-containing gas underwater aeration system.

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