JP2002320827A - Solid-liquid separation equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid-liquid separation equipment capable of continuously carrying out efficient solid-liquid separation operation while making good use of the advantages of a membrane separator having a washing nozzle. SOLUTION: A plurality of membrane separation vessels 12 each housing an immersion membrane module 13 and having a washing nozzle 18 which blows washing water on the filtration surface of the membrane module in the upper part of the vessel 12 are arranged in parallel behind a sedimentation tank 11 and each of the membrane separation vessels 12 and the sedimentation tank 11 are connected by a channel 23 with a water shutoff means 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-liquid separation apparatus, and more particularly to a solid-liquid separation apparatus in which a sedimentation is provided at a stage preceding a membrane separation tank provided with a washing nozzle for washing a filtration surface above a membrane separation tank containing a submerged membrane module. The present invention relates to a solid-liquid separation device having a tank.

[0002]

2. Description of the Related Art It is expected that contaminants in influent sewage will increase due to the recent spread of disposers. In a sewage treatment plant, secondary treatment by floating sludge in a final sedimentation basin is considered. Deterioration of water quality is a problem. For this reason, the secondary treatment water flowing out of the final sedimentation basin is being discharged after being further filtered.

[0003] As a method for treating the secondary treated water, a rapid filtration method and a micro-strainer are generally used. However, these methods have problems in terms of an installation area and the like, and are used as filtration treatment devices for solving this problem. JP-A-2000-6
A solid-liquid separation device (membrane separation device) described in Japanese Patent No. 2833 has been proposed.

In this membrane separation apparatus, a washing nozzle for washing a filtration surface is provided above a solid-liquid separation tank (membrane separation tank) accommodating an immersion type membrane module, so that the filtration surface can be efficiently washed. Since it is possible to reduce the distance between the membrane modules, it is possible to obtain a sufficient filtration area even with a small installation area, and it has an advantage that the filtration speed is excellent and the maintenance can be easily performed. Have.

However, when washing the filtration surface of the membrane module with the washing nozzle, it is necessary to discharge the water in the membrane separation tank, and depending on the scale of the apparatus, the membrane is separated from the drainage operation through the washing operation again. It may take a long time before water is injected into the tank and the filtration operation is restarted, and the water treatment efficiency may be reduced.

Accordingly, an object of the present invention is to provide a solid-liquid separation device capable of continuously performing an efficient solid-liquid separation operation while taking advantage of the membrane separation device having the washing nozzle.

[0007]

In order to achieve the above-mentioned object, a solid-liquid separation device of the present invention is provided with washing water directed toward a filtration surface of a membrane module above a membrane separation tank containing a submerged membrane module. A plurality of membrane separation tanks each having a washing nozzle to be ejected are arranged in parallel at the subsequent stage of the settling tank, and each of the membrane separation tanks and the settling tank are connected to each other via a path provided with a water stopping means. And

[0008]

1 and 2 show an embodiment of a solid-liquid separation apparatus according to the present invention. FIG. 1 is a system diagram showing a flow of water, and FIG. 2 is a membrane separation tank and a sedimentation tank. FIG. 4 is a schematic plan view showing an arrangement state of FIG. This solid-liquid separation device is formed such that a plurality of membrane separation tanks 12 are arranged in parallel at the subsequent stage of the precipitation tank 11, and the treated water precipitated in the precipitation tank 11 is further subjected to membrane separation in the membrane separation tank 12. .

The membrane separation tank 12 holds a plurality of membrane modules 13 having two planar filter materials, such as a fine mesh screen and a filter cloth, facing each other and sealing the outer periphery thereof with a frame material at predetermined intervals by spacers. It is arranged vertically, and a part of the frame material on the side of the membrane module 13
4 is formed, and the membrane treatment water subjected to the solid-liquid separation treatment in the membrane module 13 is formed so as to overflow the weir of the overflow chamber 15 from the water inlet 14 and flow down to the treatment water tank 17 from the path 16. ing.

[0010] Further, washing water is jetted toward the filtration surfaces on both sides of the membrane module 13 above the membrane separation tank 12, and a washing nozzle 18 for washing the filtration surface with the washing water.
Is provided. Further, the top plate 19 of the membrane separation tank 12 is provided with an air release valve 20 which opens when draining or pouring water, and a drain valve 2 for discharging washing drainage is provided at the bottom.
1 is provided.

The membrane separation tank 12 formed as described above is
As shown in FIG. 2, a plurality of the membrane separation tanks 12 and the sedimentation tanks 11 are arranged in parallel at the subsequent stage of the settling tanks 11. Each is connected.

The raw water to be subjected to the solid-liquid separation treatment flows from the inflow pipe 31 into the sedimentation tank 11, where the sedimentation treatment is performed. The sludge settled at the bottom of the tank is withdrawn from the drain valve 32, and the supernatant water that has passed through the weir 33 passes through the water supply path 23 to each of the membrane separation tanks 12.
Flows into. In the membrane separation tank 12, a membrane separation process is performed by the membrane module 13, and treated water flows from the path 16 through the treatment tank 1
Outflow to 7.

When cleaning the membrane module 13, one of the plurality of membrane separation tanks 12 is selected. First, the water stopping means 22 of the water supply path 23 leading to the membrane separation tank 12 for performing membrane cleaning is operated to shut off the inflow water from the sedimentation tank 11, and the air release valve 20 and the drain valve 21 of the membrane separation tank 12. To drain the water in the tank. Subsequently, the washing water pump 34 is operated and the membrane separation tank 12 is operated.
Is opened, and the cleaning water is supplied from the treatment water tank 17 to the cleaning nozzle 18 of the membrane separation tank 12.

As a result, the filtration surface of the membrane module 13 installed in the membrane separation tank 12 is washed by the washing water spouting from the washing nozzle 18 toward the filtration surface, and the washing wastewater is drawn out through the drain valve 21. It is. Further, if necessary, a chemical solution can be supplied from a chemical solution tank (not shown) to the cleaning nozzle 18 to clean the membrane module 13 with the chemical solution.

When the washing of the membrane module 13 is completed, the washing water pump 34 is stopped, the washing valve 35 is closed, the drain valve 21 is closed, and the water stopping means 22 is opened to move the washing water from the sedimentation tank 11 into the membrane separation tank 12. Allow water to flow in. And
When the water level in the tank reaches a predetermined height, the air release valve 2
When 0 is closed, membrane separation in the membrane module 13 resumes due to the head difference from the sedimentation tank 11.

After the cleaning of the membrane module 13 installed in one membrane separation tank 12 is completed, the next membrane cleaning of the membrane separation tank 12 is performed. Therefore, as shown in this embodiment, when five membrane separation tanks 12 are provided in parallel, the membrane separation process is continuously performed in four tanks other than the membrane module 13 being washed. Therefore, by designing the amount of water and the like based on the four membrane separation tanks 12,
A predetermined amount of film processing can always be performed.

Further, compared with the case where the entire membrane is formed as one membrane separation tank, the amount of water discharged when cleaning the membrane module 13 and the amount of water introduced for restarting the membrane separation process can be reduced. The downtime of the membrane separation tank 12 that cleans the water can be shortened.

[0018]

As described above, according to the solid-liquid separation apparatus of the present invention, the solid-liquid separation process by the membrane separation can be continuously performed even when the membrane module is washed, so that an efficient solid-liquid separation can be performed. Liquid separation can be performed.

[Brief description of the drawings]

FIG. 1 is a system diagram showing one embodiment of a solid-liquid separation device of the present invention.

FIG. 2 is a schematic plan view showing an arrangement state of a membrane separation tank and a precipitation tank.

[Explanation of symbols]

11: sedimentation tank, 12: membrane separation tank, 13: membrane module,
14 ... water inlet, 15 ... overflow chamber, 16 ... route, 17 ... treated water tank, 18 ... washing nozzle, 19 ... top plate, 20 ... air release valve, 21 ... drain valve, 22 ... water stopping means, 23 ...
Water supply path, 31: Inflow pipe, 32: Drain valve, 33: Weir, 3
4: Cleaning water pump, 35: Cleaning valve

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) B01D 29/04 530A 29/38 510A

Claims (1)

[Claims] 1. A plurality of membrane separation tanks, each having a washing nozzle for jetting washing water toward a filtration surface of the membrane module disposed above a membrane separation tank containing an immersion type membrane module, are arranged in parallel at the subsequent stage of the settling tank. A solid-liquid separation device, wherein each of the membrane separation tanks and the sedimentation tank is arranged via a path provided with a water stopping means.