JPH09155391A - Biological water-treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain highly purified treated water efficiently in a relatively short time. SOLUTION: Raw water introduced into the inflow part 12 of a treatment tank 10 flows toward an outflow part 18. Numbers of screens 20 formed by filter cloth are arranged in the tank 10, which is divided into many treatment chambers 22. Therefore, the raw water is subjected to both biological treatment by microorganisms adherent to the filter cloth and filtration treatment during passage through the screen 20. A diffuser 34 is installed in each treatment chamber 22, an aerobic condition is maintained in the tank, and excessive microorganisms adherent to the screen 20 are peeled off automatically. Peeled sludge is discharged from the bottom. By the combination of multistage biological treatment, filtration treatment, precipitation and removal of sludge, high- grade treatment is performed efficiently.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biological water treatment device for purifying water to be treated by organisms attached to a screen.

[0002]

2. Description of the Related Art Hitherto, as one of biological water treatment apparatuses, there has been known an apparatus for biologically purifying treated water by allowing the treated water to pass through a filter medium to which microorganisms adhere.

For example, a contact aeration device is used in a domestic septic tank or the like. In this contact aeration apparatus, a filter medium is filled in the aeration chamber, and the water to be treated is circulated therein, and the water to be treated is aerobically purified by the microorganisms attached to the filter medium.

Further, for purification of river water, an inter-gravel purification device in which a flowing water channel is filled with gravel is used. In this gravel purification device, the water to be treated flowing through the gravel is purified by the organisms attached to the surface of the gravel.

Further, there is also known a biological filtration device in which microorganisms are made to adhere and grow on a filter medium for physically filtering the water to be treated, and the filtering action and biological purification are carried out simultaneously.

[0006]

In the conventional contact aeration apparatus, a sedimentation chamber is required to remove SS (buoyant solid matter) of microorganisms separated from the filter medium, which has little filtering effect. Further, in this settling chamber, the precipitated SS is likely to be in an anaerobic condition, so that the soluble organic matter is increased due to the decay of the precipitate, or the SS is easily scummed and flows out. Therefore, there is a problem that it is difficult to obtain highly purified treated water.

Further, the gravel purifying apparatus has a problem that it can be applied only to purifying relatively clean river water, etc., since it basically has no active supply of oxygen and its purifying ability is small. Further, if the water passage is deepened, the oxygen supply capacity per volume is reduced accordingly, so that the water passage cannot be deepened. Therefore, there is a problem that a large area is required to obtain sufficient purification capacity.

Further, since the biological filtration device performs physical filtration, it is immediately clogged, and there has been a problem that backwashing must be performed frequently. For example, when the diameter of the filter medium is reduced, the filtering action is performed in a thin area of the surface layer, and clogging occurs due to the attachment of organisms to the filter medium in this portion. Therefore, in order to remove this, backwashing is performed using the treated water. This back washing requires a considerable amount of water, and if it is performed frequently, the treatment efficiency will be greatly deteriorated. Further, when the diameter of the filter medium is made relatively large, there is a problem that the effect of physical filtration is reduced and a sufficiently high quality of water cannot be obtained. Further, even if the diameter of the filter medium is large, a thick biofilm is formed on the surface of the filter medium during the treatment, which requires backwashing with a large amount of water.

As described above, the conventional biological water treatment apparatus using a filter medium has a problem that it is impossible to efficiently obtain sufficiently advanced treated water. Therefore, there has been a demand for an apparatus capable of solving such a problem.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a biological water treatment apparatus which can efficiently obtain highly purified treated water in a relatively short time. And

[0011]

According to the present invention, there is an inflow part for inflowing treated water from one end side and an outflow part for outflowing treated water at the other end side to treat from the inflow part to the outflow part. A treatment tank that circulates water, and a screen that allows the water to be treated to flow from the inflow portion to the outflow portion while partitioning the treatment tank into a plurality of treatment chambers that are arranged at predetermined intervals in the treatment tank, The aeration means for aerating the water to be treated in the treatment tank, and the sludge storage part provided in the lower part of the treatment tank for storing the sludge to be settled, and the water to be treated is purified by the microorganisms adhering to and growing on the screen. It is characterized by doing.

As described above, the inside of the treatment tank is partitioned by the plurality of screens, and the water to be treated passes through the screens. Therefore, the water to be treated can be purified by the filtering action of the screen. Further, since the inside of the treatment tank is kept aerobic by the aeration means, aerobic microorganisms adhere to and propagate on the screen, and the aerobic microorganisms oxidize and remove organic substances in the water to be treated. Since this aerobic biological treatment is performed in multiple stages, it is possible to efficiently perform advanced treatment. Furthermore, by aeration,
Since the water to be treated is agitated, excess microorganisms on the screen are peeled off and stored in the sludge storage section. Therefore,
By appropriately discharging the sludge in the sludge storage section, the treatment in the treatment tank can be continued in a suitable state.

Further, a plurality of the screens are arranged in parallel in the processing tank with a gap of 50 mm or less, usually 5 mm to 50 mm, interposed therebetween. By arranging the screens at narrow intervals in this manner, the amount of microorganisms that can be retained in the treatment tank can be increased, and the treatment tank can be made compact. Also, sludge (microorganisms) can be effectively removed from the screen by the agitated flow due to aeration.

Further, the screen is characterized in that it is made of fibers having a minute diameter and is constituted by a filter cloth having a minute opening diameter.

By using such a screen, it is possible to reliably capture and remove the SS component in the water to be treated and the separated sludge, and to carry out a suitable filtration treatment. In addition, since the filter cloth is relatively soft, the movement of the filter cloth keeps the attached amount of SS below a predetermined level, and prevents clogging. Furthermore, by using fine fibers, the surface area of the filter cloth increases, the amount of microorganisms retained increases, and the amount of treatment can be increased. Furthermore, with such a filter cloth, clogging in the opening does not occur, so that good processing can be continued for a long time.

The opening diameter of the filter cloth is several μ to several tens.
It is characterized by being μ. With such a filter cloth,
The SS can be sufficiently captured and the sludge can be easily peeled off.

The surface area of the filter cloth is 1000 m ²
Characterized in that it is a ^{/ m 3 ~200000m 2 / m 3} . In this way, due to the large surface area of the filter cloth,
As described above, it is possible to secure a sufficient amount of microorganisms.

Further, each of the plurality of screens is characterized in that each substantially shields the flow of the water to be treated, and almost all of the flow of the treatment passes through the plurality of screens. With this configuration, the treated water can be maintained without being short-circuited and discharged.

Further, the aeration means is provided at the bottom of one or more processing chambers. As a result, aeration can be performed in each processing chamber, and desired oxygen can be supplied.

Further, the aeration means is characterized by performing aeration intermittently. As a result, the separated sludge can be effectively settled. It can also promote biological denitrification.

Further, it is characterized by having a coagulant adding means on the upstream side of at least one screen. Removal of phosphate is achieved by adding a coagulant such as an aluminum salt. In particular, since it is filtered by a screen, it is not necessary to form flocs after addition of the coagulant, and efficient treatment can be performed. Further, the concentration of the sludge can be increased.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment] [Structure] FIG. 1 is a sectional view showing a schematic structure of the entire apparatus as seen from the front side, and FIG. 2 is a sectional view as seen from the side. The treatment tank 10 has a substantially rectangular parallelepiped shape with an open upper surface, and stores a predetermined amount of water to be treated in the tank. An inflow portion 12 is provided on one end side (left side in the drawing) of the treatment tank 10, and the water to be treated is introduced into the treatment tank 10 from here. In this example, the river water pumped up by the pump 16 installed in the river 14 is supplied into the treatment tank 10 as the water to be treated through the inflow section 12. In addition, it is preferable that the inflow portion 12 be shaped like a weir, or that a baffle be provided here to uniformly supply the water to be treated into the treatment tank 10.

An outflow portion 18 is provided on the other end side (right side in the figure) of the treatment tank 10, and treated water is discharged from this outflow portion 18. The discharged treated water is returned to the river 14 or supplied to a water purification plant (not shown) as raw water. By returning to the river 14, the river can be purified, and if it is supplied to the water purification plant, the treatment in the water purification plant becomes easy. Further, the outflow portion 18 is preferably shaped like an overflow weir. That is, by using an overflow weir, it is possible to ensure a uniform outflow and set the water level in the treatment tank 10 to a predetermined level.

A plurality of water-permeable screens 20 are arranged in the processing tank 10 at predetermined intervals. In this example, the screens 20 are arranged at intervals of 10 mm, parallel to each other, and orthogonal to the flow of the water to be treated in the treatment tank 10 from the inflow portion 12 to the outflow portion 18. Then, as shown in FIG. 2, the screen 20 is arranged on the entire surface of the processing tank 10 so as to shield the processing tank 10. Therefore, the screen 20 divides and forms a plurality of processing chambers 22 in the processing tank 10.

Here, the screen 20 is formed of a cloth made of fine-diameter fibers and has a small thickness. For example, a polyamide nonwoven fabric having a fiber diameter of 15 μ and an opening diameter of 20 μ is used. Further, when such a screen 20 is installed in the processing tank 10, the screen 20 is fixed (eg, adhered) to a frame member made of hard plastic, and the frame member is fixed to the inner surface of the processing tank 20 (eg, bolted).
Then, the space between the inner surface of the processing tank 10 and the inner surface of the processing tank 10 may be sealed. Alternatively, a groove may be formed on the inner wall of the processing tank 10, and the frame member of the screen 20 may be fitted and fixed therein. When the cross-sectional area of the tank becomes large, the screen 20 may be appropriately reinforced or may be divided into a plurality of parts.

Further, the screen 20 usually extends above the water level in the processing tank 10. Therefore, the water to be treated in the treatment tank 10 does not pass above the screen 20. However, since the upper end of the screen 20 is formed lower than the upper surface of the treatment tank 10, even if the water to be treated exceeds the screen 20, it does not overflow from the treatment tank 10.

The bottom of the treatment tank 10 is in the form of two rows of triangular grooves (hopper shape) along the direction of water flow, and below the screen 20 is a water-permeable material that closes this hopper-shaped portion. A partition plate 24 having no property is provided. Therefore, each processing chamber 22 is separated from the adjacent processing chamber 22 by the screen 20 on the upper side and the partition plate 24 on the lower side.

As described above, the hopper-shaped bottom of each processing chamber 22 is partitioned by the partition plate 24 having no water permeability. Therefore, this part is kept relatively static,
It is a sludge storage unit 26 in which sludge settles and accumulates. A sludge drawing pipe 32 having an on-off valve 30 is connected to the bottom of the sludge storage unit 26.
By opening 0, the sludge accumulated in the sludge storage section 26 can be appropriately withdrawn.

An on-off valve may be attached to each branch pipe upstream of the on-off valve 30 and communicating with each processing chamber 22.

The lower portion of each processing chamber 22 (screen 2
An air diffuser 34 is arranged above the lower end of 0 or at the boundary between the screen 20 and the partition plate 24). The air diffuser 34 is connected to a blower 36, and air is supplied from the air diffuser 34 into each processing chamber 22 to perform aeration. The air diffuser 34 does not necessarily have to be arranged in all the processing chambers 22.
It may be arranged only in the processing chamber 22 on the side close to. Further, it is preferable that the air diffuser 34 can individually control the air diffuser. The air diffuser 34 for performing air diffusion may be switched at predetermined time intervals.

[Treatment Operation] In such an apparatus, when treatment is performed, the pump 16 is driven to supply the water to be treated to the inflow section 12. It is also preferable to remove relatively coarse dust such as plastic products and dead leaves by using a fine screen or the like before supplying to the inflow section 12. Further, a fine screen may be arranged at the suction port of the pump 16.

Here, at least the half (first half) of the processing chamber 22 on the side close to the inflow portion 12 is constantly aerated by the air diffuser 34. Therefore, the inside of the processing tank 10 is always maintained in an aerobic state.

"Screen function" and the processing tank 10
The untreated water supplied to the untreated water passes through the screen 20 and is discharged from the outflow section 18. Therefore, it is filtered by the screen 20. Therefore,
The SS contained in the water to be treated is sequentially captured by each screen 20.

On the other hand, since the inside of the processing tank 10 is maintained in an aerobic state as described above, aerobic microorganisms propagate and multiply on the surface of the screen 20. Screen 20
Since it is formed of the cloth as described above, its surface area is large, and a relatively large amount of microorganisms adhere and grow on this surface.
Then, these microorganisms oxidize and decompose BOD (biochemical oxygen demand) components and the like in the water to be treated.

Here, the screens 20 are arranged in multiple stages. Therefore, the water to be treated is sequentially purified by the screens 20, and the treated water discharged from the outflow portion 18 is highly purified. In particular, the screen 20 has both a biological cleaning action and a physical filtration action, so that a very effective treatment is achieved.

Since the water to be treated is purified by sequentially passing through the screen 20 as described above, the load on the treatment chamber 22 is larger on the side closer to the inflow section 12. Therefore, the amount of growth of microorganisms is larger in the screen 20 on the inflow section 12 side. However, the screen 20 according to the present embodiment is arranged at intervals of 10 mm, and since the area is aerated, the inside thereof is sufficiently agitated and the screen 20 is not clogged.

Further, the screen 20 of the present embodiment is very thin and is slightly deformed during processing. This also promotes the separation of sludge and prevents clogging of the screen 20. Furthermore, when a thin filter cloth is used, the SS is captured only on the surface portion thereof, so that the SS does not enter the opening of the screen 20 and become clogged (the SS reaching the inside of the opening passes). . So screen 2
It is possible to effectively prevent 0 clogging.

On the inflow side, the load of the substance to be removed such as organic matter is high, so it is necessary to prevent the occurrence of clogging. On the other hand, in the latter stage, there is little concern about clogging, and we want to make SS filtration more precise. Therefore, a thin filter cloth is used as the screen 20 on the inflow side, and a thick filter cloth or a multi-membrane is used on the downstream side to increase the SS capturing ability and increase the surface area for biological attachment. Then, the treatment effect can be enhanced.

"Aeration method" Further, since the load such as BOD component is higher on the inflow side, the oxygen demand is higher. Therefore,
It is also preferable to increase the amount of aeration on the inflow side compared to the outflow side. Further, due to this aeration, the processing chamber 22 is
A stirring flow is generated, the separation of sludge from the surface of the screen 20 is promoted, uniform filtration (water passage) by the entire screen 20 can be maintained, and a sufficient treatment effect can be maintained.

Ordinary aeration may be performed intermittently. For example, by dividing the air diffuser 34 into two groups and alternately performing aeration, it is possible to sufficiently settle the sludge in the portion where aeration is not performed.

Incidentally, it is possible to provide a processing chamber 22 which mainly performs precipitation and filtration without aeration under normal conditions. Further, the air diffuser 34 may be provided at a relatively upper part of the processing chamber 22 to accelerate the precipitation process in the lower part.

"Treatment of sludge" The sludge separated from the screen 20 is accumulated in the sludge storage section 26 which is not aerated. Therefore, by opening the opening / closing valve 30 at an appropriate interval (for example, once a day) and pulling out a desired amount of sludge, the clogging of the screen 20 is prevented and the biological treatment is favorably continued. Further, since the generated sludge amount is large on the inflow portion 12 side, it is preferable to increase the sludge withdrawal amount on the inflow portion 12 side. In this embodiment, four sludge extraction pipes 32 are grouped together and connected to one on-off valve 30.
The four sludge storage units 26 are grouped in the order of the flow direction within 0. Therefore, the on-off valve 30 on the inflow section 12 side
It is advisable to adjust the amount of sludge drawn out by increasing the frequency with which the sludge is opened or increasing the opening time.

Here, the screen 20 may be cleaned by periodically increasing the aeration amount of a part of the processing chamber 22. In this way, the separated sludge can be extracted in the same manner. At this time, since the treatment by the screen 20 in the subsequent stage is performed, the treated water is not adversely affected. If the processing chamber 22 is sequentially cleaned, the blower 36 can be used for cleaning. Also, by stopping the aeration after washing, sludge can be precipitated and extracted.

[Removal of Phosphoric Acid] In the above-mentioned treatment, phosphorus is removed only from phosphorus contained in the drawn-out sludge. In order to remove phosphate more efficiently,
It is effective to add a coagulant. It has been conventionally known that a phosphate salt can be aggregated and precipitated by aluminum ion and calcium ion, and it is preferable to add an aggregating agent to water to be treated. As the coagulant, aluminum sulfate, polyaluminum chloride (PAC) and the like are suitable. Such a flocculant becomes flocs combined with the phosphate in the processing chamber 22, and the flocs are mixed with the screen 2
Captured to 0. Therefore, the phosphate salt can be coagulated and filtered. The collected coagulated sludge is extracted and discharged together with other sludge.

In particular, since the screen 20 has a mesh size of several μ, it is possible to efficiently capture the agglomerated flocs that are produced and achieve a high degree of phosphorus removal. In this way, since phosphorus can be removed simultaneously in the same tank, no special device is required, the device can be made compact as a whole, and space can be saved. Further, since flocculation flocs are removed by filtration through the screen 20, stirring for flocculation is unnecessary, and back washing is also unnecessary.

When injecting a chemical (coagulant), it is possible to provide a partition plate with one hole in the tank and inject the chemical into the flow of water to be treated flowing out from this hole. .

By adding a coagulant, the concentration of the settled sludge can be increased, the volume of drawn sludge can be reduced, and the post-treatment can be simplified. In addition,
A polymer flocculant may also be added to accelerate the flocculation of sludge.

"Denitrification" When sufficient BOD oxidation is carried out,
Oxidation (nitration) of nitrogen components also occurs. Therefore, biological denitrification can be promoted by performing intermittent aeration and locally generating an anaerobic condition. by this,
The removal rate of nitrogen can be improved. Further, denitrification can be almost completely performed by adding methanol to the processing chamber 22 in the latter stage and not performing or reducing the aeration there. A re-aeration chamber similar to the other processing chambers is provided after the denitrification chamber.

"Removal of algae" Furthermore, in this way, BO
When the D component is sufficiently removed by oxidation, nitrification, and denitrification to purify the water quality, minute metazoa such as ringworms naturally occur on the screen 20 in the subsequent stage. Since these minute metazoans prey on minute algae, etc., minute algae that are difficult to remove by ordinary treatment are also removed, and treated water with extremely high transparency can be obtained.

"Effect" In the apparatus of this embodiment, the following treatment results were obtained under the conditions that the raw water was river water, the treatment tank 10 had a residence time of 2 hours, and the water temperature was 20 ° C.

Raw water quality, BOD: 50 mg / l, SS:
50mg / l, T-N: 15mg / l, T-P ( total phosphorus): 3 mg / l, _{algae: 3mg / l, NH 4 -N} ( ammonia nitrogen): 10 mg / l to treated water quality,
BOD: 2 mg / l or less, SS: 2 mg / l or less, T-
N: 3 mg / l or less, T-P: 0.5mg / l or less, algae: 0.01 mg / l or less, NH ₄ -N: 0.1mg /
Less than 1 was obtained.

As described above, according to the apparatus of this embodiment,
It is understood that a very high degree of purification treatment can be achieved.
Therefore, this apparatus can suitably purify polluted lakes, seas, and rivers, and treat domestic wastewater, sewage, organic factory wastewater, and the like. In particular, since basically no chemicals are used, there is no secondary pollution to the environment, and space-saving and economical treatment can be achieved. In addition, maintenance and management basically requires only the removal of sludge, and has the advantage that no special management is required.

"Another Configuration Example" FIGS. 3 and 4 are schematic diagrams of a front cross section and a side cross section showing another configuration example.
In this example, the screen 20a in the first half is a thin film filter cloth similar to the above-mentioned example, while the screen 20b in the latter half is a thick film filter cloth. Therefore, in the first half of the high-load treatment tank 10, the high-load treatment can be performed while suppressing the clogging of the screen 20a, and the high-level treatment can be achieved in the second half of the low-load. Furthermore, the width of the processing chamber 22 in the first half (the interval between the screens 22a) is the same as the above example, but the width of the processing chamber 22 in the processing chamber 22 in the latter half (the interval between the screens 22b) is set wider. is there. Therefore, in the first half, under a high load and a relatively large amount of sludge generated, clogging is prevented and effective treatment is performed, and in the second half, sufficient filtration and sufficient treatment with sufficient biomass are achieved. be able to.

Further, in this example, a horizontal bottom plate 40 is provided at the bottom of the processing tank 10. The bottom plate 40 has a large number of sludge circulation holes 42 of a predetermined diameter in the portion corresponding to each processing chamber 22. A hopper-shaped sludge storage chamber 44 is provided below each processing chamber 22. The sludge storage chamber 44 is partitioned by a bottom partition plate 46 for each of the four processing chambers 22 in this example. Therefore, one sludge storage chamber 44 and four treatment chambers 22 are connected to the sludge flow holes 42.
Is connected through. An on-off valve 30 is connected to each sludge storage chamber 44 via a sludge drawing pipe 32. Therefore, the sludge accumulated at the bottom of the processing chamber 22 is sludge circulation hole 4
It is possible to withdraw the accumulated sludge at any time by accumulating in the sludge storage chamber 44 via 2 and opening the on-off valve 30.

An upper partition plate 48 is provided above each bottom partition plate 46. This upper partition 4
Reference numeral 8 denotes a portion that slightly protrudes upward from the bottom of the processing chamber 22, and when sludge is drawn out from the sludge storage chamber 44, a strong flow along the bottom plate 40 from the bottom of the adjacent processing chamber 22 is generated. This is to prevent it from occurring.

As described above, according to this embodiment, since the screen 20 is changed between the first half and the second half, each processing chamber 22 is changed.
The effective processing according to the load can be performed. Also,
By increasing the volume of the treatment chamber 22 in the latter half, it is possible to appropriately treat the low-concentration water to be treated with gentle aeration. Further, since the sludge storage chamber 44 having a relatively large size is provided, the sludge drawing pipe 32 is simplified. Further, the separated sludge settled in the sludge storage chamber 44 through the sludge circulation hole 42 of the bottom plate 40 is stored in the sludge storage chamber 44, and the sludge can be efficiently removed.

[0058]

EXAMPLES The results of experiments actually conducted using the apparatus of the embodiment shown in FIG. 3 are shown below. (Conditions) Processing tank dimensions: width 50 cm x height 100 cm x length 100
cm (Note that the height of the treated portion, that is, the water depth was 50 cm.), treatment flow rate: 125 l / hour, screen (filter cloth) dimensions: width 50 cm x height 60 cm x
Thickness 0.7 mm × 80 layers (In addition, since the 40 layers in the latter half are 5 layers of multi-layered membrane, the filter cloth of 40 sheets in the first half and 200 sheets in the latter half are used), the specification of the filter cloth: thickness −0. 7 mm, material-polyamide, fiber diameter-average 15μ, surface area-60,000 m2 / m3,
Opening diameter -20μ, porosity 84%.

(Processing Result) The processing result is shown in Table 1.

[0060]

[Table 1] The COD (chemical oxygen demand) is CODMn using permanganate.

Next, in the treatment experiment, each stage (treatment chamber 2
The water quality (SS) in 2) was investigated. This result is shown in FIG.
Shown in Thus, it can be seen that almost enough removal is completed in about 40 steps. The high SS concentration in the 30th stage is considered to be due to the large amount of nitrifying bacteria generated in the processing chamber 22.

Furthermore, ammonia (NH ₄
N), nitric acid (NO ₃ -N), total phosphorus (TP) water quality survey results are shown in FIG. 6. As described above, most of the treatment is completed in about 40 stages, but the nitrification is still progressing thereafter.
It is speculated that this is because the bacteria involved in nitrification are autotrophic bacteria and continue to oxidize a trace amount of ammonia originating from organisms even after being highly purified.

Further, a considerable amount of nitric acid remains in the treated water. This is presumably because during this treatment, the inside of the treatment tank was maintained in an aerobic state, and denitrification did not occur much.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a schematic configuration of an embodiment.

FIG. 2 is a side sectional view showing a schematic configuration of an embodiment.

FIG. 3 is a front sectional view showing a schematic configuration of another configuration example.

FIG. 4 is a side sectional view showing a schematic configuration of another configuration example.

FIG. 5 is a characteristic diagram showing changes in SS water quality in a treatment tank.

FIG. 6 is a characteristic diagram showing changes in water quality of nitrogen and phosphorus in the treatment tank.

[Explanation of symbols]

10 treatment tank, 12 inflow part, 18 outflow part, 20 screen, 22 processing chamber, 26 sludge storage part, 30 on-off valve, 34 air diffuser, 40 bottom plate, 42 sludge distribution hole, 44 sludge storage chamber.

[Procedure amendment]

[Submission date] November 14, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 1

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claim 7

[Correction method] Change

[Correction contents]

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] Claim 10

[Correction method] Change

[Correction contents]

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction contents]

[0011]

Means for Solving the Problems The present invention is, toward the outlet section from the inflow section has an outlet portion for discharging the treated water at the other end has an inlet portion for introducing the water to be treated from one end side to be A treatment tank which circulates the treated water, and a plurality of screens which are arranged in the treatment tank at predetermined intervals to partition the inside of the treatment tank into a plurality of treatment chambers and through which the water to be treated flowing from the inflow portion to the outflow portion passes. Aeration means for aerating the water to be treated in the treatment tank,
And a sludge storage unit which stores sludge settled in the lower part of the treatment tank, and purifies the water to be treated by microorganisms adhering to and growing on the screen.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction contents]

Further, the plurality of screens are for the treated water.
Wherein the the almost total amount is arranged to over-passing. With this configuration, the treated water can be maintained without being short-circuited and discharged.

[Procedure correction 6]

[Document name to be amended] Statement

[Name of item to be corrected] 0025

[Correction method] Change

[Correction contents]

A plurality of water-permeable screens 20 are arranged in the processing tank 10 at predetermined intervals. In this example, the screens 20 are arranged at intervals of 10 mm, parallel to each other, and orthogonal to the flow of the water to be treated in the treatment tank 10 from the inflow portion 12 to the outflow portion 18. Then, as shown in FIG. 2, the screen 20 so as to shut off the flow of the water to be treated in the treatment tank 10,
It is placed on the entire surface. Therefore, the screen 20
Thus, a plurality of processing chambers 22 are formed in the processing tank 10.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0027

[Correction method] Change

[Correction contents]

[0027] The screen 20 extends from the normal water level in the treatment tank 10 to the upper. Therefore, the water to be treated in the treatment tank 10 does not pass above the screen 20. However, since the upper end of the screen 20 is formed lower than the upper surface of the treatment tank 10, even if the water to be treated exceeds the screen 20, it does not overflow from the treatment tank 10.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction contents]

The bottom of the processing tank 10 is in the form of two rows of triangular grooves (hopper shape) along the direction of water flow. Below the screen 20, a plurality of hopper-shaped portions are provided .
A partition plate 24 that is impermeable to water and is partitioned into chambers is provided. Therefore, the upper part of each processing chamber 22 is the screen 20,
The lower part is separated from the adjacent processing chamber 22 by a partition plate 24.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0031

[Correction method] Change

[Correction contents]

The lower portion of each processing chamber 22 (screen 2
An air diffuser 34 is arranged above the lower end of 0 or at the boundary between the screen 20 and the partition plate 24). The air diffuser 34 is connected to a blower 36, and air is supplied from the air diffuser 34 into each processing chamber 22 to perform aeration. The air diffuser 34 does not necessarily have to be arranged in all the processing chambers 22.
It may be arranged only in the processing chamber 22 on the side close to. Further, it is preferable that the air diffuser 34 can individually control the air diffuser, and the air diffuser 34 for performing the air diffuser may be switched at predetermined time intervals.

[Procedure amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0034

[Correction method] Change

[Correction contents]

"Screen function" and the processing tank 10
The treated water supplied inside passes through the screen 20,
It is discharged from the outflow section 18. Therefore, the screen 20
Is filtered by. Therefore, the SS contained in the water to be treated is sequentially captured by each screen 20.

[Procedure amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0038

[Correction method] Change

[Correction contents]

Further, the screen 20 of the present embodiment is very thin and is slightly deformed during processing. This also promotes the separation of sludge and prevents clogging of the screen 20. Furthermore, when a thin filter cloth is used, the SS is captured only on the surface portion thereof, so that the SS does not enter the opening of the screen 20 and become clogged (the SS reaching the inside of the opening passes). . So screen 2
0 of clogging can be effectively prevented.

[Procedure amendment 12]

[Document name to be amended] Statement

[Correction target item name] 0043

[Correction method] Change

[Correction contents]

"Treatment of sludge" The sludge separated from the screen 20 is accumulated in the sludge storage section 26 which is not aerated. Therefore, by opening the opening / closing valve 30 at an appropriate interval (for example, once a day) and pulling out a desired amount of sludge, the clogging of the screen 20 is prevented and the biological treatment is favorably continued. Further, since the generated sludge amount is large on the inflow portion 12 side, it is preferable to increase the sludge withdrawal amount on the inflow portion 12 side. In the present embodiment, the sludge drawing pipes 32 are grouped in groups of five and connected to one on-off valve 30.
The four sludge storage units 26 are grouped in the order of the flow direction within 0. Therefore, the on-off valve 30 on the inflow section 12 side
It is advisable to adjust the amount of sludge drawn out by increasing the frequency with which the sludge is opened or increasing the opening time.

[Procedure amendment 13]

[Document name to be amended] Statement

[Correction target item name] 0054

[Correction method] Change

[Correction contents]

"Another Configuration Example" FIGS. 3 and 4 are schematic diagrams of a front cross section and a side cross section showing another configuration example.
In this example, the screen 20a in the first half is a thin film filter cloth similar to the above-mentioned example, while the screen 20b in the latter half is a thick film filter cloth. Therefore, in the first half of the high-load treatment tank 10, the high-load treatment can be performed while suppressing the clogging of the screen 20a, and in the latter half of the low-load treatment, the high-level treatment can be achieved. Furthermore, the width of the first half of the processing chamber 22 (distance scree <br/> down 20 a) is the same as the above example, the second half of the
The width of processing chamber 22 (distance of the screen 20 b) is is set wider. Therefore, in the first half, under a high load and a relatively large amount of sludge generated, clogging is prevented and effective treatment is performed, and in the second half, sufficient filtration and sufficient treatment with sufficient biomass are achieved. be able to.

[Procedure Amendment 14]

[Document name to be amended] Statement

[Correction target item name] 0055

[Correction method] Change

[Correction contents]

Further, in this example, a horizontal bottom plate 40 is provided at the bottom of the processing tank 10. The bottom plate 40 has a large number of sludge circulation holes 42 of a predetermined diameter in the portion corresponding to each processing chamber 22. A hopper-shaped sludge storage chamber 44 is provided below each processing chamber 22. In this example, the sludge storage chamber 44 is divided into four processing chambers 22 in the first half of the processing tank 10 and two processing chambers 22 in the second half by a bottom partition plate 46. Therefore, four or two treatment chambers 22 are connected to one sludge storage chamber 44 through the respective sludge circulation holes 42. An on-off valve 30 is connected to each sludge storage chamber 44 via a sludge drawing pipe 32. Therefore, the sludge accumulated at the bottom of the processing chamber 22 is accumulated in the sludge storage chamber 44 through the sludge circulation hole 42 and the on-off valve 30 is opened, so that the accumulated sludge can be withdrawn at any time.

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location C02F 3/10 C02F 3/12 A 3/12 3/20 C 3/20 B01D 23/02 A

Claims (10)

[Claims] 1. A treatment tank having an inflow part for inflowing treated water from one end side, an outflow part for outflowing the treated water at the other end side, and circulating the treated water from the inflow part to the outflow part. A plurality of screens are arranged in the treatment tank at predetermined intervals to partition the inside of the treatment tank into a plurality of treatment chambers, and to pass the water to be treated flowing from the inflow portion to the outflow portion, and the screen in the treatment tank. An aeration means for aerating the water to be treated, and a sludge storage part provided in the lower part of the treatment tank for storing the sludge to be settled, and purifying the water to be treated by the microorganisms adhering to and growing on the screen. Characteristic biological water treatment equipment. 2. The biological water treatment apparatus according to claim 1, wherein a sludge drawing pipe is connected to the sludge storage section. 3. The biological water treatment apparatus according to claim 1, wherein a plurality of the screens are arranged in parallel in a treatment tank with a gap of 50 mm or less. . 4. The device according to claim 1, 2 or 3, wherein the screen is formed of a fiber having a minute diameter and is composed of a filter cloth having a minute opening diameter. Water treatment equipment. 5. The biological water treatment apparatus according to claim 4, wherein the filter cloth has an opening diameter of several μm to several tens of μm. 6. The apparatus according to claim 4 or 5, wherein the surface area of the filter cloth is 1000 m ² / m ^{3 to} 20000.
A biological water treatment device, which is 0 m ² / m ³ . 7. The apparatus according to any one of claims 1 to 6, wherein each of the plurality of screens substantially blocks the flow of water to be treated, and substantially the entire amount of the flow of treatment is plural. Biological water treatment device, characterized by passing through a screen of. 8. The biological water treatment apparatus according to any one of claims 1 to 7, wherein the aeration means is provided in a lower portion of one or more treatment chambers. 9. The biological water treatment apparatus according to claim 8, wherein the aeration means performs aeration intermittently. 10. The biological water treatment apparatus according to claim 1, further comprising an aggregating material adding unit on the upstream side of at least one screen.