JP2011218265A - Air diffuser - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly rinse each of air diffusing parts by supplying blow water in an air diffuser having a plurality of air diffusing parts.SOLUTION: The air diffuser is provided with a blow water-supplying implement 4 for supplying blow water to an air supply piping 1 having a plurality of air diffusing parts 2, and each air diffusing part 2 has a suction nozzle pipe 20 and an air diffusing plate 21 connected to the upper end of the nozzle pipe 20. The partition plates 5 for banking up the blow water by partitioning the lower area of a pipe inner cross-section in a pipe diameter direction are installed at a plurality of positions leaving space in the longitudinal direction within the air supply piping 1, and the spaces 6 partitioned by the plates 5 for banking up and holding the blow water are provided each air diffusing part 2. Since the blow water banked up and held in the spaces 6 is supplied to the nozzle pipe 20 of each air diffusing part 2, a definite amount of the blow water can be supplied to each air diffusing part 2 regardless of a clogging degree of the air diffusing plate of each diffusing part 2.

Description

  The present invention relates to an air diffuser provided in an aeration tank or the like of a sewage treatment facility.

  In a sewage treatment facility, an activated sludge method using decomposition / adsorption action by microorganisms is used to remove nitrogen compounds and carbon compounds in sewage. In order for the microorganisms in the activated sludge to be active, it is necessary to give oxygen to the microorganisms. For this reason, an aeration device is installed in the aeration tank of the sewage treatment facility, and air (oxygen) is put into the water from this aeration device. Supplied.

  This air diffuser has an air diffuser plate in which a large number of fine ventilation holes are formed, and air (fine bubbles) is discharged into the water through this air diffuser plate. There is a problem that the dirt component adheres to the diffuser plate and the vent hole is clogged. Most of the soil components that cause such clogging are slime formed by microorganisms. However, the slime has strong adhesion and cannot be easily removed or removed even if the air pressure is increased.

  In order to prevent clogging of the diffuser plate as described above, Patent Documents 1 and 2 disclose a diffuser device that can supply blow water into the device to periodically clean the diffuser plate. It is shown. The air diffuser includes an air supply pipe for air diffusion, a plurality of air diffusers provided at intervals in the longitudinal direction of the air supply pipe, and an air supply for supplying air for air diffusion to the air supply pipe And blow water supply means for supplying blow water to the air supply pipe, and each air diffuser penetrates the upper pipe wall of the air supply pipe, the lower end is located in the air supply pipe, and the upper end is the air supply A suction nozzle pipe located outside the pipe and a diffuser plate connected to the upper end of the suction nozzle pipe. In such an air diffuser, the blow water is periodically supplied from the blow water supply means into the air supply pipe, and the blow water is sucked into the suction nozzle pipe of each air diffuser and discharged from the air diffuser plate. The diffuser plate is washed.

  Further, the air diffuser shown in Patent Document 2 further includes high-pressure air supply means for supplying air having a pressure higher than air for air diffusion to the air supply pipe, and this high-pressure air supply means when supplying blow water. The high-pressure air is supplied to the air supply pipe and the blow water is pushed out from the diffuser plate with this high-pressure air, so that the cleaning effect is further enhanced.

JP 2009-172570 A JP 2009-172583 A

  However, the air diffuser disclosed in Patent Documents 1 and 2 has the following problems. That is, in the air diffuser having a plurality of air diffusers spaced apart in the longitudinal direction of the air supply pipe, the degree of clogging is different for each air diffuser, and therefore when blow water is supplied into the air supply pipe Alternatively, when a pressure is applied to the blow water with high-pressure air, a difference occurs in the amount of blow water sucked up from the suction nozzle tube by the air diffuser. That is, since the blown water is less likely to pass through the diffuser plate with more clogging, the amount of blown water sucked up from the suction nozzle tube is reduced. As a result, the diffuser plate cannot be sufficiently cleaned, and a vicious cycle occurs in which clogging is more likely to proceed.

  Accordingly, an object of the present invention is to appropriately clean the air diffuser plate of each air diffuser by supplying blow water in an air diffuser having a plurality of air diffusers spaced in the longitudinal direction of the air supply pipe. An object of the present invention is to provide an air diffuser that can be used.

The gist of the present invention for solving the above problems is as follows.
[1] An air supply pipe (1) for air diffusion, a plurality of air diffusers (2) provided at intervals in the longitudinal direction of the air supply pipe (1), and the air supply pipe (1) An air supply means (3) for supplying air for air diffusion and a blow water supply means (4) for supplying blow water to the air supply pipe (1) are provided. A suction nozzle pipe (20) penetrating the upper pipe wall of the air pipe (1) and having a lower end located in the air supply pipe (1) and an upper end located outside the air supply pipe (1), and the suction nozzle pipe In the air diffuser having the air diffuser plate (21) connected to the upper end of (20),
A partition plate (5) for damming blow water by partitioning the lower area of the pipe internal cross section in the pipe radial direction at a plurality of positions spaced in the longitudinal direction in the air supply pipe (1). A space (6) for holding the blow water dam that is partitioned by the partition plate (5) is provided for each air diffuser (2), and the suction nozzle pipe (20 A diffuser characterized by positioning the lower end of the
[2] The air diffuser according to [1], further comprising high-pressure air supply means (7) for supplying air higher than air for air diffusion to the air supply pipe (1). Qi device.

  In the air diffuser of the present invention, a space (6) for holding a blow water dam that is partitioned by a partition plate (5) is provided for each air diffuser (2), and the dam is formed by the space (6). Stopped and held blow water is supplied to the suction nozzle pipe (20) of each air diffuser (2), so that each air diffuser (2) is not affected by the degree of clogging of the air diffuser plate. A certain amount of blow water can be supplied to the gas part (2). Thereby, the diffuser plate which has been clogged can be sufficiently cleaned.

Whole explanatory drawing which shows typically one Embodiment of the aeration apparatus of this invention 1 is a partially cutaway side view partially showing one air diffuser in the embodiment of FIG. In the embodiment of FIG. 1, an explanatory view schematically showing a partition plate and a space for holding a blow water dam that is partitioned by the partition plate in a state in which a supply pipe is longitudinally sectioned. In the embodiment of FIG. 1, a perspective explanatory view schematically showing a partition plate and a space portion for holding a blow water dam that is partitioned by the partition plate Whole explanatory drawing which shows typically other embodiment of the diffuser of this invention

1 to 4 show an embodiment of an air diffuser according to the present invention. FIG. 1 is an overall explanatory view, and FIG. 2 is a partially cutaway side view partially showing one air diffuser. 3 is an explanatory view schematically showing a partition plate and a space for holding a blow water dam that is partitioned by the partition plate in a state where the air supply pipe is longitudinally sectioned, and FIG. 4 is a perspective explanatory view.
The basic configuration of the air diffuser shown in FIG. 1 and FIG. 2 is the same as that of the device shown in Patent Document 1, where 1 is an air supply pipe for air diffusion and 2 is an interval in the longitudinal direction of the air supply pipe 1. A plurality of air diffusers, 3 is an air supply means for supplying air for air supply to the air supply pipe 1, and 4 is a blow water supply means for supplying blow water to the air supply pipe 1. Moreover, x is an aeration tank (reaction tank by an activated sludge method) of a sewage treatment facility where a diffuser is installed.

Each air diffuser 2 penetrates the upper pipe wall of the air supply pipe 1, the suction nozzle pipe 20 having a lower end located in the air supply pipe 1 and an upper end located above the air supply pipe 1, and this suction A diffuser plate 21 connected to the upper end of the nozzle tube 20 is provided.
The reason why each of the air diffusers 2 is provided with the suction nozzle pipe 20 is that the blow water can be supplied to the air diffuser plate 21 without filling the air supply pipe 1 with water. When the air supply pipe 1 is filled with water, blow water tends to remain in the air supply pipe and the pipe line becomes thin, which may cause a problem in air diffusion.

The diffuser plate 21 is a plate-like body having a hollow inside, and the upper surface portion from which air is released is usually composed of a thin metal plate in which many fine air holes and slits are formed. Or something like that.
The suction nozzle pipe 20 has a lower end located in the vicinity of the inner bottom of the air supply pipe 1 so that the blow water can be sucked up even if the level of the blow water in the air supply pipe 1 is low. Generally, the height of the lower end of the suction nozzle pipe 20 from the inner bottom of the air supply pipe 1 is about 0 to 10 mm. The lower end surface 200 of the suction nozzle pipe 20 is formed in an inclined shape so that the blow water can be easily taken into the pipe, and the suction nozzle pipe 20 has the inclined lower end face 200 facing the upstream side in the blow water flow direction. The air supply pipe 1 is fixed. The inclination angle θ with respect to the vertical direction of the lower end surface 200 is 10 to 85 °, preferably about 30 to 80 °.
The diffuser plate 21 is connected to the upper end of the suction nozzle tube 20 so that the inside of both is in communication.

Further, a vent hole 8 is provided through the pipe wall (upper pipe wall) of the suction nozzle pipe 20 located in the air supply pipe 1. When the blow water is supplied, if the level of the blow water in the air supply pipe 1 is between the upper end and the lower end of the lower end surface 200, air for aeration is taken into the suction nozzle pipe 20 together with the blow water. Therefore, the air / water mixed phase is blown at a high blow speed. However, when the water level of the blow water becomes higher than the upper end of the lower end surface 200, only the blow water is sucked up by the nozzle tube 20, so that the air is mixed. The water extrusion blow has a relatively low blow speed. On the other hand, by providing the vent hole 8, air enters from the vent hole 8 even when the level of blow water is higher than the upper end of the lower end surface 200. It can be.
The air supply means is composed of, for example, a blower or the like, and supplies air for air diffusion to the air supply pipe 1.
The blow water supply means 4 includes, for example, a water storage tank and a water pump, and supplies blow water to the air supply pipe 1 through the blow water supply pipe 9.

In the basic structure of the air diffuser as described above, as shown in FIG. 3 and FIG. 4, the lower part of the pipe internal cross section in the pipe radial direction is provided at a plurality of positions spaced in the longitudinal direction in the air supply pipe 1. A partition plate 5 is installed to block the blow water by partitioning the region. The partition plate 5 of the present embodiment is configured in a substantially semicircular shape. The partition plate 5 is provided so as to sandwich each air diffuser 2 in the longitudinal direction of the air supply pipe 1, whereby the space portion 6 for holding the blow water dam that is partitioned by the partition plate 5 is provided for each air diffuser. Provided for each part 2. And the lower end of the said suction nozzle pipe | tube 20 is located in this space part 6. FIG.
Although the partition plate 5 should just have the height which partitions off the lower area | region of the pipe internal cross section in the pipe diameter direction of the air supply piping 1, generally the height of about 30 to 50% of the internal diameter of the air supply piping 1 It is preferable to have.

In such an air diffuser of the present invention, during normal operation, air for air diffusion is supplied from the air supply means 3 to the air supply pipe 1, and this air is diffused through the suction nozzle pipe 20 in each air diffuser 2. Released from the air plate 21 into the water. During continuous operation of such an air diffuser, blow water is supplied to the air supply pipe 1 from the blow water supply means 4 periodically (for example, every several hours to several days). This blow water is sucked up by the suction nozzle tube 20 in each air diffuser 2 (usually sucked up together with air for air diffuser) and cleans the air diffuser plate 21. In the air diffuser of the present invention, the partition plate 5 is provided for each air diffuser 2, and the blow water retained by the space 6 is sucked into the suction nozzle pipe 20 of each air diffuser 2. Since the air is sucked up, a certain amount of blow water can be supplied to each air diffuser 2 regardless of the degree of clogging of the air diffuser plate 21 of each air diffuser 2. That is, it is possible to prevent a large amount of blow water from being sucked into the diffuser plate 21 with a small degree of clogging, and to ensure a constant amount of blow water supply for each air diffuser 2. The diffuser plate 21 that has become clogged can be sufficiently cleaned.
In addition, as blow water, you may use the water which added the disinfectant for disinfecting a diffuser board other than pure water.

FIG. 5 is an overall explanatory view showing another embodiment of the air diffusing device of the present invention. The basic structure of this air diffuser is the same as that shown in Patent Document 2, and in addition to the structure shown in FIG. 1 and FIG. 2, the air supply pipe 1 is supplied with air having a pressure higher than that for air diffused. High-pressure air supply means 7 is provided.
The high-pressure air supply means 7 includes, for example, an air compressor and an air tank that stores compressed air discharged from the air compressor, and supplies the high-pressure air to the air supply pipe 1 through the high-pressure air supply pipe 10. In the other drawings, 11 is a check valve provided in the air supply pipe 1, 12 is an open / close valve, 13 is an open / close valve provided in the blow water supply pipe 9, and 14 is an open / close valve provided in the high-pressure air supply pipe 10. .

  In this air diffuser, during normal operation, the on-off valve 12 is opened, the on-off valves 13 and 14 are closed, and air for aeration is supplied from the air supply means 3 to the air supply pipe 1. Aeration is performed from 2. When the blow water is periodically supplied from the blow water supply means 4 to the air supply pipe 1 and the air diffuser plate of each air diffuser 2 is cleaned, the open / close valve 13 is opened and the blow water is supplied to the air supply pipe. 1 is supplied. When a sufficient amount of blow water is supplied into the air supply pipe 1, the on-off valve 14 is opened to supply high-pressure air to the air supply pipe 1, and the high-pressure air sucks up the blow water and passes through the nozzle pipe 20. Push out from the diffuser plate 21. Thereby, a higher cleaning effect than that of the air diffuser of FIGS. 1 and 2 can be obtained. The high-pressure air supplied to the air supply pipe 1 is prevented from escaping upstream (the air supply means 3 side) by the check valve 11.

  Also in such an air diffuser, a space 6 (not shown) for holding a blow water dam that is partitioned by a partition plate 5 (not shown) is provided for each air diffuser 2, and this space 6 is supplied to the suction nozzle tube 20 of each air diffuser 2, so that each air diffuser 2 is not affected by the degree of clogging of the air diffuser plate 21 of each air diffuser 2. A certain amount of blow water can be supplied. As a result, the diffuser plate 21 having become clogged can be sufficiently cleaned.

DESCRIPTION OF SYMBOLS 1 Air supply piping 2 Air diffusion part 3 Air supply means 4 Blow water supply means 5 Partition plate 6 Space part 7 High pressure air supply means 8 Ventilation hole 9 Blow water supply pipe 10 High pressure air supply pipe 11 Check valves 12, 13, 14 On-off valve 20 Suction nozzle tube 21 Diffuser plate 200 Lower end surface x Aeration tank

Claims (2)

Air supply pipe (1) for air diffusion, a plurality of air diffusers (2) provided at intervals in the longitudinal direction of the air supply pipe (1), and air supply pipe (1) Air supply means (3) for supplying the air and blow water supply means (4) for supplying blow water to the air supply pipe (1), and each of the air diffusers (2) is provided with an air supply pipe ( A suction nozzle pipe (20) passing through the upper pipe wall of 1) and having a lower end located in the air supply pipe (1) and an upper end located outside the air supply pipe (1), and the suction nozzle pipe (20) In the air diffuser having the air diffuser (21) connected to the upper end of
A partition plate (5) for damming blow water by partitioning the lower area of the pipe internal cross section in the pipe radial direction at a plurality of positions spaced in the longitudinal direction in the air supply pipe (1). A space (6) for holding the blow water dam that is partitioned by the partition plate (5) is provided for each air diffuser (2), and the suction nozzle pipe (20 A diffuser characterized by positioning the lower end of the   The air diffuser according to claim 1, further comprising high-pressure air supply means (7) for supplying air higher in pressure than air for air diffusion to the air supply pipe (1).

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