JPS644476Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention is based on a filler layer on which aerobic microorganisms are attached.
The present invention relates to a fixed bed catalytic oxidation tank in which treated water containing BOD components and gas containing oxygen are introduced and BOD components are removed through biological oxidation.

A fixed bed contact oxidation tank receives water to be treated containing BOD components from the upper or lower part of a filler layer made of gravel, crushed stone, Raschig rings, honeycomb tubes, reticulated bodies, etc., and contains oxygen from the lower part of the filler layer. BOD components in the water to be treated are biologically oxidized and removed by the action of aerobic microorganisms that have grown on the filler layer by flowing gas in an upward flow. It is easy to manage, and in recent years it has come to be widely used as a treatment device for organic wastewater. Note that air is generally used as the oxygen-containing gas used in the fixed bed catalytic oxidation tank, but in some cases, oxygen gas, etc., whose oxygen content has been increased by removing nitrogen, etc. from the air with an adsorbent, is used. used.

As shown in FIG. 1, a conventional fixed bed catalytic oxidation tank has a filling layer 2 formed in a circular or rectangular tank 1, and a large number of holes communicating with raw water pipes 3 in the lower part of the filling layer 2. Water sprinkler pipe 4 and air pipe 5
A large number of diffuser pipes 7 each having a large number of holes are buried therein and communicate with the blower 6 via the troughs 9 which communicate with the treated water pipe 8 in the upper part of the filler layer 2.
When treating water containing BOD components, the water to be treated flows in through the hole in the sprinkler pipe 4 via the raw water pipe 3, and the blower 6 is driven to blow air. Air flows in through the hole in the diffuser pipe 7 via the pipe 5. In this way, the BOD components in the water to be treated are biologically oxidized by the activity of the aerobic microorganisms that have grown on the filler layer 2, and the treated water from which the BOD components have been removed is obtained from the treated water pipe 8 via the trough 9. be able to.

However, if this device is operated for a long period of time, the water sprinkler pipe 4 or the aeration pipe 7 buried under the filler layer 2 may be damaged, or the holes thereof may become clogged. Or diffuser pipe 7
must be inspected, cleaned or replaced. At this time, all of the filler 10 in the filler layer 2 must be taken out of the tank 1, which requires a great deal of labor and time. Furthermore, by taking out the filler 10, the microbial film that has grown on the filler 10 is removed. It was destroyed, causing problems with operation when restarted. In addition, in order to eliminate the above-mentioned problems, as shown in Figure 2, the tank 1
A screen 11 supporting a filler layer 2 in the lower part of the
A diffuser pipe 7 is installed in the lower part of the screen 11 to communicate with the blower 6 via the air pipe 5, and a raw water pipe 3 is connected to the lower part of the screen 11 and to the side wall of the tank 1, and a manhole is installed. There is also a fixed bed contact oxidation tank that is equipped with a manhole 12 and enters the lower part of the screen 11 through the manhole 12 to inspect, clean, and replace the aeration pipe 7. When in use, the screen 11 receives a large load of 5,000 to 7,500 kg/m ² , so a large number of supporting members are required to support the screen 11, and the lower part of the screen 11 is extremely difficult to work with due to the supporting members and piping. Furthermore, there is a danger that the filler 10 may fall due to corrosion of the screen 11, which poses a safety problem for workers.

The present invention was developed in view of the above-mentioned drawbacks, and the purpose is to facilitate the inspection, cleaning, and replacement of the piping attached to the lower part of the packing material layer in a fixed bed catalytic oxidation tank. A filler with microorganisms attached to its surface is filled, and the filler layer is filled with
In a fixed bed catalytic oxidation tank in which treated water containing BOD components and gas containing oxygen are introduced and the BOD components are removed through biological oxidation, the packing material layer is supported and the gas containing oxygen can be circulated. A screen is supported by a number of support stands provided at intervals on the bottom of the oxidation tank, and an aeration pipe is provided in the space formed by the screen, the bottom plate, and the support, and the aeration pipe is connected to the oxidation tank. This invention relates to a fixed bed catalytic oxidation tank characterized in that it can be freely taken out from the side wall of the tank.

Hereinafter, the present invention will be explained in detail based on the drawings.

Figures 3 to 6 show an example in which the present invention is applied to an upward flow type fixed bed contact oxidation tank in which the water to be treated passes through the filling material layer in an upward flow. Figure 4 is an explanatory view of the A-A' vertical section in Figure 3,
FIG. 5 is a partially cutaway perspective explanatory view, and FIG. 6 is a vertical cross-sectional explanatory view showing an example of a support for the air diffuser 7.
A tank 1 having a trough 9 connected to a treated water pipe 8 at the top
A large number of elongated support stands 14 whose length spans the entire width of the tank 1 are installed at intervals on the bottom plate 13 of the tank 1, so as to cover the space 15 formed between the support stands 14 and the adjacent support stands 14. The screen 11 is installed using the support stand 14 as a support point, and the screen 1
On top of 1 is a support layer 16 several tens of centimeters high made of relatively coarse gravel or crushed stone, and on top of that is a support layer 16 usually made of gravel or crushed stone that is finer than that used for the support layer 16. A filler layer 2 with a height of 5 m is formed. All the spaces 15 are provided with a diffuser pipe 7 which communicates with the blower 6 via the air pipe 5 and which usually has a large number of holes in a staggered manner. Tank 1
The diffuser pipe 7 is fixed by bolts and nuts (not shown) to the embedded pipe 18 buried in the side wall of the
is attached to the outside of tank 1 so that it can be taken out freely. Further, a raw water pipe 3 communicating with the space 15 is provided at the lower part of the side wall of the tank 1. Here, as many support stands 14 as possible are provided, the number of spaces 15 is increased, and the center-to-center distance between the air diffuser 7 provided in the space 15 and the air diffuser 7 in the adjacent space 15 is shortened. Therefore, the part where air is not supplied to the filler layer 2 is eliminated, air is diffused efficiently, and the support base 1 adjacent to the support base 14 is
The support interval of the screen 11 provided between the screens 1 and 4 is also made small, which is advantageous for the strength of the screen 11. Generally, the distance between the centers of adjacent spaces 15 is 500 mm or less, and the width of the spaces 15 is 400 mm.
The above objective can be achieved by the following design. In order to uniformly disperse the air from the holes of the air diffuser 7 provided in the space 15 over the entire surface of the filler layer 2, it is desirable that the supports 14 be provided at equal intervals as much as possible. Further, it is advantageous in terms of construction that the support stand 14 is provided integrally with the bottom board 13.
Here, for the screen 11, in order to allow the air discharged from the holes of the air diffuser tube 7 to pass through without resistance, it is preferable to use a strong material such as a grid-like grating having a large porosity. The grating is made of iron or stainless steel for normal water to be treated, but for corrosive water to be treated, FRP or metal covered with plastic is used. Further, the support material layer 16 is provided to prevent the filler 10 from falling from the screen 11 when a small particle size material such as gravel or crushed stone is used for the upper filler 10. Gravel, crushed stone, or the like having a particle size larger than the filler 10 and larger than the opening of the screen 11 is used.

The treatment operation of the water to be treated in this apparatus is carried out as follows. When the water to be treated flows upwardly into the tank 1 from the raw water pipe 3, and the blower 6 is driven to flow air through the hole in the diffuser pipe 7 through the air pipe 5, the particles that have settled on the filler layer 2 are BOD components in the water to be treated are biologically oxidized by the activity of aerobic microorganisms, and treated water from which BOD components have been removed can be obtained from the treated water pipe 8 via the trough 9. If such treatment operations are continued, the filler layer 2 will become clogged due to enlargement of microorganisms, etc., so cleaning water and/or cleaning air is periodically introduced through the raw water pipe 3 or the aeration pipe 7 to fill the filling layer. Eliminate clogging of material layer 2. In addition, if the diffuser pipe 7 becomes damaged or clogged due to long-term operation of this device, the tank 1
The flange 1 is fixed to the embedded pipe 18 after draining the water inside.
7, and take out the air diffuser 7 from the space 15 to the outside of the tank 1 for inspection, cleaning, or replacement.
It is inserted into the space 15 again and the flange 17 is fixed to the embedded tube 18 with bolts and nuts (not shown). Since the air diffuser pipe 7 is installed in the space 15 and is not subjected to any special load, it is possible to use a synthetic resin pipe made of vinyl chloride or the like, which has good workability, is easy to handle, and has corrosion resistance. In addition, the diffuser pipe 7
By using flanges, coupling rings, etc., to connect the tubes at several points in the length direction so that they can be disassembled, when taking them out of the tank 1, if you take them out while disassembling them, you can reduce the amount of space required for taking them out. This is particularly effective when there are obstacles near the outside of the area. Furthermore, in order to facilitate the removal or insertion of the air diffuser 7, sliding feet 20 are attached to the air diffuser 7, reinforced with ribs 21, as shown in FIG. It is preferable to provide a support for the diffuser tube 7 so that it can be fitted onto the guide rail 22 and slid thereon.

Figures 7 to 9 show an example in which the present invention is applied to a downward flow type fixed bed contact oxidation tank in which water to be treated passes through a filling layer in a downward flow, and Figure 7 is a longitudinal cross-sectional view of the tank. Figure 8 is an explanatory view of the longitudinal section taken along line B-B' in Figure 7;
FIG. 9 is a partially cutaway perspective explanatory view. On the bottom plate 13 of the tank 1 having the raw water pipe 3' at the top, a large number of trapezoidal support stands 14 are regularly spaced at equal intervals both in the vertical and horizontal directions. The screen 11 is installed on the entire surface of the tank 1 on the support stand 14 using the support stand 14 and the side wall of the tank 1 as support points, and the support material layer 16 is placed on the top of the screen 11, and the filler layer is further placed on the top of the screen 11. Form layer 2. Also screen 11
A space 15 formed by the bottom plate 13 and the support base 14
A diffuser pipe 7 having a large number of holes that communicates with the blower 6 via the air pipe 5 is attached to the tank 1 so that it can be freely taken out from the tank 1 via the flange 17 and the embedded pipe 18, and communicates with the space 15. A treated water pipe 8' is provided at the lower part of the side wall of the tank 1.

The treatment operation of the water to be treated in this apparatus is carried out as follows. When the water to be treated flows downward from the raw water pipe 3' and the blower 6 is driven to flow air from the hole in the aeration pipe 7 through the air pipe 5, aerobic microorganisms that have settled on the filler layer 2 are removed. BOD components in the water to be treated are biologically oxidized by the activity, and treated water from which BOD components have been removed can be obtained from the treated water pipe 8'. If the air diffuser pipe 7 becomes damaged or clogged due to long-term operation of this device, remove the air diffuser pipe 7 from the tank 1 and inspect, clean, or replace it, as in the case of the upflow type fixed bed contact oxidation tank described above. Insert it into the space 15 again.

Here, as shown in FIGS. 7 and 9, the side surface of the support base 14 is sloped to improve the diffusion of the air flowing into the tank 1 from the hole of the air diffuser 7, so that the air flows into the filler layer 2. It is best to ensure that it is evenly supplied over the entire surface. In addition, in FIGS. 3 to 9, the air pipe 5
Although an example is shown in which only the aeration pipe 7 that communicates with the raw water pipe 3 is installed in the space 15, in order to improve the sprinkling of the water to be treated or the collection of the treated water, it is necessary to install the aeration pipe 7 that communicates with the raw water pipe 3 or the treated water pipe. The water collection pipe connected to 8'
It may be installed in the space 15 so as to be freely removable from the side wall of the tank 1, similarly to the aeration pipe 7.

As explained above, according to the fixed bed catalytic oxidation tank of the present invention, the piping attached to the lower part of the filler layer can be easily and safely inspected without taking out the filler or entering the fixed bed catalytic oxidation tank. , cleaning, and replacement.

[Brief explanation of the drawing]

Figures 1 and 2 are longitudinal sectional explanatory views of a conventional fixed bed catalytic oxidation tank, Figures 3 to 9 each show an embodiment of the device of the present invention, and Figures 3 to 6 are This is an example of an upflow type fixed bed contact oxidation tank, and the third
The figure is an explanatory longitudinal cross-sectional view, Fig. 4 is an explanatory longitudinal cross-sectional view taken along line A-A' in Fig. 3, and Fig. 5 is a partially cutaway explanatory perspective view.
FIG. 6 is an explanatory longitudinal cross-sectional view showing an example of a support for an aeration pipe, and FIGS. 7 to 9 are examples of a downflow type fixed bed catalytic oxidation tank. 8 is an explanatory longitudinal cross-sectional view taken along line B-B' in FIG. 7, and FIG. 9 is a partially cutaway perspective explanatory view. 1... Tank, 2... Filler layer, 3, 3'... Raw water pipe, 4... Water pipe, 5... Air pipe, 6... Blower, 7... Diffusion pipe, 8, 8'... Processed water pipe, 9...
...trough, 10...filling material, 11...screen, 12...manhole, 13...bottom plate, 14...
...Support stand, 15...Space part, 16...Support material layer,
17...Flange, 18...Embedded pipe, 19...Support material, 20...Sliding foot, 21...Rib, 22...
guide rail.

Claims (1)

[Scope of utility model registration request] A filler with aerobic microorganisms grown on its surface is filled, and treated water containing BOD components and gas containing oxygen are introduced into the filler layer to remove BOD components through biological oxidation. In a fixed bed catalytic oxidation tank, a screen that supports the filler layer and allows the flow of oxygen-containing gas is supported by a number of supports provided at intervals on the bottom plate of the oxidation tank, and the screen and the bottom plate are A fixed bed contact oxidation tank characterized in that an air diffuser is provided in a space formed by a support and a support, and the air diffuser can be freely taken out from a side wall of the oxidation tank.