JP6740410B1 - Sewage treatment method and sewage treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sewage treatment method and a sewage treatment apparatus for crushing impurities contained in sewage to a suitable size and cutting. SOLUTION: Sewage is caused to flow into a biaxial crushing device to crush the foreign substances to form a first foreign substance, and a crushing step of obtaining a first treatment liquid 38; And a cutting step of using the second treatment liquid 39 as a second contaminant, and the biaxial crushing device is a device that crushes the contaminants while sandwiching them to obtain the first contaminants. Is a cutting blade 35 held by a holder that rotates around a rotation axis in the flow direction of the first treatment liquid 38, and has a plurality of permeation holes that intersect with the flow direction of the first treatment liquid 38 and face each other. A plate 34, and the cutting step is performed by rotating the cutting blade 35 in a facing state in which the cutting blade 35 is close to or in contact with the facing plate 34 to cut the first contaminant into a second contaminant, and to pass through the permeation hole. A sewage treatment method and a sewage treatment apparatus, which are the second treatment liquid 39. [Selection diagram] Figure 8

Description

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

BACKGROUND ART Conventionally, sewage such as domestic effluent, business effluent, and factory effluent is drained to a sewer pipe, and collected and treated at a sewage treatment plant via a relay pump station and a sewer trunk line. The treated water is discharged into rivers and the sea.

The drained sewage includes, for example, plastics, underwear, rags, fibers such as absorbent cotton, and various foreign substances such as waste cloth, toilet paper, and hair. These contaminants cannot be discharged into rivers or the sea together with the water treated at the sewage treatment plant, and are collected by screen equipment installed in a sand basin at a relay pump station or a sewage treatment plant, for example. Treated as waste.

In recent years, there is a tendency to consolidate wastewater other than conventional sewage at sewage treatment plants and promote treatment by making effective use of energy and taking advantage of the scale of sewage treatment plants. Here, as the sewage other than the conventional sewage, for example, sewage of septic tanks, agricultural/fishery village drainage facilities, etc., may include garbage, industrial waste, and diaper pieces.

By promoting the integrated treatment at this sewage treatment plant, the amount of contaminants flowing into the sewage treatment plant tends to increase.

In a sewage treatment plant, an increase in contaminants causes various problems in tanks (ponds) and equipments provided in each step of sewage treatment.

Therefore, to increase the amount of contaminants, it is possible to employ a method of suppressing defects by crushing the contaminants to a suitable size.

Patent Literature 1 and Patent Literature 2 are disclosed as a technique for crushing impurities. Patent Document 1 relates to a device provided with a first crushing means, a receiving water tank, and a second crushing means, and is a technique of crushing solid foreign matters such as residue by these crushing means. However, since these crushing means crush the solid foreign matter by the pair of upright crushing units, the crushed material is stretched in a strip shape without being cut. Then, the crushed material may adhere to the tank (pond) or the equipment and may be entangled with each other, causing a problem.

Patent No. 5336266 Special Table 2012-521285 Japanese Patent Publication No. 2013-537103

A main problem to be solved by the present invention is to provide a sewage treatment method and a sewage treatment apparatus for crushing impurities contained in sewage to a suitable size and cutting.

The representative aspects of the present invention which have solved the above problems are as follows.

<First mode>
A crushing step of causing sewage to flow into a biaxial crushing device, crushing impurities contained in the sewage into first impurities, and obtaining a first treatment liquid containing the first impurities;
A step of causing the first treatment liquid to flow into a cutting device, cutting the first contaminants to form second contaminants, and a second treatment liquid containing the second contaminants,
The biaxial crusher is
A device having two rotating shafts arranged in parallel with a crushing blade in a peripheral portion, and crushing while sandwiching the contaminants with these rotating shafts to obtain the first contaminants,
The cutting device includes a cutting blade held by a holder that rotates around a rotation axis of a flow direction of the first processing liquid in the flow of the first processing liquid, and intersects the flow direction of the first processing liquid. Provided with an opposing plate having a plurality of transmission holes,
In the cutting step, the cutting blade is rotated in a facing state in which the cutting blade is close to or in contact with the facing plate, the first contaminant is cut into the second contaminant, and the transmitting hole of the facing plate is permeated. As the second processing liquid,
A sewage treatment method characterized by the above.

Contaminants contained in the sewage can be collected, for example, by screen equipment installed at relay pump stations and sand basins, but the contaminants that pass through the screen equipment are treated at the downstream facilities or processing equipment. It adheres to and is entangled with the water and has a serious effect on the operation of the treatment facility. When the sewage containing this foreign matter was made to flow into the two-axis crushing device, the foreign substances sandwiched between the rotating shafts were crushed, and as a result, the crushed first foreign matter and the crushed non-crushed two-way crushing device passed through. A first treatment liquid containing a small-sized contaminant is obtained. The thickness of the first contaminant is approximately the same as the width between the rotation axes. However, among the first contaminants, there are those which are long but have a long thread-like shape or a band-like shape. Therefore, the first treatment liquid containing the first contaminant is sent to the cutting device, and the cutting blade provided in the cutting device is rotated in a facing state in which the cutting blade is close to or in contact with the facing plate to cut the first contaminant. Then, since the contaminants contained in the second treatment liquid are composed of a suitable size that has passed through the biaxial crushing device and the cutting device, the treatment facility and treatment equipment provided downstream, and these It is possible to prevent the burrs from being attached or entangled.

Among the impurities sent to the cutting device, the impurities having a size that cannot pass through the permeation holes of the facing plate remain on (hang on) the facing plate. The foreign matters remaining (hooked) on the facing plate are cut by the rotation of the cutting blade. The contaminants remaining on the facing plate are cut and penetrate the permeation holes along the sewage flow.

If the contaminants remain attached to the facing plate, depending on the sewage to be treated, the contaminants gradually accumulate on the facing plate due to continuous or intermittent inflow of the first treatment liquid, and solidify or enlarge, There is a risk of blocking the facing plate. When the cutting blade is rotated in a facing state in which the cutting blade is close to or in contact with the facing plate, the cutting blade scrapes off contaminants attached to the facing plate. As a result, it is possible to prevent impurities from accumulating on the facing plate.

<Second mode>
The biaxial crushing device is for crushing the impurities to obtain a first impurity having a thickness of 10 mm or less,
The said cutting device can mention the aspect which cut|disconnects the said 1st foreign substance and makes it a 2nd foreign substance with a length of 50 mm or less.

Since these devices can obtain contaminants with a thickness of 10 mm or less and a length of 50 mm or less, the obtained contaminants are attached to and entangled in the downstream processing facilities and processing equipment and their burrs. This has the effect of further suppressing

<Third aspect>
The cutting device has an inflow part for inflowing the first processing liquid,
An aspect in which the facing plate is provided so that an angle formed by the facing plate and an inflow direction of the first processing liquid in the inflow portion of the cutting device is an acute angle can be mentioned.

Since the facing plate has an acute angle with respect to the flow direction of the first processing liquid in the inflow portion of the cutting device, the transmission hole also has an acute angle. When the facing plate is provided in this manner, it becomes difficult for foreign matters to pass through the permeation holes, and the foreign substances are easily caught and retained by the facing plate. Not only a relatively long contaminant but also a relatively small contaminant is likely to stay in the facing plate, so that the contaminant can be finely cut.

<Fourth aspect>
An embodiment in which the first treatment liquid flowing out from the biaxial crushing device reaches the cutting device within 60 seconds can be mentioned.

The first treatment liquid contains the first contaminant crushed by the crushing device. If the first contaminant is left uncut for a while, the first contaminant will be deformed or aggregated again into a large lump, which makes it difficult to cut with the cutting device. Therefore, by setting the time for the first treatment liquid to reach the cutting device to be within 60 seconds, it is possible to prevent the deformation and re-aggregation of impurities and to make it easy to cut with the cutting device. ..

<Fifth aspect>
A sewage treatment device for crushing and cutting impurities contained in inflowing sewage,
The sewage treatment device,
A biaxial crushing device for crushing impurities to obtain first impurities and obtaining a first treatment liquid containing the first impurities;
A cutting device for cutting the first contaminant to obtain a second contaminant and obtaining a second treatment liquid containing the second contaminant,
The biaxial crushing device is provided with two rotary shafts arranged in parallel with a crushing blade in the peripheral part, and crushes the foreign substances while sandwiching the rotary shafts to form the first foreign substance. Yes,
The cutting device includes a cutting blade held by a holder that rotates around a rotation axis of a flow direction of the first processing liquid in the flow of the first processing liquid, and intersects the flow direction of the first processing liquid. And a counter plate having a plurality of permeation holes, and the cutting blade is rotated in a facing state in which the cutting blade is close to or in contact with the counter plate to cut the first contaminant and the second contaminant. It is a thing,
A sewage treatment device characterized by the above.

According to the present invention, the impurities contained in the sewage are crushed and finely cut, so that problems such as adhesion to the sewage treatment facility or treatment equipment, entanglement, and clogging can be suppressed.

It is a figure which shows a biaxial crushing apparatus. It is a figure which shows the biaxial crushing apparatus of another embodiment. It is explanatory drawing which sewage passes through a crushing disk group. It is explanatory drawing of a cutting device. It is a figure which shows the principal part of crushing of a cutting device. It is a figure which shows an example of an opposing plate. It is a figure which shows another form of a cutting device. It is a figure which shows a processing flow. It is an explanatory view of an angle formed by a facing plate and an inflow direction of the first processing liquid in the inflow portion.

Modes for carrying out the present invention will be described. The present embodiment is an example of the present invention.

(Sewage treatment facility)
The sewage discharged from households and business sites flows into the sewer pipes and the sewer trunk line from sewage, and also flows into the sewage treatment plant via the relay pump station. The sewage that has flowed into the sewage treatment plant is discharged to the outside of the system through, for example, a sand basin, a first settling basin, a reaction tank, a final settling basin, and a chlorine admixture. Sludge (raw sludge) that has settled to the bottom of the pond in the first settling tank and activated sludge that settled to the bottom of the pond in the final settling tank are temporarily stored in the sludge storage tank and mixed. Then, the volume of the mixed sludge is reduced by concentration, dehydration, incineration, etc. in a sludge treatment facility. Each processing facility such as the first settling tank, reaction tank, final settling tank, chlorine admixture, etc., is equipped with various types of mechanical equipment such as measuring equipment, agitators, and sludge scrapers. The sludge sent to the sludge treatment facility is processed through, for example, a concentration tank, a digestion tank, a dehydrator, and an incinerator.

(sewage)
Traditionally, sewage has mainly consisted of domestic drainage, industrial drainage, and industrial drainage. In addition, plants such as branches and leaves, stems, grass, soil, etc. were sometimes mixed in the sewage. In recent years, there has been a tendency to incinerate the sludge generated by consolidating and treating septic tank drainage, agricultural wastewater, kitchen waste, diapers, etc. in the sewer to make energy by taking advantage of the scale of the sewage treatment plant. However, when these are introduced together with the sewage into the sewage treatment plant for intensive treatment, the amount of contaminants will also increase.

(Contaminants)
Contaminants contained in the sewage of sewage treatment facilities (eg, pump stations, storage pipes, sewage treatment plants, sludge treatment facilities, etc.) include plastics, underwear, rags, absorbent cotton and other fibers, waste cloth, toilet paper, and hair. Examples include, but are not limited to, raw garbage, oil balls, and diaper pieces.

Contaminants can be collected by screen equipment provided at pumping stations and sand basins, but generally the shape of contaminants (for example, size and length) varies, so the same equipment can be used for collection. There are some things that are not transparent. If the sewage containing contaminants flows into the sewage treatment plant, especially each treatment facility after the first settling tank, the equipments in each treatment facility will be entangled with the contaminants and malfunction of the equipments will occur. And, in some cases, hinder the operation of the entire sewage treatment plant. In addition, a heat exchanger may be provided to heat the sludge when reducing the volume of the sludge in the digestion tank.However, foreign matter may become entangled in the heat exchanger's pipes, etc., blocking the heat exchanger. It may also cause a malfunction.

In order to reduce such troubles and problems as much as possible, it is advisable to take measures to eliminate the adhesion and entanglement of foreign matters to the equipment and piping. For example, it is possible to take measures to reduce the size of foreign matters by crushing or cutting them. There are no particular limitations on the method for crushing or cutting the contaminants, and known means can be used, but it is preferable to provide a crushing device or a cutting device in the sewage treatment facility.

(Crushing device)
The structure of the crushing device is not limited, but a crushing device having a plurality of rotating shafts (for example, a biaxial shearing crusher or a multiaxial shearing crusher) can be used. The biaxial crushing device 20 will be described below as an example. An example of the biaxial shredding device is a device that has two rotating shafts that are arranged in parallel and that has shredding blades in the peripheral portion, and shreds foreign substances while sandwiching these rotating shafts to form the first foreign matter. .. The biaxial shredding device 20 has two substantially parallel first rotating shafts 24A and second rotating shafts 24B that rotate around the shaft center. The first rotary shaft 24A and the second rotary shaft 24B may be rotated by a gear motor or the like. It is preferable to use a configuration in which the first rotating shaft 24A is provided with a plurality of crushing disks 23A provided with a plurality of crushing blades 23a protruding outward in the radial direction in the axial direction. It is preferable that at least one crushing blade 23a is provided on the outer peripheral portion of the crushing disk 23A. The position of the crushing blades 23a of the crushing disk 23A group along the axial direction may be different in the axial direction around each crushing disk 23A, or may be arranged in a line. Similarly, the second rotating shaft 24B is also provided with a plurality of crushing disks 23B provided with a plurality of crushing blades 23b protruding outward in the radial direction in the axial direction. The crushing blade 23b has at least one crushing blade 23b, and the position of the crushing blade 23b of the crushing disk 23B along the axial direction may be different for each crushing disk 23B in the direction around the axial center, or in one row. You may line up in. The crushing discs 23A group and the crushing discs 23B group may be arranged at intervals along the axis, or may be arranged so that the adjacent crushing discs are in contact with each other without a gap. The plane direction of each of the crushing disk 23A and the crushing disk 23B is substantially perpendicular to the rotation axis direction. The first rotating shaft 24A having the crushing blades 23a and the second rotating shaft 24B having the crushing blades 23b may be arranged in the casing 25. When this structure is adopted, the sewage 10 is allowed to flow from the inflow portion 22 provided in the casing 25 into the crushing device 20 and the first treatment liquid 38 is allowed to flow out from the outflow portion 21. The group of crushing disks 23A provided on the first rotary shaft 24A and the group of crushing disks 23B provided on the second rotary shaft 24B may be separated by 7 to 10 mm. Further, both rotary shafts 24A, 24B may be arranged in a direction intersecting the inflow direction of the sewage 10.

The casing 25 does not necessarily have to be provided, and the biaxial shredding device 20 that does not include the casing 25 may be provided in a water channel or a pipe through which sewage flows. In addition, all of the sewage 10 may be sent to the same biaxial crushing device 20 or a part thereof, but it is preferable to send all.

When the sewage 10 is caused to flow into the crushing device, the impurities contained in the sewage 10 are crushed by the crushing blade. Then, the processing liquid 38 containing the crushed impurities (hereinafter, also referred to as “first processing liquid 38”) flows out from the crushing device. Of the contaminants, relatively small ones are appropriately crushed by the crushing device, or pass through without being crushed. Further, a relatively large contaminant may be crushed or compressed into a thickness that is the distance between the rotating shafts, and may have a thread-like or band-like form. The thread-shaped or strip-shaped morphology contained in the first treatment liquid 38 has, for example, a thickness of about 10 mm or less, but there are also those having a length of, for example, more than 50 cm. There is a risk of causing problems such as being attached to or entangled with equipment provided downstream of the treatment process. The impurities contained in the first treatment liquid 38 that has passed through the crushing device include the crushed first impurities and the impurities that have passed between the rotating shafts without being crushed.

(Cutting device)
As for the cutting device, the structure of the cutting device is not particularly limited as long as it can be crushed by a cutting blade, but the cutting device 30 according to the present embodiment can be preferably used for cutting foreign matters. .. Alternatively, the cutting device disclosed in Patent Document 2 or Patent Document 3 or the product “Rotacut” sold by Tsukishima Technomente Service Co., Ltd. may be used. The cutting device 30 shown in the present embodiment intersects the cutting blade 35 held by the holder 32 that rotates around the rotation axis of the flow direction 38b of the first processing liquid 38 and the flow direction 38b of the first processing liquid 38. And a counter plate 34 having a plurality of transmission holes 34a. The cutting blade 35 may have a form in which the cutting blade body is a blade, or may have a form in which the blade 35a is provided on the rotary blade 35b. The foreign matter is sandwiched between the cutting blade 35 and the facing plate 34, and is subjected to shearing force to be cut. Explaining with reference to FIG. 4, the cutting device 30 includes a cutting blade 35 (a rotary blade 35b and a blade edge 35a provided on the rotary blade) facing the surface of the facing plate 34. A plurality of transmission holes 34a penetrating the facing plate 34 are provided on the surface of the facing plate 34. The facing plate 34 may or may not include a blade. When the blade is provided, for example, the blade may be provided on the upstream side surface 34A of the first processing liquid 38 in the facing plate 34, or the edge of the transmission hole may be formed in a blade shape. The facing plate 34 may be in the form of a mesh, or may be a so-called mesh blade having the mesh itself as a cutting edge. Further, it may be a perforated plate, a sieve plate, or a lattice plate, and a form in which the edge of the perforation holes in the perforated plate, the sieve plate, or the lattice plate is formed by the cutting edge can be presented. Further, as shown in FIG. 6, it may be in the form of an opposed plate in which the transmission holes 34a having a substantially quadrangular shape or a substantially triangular shape are lined up while gradually expanding outward from the center in a spiral shape.

The cutting blade 35 may be installed upstream of the counter plate 34. The foreign matter is cut by the shearing force generated between the facing plate 34 and the cutting blade 35 when passing through the permeation hole 34a of the facing plate 34, but when it is arranged in this way, Of the impurities contained in the treatment liquid, the impurities retained (or caught) on the facing plate 34 are preferably cut by the rotating cutting blade 35.

The cutting blade 35 is provided on the rotatable holder 32, and when the holder 32 rotates, the cutting blade 35 rotates along the upstream flat surface 34A. The cutting blade 35a and the upstream flat surface 34A of the facing plate 34 rotate in a facing state of being close to or in contact with each other.

When the cutting blade 35 and the upstream flat surface 34A of the facing plate 34 are in contact with each other, the rotation of the cutting blade 35 causes the cutting blade 35 to scrape off the foreign matters adhering to the upstream flat surface 34A, and the foreign matters are surely removed. It is suitable for cutting. As an example of means for maintaining the state in which the cutting edge 35a of the cutting blade 35 is in contact with the upstream flat surface 34A, the holder 32 included in the cutting blade 35 is provided with a direction (biasing direction) 42 from the cutting blade 35 toward the facing plate 34. There can be mentioned a means 33a for urging. As a result, the cutting blade 35 can be rotated while being in contact with the upstream flat surface 34A of the facing plate 34 in the state of being pulled (biased) in the biasing direction 42. As the biasing means 33a, a known means such as a spring or a hydraulic cylinder can be used. The holder 32 may be rotated by a gear motor or the like.

The cutting blade 35 can be formed in a rotary blade shape. In this case, the number of blades can be set appropriately. For example, the number of sheets may be one, or two, three, four, five, eight, etc., and may be any number of 2 to 8.

The shape of the transmission holes 34a of the facing plate 34 is not particularly limited, but may be, for example, a substantially circular shape, a polygonal shape of a substantially triangular shape to a substantially hexagonal shape, a lattice shape, a mesh shape, or the like. The width (or diameter) of the transmission hole 34a can be set as appropriate, and is preferably set to 10 to 40 mm, for example, since contaminants are appropriately cut and penetrate the transmission hole 34a.

The cutting device 30 of the present embodiment is provided with an inflow part 36 into which the first treated water 38 flows and a outflow part 37 from which the water that has permeated the counter plate 34, that is, the second treated water 39 flows out. The facing plate 34 is provided so as to intersect the inflow direction 38a of the first treated water 38 at the inflow portion 36. The angle θ formed by the facing plate 34 (that is, the inclination 34r of the surface of the facing plate 34) and the inflow direction 38a of the first processing liquid 38 in the inflow portion 36 of the cutting device 30 may be a right angle, but as shown in FIG. It is preferable to make an acute angle. In particular, it is preferable that the angle θ when the angle is acute is 15° or more. When the angle is sharp, the impurities are easily caught by the facing plate 34 and remain there. Therefore, the amount of the impurities to be cut increases, and as a result, the second processing liquid containing a large amount of the short-cut impurities flows out from the cutting device 30. .. When the angle θ is smaller than 15°, the inflow direction 38a of the first processing liquid and the plane of the counter plate 34 become nearly parallel, and the speed at which the first processing liquid permeates the surface of the counter plate 34 becomes hydraulically small. The flow rate of the first treatment liquid passing through the facing plate 34 is reduced, and as a result, the treatment amount of sewage per unit time is reduced.

The facing plate 34 and the cutting blade 35 can be provided in the casing. The casing can be composed of two chambers, and the opposing plate 34 may be provided so as to partition the first chamber 40 and the second chamber 41. The first chamber is provided with the cutting blade 35 and the inflow portion 36, and the second chamber is provided with the outflow portion 37. In this case, the holder 32 provided on the cutting blade 35 may be extended to the second chamber side and may be arranged so as to extend to the biasing means 33a provided at the upper part of the second chamber. The first processing liquid 38 that has flowed into the first chamber passes through the counter plate 34, is guided to the second chamber, and flows out from the outflow portion 37 as the second processing liquid 39.

Further, a cutting device having a facing plate 34 and a cutting blade 35 may be provided in a water passage or a pipe in which the first treatment liquid 38 flows without providing the casing. In this case, needless to say, with respect to the flow direction of the first treatment liquid 38, the cutting blade 35 is arranged on the upstream side and the facing plate 34 is arranged on the downstream side so as to face each other.

All of the first processing liquid 38 may be transmitted to the counter plate 34, or a part thereof may be transmitted, but it is preferable that all of them be transmitted.

Contaminants contained in the first treatment liquid 38, particularly filamentous materials and belt-shaped materials, are subjected to a cutting force (shearing force) by the rotatable cutting blade 35 and/or the counter plate 34 to be cut. Therefore, most of the impurities contained in the second treatment liquid 39 have a thickness of 10 mm or less and a length of 50 mm or less, so that they are attached to or entangled with various equipment provided downstream of the present cutting device. Can be suppressed.

As another embodiment, the sewage 10 may be directly sent to the cutting device 30 without being sent to the crushing device 20. However, in this “other embodiment”, relatively large contaminants contained in the sewage remain on the facing plate 34 one after another, resulting in the blocking of the cutting device 30. Therefore, when only the cutting device 30 is provided without providing the crushing device 20, it is advisable to install the sewage treatment facility at a location where a relatively large amount of foreign substances is small. For example, it is preferable to install the cutting device 30 in the extraction sludge pipe of the first settling tank, the inflow pipe and the outflow pipe of the concentration tank and the digestion tank, respectively.

Another embodiment of the cutting device will be described with reference to FIG. 7. The cutting device 130 includes a cutting blade 135 (a blade 135a attached to the rotary blade 135b) on the side facing the facing plate 134. .. The opposed plate 134 is provided with a plurality of transmission holes penetrating the opposed plate 134. The cutting blade 135 is provided with a holder 132 that rotates by a gear motor 152 or the like, and the cutting blade 135 rotates along the surface of the facing plate 134 by the rotation of the holder 132. The cutting blade 135 is in contact with the upstream side surface of the first processing liquid 38 on the counter plate 134. Means 133 for urging the cutting blade 135 in the direction (biasing direction) from the cutting blade 135 toward the facing plate 134 for bringing the cutting blade 135 into contact with the facing plate 134 is provided. Further, impurities that cannot be completely cut and cannot pass through the counter plate 134 can be taken out from the take-out section 151 provided at the lower part of the cutting device 130. Further, when the operation of the main body is stopped, the upper part (above the counter plate 134) of the cutting device 130 can be opened counterclockwise with respect to the fulcrum shaft 100 provided in the main body 130 with respect to the paper surface. Then, the inside of the casing 136 can be visually recognized from above, and maintenance of the inside of the main body can be easily performed. When the cutting device 130 is operated with the upper part of the cutting device 130 closed, the first processing liquid 38 sent to the cutting device 130 passes through the facing plate 134, and as a result, the second processing liquid 39 is generated. can get.

Contaminants contained in the second treatment liquid 39 include, for example, first contaminants not crushed by the crushing device 20 and not crushed by the cutting device 30, secondly crushed by the crushing device 20, and The foreign matter not cut by the cutting device 30, the third foreign matter not crushed by the crushing device 20, and the foreign matter cut by the cutting device 30, the fourth crushing by the crushing device 20, and the cutting device 30 Includes contaminants cut in. The first treatment liquid 38 containing the first contaminants crushed by the crushing device 20 is caused to flow into the cutting device 30, and the first contaminants are cut into the second contaminants.

As described above, the thread-like or band-like contaminants adhere to the equipment of the sewage treatment facility or are entangled with each other. However, since the hair becomes coarse, it is preferable to cut it appropriately. When the hair exists in the sewage, organic matter, oils and fats, and other hair adhere to the cuticle portion on the surface of the hair. Moreover, when these are attached, bacteria propagate. Since the hair is formed of an enamel-like tissue, it has hardness, is hard to be biodegraded, and remains in the sewage treatment facility. Then, contaminants derived from hair become coarse, which may be a factor causing troubles in various facilities.

In the present embodiment, the sewage 10 flows into the crushing device 20 by the inflow means 51 and flows out as the first treatment liquid 38. Next, the first processing liquid 38 is supplied to the cutting device 30 by the water supply means 52, flows into the cutting device 30, and flows out as the second processing liquid 39 by the outflow means 53. The time required for the first treatment liquid 38 that has flowed out of the crushing device 20 to flow into the cutting device 30 may be within 60 seconds, and preferably 2 to 15 seconds. If it is longer than 60 seconds, the impurities crushed by the crushing device 20, especially the filamentous material and the band-like material, are deformed or agglomerated again into a large lump while reaching the cutting device 30, Crushing by the cutting device 30 becomes difficult. The water supply means 50 between the outflow part of the crushing device 20 and the inflow part 36 of the cutting device 30 is not particularly limited, and a pipe, a water channel, or the like can be used.

(Treatment of the second treatment liquid)
The contaminants contained in the second treatment liquid obtained in this embodiment may be removed so as not to be contained in the discharged water finally discharged from the sewage treatment facility. As a removing means, for example, a method can be adopted in which the contaminants are first extracted from the settling tank as sewage sludge, guided to a sludge storage tank, sent to a sludge treatment facility, and burned.

(Installation location)
The crushing device 20 and the cutting device 30 can be appropriately installed in a sewage treatment facility and a sludge treatment facility. For example, inlets and/or outlets of storage tanks of pumping stations and sludge aggregating equipment, inlets and outlets of sand basins/screen equipment, inlets of first sedimentation tanks, concentration tanks and digestion tanks, distribution tanks, scum storage It can be installed at the inlet and/or outlet of the tank. Moreover, it is good to install in at least any one of these installation places.

Although the cutting device 30 is installed on the downstream side of the location where the crushing device 20 is installed in the above description, the following embodiment may be adopted. An embodiment in which two crushing devices 20 are installed in series along the flow direction of the sewage 10 and a cutting device 30 is installed on the downstream side can be exemplified. Further, an embodiment in which two cutting devices 30 are installed in series on the downstream side of the location where the crushing device 20 is installed can also be exemplified. In this case, among the cutting devices 30 installed in series, the diameter of the permeation hole 34a of the counter plate 34 provided in the upstream first cutting device 30 is relatively increased so that the downstream second cutting device 30 has the same diameter. The diameter of the transmission hole 34a of the facing plate 34 provided may be relatively small. With this arrangement, the impurities are roughly cut by the first cutting device 30 and finely cut by the subsequent second cutting device 30, so that the impurities can be surely miniaturized.

(Flow rate)
The sewage 10 flowing into the crushing device 20 and the first treatment liquid 38 flowing into the cutting device 30 may have a flow rate of 10 to 100 m ³ /h and a total solid content (TS) of 0 to 4%. If the flow rate is less than 10 m ³ /h, the treatment efficiency will be poor, and if it exceeds 100 m ³ /h, a large amount of contaminants will flow into these devices, causing clogging. Further, if the total solid content (TS) exceeds 4%, the concentration of solids is too high, which causes clogging of these devices.

The sewage of the present embodiment is not particularly limited, but examples include septic tank drainage, agricultural/fishery village drainage, rainwater, factory drainage, workplace drainage, unknown water, underground water, spring water, groundwater, industrial water, sewer pipe water. , Sewer main water, raw sludge, activated sludge, process water flowing through each treatment process of a sewage treatment plant and/or a sludge treatment facility, and the like.

The sewage treatment method and the sewage treatment device disclosed in the present invention are not particularly limited, but can be used, for example, in public sewage, basin sewers, and sewage treatment facilities in urban sewers.

10 Sewage 20 2-axis crushing device 23a Crushing blade 23b Crushing blade 24A Rotating shaft 24B Rotating shaft 30 Cutting device 32 Holder 34 Counter plate 34A Upstream flat surface 34a of the first treatment liquid in the counter plate 35 Permeation hole 35 Cutting blade 38 First treatment liquid 39 Second treatment liquid

Claims (5)

A crushing step of causing sewage to flow into a biaxial crushing device, crushing impurities contained in the sewage into first impurities, and obtaining a first treatment liquid containing the first impurities;
A step of causing the first treatment liquid to flow into a cutting device, cutting the first contaminants to form second contaminants, and a second treatment liquid containing the second contaminants,
The biaxial crushing device is provided with two rotating shafts arranged in parallel with a crushing blade in the peripheral portion, and crushes while sandwiching the impurities with these rotating shafts, and the first crushing device having a thickness of 10 mm or less is used . It is a device that is a foreign matter,
The cutting device is
In the flow of the first processing liquid, a cutting blade held by a holder that rotates around a rotation axis of the flow direction of the first processing liquid, and a cutting blade that intersects the flow direction of the first processing liquid are provided. A counter plate having a plurality of permeation holes, and an inflow part for inflowing the first processing liquid,
The facing plate is provided such that an angle formed by the facing plate and an inflow direction of the first processing liquid in the inflow portion is an acute angle,
In the cutting step, the cutting blade is rotated in a facing state in which the cutting blade is close to or in contact with the facing plate to cut the first foreign substance to obtain the second foreign substance having a length of 50 mm or less , Permeating through the permeation hole to obtain the second processing liquid,
A sewage treatment method characterized by the above. There is a step of feeding the first treatment liquid obtained in the crushing step from an outflow section of the crushing apparatus to an inflow section of the cutting apparatus through a pipe having a substantially constant diameter.
The sewage treatment method according to claim 1. A step of causing the second treated liquid to flow into a first settling tank and drawing it out as sewage sludge from the first settling tank;
The sewage treatment method according to claim 1. The time for the first processing liquid flowing out of the biaxial crushing device to reach the cutting device is within 60 seconds,
The sewage treatment method according to claim 1. A sewage treatment device for crushing and cutting impurities contained in inflowing sewage,
The sewage treatment device,
A biaxial crushing device for crushing impurities to obtain first impurities and obtaining a first treatment liquid containing the first impurities;
A cutting device for cutting the first contaminant to obtain a second contaminant and obtaining a second treatment liquid containing the second contaminant,
The biaxial crushing device is provided with two rotating shafts arranged in parallel with a crushing blade in the peripheral portion, and crushes while sandwiching the impurities with these rotating shafts, and the first crushing device having a thickness of 10 mm or less is used . It is a foreign matter,
The cutting device is
In the flow of the first processing liquid, a cutting blade held by a holder that rotates around a rotation axis of the flow direction of the first processing liquid, and a cutting blade that intersects the flow direction of the first processing liquid are provided. A counter plate having a plurality of permeation holes and an inflow part for inflowing the first processing liquid,
The facing plate is provided so that an angle formed by the facing plate and an inflow direction of the first processing liquid in the inflow portion is an acute angle, and the cutting blade is rotated in a facing state in which the cutting blade is close to or in contact with the facing plate. Then, the first contaminant is cut into the second contaminant.
A sewage treatment device characterized by the above.

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