JP3374766B2 - Anaerobic treatment equipment for organic wastewater - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to granules composed of anaerobic microorganisms forming sedimentation layers and self-granulating sludge (precursor of small particle size) for organic matter in organic wastewater. It is also referred to simply as sludge.) Finally, it decomposes into anaerobic gas consisting mainly of methane and carbon dioxide to remove organic matter, and the treated water after decomposition of organic matter is removed from the generated anaerobic gas and sludge. The present invention relates to a UASB type (upflow sludge blanket type) anaerobic treatment device that is separated and taken out.

[0002]

2. Description of the Related Art The applicant of the present patent application is Japanese Patent Application No. 10-1024.
No. 91 anaerobic sludge layer at the bottom, and in the water above the reaction section inside the treatment tank having a reaction section having a water supply pipe for supplying organic wastewater in the sludge layer in an upward flow, While arranging by immersing the conical precipitation part with the pointed part facing downward, the upper end projects above the liquid surface in the tank around the precipitation part, and the lower end part is in the middle of the height of the precipitation part. An upright tubular wall located in water, an inclined wall approaching from the lower end of the upright tubular wall toward the lower end of the settling section, and an upright tubular wall above the settling section is constricted downward and the lower end is A partition wall equipped with an overflow gutter that rushes into the settling section shallowly from above and at the top of which the treated water overflows from the liquid level in the tank, and the lower end of the upright cylindrical wall provided on the outer surface of the settling section. Baffle plate that projects obliquely downward toward the inner surface of the part, and sludge that accumulates at the bottom of the settling part is discharged to the outside of the settling part and the reaction part Proposed anaerobic treatment apparatus of the organic waste water having a sludge return pipe which connects the return pump to return.

[0003]

In the above-mentioned prior device, sludge settled on the bottom of the pyramid-shaped settling part with the pointed tip facing downward uses the sludge return pipe connected to the return pump, and the sludge return pipe is operated by the operation of the return pump. Although it is returned to the reaction section, if the flow of sludge into the settling section increases, it cannot be completely removed by the return pump, and the space in the settling section may not be effectively used for sedimentation separation. For that purpose, the number of operating pumps, the operating time, and the frequency must be adjusted so that the sludge is not stored in the sedimentation section as much as possible, and the operation becomes complicated.

[0004]

The present invention was developed in order to solve the above-mentioned problems. An anaerobic treatment apparatus for organic wastewater according to claim 1 has an anaerobic sludge layer at the bottom, and A pyramidal sedimentation part with the tip facing downward in water above the reaction part inside the treatment tank having a reaction part having a water supply pipe for supplying organic wastewater in an upward flow into the sludge layer While arranging by immersing, the upper end portion projects above the liquid surface in the tank around the settling section, and the lower end section is positioned in the water in the middle of the height of the settling section, and the upright tube. An inclined wall approaching from the lower end of the wall toward the lower end of the settling section, and the inside of the upright cylindrical wall above the settling section is constricted downward and the lower end rushes into the inside of the settling section shallowly from above, A partition wall with an overflow gutter at the top where treated water overflows from the liquid level inside the tank, and an outer surface of the settling section. In anaerobic treatment apparatus of the organic waste water which is provided a baffle plate which projects obliquely downward toward the lower end portion inner surface of the cylindrical wall, characterized in that a baffle of chevron cross-section at the lower end of the precipitation section. The anaerobic treatment apparatus for organic wastewater according to claim 2 is the anaerobic treatment apparatus for organic wastewater according to claim 1, wherein one end is opened inside the bottom of the settling section and the other end is a tank. Inside of the baffle with the chevron cross section, the lower end opens, and the upper end is the upper end of the baffle with the chevron cross section, and the sludge return pipe that protrudes above the inner liquid surface and then folds downward and projects into the liquid surface inside the tank outside the partition wall. An upward gas vent pipe connected in the middle of the sludge return pipe is provided, and the anaerobic gas generated in the reaction section and collected by the baffle is supplied to the sludge return pipe by the gas vent pipe, and sludge return is performed. It is characterized in that the sludge collected by the baffle by the gas lift action generated in the pipe and the sludge settled at the bottom of the settling section are returned to the reaction section.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In each of the embodiments of FIGS. 1, 2 and 3, 10 is a covered treatment tank having a gas vent pipe 10 'at the top, and 12 is sludge formed inside the treatment tank. An anaerobic sludge layer, 13 is a water supply pipe for supplying raw water (organic wastewater) into the anaerobic sludge layer for upward flow, and the sludge constituting the anaerobic sludge layer is treated by upward flow raw water. Deploys in a fluid state up to the middle of the height. Raw water supply pipe 1
3 and the anaerobic sludge layer 12 that develops in a fluidized state constitute a reaction section 11 in the lower half of the treatment tank.

A pyramidal hollow settling section 14 with its tip facing downward is disposed by being immersed in water above the reaction section 11 inside the processing tank 10, and the treatment tank is An upright cylindrical wall 15 having an upper end projecting above the liquid surface W in the tank and a lower end located in water halfway along the height of the settling section, and a lower end of the upright tubed wall to a lower end of the settling section. An inclined wall 16 approaching toward the bottom of the settling section, a partition wall 17 in which the lower half portion is narrowed downward and the lower end is projected into the inside of the settling section from above from the upper part of the upright tubular wall 15 and the partition wall 17. Standing along the inside of the wall 17, a standing wall 18 that forms a treated water overflow gutter 19 with the partition wall and an outer surface of the settling portion, which is slanted toward the inner surface of the lower end portion of the upright tubular wall. The baffle plate 20 that projects downward is provided.

The upper end of the partition wall 17 projects above the liquid surface W, but since it has a deep V-shaped cutout 17 'facing downward, the liquid outside the partition wall passes through the V-shaped cutout and flows into the overflow trough 19. enter. Further, since the upper end of the standing wall 18 is lower than the partition wall and has a shallow V-shaped cut 18 'which is almost at the same level as the liquid surface, the liquid inside the standing wall 18 overflows the trough through the V-shaped cut. 1
Enter 9. The liquid that has entered the overflow gutter 19 is discharged as treated water outside the treatment tank 10 through a drain pipe 21.

The upright cylindrical wall 15 is fixed to the inner wall of the processing tank by an appropriate means such as a support arm. The treatment tank may be a cylindrical tank or a polygonal cylinder tank.

The upright tube wall 15 is a square tube having a square or rectangular shape in plan view and extends along the inner sides of the left and right side walls 15a, 15a, with its end portions facing end walls 15b, 15 of the upright tube wall.
Left and right partition walls 17 and standing walls 18 are provided by fixing to b. As a result, two overflow gutters 19 are independently formed on the left and right sides, and therefore a drain pipe 21 for treated water is provided for each overflow gutter 19.

Also in the settling portion 14 in which the lower end portions of the left and right partition walls 17 which are narrowed downward are projected from above, the left and right upper portions 14 ', 14' of the inverted C-shape are opposed to each other by the end walls 15 of the upright cylindrical wall.
It is fixed to b and 15b. The settling portion 14 includes the left and right upper portions 14 ', 14' and the end walls 15b, 15b.
It is a hollow quadrangular pyramid that extends downward from.

The upright cylindrical wall 15 is provided on the outer surface of the sedimentation portion.
The left and right baffle plates 20 projecting obliquely downward toward the inner surface of the lower end of each of the end portions together with the upper portions 14 ', 14' of the settling portion are formed in a square shape on opposite end walls 15b, 15b of the upright cylindrical wall. It is fixed to.

Then, the left and right inclined walls 16, 16 approaching from the lower end of the upright cylindrical wall 15 toward the lower end of the settling portion 14.
The left and right side walls 15a, 15a of the upright cylindrical wall 15 are formed to extend obliquely downward.

End walls 15b, 15b of the upright cylindrical wall which face each other.
A notch 22 is formed along the left and right baffle plates 20, 20 from the lower ends of the left and right inclined walls 16, 16 and the opposite end walls 14a, 14a of the upper end of the quadrangular pyramid settling portion 14. .

In this embodiment, although not shown, one processing section having a square upright cylindrical wall 15 smaller than that is installed in the central portion of a rectangular processing tank 10 having a square planar shape. The number of processing units installed is arbitrary and the processing tank 10
It may be determined as appropriate according to the size of the plane shape.

Hollow quadrangular pyramid settling section 1 with the top facing down
4, a baffle 23 having a chevron section with the top facing upward is provided at the lower end of the downward facing top. Although the baffle 23 of the embodiment of FIGS. 1 and 2 is a hollow quadrangular pyramid, the left and right ends of the quadrangular pyramid of FIG. 2 are equal to or greater than a distance of 15b. And, as shown in FIG. 3, the baffle may have a hollow gable roof shape. The distance between the gable plates of the gable roof baffle is preferably equal to or longer than the distance between the end walls 15b and 15b of the upright cylindrical wall.

Raw water (organic sewage), which is supplied from the water supply pipe 13 into the treatment tank and flows upward in the reaction section 11, spreads the anaerobic sludge layer 12 into a fluid state and comes into contact with the sludge to contain the organic matter. Is decomposed by anaerobic microorganisms into treated water, and the treated water accompanies the anaerobic gas that is generated by the decomposition and floats, and further flows upward from the reaction section 11 together with some sludge.

A part of the treated water containing upward gas and sludge is collected by the baffle 23. The treated water and the gas containing the remaining sludge flow upward around the baffle 23, and a part of the treated water and gas narrow the lower end of the upright cylindrical wall 15 and the left and right inclined walls 1
6, 16 and the rising water channels 25 and 25 around the upright cylindrical wall, that is, between the left and right side walls 15a and 15a of the cylindrical wall and the inner wall of the treatment tank, and the end walls 15b and 15b and the inner wall of the treatment tank. Between the rising water channels 26, 26 and adjacent walls 15a, 15a and 15b, 15 of the upright cylindrical wall when a plurality of processing units are provided.
Ascending in the ascending water channel between b, the gas floats on the liquid surface and is discharged to the outside from the degassing pipe 10 '. The remaining treated water and gas flow between the lower ends of the left and right inclined walls 16 and 16 and the sedimentation section 14,
And the upright cylinder wall 15 and the baffle plate 2 through the notches 22 and 22 formed in the end walls 15b and 15b of the upright cylinder wall facing each other.
Ascending through 0 and rising, some gas is trapped by baffle plate 20. A part of the treated water and the gas is directed upward between the partition wall 17 and the upright cylindrical wall 15, the gas floats above the liquid surface and is discharged from the degassing pipe, and the treated water is cut into the notch 17 of the partition wall 17. ′
Flows into the overflow gutters 19 and 19 and is discharged to the outside of the system by the drain pipes 21 and 21.

The balance of the gas and treated water that rises through the space between the upright cylindrical wall 15 and the baffles 20 and 20 is the partition walls 17 and 17.
Between the lower end of the bottom and the upper part 14 ', 14' of the settling part 2
Left and right partition walls 17, 17 passing downward through 8, 28
However, due to the difference between the ascending velocity and the sedimentation velocity of the sludge, the sludge settles in the sedimentation section 14, the gas floats to the liquid surface and is discharged through the degassing pipe, and the treated water flows into the standing walls 18 and 18. The overflow pipes 19 and 19 overflow from the notch 18 'provided, and the drain pipe 2
1, 21 are drained out of the system.

In this manner, a part of the sludge contained in the treated water flowing upward from the reaction section along with the anaerobic gas and a part of the anaerobic gas are collected by the baffle 23. Therefore, the precipitation part 1
The amount of sludge settling in No. 4 is small and the amount of sludge mixed with the treated water and flowing out to the overflow gutters 19 and 19 is also small, so that treated water with good water quality can be obtained.

Sludge collected in the baffle 23, sedimentation section 1
In order to return the sludge settled to No. 4 to the reaction section 11, one end is opened inside the bottom of the settling section 14 and the other end is projected above the liquid level in the tank and then folded back to the outside of the partition wall 17. At the bottom of the baffle 23, a return pipe 29 for sludge that is open on the liquid surface in the tank or that rushes into the liquid surface is opened at the bottom, and the top of the baffle 23 is penetrated through the wall of the sedimentation portion 14. A gas vent pipe 30 connected to the sludge return pipe 29 is provided. As a result, the anaerobic gas collected by the baffle rises in the gas vent pipe 30 and flows into the sludge return pipe 29, and the partition wall 17
It is returned to the tank outside. The sludge collected in the baffle and the sludge settled in the settling section can be returned to the reaction section 11 by the airlift action of the anaerobic gas. Sludge return pipe 2
An automatic valve V whose opening / closing operation is controlled by a timer may be provided at 9 upstream of the position to which the gas vent pipe 30 is connected.
Further, in order to improve the gas list efficiency, a receiving tank (not shown) may be provided at the highest rising portion of the return pipe 29.

[0021]

According to the invention of claim 1, since the baffle collects sludge in the treated water flowing upward with the anaerobic gas, the sludge inflow to the settling section is reduced, and the space in the settling section is effective for settling separation. Available for Further, according to the invention of claim 2, the sludge collected in the baffle and the sludge settled in the sedimentation part can be returned to the reaction part by the airlift action of the anaerobic gas collected in the baffle. Therefore, since it is not necessary to use a pump, equipment cost and running cost are reduced.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of an embodiment of an anaerobic treatment apparatus of the present invention.

2 is a vertical side view of the processing apparatus of FIG. 1. FIG.

FIG. 3 is a vertical sectional side view similar to FIG. 2 of another embodiment of the processing apparatus of the present invention.

[Explanation of symbols]

10 Treated tank with a lid 10 'degassing tube 11 Reaction part 12 Anaerobic sludge layer in the reaction section 13 Raw water supply pipe of reaction section 14 sedimentation part 15 Upright cylinder wall 15a Side wall of upright cylinder wall 15b End wall of upright cylinder wall 16 inclined wall 17 partition walls 17 'V-shaped cut in partition wall 18 standing wall 18 'V-shaped notch on upright wall 19 overflow gutter 20 baffle 21 Drainage pipe for treated water 22 Notch in end wall of upright cylinder wall 23 baffle 25 ascending canal 26 ascending canal 29 Sludge return pipe 30 degassing tube

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) C02F 3/28-3/34

Claims (2)

(57) [Claims] 1. Water above the reaction section inside a treatment tank having a reaction section having an anaerobic sludge layer at the bottom and a water supply pipe for supplying organic wastewater into the sludge layer in an upward flow. In, place the cone-shaped precipitation part with the tip facing downward, and place it,
An upright cylindrical wall having an upper end projecting above the liquid surface in the tank around the settling section and a lower end located in the water in the middle of the height of the settling section, and the settling section from the lower end of the upright tube wall. The slanted wall approaching toward the lower end of the settling wall, and the inside of the upright cylindrical wall above the settling section is narrowed downward and the lower end is projected into the settling section from the top at a shallow depth. A partition wall provided with an overflow gutter for the treated water to overflow, and a baffle plate that is provided on the outer surface of the settling section and that projects obliquely downward toward the inner surface of the lower end portion of the upright tubular wall. An anaerobic treatment apparatus for organic wastewater, wherein a baffle having a chevron cross section is arranged at the lower end of the precipitation section. 2. The apparatus for anaerobic treatment of organic wastewater according to claim 1, wherein one end has an opening inside the bottom of the settling section, and the other end projects downward on the liquid surface in the tank. A sludge return pipe that folds back and plunges into the liquid level in the tank outside the partition wall, and a lower end opens inside the top of the baffle with the chevron cross section, and the upper end connects upwards in the middle of the sludge return pipe. And a bleeder tube for the anaerobic gas generated in the reaction section and collected in the baffle is supplied to the sludge return pipe by the gas bleeder tube, and is collected in the baffle by the gas lift action generated in the sludge return pipe. An anaerobic treatment apparatus for organic wastewater, wherein the sludge and the sludge settled to the bottom of the settling section are returned to the reaction section.