JP2000061491A - Anaerobic water treatment equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely retain a large amount of granules in a reactor. SOLUTION: This equipment is provided with a reactor 2, granules 3 received in the reactor 2 and a membrane separator 4 placed in the reactor 2. In the equipment, treated water subjected to treatment in the reactor 2, together with the granules 3, is transferred to the membrane separator 4 and the treated water separated from the granules 3 in the membrane separator 4, is discharged from the separator 4 to the outside of the equipment by using a withdrawal pump 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anaerobic water treatment device that anaerobically treats water.

[0002]

2. Description of the Related Art With the development of the UASB method, many anaerobic treatments have been introduced in the industrial wastewater treatment field mainly in the food industry in recent years. The UASB method is an anaerobic water treatment using granules that are self-granulated products of methane bacteria. The UASB method can maintain a high microbial cell concentration, so an aerobic treatment (activated sludge method) It is possible to treat with a high load of about 20 times that of the above, and it is also possible to adapt to high concentration wastewater.

FIG. 12 shows a typical processing flow of the UASB method. Waste water (water to be treated) is introduced into the lower part of the methane fermentation reactor 2 by the raw water pump 1. Organic matter in the water to be treated is decomposed by methane bacteria (granule 3) in the reactor and becomes methane gas and is discharged to the outside of the system. The treated water from which organic substances have been removed by the methane bacteria is discharged as treated water from the upper part of the reactor.

Further, the methane gas generated by the methane bacteria may adhere to the granules and float up, and the granules may flow out of the system together with the treated water. To prevent this, a gas-solid separation device (GSS) is used. 19 is provided above the reactor 2.

Therefore, the inside of the reactor 2 is a granule 3
Part, the supernatant phase 2a and the GSS 19 part can be divided into three layers.

[0006]

The upper limit of the amount of organic substances to be treated per weight of the granule 3 is fixed.
Therefore, in order to perform a high load operation, it is necessary to increase the amount of granules 3 in the reactor 2. However, when the amount of the granules 3 is increased, the supernatant phase 2a decreases, so that the granules 3 easily flow out together with the treated water.

Further, since the amount of gas generated increases as the load increases, the conventional GSS19 cannot perform sufficient gas-solid separation, and the granules 3 are more likely to flow out.

When the outflow of the granules 3 increases, the amount of the granules 3 in the reactor 2 decreases and high load operation cannot be performed. At the same time, the amount of organic substances added per granule 3 increases, which causes a decrease in treatment efficiency (removal rate).

The present invention has been made in consideration of such a point, and a large amount of granules can be retained in the reactor, which enables an efficient operation under a high load. The purpose is to provide a water treatment device.

[0010]

The present invention is directed to a reactor having granules, which treats wastewater with the granules to produce treated water, and a membrane separation device installed in the reactor for separating the granules from the treated water. An anaerobic water treatment apparatus comprising: an apparatus and a drawing pump for drawing treated water from a membrane separation apparatus.

According to the invention, wastewater is introduced into the lower part of the reactor. Organic matter in the wastewater is decomposed by methane bacteria (granule) in the reactor and becomes methane gas, which is discharged to the outside of the system. The treated water from which organic substances have been removed by the methane bacteria is discharged by a drawing pump that draws the treated water from the membrane separator through the membrane separator installed in the reactor. At this time, the methane bacteria are prevented from flowing out of the system together with the treated water by the membrane separation device, and as a result, the amount of methane bacteria in the reactor can be increased, which enables high-load treatment. Become.

The present invention has a granule, a reactor for treating wastewater with the granule to produce treated water, a circulation tank for taking out the treated water in the reactor, and the treated water in the circulation tank to the lower part of the reactor. A first circulation line having a first circulation pump that circulates; a membrane separator installed in the circulation tank for separating granules from the treated water; and a drawing pump for drawing the treated water from the membrane separator. Is an anaerobic water treatment device.

According to the invention, wastewater is introduced in the lower part of the reactor. Organic matter in the wastewater is decomposed by methane bacteria (granule) in the reactor and becomes methane gas, which is discharged to the outside of the system. The treated water from which organic substances have been removed by the methane bacteria is guided to the circulation tank, and is discharged by the drawing pump through the membrane separation device installed in the circulation tank. The treated water in which the methane bacteria has been concentrated by the membrane separator is returned from the circulation tank to the lower part of the reactor by the first circulation line having the first circulation pump. At this time, the methane bacteria are prevented from flowing out of the system together with the treated water by the membrane separation device, and as a result, the amount of methane bacteria in the reactor can be increased, which enables high-load treatment. Become. Further, since the membrane separation device can be installed in the circulation tank outside the reactor, maintenance such as replacement of the membrane separation device can be easily performed.

The present invention is an anaerobic water treatment apparatus characterized in that an air diffusing pipe is provided in the lower part of the membrane separation device, and the reactor upper part and the diffusing pipe are connected by a biogas circulation line having a blower.

According to the present invention, a biogas circulation line for cleaning the membrane surface of the membrane separation device is provided, and the membrane surface of the membrane separation device is gas-cleaned by an air diffusing pipe provided at the bottom of the membrane separation device. As a result, the membrane can be prevented from being blocked, and the membrane separation device can be stably operated for a long period of time.

The present invention is the anaerobic water treatment apparatus characterized in that a second circulation line having a second circulation pump for returning the treated water in the upper portion of the reactor to the lower side of the membrane separation apparatus is provided.

According to the present invention, the treated water in the upper part of the reactor is returned to the lower side of the membrane separation device by the second circulation line having the second circulation pump, so that the membrane surface velocity of the membrane separation device is secured and the membrane separation device is secured. The membrane can be prevented from being blocked.

The present invention is an anaerobic water treatment apparatus, characterized in that a gas collector for cleaning the gas of the membrane separator with a biogas from the granules is provided below the membrane separator.

According to the present invention, by providing the gas collector in the reactor, it is possible to wash the membrane separation device with biogas to prevent clogging of the membrane, and the stable operation of the membrane separation device for a long period of time is possible. Becomes

The present invention has a granule, a reactor for treating wastewater with the granule to produce treated water, a treated water tank installed on the upper part of the reactor, and a granule from treated water installed in the treated water tank. A membrane separation device for separating the water, a drawing pump for drawing the treated water from the membrane separation device,
An anaerobic water treatment device comprising: a gas collector for collecting treated water and biogas in a reactor and guiding the treated water to a treated water tank; and a return line for returning the treated water in the treated water tank to the reactor. .

According to the present invention, the treatment tank is installed in the upper part of the reactor, and the membrane separator is installed in the treated water tank. Therefore, the biogas generated from the reactor is treated by the gas holdup together with the treated water by the gas collector. Lead to the treated water tank and stir in the treated water tank. As a result, the membrane surface flow velocity can be secured to prevent clogging of the membrane of the membrane separation device, and stable operation of the membrane separation device for a long period of time becomes possible.

According to the present invention, a gas line for introducing nitrogen gas and having an opening / closing valve is provided below the gas collector in the rear tank, and a gas meter for detecting the amount of gas generated is provided in the treated water tank, based on a signal from the gas meter. It is an anaerobic water treatment device characterized by controlling an on-off valve by a control device.

According to the present invention, the gas line for introducing the nitrogen gas and the gas meter for detecting the gas generation amount are provided, so that the nitrogen gas is introduced at the initial stage of start-up or when the biogas generation amount is lowered for some reason. By doing so, the membrane surface of the membrane separation device is cleaned. As a result, the membrane surface velocity of the membrane separation device can be secured regardless of the gas generation amount, so that clogging of the membrane can be prevented, and stable long-term operation of the membrane separation device becomes possible.

The present invention is the anaerobic water treatment apparatus characterized in that the reactor is provided with a sensor for detecting the water level in the reactor, and the withdrawal pump is controlled by the controller based on the signal from the sensor.

According to the present invention, the sensor for detecting the water level in the reactor is provided, and the water level in the reactor is always kept constant by detecting the water level in the reactor by this sensor and controlling the drawing flow rate of the drawing pump. I can do things. Therefore, it is possible to prevent the biogas from flowing out into the treated water due to the decrease in the water level in the reactor. Further, it is possible to prevent the treated water from flowing out into the biogas line due to the rise of the water level in the reactor.

The present invention is the anaerobic water treatment apparatus characterized in that the reactor is provided with a sensor for detecting the water level in the reactor, and the blower is controlled by the controller based on the signal from the sensor.

According to the present invention, the sensor detects the water level in the reactor, and the result determines the degree of fouling of the membrane surface. Next, by controlling the circulation flow rate of the biogas, it becomes possible to remove the dirt on the membrane surface of the membrane separator and to stably discharge the treated water.

According to the present invention, an air diffuser is provided in the lower part of the membrane separation device, a gas line for introducing nitrogen gas into the air diffuser and an on-off valve is provided, and a sensor for detecting the water level in the reactor is provided in the reactor. An anaerobic water treatment system characterized in that a control device controls an on-off valve based on a signal from the anaerobic water treatment system.

According to the present invention, the sensor detects the water level in the reactor, and the result determines the degree of fouling of the membrane surface of the membrane separation device. When the dirt on the membrane surface is detected, nitrogen gas is supplied from the gas line to the membrane separation device through the air diffuser to clean the membrane separator. This makes it possible to remove the dirt on the film surface and to stably discharge the treated water.

The present invention is an anaerobic water treatment apparatus characterized in that a partition plate for dividing the inside of the reactor into a plurality of regions is provided, and a membrane separation device is provided in each region surrounded by the partition plate. .

According to the present invention, since the inside of the reactor is divided into a plurality of regions by the partition plate and the membrane separation device is installed in each region, the separation action by the membrane separation device can be efficiently performed.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION First Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a first embodiment of an anaerobic water treatment system according to the present invention.

As shown in FIG. 1, the anaerobic water treatment device is
It has a methane fermentation reactor (UASB reactor) 2 and granules (methane bacteria) 3 filled in the reactor 2. Waste water (water to be treated) is supplied to the reactor 2 by the raw water pump 1, and anaerobic water treatment is performed in the reactor 1 by the granules 3. At this time, treated water and biogas are generated, of which biogas is discharged through the biogas pipe 20.

Further, as shown in FIG. 1, a membrane separator 4 is installed inside the reactor 2, and the membrane separator 4 is provided.
The treated water that has been membrane-separated in (1) is taken out of the system via the drawing pump 5.

Next, the operation of this embodiment having such a configuration will be described.

Waste water (water to be treated) that has flowed into the methane fermentation reactor 2 via the raw water pump 1 flows in the reactor 2 in an upward flow. Organic matter in the water to be treated is decomposed by the granules 3 filled in the methane fermentation reactor 2 to become biogas, which is released to the outside of the system, and at the same time, treated water is produced.

At this time, the granules 3 adhere to the generated biogas, float on the liquid surface, and flow out of the system together with the treated water, so that the amount of granules inside the methane fermentation reactor 2 decreases and the removal rate increases. It is also possible to cause a decrease. In addition, when the operation is performed under a high load, it is conceivable that the gas generation amount increases as the load increases and the outflow of the granules 3 is accelerated.

In this embodiment, solid-liquid separation of treated water and granules 3 is carried out by a membrane separation device 4 inserted in the reactor 2, and only treated water is discharged by a drawing pump 5 to the outside of the system. Therefore, the outflow of the granules 3 can be prevented.

As described above, according to the present embodiment, the treated water in the methane fermentation reactor 2 is subjected to solid-liquid separation in the membrane separation device 4 and discharged to the outside of the system, so that the outflow of the granules 3 is prevented. It can be prevented. As a result, the granules 3 in the methane fermentation reactor 2 can be maintained at a high concentration, so that high load operation can be performed. Further, since the concentration of the granules 3 in the methane fermentation reactor 2 can be maintained at a high concentration, the load amount per granule 3 can be relatively reduced, and thus highly efficient operation can be performed.

Further, in the conventional method, it was necessary to provide the supernatant phase 2a having the same depth on the upper part of the granule 3 phase, but in the present invention, the supernatant phase 2a can be made small. , The volume of the methane fermentation reactor 2 is, for example, 2 /
It can be reduced to about 3.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIG.

In the second embodiment shown in FIG. 2, the same parts as those in the first embodiment shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 2, the methane fermentation reactor 2
The circulation tank 6 is connected to, and a first circulation line 7a having a first circulation pump 7 is connected between the circulation tank 6 and the reactor 2. The supernatant water in the reactor 2 is guided to the circulation tank 6,
It is circulated to the lower part of the reactor 2 by the first circulation pump 7. The membrane separator 4 is installed inside the circulation tank 6, and the treated water membrane-separated by the membrane separator 4 is taken out of the system via the treated water pump 5.

In FIG. 2, the treated water and the granules 3 are sent to the circulation tank 6 and solid-liquid separation is carried out by the membrane separation device 4 inserted inside the circulation tank 6. In addition, the membrane separation device 4
The treated water containing the granules 3 separated in (1) is returned to the lower part of the reactor 2 via the first circulation line 7 a having the first circulation pump 7.

According to the present embodiment, since the membrane separation device 4 is installed outside the reactor 2, it is possible to replace the membrane separation device 4 when it is deteriorated without opening the reactor 2. Therefore, the man-hours involved in the replacement work can be significantly reduced. Further, a plurality of circulation tanks 6 may be installed. In this case, the maintenance of the membrane separation device 4a can be performed sequentially, and the membrane separation device 4 can be replaced without stopping the operation of the reactor 2.

Third Embodiment Next, an embodiment of the present invention will be described with reference to FIG.

In FIG. 3, the same parts as those of the first embodiment shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 3, the methane fermentation reactor 2
A membrane separation device 4 is installed inside, and the treated water subjected to membrane separation by the membrane separation device 4 is taken out of the system via a drawing pump 5. Further, an air diffuser 9 is provided in the lower part of the membrane separation device 4, and a part of the biogas generated from the reactor 2 is guided from the upper part of the reactor 2 to the air diffuser 9 through a biogas circulation line 8a having a blower 8 to form a membrane. Separator 4
The film surface of can be cleaned with gas.

In FIG. 3, a part of the biogas generated from the methane fermentation reactor 2 is partially separated by a membrane separation device 4 via a biogas circulation line 8a connected to the upper part of the reactor 2.
Is guided to the air diffuser 9 installed in the lower part of the. The biogas aerated from the air diffuser 9 then cleans the membrane surface of the membrane separation device 4 with gas.

As described above, according to the present embodiment, since the membrane separation device 4 can be constantly gas-cleaned with biogas, the membrane surface velocity of the membrane separation device 4 is ensured and the solid matter is attached to the membrane surface. Blockage can be prevented and the life of the membrane can be significantly increased.

Fourth Embodiment Next, a fourth embodiment of the present invention according to FIG. 4 will be described.

In FIG. 4, the same parts as those of the first embodiment shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 4, the methane fermentation reactor 2
A membrane separation device 4 is installed inside, and the treated water subjected to membrane separation by the membrane separation device 4 is taken out of the system via a drawing pump 5. A part of the supernatant water of the methane fermentation reactor 2 is guided to the lower part of the methane fermentation reactor 2 by the second circulation line 10 a having the second circulation pump 10.

In FIG. 4, a part of the supernatant water of the methane fermentation reactor 2 is guided to the lower part of the methane fermentation reactor 2 by the second circulation line 10a having the second circulation pump 10. As a result, the rising flow velocity inside the methane fermentation reactor 2 can be increased, and the membrane surface flow velocity of the membrane separation device 4 is increased.

Here, the place for returning the circulating water from the second circulation line 10a is not limited to the lower part of the reactor 2,
The circulation runner 10a may be connected near the lower part of the membrane separation device 4 of the reactor 2.

According to the present embodiment, the rising flow velocity inside the methane fermentation reactor 2 can be increased, so that the membrane surface flow velocity of the membrane separation device 4 can be increased. As a result, the life of the film could be significantly increased. Further, since the rising flow velocity in the granule 3 can be increased, it is possible to prevent deterioration of the quality of treated water due to a short circuit.

Fifth Embodiment Next, a fifth embodiment of the present invention according to FIG. 5 will be described.

In FIG. 5, the same parts as those of the first embodiment shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 5, the methane fermentation reactor 2
A membrane separation device 4 is installed inside, and the treated water subjected to membrane separation by the membrane separation device 4 is taken out of the system via a drawing pump 5. Further, in the reactor 2, a gas collecting device 11 is provided below the membrane separation device 4, and the granules 3
The biogas generated by is introduced into the membrane separation device 4 via the gas collector 11.

In FIG. 5, the biogas generated by the granules 3 in the reactor 2 is guided to the lower part of the membrane separation device 4 via the gas collector 11. As a result, the membrane separation device 4 is always gas-washed with the biogas, so that it is possible to secure the flow velocity on the membrane surface of the membrane separation device 4 and prevent clogging due to adhesion of solid matter to the membrane surface.

According to the present embodiment, since the membrane separation device 4 can be constantly gas-washed with biogas, it is possible to secure a flow velocity on the membrane surface and prevent clogging due to the adhesion of solid matter to the membrane surface. The life of the can be greatly increased. Further, since it is not necessary to install a blower or the like outside the reactor 2, it becomes possible to reduce the power cost and prevent gas leakage from the gas pipe.

Sixth Embodiment Next, a sixth embodiment of the present invention according to FIG. 6 will be described.

In FIG. 6, the same parts as those of the first embodiment shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 6, the methane fermentation reactor 2
A treated water tank 12 is connected to the upper part of the tank via a gas collector 11. The membrane separation device 4 is installed inside the treated water tank 12, and the treated water membrane-separated by the membrane separation device 4 is taken out of the system via the drawing pump 5.

The biogas generated by the granules 3 is introduced into the treated water tank 12 through the gas collector 11 together with the treated water containing the granules 3. The treated water tank 12 and the reactor 2 are connected by a return line 13, and a part of the treated water that has risen in the treated water tank 12 together with the biogas is returned to the lower part of the reactor 2 through the return line 13 together with the granules 3.

In FIG. 6, the biogas generated by the granules 3 in the reactor 2 is guided to the treated water tank 12 via the gas collector 11. At this time, the treated water containing the granules 3 is also treated by the gas hold-up action.
Transferred to 2. In the treated water tank 12, the treated water is filtered by the membrane separation device 4 and the drawing pump 5 and discharged to the outside of the system.

The inside of the treated water tank 12 is constantly mixed with the treated water containing the granules 3 transferred by biogas and gas hold-up, so that the membrane surface velocity of the membrane separation device 4 is secured and solid matters on the membrane surface are secured. It is possible to prevent blockage due to adhesion of

The treated water containing the granules 3 in the treated water tank 12 is returned to the lower part of the reactor 2 via the return line 13.

According to the present embodiment, the inside of the treated water tank 13 is constantly stirred by the biogas, so that the membrane separation device 4
It is possible to secure the flow velocity on the membrane surface and prevent clogging due to adhesion of solid matter to the membrane surface, and it is possible to significantly increase the life of the membrane. Further, since it is not necessary to install a blower or the like outside the reactor 2, it becomes possible to reduce the power cost and prevent gas leakage from the gas pipe.

Seventh Embodiment Next, a seventh embodiment of the present invention according to FIG. 7 will be described.

In FIG. 7, the same parts as those of the sixth embodiment shown in FIG. 6 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 7, the methane fermentation reactor 2
A membrane separation device 4 is installed inside the treated water tank 12 provided at the upper part of the above, and the treated water subjected to membrane separation by the membrane separation device 4 is taken out of the system via a drawing pump 5.
The biogas generated by the granules 3 is guided to the treated water tank 12 via the gas collector 11. A part of the treated water containing the granules 3 that has risen in the treated water tank 12 together with the biogas is returned to the lower part of the methane fermentation reactor 2 via the return line 13.

Below the gas collector 11 of the reactor 2, one end of a gas line 15a, one end of which is connected to the nitrogen cylinder 15, is connected. An opening / closing valve 21 is provided in the gas line 15a. Further, a gas meter 14 is provided in the biogas pipe 20, and the opening / closing valve 21 is controlled by the control device 22 based on a signal from the gas meter 14.

In FIG. 7, the biogas generated by the granules 3 in the reactor 2 is introduced into the treated water tank 12 via the gas collector 11. At this time, the treated water is also transferred to the treated water tank 12 by the gas hold-up action. The treated water in the treated water tank 12 is filtered under reduced pressure by the membrane separation device 4 and the drawing pump 5 and discharged to the outside of the system.

As described above, the inside of the treated water tank 12 is constantly mixed with the biogas and the water to be treated transferred by the gas hold-up, so that the membrane surface velocity of the membrane separation device 4 is secured and solid matter on the membrane surface is secured. Blockage due to adhesion can be prevented.

The treated water containing the granules 3 in the membrane separation device 4 is returned to the lower part of the reactor 2 via the return line 13.

When the amount of biogas generated is insufficient at the start-up, the amount of gas generated is measured by the gas meter 14, the on-off valve 21 is controlled by the controller 22, and the shortage is supplied from the nitrogen cylinder 15 to the gas line 15a. It is supplemented by nitrogen supplied via.

According to the present embodiment, the reactor 2 is agitated by the nitrogen gas even when the activity of the methane bacteria is inhibited at the initial stage of startup or for some reason and the gas generation amount in the reactor 2 is reduced. Therefore, the membrane separation device 4
It is possible to secure the flow velocity on the membrane surface and prevent clogging due to adhesion of solid matter to the membrane surface, and it is possible to significantly increase the life of the membrane.

Further, since it is not necessary to install a blower or the like outside the reactor 2, it becomes possible to reduce the power cost and prevent gas leakage from the gas pipe.

Eighth Embodiment Next, an eighth embodiment of the present invention according to FIG. 8 will be described.

In FIG. 8, the same parts as those in the first embodiment shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 8, the methane fermentation reactor 2
A membrane separation device 4 is installed inside, and the treated water subjected to membrane separation by the membrane separation device 4 is taken out of the system via a drawing pump 5. Level sensor 16 in reactor 2
When the water level of the methane fermentation reactor 2 is detected by the level sensor 16 and the water level of the methane fermentation reactor 2 is increased by the control device 23, the extraction pump 5
It controls the number of rotations of.

In FIG. 8, the water level of the methane fermentation reactor 2 is detected by the level sensor 16, the filtration resistance of the membrane surface of the membrane separation device 4 is judged by the increase and decrease of the water level, and the extraction pump 5
It is possible to keep the water level of the reactor 2 constant by controlling the rotation speed of the reactor.

As described above, according to the present embodiment, since the water level of the methane fermentation reactor 2 can be controlled to be constant, the amount of treated water drawn out is reduced due to the clogging of the membrane surface of the membrane separation device 4, or the treated water is removed. It is possible to prevent a decrease in the water level of the reactor 2 due to excessive drawing. Therefore, a stable amount of treated water can be obtained.

Ninth Embodiment Next, a ninth embodiment of the present invention according to FIG. 9 will be described.

In FIG. 9, those parts which are the same as those of the third embodiment shown in FIG. 3 are designated by the same reference numerals, and a detailed description thereof will be omitted.

As shown in FIG. 9, the methane fermentation reactor 2
A membrane separation device 4 is installed inside, and the treated water subjected to membrane separation by the membrane separation device 4 is taken out of the system via a drawing pump 5.

A part of the biogas generated from the methane fermentation reactor 2 is a biogas circulation line 8 having a blower 8.
It is guided to the air diffuser 9 installed under the membrane separation device 4 via a, and the membrane surface of the membrane separation device 4 is cleaned with gas. Further, the reactor 2 is provided with a level sensor 16 for detecting the water position in the reactor 2, and the level sensor 16 detects the water level of the reactor 2. When the water level in the reactor 2 rises, the control device 24 controls the rotation speed of the blower 8 by the signal from the level sensor 16.

In FIG. 9, the water level of the methane fermentation reactor 2 is detected by the level sensor 16. Control device 24
Determines the closed state of the membrane surface of the membrane separation device 4 by increasing / decreasing the water level of the reactor 2 and controlling the rotation speed of the blower 8 to adjust the amount of biogas from the air diffuser 9 to properly wash the membrane surface. To do.

According to the present embodiment, it is possible to judge the blockage state of the membrane surface of the membrane separation device 4 based on the water level of the reactor 2, so that it is possible to prevent excessive gas cleaning with biogas and to improve the efficiency of power. Available.

Tenth Embodiment Next, a tenth embodiment of the present invention according to FIG. 10 will be described.

In FIG. 10, the same parts as those of the first embodiment shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 10, a membrane separation device 4 is installed inside the methane fermentation reactor 2, and the treated water separated by the membrane separation device 4 is discharged to the outside of the system via a drawing pump 5. Taken out. A level sensor 16 for detecting the water level in the reactor 2 is provided in the reactor 2, and an air diffuser 9 is provided below the membrane separation device 4 in the reactor 2. Further, the other end of the gas line 15 a, one end of which is connected to the nitrogen cylinder 15, is connected to the air diffusing pipe 9.

An on-off valve 17 is attached to the gas line 15a, and this on-off valve 17 is a level sensor 16
It is controlled by the control device 25 based on the signal from.

In FIG. 10, the water level of the methane fermentation reactor 2 is detected by the level sensor 16, and the controller 25
The occlusion of the membrane surface of the membrane separation device 4 is determined based on the increase / decrease in the water level. The control device 25 then opens and closes the on-off valve 17, and the nitrogen gas from the nitrogen cylinder 15 causes the membrane separation device 4 to operate.
The membrane surface of the membrane separation device 4 is washed through the air diffuser 9 provided in the lower part of the.

According to the present embodiment, since the controller 25 can determine the clogging of the membrane surface by the water level of the methane fermentation reactor 2, excessive gas cleaning with nitrogen gas can be prevented, and the amount of nitrogen gas used can be reduced. Can be reduced.

Eleventh Embodiment Next, an eleventh embodiment of the present invention according to FIG. 11 will be described.

In FIG. 11, the same parts as those of the first embodiment shown in FIG. 12 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 10, the inside of the methane fermentation reactor 2 is divided into a plurality of regions by a partition plate 18, and the membrane separation device 4 is installed in each of the partitioned regions. The treated water that has been subjected to membrane separation by each membrane separation device 4 is taken out of the system via a drawing pump 5. A manhole (not shown) of a size that allows the membrane separation device 4 installed at each location to be taken in and out is provided above the area partitioned by the partition plate 18.

In FIG. 11, since the membrane separation devices 4 are located in the areas partitioned by the partition plates 18, the membrane separation action can be efficiently performed. Further, a manhole through which the membrane separation device 4 can be put in and taken out is provided above each of them. Therefore, when the membrane of the membrane separation device 4 is maintained or replaced, the membrane can be replaced by opening only the manhole in the partitioned area without opening the lid of the entire reactor 2.

[0101]

As described above, according to the present invention, a large amount of granules can be reliably held in the reactor,
This enables efficient operation with a high load.

[Brief description of drawings]

FIG. 1 is a structural diagram showing a first embodiment of an anaerobic water treatment device according to the present invention.

FIG. 2 is a structural diagram showing a second embodiment of an anaerobic water treatment device according to the present invention.

FIG. 3 is a structural diagram showing a third embodiment of the anaerobic water treatment device according to the present invention.

FIG. 4 is a structural diagram showing a fourth embodiment of the anaerobic water treatment device according to the present invention.

FIG. 5 is a structural diagram showing a fifth embodiment of the anaerobic water treatment device according to the present invention.

FIG. 6 is a structural diagram showing a sixth embodiment of the anaerobic water treatment device according to the present invention.

FIG. 7 is a structural diagram showing a seventh embodiment of the anaerobic water treatment system according to the present invention.

FIG. 8 is a structural diagram showing an anaerobic water treatment device according to an eighth embodiment of the present invention.

FIG. 9 is a structural diagram showing a ninth embodiment of the anaerobic water treatment device according to the present invention.

FIG. 10 is a structural diagram showing a tenth embodiment of the anaerobic water treatment system according to the present invention.

FIG. 11 is a structural diagram showing an eleventh embodiment of an anaerobic water treatment device according to the present invention.

FIG. 12 is a diagram showing a typical treatment flow of a conventional anaerobic water treatment device.

[Explanation of symbols]

1 Raw water pump 2 Methane fermentation reactor 3 granules 4 Membrane separation device 5 Drawing pump 6 circulation tanks 7 Circulation pump 7a First circulation line 8 blowers 8a Biogas circulation line 9 Air diffuser 10 Second circulation pump 10a Second circulation line 11 Gas collector 12 treated water tank 13 Return line 14 gas meter 15 Nitrogen cylinder 15a gas line 16 level sensor 17 on-off valve 18 dividers 20 biogas piping 21 on-off valve 22,23,24,25 control device

Claims (11)

[Claims] 1. A reactor having granules, which treats wastewater with the granules to produce treated water, a membrane separator installed in the reactor for separating granules from the treated water, and a treatment from the membrane separator. An anaerobic water treatment device equipped with a drawing pump for drawing water. 2. A reactor having granules, which treats wastewater with the granules to produce treated water, a circulation tank for taking out the treated water in the reactor, and the treated water in the circulation tank is circulated to the lower part of the reactor. A first circulation line having a first circulation pump, a membrane separator installed in the circulation tank for separating granules from the treated water, and a drawing pump for drawing the treated water from the membrane separator. And anaerobic water treatment equipment. 3. An anaerobic water according to claim 1, wherein an air diffuser is provided in the lower part of the membrane separation device, and the reactor upper part and the air diffuser are connected by a biogas circulation line having a blower. Processing equipment. 4. The anaerobic water treatment system according to claim 1, further comprising a second circulation line having a second circulation pump for returning the treated water in the upper part of the reactor to the lower side of the membrane separation device. 5. The anaerobic water treatment device according to claim 1, further comprising a gas collecting device provided below the membrane separation device for cleaning the gas of the membrane separation device with biogas from the granules. 6. A reactor having granules, which treats wastewater with the granules to produce treated water, a treated water tank installed on the upper part of the reactor, and a granule separated from the treated water installed in the treated water tank. Membrane separation device, an extraction pump that draws the treated water out of the membrane separator, a gas collector that collects the treated water and biogas in the reactor and guides them to the treated water tank, and returns the treated water in the treated water tank to the reactor. An anaerobic water treatment device comprising a return line. 7. A gas line for introducing nitrogen gas and having an open / close valve is provided below the gas collector in the rear tank, and a gas meter for detecting the gas generation amount is provided in the treated water tank, and control is performed based on a signal from the gas meter. The anaerobic water treatment device according to claim 6, wherein the on-off valve is controlled by the device. 8. The anaerobic chamber according to claim 1, wherein the reactor is provided with a sensor for detecting the water level in the reactor, and the control unit controls the drawing pump based on a signal from the sensor. Water treatment equipment. 9. The anaerobic water treatment apparatus according to claim 3, wherein the reactor is provided with a sensor for detecting the water level in the reactor, and the blower is controlled by the control device based on a signal from the sensor. 10. An air diffusing pipe is provided in the lower part of the membrane separation device, a gas line for introducing nitrogen gas into the diffusing pipe and having an opening / closing valve is provided, and a sensor for detecting the water level in the reactor is provided in the reactor. The anaerobic water treatment system according to claim 1 or 2, wherein the control device controls the on-off valve based on the signal. 11. The anaerobic water treatment system according to claim 1, wherein a partition plate for dividing the inside of the reactor into a plurality of regions is provided, and a membrane separation device is provided in each region surrounded by the partition plate. apparatus.