JP7426053B1 - Biological filtration device, water filtration system and water filtration method - Google Patents

Abstract

The present invention provides a biological filtration device, a water filtration system, and a water filtration method that can maintain water quality. [Solution] A biological filtration device 100 includes a filter medium storage container 10, a filter medium 20 accommodated in the filter medium storage container 10, a water supply pipe 30 that supplies water to be treated Wi to the filter medium storage container 10, and a filter A drain pipe 40 is provided to drain the treated water We from the material storage container 10. The filter medium 20 is an aggregate of a plurality of granular bodies stacked on top of each other. The water supply port 30a of the water supply pipe 30 is located above the top end 20t of the assembly. The drain pipe 40 is located below the top end 20t. The biological filtration device 100 can maintain the water level L in the filter medium storage container 10 below the top end 20t. [Selection diagram] Figure 2

Description

The present invention relates to a biological filtration device, a water filtration system, and a water filtration method.

Conventionally, various types of filtration devices have been used to maintain the quality of water in which living organisms such as fish and shellfish are cultivated or cultivated on land. As time passes, microorganisms that decompose ammonia and nitrites colonize the pores formed inside the particles that make up the filter media used in filtration devices, and the biological filtration function is impaired. is rising. On the other hand, the voids in the filter medium become clogged with dirt containing organic matter such as biological excrement and uneaten food, resulting in a decline in the physical filtration function. Washing to remove dirt from the filter media restores the physical filtration function, but washing also removes the biota that had settled in the voids, so it is necessary to restore the biological filtration effect and maintain water quality after washing. , which took time.

Patent No. 3769680

Therefore, the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a biological filtration device, a water filtration system, and a water filtration method that can maintain water quality.

In order to achieve the above purpose, the following structure is understood.
(1) The biological filtration device of the present invention includes a filter medium storage container, a filter medium accommodated in the filter medium storage container, a water supply pipe that supplies water to be treated to the filter medium storage container, and a filter medium storage container. a drain pipe for draining treated water from the container, the filter medium is an aggregate formed by stacking a plurality of granular bodies, and the water supply port of the water supply pipe is located above the top of the aggregate, The drain pipe is located below the top end, and is capable of maintaining the water level in the filter medium storage container below the top end.
(2) In (1) above, the drain pipe may be located above the lower end of the aggregate.
(3) In (1) or (2) above, the water supply port opens upward.
(4) In (1) or (2) above, the drain pipe has a low water level drain pipe and a middle water level drain pipe, and directs the flow of wastewater to the low water level drain pipe or the middle water level drain pipe. A switchable on-off valve may be provided.
(5) In (4) above, the drain pipe has a high water level drain pipe located above the top of the aggregate, and an on-off valve that can switch the flow of wastewater to the high water level drain pipe. and a blower that generates a jet of air in the filter medium storage container.
(6) The water filtration system equipped with the biological filtration device according to (1) above includes an aquarium and a ring waterway through which water in the aquarium circulates, and the ring waterway includes a first waterway returning to the aquarium and a biological filtration system. It may be branched into a second water channel leading to the filtration device.
(7) The water filtration method using the biological filtration device in (1) above includes a taking-out step of taking out a part of the aggregate from the filter medium storage container, and the remaining part of the aggregate remaining in the filter medium storage container. and a return step of returning a part of the aggregate to the filter medium storage container and stacking it above the remaining part.
(8) In the above (7), a dipping step of filling water to a water level above the top of the remaining portion may be included between the taking out step and the washing step.
(9) In the water filtration method using the biological filtration device in (5) above, the blower is started with the low water level drain pipe and the middle water level drain pipe closed and the high water level drain pipe open. , the filter medium may be stirred.

According to the present invention, it is possible to provide a biological filtration device, a water filtration system, and a water filtration method that can maintain water quality.

1 is an overall diagram of a water filtration system. FIG. 1 is a schematic diagram of a biological filtration device according to a first embodiment. It is a schematic diagram of a biological filtration device during normal operation at a medium water level. It is a schematic diagram of a biological filtration device during normal operation at a low water level. It is a schematic diagram of a biological filtration device at the time of washing. FIG. 2 is a schematic diagram of the biological filtration device immediately after cleaning. It is a schematic diagram of the water supply port of the biological filtration device concerning a 2nd embodiment. 8 is a sectional view taken along arrow A in FIG. 7. FIG.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is an overall diagram of the water filtration system S. FIG. 2 is a schematic diagram of the biological filtration device 100 according to the first embodiment. FIG. 3 is a schematic diagram of the biological filtration device 100 during normal operation at a medium water level. FIG. 4 is a schematic diagram of the biological filtration device 100 during normal operation at a low water level. FIG. 5 is a schematic diagram of the biological filtration device 100 during cleaning. FIG. 6 is a schematic diagram of the biological filtration device 100 immediately after cleaning.
In addition, below, the example which applies the biological filtration apparatus 100 to the ring waterway C of the water filtration system S which cultivates aquatic organisms, such as fish and shellfish, is demonstrated. The biological filtration device 100 is applicable not only to livestock farming where aquatic organisms such as fish and shellfish are temporarily raised in cages before being shipped, but also to water filtration systems S for aquaculture, etc. where living organisms are artificially grown and increased. You may. Note that the normal operation is a state in which aquatic organisms are raised by the water filtration system S, and is a concept that is distinguished from the time of cleaning the biological filtration device 100.

(water filtration system)
As shown in FIG. 1, the water filtration system S includes an aquarium 200 and a ring waterway C through which water from the aquarium 200 circulates. The water filtration system S circulates running water in a direction indicated by an arrow within a circular waterway C that goes around from one water tank 200 to another. In addition, in the middle of the ring waterway C (for example, the water tank 200), new water may be injected to compensate for the evaporated running water, or a part of the running water may be drained, as appropriate.

The water filtration system S mainly supplies an aquarium 200 for raising aquatic organisms such as fish and shellfish, a biological filtration device 100 that performs ammonia nitrification from wastewater from the aquarium 200, and power for circulating water in the ring waterway C. A first pump P is provided.
The first pump P may be provided immediately after the water tank 200 in the ring waterway C, or may be provided immediately after the biological filtration device 100.

The water filtration system S may include a physical filtration device 300 that removes coarse solids and suspended matter (also referred to as SS) from the waste water (filtered water, breeding water) from the aquarium 200 as appropriate. It is preferable that the physical filtration device 300 is provided upstream of the biological filtration device 100.

The water filtration system S may include a sterilizer 400 that sterilizes the waste water from the physical filtration device 300 as appropriate. The sterilizer 400 may be, for example, a UV sterilizer that sterilizes with ultraviolet light. It is preferable that the sterilization device 400 is provided upstream of the biological filtration device 100. Note that the sterilization device 400 may be provided downstream from the biological filtration device 100.

Here, the ring waterway C may branch into a first waterway C1 returning to the aquarium 200 and a second waterway C2 heading toward the biological filtration device 100. As a result, a part of the water to be treated from the water tank 200 flowing through the ring canal C can be returned to the water tank 200 and the remaining part can be directed to the biological filtration device 100, so that the flow rate and flow rate of the water flowing through the ring canal C can be reduced. It is possible to maintain a high level and reduce the load on the first pump P.

(biological filtration device)
The biological filtration device 100 according to the first embodiment includes a filter medium storage container 10, a filter medium 20 accommodated in the filter medium storage container 10, and a water supply pipe 30 that supplies water to be treated Wi to the filter medium storage container 10. , and a drain pipe 40 for draining the treated water We from the filter medium storage container 10.

The filter medium storage container 10 has a rigidity capable of withstanding water pressure caused by running water, and may be made of acrylic or vinyl chloride. , preferably transparent.

The upper part of the filter medium storage container 10 is open to the atmosphere in order to naturally supply air to the microorganisms fixed on the filter medium 20. In other words, the upper part of the filter medium storage container 10 is not sealed with a lid. Thereby, maturation of microorganisms can be promoted, and colonization of the filter medium 20 by microorganisms can be promoted.

The filter medium storage container 10 has a blower 11 for passing a jet of air (aeration) from the bottom to the top during cleaning. The blower 11 generates a jet of air within the filter medium storage container 10. A nozzle 12 connected to the blower 11 is provided in a lower portion inside the filter medium container 10 so as to face upward. Thereby, a jet of air (aeration) directed upward from below can be generated in a state where the filter medium storage container 10 is filled with running water. Therefore, the assembly of filter media 20 stacked inside the filter media storage container 10 can be washed (backwashed) inside the filter media storage container 10 without taking it out from the filter media storage container 10. Therefore, the sludge generated by biological filtration and clogging the minute gaps in the filter medium 20 can be removed from the filter medium 20, regaining space for living organisms and restoring the biological filtration function of the filter medium 20. can be done. Further, by stirring the filter medium 20 using the air jet generated by the blower 11 during normal operation, it can be used as a fluidized bed, and the formation of biofilm on the filter medium 20 can be promoted. In this way, the blower 11 can be used for both backwashing and fluidized bed use.

The lower part of the filter medium storage container 10 has a perforated plate 13 for allowing the filter medium 20 to be placed therein and for passing a jet of air from below to above during cleaning. The perforated plate 13 is provided with a plurality of holes having a size that allows the air from the nozzle 12 to pass through without letting the filter medium 20 pass through. Thereby, when backwashing, the aggregate of the filter media 20 stacked inside the filter media storage container 10 can be evenly stirred, and the filter media 20 can be effectively cleaned.

A drain 14 is provided at the bottom of the filter medium container 10 to drain water to be treated that has accumulated in the filter medium container 10 . Thereby, for example, the water used for cleaning the filter medium storage container 10 or the water used for washing the filter medium 20 can be drained from the filter medium storage container 10.

The filter medium 20 is an aggregate formed by stacking a plurality of granules. It is preferable that the granular bodies constituting the filter medium 20 are porous elastic bodies. The filter medium 20 is formed of, for example, polyvinyl alcohol (hereinafter sometimes referred to as "PVA"), and has the ability to adsorb various bacteria that grow in water, SS (Suspended Solids, dust in water), etc. It has a high water filtration function. Note that the filter medium 1 is mainly composed of polyvinyl alcohol, and may contain impurities within a range that does not inhibit physical filtration and biological filtration by microorganisms such as nitrifying bacteria. The filter medium 20 is, for example, a cube or sheet-like body having a bulk volume of 3 cm ³ to 8 cm ³ , and has a completely open cell structure with an average cell diameter of approximately 450 μm to 1500 μm, and has a bulk volume of 3000 m ² . The particles are made of PVA resin and have a specific surface area of /m ³ to 4000 m ² /m ³ and a porosity of 80% to 96%. Note that the aggregate of the filter media 20 may be a collection of a plurality of groups in which a plurality of grain states are put together in a net for ease of handling.

Here, the water supply port 30a is located above the top end 20t of the assembly of filter media 20. The drain pipe 40 is located below the top end 20t of the filter media 20 assembly. Since the water head at the water level L in the filter medium storage container 10 is the same as the water head at the height position where the drain pipe 40 is provided (for example, the height position where the middle water level drain pipe 40M is provided), the biological filtration device 100 can maintain the water level L in the filter medium storage container 10 below the top end 20t. As a result, the upper part of the assembly of filter media 20 above the water level L in the filter media storage container 10 is exposed to the air and can receive the water to be treated Wi sprinkled from the water supply port 30a. can. Therefore, by supplying the filter medium 20 with plenty of air and the water to be treated Wi, the microorganisms fixed on the filter medium 20 can be activated. Therefore, according to the biological filtration device 100, the physical filtration function can be recovered by cleaning the filter medium 20, and the biological filtration function can be recovered quickly, so that the water quality of the water flowing in the ring waterway C including the aquarium 200 can be maintained. In addition, the water supply port 30a may be single or may be plural.

The water supply port 30a opens upward. Thereby, the water to be treated Wi can be uniformly and evenly sprinkled on the upper surface of the top end 20t of the aggregate of the filter media 20 exposed to the air. Therefore, the water to be treated Wi and air can be evenly supplied to the entire filter medium 20, and the biological filtration device 100 can efficiently perform the biological filtration function.

It is preferable that (the height position of) the drain pipe 40 is located below the top end 20t of the assembly of filter media 20 and above the lower end 20b of the assembly of filter media 20. Thereby, the lower part of the assembly of filter media 20 below the water level L can be immersed in water. Therefore, when the filter medium 20 with less microbial colonization (immediately after washing) is placed in the lower part of the aggregate, and the filter medium 20 with more microbial colonization (unwashed) is placed in the upper part of the aggregate, Due to the flow of the water to be treated Wi in the direction of gravity, some of the microorganisms fixed on the filter medium 20 located at the upper part can be transferred to the filter medium 20 located at the lower part. Therefore, it is possible to promote the colonization of microorganisms on the filter medium 20 (immediately after cleaning) where there is little colonization of microorganisms. Therefore, according to the biological filtration device 100, the physical filtration function can be restored by cleaning the filter medium 20, and the biological filtration function can be restored quickly, so that the water quality of the water flowing in the ring waterway C including the aquarium 200 can be maintained.

The drain pipe 40 may include a low water level drain pipe 40L and a middle water level drain pipe 40M. The drain pipe 40 may include an on-off valve 41 that can switch the flow of waste water to the low water level drain pipe 40L or the middle water level drain pipe 40M. The drain pipe 40 may include a high water level drain pipe 40H as appropriate. The drain pipe 40 may include an on-off valve 41 that can appropriately switch the flow of waste water to the high water level drain pipe 40H.

If priority is given to decomposing ammonia nitrogen, it is preferable to open the low water level drain pipe 40L and perform normal operation at a low water level in order to increase the activity of aerobic organisms that decompose ammonia nitrogen. If you want to promote denitrification of nitrate nitrogen, close the low water level drain pipe 40L and perform normal operation at medium or high water level in order to increase the activity of anaerobic organisms that denitrify nitrate nitrogen. is preferred.
Then, the water quality (ammonia nitrogen concentration, nitrate nitrogen concentration, etc.) in the water tank 200 or the ring waterway C including the biological filtration device 100 may be checked, and the water level L may be controlled according to the water quality. This allows biological filtration to function effectively and improve water quality.

The low water level drain pipe L is provided below the height position where the medium water level drain pipe 40M is provided, preferably below the position of the perforated plate 13, that is, below the lower end 20b of the aggregate of the filter media 20.

The middle water level drain pipe 40M is provided at an intermediate height between the top end 20t and the bottom end 20b. The middle water level drain pipe 40M is preferably provided at a height that bisects the top end 20t and the bottom end 20b.

The high water level drain pipe 40H is provided at a height equivalent to or above the crown 20t, or at a height equivalent to the upper end of the filter medium storage container 10.

The on-off valves 41 may be provided individually, or may be a three-way valve or a switching valve. As a result, for example, during normal operation of the water filtration system S, as shown in FIG. By operating the on-off valve 41, the water level L can be maintained between the top end 20t and the bottom end 20b of the assembly. For example, when the filter medium 20 is completely exposed to air during normal operation of the water filtration system S, the low water level drain pipe 40L may be opened and the middle water level drain pipe 40M and the high water level drain pipe 40H may be closed. By operating the on-off valve 41 at the same time, the water level L can be maintained below the lower end 20b of the assembly. For example, when cleaning the water filtration system S (biological filtration device 100), the on-off valve 41 is operated to close the low water level drain pipe 40L and the middle water level drain pipe 40M and open the high water level drain pipe 40H. By doing so, the water level L can be maintained at a level equal to or higher than the top 20t of the aggregate.

In this way, the drain pipe 40 includes the low water level drain pipe 40L and the middle water level drain pipe 40M, so that it can be adjusted depending on the scene in which the water filtration system S is operated (normal operation, cleaning, etc.), the temperature or The water level L can be adjusted according to the environment such as water temperature.

Moreover, if the drain pipe 40 has a low water level drain pipe 40L, a middle water level drain pipe 40M, and a high water level drain pipe 40H, the height of the high water level drain pipe 40H is 20 tons at the top of the aggregate. Since it is located higher up, the water level L can be maintained above the top end 20t of the aggregate by operating the on-off valve 41 to close the low water level drain pipe 40L and the middle water level drain pipe 40M. In other words, by operating the on-off valve 41 to close the low water level drain pipe 40L and the medium water level drain pipe 40M, the water level L can be maintained high and the entire assembly can be immersed in water. With the water level L in such a high state, normal operation is performed (while maintaining the flow of the water Wi to be treated from the water supply pipe 30 to the drain pipe 40 by the first pump P), and the blower 11 is driven to accommodate the filter media. When a jet of air (aeration) is generated in the container 10, the filter medium 20 can be suspended in the water in the filter medium storage container 10 (fluidized bed). This can promote the formation of a biofilm on the filter medium 20, and since it is constantly stirred by aeration, the efficiency of contact with the water to be treated Wi can be increased. Therefore, the biological filtration function of the biological filtration device 100 can be promoted.
In addition, the drain pipe 40 includes a low water level drain pipe 40L, a middle water level drain pipe 40M, and a high water level drain pipe 40H. By operating the on-off valve 41 to close the pipe 40H and stopping the flow of the water Wi to be treated from the water supply pipe 30 to the drain pipe 40 (stopping the first pump P), the water level L is raised to a high state. It can be backwashed.

As shown in FIGS. 1 and 2, the biological filtration device 100 includes a second pump P2 that takes out the water in the filter medium storage container 10 from below the filter medium storage container 10, merges it with the water supply pipe 30, and circulates the water. It is preferable to have one. As a result, the amount of water passing through the filter medium 20 increases, so that the biological filtration function can be promoted and the load on the first pump P can be reduced.

As shown in FIG. 2, the biological filtration device 100 is removably attached to the upper end of the filter medium storage container 10 to increase the height of the filter medium storage container 10 and become part of the side wall of the container. It may have a raised portion 16. As a result, the limit amount (limit height) of filter media 20 that can be accommodated in the filter media storage container 10 can be increased, new filter media 20 can be stacked on top of the existing filter media 20, and biological filtration Performance can be improved.

(filtration method)
Next, a method for filtering water to be treated by the water filtration system S using the biological filtration device 100 will be described.

(A1) First, as shown in FIG. 1, the water tank 200 and the biological filtration device 100 are installed in the ring waterway C of the water filtration system S. Note that the biological filtration device 100 may be additionally installed in the ring waterway C of the water filtration system S in which the water tank 200 is installed in advance. Note that a physical filtration device 300 and/or a sterilization device 400 are installed in the ring waterway C of the water filtration system S as appropriate. At this time, as shown in FIG. 3, in the biological filtration device 100, the aggregate of the filter media 20 is stacked and placed on the perforated plate 13. The assembly of filter media 20 is stacked in a range from a lower end 20b that is the same as the height of the upper surface of the perforated plate 13 to a top end 20t that is approximately the same as the height of the high water level drain pipe 40H. The operation of the blower 11 is stopped.

(A11)
Here, in the biological filtration apparatus 100 during normal operation at a medium water level, as shown in FIG. 3, the low water level drain pipe 40H is closed and the medium water level drain pipe 40M is opened. Opening and closing of the high water level drain pipe 40L is optional. Here, the high water level drain pipe 40L is left open.

(A12)
Here, in the biological filtration device 100 during normal operation at a low water level, the low water level drain pipe 40L is left open as shown in FIG. The middle water level drain pipe 40M and the high water level drain pipe 40H can be opened or closed as desired. Here, the middle water level drain pipe 40M and the high water level drain pipe 40H are left open.

(A13)
Here, in the biological filtration device 100 during normal operation at a high water level, the low water level drain pipe 40L and the middle water level drain pipe 40M are closed, and the high water level drain pipe 40H is opened. Then, during normal operation, the blower 11 is driven to keep the filter medium 20 in a fluid state by constantly stirring and aerating the filter medium 20 with aeration. In this way, the biological filtration device 100 can also be used as a fluidized bed.

(A21) Subsequently, the first pump P is started, and the water to be treated Wi from the water tank 200 is circulated through the ring water channel C. Then, in the biological filtration device 100 during normal operation at a medium water level, as shown in FIG. Wi discharges. When the water supply port 30a faces upward, it is preferable because the treated water Wi discharged from the water supply port 30a falls evenly and evenly on the top end 20t of the assembly of filter media 20 like a shower. When the water to be treated Wi comes into contact with the filter medium 20, impurities are filtered out through physical action, and ammonia nitrogen, which is highly toxic to fish, is decomposed through biological action and becomes attenuated. The water flows in the direction of gravity from the upper part of the body to the lower part, and is drained into the drain pipe 40. Then, the water level L is stabilized at the same level as the middle water level drain pipe 40M. Then, the lower part of the assembly of filter media 20 is immersed in the water to be treated Wi, and the upper part is exposed to air. Note that at this time, the second pump P2 may be driven to circulate the water in the filter medium storage container 10.

(A22) In the biological filtration device 100 during normal operation at a low water level, as shown in FIG. Water to be treated Wi is discharged from the water supply port 30a of the water supply pipe 30. The water to be treated Wi flows in the direction of gravity from the top to the bottom of the aggregate of the filter media 20 while being filtered of impurities by physical action and attenuated by biological action by contacting the filter media 20. The water is drained into the drain pipe 40. Then, the water level L is stabilized at the same level as the low water level drain pipe 40L. Then, the entire assembly of filter media 20 is exposed to the air.

(A3) After a predetermined period of time has passed while the water filtration system S is in operation, the filter medium 20 is cleaned in order to restore the filtration function of the biological filtration device 100.
At this time, the first pump P is stopped. Then, as shown in FIG. 5, the low water level drain pipe 40L and the middle water level drain pipe 40M are closed. Although the high water level drain pipe 40H can be opened and closed at will, the high water level drain pipe 40H is closed here.
Then, a part B of the aggregate of filter media 20 is taken out from the filter media storage container 10 (removal step). Specifically, for example, approximately half of the entire assembly of filter media 20 is taken out from the outlet 15 provided on the side surface of the filter media storage container 10.

(A4) Then, as appropriate, as shown in FIG. 5, the filter medium storage container 10 is filled with water to a water level L above the top end 20t of the remainder A of the filter medium 20 assembly (water dipping step). On this occasion,

(A5) Next, the remainder A of the aggregate remaining in the filter medium storage container 10 is washed (cleaning step). At this time, the blower 11 is activated to blow air upward from the nozzle 12. As a result, a jet stream can be generated in the filter medium storage container 10, so that the remaining portion A can be effectively cleaned.

(A6) Next, as shown in FIG. 6, part B of the aggregate of the filter media 20 taken out in the previous dipping step is returned to the filter media storage container 10 and stacked above the remaining part A of the aggregate ( return process).

(A7) Then, the operation of the first pump P is restarted. That is, filtration of the water Wi to be treated by the water filtration system S is restarted.
In the biological filtration device 100 during normal operation at a medium water level, as shown in FIG. 6, the low water level drain pipe 40L is closed and the medium water level drain pipe 40M is left open. Although the high water level drain pipe 40H can be opened and closed as desired, the high water level drain pipe 40H is left open here.
In the biological filtration device 100 during normal operation at a low water level, as shown in FIG. 4, the low water level drain pipe 40L, the middle water level drain pipe 40M, and the high water level drain pipe 40H are left open.
Then, as shown in FIG. 6, the water to be treated Wi is discharged from the water supply port 30a of the water supply pipe 30 provided at the upper part of the filter medium storage container 10 of the biological filtration device 100. The water to be treated Wi flows in the direction of gravity from the top to the bottom of the aggregate of the filter media 20 while being filtered of impurities by physical action and attenuated by biological action by contacting the filter media 20. The water is drained into the drain pipe 40. In the case of normal operation at the medium water level, the water level L is stabilized at the same height as the medium water level drain pipe 40M. During normal operation at a low water level, the water level L is stabilized at the same level as the low water level drain pipe 40L. During normal operation at a medium water level, the lower part of the assembly of filter media 20 is immersed in the water to be treated Wi, and the upper part is exposed to air. During normal operation at a low water level, the entire assembly of filter media 20 is exposed to air. Here, the remaining part A of the aggregate of the filter media 20 is cleaned and the blockage caused by dead biofilm etc. is removed, and the physical filtration function has been recovered, but on the other hand, the biological filtration function has deteriorated. It has become. On the other hand, since part B of the aggregate of filter media 20 has not been washed, its physical filtration function is reduced, but its biological filtration function is maintained at a high level. Therefore, since part B of the aggregate of the filter medium 20 is located above the remaining part A, some of the microorganisms colonized in part B are transferred to the remaining part A due to the flow of the water to be treated Wi. can promote recolonization of microorganisms. Further, the upper part of the assembly of filter media 20 above the water level L can be exposed to the air and can receive the water to be treated Wi sprinkled from the water supply port 30a. Therefore, by supplying the filter medium 20 with plenty of air and the water to be treated Wi, the microorganisms fixed on the filter medium 20 can be activated. By doing so, the physical filtration function of the entire assembly of filter media 20 can be recovered, and the biological filtration function can be recovered quickly.

(Second embodiment)
Next, the biological filtration device 100 according to the second embodiment will be described in detail. Note that, hereinafter, descriptions of matters common to the biological filtration device 100 according to the first embodiment may be omitted.
FIG. 7 is a detailed diagram of the water supply pipe 30 of the biological filtration device 100 according to the second embodiment. 8 is a sectional view taken along arrow A in FIG. 7. FIG.

The biological filtration device 100 according to the second embodiment is not shown in FIG. 7, but as shown in FIG. , a filter medium 20 housed in the filter medium storage container 10, a water supply pipe 30 that supplies the water to be treated Wi to the filter medium storage container 10, and a drain pipe 40 that drains the treated water We from the filter medium storage container 10. , is equipped with.

The water supply port 30a of the water supply pipe 30 is located above the top end 20t of the assembly. The drain pipe 40 is located below the top end 20t. The biological filtration device 100 can maintain the water level L in the filter medium storage container 10 below the top end 20t.

Here, the water supply pipe 30 has a plurality of water supply ports 30a that open in different directions, as shown in FIGS. 7 and 8. Thereby, water discharged from the water supply port 30a can be evenly sprinkled over the top end 20t of the assembly.

The water supply port 30a may open upward, including diagonally upward. Thereby, the horizontal distance that water discharged from one water supply port 30a can reach can be increased, and the watering range can be expanded. Therefore, the water coming out of the water supply port 30a can be evenly sprinkled over the top end 20t of the assembly.

A plurality of water supply ports 30a may be provided along the extending direction of the water sprinkler pipe 32. This allows the area of watering to be expanded. The water supply ports 30a may be provided at regular intervals along the extending direction of the water sprinkling pipe 32, and the water supply ports 30a may be provided at irregular intervals along the extending direction of the water sprinkling pipe 32. It's okay to be rejected. The water supply ports 30a may be provided in one row along the extending direction of the water sprinkling pipe 32, or may be provided in two or more rows along the extending direction of the water sprinkling pipe 32.

The water supply pipe 30 includes a support pipe 31 and a water sprinkler pipe 32 that is supported by the support pipe 31 and extends substantially horizontally. Note that a plurality of sets of support pipes 31 and water sprinkler pipes 32 may be provided for one water supply pipe 30. The present invention is not limited to providing two water sprinkling pipes 32 for one support pipe 31, and one water sprinkling pipe 32 may be provided, or three or more water sprinkling pipes 32 may be provided. When having a plurality of water sprinkler pipes 32, the water spray pipes 32 may be arranged so that their extending directions are parallel, or may be arranged so that their extending directions are different.

The water sprinkler pipe 32 is a hollow pipe. The water sprinkler pipe 32 may be a straight pipe. One end of the water sprinkler pipe 32 is closed, and the other end is connected to the support pipe 31. The water sprinkler pipe 32 is provided with a plurality of water supply ports 32a.

As shown in FIG. 7, here, for example, a plurality of water supply ports 30a are provided for one water sprinkling pipe 32 at equal intervals in two rows along the extending direction of the water sprinkling pipe 32. The angle formed between each row of water supply ports 30a is approximately 90 degrees with respect to the axis g in a cross-sectional view perpendicular to the extending direction of the water sprinkler pipes 32.

As shown in FIG. 8, in a cross section perpendicular to the extending direction of the water sprinkler pipe 32, the water supply port 32a is connected to a vertical line G passing through the axis g (a line connecting the centroids of the cross section in the extending direction). , for example, it opens in a direction inclined at 45 degrees. Thereby, the flying distance of the water discharged from the water supply port 32a can be increased, and the watering range can be expanded.

The support pipe 31 rotatably supports the water sprinkler pipe 32. Thereby, the direction of the water supply port 30a provided in the water sprinkler pipe 32 can be changed. Therefore, the sprayed water can be adjusted to evenly spread over the top 20t of the assembly. Specifically, the support pipe 31 may be, for example, a T-shaped joint having three joints, so-called a cheese, used at a branch part of piping. The support pipe 31 has its first joint connected to the main water supply pipe 30 before branching. The support pipe 31 supports a pipe-shaped water sprinkler pipe 32 fitted in the second joint part. The support pipe 31 is supported with one pipe-shaped water sprinkler pipe 32 fitted in the remaining joint portion. Note that the support pipe 31 and the water sprinkler pipe 32 may be fitted together with their tapered surfaces, or may be fitted with a screw (appropriately a seal screw or a tapered screw).

Since the water sprinkler pipe 32 is rotatably supported with respect to the support pipe 31, when rotated about the axis g (for example, 180 degrees), the water supply port 32a opens in the direction shown in FIG. can be changed from upward (upper view in FIG. 8) to downward (lower view in FIG. 8). Therefore, the water sprinkling range can be adjusted according to the width of the top end 20t of the aggregate by the water sprinkling pipe 32 rotatably supported with respect to the support pipe 31.

Although the preferred embodiments of the present invention have been described in detail above, the biological filtration device, water filtration system, and water filtration method according to the present invention are not limited to the above-described embodiments, and are as described in the claims. Various modifications and changes are possible within the scope of the invention.

As described above, the biological filtration device 100 according to the embodiment supplies the filter medium storage container 10, the filter medium 20 accommodated in the filter medium storage container 10, and the water to be treated Wi to the filter medium storage container 10. It includes a water supply pipe 30 and a drain pipe 40 that drains the treated water We from the filter medium storage container 10. The filter medium 20 is an aggregate formed by stacking a plurality of granules. The water supply port 30a of the water supply pipe 30 is located above the top end 20t of the assembly. The drain pipe 40 is located below the top end 20t. The water level L in the filter medium storage container 10 can be maintained below the top end 20t. As a result, the upper part of the assembly of filter media 20 above the water level L in the filter media storage container 10 is exposed to the air and can receive the water to be treated Wi sprinkled from the water supply port 30a. can. Therefore, by abundantly supplying air and treated water Wi to the filter medium 20, microorganisms fixed on the filter medium 20 can be activated. Therefore, according to the biological filtration device 100, the physical filtration function can be recovered by cleaning the filter medium 20, and the biological filtration function can be recovered quickly, so that the water quality of the water flowing in the ring waterway C including the aquarium 200 can be maintained.

The water filtration system S according to the embodiment includes an aquarium 200 and a ring waterway C through which water in the aquarium 200 circulates. The ring waterway C branches into a first waterway C1 that returns to the aquarium 200 and a second waterway C2 that heads toward the biological filtration device 100. As a result, part B of the water to be treated from the water tank 200 flowing through the circular waterway C can be returned to the water tank 200, and the remaining part A can be directed to the biological filtration device 100, so that the flow rate of the water flowing through the circular waterway C and The flow rate can be maintained high and the load on the first pump P can be reduced. Therefore, the water filtration system S can maintain the quality of the water flowing through the circular waterway C including the water tank 200.

The filtration method according to the embodiment includes a taking-out process of taking out a part B of the aggregate from the filter medium storage container 10, a cleaning process of cleaning the remainder A of the aggregate remaining in the filter medium storage container 10, and a part of the aggregate. It includes a returning step of returning part B to the filter medium storage container 10 and stacking it above the remaining part A. Thereby, the physical filtration function of the aggregate of the filter media 20 as a whole can be recovered, and the biological filtration function can be recovered quickly. Therefore, with this filtration method, the quality of water flowing through the ring waterway C including the water tank 200 can be maintained.

10 Filter medium storage container 100 Biological filtration device 11 Blower 12 Nozzle 13 Perforated plate 14 Drain 20 Filter medium 200 Water tank 20b Lower end 20t Top end 30 Water supply pipe 31 Support pipe 32 Watering pipe 300 Physical filtration device 30a Water supply port 40 Drain pipe 400 Sterilizer 40H High water level drain pipe 40M Medium water level drain pipe 40L Low water level drain pipe 41 On-off valve C Circular waterway C1 First waterway C2 Second waterway L Water level P First pump P2 Second pump S Water filtration system We Treated water Wi Treated water G Axial center G Plumb line

Claims (8)

A filter medium storage container, a filter medium accommodated in the filter medium storage container, a water supply pipe that supplies water to be treated to the filter medium storage container, and a drain pipe that drains treated water from the filter medium storage container. , comprising;
The filter medium is an aggregate of a plurality of granules stacked together,
The water supply port of the water supply pipe is located above the top of the aggregate,
The drain pipe is below the top end,
The water level in the filter medium storage container can be maintained below the top end ,
the drain pipe is above the lower end of the aggregate;
The water supply port opens upward,
The drain pipes include a low water level drain pipe provided below the lower end, a medium water level drain pipe provided at a height midway between the top end and the bottom end, and a high water level drain pipe located above the top end. It has a water level drain pipe,
comprising an on-off valve that can switch the flow of drainage to the low water level drain pipe, the medium water level drain pipe, or the high water level drain pipe,
A blower that generates a jet of air in the filter medium storage container,
The water supply port has a plurality of water supply ports opening in different directions.
Biological filtration equipment. The water supply port opens upward, including diagonally upward.
Biological filtration device according to claim 1. The water supply pipe includes a support pipe and a water sprinkler pipe supported by the support pipe and extending substantially horizontally,
A plurality of the water supply ports are provided along the extending direction of the water pipe.
Biological filtration device according to claim 1 or claim 2. The support pipe rotatably supports the water sprinkler pipe.
Biological filtration device according to claim 3. comprising a water tank and a ring waterway through which water in the water tank circulates;
A water filtration system comprising a biological filtration device according to claim 1, wherein the ring waterway branches into a first waterway that returns to the aquarium and a second waterway that goes toward the biological filtration device. operating the on-off valve to open the low water level drain pipe and close the medium water level drain pipe and the high water level drain pipe to discharge the water to be treated from the water supply port;
With the low water level drain pipe and the medium water level drain pipe closed and the high water level drain pipe open, the blower is started to agitate the filter medium.
Water filtration method using the biological filtration device according to claim 1. a taking-out step of taking out a part of the aggregate from the filter medium storage container;
a cleaning step of cleaning the remainder of the aggregate remaining in the filter medium storage container;
The water filtration method using the biological filtration device according to claim 6 , comprising a return step of returning a part of the aggregate to the filter medium storage container and stacking it above the remaining part. Between the extraction step and the washing step,
8. The water filtration method according to claim 7, further comprising a dipping step of filling the remainder with water to a water level above the top of the remaining portion.

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