JPS5832634B2 - Wastewater oxidation treatment equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an oxidation treatment apparatus for organic matter-containing wastewater using a vertical tube bundle.

Conventional microbial oxidation treatment methods for wastewater containing organic matter, such as factory wastewater, involve placing a catalytic oxidation layer formed by a bundle of vertical pipes arranged in parallel to form a large number of square or hexagonal pipes in a treatment tank. A known method is to purify the wastewater by passing the wastewater, which has been submerged in water and has dissolved oxygen, through a vertical pipe bundle with a large surface area, and the microorganisms attached to the inner walls of the pipes aerobically oxidize and decompose pollutants. ing.

As shown in FIG. 1, an example of a general device for carrying out the above method is to install aeration pipes 2 at intervals near the bottom of the tank 1 in a substantially rectangular parallelepiped tank 1 and near the side walls in the long side direction. A vertical pipe bundle 3 is arranged avoiding the upper part of the tank 2, and an untreated water outlet 4 is placed on one side near both ends in the long side direction of the tank, and a treated water outlet 5 is placed on the other side.
This is provided.

In addition, as another known example, as shown in FIG. 2, a diffuser pipe 2 is provided near the center bottom of a substantially cubic tank 1, and a vertical tube bundle 3 is installed over substantially the entire area above the diffuser pipe 2. A central passage 3' is provided vertically in the center of the vertical tube bundle and corresponds to the diffuser pipe 2, and an untreated water outlet 4 and a treated water outlet 5 are provided diagonally when viewed from the top.

With such a device, while the organic matter-containing wastewater supplied from the population 4 to the tank 1 remains in the tank, the air supplied through the aeration pipe 2 mixes with the wastewater, resulting in a state in which oxygen is dissolved. At the same time, the air bubbles generated from the air diffuser 2 cause the air diffuser 2 to
A circulating flow is generated that rises from the vicinity and then descends through the vertical tube bundle 3 to which microorganisms are attached, and while the wastewater passes through the vertical tube bundle 3, the organic matter is oxidized by the microorganisms.

However, in this device, the diameter of the pipe is made small in order to increase the contact area between the microorganisms attached to the vertical pipe bundle 3 and the wastewater, and the water flow direction through the pipe is unidirectional. Since the flow is only downward, the upper surface of the vertical pipe bundle 3 is easily clogged with debris, scum, etc., which can easily block the pipe. Especially when treating wastewater with a high concentration of organic matter, the inside of the pipe may become clogged due to the proliferation of microorganisms. There was a remarkable tendency for gradual occlusion.

If the pipe line is blocked in this way, it will be impossible to treat the wastewater, so either stop the operation of the equipment and blow air up from the bottom of the vertical pipe bundle 3, or drain the water in the tank and flush it from the top. It was necessary to remove the blockage from the pipeline using methods such as:

The work to remove such blockages from pipes is very complicated and requires long periods of shutdown, and in order to minimize blockages, the amount of microorganisms must be kept low, which requires processing capacity. There was a problem with low frequency.

In order to eliminate the above-mentioned drawbacks, prevent clogging of the vertical tube bundle, and provide an oxidation treatment device for organic matter-containing wastewater with improved treatment capacity, the inventor previously proposed this type of treatment device in Japanese Patent Application No. 5333936. We have proposed a system for processing a larger amount of wastewater, in which a tank with a circular cross section is separated into an inner cylinder and an outer cylinder by a partition wall that is concentric with the outer wall of the tank. A processing apparatus provided with an oxide layer was proposed in Japanese Patent Application No. 120960/1983.

However, the state of these catalytic oxidation layers is close to complete mixing, and in order to obtain treated water with a low concentration, the concentration of organic matter in the catalytic oxidation layer must be adjusted to a value close to the concentration of treated water. The equipment will need to be operated in a larger size, or
Alternatively, it was necessary to arrange such processing devices in series to perform multi-stage processing.

The present invention is an improvement on the device disclosed in Japanese Patent Application No. 53-120960, which further improves the processing capacity and makes it possible to obtain low-concentration treated water from high-concentration organic wastewater by processing only one tank. This is the purpose.

In order to achieve this objective, the inventor conducted extensive research and found that the outer tube of the aquarium, which is partitioned into an inner tube and an outer tube by a partition wall concentric with the outer wall of the aquarium, which has a circular cross section, has an upper surface of the vertical tube bundle. A contact oxidation layer with an annular cross section formed by a vertical tube bundle, a mechanism for rotating this contact oxidation layer, and a contact oxidation layer radially outward from the center of the water tank on the bottom of the outer cylinder. A cylindrical transverse aeration pipe and an aeration pipe placed along the outer wall of the water tank at the bottom of the outer cylinder introduce wastewater that has been oxidized in the outer cylinder into the inner cylinder, and discharge sediment in the wastewater from the bottom of the inner cylinder. The wastewater oxidation treatment device is configured so as to be equipped with a discharge port for discharging the water flowing upward or downward within the contact oxidation layer. By dividing the water into blocks and gradually rotating the catalytic oxidation layer, the water partitioned into each block is transferred to the forward block one by one, without mixing with the opposite block. Blocks with different concentrations are formed.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 3A is a plan view of the wastewater oxidation treatment apparatus of the present invention, and the opening is also a sectional view taken along the line C--C.

As shown in the figure, a tank 1 having a circular cross section is partitioned into an inner cylinder 7 and an outer cylinder 8 by a partition wall 6 that is concentric with the outer wall of the tank 1.
A catalytic oxidation layer made up of a large number of vertical tube bundles 3 having a circular cross section is disposed in an annular outer cylinder 8, and a flotation air tank or tri-y funnel 9 is provided on the inner periphery of the upper end of the tube bundle 3. established,
Due to the buoyancy of this tank or float 9, the vertical tube bundle 3 is held floating so that its upper end is below the surface of the treated water in the tank 1.

On the other hand, an electric motorized reduction gear 11 is installed on a beam 10 that is bridged across the inner cylinder 7, that is, the inner upper end of the partition wall 6. A friction roller 12 is attached in contact with the tube bundle 3 so that the annular vertical tube bundle 3 can rotate.

Further, on the bottom surface of the outer cylinder 8, an aeration pipe 13a is arranged radially across the outer cylinder at an appropriate interval from the center of the aquarium, and an aeration pipe 13b is also arranged on the bottom surface of the outer cylinder along the outer wall of the aquarium to emit air. is now possible.

The inner cylinder 7 constitutes a settling tank, and a center well 14 whose upper portion projects above the water surface is provided in the center.

Next, an inlet 15 for untreated water is provided at one upper corner of the vertical tube bundle 3, and is located below the water surface of the partition wall 6 at a place turned by more than 180° in the rotational direction of the vertical tube bundle 3 from the inlet 15 for untreated water. A communication pipe 16 connecting the outer cylinder 8 and the inside of the center well 14 is provided, and an overflow gutter 17 is provided on the inner surface of the upper part of the inner cylinder 7, that is, the partition wall 6.
A treated water outlet pipe 18 is connected from this gutter 17 to the outside of the tank.

The tank bottom of the inner cylinder 7 has an inverted conical shape, and a sludge discharge port 19 is provided at the bottom.

When using the treatment device configured in this way to treat wastewater introduced into the outer cylinder 8 from the untreated water population 15, the aeration pipes 13 provided at the bottom of the outer cylinder 8 and arranged radially.
The wastewater is contained in blocks partitioned by air ejected from the aeration pipes 13b arranged along the outer walls and the aeration pipes 13b.
Convection occurs only slightly between a and the lower end of the vertical tube bundle 3, and between the upper end of the vertical tube bundle 3 and the water surface. mixing does not occur, so in the block where wastewater is introduced,
The newly inflowing amount of water flows out to other blocks, but since the vertical tube bundle 3 is rotating, most of the water flowing out to other blocks flows to the blocks in the rotation direction.

In each floc, some of the oxygen in the air ejected from the air diffusers 13a and 13b mixes with the wastewater and becomes dissolved, and most of the air from the radially arranged air diffusers 13a becomes bubbles. Climb up inside the tube bundle 3 directly above it,
This section creates an upward water flow within the tube bundle.

In addition, in the gap between the vertical tube bundle 3 and the outer wall, an upward water flow is generated by the air ejected from the diffuser tubes 13b arranged along the outer wall, so a downward flow is generated only in the remaining tube bundle 3, resulting in a circulating flow and complete mixing. In this state, organic matter in the wastewater is catalytically oxidized in the vertical tube bundle 3.

In addition, in this device, since the vertical tube bundle 3 rotates, the tube bundle through which the upward flow and the downward flow pass can be sequentially changed, and when viewed from one tube bundle, the direction of the water flow changes intermittently, and due to the downward flow, the direction of the water flow changes intermittently. It oxidizes organic matter within the pipe bundle, and the upward flow removes surplus microorganisms that are breeding inside the pipe bundle and causing clogging, preventing pipe clogging. Since a total aeration block is provided in between, microorganisms are activated by this.

In this way, each block divided into several stages by the connecting pipe 161 from the wastewater inlet 15 is formed with blocks in which the organic matter concentration gradually decreases in the rotational direction of the vertical tube bundle 3, and a plurality of wastewater treatment devices are connected in series. The device can be made smaller because it produces substantially the same capabilities as the one provided.

The treated water that has been oxidized in the contact oxidation layer and contains sludge passes through the connecting pipe 16 to the center well 1 in the center of the inner cylinder 7.
4, where the sludge settles to the bottom of the tank, and the concentrated slurry of sludge is discharged from the sludge discharge port 19 in a timely manner.

The treated water from which the sludge has been separated enters the overflow gutter 17 and is discharged outside the tank through the treated water outlet pipe 18.

Depending on the angle of the inverted cone at the bottom of the twisted inner cylinder,
If necessary, a sludge discharge device such as a rake can be installed.

If the air diffusers 13a arranged radially and the air diffusers 13b along the outer wall are divided into tubes for each block, the amount of air can be adjusted according to the amount of pollutants treated in each block. Problems caused by excessive or insufficient aeration volume can be resolved.

Note that it is preferable that the vertical tube bundle 3 rotates continuously and slowly.

As described above, the apparatus of the present invention can treat wastewater containing organic matter very efficiently, and has the advantage that a large amount of wastewater can be treated with a relatively small-sized apparatus.

[Brief explanation of the drawing]

Figure 1A and Figure 1 are a plan view of the prior art and a sectional view taken along line A-A, Figure 2A and Figure 2 are a plan view and a sectional view taken along line B-B of another example of the prior art; 3A and 3B are a plan view and a sectional view taken along the line C--C of an embodiment of the present invention. 1...tank, 3...vertical tube bundle, 6...
... Bulkhead, 7 ... Inner cylinder, 8 ... Outer cylinder, 9 ... Levitation air tank or float, 11
......Electric motorized speed reducer, 12...Friction roller, 13a, 13b...Diffuser pipe,
14...Center well 15...Untreated water inlet, 16...Connection pipe, 17...
... Overflow gutter, 18 ... Treated water outlet pipe, 19 ...
...Sludge discharge port.

Claims (1)

[Claims] 1. A vertical tube bundle is held such that the upper surface thereof is below the water surface and is formed by a vertical tube bundle inside the outer tube, which is partitioned into an inner tube and an outer tube by a partition wall that is concentric with the outer wall of the water tank, which has a circular cross section. A contact oxidation layer with an annular cross section, a mechanism for rotating this contact oxidation layer, an aeration pipe arranged radially across the outer cylinder from the center of the water tank on the bottom of the outer cylinder, and a diffuser pipe arranged along the outer wall of the water tank on the bottom of the outer cylinder. A method for oxidizing wastewater, characterized in that it is equipped with an aeration pipe disposed in the outer cylinder, and an outlet for introducing the wastewater oxidized in the outer cylinder into the inner cylinder and discharging the sediment in the wastewater from the bottom of the inner cylinder. Processing equipment.