JP4860306B2 - Sewage purification system - Google Patents

Description

  The present invention relates to a sewage purification system for purifying sewage discharged from, for example, a food processing factory.

  In general, wastewater containing organic substances such as lipids, carbohydrates, and proteins that are no longer needed and discarded when food is processed, for example, in food processing factories is discharged. Is used to remove and reduce BOD (Biochemical Oxygen Demand), SS (Suspended Solid), n-Hex (n-Hexane Extracted Substance), etc. Yes.

  Conventionally, as this kind of sewage purification system, there is one related to the research of the inventors of the present application, for example, one described in Patent Document 1 (Japanese Patent Laid-Open No. 2005-66446) is known. .

As shown in FIG. 10, this purification system Sa includes an adjustment tank 2 into which sewage discharged from a food processing factory 1 or the like flows, an aeration tank 3 provided at the rear of the adjustment tank 2, and an aeration tank 3. A sedimentation tank 4 provided at the rear is provided, and sewage is allowed to flow from the adjustment tank 2 to the sedimentation tank 4 to purify the sewage in this process.
The aeration tank 3 is provided with a blower B, and blows air with the blower B to decompose organic substances such as suspended solids in wastewater by microorganisms such as resident bacteria.
Moreover, the sewage processed in the aeration tank 3 is stored in the settling tank 4, and suspended substances in the sewage are collected and settled and taken out as sludge.

  Further, the purification system Sa is provided with a magnetic field applying device 6 that applies a magnetic field to the sewage in the adjustment tank 2. The magnetic field applying device 6 is provided outside the adjustment tank 2, a pump 9 that pumps up the sewage in the adjustment tank 2, a passage pipe 7 that passes the sewage pumped up by the pump 9 and returns it to the adjustment tank 2 again. And a magnet (not shown) for applying a magnetic field to the sewage. In the figure, 8 is a scattering mechanism which is provided at the outlet of the passage pipe 7 located at a position higher than the surface of the sewage in the adjustment tank 2 and scatters the sewage flowing out from this outlet.

In order to purify the sewage using the sewage purification system Sa, the sewage is poured into the adjustment tank 2, the aeration tank 3, and the settling tank 4 in order from the adjustment tank 2.
In the adjustment tank 2, since the magnetic field is applied to the sewage by the magnetic field applying device 6, when a suspended substance made of organic matter or the like in the sewage passes through the magnetic field, it is refined by the magnetic field.
In addition, air is blown into the sewage flowing into the aeration tank 3 from the adjustment tank 2, so that organic substances in the sewage are decomposed by aerobic bacteria or oxidized by oxygen in the air, and BOD and SS is reduced and eliminated. Then, floating substances composed of organic matter, microorganisms, etc. that remain without being decomposed in the sewage in the sedimentation tank 4 are collected and precipitated, and the supernatant of the sedimentation tank 4 is discharged into the river 5 or the like.
Sludge formed by collecting suspended substances precipitated in the settling tank 4 is taken out, dehydrated by a dehydrator (not shown), and discarded.

JP 2005-66446 A

  By the way, in such a sewage purification system Sa, the sewage in the adjustment tank 2 does not have enough microorganisms with respect to the amount of organic matter in the sewage, and the organic matter in the sewage is not easily taken up by the microorganisms. Then, even if it is sent to the aeration tank 3 and air is blown in, it takes time until the organic matter is sufficiently decomposed. Further, since the purification efficiency of sewage is inferior, there is a problem that the amount of sludge discharged is relatively large and the sludge treatment cost is increased. There is also a problem that the organic substance is not sufficiently refined by the magnetic field applying device 6.

  The present invention has been made in view of the above problems, and in a tank preceding the aeration tank, the organic matter is sufficiently refined so that the microorganism can easily take in the organic matter, and the amount of the organic matter is sufficient. To provide a sewage purification system that improves the efficiency of sewage purification and reduces sludge discharge by allowing microorganisms to efficiently decompose organic matter in the aeration tank. Objective.

The sewage purification system of the present invention for achieving such an object includes an adjustment tank into which sewage flows, and an aeration tank that is provided on the rear side of the adjustment tank and performs microbial treatment on the sewage from the adjustment tank side. And a sewage purification system comprising at least three tanks, which are provided on the rear side of the aeration tank and precipitate the sewage treated with microorganisms in the aeration tank, on the front side of the aeration tank. A circulation path for circulating sewage in a certain tank is provided, a magnetic field applying device for applying a magnetic field to the sewage flowing through the circulation path is provided, and sludge precipitated in the settling tank is returned to the tank provided with the circulation path. Based on the configuration with sludge return path ,
Between the adjustment tank and the aeration tank, a sludge charging tank for mixing the sludge from the adjustment tank and the sludge returned from the sedimentation tank by the sludge return path is provided.
The circulation path comprises a supply path for feeding the sewage in the adjustment tank to the sludge input tank, and a sewage return path for returning the sludge in the sludge input tank to the adjustment tank,
It is set as the structure which provided the said magnetic field provision apparatus in the sewage return path | route of the said circulation path.
Another sewage purification system of the present invention is provided with a sewage agitation tank for agitating sewage in front of the adjustment tank, and returned from the sewage agitation tank and the settling tank through the sludge return path. A primary sludge charging tank that mixes with the sludge and feeds it to the adjustment tank,
Between the adjustment tank and the aeration tank, a secondary sludge charging tank that mixes the sludge from the adjustment tank and the sludge returned from the sedimentation tank by the sludge return path is provided.
The circulation path is configured with a primary circulation path and a secondary circulation path,
The primary circulation path includes a supply path for feeding the sewage in the sewage agitation tank to the primary sludge input tank, and a first sewage return path for returning the sewage in the primary sludge input tank to the sewage agitation tank. And configure
The secondary circulation path includes a supply path for feeding the sewage from the adjustment tank to the secondary sludge input tank, and a second sewage return path for returning the sewage from the secondary sludge input tank to the adjustment tank. Configure and prepare
The first magnetic sewage return path of the primary circulation path and the second sewage return path of the secondary circulation path are each provided with the magnetic field applying device.

  When the sewage purification system is used, it flows into the adjustment tank which is the tank on the front side of the aeration tank. Moreover, sludge is returned to the tank provided with the circulation path by the sludge return path. Then, the sewage is circulated together with the sludge through the circulation path, and the sewage and the sludge are mixed in the circulation process.

When the sewage passes through the circulation path, a magnetic field is applied by the magnetic field applying device, and the suspended matter and sludge, which are organic substances, are refined. Thereby, suspended solids and sludge are uniformly dispersed in the sewage.
In addition, the suspended matter in the sewage is mainly negatively charged, and the sludge is mainly positively charged, so the suspended matter and the sludge in the sewage are naturally adsorbed. Therefore, the sludge returned to the tank provided with the circulation path can be attached to the surface of the suspended matter.

  At this time, by returning the sludge, the number of microorganisms attached to the unit amount of the suspended matter which is an organic substance increases, and a sufficient number of microorganisms can be attached to the suspended matter. In addition, since the suspended solids are refined and the surface area of the suspended solids in the sewage is increased, the sludge is well adsorbed on the surface of the suspended solids. The suspended solids adsorbed by the sludge are predated by the relatively large microorganisms in the sludge and decomposed to become organic substances having a small molecular weight. At this time, since it is miniaturized, it is possible to easily prey on floating substances that are organic substances not dissolved in sewage such as protists.

  In addition, in the circulation path, sewage and sludge are mixed well, and not only the suspended matter is refined by magnetic fields and microorganisms, but the suspended matter is also refined by the action of enzymes synthesized by microorganisms. . In this way, if the suspended matter, which is an organic substance, is further refined by applying a magnetic field or being decomposed by an enzyme / microorganism, the suspended matter is changed from a polymer to a low molecule and easily dissolved in sewage. . Organic matter dissolved in sewage is taken up by microorganisms.

  When the sewage and the sludge are sufficiently mixed in the circulation path and the suspended matter in the sewage is sufficiently refined, the sewage is fed to the aeration tank side. At this time, the sewage is circulated through the circulation path, and the sewage and the sludge are sufficiently mixed, so that the organic matter is sufficiently refined.

When sewage is fed from the tank in front of the aeration tank to the aeration tank, and air is blown into the aeration tank, most of the suspended substances that are organic matter are dissolved as low-molecular organic substances and taken up by microorganisms. Therefore, microorganisms grow by cell division or the like using air in the aeration tank and taking in the organic matter taken up, and most of the organic matter becomes carbon dioxide and water during the growth process.
That is, in the past, most floating substances were decomposed by microorganisms present in the aeration tank in the aeration tank. On the other hand, in the present invention, before flowing into the aeration tank, the floating substance that is an organic substance in advance is used. Since most of them are sufficiently refined and dissolved in sewage, they are sized to take in microorganisms, and a sufficient number of microorganisms are added to the amount of suspended matter in the sewage. When it flows into the aeration tank, it is quickly decomposed by oxygen in the air blown into the aeration tank. Therefore, microorganisms can efficiently decompose organic substances, and BOD and SS in wastewater can be quickly removed and reduced, and the purification efficiency of wastewater can be improved. In addition, since the purification processing efficiency is high, the processing time can be shortened. In addition, since the purification processing efficiency is high, the processing time can be shortened.
In addition, suspended solids that could not be refined in the tank preceding the aeration tank are decomposed and refined using oxygen in the air blown by the blower, and then carbon dioxide and water in the same manner as described above. And decomposed.
Then, the sewage is fed from the aeration tank to the settling tank in a timely manner.

In the settling tank, floating substances and microorganisms that cannot be completely decomposed in the aeration tank are collected to form a so-called floc, and the floc is precipitated, while the supernatant is discharged into a river or the like.
At this time, microorganisms can efficiently decompose organic substances in the aeration tank, and the purification efficiency of the sewage is improved, so that the amount of sludge that precipitates is small.
In addition, suspended solids and microorganisms precipitated in the settling tank are sent as sludge to a tank provided with a circulation path via a sludge return path. As a result, the sludge settled in the settling tank is sent to the tank provided with the circulation path through the sludge return path, and is used for adding microorganisms to the tank preceding the aeration tank, and the sludge itself Will flow into the aeration tank again. As a result, suspended solids that could not be decomposed in the aeration tank are decomposed again, so most of what is discarded in the precipitation tank is discarded only by microorganisms such as inorganic substances, and discarded. The amount of sludge produced is very low.

Next, the sewage purification system proposed in the development stage of the present invention will be shown for reference. This system includes an adjustment tank into which sewage flows, an aeration tank provided on the rear side of the adjustment tank for performing microbial treatment on the sewage from the adjustment tank side, and an aeration tank provided on the rear side of the aeration tank. In a sewage purification system having at least three tanks, including a sedimentation tank for precipitating microbially treated sewage in the tank, the sewage in the tank on the front side of the aeration tank is fed to the tank on the rear side. Provide a magnetic field applying device that applies a magnetic field to the sewage flowing through the feed path, and return the sludge that has settled in the settling tank to the tank on the front side of the feed path provided with the magnetic field applying device. It is set as the structure which provided the path.

  If this sewage purification system is used, it will flow into the adjustment tank which is the tank of the front side of an aeration tank. On the other hand, the sludge is returned to the tank on the front side of the supply route provided with the magnetic field applying device by the sludge return route.

When the sewage passes through the supply path and a magnetic field is applied by the magnetic field applying device, suspended matter and sludge that are organic substances are refined. Therefore, suspended substances and sludge are easily dispersed in the sewage.
And in the tank in front of the aeration tank, the suspended solids in the sewage are mainly negatively charged and the sludge is mainly positively charged. Adsorb.

  At this time, by returning sludge to the tank on the front side of the supply path provided with the magnetic field application device, the number of microorganisms per unit amount of suspended solids increases, which is sufficient for suspended solids. A number of microorganisms can be attached. In addition, since the suspended matter is refined by the magnetic field applying device, the entire surface area of the suspended matter in the sewage is increased, and the sludge is well adsorbed on the surface of the suspended matter. The suspended solids adsorbed by the sludge are predated by the relatively large microorganisms in the sludge and decomposed to become organic substances having a small molecular weight. At this time, since the suspended matter is refined, predation of the suspended matter, which is an organic substance not dissolved in sewage such as protists, can be easily performed, and the refinement can be promoted.

In addition to the refinement of suspended solids due to a magnetic field, organic substances and organic substances are also affected by the action of enzymes synthesized by microorganisms in the sludge returned to the tank on the front side of the supply path provided with the magnetic field application device. Some suspended matter is refined.
In this way, when the suspended matter is further refined due to the application of a magnetic field, decomposition by microorganisms, and the action of oxygen, the suspended matter, which is an organic substance, changes from a high molecular to a low molecular, and dissolves in sewage. It becomes easy. Organic matter dissolved in sewage is taken up by microorganisms.

When the sewage is fed from the tank in front of the aeration tank to the aeration tank, and air is blown into the aeration tank, most of the suspended substances that are organic matter are dissolved as low-molecular organic substances, and microorganisms Therefore, microorganisms grow by cell division or the like, using air in the aeration tank as a nutrient and using the taken-in organic matter as nutrients, and most of the organic matter becomes carbon dioxide and water during the growth process.
That is, in the past, most floating substances were decomposed by microorganisms present in the aeration tank in the aeration tank. On the other hand, in the present invention, before flowing into the aeration tank, the floating substance that is an organic substance in advance is used. Since most of them are sufficiently refined and dissolved in sewage, they are sized to take in microorganisms, and a sufficient number of microorganisms are added to the amount of suspended matter in the sewage. When it flows into the aeration tank, it is quickly decomposed by oxygen in the air blown into the aeration tank. As a result, microorganisms can efficiently decompose organic substances, and BOD and SS in wastewater can be quickly removed and reduced, thereby improving the purification efficiency of wastewater. In addition, since the purification processing efficiency is high, the processing time can be shortened.
In addition, since the purification processing efficiency is high, the processing time can be shortened.
Further, the suspended solids remaining in the tank preceding the aeration tank that cannot be refined are decomposed and refined using oxygen in the air blown by the blower, and then, as described above, carbon dioxide and water. And decomposed.
Then, the sewage is fed from the aeration tank to the settling tank in a timely manner.

In the settling tank, floating substances and microorganisms that cannot be completely decomposed in the aeration tank are collected to form a so-called floc, and the floc is precipitated, while the supernatant is discharged into a river or the like.
At this time, in the aeration tank, microorganisms can efficiently decompose organic substances and the purification efficiency of sewage is improved, so that the amount of sludge that precipitates is reduced.
Moreover, the suspended solids and microorganisms that have settled in the settling tank are sent as sludge to a tank preceding the feed path provided with the magnetic field applying device via the sludge return path. As a result, the sludge that has settled in the settling tank is used for adding microorganisms to the tank preceding the aeration tank by sending it to the tank preceding the feed path provided with the magnetic field applying device. The sludge itself will flow again into the aeration tank. As a result, suspended solids that could not be decomposed in the aeration tank are decomposed again, so most of what is discarded in the precipitation tank is discarded only by microorganisms such as inorganic substances, and discarded. The amount of sludge produced is very low.

In addition, if necessary, the magnetic field applying device is provided with a through-tube through which sewage passes, a magnetic field generating unit including a plurality of electromagnets provided on one circumference outside the through-tube, and a current flowing through the electromagnet. And a power source for supplying the air.
Thereby, the organic matter and sludge pass through the magnetic field formed in the pipe along with the sewage, and the organic matter and sludge are refined by stimulation of the magnetic field.
In addition, since a plurality of electromagnets are provided on one circumference outside the pipe, it is possible to uniformly apply a magnetic field over the entire circumference around the axis of the pipe to the sewage passing through the magnetic field generation unit. Organic matter and sludge can be refined efficiently.

Furthermore, as necessary, the magnetic field generator is configured by providing a plurality of pairs of electromagnets that are provided symmetrically about the axis of the tube and that have different polarities.
As a result, a plurality of electromagnets of the magnetic field generating section are crossed over the magnetic field, and miniaturization can be performed efficiently.

Furthermore, pulse voltage generation means is provided for applying a pulsed voltage to the pair of electromagnets to form a pulsed magnetic field by the pair of electromagnets as necessary.
Thereby, since the pulse magnetic field is formed, compared with the case where the magnetic field is simply applied, the stimulation to the organic matter and the sludge becomes stronger, and the organic matter and the sludge can be further refined more efficiently. Moreover, the activity of the enzyme synthesized by the microorganism can be promoted, and the organic substance can be efficiently refined by the activated enzyme.

Further, if necessary, sequential excitation means for sequentially exciting the respective electromagnet sets is provided.
Thereby, the direction of the magnetic field can be applied to the organic matter and sludge in the sewage in a complicated manner, the stimulation to the organic matter and sludge becomes stronger, and further refinement of the organic matter and sludge can be performed more efficiently. .

Furthermore, if necessary, a plurality of the magnetic field generators are arranged in the axial direction of the pipe.
Since there are a plurality of magnetic field generators, the organic matter and sludge can be efficiently refined as compared with the case of one magnetic field generator.

According to the sewage purification system of the present invention, a magnetic field applying device for applying a magnetic field to the sewage flowing through the circulation path is provided, and a sludge return path for returning sludge settled in the settling tank is provided in a tank provided with the circulation path. In addition, the suspended matter and sludge, which are organic substances, are made finer before entering the aeration tank by the magnetic field by the magnetic field applying device and the microorganisms in the sludge returned by the sludge return path, and the sludge Due to the sludge returned by the return path, the number of microorganisms is sufficient for the amount of organic matter in the entire sewage. Therefore, when it flows into the aeration tank and air is blown into the aeration tank, the organic matter is quickly decomposed by oxygen in the air. Thereby, removal and reduction of BOD, SS, etc. in sewage are performed rapidly, and the purification processing efficiency of sewage can be improved. In addition, since the purification processing efficiency is high, the processing time can be shortened. Moreover, since sewage and sludge are sufficiently mixed in the circulation path, refinement of organic substances can be promoted.
Furthermore, the amount of the sludge precipitated in the settling tank can be reduced because the purification treatment efficiency of the sewage in the aeration tank is improved. Furthermore, since it is used for adding microorganisms to the tank provided with the circulation path, the sludge itself flows again into the aeration tank. As a result, suspended solids that could not be decomposed in the aeration tank are decomposed again, so most of what is discarded in the precipitation tank is discarded only by microorganisms such as inorganic substances, and discarded. The amount of sludge produced can be greatly reduced.

  Hereinafter, a sewage purification system according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a sewage purification system S1 according to the first embodiment of the present invention.
The sewage purification system S1 purifies, for example, wastewater discharged from the food processing factory 1 as sewage. This sewage mainly contains organic substances such as lipids, carbohydrates, and proteins dissolved in the sewage, or a collection of organic substances that do not dissolve as floating substances. Cause of SS.
In this sewage purification system S1, the organic matter is decomposed by microorganisms to remove and reduce BOD and SS. Microorganisms are composed of protists and resident bacteria such as flagellates, ciliates and rhizopods.

  Specifically, the sewage purification system S1 includes an adjustment tank 10 into which sewage flows, an aeration tank 20 that is provided on the rear side of the adjustment tank 10 and performs microbial treatment on the sewage from the adjustment tank 10, and an aeration tank 20 from a settling tank 30 that is disposed on the rear side of the tank 20 and precipitates sewage treated with microorganisms in the aeration tank 20, and the sludge W that has settled in the settling tank 30 between the adjustment tank 10 and the aeration tank 20 and the adjustment tank 10. And a sludge charging tank 40 for mixing the infused sludge W. In the sewage purification system S1, sewage is disposed between the adjustment tank 10 and the sludge charging tank 40, between the sludge charging tank 40 and the aeration tank 20, and between the aeration tank 20 and the precipitation tank 30. Feeding paths 11, 21, 41 for feeding to the tank on the side are provided, and sewage can be flowed sequentially from the adjustment tank 10 toward the tank on the rear side.

Waste water from the food processing plant 1 flows into the adjustment tank 10 as sewage.
Further, in the adjustment tank 10, a suction pump 12 that pumps up the sewage in the adjustment tank 10 is provided in a feeding path 11 provided between the adjustment tank 10 and the sludge charging tank 40.

  The aeration tank 20 is provided with a blower 22 that blows air into the sewage in the aeration tank 20. In the aeration tank 20, by blowing air with the blower 22, in particular, aerobic bacteria and the like are activated and the suspended matter is decomposed. The sewage supply path 21 between the aeration tank 20 and the settling tank 30 causes the sewage to overflow from the aeration tank 20 and flow into the settling tank 30.

The sedimentation tank 30 collects suspended substances in the sewage flowing in from the aeration tank 20, precipitates the so-called floc with a specific gravity greater than that of the sewage, and takes it out as sludge W. This precipitated sludge W contains protists such as flagellates, ciliates and rhizobia, and microorganisms such as resident bacteria. In addition, sludge contains many enzymes that are synthesized by these microorganisms and decompose the organic matter from high molecular weight to low molecular weight so that the microorganism itself can easily take up organic matter as nutrients for carrying out life activities. include.
Further, from the sedimentation tank 30, the supernatant is discharged into, for example, the river 5 or the like.

The sludge input tank 40 is provided with a suction pump 42 that pumps up the sludge in the sludge input tank 40 to a feed path 41 provided between the sludge input tank 40 and the aeration tank 20.
Further, the sludge input tank 40 is provided with a sludge return path 45 for returning the sludge W precipitated in the settling tank 30. For example, a pump (not shown) is interposed in the sludge return path 45, and the sludge W at the bottom of the sedimentation tank 30 is sucked by the suction of the pump and the sludge W is sent to the sludge charging tank 40 side. Yes.

Furthermore, the adjustment tank 10 and the sludge charging tank 40 are provided with a circulation path 50 for circulating the sewage in the adjusting tank 10 and the sludge charging tank 40. The circulation path 50 includes a feeding path 11 provided between the sludge charging tank 40 and the adjusting tank 10 and a sewage returning path 51 for returning the sewage from the sludge charging tank 40 to the adjusting tank 10.
The sewage return path 51 has an inlet of sewage and an outlet on the adjustment tank 10 side at the bottom of the sludge charging tank 40, and the outlet is positioned higher than the surface of the sewage stored in the adjustment tank 10. . Further, sewage flows into the sewage return path 51 by a pump 52 provided at the bottom of the sludge charging tank 40 from its inlet. Furthermore, the outlet of the circulation path 50 is provided with a scattering mechanism 53 that scatters sewage that flows out of the outlet and falls into the adjustment tank 10.

Further, as shown in FIGS. 1 to 5, the circulation path 50 is provided with a magnetic field applying device 60 that applies a magnetic field to sewage flowing through the circulation path 50. Specifically, the magnetic field applying device 60 includes a passage 61 through which sewage passes and a plurality of electromagnets 62a, 62b, 62c, 62d, 62e, and 62f that are provided on one circumference outside the passage 61 and generate a magnetic field. A magnetic field generator 62 and a power source 64 for supplying current to the electromagnets 62a, 62b, 62c, 62d, 62e, and 62f are provided.
The through pipe 61 constitutes a part of the sewage return path 51.
The magnetic field generator 62 is a pair of electromagnets that are provided symmetrically about the axis of the pipe 61 and have different polarities (first electromagnet sets 62a and 62b, second electromagnet sets 62c and 62d, A plurality of sets of three electromagnets 62e, 62f) are provided. In addition, the electromagnets 62a, 62b, 62c, 62d, 62e, and 62f of the magnetic field generator 62 are attached to a substrate 63 in which wirings to the electromagnets 62a, 62b, 62c, 62d, 62e, and 62f are formed. . In the embodiment, three pairs of magnets are provided in a substantially equiangular relationship. Further, as shown in FIG. 5, the magnetic field generators 62 are arranged in a plurality of rows in the axial direction of the tube.

  Furthermore, as shown in FIGS. 2 and 5, in each magnetic field generator 62, a first electromagnet set 62a, 62b, a second electromagnet set 62c, 62d, and a third electromagnet set 62e, 62f, respectively. Pulse voltage generating means 65 for applying a pulse voltage to the first electromagnet set 62a, 62b, the second electromagnet set 62c, 62d, and the third electromagnet set 62e, 62f to form a pulsed magnetic field; In each magnetic field generator 62, a first electromagnet set 62a and 62b, a second electromagnet set 62c and 62d, and a third electromagnet set 62e and 62f are sequentially excited and sequentially excited means 66 is provided. Yes.

The pulse voltage generation means 65 includes a transmission circuit 67 that generates a pulse voltage with a constant period and a shift register. Further, the sequential excitation means 66 is composed of a shift register.
The shift register which is the sequential excitation means 66 is operated by the pulse voltage of the transmission circuit 67 and applies a voltage to each set of electromagnets in order for each cycle of the transmission circuit 67. According to the sequential excitation means 66, for example, as shown in FIG. 7, the first set of electromagnets 62a and 62b, the second set of electromagnets 62c and 62d, and the third set of electromagnets 62e and 62f. The pulse voltage is sequentially applied (ON), and the application is canceled (OFF) to excite each electromagnet set. The pulse voltage generated by the transmission circuit 67 is, for example, λ = 5 to 25 μm where the wavelength λ of the pulse voltage applied to each electromagnet 62a, 62b, 62c, 62d, 62e, 62f is equal to the so-called growth light wavelength λ. The frequency is set to be in the range.
In the figure, reference numeral 68 denotes an amplifier circuit that amplifies the pulse voltage to an appropriate voltage.

When this purification system S1 is used to purify sewage, the following occurs.
As shown in FIG. 1, sewage from the food processing plant 1 flows into the adjustment tank 10, and the sewage is pumped by the pump 12 in the adjustment tank 10 and fed to the sludge charging tank 40 through the feed path 11. Is done. At this time, as shown in FIG. 7 (a), the sewage from the food processing plant 1 has dissolved organic substances and suspended substances that are aggregates of undissolved organic substances, and the amount of suspended substances is considerably increased. Yes.
In addition, the sludge W is introduced into the sludge introduction tank 40 through the sludge return path 45. And it is made to circulate with the sewage between the adjustment tank 10 and the sludge input tank 40 by the circulation path 50, and the sludge W is mixed with sewage in the circulation process (FIG.7 (b)). At this time, the organic matter and sludge W circulating in the circulation path 50 are electrically charged with the suspended matter in the sewage being mainly negative, and the sludge W is mainly electrically charged positively. And will naturally adsorb. Thereby, the sludge W is thrown into the sludge throwing tank 40, and the sludge W can be attached to the surface of a floating substance (FIG.7 (c)).

In the circulation path 50, when the sewage passes through the pipe 61 that is a part of the sewage return path 51, a magnetic field is applied by the magnetic field applying device 60.
As shown in FIGS. 7 (d) and 7 (e), in the pipe 61, organic matter and sludge W in the sewage are separated from the plurality of electromagnets 62a, 62b, 62c, 62d, 62e, 62f flows through the pipe 61 across the magnetic field excited. Therefore, organic matter and sludge W are stimulated by a magnetic field and are refined.
At this time, since a plurality of electromagnets 62 a, 62 b, 62 c, 62 d, 62 e, and 62 f are provided on one circumference on the outside of the pipe 61, the sewage that passes through the magnetic field generator 62 is placed around the axis of the pipe 61. Thus, the magnetic field can be applied uniformly over the entire circumference, and the organic matter and the sludge W can be refined efficiently.

The pulse voltage generation means 65 forms a pulse magnetic field with a pair of electromagnets (first electromagnet set 62a, 62b, second electromagnet set 62c, 62d, and third electromagnet set 62e, 62f). Therefore, compared with the case where the magnetic field is simply applied, the stimulation to the organic matter and the sludge W becomes stronger, and the organic matter and the sludge W can be further miniaturized more efficiently.
Moreover, the microorganisms in the sludge W can be activated by giving the pulse magnetic field of a wavelength substantially equivalent to a growth light beam. In particular, the activity of enzymes in sewage can be promoted.
Further, since the first electromagnet set 62a and 62b, the second electromagnet set 62c and 62d, and the third electromagnet set 62e and 62f are sequentially excited, the sequential excitation means 66 is provided. The direction of the magnetic field can be imparted to W differently, the stimulation to the organic matter and the sludge W becomes stronger, and the organic matter and the sludge W can be further refined more efficiently.

  In addition, since the sludge W is returned through the sludge return path 45, the number of microorganisms attached to the unit amount of the suspended matter is increased, and a sufficient number of microorganisms can be attached to the suspended matter. Moreover, since the suspended solids are refined and the entire surface area of the suspended solids in the sewage is increased, the sludge W is well adsorbed on the surface of the suspended solids. The suspended matter adsorbed by the sludge W is mainly preyed by protists and the like, which are relatively large microorganisms in the sludge W, and decomposed to become organic substances having a small molecular weight. At this time, since the organic matter is refined, predation of protists can be easily performed.

Further, in the circulation path 50, sewage and sludge W are mixed well, and the organic matter is refined not only by the refinement of the organic matter by magnetic field and microorganism supplementation but also by the action of the enzyme synthesized by the microorganisms and the like. .
Further, when the sewage falls into the adjustment tank 10 at the outlet of the sewage return path 51, the sewage is scattered by the scattering mechanism 53, so that the suspended matter in the sewage scattered and oxygen in the atmosphere are easily combined. Therefore, before reaching the aeration tank 20, microorganisms in the sewage use oxygen in the atmosphere in the adjustment tank 10, or oxygen is bound to the suspended matter itself to oxidize and decompose the suspended matter to some extent. be able to.
As described above, in the circulation path 50, when the fineness of the suspended matter further proceeds, the organic matter of the suspended matter is changed from a polymer to a low molecule, and is easily dissolved in sewage (FIG. 7 (e)). Organic matter dissolved in sewage is taken up by microorganisms.

When the sludge and the sludge W are sufficiently mixed in the sludge charging tank 40, the adjustment tank 10 and the circulation path 50 and the suspended matter in the sludge is sufficiently refined, the pump 42 of the sludge charging tank 40 is turned on. The sewage is supplied to the aeration tank 20 through the supply path 41.
When sewage is fed to the aeration tank 20 and air is blown into the aeration tank 20 by the blower 22, most of the organic matter is dissolved in low molecular weight and is taken up by microorganisms. Relatively small microorganisms such as aerobic bacteria use the air from the blower 22 and grow by cell division etc. using the taken-in organic matter as nutrients, and in the growth process, most of the organic matter becomes carbon dioxide and water. .

That is, conventionally, the aeration tank 20 decomposes floating substances, which are microorganisms present in the aeration tank 20 and are organic substances. In contrast, in the present invention, before flowing into the aeration tank 20, floating is performed in advance. By refining the substance, most of the organic matter is sufficiently dissolved in the sewage water so that the organic matter can be easily taken in by the microorganisms, and the sludge W is introduced into the sludge input tank 40 through the sludge return path 45 and the organic matter in the sewage. Since a sufficient number of microorganisms are added to the amount of the gas, when it flows into the aeration tank 20, it is quickly decomposed by oxygen in the air blown into the aeration tank 20 by the blower 22. Thereby, removal and reduction of BOD, SS, etc. in sewage are performed rapidly, and the purification processing efficiency of sewage is improved. In addition, since the purification processing efficiency is high, the processing time can be shortened.
Further, the suspended matter that cannot be completely refined is decomposed and refined using oxygen in the air blown by the blower 22, and then decomposed into carbon dioxide and water in the same manner as described above. Then, the sewage is fed from the aeration tank 20 to the sedimentation tank 30 by the overflow through the feeding path 21 at an appropriate time.

  In the sedimentation tank 30, floating substances and microorganisms that could not be decomposed in the aeration tank 20 are collected to form a so-called floc, and the floc is precipitated, while the supernatant is discharged into the river 5 or the like. The suspended matter and microorganisms that have settled in the sedimentation tank 30 are sent to the sludge input tank 40 through the sludge return path 45 as sludge W. As a result, the sludge W that has settled in the settling tank 30 is sent to the tank in front of the aeration tank 20 via the sludge return path 45 so that microorganisms are added to the tank in front of the aeration tank 20. In addition, the sludge W itself flows into the aeration tank 20 again. Therefore, since the suspended solids and the like that cannot be decomposed in the aeration tank 20 are decomposed again, most of what is deposited in the precipitation tank 30 is discarded only by microorganisms such as inorganic substances that cannot be decomposed. Therefore, the amount of sludge W to be discarded becomes very small.

Next, a sewage purification system according to a second embodiment of the present invention will be described.
As shown in FIG. 8, this sewage purification system S2 is used for sewage containing a large amount of suspended solids and having a high BOD, SS value. Specifically, the sewage purification system S2 is different from the sewage purification system S1 of the first embodiment, and a sewage agitation tank 70 that sewage from the food processing factory 1 flows into and agitates the sewage inside. A primary sludge charging tank 80 provided at the rear of the sludge agitation tank 70 in which the sludge W and the sludge from the sludge return path 45a are mixed, and an adjustment tank 10 provided at the rear of the primary sludge charging tank 80, and adjustment A secondary sludge charging tank 40 provided in the rear of the tank 10 in which the sludge W and the sludge from the sludge return path 45 are mixed, and a rear sludge charging tank 40 provided on the rear side of the secondary sludge charging tank 40 from the adjustment tank 10 side. An aeration tank 20 that performs microbial treatment on sewage and a settling tank 30 that is provided on the rear side of the aeration tank 20 and precipitates sewage that has been microbially treated in the aeration tank 20. Between each of the sewage agitation tank 70, the primary sludge charging tank 80, the adjustment tank 10, the secondary sludge charging tank 40, and the aeration tank 20 and the subsequent tanks, the sewage in the tank is sent to the rear tank. Feeding paths 71, 81, 11, 41, 21 for feeding are provided.

The sewage agitation tank 70 is provided with an agitation fin 73 inside, and agitates the sewage in the sewage agitation tank 70. Further, the sewage agitation tank 70 is provided with a pump 72 that pumps the sewage into a feed path 71 that feeds the sewage to the primary sludge charging tank 80.
The sewage agitation tank 70 and the primary sludge input tank 80 are provided with a primary circulation path 90 for circulating the sewage in the sewage agitation tank 70 and the primary sludge input tank 80. The primary circulation path 90 is configured in substantially the same manner as the circulation path 50 of the sewage purification system S1 according to the above-described embodiment, and the supply path 71 provided between the sewage agitation tank 70 and the primary sludge charging tank 80; The first sewage return path 91 returns the sewage in the primary sludge charging tank 80 to the sewage agitation tank 70. The first sewage return path 91 is provided with a magnetic field applying device 60. Reference numeral 92 denotes a pump for pumping up sewage into the first sewage return path 91.

The sludge return path 45 is branched at the end side (45a) and connected to the primary sludge charging tank 80 and the secondary sludge charging tank 40 so that the sludge W settled in the settling tank 30 can be returned to the respective charging tanks 40, 80. It has become.
Further, a secondary circulation path 50 similar to the circulation path 50 of the sewage purification system S1 according to the above embodiment is provided. The secondary circulation path 50 includes a supply path 11 provided between the adjustment tank 10 and the secondary sludge charging tank 40, and a second sewage return path for returning the sewage from the secondary sludge charging tank 40 to the sewage agitation tank 70. 51.
Other configurations are the same as those described above.

When the sewage purification system S <b> 1 according to the second embodiment is used, sewage from the food processing factory 1 flows into the sewage agitation tank 70.
This sewage is pumped up by a pump 72 in the sewage agitation tank 70 and is fed to the primary sludge charging tank 80 through the feed path 71. Moreover, the sludge W settled in the settling tank 30 flows into the primary sludge charging tank 80 through the sludge return path 45, and the sludge W is thrown into the sewage. Then, similarly to the circulation path 50 of the first embodiment, the sewage is circulated between the sewage agitation tank 70 and the primary sludge charging tank 80 by the primary circulation path 90, and the agitation fins 73 of the sewage agitation tank 70 are used. The sludge W is well mixed with the sewage by stirring or the like.

In the primary circulation path 90, the magnetic field from the magnetic field applying device 60 is applied to the sewage when passing through the pipe 61 that is the primary sewage return path 51.
At this time, since the sewage flowing into the sewage agitation tank 70 contains a large amount of suspended solids, these may gather together to form a so-called scum assembly. The scum is dispersed and the sewage is circulated between the sewage agitation tank 70 and the primary sludge charging tank 80 in a state where the organic matter is in the sewage as much as possible.
Then, the sewage in the primary sludge charging tank 80 is caused to flow into the adjustment tank 10 by overflow in a state where the size of the suspended solids is reduced to some extent.
At this time, since the suspended matter in the sewage is refined in advance in the tank on the front side of the adjustment tank 10 and the size thereof is reduced, the adjustment tank 10, the secondary sludge charging tank 40, and the circulation path 50, the load related to the refining of suspended solids is reduced. Therefore, even if there is a large amount of suspended solids in the sewage, organic substances are smoothly refined in the adjustment tank 10, the secondary sludge charging tank 40, and the circulation path 50, and the purification efficiency is improved.
Other operations and effects are the same as those of the first embodiment.

Next, the sewage purification system proposed in the development stage of the present invention will be described.
As shown in FIG. 9, this sewage purification system S3 is used when the amount of sewage from the food processing factory 1 or the like is relatively small, and the sewage purification system S1 of the first embodiment described above. The adjustment tank 10, the aeration tank 20, and the precipitation tank 30 are provided, but unlike the sewage purification system S1 of the first embodiment, the precipitation tank is provided at the rear of the adjustment tank 10. The sludge input tank 100 that mixes the sludge W that has settled in 30 and the sewage that flows in from the adjustment tank 10, and the sewage agitation that is provided between the sludge input tank 100 and the aeration tank 20 and stirs the sewage that flows in from the sludge input tank 100 And a tank 110. The sewage purification system S3 includes the adjustment tank 10 and the sludge charging tank 100, the sludge charging tank 100 and the sewage stirring tank 110, the sewage stirring tank 110 and the aeration tank 20, and the aeration tank. Between 20 and the sedimentation tank 30, the supply path 11,101,111,21 which supplies sewage to the tank of a back | latter side is provided, and sewage in order toward the tank of a back | latter side from the adjustment tank 10 is provided. Can be shed.

A feeding path 101 between the sludge charging tank 100 and the sewage agitation tank 110, which is a tank on the front side of the aeration tank 20, is provided with a magnetic field applying device 60 that applies a magnetic field to the sewage flowing therethrough. . As shown in FIGS. 2 to 6, the magnetic field applying device 60 includes a communication pipe 61 that forms a part of the feed path 101 and a single circumference outside the communication pipe 61, as described above. And a magnetic field generator 62 including a plurality of electromagnets 62a, 62b, 62c, 62d, 62e, and 62f that generate a magnetic field, and a power source 64 that supplies current to the electromagnets 62a, 62b, 62c, 62d, 62e, and 62f. Configured.
The sludge input tank 100 is provided with a sludge return path 105 for returning the sludge W precipitated in the settling tank 30.
Furthermore, the sewage agitation tank 110 is provided with an agitation pump 112 for agitating the sewage in the sewage agitation tank 110.
Other configurations are the same as those described above.

When this sewage purification system S3 is used, the sewage from the food processing plant 1 flows into the adjustment tank 10, and this sewage is pumped by the pump 12 in the adjustment tank 10 and passes through the feed path 11 to the sludge input tank 100. To be sent to. Moreover, the sludge W settled in the settling tank 30 flows into the sludge charging tank 100 via the sludge return path 45, and the sludge W is thrown into the sewage. And the sewage of the sludge input tank 100 flows into the sewage agitation tank 110 through the feed path 101 from the sludge input tank 100 by overflow.
At this time, since the magnetic field applying device 60 is provided in the feeding path 101, the floating substance, which is an organic substance, is refined by the magnetic field in the same manner as described above. Moreover, it refines | miniaturizes also by the predation etc. of the enzyme in the sludge W, the enzyme newly synthesized by the microorganism, and the microorganism.

In the sewage agitation tank 110, the sewage is agitated by the agitation pump 112, the microorganisms in the sludge W and the sewage are well mixed, the suspended matter is refined by the microorganisms and enzymes, and the organic matter is dissolved. Organic matter is taken up by microorganisms.
Thereafter, the sewage is fed to the aeration tank 20.

When the air is blown into the aeration tank 20 and air is blown into the aeration tank 20 by the blower 22, most of the organic matter is dissolved in low molecular weight and taken up by microorganisms. When air is supplied to the sewage in the aeration tank 20 at 22, microorganisms grow by cell division or the like using the taken-in organic matter as nutrients, and most of the organic matter becomes carbon dioxide and water in the growth process.
Then, the sewage is fed from the aeration tank 20 to the sedimentation tank 30 by the overflow through the feeding path at an appropriate time.

In the settling tank 30, suspended substances and microorganisms are gathered to form a so-called floc, and the floc is precipitated, while the supernatant is discharged into the river 5 and the like. The suspended matter and microorganisms that have settled in the sedimentation tank 30 are sent to the sludge input tank 100 through the sludge return path 45 as sludge W.
Other operations and effects are the same as those described above.

It is a figure which shows the purification system of the sewage which concerns on 1st embodiment of this invention. It is a figure which shows the magnetic field provision apparatus of the purification system of the sewage which concerns on 1st embodiment of this invention. It is a figure which shows the AA line cross section in FIG. 2 of the magnetic field provision apparatus of the purification system of the sewage which concerns on 1st embodiment of this invention. It is a figure which shows the magnetic field provision apparatus of the purification system of the sewage which concerns on 1st embodiment of this invention. It is a block diagram which shows the system of the magnetic field provision apparatus of the purification system of the sewage which concerns on 1st embodiment of this invention. It is a graph which shows the voltage applied to the electromagnet of the sewage purification system which concerns on 1st embodiment of this invention. In the sewage purification system which concerns on 1st embodiment of this invention, it is a figure which shows the state of the organic substance in sewage. It is a figure which shows the purification system of the sewage which concerns on 2nd embodiment of this invention. It is a figure which shows the purification system of the sewage proposed in the development stage of this invention. It is a figure which shows an example of the purification system of the conventional sewage.

Explanation of symbols

S1, S2, S3 Sewage purification system 10 Adjustment tank 20 Aeration tank 30 Sedimentation tank 40 Sludge input tank (secondary sludge input tank)
W Sludge 45 Sludge return path 50 Circulation path (Primary circulation path)
51 Wastewater return route (second wastewater return route)
52 Pump 53 Scattering mechanism 60 Magnetic field applying device 61 Pipe 62 Magnetic field generator 62a, 62b, 62c, 62d, 62e, 62f Electromagnet 63 Substrate 65 Pulse voltage generating means 66 Sequential excitation means 70 Sewage agitation tank 80 Primary sludge charging tank 90 Primary Circulation path 100 Sludge input tank 101 Feeding path

Claims (7)

An adjustment tank into which sewage flows, an aeration tank provided on the rear side of the adjustment tank for performing microbial treatment on the sewage from the adjustment tank side, and a microbial treatment in the aeration tank provided on the rear side of the aeration tank In a sewage purification system comprising at least three tanks with a settling tank for precipitating treated sewage,
Provide a circulation path for circulating sewage in the tank on the front side of the aeration tank,
A magnetic field applying device that applies a magnetic field to the sewage flowing through the circulation path is provided.
Provide a sludge return path for returning sludge settled in the settling tank in the tank provided with the circulation path,
Between the adjustment tank and the aeration tank, a sludge charging tank for mixing the sludge from the adjustment tank and the sludge returned from the sedimentation tank by the sludge return path is provided.
The circulation path comprises a supply path for feeding the sewage in the adjustment tank to the sludge input tank, and a sewage return path for returning the sludge in the sludge input tank to the adjustment tank,
A sewage purification system, wherein the magnetic field applying device is provided in the sewage return path of the circulation path . An adjustment tank into which sewage flows, an aeration tank provided on the rear side of the adjustment tank for performing microbial treatment on the sewage from the adjustment tank side, and a microbial treatment in the aeration tank provided on the rear side of the aeration tank In a sewage purification system comprising at least three tanks with a settling tank for precipitating treated sewage,
Provide a circulation path for circulating sewage in the tank on the front side of the aeration tank,
A magnetic field applying device that applies a magnetic field to the sewage flowing through the circulation path is provided.
Provide a sludge return path for returning sludge settled in the settling tank in the tank provided with the circulation path,
A sewage agitation tank for agitating sewage is provided in front of the adjustment tank, and the sewage from the sewage agitation tank and the sludge returned from the sedimentation tank by the sludge return path are mixed and sent to the adjustment tank. Set up a primary sludge charging tank,
Between the adjustment tank and the aeration tank, a secondary sludge charging tank that mixes the sludge from the adjustment tank and the sludge returned from the sedimentation tank by the sludge return path is provided.
The circulation path is configured with a primary circulation path and a secondary circulation path,
The primary circulation path includes a supply path for feeding the sewage in the sewage agitation tank to the primary sludge input tank, and a first sewage return path for returning the sewage in the primary sludge input tank to the sewage agitation tank. And configure
The secondary circulation path includes a supply path for feeding the sewage from the adjustment tank to the secondary sludge input tank, and a second sewage return path for returning the sewage from the secondary sludge input tank to the adjustment tank. Configure and prepare
A sewage purification system, wherein the magnetic field applying device is provided in each of the first sewage return path of the primary circulation path and the second sewage return path of the secondary circulation path.   The magnetic field applying device includes a through-tube through which sewage passes, a magnetic field generating unit including a plurality of electromagnets provided on one circumference outside the through-tube and generating a magnetic field, and a power source for supplying current to the electromagnet. The sewage purification system according to claim 1 or 2, wherein the system is configured as described above.   4. The sewage purification system according to claim 3, wherein the magnetic field generation unit is configured by providing a plurality of sets of a pair of electromagnets provided in line symmetry about the axis of the pipe and having different polarities.   The sewage purification system according to claim 4, further comprising pulse voltage generation means for applying a pulsed voltage to the pair of electromagnets to form a pulsed magnetic field by the pair of electromagnets.   6. The sewage purification system according to claim 4 or 5, further comprising sequential excitation means for sequentially exciting the electromagnet groups.   The sewage purification system according to claim 3, 4, 5, or 6, wherein a plurality of the magnetic field generation units are arranged in the axial direction of the pipe.

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