JP7137901B2 - Sewage treatment equipment and sewage treatment method - Google Patents

Description

The present invention relates to a sewage treatment apparatus and a sewage treatment method.

Conventionally, a reaction tank for biologically treating sewage, a membrane separation device for removing solids from the sewage immersed in the reaction tank and biologically treated, and a membrane separation device installed at the bottom of the membrane separation device The biological treatment of sewage in the reaction tank is, for example, organic sludge containing microorganisms, that is, so-called activated sludge. It is carried out on the basis of the activated sludge method. Specifically, in the activated sludge process, a nitrification reaction is performed in the presence of oxygen (aerobic conditions) to convert ammonia into nitrous acid or nitric acid.

By the way, in order to treat sewage to obtain clear treated water, it is necessary to perform a denitrification reaction to convert nitrous acid and nitric acid converted from ammonia into nitrogen. Unlike the nitrification reaction which is carried out in the presence of oxygen (aerobic condition), the denitrification reaction must be carried out in the absence of oxygen. The denitrification reaction may be performed in a reaction tank different from the reaction tank in which the nitrification reaction is performed. A sewage treatment apparatus has been proposed (see, for example, Patent Document 1).

FIG. 7 is a diagram schematically showing a conventional sewage treatment apparatus. The sewage treatment apparatus of FIG. 7 includes a reaction tank 1 for performing a nitrification reaction under an aerobic condition and a denitrification reaction under an anoxic condition, and a raw water tank 9 for supplying sewage to the reaction tank 1. 1 has a partition plate 7 for partitioning the inside of the reaction tank 1 into a plurality of compartments. Specifically, the reaction tank 1 is partitioned into a sewage area A surrounded by a partition plate 7 and a sewage area B surrounded by the partition plate 7 and the inner wall of the reaction tank 1. It has a trachea 4. In addition, the reaction tank 1 has a sewage supply start water level LWL (Low water level) for starting the supply of sewage from the raw water tank 9 and a sewage supply stop water level HWL for stopping the supply of sewage from the raw water tank 9. (High water level), and the upper end of the partition plate 7 is located between the sewage supply start water level LWL and the sewage supply stop water level HWL.

In the sewage treatment apparatus of FIG. 7, when the water level in the reaction tank 1 reaches the sewage supply start water level LWL, the supply of sewage from the raw water tank 9 is started, and when the water level reaches the sewage supply stop water level HWL, the sewage is discharged from the raw water tank 9. is set so that the supply of water is stopped and the sewage level is configured to vary. As a result, the water level of the sewage is set at a position higher than the upper end of the partition plate 7 (hereinafter referred to as "the sewage overflow position") and a position lower than the upper end of the partition plate 7 (hereafter referred to as the "wastewater non-overflow position"). ) and back and forth.

FIG. 8 is a diagram schematically showing the flow of sewage when the water level of sewage in the reaction tank 1 in FIG. 7 is at the sewage overflow position.

When the sewage water level is at the sewage overflow position, sewage overflows the upper end of the partition plate 7 due to the air supplied from the air diffuser 4 to the membrane separation device 2, and the circulation flow circulates around the partition plate 7. is formed. Due to this circulating flow, nitric acid and the like in the sewage area A move to the sewage area B, and most of the air in the sewage area A is released outside the reaction tank 1 without moving to the sewage area B. That is, when the circulation flow is formed, the nitrification reaction that converts ammonia into nitrite and nitric acid proceeds in the presence of oxygen in the sewage area A, and in the sewage area B, the nitrite and nitrite that migrate from the sewage area on the circulation flow. A denitrification reaction that converts nitric acid to nitrogen proceeds.

On the other hand, when the sewage water level is at the sewage non-overflow position, the flow of sewage is divided between the sewage region A and the sewage region B, so even if the air diffuser 4 supplies air to the membrane separation device 2 , no circulation flow circulating around the partition plate 7 is formed. That is, in the sewage area A, the nitrification reaction that converts ammonia into nitrite and nitric acid proceeds in the presence of oxygen, and in the sewage area B, nitrite and nitric acid that have moved from the sewage area A before the flow of sewage is cut off are converted into nitrogen. The denitrification reaction that converts to progresses.

Japanese Patent Application Laid-Open No. 2004-261711

However, turbulent flow 30 occurs in part of the sewage that overflows the upper end of the partition plate 7 and moves to the sewage area B (FIG. 9). That is, among the sewage existing in the sewage area B, sewage that does not move from the sewage area B through the lower end of the partition plate 7 to the sewage area A may exist as a circulating flow.

Therefore, even if sewage overflows the upper end of the partition plate 7 and a circulation flow circulating around the partition plate 7 is formed, some sewage does not circulate around the partition plate 7 due to the influence of the turbulent flow 30 . As a result, the nitrification reaction and the denitrification reaction do not proceed as expected, and there is a problem that the sewage treatment cannot be stably performed.

An object of the present invention is to provide a sewage treatment apparatus and a sewage treatment method that can stably carry out sewage treatment.

In order to achieve the above object, the sewage treatment apparatus of the present invention comprises a membrane separation device for separating contaminants contained in the sewage, and air bubbles in the membrane separation device inside a reaction tank for treating sewage. In a sewage treatment apparatus comprising an air diffuser for supplying and a partition plate for partitioning the inside of the reaction tank into a plurality of areas, the partition plate divides the inside of the reaction tank into nitrous acid or nitric acid to remove ammonia contained in the sewage. and a second region where the denitrification reaction of converting the nitrous acid or nitric acid to nitrogen proceeds in the absence of oxygen. It has a contact surface with which sewage contacts, the contact surface has a rectangular flow control plate protruding toward the second region, and the longitudinal direction of the flow control plate extends along the vertical direction. and
In order to achieve the above object, the sewage treatment apparatus of the present invention comprises a membrane separation device for separating contaminants contained in the sewage, and air bubbles in the membrane separation device inside a reaction tank for treating sewage. A sewage treatment apparatus comprising an air diffuser to supply air and a partition plate that partitions the interior of the reaction tank into a plurality of regions, wherein the partition plate divides the interior of the reaction tank into a first region where the air diffuser is arranged , and a second region other than the first region, and have a contact surface with which the sewage in the second region contacts, the contact surface projecting to the second region. A plate is provided, and the flow control plate is spirally fixed to the contact surface.

In order to achieve the above object, the sewage treatment method of the present invention comprises a membrane separation device for separating contaminants contained in the sewage, and air bubbles in the membrane separation device inside a reaction tank for treating sewage. and a partition plate that partitions the inside of the reaction tank into a plurality of areas, the partition plate divides the inside of the reaction tank into nitrite or nitric acid to convert ammonia contained in the sewage into nitrous acid or nitric acid. A first zone where the reaction proceeds and a second zone where the denitrifying reaction that converts the nitrous acid or the nitric acid into nitrogen in the absence of oxygen is partitioned, and in contact with the sewage in the second zone. A sewage treatment apparatus having a contact surface, the contact surface having a rectangular flow control plate protruding toward the second region, and the longitudinal direction of the flow control plate extending along the vertical direction . The above sewage treatment method is characterized by comprising an overflow step in which the sewage flows over the partition plate, and a flow control step in which the sewage flow over the partition plate flows along the flow control plate.
In order to achieve the above object, the sewage treatment method of the present invention comprises a membrane separation device for separating contaminants contained in the sewage, and air bubbles in the membrane separation device inside a reaction tank for treating sewage. and a partition plate that partitions the interior of the reaction vessel into a plurality of regions, the partition plate dividing the interior of the reaction vessel into a first region where the air diffusion pipe is arranged and the first region where the air diffuser is arranged. and a second region other than the region, and has a contact surface with which the sewage in the second region comes into contact, and the contact surface has a flow control plate that protrudes with respect to the second region a sewage treatment method using a sewage treatment apparatus in which the flow control plate is spirally fixed to the contact surface, wherein the sewage overflows the partition plate; and a restricting step for flowing along the restricting plate.

ADVANTAGE OF THE INVENTION According to this invention, sewage treatment can be performed stably.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows schematically the sewage treatment apparatus which concerns on embodiment of this invention. FIG. 2 is a perspective view schematically showing the periphery of a partition plate of the reaction vessel in FIG. 1; 2 is a top view of the sewage treatment apparatus of FIG. 1; FIG. FIG. 3 is a perspective view schematically showing a first modification of the flow control plate in FIG. 2; FIG. 3 is a perspective view schematically showing a second modification of the flow control plate in FIG. 2; FIG. 6 is a top view of a reaction tank provided with the membrane separation device, partition plate and flow control plate in FIG. 5; It is a figure which shows the conventional sewage treatment apparatus roughly. FIG. 8 is a side view schematically showing the flow of sewage in the reaction tank in FIG. 7; FIG. 8 is a perspective view schematically showing the flow of sewage in the reaction tank in FIG. 7;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram schematically showing a sewage treatment apparatus according to an embodiment of the invention.

The sewage treatment apparatus of FIG. 1 includes a single tank type reaction tank 1 for treating sewage. and a partition plate 7 that partitions the interior of the reactor 1 into a plurality of regions. The membrane separation device 2 is connected to a suction pump 3 outside the reactor 1 . When the suction pump 3 is driven, the biologically treated sewage is filtered by the membrane separator 2 and the filtered water is taken out of the reaction tank 1 .

The diffuser pipe 4 is installed in the lower part of the membrane separation device 2 and connected to a blower 5 outside the reaction vessel 1 , and the blower 5 supplies air to the diffuser pipe 4 . Since the membrane separation device 2 filters sewage, sludge substances and the like in the sewage adhere to the membrane surface of the membrane separation device 2. The membrane separation device 2 becomes clogged and cannot properly filter sewage. Therefore, the diffuser pipe 4 supplies air to the membrane surface of the membrane separator 2 and prevents sludge substances and the like from adhering to the membrane surface of the membrane separator 2 .

The reaction tank 1 is connected via a raw water pump 8 to a raw water tank (not shown) that stores sewage. When the raw water pump 8 is driven, sewage to be treated is supplied from the raw water tank to the reaction tank 1 . The reaction vessel 1 is composed of a bottom portion 1a and a vessel wall 1b standing from the edge of the bottom portion 1a.

2 is a perspective view schematically showing the periphery of the partition plate 7 of the reaction tank 1 in FIG. 1, and FIG. 3 is a top view of the sewage treatment apparatus in FIG.

The partition plate 7 in FIGS. 2 and 3 is composed of four rectangular plate members, and the two partition plates 7 extend from the bottom 1a of the reaction tank 1 to the water surface of the sewage filling the reaction tank 1 in the longitudinal direction. (hereinafter referred to as “vertical direction”) and are opposed to each other via the membrane separation device 2 . The other two partition plates 7 have their longitudinal directions aligned in a direction perpendicular to the vertical direction (hereinafter referred to as "lateral direction") and are opposed to each other with the membrane separation device 2 interposed therebetween. Each partition plate 7 is connected to the adjacent partition plate 7 so as to be perpendicular to each other, is arranged so as to surround the membrane separator 2 and the air diffuser 4, and is arranged apart from the bottom portion 1a of the reaction vessel 1. By arranging the partition plate 7 in this way, the interior of the reaction vessel 1 is divided into an internal region 11 (first region) surrounded by the partition plate 7 and in which the diffuser pipe 4 is arranged, and an area other than the internal region 11 It is partitioned into an external area 12 (second area).

When the water level of the sewage in the reaction tank 1 is at the sewage overflow position, air is supplied from the air diffuser 4 to the membrane separation device 2, so that the sewage overflows the upper end of the partition plate 7 from the internal region 11 and is partitioned. There is a transition to the outer region 12 outside the plate 7 . After that, the sewage descends in the outer area 12 and returns to the inner area 11 of the partition plate 7 via the area below the partition plate 7 . That is, when the sewage water level is at the sewage overflow position and the sewage overflows the partition plate 7, a circulation flow circulating around the partition plate 7 is formed. When the circulation flow is formed, nitric acid and the like in the inner region 11 move to the outer region 12, but most of the air supplied from the air diffuser 4 does not move to the outer region 12 via the inner region 11 and reacts. It is discharged outside the tank 1 . That is, when the circulation flow is formed, the nitrification reaction that converts ammonia into nitrite and nitric acid proceeds in the inner region 11 in the presence of oxygen, and the nitrite and nitrite that migrate from the sewage region along the circulation flow progress in the outer region 12. A denitrification reaction that converts nitric acid to nitrogen proceeds.

The partition plate 7 has a contact surface 7a with which dirty water present in the outer region 12 contacts, and the contact surface 7a has a baffle plate 10 projecting with respect to the outer region 12 . The flow control plate 10 is a rectangular plate-like member, and is fixed to the contact surface 7a by, for example, welding, bolts, double-sided tape, or an adhesive so that the longitudinal direction of the flow control plate 10 is aligned with the vertical direction. . In this embodiment, the flow control plate 10 is fixed to the contact surface 7a so as to be perpendicular to both the bottom portion 1a of the reaction vessel 1 and the partition plate 7 to which it is fixed. Specifically, two flow control plates 10 are fixed so as to protrude from both ends of the partition plate 7 in the horizontal direction. Among the partition plates 7, the partition plate 7 whose longitudinal direction and lateral direction are aligned has three flow control plates 10 fixed at equal intervals so as to protrude from both ends in the lateral direction and the center thereof. .

The upper end portion of each flow control plate 10 is installed so as to be at approximately the same position as the upper end portion of the partition plate 7 . In addition, the lower end of each flow control plate 10 is placed apart from the bottom 1a of the reaction tank 1 so as to be positioned substantially at the same position as the lower end of the partition plate 7 (FIG. 1). The vertical length of the flow control plate 10 is substantially the same as the vertical length of the partition plate 7 . In addition, the thickness of the flow control plate 10 may be any thickness as long as it has the strength to withstand the flow of sewage.

In addition, in the present embodiment, two or three flow control plates 10 are fixed to each partition plate 7, but the number of flow control plates 10 fixed to each partition plate 7 and the number of flow control plates 10 The interval may be appropriately determined according to the size of the partition plate 7 and the size of the reaction vessel 1 .

Furthermore, in the present embodiment, the flow control plate 10 is fixed so as to be perpendicular to the bottom 1a of the reaction vessel 1 and the partition plate 7, respectively. may be fixed as

In addition, in the present embodiment, the case where the partition plate 7 surrounds the entire circumference of the membrane separation device 2 was described, but the partition plate 7 and the tank wall 1b of the reaction tank 1 allow the circumference of the membrane separation device 2 to may surround the Specifically, the membrane separation device 2 is surrounded by two opposing tank walls 1b of the reaction tank 1 and two rectangular partition plates 7, or three tank walls 1b of the reaction tank 1 and one rectangular partition plate 7 are enclosed. The membrane separation device 2 may be surrounded by a shaped partition plate 7 . Moreover, when the reaction vessel 1 is large, a plurality of internal regions 11 in which the air diffusion pipes 4 are arranged may be provided in order to increase the throughput per unit time.

Further, the sewage treatment apparatus of this embodiment may have water level control means for adjusting the water level in the reaction tank 1 . As the water level control means, for example, there is a liquid level sensor for checking the water level in the reaction tank 1, that is, the position of the liquid surface. When the liquid level sensor detects the level of sewage, the raw water pump 8 automatically controls the amount of raw water supplied to the reaction tank 1 .

Next, a sewage treatment method performed by a sewage treatment apparatus including a membrane separator 2, an air diffuser 4, and a partition plate 7 inside the reaction tank 1 will be described.

As described above, the sewage treatment apparatus of this embodiment includes the membrane separator 2 , the air diffuser 4 , and the partition plate 7 inside the reaction tank 1 . The membrane separation device 2 is connected to a suction pump 3 outside the reaction vessel 1, and the air diffuser 4 is connected to a blower 5 outside the reaction vessel 1 (Fig. 1).

The partition plate 7 surrounds the lateral periphery of the membrane separation device 2 and partitions the interior of the reaction vessel 1 into an internal region 11 in which the diffuser pipe 4 is arranged and an external region 12 other than the internal region 11 . The partition plate 7 has a contact surface 7a with which sewage existing in an external area 12 (outside the partition plate 7) contacts, and the contact surface 7a has a plurality of flow control plates 10 protruding with respect to the external area 12. . The flow control plate 10 is fixed so as to be perpendicular to the bottom surface of the reaction vessel 1 and the partition plate 7 . The reaction tank 1 contains activated sludge containing microorganisms, and the microorganisms decompose organic matter in the sewage.

When the blower 5 is driven, bubbly air is supplied from the diffuser pipe 4 installed at the bottom of the membrane separator 2 . Sewage supplied by the raw water pump 8 is treated in the reaction tank 1 . When the suction pump 3 is driven, the sewage that has been biologically treated by the membrane separation device 2 is filtered, and the filtered water is sucked by the suction pump 3 and taken out of the reaction tank 1 . At this time, the air supplied from the diffuser pipe 4 to the membrane separation device 2 collides with the membrane surface of the membrane separation device 2 to prevent sludge substances and the like from adhering to the membrane surface.

In the reaction vessel 1, a state in which the water level is higher than the upper end of the partition plate 7 (hereinafter referred to as "overflow state") and a state in which the water level is lower than the upper end of the partition plate 7 are alternately created.

In this embodiment, when the sewage is in an overflow state, the sewage upward flow formed in the inner region 11 by the air from the air diffuser 4 overflows the upper end of the partition plate 7 and overflows into the outer region 12. (overflow step). The sewage overflow speed in the overflow step can be adjusted by changing the air volume supplied from the blower 5 to the diffuser pipe 4 .

The sewage overflowing the external area 12 has its flow path regulated by the flow control plate 10, and descends along the flow control plate 10 in the external region 12 (flow control step). In the case of the flow control plate 10 in FIG. 2, the flow of sewage in the outer region 12 is restricted in the vertical direction. Therefore, when the sewage descends in the outer region 12, a turbulent flow is generated, and even if it is affected by the turbulent flow, it descends in the outer region 12 without diffusing, and flows through the region below the partition plate 7. Afterwards, it returns to the inner region 11 and a circulation flow is formed.

That is, according to this embodiment, when the sewage is in an overflow state, the sewage existing in the external area 12 (outside the partition plate 7) generates losses such as dissipation of transfer energy due to turbulent flow. Since it descends without stopping and then returns to the inner region 11, the vigor of the circulating flow increases. As a result, the entire reaction tank 1 is affected by the circulation flow, most of the wastewater is affected by the circulation flow in the external region 12, and the nitrification reaction in the internal region 11 and the denitrification reaction in the external region 12 are assumed. go through the street.

In addition, since the circulation flow affects the entire reaction tank 1, there is no stagnation, uneven distribution, or sedimentation of sludge in the reaction tank 1, and the distribution of the activated sludge concentration and dissolved oxygen concentration in the reaction tank 1 is uniform. can do.

According to the sewage treatment apparatus of FIGS. 1 to 3, a reaction tank 1 for treating sewage is provided, and the reaction tank 1 has a membrane separator 2 and an air diffuser 4, and the membrane separator 2 and the air diffuser 4 It has a partition plate 7 arranged so as to surround it. The partition plate 7 divides the inside of the reaction vessel 1 into an internal area 11 where the air diffuser 4 is arranged and an external area 12 other than the internal area 11, and is separated from the bottom portion 1a of the reaction vessel 1. As a result, when the water level of the sewage in the reaction tank 1 is at the sewage overflow position, when air is supplied from the diffuser pipe 4 to the membrane separation device 2, a circulation flow is generated in which the sewage circulates around the partition plate 7. do.

At this time, the partition plate 7 has a contact surface 7a with which the sewage in the external area 12 contacts, and the contact surface 7a has the flow control plate 10 projecting to the external area 12, so that the upper end of the partition plate 7 is exceeded. The sewage overflowing to the external area 12 moves to the lower end of the partition plate 7 along the contact surface 7a and the flow control plate 10. As shown in FIG. As a result, a turbulent flow occurs while the sewage that has passed over the upper end of the partition plate 7 moves to the lower end of the partition plate 7, and a part of the sewage affected by the turbulent flow does not reach the lower end of the partition plate 7. Therefore, it is possible to prevent a reduction in the scale of the circulating flow of part of the sewage.

That is, the sewage overflowing the outer region 12 returns to the inner region 11 without causing loss such as dissipation of movement energy due to turbulent flow, thereby improving the vigor of the circulating flow. As a result, the entire reaction tank 1 is affected by the circulation flow, and most of the sewage in the external area 12 is affected by the circulation flow, so that the nitrification reaction in the internal area 11 and the denitrification reaction in the external area 12 are ensured. It is possible to proceed to the next step, and thus the sewage treatment can be stably performed.

In addition, since the circulation flow with increased momentum affects the entire reaction tank 1, the sludge does not stagnate in a part of the reaction tank 1, is unevenly distributed, or does not settle on the bottom 1a of the reaction tank 1. Since the distribution of activated sludge concentration and dissolved oxygen concentration in the reaction tank 1 becomes uniform, stable wastewater treatment can be performed.

FIG. 4 is a perspective view schematically showing a first modification of the flow restricting plate 10 in FIG. The flow control plate 40 shown in FIG. 4 is basically the same as the flow control plate 10 shown in FIG. It is different from the flow control plate 10 in FIG. Hereinafter, descriptions of duplicate configurations and actions will be omitted, and different configurations and actions will be described.

In FIG. 4, each flow control plate 40 is installed so that its lower end portion abuts against the bottom portion 1a of the reaction vessel 1. As shown in FIG. That is, the lower end of the flow control plate 40 in FIG. 4 extends to the bottom 1a of the reaction tank 1 than the lower end of the flow control plate 10 in FIG. Therefore, even in the area below the partition plate 7, when the sewage is in an overflow state, the flow path of the sewage is regulated, and the sewage moves to the inner area 11 without being diffused by turbulent flow. Therefore, by using the flow control plate 40 in FIG. 4, the loss of the wastewater transfer energy can be prevented in the vicinity of the lower end of the partition plate 7, so that the momentum of the circulating flow throughout the reaction tank 1 is further improved. and more stable sewage treatment.

FIG. 5 is a perspective view schematically showing a second modification of the flow control plate 10 in FIG. 2, and FIG. 2 is a top view of the reaction tank 1; FIG.

The restrictor plate 50 in FIGS. 5 and 6 is basically the same in configuration and function as the restrictor plate 10 in FIG. It differs from the flow control plate 10 in FIG. Hereinafter, descriptions of duplicate configurations and actions will be omitted, and different configurations and actions will be described.

5 and 6, a plurality of flow control plates 50 are connected one by one and fixed spirally to the contact surface 7a of the partition plate 7 with which the sewage in the external area 12 contacts.

The flow control plate 10 in FIGS. 2 and 4 regulates the flow of sewage overflowing from the inner region 11 to the outer region 12 in the vertical direction when the sewage is in an overflow state, and in the outer region 12 form a flow of On the other hand, the flow control plate 50 in FIG. form a flow.

Even if turbulence occurs, the sewage whose flow path is regulated by the flow control plate 50 spirally descends inside the external region 12 along the flow control plate 50 without being affected by the turbulence. After that, the sewage that has reached the lower end of the partition plate 7 returns to the inner region 11 through the region below the partition plate 7 to form a circulation flow.

A vortex is formed in the outer region 12 when the baffle plate 50 of FIG. 5 is fixed to the contact surface 7a. As a result, the sewage in the outer region 12 is affected by the swirling current and returns to the inner region 11 after being uniformly agitated. In addition, since the sludge is agitated with the swirling current and circulates in the reaction tank 1, it becomes difficult for the sludge to stay around the tank wall 1b in the bottom part 1a of the reaction tank 1, and it is possible to prevent the sludge from settling on the bottom part 1a of the reaction tank 1. . The number of flow control plates 50 fixed to the contact surface 7 a and the intervals between the flow control plates 10 may be appropriately determined according to the size of the partition plate 7 and the size of the reaction vessel 1 .

Although the present invention has been described using the above-described embodiments, the present invention is not limited to the above-described embodiments.

INDUSTRIAL APPLICABILITY The present invention can provide a sewage treatment apparatus and method that can stably carry out sewage treatment.

1 Reaction Tank 2 Membrane Separator 4 Air Diffuser 7 Partition Plate 7a Contact Surface 10, 40, 50 Control Plate 11 Internal Area 12 External Area

Claims (6)

A membrane separation device for separating contaminants contained in the sewage, an air diffuser for supplying air bubbles to the membrane separation device, and a plurality of regions inside the reaction vessel for treating sewage. In a sewage treatment device comprising a partition plate,
The partition plate divides the interior of the reaction tank into a first region where a nitrification reaction that converts ammonia contained in the sewage into nitrous acid or nitric acid proceeds, and a first region where the nitrous acid or nitric acid is converted into nitrogen in an oxygen-free state. It is divided into a second region where the denitrification reaction to be converted progresses , and has a contact surface with which the sewage in the second region comes into contact,
The contact surface has a rectangular flow control plate that protrudes with respect to the second region ,
A sewage treatment apparatus , wherein the longitudinal direction of the flow control plate is along the vertical direction . 2. The sewage treatment apparatus according to claim 1, wherein the flow control plate is perpendicular to the bottom surface of the reaction tank and the partition plate. 3. A sewage treatment apparatus according to claim 2, wherein said flow control plate is in contact with the bottom of said reaction tank. A membrane separation device for separating contaminants contained in the sewage, an air diffuser for supplying air bubbles to the membrane separation device, and a plurality of regions inside the reaction vessel for treating sewage. In a sewage treatment device comprising a partition plate,
The partition plate partitions the interior of the reaction tank into a first region where the air diffuser is arranged and a second region other than the first region, and the second region contacts sewage. having a contact surface,
The contact surface has a flow control plate projecting with respect to the second region,
The sewage treatment apparatus, wherein the flow control plate is spirally fixed to the contact surface. A membrane separation device for separating contaminants contained in the sewage, an air diffuser for supplying air bubbles to the membrane separation device, and a plurality of regions inside the reaction vessel for treating sewage. and a partition plate that divides the interior of the reaction tank into a first region where a nitrification reaction that converts ammonia contained in the sewage into nitrous acid or nitric acid proceeds, and a first region where the nitrification reaction proceeds in an oxygen-free state. It is partitioned into a second region where nitric acid or a denitrification reaction that converts the nitric acid into nitrogen proceeds , and has a contact surface with which the sewage in the second region contacts, the contact surface being the second region. In a sewage treatment method using a sewage treatment apparatus having a rectangular flow control plate projecting against the
an overflow step in which the sewage exceeds the partition plate;
and a regulating step in which sewage that has passed over the partition plate flows along the regulating plate . A membrane separation device for separating contaminants contained in the sewage, an air diffuser for supplying air bubbles to the membrane separation device, and a plurality of regions inside the reaction vessel for treating sewage. a partition plate that partitions the interior of the reaction vessel into a first region in which the air diffuser is arranged and a second region other than the first region; a contact surface with which sewage in the area of the contact surface contacts the second area, the contact surface having a flow control plate protruding toward the second area, the flow control plate being spirally fixed to the contact surface In the sewage treatment method using the sewage treatment equipment,
an overflow step in which the sewage exceeds the partition plate;
a restricting step in which sewage that has crossed the partition plate flows along the restricting plate;
A sewage treatment method characterized by having

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