JP7423414B2 - Carrier separation device, operating method of carrier separation device, multistage carrier separation device, and anaerobic treatment device - Google Patents

Description

The present invention relates to a carrier separation device, a method of operating a carrier separation device, a multistage carrier separation device, and an anaerobic treatment device, and particularly proposes a technology that contributes to improving the ability to treat treated water containing a carrier.

Anaerobic treatment is a method for treating wastewater containing organic matter (organic wastewater), in which organic wastewater is passed through a reaction tank that holds an abiotic carrier and is biologically treated by anaerobic microorganisms attached to the carrier. Treatment methods are widely used. In particular, in the anaerobic treatment method, high-load, high-speed treatment can be performed by allowing granule sludge or the above-mentioned carrier to exist in the reaction tank and allowing organic wastewater to flow upward.

By the way, in the method using a fluid non-living carrier, microorganisms adhere to the carrier and a biofilm is formed on the surface of the carrier, a reaction that generates gas progresses inside the biofilm, and the generated gas adheres to the carrier. As a result, there is a problem in that the apparent specific gravity of the carrier becomes small, the carrier floats in the reaction tank, and the carrier flows out together with the separated treated water. Such problems can be alleviated by using a carrier that has a high specific gravity and a high sedimentation rate. However, if a carrier has an excessively high specific gravity and an excessively high sedimentation rate, the contact efficiency with the water to be treated is poor and sufficient treatment efficiency cannot be obtained, and solid matter may accumulate in the sedimentary layer of the sedimented carrier. There is a problem that the flow path is clogged, and on the other hand, when using a carrier that does not have such problems, it is difficult to avoid the above-mentioned floating and outflow of the carrier due to the generated gas.

Japanese Patent Application Publication No. 2012-110820 Japanese Patent Application Publication No. 2014-237102 Japanese Patent Application Publication No. 2009-220096

To solve this problem, for example, in the devices described in Patent Documents 1 and 2, the carriers flowing out from the reaction tank are collected in another tank (processed water tank) outside the reaction tank, and the separated carriers are circulated there. A device has been proposed that allows the water to be returned to the reaction tank via piping or the like. This equipment requires additional equipment outside the reaction tank to treat the bubbles (methane gas) separated from the carrier in addition to the treated water tank, so the equipment has a large number of components as an organic wastewater treatment equipment. There are problems in that it is difficult to store, and the installation area becomes large, and it is not sufficient to easily separate solids from the treated water.

In addition, to solve the problem of solids such as carriers flowing out from the reaction tank together with the treated water, we installed a screen outside the reaction tank to separate the solids and the treated water, and collected the separated solids with a scraper for reaction. Another option is to return the water to the tank, but there is also the problem that, for example, a scraper that has come into contact with sulfide-containing water will be exposed to the air and corrode.
Another option is to install a screen in the reaction tank so that even if the solids try to flow out with the treated water, the screen will separate them, but the screen is likely to become clogged with solids during the treatment process in the reaction tank. To prevent this, a separate aeration power, for example, may be required.

In addition, Patent Document 3 states, ``In an apparatus for separating solids contained in an inflowing liquid, a separation tank, a partition plate that partitions the inside of the separation tank into an inflow chamber and an outflow chamber, and a screen provided on the partition plate. , comprising an inflow part formed in an inflow chamber and a discharge part formed in an outflow chamber, and the liquid flowing into the inflow chamber from the inflow part is reversed to form a vertical swirling flow in the inflow chamber. ``separation device'' has been proposed, characterized in that a guiding part is provided for the separation, and the screen is arranged along a side surface of the swirling flow that is formed. However, this device is intended to separate solids contained in wastewater flowing through sewer pipes and liquids flowing through wastewater treatment facilities in factories, etc., and is not used to separate carriers from treated water containing carriers. is not used.

Therefore, the present invention aims to prevent the carrier from clogging the screen by generating a swirling flow with the treated water containing the carrier, and to separate the carrier from the treated water containing the carrier. It is an object of the present invention to provide a device, a method for operating a carrier separation device, a multistage carrier separation device, and an anaerobic treatment device capable of efficiently treating wastewater.

The carrier separation device of the present invention includes:
It is formed of an outer tank, and a compartment including a curved swirling flow forming part and a side wall part for generating a swirling flow of the treated water containing carriers holding microorganisms housed inside the outer tank. an inner tank, and a separation tank comprising;
a screen that is disposed on the side wall on the side of the swirling flow and allows the treated water from which the carrier has been separated to pass from the inner tank to the outer tank;
an inflow section through which the treated water containing the carrier flows into the inner tank;
an outflow portion that allows the treated water from which the carrier has been separated to flow out from the outer tank;
It is characterized by having the following.

Further, the carrier separation device of the present invention includes:
a brush that cleans the surface of the screen by sliding;
a sliding mechanism that slides the brush laterally on the surface of the screen;
It is preferable to have a drive source that operates the sliding mechanism.

The method of operating a carrier separation device of the present invention is the method of operating the carrier separation device described above, comprising:
A swirling flow velocity of the swirling flow is 80 m/h or more, and a ratio of a permeation flow velocity of the treated water through the screen to the swirling flow velocity is 1 or less.

The multistage carrier separation device of the present invention is a multistage carrier separation device that can separate carriers holding microorganisms and impurities in treated water containing the carriers and impurities,
The multistage carrier separation device includes a first separation device and a second separation device,
The first separation device and the second separation device each include a separation tank including an outer tank and an inner tank, an inflow portion that allows treated water containing a carrier to flow into the inner tank, and an inlet that allows the treated water from which the carriers have been separated to flow into the inner tank. an outflow portion for causing outflow from the outer tank to the outside,
The outer tank accommodates the inner tank therein,
The inner tank is formed of a division part including a curved swirling flow forming part and a side wall part for generating a swirling flow of the treated water containing the carrier, and a screen provided on the side wall part,
The screen is disposed on the side of the swirling flow, and allows the treated water from which impurities or carriers have been separated to pass from the inner tank to the outer tank,
the outflow portion of the first separation device and the inflow portion of the second separation device are connected;
The screen of the first separation device has a larger opening than the screen of the second separation device.

The anaerobic treatment device of the present invention includes:
an acid fermenter that decomposes organic matter contained in the water to be treated to obtain acid-fermented water;
A reaction tank into which the acid fermentation treated water is introduced and subjected to anaerobic treatment with a carrier that retains microorganisms in the acid fermentation treated water to obtain treated water containing the carrier;
an inner tank formed of an outer tank and a division part containing a curved swirling flow forming part and a side wall part for generating a swirling flow of the treated water containing the carrier inside the outer tank; and a separation tank comprising;
a screen that is disposed on the side wall on the side of the swirling flow and allows the treated water from which the carrier has been separated to pass from the inner tank to the outer tank;
an inflow section through which the treated water containing the carrier flows into the inner tank;
an outflow portion that allows the treated water from which the carrier has been separated to flow out from the outer tank;
a connecting part that connects the reaction tank and a carrier discharge part that is provided at the bottom of the inner tank and discharges the carrier to the outside;
It is characterized by having the following.

According to the present invention, by generating a swirling flow in treated water containing a carrier, it is possible to prevent the carrier from clogging the screen and to separate the carrier easily from the treated water containing the carrier. It is possible to provide a device, a method for operating a carrier separation device, a multistage carrier separation device, and an anaerobic treatment device capable of efficiently treating wastewater.

FIG. 1 is a schematic diagram showing an anaerobic treatment device including a carrier separation device according to an embodiment of the present invention. FIG. 2 is a transparent perspective view schematically showing the carrier separation device of FIG. 1. FIG. FIG. 2 is a transparent perspective view schematically showing the carrier separation device of FIG. 1 with an inner tank removed. FIG. 2 is a transparent perspective view schematically showing an inner tank of the carrier separation device of FIG. 1. FIG. FIG. 2 is a perspective front view schematically showing the carrier separation device of FIG. 1. FIG. FIG. 2 is a perspective plan view schematically showing the carrier separation device of FIG. 1. FIG. FIG. 2 is a transparent perspective view schematically showing a state in which solids are separated from treated water using the carrier separation device of FIG. 1. FIG. FIG. 3 is a perspective plan view schematically showing a carrier separation device according to another embodiment of the present invention. 9 is a perspective front view schematically showing the carrier separation device of FIG. 8. FIG. FIG. 1 is a perspective front view schematically showing a multistage carrier separation device according to an embodiment of the present invention. (a) to (g) are diagrams schematically showing reaction vessels used as comparative examples.

Embodiments of the present invention will be described in detail below.
The carrier separation device 1 of this embodiment is a device that can be used, for example, in an anaerobic treatment device 4 as shown in FIG. 1, and is for separating carriers from treated water containing carriers.
Specifically, the anaerobic treatment device 4, which can be equipped with the carrier separation device 1 of the present embodiment, is used to treat organic wastewater containing organic matter, such as manufacturing wastewater from food factories, organic wastewater from chemical factories, and general sewage. This is a device that performs anaerobic treatment by bringing wastewater into contact with anaerobic microorganisms. Organic wastewater is passed through a reaction tank 41 that holds an abiotic carrier, and the anaerobic microorganisms attached to the carrier perform biological treatment. to be processed. The carrier separation device 1 of this embodiment separates the carriers from the treated water, since the treated water may contain carriers in the treated water treated in the reaction tank 41 in the anaerobic treatment device 4 as described above. It can be used to
Note that the carrier separation device 1 of this embodiment is not limited to application to the anaerobic treatment device 4 for anaerobic treatment as shown in FIG. The carrier separation device 1 of this embodiment can be used. Further, the anaerobic treatment device 4 will be explained in detail in the section of the anaerobic treatment device 4 of this embodiment described later.

As shown in FIG. 2, the carrier separation device 1 of this embodiment includes a separation tank 10 including an outer tank 11 and an inner tank 12, an inflow part 15 through which treated water containing carriers flows into the inner tank 12, It includes an outflow section 16 that allows the treated water from which the carriers have been separated to flow out from the outer tank 11. In addition, in the carrier separation device 1 of this embodiment, the outer tank 11 accommodates the inner tank 12 inside the outer tank 11, and the inner tank 12 is configured to swirl the treated water containing the carriers inside the inner tank 12. It is formed of a partition section 13 including a curved swirling flow forming section 132 and a side wall section 131 for generating a flow (see FIG. 7), and a screen 14 provided on the side wall section 131. It is arranged on the side of the flow, and allows the treated water from which the carriers have been separated to permeate from the inner tank 12 to the outer tank 11. Furthermore, as shown in FIG. 2, the carrier separation device 1 of this embodiment has a carrier discharge part 17 provided at the bottom of the inner tank 12 for discharging the carriers separated by the screen 14 from the inner tank 12 to the outside. can be provided.

The carrier separation device 1 of this embodiment has such a configuration, and by generating a swirling flow with the treated water containing carriers, it is possible to prevent the carriers from clogging the screen and to separate the treated water containing the carriers from clogging. The carrier can be easily separated.
Specifically, the carrier separation device 1 of this embodiment includes a separation tank 10 including an outer tank 11 and an inner tank 12, and a screen 14 that allows the treated water from which the carriers have been separated to pass from the inner tank 12 to the outer tank 11. Since this is provided, it is possible to separate the carriers in the treated water containing the carriers.
At this time, since the carrier separation device 1 of this embodiment has a curved swirling flow forming part 132 as the partition part 13 forming the inner tank 12, as shown in FIG. After the water flows in, a swirling flow of the treated water containing the carrier can be generated inside the inner tank 12. Since the screen 14 is placed on the side of the swirling flow in this carrier separation device 1, the carriers in the treated water are unevenly distributed inside and outside the swirling flow due to the centrifugal force when the treated water is swirled. , clogging of the screen 14 with carriers can be reduced, thereby making it easier for treated water to pass through the screen 14 with the carriers separated.
Note that by generating the swirling flow, it is also possible to prevent the carriers in the inner tank 12 from floating to the water surface.
Therefore, according to the carrier separation device 1 of the present embodiment, by generating a swirling flow with the treated water containing the carriers, it is possible to prevent the carriers from clogging the screen and to easily separate the carriers from the treated water containing the carriers. Can be separated. Further, as described above, the carrier separation device 1 of this embodiment has a simple and uncomplicated structure because it does not have many components, and can be a space-saving device, and maintenance such as cleaning can be easily performed. Can be done.
Furthermore, the carrier separation device 1 includes the carrier discharge part 17, so that the carriers contained in the treated water, that is, the carriers that did not permeate from the screen 14 to the outer tank 11 and were collected by the swirling flow, are removed from the treated water. It can be easily discharged from the device in a concentrated state.

Here, in the present embodiment, the treated water is wastewater obtained by, for example, anaerobically treating organic wastewater containing organic substances as described above (which may also contain waste liquid during treatment), such as methane. It is fermented water. The treated water contains suspended sludge and biofilms that have detached from the carrier, and if they are not discharged from the system, they will accumulate excessively in the reaction tank, reducing the fluidity of the carrier and potentially worsening the treatment. The treated water flowing into the carrier separation device 1 contains carriers that hold microorganisms, and the composition and concentration of the treated water are not particularly limited.

As the carrier, any carrier can be used without particular limitation as long as it can support microorganisms and allow the microorganisms to propagate on the surface of the carrier.
The shape of the carrier may be spherical, cylindrical, rectangular, hollow, etc., but it depends on the amount of microorganisms carried, the contact efficiency between the propagated microorganisms and organic wastewater, and the amount of carrier retained in the anaerobic reaction tank. In consideration of the above, a spherical shape is particularly preferable.
The dimensions of the carrier are preferably 0.1 mm or more and 20 mm or less in average value (median diameter d50 in the case of spherical particles, arithmetic mean value of the maximum dimension and minimum dimension in the case of other shapes), and 2 mm or more and 10 mm or less. The following are preferred.
The carrier is preferably a porous carrier having pores to which microorganisms easily adhere, and the pore diameter is preferably 1 μm or more and 100 μm or less, more preferably 5 μm or more and 50 μm or less.
In addition, from the viewpoint of good fluidization of the carrier in the anaerobic reaction tank, fresh water was flowed upward into a cylindrical column with a diameter of 80 mm filled with unused carrier at a linear velocity (LV) of 1 m/h or more and 20 m/h. The expansion rate when water is passed at a speed of LV2 m/h or more and 15 m/h or less is 105% or more and 150% or less (height of the carrier when water is passed relative to the height of the carrier at the time of injection) when water is passed at a speed of LV2 m/h or more and 15 m/h or less. It is preferably 110% or more and 130% or less.
The material for the carrier may be any material as long as anaerobic microorganisms can adhere thereto, but activated carbon, polyvinyl alcohol, ethylene glycol, and the like are particularly preferred since they satisfy the above-mentioned requirements.
The specific gravity of the carrier is preferably 1.001 or more and 1.5 or less, more preferably 1.01 or more and 1.5 or less. As described above, it is desirable that the specific gravity of the carrier is relatively high because it is easy to settle in the inner tank 12 of the carrier separator 1.

Next, the structure of the carrier separation device 1 of this embodiment will be explained in more detail.
The carrier separation apparatus 1 of this embodiment includes a separation tank 10 as shown in FIG. The separation tank 10 may be buried underground or may be installed above ground. The separation tank 10 can be shaped like a substantially rectangular parallelepiped box divided by a bottom part 111 and side parts 112, as shown in FIG. It has a space for introducing treated water containing water.
A depression 113 is formed in the bottom part 111, and has a shape that allows the carriers in the inner tank 12 to be easily led out to the carrier discharge part 17, as will be described later.
In the illustrated example, the side surface of the depression 113 is inclined so that the opening of the depression 113 widens from the bottom to the top in the vertical direction of the figure, and has a truncated cone shape (funnel-like shape). ).
Further, the separation tank 10 has an opening at the top, and the opening can be closed with a removable lid (not shown).
Although the separation tank 10 is formed in the shape of a rectangular parallelepiped in the illustrated example, it can have any shape.

Further, the separation tank 10 is preferably made of a material having corrosion resistance, and can be made of, for example, concrete, metal such as stainless steel, FRP (fiber reinforced plastic), or resin such as polyethylene. Alternatively, the separation tank 10 may have an outer frame made of concrete, and an inner surface made of the metal, FRP, or resin described above.

As shown in FIG. 2, the carrier separation device 1 includes an inlet 15 for allowing treated water containing carriers from a reaction tank to flow into the separation tank 10, specifically, into the inner tank 12. As shown in FIG. 3, the inflow portion 15 may be a pipe extending from the outside of the separation tank 10 and having an opening on the side 112 of the separation tank 10, It can also be a pipe that extends to the inside. In addition, the inflow portion 15 may be formed as a pipe extending from the outside of the separation tank 10 to near the opening of the separation tank 10 so that the treated water containing the carrier flows through the opening of the separation tank 10.
Although not shown, the inflow section 15 can include an inflow adjustment section such as a pump or a valve that can adjust the amount of inflow of treated water containing carriers.
The inflow portion 15 is preferably made of a material having corrosion resistance, and can be made of a metal such as stainless steel, for example.

As shown in FIG. 2, the carrier separation device 1 includes an outflow portion 16 for allowing the treated water from which the carriers have been separated to flow out from inside the separation tank 10, specifically, from the inside of the outer tank 11. As shown in FIG. 3, the outflow section 16 can be a pipe that has an opening in the side 112 of the separation tank 10 and extends to the outside of the separation tank 10; It can also be a pipe extending to the outside of the pipe. In addition, the outflow section 16 is a pipe extending from the inside of the inner tank 12 to the outside through the opening of the separation tank 10, and is formed so that the treated water from which the carrier has been separated is sucked by, for example, a pump and flows out to the outside. You can also do that.
Although not shown, the outflow section 16 can include an outflow adjustment section such as a pump or a valve that can adjust the outflow amount of the treated water containing the carrier.
The outflow portion 16 is preferably formed of a material having corrosion resistance, and can be formed of a metal such as stainless steel, for example.

As shown in FIG. 2, the carrier separation device 1 can include a carrier discharge part 17 provided at the bottom of the inner tank 12 for discharging the carriers separated by the screen 14 from the inner tank 12 to the outside. . By providing the carrier discharge section 17, the carriers contained in the treated water, that is, the carriers that did not pass through the screen 14 to the outer tank 11 and were collected by the swirling flow, can be easily removed in a concentrated state within the treated water. It can be discharged outside the device. Further, in this case, there is no need to separately provide a tank for precipitating the carrier.
Note that, as shown in FIG. 3, the carrier discharge part 17 can be formed in the bottom 111 of the separation tank 10, more specifically, in the depression 113, and has an opening in the bottom 111 of the separation tank 10 for separation. It can be a pipe extending to the outside of the tank 10.
Further, the carrier discharge portion 17 is preferably formed of a material having corrosion resistance, and can be formed of a metal such as stainless steel, for example.

As shown in FIG. 2, inside the separation tank 10, a side wall part 131 of the partition part 13 and a swirling flow forming part 132 are provided. The inner tank 12 is formed into sections so as to accommodate the tank 12 therein. The inner tank 12 thus partitioned is a space in which, for example, treated water containing carriers that has flowed in from the reaction tank via the inflow part 15 exists, and is mainly a space containing carriers. A space S1 where a swirling flow is formed by the treated water (the area marked with the symbol S1 and surrounded by a broken line in FIG. 5; hereinafter also referred to as the swirling flow forming space S1), and a space S2 where the carriers that are settling are collected (see FIG. 5). A range marked with the symbol S2 and surrounded by a broken line (hereinafter also referred to as carrier recovery space S2) may be formed. By providing the carrier recovery space, the carriers can settle without being caught up in the swirling flow velocity.
In addition, a space is formed inside the outer tank 11 in which the treated water containing the carriers in the inner tank 12 passes through a screen 14 (described later) and is collected, and the carriers present in the outer tank 11 are separated. Water flows out from the outflow portion 16 to the outside.
In this way, the partitioning section 13 partitions the inner tank 12 and the outer tank 11 so that the treated water before and after separation of the carriers does not mix with each other.

In this embodiment, the partitioning section 13 is specifically illustrated in FIGS. 2, 4, 5 (view of the separation tank 10 from the front), FIG. As shown in 7, the inner tank 12 includes a curved swirling flow forming part 132 and a side wall part 131 for generating a swirling flow of treated water containing carriers. Further, in the illustrated example, in order to appropriately guide the treated water containing carriers flowing in from the inflow portion 15 into the inner tank 12, the partition portion 13 is provided with an upper portion of the swirl flow forming portion 132 and the side wall portion 131 (in the illustrated example, It further includes a conductive plate portion 133 extending from the edge of the opening formed in the upper portion in the vertical direction.
Note that the partition portion 13 is preferably formed of a material having corrosion resistance, and can be formed of a metal such as stainless steel, for example.

In the illustrated example, the side wall portions 131 are a pair of plate-shaped portions whose surfaces extend in a direction along the inflow direction of the treated water containing carriers from the inflow portion 15, as shown in FIGS. 4, 7, etc. . More specifically, the side wall portion 131 is located apart from the side portion 112 of the separation tank 10 and defines the outer periphery (side surface) of the swirling flow forming space S1 in the inner tank 12.
The side wall portion 131 has a surface extending in a direction along the inflow direction of the treated water containing carriers flowing from the inflow portion 15. In other words, as shown in FIG. 6, when viewed from above, the inflow portion 15 is The surface of the side wall portion 131 extends in the direction along which the side wall portion 131 extends. As a result, when treated water containing carriers flows into the inner tank 12 and a swirling flow is formed, the side wall portion 131 is positioned on the side of the swirling flow (the overall shape of the swirling flow is cylindrical). In this case, the flow direction of the swirling flow is along the curved surface of the cylinder.The side of the swirling flow is the bottom side of the cylinder).
Further, the side wall portion 131 holds a screen 14, which will be described later, and the screen 14 is located at the center of the side wall portion 131, as shown in FIG. Further, the lower end of the side wall portion 131 in the vertical direction is located at the opening of the recess 113 in the bottom portion 111 of the separation tank 10 .

Note that when the surface of the side wall portion 131 “extends in the direction along the inflow direction of the treated water containing the carrier” or “extends in the direction along the direction in which the inflow portion extends”, the direction in which the surface of the side wall portion 131 extends is It does not have to be strictly the same direction as the inflow direction of the treated water containing the water. For example, a deviation of about 15 degrees or less is acceptable, and preferably 7 degrees or less. Further, in the illustrated example, the screen 14 is provided in the side wall portion 131, but in this embodiment, the entire side wall portion 131 may be formed of the screen 14.
Although the side wall portion 131 is a pair of plate-shaped portions in the illustrated example, for example, when the inner tank 12 is placed closer to one side of the side portion 112 of the separation tank 10, The side wall portion 131 may be one plate-shaped portion and the side portion 112 of the separation tank 10 (that is, the side wall portion 112 of the separation tank 10 may also be used as the side wall portion 131 of the partition portion 13. ).

In the illustrated example, the swirling flow forming portions 132 are a pair of plate-shaped portions adjacent to each of the pair of side wall portions 131, as shown in FIG. 4 and the like. More specifically, the swirling flow forming portion 132 is located apart from the side portion 112 of the separation tank 10 and defines the outer periphery (side surface) of the swirling flow forming space S1 in the inner tank 12. The swirling flow forming part 132 is provided so that its surface is perpendicular to the side wall part 131, and as shown in FIG. The surface of the forming portion 132 is extended.
In addition, as shown in FIG. (the lateral length up to) gradually increases from the top to the bottom in the vertical direction of the inner tank 12, reaches the maximum length, and then gradually decreases.
More specifically, as shown in FIG. 5, the pair of swirling flow forming portions 132 are arc-shaped curved plates, and the inner tank 12 partitioned by the pair of swirling flow forming portions 132 is It has an approximately circular or elliptical shape when viewed from the front.
The pair of swirling flow forming parts 132 have different curvature radii of circular arcs, and the one pair of swirling flow forming parts 132 is located at the front in the inflow direction of the treated water containing carriers from the inflow part 15. Although the radius of curvature of the swirling flow forming portion 132 is larger than that of the swirling flow forming portion 132 located at the rear in the inflow direction, the radius of curvature may be the same.
Further, the lower end of the swirling flow forming portion 132 in the vertical direction is located at the opening of the recess 113 in the bottom portion 111 of the separation tank 10 .

Note that the expressions such as "the surface of the swirling flow forming part 132 is perpendicular to the side wall part 131" and "extending in a direction perpendicular to the direction in which the inflow part 15 extends" do not necessarily have to be strictly orthogonal; It is acceptable that there is a deviation of about 7° or less, and preferably 7° or less.
Since the swirling flow forming portion 132 is formed of an arc-shaped curved plate (curved surface R shape), it has the effect of smoothing the flow in the inner tank and forming a good swirling flow. When the tank is configured as a rectangular parallelepiped or when a flat plate is used to form a swirling flow, the flow stagnates at the corners, reducing the swirling flow velocity and reducing the cleaning effect of the screen, leading to blockages. It becomes easier.
Furthermore, by forming the swirling flow forming part 132 into a curved surface, the carrier hits and comes into contact with the curved surface during the swirling flow, which softens the impact and reduces damage to the carrier. It has the effect of suppressing severe peeling, reduces excessive collision with the wall surface, and prevents excessive peeling of the biofilm attached to the carrier.

In the inner tank 12 of the separation tank 10, as described above, a swirling flow can be formed with the treated water containing carriers that has flowed in from the inflow portion 15. The swirling flow can be formed by the swirling flow forming part 132, and specifically, as shown in FIG. A swirling flow is formed by guiding the water to swirl.
In this embodiment, the shape of the swirling flow forming section 132 is not particularly limited as long as it can form a swirling flow with treated water containing a carrier.

In the illustrated example, the guide plate portion 133 is provided to appropriately guide the treated water containing carriers flowing from the inflow portion 15 into the inner tank 12, as shown in FIGS. 2, 4, and 7. , has a horizontal plate part 134 extending in the horizontal direction from the edge of the opening formed at the upper part of the side wall part 131 and the swirling flow forming part 132, and a vertical plate part 135 extending in the vertical direction. The horizontal plate part 134 and the vertical plate part 135 prevent the treated water containing carriers in the inner tank 12 and the outer tank 11 from mixing with the treated water from which the carriers have been separated, and prevent the treated water containing carriers flowing from the inflow part 15 from mixing. Water can be guided to the openings formed in the upper portions of the side wall portion 131 and the swirl flow forming portion 132.

Further, the partition part 13 that partitions the inner tank 12 of the separation tank 10 can have a part that partitions the space S2 in which a swirling flow is formed and collects the carriers that are settling. The depression 113 can be provided as a part that partitions the space S2. In this example, the depression 113 is arranged below the side wall section 131 and the swirling flow forming section 132 in the vertical direction (downward in the vertical direction), as shown in FIGS. As shown, within the swirling flow forming space S1 formed by the side wall portion 131 and the swirling flow forming portion 132, the particles may be unevenly distributed along the swirling flow and then settle into the depression 113.
In the present embodiment, the part of the inner tank 12 that collects the carriers is replaced by a funnel formed of, for example, a metal plate, which is connected to the lower part of the side wall part 131 and the swirling flow forming part 132 in the vertical direction. It can also be formed by providing a shaped recovery plate (not shown).

In addition, it is preferable that the part forming the space S2 as the partition part 13 is connected to the carrier discharge part 17 for discharging the carrier to the outside. Specifically, as shown in FIG. 3, in the illustrated example, the carrier discharge part 17 is formed at the bottom of the depression 113.

As shown in FIG. 2 and the like, the carrier separation device 1 includes a screen 14 that is provided on the side wall 131 of the compartment 13 to separate the carriers and to allow the treated water containing the carriers to pass from the inner tank 12 to the outer tank 11. . Specifically, the screen 14 is not particularly limited, but any material such as punched metal, wedge wire, wire mesh, etc. may be used as long as its opening is small relative to the size of the carrier to be separated. Can be done. As the screen 14, it is preferable to use a mesh size smaller than the size of the carrier. Specifically, the size of the carrier is 25 to 90%, more preferably 40 to 80%.
Further, the material of the screen 14 is preferably a corrosion-resistant material, and can be made of stainless steel, for example.

The screen 14 is provided in the partition part 13, specifically in the partition part 13, so as to be arranged on the side of the swirling flow. The screen 14 is provided at least at the center of the side wall 131 when the partition 13 has the side wall 131 as in the illustrated example.
Further, the size of the screen 14 can be arbitrarily determined depending on the operating conditions of the apparatus, the size of the carrier to be separated in the treated water containing the carrier, and the like. Further, in the illustrated example, one pair of screens 14 are provided, but only one of the screens 14 may be provided.

As shown in FIGS. 2, 3, etc., the carrier separator 1 can include a drain drainage section 19 at the bottom 111 of the separation tank 10, which allows the operation of the carrier separator 1 to be stopped and the separation tank 10 to be drained. When cleaning or inspecting the interior, treated water from which residual carriers have been separated can be drained. The drain drainage section 19 can be a pipe made of metal, such as stainless steel, that has an opening in the bottom 111 of the separation tank 10 and extends to the outside of the separation tank 10 .

Although not shown, the carrier separation device 1 can include a sensor capable of measuring the water level in the separation tank 10. Specifically, the sensor can be provided within the separation tank 10 or the inner tank 12. Although the carrier separation device 1 has a feature that the screen is not easily clogged, the screen may become clogged due to the state of biofilm on the surface of the carrier or the inflow of foreign matter. If the screen 14 were to become clogged with carriers or foreign matter, it is assumed that the water level in the inner tank 12 would rise. 12 can be prevented from overflowing. Furthermore, when the water level rises, control can be performed to unclog the screen 14, or the inflow section 15 can be closed.
In addition, in the illustrated example of the carrier separation device 1, during normal operation, the water level can be set at a height near the opening formed by the side wall 131 and the swirling flow forming section 132 of the partition section 13. .

Although not shown, the carrier separation device 1 can further include a discharge adjustment section that adjusts the discharge amount of the treated water containing the carriers in the inner tank 12. Specifically, the discharge adjustment section may be provided in the carrier discharge section 17, and in this case, the discharge amount of the treated water containing the carrier from the carrier discharge section 17 is adjusted by a pump or valve as the discharge adjustment section. be able to. Alternatively, the carrier discharge part 17 can be provided with a drain pipe branching from the carrier discharge part 17 and a valve that adjusts the opening/closing of the drain pipe as a discharge adjustment part, and by controlling the valve, the discharge from the carrier discharge part 17 can be provided. The amount of discharged water containing the carrier can be adjusted. Alternatively, although not shown, a drain pipe opening into the inner tank 12 may be provided below the inner tank 12 in the vertical direction, specifically, in a portion of the bottom 111 of the separation tank 10 located within the inner tank 12. A valve for adjusting the opening and closing of the drain pipe can be provided as the discharge adjustment section, and by controlling the valve, the discharge amount of the treated water containing the carrier in the inner tank 12 can be adjusted.

In this manner, by providing the carrier separation device 1 with the discharge adjustment section, the screen 14 can be cleaned, for example, when the screen 14 is clogged with carriers. Specifically, for example, while the carrier separation device 1 is in operation, the amount of treated water containing the carriers present in the inner tank 12 is reduced by increasing the discharge of the treated water containing the carriers by the discharge adjustment section. However, as a result, the amount of treated water containing carriers permeating from the inner tank 12 to the outer tank 11 through the screen 14 is reduced, or the treated water from which the carriers have been separated is transmitted from the outer tank 11 to the inner tank 12. Since the flow flows back, carriers clogging the screen 14 can be removed.

Here, in a carrier separation device 2 according to another embodiment of the present invention, in addition to the configuration of the carrier separation device 1 described above, the carrier separation device 2 includes a cleaning section 21 as shown in FIGS. 8 and 9. By moving along the surface of the screen 14, the cleaning section 21 can remove and clean the carriers that have clogged the screen 14.

Specifically, as shown in FIGS. 8 and 9, the cleaning unit 21 includes a brush 22 that cleans the surface of the screen 14 by sliding, and a sliding brush 22 that slides the brush 22 laterally on the surface of the screen 14. It has a mechanism and a drive source 26 that operates the sliding mechanism.
In the illustrated example, the brush 22 is provided in a posture extending in the vertical direction, and its length is longer than the length of the screen 14 in the vertical direction. Note that in the illustrated example, there are two brushes 22, but the number can be any number.
The sliding mechanism is not particularly limited as long as it can move the brush 22 along the inner surface of the inner tank of the screen 14, but the sliding mechanism includes a pair of annular belts 24 and a roller that supports the belt 24 in the inner tank. 25.
Specifically, four rollers 25 are installed near the lateral ends of a pair of screens 14 so as to extend vertically inside the inner tank, and a pair of annular belts 24 are installed around the four rollers. It is attached around 25. As shown in FIG. 9, the pair of belts 24 are attached near the lower end and near the upper end of the roller 25 so as to be located above and below the screen 14 in the vertical direction, and are attached to both ends of the brush 22. Connected.
Furthermore, the drive source 26 operates a sliding mechanism, and in the illustrated example, is provided so as to rotate the pair of belts 24.
As described above, since the cleaning section 21 includes the brush 22, the sliding mechanism, and the drive source 26, the brush 22 moves around the surface of the screen 14 to sweep it, removes carriers that have clogged the screen 14, and cleans the screen. 14 can be washed.

In the illustrated example, the cleaning unit 21 is provided inside the inner tank of the screen 14 and moves along the inner surface of the inner tank of the screen 14. It may be provided on the side (outside the inner tank) and moved along the surface of the screen 14 on the outer tank side for cleaning.

Next, the multistage carrier separation device of this embodiment will be explained.
The multi-stage carrier separation device 3 of the present embodiment is a device that can separate carriers holding microorganisms and contaminants in treated water, and the carrier separation device 1 of the embodiment of the present invention described above is A plurality of them are connected and provided.
Specifically, the multistage carrier separation device 3 of this embodiment includes a first separation device 31 and a second separation device 32, as shown in FIG. can have the same configuration as the carrier separation device 1 of the embodiment of the present invention described above, except for the opening of the screen. More specifically, the first separation device 31 and the second separation device 32 each include a separation tank 10 including an outer tank 11 and an inner tank 12, and an inflow section 15 through which treated water containing a carrier flows into the inner tank 12. , 34, and outflow portions 33, 16 for allowing the treated water from which the carrier has been separated to flow out from the outer tank 11, and the outer tank 11 accommodates an inner tank 12 therein, and the inner tank 12 includes: It is formed of a partition section 13 that includes a curved swirl flow forming section 132 and a side wall section 131 for generating a swirl flow of treated water containing carriers inside, and a screen 14 provided on the side wall section 131. 14 is disposed on the side of the swirling flow, and allows the treated water from which impurities or carriers have been separated to permeate from the inner tank 12 to the outer tank 11.
The outflow section 33 of the first separation device 31 and the inflow section 34 of the second separation device 32 are connected, and the screen 14 of the first separation device 31 has a larger opening than the screen 14 of the second separation device 32. It has become.

Since the multistage carrier separation device 3 of this embodiment has such a configuration, it is possible to prevent the screen from being clogged with the carriers and to easily separate the carriers from the treated water containing the carriers. More specifically, treated water containing a carrier may contain impurities derived from organic wastewater (raw water) before treatment, or may contain impurities mixed in from the outside during the treatment process. If treated water containing not only carriers but also impurities is to be separated using one carrier separation device, the opening of the screen must be made relatively small so that the carriers do not pass through the screen. Contaminants can easily clog the screen. If the screen becomes clogged, it becomes necessary to perform maintenance such as cleaning the screen.
On the other hand, in the multi-stage carrier separation device 3 of the present embodiment, the opening of the screen 14 of the first separation device 31 is larger than the opening of the screen 14 of the second separation device 32, so that Contaminants can be separated by the first separation device 31. Further, the carrier can be separated in the second separator 32 after passing through a screen in the first separator 31 and flowing out from the outlet of the first separator 31 as treated water containing the carrier.
That is, according to the multistage carrier separation device 3 of this embodiment, maintenance such as cleaning of the screen can be made more efficient, and contaminants and carriers can be easily separated from the treated water and taken out of the device 3.

Here, in this embodiment, the opening of the screen in the first separation device 31 is larger than the opening of the screen in the second separation device 32; Preferably, the opening is 120% or more of the size of the carrier. Further, it is preferable that the screen in the second separation device 32 has a mesh size smaller than the size of the carrier. Specifically, the size of the carrier is 25 to 90%, more preferably 40 to 80%.
In addition, when containing 40% or more of low-molecular-weight organic substances with carbon numbers of 5 or less, such as acetic acid, lactic acid, propionic acid, methanol, and ethanol, acid fermentation is not necessary, so the acid fermenter 42 may function as a pH adjustment tank. , may become unnecessary.

In this embodiment, the first separation device 31 collects and discharges impurities, and allows the carrier to permeate. In the second separation device 32, the carrier is recovered and returned, and the treated water and fine sludge from which the carrier has been separated are permeated.

Next, a method of operating the carrier separation apparatus of this embodiment will be explained.
The operating method of the carrier separation device of the present embodiment is an operating method performed using the carrier separation device 1 of the embodiment of the present invention described above, in which the swirling flow rate of the swirling flow of treated water containing the carrier is 80 m/h or more. The ratio of the permeation flow rate of the treated water containing the carrier in the screen 14 to the swirling flow velocity (permeation flow velocity/swirling flow velocity) is 1 or less.
More specifically, as shown in FIG. 7, the carrier separator 1 is operated by causing treated water containing carriers to flow into the inner tank 12 from the inflow portion 15 of the carrier separator 1, and to process the treated water by flowing the treated water into the inner tank 12. A swirling flow is formed with water, and then the carriers are separated by the screen 14, and the treated water from which the carriers have been separated flows into the outer tank 11.Then, the treated water from which the carriers have been separated in the outer tank 11 is transferred to the outflow section. This is done by draining from 16. In this case, in the operating method of the carrier separation device 1 of the present embodiment, the flow rate of the swirling flow of the treated water containing carriers is set to be 80 m/h or more, and the permeation flow rate of the treated water containing the carriers in the screen 14 is set relative to the swirling flow velocity. The ratio (permeation flow rate/swirling flow rate) is set to 1 or less.
In the operating method of the carrier separation device of the present embodiment, by operating under the above conditions, clogging of the screen 14 with carriers can be prevented, and the carriers can be easily separated from the treated water containing the carriers.

Here, in this embodiment, it is preferable that the amount of treated water flowing in from the inflow part 15 of the carrier separation device 1 is 7 m ³ /h or more. Moreover, it is preferable that the swirling flow velocity within the inner tank 12 be 80 m/h or more. By setting the above flow rate, it is possible to further prevent the carrier from clogging the screen 14 and to more easily separate the carrier from the treated water containing the carrier.
In addition, in the operating method of the carrier separation device of the present embodiment, it is not essential that the carrier separation device 1 includes the carrier discharge section 17, but it is preferable to include the carrier discharge section 17.

Further, the ratio of the permeation flow rate to the swirling flow rate is preferably 0.5 or less. By setting the ratio to 0.5 or less, clogging of the screen 14 with carriers can be further suppressed.
Moreover, it is preferable that the said ratio is 0.1 or more. By setting the ratio to 0.1 or more, it is possible to prevent the amount of separated treated water from decreasing too much.

In this specification, the flow velocity of the swirling flow is defined as the inflow flow rate Q (m ³ /h) of treated water containing carriers flowing in through the inflow portion 15, the swirling flow radius R (m), and the swirling flow width W ( It refers to the value (m/h) divided by ^the value multiplied by ).
In addition, the permeation flow rate refers to the value (m/h) obtained by dividing the inflow flow rate Q (m ³ /h) by the area A (m ² ) of the screen 14 (i.e., the permeation flow rate (m/h) = Q (m ³ /h)÷A(m ² )).
Furthermore, the above swirling flow radius R (m) refers to the space in the inner tank 12 where the swirling flow is formed (swirling flow forming space S1 ), and the radius can be calculated assuming that the area is a circle.Also, as shown in FIG. In this case, the center of the swirling flow and the inner surface of the swirling flow forming part 132 located further away from the center (the left swirling flow forming part 132 in FIG. 6) were measured in the horizontal direction. It can also be length.
Furthermore, the above-mentioned swirling flow width W (m) is the distance between the inner surfaces of partitions (for example, side wall portions 131, etc.) that partition the swirling flow from the side, and for example, as shown in FIG. When there is a pair of screens 14 provided on a pair of side wall portions 131 on the sides of the screen, the distance between the surfaces of the screens 14 can be set as shown in FIG.
Moreover, the area A (m ² ) of the screen 14 is the area of the area where the screen exists, and is the area including the skeleton parts such as wires.

The flow rate of the above-mentioned swirling flow and the permeation flow rate at the screen 14 are not particularly limited, but the inflow flow rate Q (m ³ /h) of treated water containing carriers flowing into the inflow section 15 may be adjusted, or the area of the screen 14 may be adjusted. It can be adjusted by adjusting A (specifically, changing the size of the screen 14 itself or adjusting the opening of the screen 14).

By the way, in the operating method of the carrier separation apparatus 1 of the present embodiment, clogging of the screen 14 with carriers and the like can be reduced by the above-mentioned operating conditions, but the following cleaning step can be included.
Specifically, in the cleaning step, the inflow section 15 is provided with an inflow adjustment section (not shown) that can adjust the inflow amount of the treated water containing the carrier, and the inflow adjustment section allows the flow of the treated water containing the carrier to be adjusted. Temporarily reduce or stop the inflow. The carriers clogging the screen 14 are clogged by the water pressure when the treated water containing the carriers passes through the screen 14. However, by temporarily reducing or stopping the inflow amount, the screen 14 can be clogged. The permeation flow rate and the water pressure caused by the permeation of the treated water containing the carrier are reduced accordingly, and the carrier clogging the screen 14 can be settled and the screen 14 can be washed.
Further, instead of or in addition to the adjustment by the inflow adjustment section, the carrier separation device 1 is provided with a discharge adjustment section that can adjust the discharge amount of the treated water containing the carriers in the inner tank 12. , the discharge adjustment section adjusts so that the discharge amount of the treated water containing the carrier increases. As a result, the screen 14 can be cleaned by lowering the permeation flow rate in the screen 14, similar to when the inflow adjustment section temporarily reduces or stops the inflow of treated water containing carriers. can.
The adjustment in the discharge adjustment section can be made by adjusting the pump or valve as a discharge adjustment section provided in the carrier discharge section 17, or by connecting a drain pipe and a drain branching from the carrier discharge section 17 to the carrier discharge section 17. A valve that adjusts the opening and closing of the piping is provided as a discharge adjustment part and the valve is controlled, or specifically, the inner tank 12 of the bottom 111 of the separation tank 10 is provided below the inner tank 12 in the vertical direction. This can be done by providing a drain pipe that opens into the inner tank 12 and a valve that adjusts the opening/closing of the drain pipe as a discharge adjustment part in a portion located inside the inner tank 12, and controlling the valve.

In addition, as another cleaning step, as shown in FIGS. 8 and 9, the screen 14 can also be cleaned by equipping the carrier separation device 2 with a cleaning section 21 and using the cleaning section 21.
Furthermore, as other cleaning steps, mechanical cleaning (high-pressure nozzle jet water, sprinkler, scraper, etc.) can be provided in the separation tank 10, and cleaning can be performed using the mechanical cleaning.
In this embodiment, the cleaning process can be performed periodically by setting a timer or the like, or can be performed when the water level reaches a predetermined water level or higher using a sensor that can measure the water level. .

Next, the anaerobic treatment apparatus of this embodiment will be explained.
The anaerobic treatment device 4 of this embodiment is a device for treating organic wastewater, as shown in FIG. This is a device that performs anaerobic treatment of organic wastewater containing organic matter, such as general sewage, by bringing it into contact with anaerobic microorganisms.
More specifically, the anaerobic treatment device 4 of the present embodiment includes a reaction tank 41 that performs anaerobic treatment with a carrier that holds microorganisms to obtain treated water containing the carrier, and a reaction tank 41 into which the treated water containing the carrier flows and the treated water. and a carrier separation device 1 for discharging the treated water from which the carriers have been separated. Further, the anaerobic treatment device 4 can optionally include an acid fermentation tank 42 that decomposes organic matter contained in the water to be treated to obtain acid fermentation treated water.
Further, in the anaerobic treatment apparatus 4 of this embodiment, the carrier separation apparatus 1 is the carrier separation apparatus 1 of the embodiment of the present invention described above, and the carrier separation apparatus 1 is the carrier separation apparatus 1 of the embodiment of the present invention described above. An apparatus including a carrier discharge part 17 that allows the carrier to flow out can be used. Furthermore, in the anaerobic treatment apparatus 4 of this embodiment, the carrier discharge part 17 and the reaction tank 41 are connected by a connection part (connection line (lines L5 and L4 in the illustrated example)).

In this embodiment, specifically, the acid fermentation tank 42 is a tank that decomposes organic matter contained in water to be treated such as waste liquid to obtain acid fermentation treated water. This tank can decompose organic matter (polymer) contained in wastewater into low-molecular organic acids such as acetic acid and propionic acid.
The acid fermentation treated water obtained in the acid fermentation tank 42 flows out into the reaction tank 41 through a line L4 connecting the acid fermentation tank 42 and the reaction tank 41.

In the reaction tank 41, water to be treated (waste liquid or acid fermentation treated water when the above-mentioned acid fermentation tank 42 is provided) is introduced, and the water to be treated is anaerobically treated with a carrier that holds microorganisms. get water. Although not particularly limited, the reaction tank 41 contains granule sludge and carriers, and allows organic wastewater to flow upward to perform high-load, high-speed processing. In the anaerobic reaction tank 41 (methane fermentation tank), biogas (methane gas) generated by the anaerobic reaction rises within the anaerobic reaction tank 41, is discharged to the outside from the upper part of the anaerobic reaction tank 41, and is recovered. Ru. At this time, the carrier holding the microorganisms also rises together and may flow out of the anaerobic reaction tank 41 as an overflow.
In addition, in the reaction tank 41, as shown in FIG. 1, a circulation line L1 connecting the upper and lower parts of the reaction tank 41 can be provided for circulation.
The reaction tank 41 is a complete mixing tank using mechanical or gas stirring, an upflow anaerobic sludge bed (UASB), and an expanded granular sludge bed (EGSB) as an improved version of the UASB method for high loads. ) or a reaction tank equipped with an internal gas collector, guide wall, and baffle that has an efficient flow state.

The carrier separation device 1 is the carrier separation device 1 of the embodiment of the present invention described above, in which treated water containing carriers after wastewater is treated in the reaction tank 41 or during treatment passes through the line L2, It flows into the separation tank via the inflow part of the carrier separation device 1. Then, in the carrier separation device 1, the carriers in the treated water are separated, the treated water from which the carriers have been separated flows out from the outlet, and the separated carriers (treated water with concentrated carriers) are discharged as carriers. It is discharged from the department.
The treated water discharged from the outlet of the carrier separation device 1 from which the carriers have been separated can be carried out to the outside of the anaerobic treatment device 4 through the line L3. Further, a part of the treated water from which the carriers have been separated passing through the line L3 can also be returned to the acid fermentation tank 42 again through the line L6.

In the anaerobic treatment apparatus 4 of this embodiment, the carrier discharge part of the carrier separation apparatus 1 and the reaction tank 41 are connected by a connecting part (connecting line). Specifically, in the example of FIG. 1, the line L5 extending from the carrier discharge part of the carrier separation apparatus 1 joins the line L4, and thereby the carrier discharge part of the carrier separation apparatus 1 and the reaction tank 41 are connected. ing.
In the anaerobic treatment device 4 of this embodiment, the anaerobic treatment device 4 includes the carrier separation device 1, and the carrier discharge part of the carrier separation device 1 and the reaction tank 41 are connected by a connection line. Wastewater treatment can be carried out efficiently. Specifically, when organic wastewater is anaerobically treated using a carrier, the carrier may flow out of the reaction tank 41 along with the treated water, but since the anaerobic treatment device 4 is equipped with the carrier separation device 1, , the carrier can be easily separated and discharged.
Then, the discharged carrier can be quickly returned to the reaction tank 41 and used again for wastewater treatment. Moreover, since the carrier separation device 1 can easily obtain treated water from which carriers have been separated, it is also possible to easily obtain treated water from which anaerobically treated carriers have been separated.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

(Consideration 1)
In study 1, treated water containing carriers was allowed to flow into a carrier separation device as shown in FIG. 2 under predetermined conditions for 3 hours, and it was verified whether treated water from which carriers had been separated could be obtained. The results are shown in Table 1.
Note that the treated water is wastewater obtained by subjecting organic wastewater to anaerobic treatment using a polyvinyl alcohol gel carrier in a reaction tank. Further, the screen of the carrier separation device has a size of 0.25 m ² and an opening of 2 mm. The inflow amount of treated water containing carriers, the flow rate of the swirling flow, and the permeation flow rate are shown in the table below.
Furthermore, whether or not the screen was clogged was determined by visually checking the rise in the water level inside the interior.

As can be seen from Table 1, in Experimental Examples 2 and 3, in which the swirling flow velocity in the inner tank was set to 80 m/h or higher, the screen was clogged less than in Experimental Example 1, in which the swirling flow velocity was set to 80 m/h or lower. It was possible to easily and efficiently obtain treated water from which the carrier had been separated.

(Consideration 2)
In study 2, organic wastewater was anaerobically treated in a reaction tank in the same manner as study 1, and various separation methods were used to obtain treated water from which carriers had been separated. At that time, we will consider the maintainability, introduction cost, and corrosion resistance of the equipment and equipment used in conjunction with each separation method adopted for separation, as well as whether or not the screen used during separation is clogged. , each separation method was evaluated. The results are shown in Table 2 below.
Note that Study 2 was conducted for 3 hours in the same manner as Study 1. The treated water in the reaction tank is wastewater obtained after anaerobic treatment of organic wastewater using a polyvinyl alcohol gel carrier. Further, when a screen is used, the screen used has a size of 0.25 m ² and an opening of 2 mm.

In Example 1, a carrier separation apparatus as shown in FIG. 2 was used to separate the carriers, and the apparatus was operated under the same conditions as Experimental Example 3 in Study 1.
In Comparative Example 1, as shown in FIG. 11(a), the carrier was separated using a separation tank 52a different from the reaction tank 51a. Specifically, the treated water containing the carrier flowing out from the reaction tank 51a is caused to flow into the separation tank 52a, and then the carrier is separated in the separation tank 52a without generating a swirling flow in the treated water containing the carrier. This was done by transmitting the light through a screen 53a that is arranged obliquely in front of the outflow section. Note that the flow rate from the reaction tank 51a was 12 m ³ /h.
In Comparative Example 2, as shown in FIG. 11(b), a screen 53b is provided to cover the opening of the outflow part in the reaction tank 51b, and the treated water containing the carrier is allowed to pass through the screen 53b, thereby removing the carrier. Separation was performed. Note that the flow rate from the reaction tank 51b was 12 m ³ /h.
In Comparative Example 3, as shown in FIG. 11(c), the carrier was separated using a separation tank 52c different from the reaction tank 51c. Specifically, before the treated water containing the carrier flowing out from the reaction tank 51c flows into the separation tank 52c, bubbles such as methane gas adhering to the carrier are separated using a gas-liquid separation tube, and the carrier is separated from the separation tank 52c. This made it easier to settle inside. Then, the treated water in which the carriers had settled and been separated was passed through a screen 53c disposed in front of the outflow portion, thereby obtaining treated water in which the carriers had been separated. Note that the flow rate from the reaction tank 51c was 12 m ³ /h.
In Comparative Example 4, as shown in FIG. 11(d), a separation tank 52d separate from the reaction tank 51d was used. Specifically, the separation tank 52d is provided with a settling section in which the carrier settles at the bottom of the tank. The treated water containing the carrier flowing out from the reaction tank 51d is made to flow into the separation tank 52d, and the carrier is separated in the separation tank 52d while the carrier is sedimented in the sedimentation section in the separation tank 52d. The carrier was separated by passing through the screen 53d disposed in front of the outflow portion without generating a swirling flow. Note that the flow rate from the reaction tank 51d was 12 m ³ /h.
In Comparative Example 5, as shown in FIG. 11(e), a screen 53e was provided near the water surface in the reaction tank 51e, and the water was discharged using a pump. The screen 53e was surrounded by a rectifying plate that made it difficult for carriers to be included in the treated water flowing around the screen 53e. Note that the flow rate from the reaction tank 51e was 12 m ³ /h.
In Comparative Example 6, as shown in FIG. 11(f), the wastewater in the reaction tank 51f was treated in an upward flow using an acid gas device, and the treated water containing the carrier produced by treating the wastewater was When flowing out of the reaction tank 51f, the carriers were separated by passing through a screen 53f that was tilted in front of the outlet. Note that the flow rate from the reaction tank 51f was 12 m ³ /h.
In Comparative Example 7, as shown in FIG. 11(g), the carrier was separated using an open separation tank 52g different from the reaction tank 51g. Specifically, a screen 53g was arranged in an inclined state at the opening of the separation tank 52g, and the treated water containing the carrier flowing out from the reaction tank 51g was flowed toward the screen 53g from above the screen 53g. Thereby, the carrier is filtered without passing through the screen and returned from the separation tank 52g to the reaction tank 51g. The treated water from which the carrier had been separated passed through 53 g of screens and flowed out from the outlet of the separation tank 52 g. Note that the flow rate from the reaction tank 51 g was 12 m ³ /h.

In addition, evaluations of maintainability, cost, corrosion resistance, and presence or absence of clogging were performed using the following methods.
Maintainability was compared based on the difficulty of inspecting the screen section.
Cost efficiency was compared based on construction costs.
Corrosion resistance was compared based on whether or not outside air (oxygen) was allowed to flow into the separator.
The presence or absence of clogging was compared by the frequency of clogging on the screen surface.

As shown in Table 2, by using the carrier separation device according to the present invention, good results were obtained in terms of maintainability, cost efficiency, corrosion resistance, and the presence or absence of clogging.

According to the present invention, by generating a swirling flow in treated water containing a carrier, it is possible to prevent the carrier from clogging the screen and to separate the carrier easily from the treated water containing the carrier. It is possible to provide a device, a method for operating a carrier separation device, a multistage carrier separation device, and an anaerobic treatment device capable of efficiently treating wastewater.

1, 2: Carrier separation device 10: Separation tank 11: Outer tank 111: Bottom part 112: Side part 113: Recess 12: Inner tank 13: Division part 131: Side wall part 132: Swirling flow forming part 133: Guide plate part 134: Horizontal plate portion 135: Vertical plate portion 14: Screens 15, 34: Inflow portions 16, 33: Outflow portion 17: Carrier discharge portion 19: Drain drainage portion 21: Cleaning portion 22: Brush 24: Belt 25: Roller 26: Drive portion 3: Multistage carrier separation device 31: First separation device 32: Second separation device 4: Anaerobic treatment device 41: Reaction tank 42: Acid fermentation tanks 51a, 51b, 51c, 51d, 51e, 51f, 51g: Reaction tank 52a , 52c, 52d, 52g: separation tanks 53a, 53b, 53c, 53d, 53e, 53f, 53g: screen L1: circulation lines L2 to L6: line S1: swirling flow forming space S2: carrier recovery space R: swirling flow radius W :Swirling flow width

Claims (5)

It is formed of an outer tank, and a compartment including a curved swirling flow forming part and a side wall part for generating a swirling flow of the treated water containing carriers holding microorganisms housed inside the outer tank. an inner tank, and a separation tank comprising;
a screen that is disposed on the side wall on the side of the swirling flow and allows the treated water from which the carrier has been separated to pass from the inner tank to the outer tank;
an inflow section through which the treated water containing the carrier flows into the inner tank;
an outflow portion that allows the treated water from which the carrier has been separated to flow out from the outer tank;
a carrier discharge part provided at the bottom of the inner tank for discharging the carrier separated by the screen from the inner tank to the outside;
has
an inflow adjustment section that is provided in the inflow section and that enables adjustment of the inflow amount of the treated water containing the carrier, and that temporarily reduces or stops the inflow amount;
a discharge adjustment unit that enables adjustment of the discharge amount of the treated water containing the carrier in the inner tank and increases the discharge amount of the treated water containing the carrier;
A carrier separation device characterized by having at least one of the following. a brush that cleans the surface of the screen by sliding;
a sliding mechanism that slides the brush laterally on the surface of the screen;
a drive source that operates the sliding mechanism;
The carrier separation device according to claim 1, characterized in that it has: The carrier separation device according to claim 1 or 2, wherein the swirling flow velocity of the swirling flow is 80 m/h or more, and the ratio of the permeation flow velocity of the treated water in the screen to the swirling flow velocity is 1 or less. How to drive. A multi-stage carrier separation device capable of separating carriers holding microorganisms and impurities in treated water containing the carriers and impurities,
The multistage carrier separation device includes a first separation device and a second separation device,
The first separation device and the second separation device each include a separation tank including an outer tank and an inner tank, an inflow portion through which treated water containing the carrier flows into the inner tank, and a processing unit from which the carrier is separated. an outflow portion that allows water to flow out from the outer tank;
Equipped with
The outer tank accommodates the inner tank therein,
The inner tank is formed of a division part including a curved swirling flow forming part and a side wall part for generating a swirling flow of the treated water containing the carrier, and a screen provided on the side wall part. is,
The screen is provided in the first separation device and the second separation device, is placed on the side of the swirling flow, and is configured to transmit the treated water from which impurities or carriers have been separated from the inner tank to the outer tank. and the opening of the screen of the first separation device is larger than the opening of the screen of the second separation device,
the outflow portion of the first separation device and the inflow portion of the second separation device are connected;
The first separation device or the second separation device has a carrier discharge part provided at the bottom of the inner tank for discharging the carriers separated by the screen from the inner tank to the outside,
an inflow adjustment section that is provided at the inflow section of the first separation device or the second separation device, and that makes it possible to adjust the inflow amount of the treated water containing the carrier, and temporarily reduces or stops the inflow amount;
a discharge adjustment unit that enables adjustment of the discharge amount of the treated water containing the carrier in the inner tank and increases the discharge amount of the treated water containing the carrier;
A multistage carrier separation device characterized by comprising at least one of the following. an acid fermenter that decomposes organic matter contained in the water to be treated to obtain acid-fermented water;
a reaction tank into which the acid fermentation treated water flows, anaerobically treating the acid fermentation treated water with a carrier in which microorganisms are retained , and obtaining treated water containing the carrier;
an inner tank formed of an outer tank and a division part containing a curved swirling flow forming part and a side wall part for generating a swirling flow of the treated water containing the carrier inside the outer tank; and a separation tank comprising;
a screen that is disposed on the side wall on the side of the swirling flow and allows the treated water from which the carrier has been separated to pass from the inner tank to the outer tank;
an inflow section through which the treated water containing the carrier flows into the inner tank;
an outflow portion that allows the treated water from which the carrier has been separated to flow out from the outer tank;
a connecting part that connects the reaction tank and a carrier discharge part that is provided at the bottom of the inner tank and discharges the carrier to the outside;
has
an inflow adjustment section that is provided in the inflow section and that enables adjustment of the inflow amount of the treated water containing the carrier, and that temporarily reduces or stops the inflow amount;
a discharge adjustment unit that enables adjustment of the discharge amount of the treated water containing the carrier in the inner tank and increases the discharge amount of the treated water containing the carrier;
An anaerobic treatment device comprising at least one of the following.