JP6245323B2 - Organic wastewater biological treatment equipment - Google Patents

Description

  The present invention relates to a biological treatment apparatus for organic wastewater that can be widely used for the treatment of organic wastewater such as domestic wastewater, sewage, food factories, pulp factories, semiconductor production wastewater, and liquid crystal production wastewater. The present invention relates to a biological treatment apparatus for organic wastewater provided with a biological treatment tower for biologically treating water. Moreover, this invention relates to the biological treatment method of the organic waste water using this processing apparatus.

The activated sludge method used when biologically treating organic wastewater is widely used for sewage treatment, industrial wastewater treatment, and the like because of its advantages such as good treated water quality and easy maintenance. However, since the BOD volumetric load in the activated sludge method is generally about 0.5 to 0.8 kg / m ³ / d, a large site area is required. Moreover, since 20 to 40% of the decomposed BOD is converted into microbial cells, that is, sludge, a large amount of excess sludge treatment is also a problem.

For high load treatment of organic waste water, a fluidized bed method with a carrier added is known. When this method is used, it is possible to operate with a BOD volume load of ³ kg / m ³ / d or more. However, this method has a disadvantage that the amount of generated sludge is about 30 to 50% of the decomposed BOD and is higher than that of the normal activated sludge method.

  In Patent Document 1, organic wastewater is first treated with bacteria in a first treatment tank, and organic matter contained in the wastewater is oxidatively decomposed and converted into non-aggregating bacterial cells, and then in a second treatment tank. It is described that excess sludge can be reduced by predatory removal of the sticking protozoa. Further, this method enables high-load operation and improves the processing efficiency of the activated sludge method.

  In this way, many wastewater treatment methods have been devised that use the predation of protozoa and metazoans located at high levels of bacteria. For example, Patent Document 2 describes a countermeasure against deterioration in processing performance due to fluctuations in the quality of raw water, which is a problem in the processing method of Patent Document 1. As specific methods, “adjust BOD fluctuation of treated water to within 50% from median average concentration”, “measure water quality in first treatment tank and first treated water over time”, The method includes “adding a microbial preparation or seed sludge to the first treatment tank when the quality of the first treated water deteriorates”.

  In Patent Document 3, flocs that are preyed by ultrasonic treatment or mechanical agitation when protozoa or metazoans prey on bacteria, yeast, actinomycetes, algae, molds, wastewater treatment primary sludge or surplus sludge. A method to make the flock size smaller than the animal's mouth is proposed.

  There exists a thing of patent document 4 as a biological treatment method of the organic waste_water | drain by the multistage process of a fluidized bed and an activated sludge process. In this method, the latter activated sludge method is operated at a low load of BOD sludge load 0.1 kg-BOD / kg-MLSS / d, so that the sludge can be self-oxidized and the amount of sludge extraction can be greatly reduced.

  As a tank body of a conventional biological treatment tank, a concrete water tank or a tower-like elevated water tank is used.

The concrete tank has the following problems.
(B) The tank body will be used for civil engineering work, and the tank internal equipment will be installed after the tank construction. Concerns remain in terms of construction and quality control.
(B) Since the water depth is practically up to about 4 m in practice, the installation space at the site becomes large.
(C) Even if it is desired to reinforce equipment in response to an increase in raw water load, it cannot be easily expanded due to local civil engineering work and large installation area.
(D) It is difficult to check for liquid leakage from the bottom.
(E) It is necessary to repair the tank inner lining.

The tower-shaped elevated tank has the following problems.
(F) In order to secure the capacity while suppressing the installation space, it is necessary to increase the tank height, and at least about 7 m is required. In this case, it is necessary to climb to the upper part of the tank during on-site piping construction and daily maintenance, and usually a staircase or a ladder is installed. For this reason, workability | operativity worsens.
(G) The burden of the transition piping work from the upper part of the tank in the field tends to increase.
(H) Depending on the tank material and liquid quality, it is necessary to repair the tank inner lining.

Japanese Patent Laid-Open No. 55-20649 JP 2000-210692 A Japanese Patent Publication No. 60-23832 Japanese Patent No. 3410699

As described above, the conventional concrete tank or tower-shaped elevated tank has the following problems.
1) The installation area of the concrete tank is large.
2) The construction period will be longer in concrete tanks.
3) It is not easy to reinforce equipment in a concrete tank.
4) Tower-type water tanks with large tank heights have poor work efficiency due to work at high places, and it is necessary to improve workability and prevent falling accidents.
5) In tower-type water tanks with large tank heights, piping from the top of the tank to the outside will be generated, increasing the burden of on-site construction, so it is necessary to simplify on-site construction.

  An object of the present invention is to solve these problems, and to provide a biological treatment apparatus and treatment method for organic wastewater that is easy to construct and can reduce work at high places and save space. .

  It is another object of the present invention to provide an organic wastewater biological treatment apparatus and treatment method that can easily cope with various changes in raw water quality, required water quality, and increased amount of treated water.

  The organic wastewater biological treatment apparatus of the present invention is an apparatus for biologically treating organic wastewater in a biological treatment tank provided in multiple stages. In the first biological treatment tank, the organic wastewater is dispersed by decomposing organic matter by dispersal bacteria. A biological treatment apparatus for organic waste water that produces first biological treated water with increased fungi and produces second biological treated water in a second biological treated tank at a later stage, wherein the first biological treated tank and the second biological treated water are produced. The treatment tank has towers of the same shape and the same size, and the height of the towers is 6 to 11 m.

  In this invention, it is preferable that ratio (H / D) of the height (H) and diameter (D) of a tower body is 1.5-5.0. Moreover, in this invention, it is preferable that the installation height TOP (TOP of pipe) of a manhole and most, for example, half or more of pipe connection parts, is 3 m or less.

  In this invention, you may install two or more 1st biological treatment tanks and 2nd biological treatment tanks in parallel.

  In the present invention, the tower body is preferably made of FRP and is integrally formed as a whole from the tower bottom to the tower top.

  In this case, it is preferable that the thickness of the lower part of the tower body is larger than the thickness of the upper part of the tower body. Moreover, it is preferable that at least a part of the vertical piping has a half-cylindrical shape and is bonded to the inner peripheral surface of the tower body.

  The organic wastewater biological treatment method of the present invention uses the biological treatment apparatus of the present invention.

  The organic wastewater treatment apparatus of the present invention is provided with a plurality of water treatment units having towers of standard dimensions (same shape, same size), and each water treatment unit is manufactured in advance in a factory. I can leave.

  In the present invention, since the sizes of the tanks are unified, the design and construction of the apparatus are also made common and can be performed easily and quickly. Moreover, the space between tanks can also be made small. Furthermore, it is easy to add a biological treatment tank.

  By constructing the tower body integrally with FRP, the weight is reduced, and transportation and installation work are also facilitated. In this case, the strength, pressure resistance, and durability of the tower can be increased by increasing the thickness of the lower part of the tower. In addition, by making the vertical piping into a half-cylindrical shape and adhering to the circumferential surface of the tower body, the structure inside the tower body can be simplified, and the water circulation flow inside the tower body can be made smooth. Also, the installation strength of the vertical piping is increased.

  In one embodiment of the present invention, the joint locations and manholes of most pipes are provided in the lower part of the tower (the height of the ground is 4 m or less), so the number of work at high places is small.

  In one embodiment of the present invention, biological treatment tanks are provided in multiple stages, the biological treatment tank in the previous stage is a dispersion bacteria tank that converts organic matter into dispersal bacteria, and the last biological treatment tank has an adhesive property that prey on the dispersal bacteria. A carrier is provided as a scaffold for filtered predatory microanimals. In this treatment, the micro-animal can be stably maintained, and the treated water quality can be stabilized.

It is a longitudinal cross-sectional view of the biological treatment apparatus of the organic waste_water | drain which concerns on embodiment. It is the II-II arrow directional view of FIG. It is the III-III arrow directional view of FIG. It is a top view which shows the example of water treatment unit arrangement | positioning in the biological treatment apparatus of the organic waste_water | drain of this invention. It is a longitudinal cross-sectional view of the biological treatment apparatus of the organic waste_water | drain which concerns on another embodiment. (A) is the sectional view on the AA line of FIG. 5, (b) is the sectional view on the BB line of FIG. It is the VII-VII sectional view taken on the line of FIG. It is a VIII-VIII arrow line view of FIG. (A) is a block diagram which shows another embodiment, (b) is the IXb-IXb sectional view taken on the line of (a). It is a block diagram which shows another embodiment.

  DESCRIPTION OF EMBODIMENTS Embodiments of an organic wastewater biological treatment apparatus and treatment method of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows an embodiment of a biological treatment apparatus for organic wastewater according to the present invention. A first biological treatment tank 1 and a second biological treatment tank 2 are erected on a foundation 3 and are connected by a pipe 4. Connected in series.

  The first biological treatment tank 1 is connected to the cylindrical tower 10, the raw water inlet 11 a having a flange structure provided on the lower side surface of the tower 10, and the raw water inlet 11 a, The raw water introduction pipe 11 whose upper end is opened above the outlet 14 a, the air diffusion pipe 12 provided at the bottom of the tower body 10, and the upper side of the air diffusion pipe 12 in the tower body 10 The fixed bed or rocking bed carrier 13 installed in the upper part of the tower body 10 and the treated water outlet 14a provided at the upper part of the tower body 10 are provided. The air diffuser 12 is connected to a blower (not shown) as a gas supply device. Here, as the blower, when the water level is high, a high pressure blower having a capability of a discharge pressure of 60 kPa or more such as a screw blower or a turbo blower is preferable.

  The outflow pipe 14 is connected to the outflow port 14a. The outflow pipe 14 extends downward along the outer surface of the tower body 10, and the lower end is a pipe connection part 14b having a flange structure. As shown in FIG. 2, a crank-shaped bent portion 14c is provided in the middle of the outflow pipe 14 in the vertical direction.

  An opening 15 a is provided at the top of the tower body 10, and one end of the atmosphere communication pipe 15 is connected thereto. As shown in FIG. 2, the atmosphere communication pipe 15 extends downward on the outer surface of the tower body 10 along the tower body 10, and the lower end 15 b is opened downward in the immediate vicinity of the foundation 3. The upper end of the outflow pipe 14 communicates with the laterally extending portion 15b of the atmospheric communication pipe 15 through an inverted U-shaped communication pipe 14d.

  As shown in FIG. 2, a preliminary seat 16 is provided at the top of the tower body 10, and a manhole 17 and a preliminary seat 18 are provided at the lower portion.

  The second biological treatment tank 2 includes a cylindrical tower body 20 having the same shape and size as the tower body 10, a flanged structure inlet 21 provided on the lower side surface of the tower body 20, and the inside of the tower body 20. A diffuser tube 22 provided at the bottom of the column 20 and a strainer 23 installed in the middle in the vertical direction of the tower body 20 or below it. The inflow port 21 is connected to the pipe connection portion 14b through the pipe 4. The air diffuser 22 is connected to a blower (not shown). This blower is shared with a blower for supplying air to the air diffuser 12.

  An outflow pipe 24 is connected to the strainer 23. As shown in FIG. 3, the outflow pipe 24 rises up to the same level as the outlet 14a of the first biological treatment tank 10 along the outer surface of the tower body 20, and one end side is connected to the upright part 24a in the horizontal direction. A laterally extending portion 24b led to the other end side of the laterally extending portion 24b, and an upright portion 24c extending to the vicinity of the foundation 3 along the outer surface of the tower body 20, The lower end of the lower part 24c is an outlet 24d. An air release pipe 24e extends upward from the upper end of the rising portion 24a of the outflow pipe 24, and the upper end of the air release pipe 24e is open to the atmosphere. A crank-shaped bent portion 24 f is provided in the middle of the standing portion 24 c of the outflow pipe 24.

  An opening 25 a is provided at the top of the tower body 20, and one end of the atmosphere communication pipe 25 is connected thereto. As shown in FIG. 3, the atmosphere communication pipe 25 extends downward on the outer surface of the tower body 20 along the tower body 20, and the lower end 25 b is opened downward in the immediate vicinity of the foundation 3.

  As shown in FIG. 3, a preliminary seat 26 is provided at the top of the tower body 20, and a manhole 27, a preliminary seat 28, and an air supply pipe 22 a to the diffuser pipe are provided at the lower portion. A fluidized bed carrier 29 is packed in the tower body 20. Reference numeral 27a denotes a maintenance manhole for the strainer 23.

  Each of the towers 10 and 20 is preferably made of a resin such as FRP because it does not require lining, but may be a steel plate depending on the water quality. In the case of FRP, it is preferable to apply a weather-resistant paint (for example, a tank stainless coat made by Torch Co., Ltd.) for the purpose of preventing deterioration due to ultraviolet rays and improving corrosion resistance. Moreover, when the tower bodies 10 and 20 are made of FRP, it is preferable to make the thickness of the lower part of the tower body where the water pressure becomes larger than that of the upper part. The upper and lower parts of the tower body may be thicker than the upper part, and the lower part may be thicker than that.

  The first and second biological treatment tanks 1 and 2 are provided with an excess sludge take-out pipe, a drain pipe, an insertion pipe for a monitoring camera in the tank, a wiring insertion opening, a sampling opening (not shown), and the like. Monitoring in the tank is performed by always or appropriately inserting a camera or a photographing device (preferably with illumination or an infrared camera) having a moving image shooting function into the tank. Shooting data is transmitted wirelessly or by wire. The photographing data may be stored in the photographing equipment. A heat insulating material may be wound around the tower in advance.

  If necessary, measuring instruments such as a water level gauge, pressure gauge, flow meter, water temperature gauge, water quality meter, etc. are installed in the water tank or peripheral equipment, piping, etc., and used for monitoring the operation status, operating control, operation management, etc. In addition, it is used for optimizing the treatment in the water tank in combination with incidental facilities (for example, facilities equipped with water supply, heating, chemical injection, aeration, dehydration functions, etc.).

  In order to treat organic wastewater with this organic wastewater biological treatment device, raw water (organic wastewater) is introduced into the first biological treatment tank 1 through the introduction pipe 11 and aerated through the aeration pipe 12 to be dispersible. Bacteria (non-aggregating bacteria) oxidatively degrade 70% or more of organic components (soluble BOD), desirably 80% or more, and more desirably 85% or more. The pH of the first biological treatment tank 1 is preferably 6 to 8.5. However, when the raw water such as food manufacturing wastewater contains a lot of oil, or when the raw water such as semiconductor manufacturing wastewater or liquid crystal manufacturing wastewater contains a lot of organic solvent or cleaning agent, the pH is 8 It is good also as ~ 9.

The water flow to the 1st biological treatment tank 1 shall be a transient type. The BOD volumetric load of the first biological treatment tank 1 is 1 kg / m ³ / d or more, for example 1 to 20 kg / m ³ / d, HRT (raw water retention time) is 24 h or less, preferably 8 h or less, for example 0.5 to 8 h By doing so, it is possible to obtain treated water predominated by dispersible bacteria, and by shortening the HRT, wastewater having a low BOD concentration can be treated with a high load.

Returning a part of sludge from the subsequent biological treatment tank to the first biological treatment tank 1, making the first biological treatment tank 1 a multistage configuration of two or more tanks, or installing a carrier 13. Thus, high load processing with a BOD volumetric load of 5 kg / m ³ / d or more is also possible. A fluid bed carrier may be filled as the carrier.

  When the carrier 13 is a rocking bed carrier, the material is preferably a foamed synthetic resin, particularly a flexible polyurethane foam. When a porous sheet-like oscillating bed carrier such as a thin plate-like or strip-like lightweight polyurethane foam is installed in the first biological treatment tank 1, the oscillating bed carrier has sufficient elasticity, Even if it is thin, it has sufficient mechanical strength and does not break by being bent in the flow of water in the tank. Moreover, by bending, it mixes uniformly, without inhibiting the water flow in a tank, and a sludge containing liquid comes to flow uniformly also into the porous structure of a support | carrier.

  When the filling rate of the carrier in the first biological treatment tank 1 is high, dispersal bacteria are not generated, and bacteria adhere to the carrier or filamentous bacteria grow. Therefore, the filling rate of the carrier added to the first biological treatment tank 1 is 10% or less, for example 1 to 10% in the case of a fluidized bed carrier, and 5% or less in the case of a fixed bed carrier or a rocking carrier, for example, By setting the content to 0.5 to 5%, it is possible to produce dispersal bacteria that are not affected by concentration fluctuation and are easy to eat.

  The dissolved oxygen (DO) concentration in the first biological treatment tank 1 may be 1 mg / L or less, preferably 0.5 mg / L or less to suppress the growth of filamentous bacteria.

  The treated water (first biological treated water) in the first biological treatment tank 1 is introduced into the second biological treatment tank 2 in the subsequent stage through the outlet 14a, the pipes 14, 4 and the inlet 21, and aerated and remains. The amount of excess sludge is reduced by oxidative degradation of organic components, self-degradation of dispersible bacteria, and predation of minute animals. The treatment liquid in the second biological treatment tank 2 is taken out via the strainer 23 and the outflow pipe 4.

  In the second biological treatment tank 2, it is necessary to use an operation condition and a treatment apparatus that allow the microanimal and the bacteria to remain in the system in order to use the action of the microanimal having a slower growth rate than the bacteria and the autolysis of the bacteria. . Therefore, in this embodiment, the second biological treatment tank 2 is filled with a fluidized bed carrier 29 to increase the amount of minute animals retained in the tank.

  The shape of the fluidized bed carrier 29 is arbitrary such as a spherical shape, a pellet shape, a hollow cylindrical shape, a thread shape, and a plate shape, and the size (diameter) is about 0.1 to 10 mm. The material of the carrier 29 is arbitrary such as a natural material, an inorganic material, or a polymer material, and a gel material may be used. The carrier is not limited to a fluidized bed carrier, and may be either a fixed bed carrier or a rocking carrier, and two or more kinds of carriers may be used in combination.

  In the second biological treatment tank 2, a large amount of scaffolding for maintaining micro-animals is required. However, if the filling rate of the carrier is excessively high, mixing in the tank, sludge decay, etc. may occur. The filling rate is preferably 0.5 to 30%, particularly preferably about 1 to 10%.

  In order to promote predation by the minute animals, the pH of the second biological treatment tank 2 may be 7.0 or less.

  In the second biological treatment tank 2, not only the filtration predation type micro-animal that prey on the dispersed cells, but also the aggregate predation type micro-animal that can prey on the flocked sludge grows. Since the latter prey on flocs while swimming, if priority is given, sludge is eaten and becomes sludge in which fine floc pieces are scattered (sludge with poor sedimentation). In addition, this floc piece causes clogging of the membrane particularly in the membrane activated sludge method in which membrane separation is performed in the latter stage. Therefore, in order to thin out the aggregate predatory microanimals, it is desirable to control the SRT to be constant within a range of 60 days or less, preferably 45 days or less. However, if it is less than 15 days, it is unnecessarily frequent, and the number of not only aggregate predation type micro-animals but also filtration predation type micro-animals is excessively reduced.

  In the first biological treatment tank 1, it is necessary to decompose most of the organic matter, that is, 70% or more of the wastewater BOD, desirably 80% or more, and convert it into microbial cells. When the organic substances are completely decomposed, flocs are not formed in the second biological treatment tank 2, and there is not enough nutrients for the growth of micro-animals. Only sludge with poor compaction (sludge with poor sedimentation) is excellent. It becomes an occupied biological treatment tank. Therefore, a part of the raw water is bypassed and supplied to the second biological treatment tank 2 so that the sludge load due to the soluble BOD in the second biological treatment tank 2 is 0.025 kg-BOD / kg-MLSS / d or more. You may drive. The MLSS at this time includes MLSS for the carrier adhering.

  For the treated water taken out from the second biological treatment tank 2 through the strainer 23 and the piping 24, any of membrane separation, coagulation sedimentation, and pressurized flotation is performed as solid-liquid separation in order to obtain a higher quality of treated water. May be. In addition, when performing coagulation sedimentation or pressure levitation, the amount of coagulant added can be reduced. The sedimentation water from the second biological treatment tank 2 may be agglomerated in a coagulation tank, and then precipitated in a solid-liquid separation tank (sedimentation tank) to separate into treated water and sedimented sludge.

  In order to remove foreign matter adhering to the strainer 23, a backwash air supply pipe may be connected to the pipe 24. In this way, even if the strainer 23 is installed in the lower part of the tower body, the deposits can be easily removed. In addition, by installing the strainer 23 in the lower part of the tower body, it is possible to prevent floating foreign substances such as fats and oils from adhering to the strainer.

  With reference to FIGS. 5-8, the biological treatment apparatus of the organic waste_water | drain which concerns on another embodiment of this invention is demonstrated. As shown in FIG. 5, also in this organic wastewater biological treatment apparatus, the first biological treatment tank 41 and the second biological treatment tank 42 are erected on the foundation 43 and connected in series by a pipe 70.

  The first biological treatment tank 41 includes an FRP cylindrical tower body 50, a raw water (treated water) inlet 51 a having a flange structure provided on the lower side surface of the tower body 50, and the raw water inlet 51 a. A raw water introduction pipe 51 that extends upward along the inner peripheral surface of the tower body 50 and has an upper end opened higher than the water surface level, and an aeration pipe 52 provided at the bottom of the tower body 50, The air pipe 53 for connecting the diffuser pipe 52 to a blower (not shown), the siphon break pipe 53A connected in the middle of the air pipe 53, and a plurality of the pipes 50 provided in the middle in the vertical direction of the tower body 50 or in the lower order. Strainers 54, 54, a connection pipe 55 that connects the strainers 54, a treated water outlet 56 that communicates with the connection pipe 55, and a drain pipe that extends in the vertical direction along the inner peripheral surface of the tower body 50. 57 and provided vertically in the tower body 50 The has an injection pipe 58 and the like of the antifoam solution.

  An opening 50a is provided at the top of the tower body 50, and the inside of the tower body 50 communicates with the atmosphere through the opening 50a.

  As shown in FIG. 6A, the raw water introduction pipe 51 has a half-cylindrical shape and is bonded to the inner peripheral surface of the tower body 50. As described above, the upper end of the raw water introduction pipe 51 is open into the tower body 50 above the water level. The lower end of the raw water introduction pipe 51 is sealed. A raw water inlet 51 a provided so as to penetrate the lower side wall of the tower body 50 communicates with a lower end portion in the raw water introduction pipe 51.

  One end side of the air pipe 53 penetrates the lower part of the tower body 50 and protrudes outside the tower body 50, and an air supply pipe from the blower is connected to the tip of the air pipe 53. The other end of the air pipe 53 is connected to the diffuser pipe 52.

  The air pipe 53 rises above the water surface level in the tower body 50, and one end of a siphon break pipe 53A is connected to the highest portion 53b of the rise. The siphon break pipe 53 </ b> A is routed downward in the tower body 50, and the other end side penetrates the lower part of the tower body 50 and projects out of the tower body 50. A valve 53a is provided at the tip of the siphon break pipe 53A.

  The strainer 54 is installed near the middle in the vertical direction of the tower body 50 or below it. As shown in FIG. 7, the strainer 54 includes a box 54a attached by being bonded to the inner peripheral surface of the tower body 50, and a screen 54b made of a wedge wire or the like provided on the front surface of the box 54a. The rear surface of the box 54 a is open, and the rear end of the box 54 a is bonded to the inner peripheral surface of the tower body 50.

  In this embodiment, two strainers 54 are provided so as to be separated from each other in the vertical direction, and the inside of each strainer 54 is communicated by a connection pipe 55.

  This connection pipe 55 is also a half cylinder, and is bonded to the inner peripheral surface of the tower body 50. The treated water outlet 56 communicates with the connection pipe 55 through an opening provided in the tower body 50.

  Although illustration is omitted, a hand hole is provided in the tower body 50 in order to maintain the inside of the strainer 54.

  The drain pipe 57 extends in the vertical direction along the inner peripheral surface of the tower body 50. The drain pipe 57 has a half-cylindrical shape as shown in FIG. 6B except for the uppermost part, and is adhered to the inner peripheral surface of the tower body 50. The uppermost part of the drain pipe 57 has a cylindrical shape and opens into the tower body 50 above the water level. The lower end portion of the drain pipe 57 communicates with the drain outlet 57 at the lower part of the tower body 50.

  The defoamer water injection pipe 58 is routed in the vertical direction in the tower body 50, and the upper end portion is bent in a substantially U shape so as to face downward, above the water level in the tower body 50. It is open. The lower end of the water injection pipe 58 penetrates the tower body 50 and protrudes outside the tower body 50.

  The second biological treatment tank 42 has all the configurations of the first biological treatment tank 41, and the same reference numerals are given to the same parts as the first biological treatment tank 41.

  The second biological treatment tank 42 includes a treated water extraction pipe 60 connected to the treated water outlet 56 in addition to the above-described configuration of the first biological treatment tank 41. The treated water extraction pipe 60 is drawn upward outside the tower body 50, then passes through the side wall of the tower body 50 and is drawn into the tower body 50, and above the water surface of the second biological treatment tank 10. A rising portion 61 that rises up to one end, a horizontal extending portion 62 that is connected to the rising portion 61 at one end side, and is connected to the other end side of the horizontal extending portion 62 and extends to the lower portion in the tower body 50. And has an upright portion 63 protruding out of the tower body 50, and the end of the upright portion 63 serves as an outlet 64.

  The upper end 61 a of the upright portion 61 is curved downward and is open in the tower body 50. For this reason, the level of the horizontal drawing portion 62 becomes the water level in the second biological treatment tank 42. Further, since the outlet 56 of the first biological treatment tank 41 and the inflow port 51a of the second biological treatment tank 42 communicate with each other through the pipe 70, the water level in the first biological treatment tank 41 is the second biological treatment tank. It becomes the same as the water level of 42.

  As shown in FIG. 6B, the rising portion 61 and the falling portion 63 extend in the vertical direction along the inner peripheral surface of the tower body 50. The upright portion 61 and the upright portion 63 have a half-cylindrical shape, and are connected to the inner peripheral surface of the tower body 50.

  Two valves 66 and 67 are provided in a portion of the pipe 60 that is routed outside the tower body 50. An air supply pipe 68 having a valve 68 a is connected between the valves 66 and 67. A sampling pipe 69 for taking out sample water is connected between the valves 66 and 67. The pipe 69 is provided with a valve 69a.

  Two valves 71 and 72 are provided in a pipe 70 that connects the treated water outlet 56 of the first biological treatment tank 41 and the inlet 51 a of the second biological treatment tank 42. An air supply pipe 73 having a valve 74 is connected between the valves 71 and 72.

  In addition, although illustration is abbreviate | omitted, in the 1st and 2nd biological treatment tanks 41 and 42, the extraction pipe | tube of a surplus sludge, the insertion pipe | tube of a surveillance camera in a tank, a wiring penetration opening, a manhole, a spare seat (not shown), etc. Is provided.

  The first and second biological treatment tanks 41 and 42 are filled with a fluidized bed carrier. As the fluidized bed carrier, the same one as in the above embodiment can be used.

  In order to treat organic wastewater with this organic wastewater treatment apparatus, raw water (organic wastewater) is introduced into the first biological treatment tank 51 via the introduction pipe 51 of the first biological treatment tank 41, and the diffuser pipe 52. And 70% or more, desirably 80% or more, more desirably 85% or more of the organic component (soluble BOD) is oxidatively decomposed by dispersible bacteria (non-aggregating bacteria). Note that the valve 53a of the pipe 53A is closed during aeration. Suitable conditions such as pH, BOD volume load, carrier filling rate, dissolved oxygen (DO) concentration, etc. of the first biological treatment tank 41 are the same as those in the embodiment of FIGS.

  The treated water (first biological treated water) of the first biological treatment tank 41 is introduced from the outlet 56 into the second biological treatment tank 42 in the subsequent stage via the pipe 70, aerated, and the remaining organic components are oxidized. Reduce excess sludge by decomposition, self-degradation of dispersible bacteria and predation of micro-animals. At this time, the valves 71 and 72 of the pipe 70 and the valves 66 and 67 of the pipe 60 are opened.

  The suitable carrier filling rate, pH, SRT, and sludge load due to the soluble BOD in the second biological treatment tank 42 are the same as in the above embodiment.

  The air during aeration in the first and second biological treatment tanks 41 and 42 is discharged outside the tower through the opening 50a at the top of the tower. Bubbles generated during aeration are discharged to the drain pit outside the tower body 50 through the pipe 57. A foam sensor is provided in this drainage pit, and when there are many bubbles, an antifoaming agent or water is injected.

  In this embodiment, when the screen 54b of the strainer 54 of the first biological treatment tank 41 is clogged, the valve 72 is closed, the valve 74 is opened, and air is supplied from the air supply pipe 73 to the strainer of the first biological treatment tank 41. 54 is supplied and backwashed with air. When the screen 54b of the strainer 54 of the second biological treatment tank 42 is clogged, the valve 67 is closed, the valve 68a is opened, and air is supplied from the air pipe 68 into the strainer 54 of the second biological treatment tank 42. Backwash. Thus, since the strainer 54 can be easily washed with air, the washing is easy even if the strainer 54 is installed in the lower part of the tower. By installing the strainer 54 in the lower part of the tower body, it is possible to prevent floating foreign matters such as oil and fat from adhering to the strainer 54.

  When the operation of the biological treatment apparatus is stopped, each valve 53a is opened to prevent the water in the biological treatment tanks 41 and 42 from flowing backward in the pipe 53 due to the siphon phenomenon.

  5-8, although the strainer 54 is installed in the upper and lower two stages, you may install in one stage or three or more stages. A plurality of strainers may be provided at the same level. An example is shown in FIGS.

  In FIG. 9, two strainers 54, 54 are installed at the same level, their lower portions are connected by a pipe 55, and a treated water outlet 56 is provided so as to communicate with the pipe 55. 9A is a side view of a portion of the tower body 50 where the strainer 54 is provided, and FIG. 9B is a cross-sectional view taken along the line IXb-IXb in FIG. 9A.

  In FIG. 10, two strainers 54 and 54 are installed at the same level, and treated water extraction pipes 80 and 80 are connected to the lower portions of the two strainers 54 and 54, respectively. The pipes 80, 80 are routed upward, and merge in the tower body 50 to form an upright part, through a horizontal drawing part, to form a upright part 81, and a lower end thereof communicates with the outlet 56. FIG. 10 is a side view of a portion of the tower body 50 where the strainer 54 is provided.

  1-3 and 5-10 show an example of embodiment of this invention, and this invention is not limited to the thing of illustration at all. For example, the biological treatment tank may be provided in three or more stages by providing a third biological treatment tank after the first biological treatment tank 1, 41 or the second biological treatment tank 2, 42.

  FIG. 4 is a plan view showing various arrangement patterns of the first biological treatment tank 1 and the second biological treatment tank 2. FIG. 4A shows the first biological treatment tank 1 and the second biological treatment tank 2 installed one by one and connected in series. FIG. 4B shows a case where one first biological treatment tank 1 is installed and a plurality of second biological treatment tanks 2 are installed in parallel. FIG. 4C shows a case where a plurality of first biological treatment tanks 1 are installed in parallel and one second biological treatment tank 2 is installed. FIG. 4 (d) shows a plurality of serially connected bodies of the first biological treatment tank 1 and the second biological treatment tank 2 installed in parallel.

  4 (e) and 4 (f) show a plurality of first biological treatment tanks 1 installed in parallel and a plurality of second biological treatment tanks 2 installed in parallel. In FIG. The number of tanks 1 is greater than that of the second biological treatment tank 2, and the number of second biological treatment tanks 2 is greater than that of the first biological treatment tank 1 in (f). Although illustration is omitted, the first biological treatment tank 1 and the second biological treatment tank 2 may be the same number.

  FIG. 4G shows a plurality of second biological treatment tanks 2 and 2 'installed in series. FIG. 4 (h) shows a plurality of the devices shown in FIG. 4 (g) installed in parallel.

  When the first biological treatment tank or the second biological treatment tank is installed in parallel, the remaining first biological treatment tanks are maintained while being stopped and maintained in some of the first biological treatment tanks or the second biological treatment tanks. The operation of the organic wastewater treatment apparatus can be continued using the second biological treatment tank.

  As shown in FIG. 4, according to the present invention, the first biological treatment tank 1 and the second biological treatment tank 2 can be installed in various patterns, and the desired arrangement can be obtained according to the amount of water and the quality of raw water at the site. can do. In addition, at least one of the first biological treatment tank and the second biological treatment tank is additionally installed in parallel or in series with the existing organic wastewater treatment apparatus of the present invention structure to cope with an increase in raw water flow rate and water quality fluctuation. be able to.

  In the present invention, since the towers of the first and second biological treatment tanks 1, 2 and 41, 42 have the same shape and the same size, even when many biological treatment tanks are installed, the tower bodies are close to each other. Installed, the space between the towers can be reduced, and the installation space of the entire organic wastewater treatment apparatus can be reduced. In addition, the manufacturing cost of the tower is also low. When installing multiple towers in parallel, the structure of each tower is the same, so the installation work of the towers and the pipe connection work of each tower are the same, improving work efficiency and shortening the construction period. be able to.

  Each tower 10, 20, 50 has a diameter of 2.2 to 3.6 m, particularly 2.4 to 3.3 m, a height of 6 to 11 m, particularly 8 to 11 m, and a height H and a diameter. The ratio H / D with D is preferably 1.5 to 5.0, particularly 3.0 to 4.5. In addition, the height of the main pipe connection part, manholes 17 and 27, carrier 13, strainers 23 and 54, and diffuser pipes 12, 22, and 52 from the foundation 3 is 4 m or less, particularly 3.0 m or less. Is preferred. Thus, by providing the connecting portion, manholes 17, 27, carrier 13, strainers 23, 54, diffuser pipes 12, 22, 52, etc. at low positions, pipe connection work, equipment installation work, and various maintenance work are performed at high places. This improves work efficiency and safety.

  In this invention, you may make it install an anaerobic processing tank in the front | former stage of the 1st biological treatment tank 1 and 41, and introduce the treated water of an anaerobic treatment tank into a 1st biological treatment tank. The size of the tower body of the anaerobic treatment tank may be the same as that of the tower bodies 10 and 20 or the tower body 50.

  In this invention, you may install an adjustment tank in the front | former stage of an anaerobic or aerobic processing tank. Examples of the adjustment tank include, but are not limited to, a raw water tank for leveling the raw water flow rate, a settling tank for settling solid matter, and a pressurized flotation device.

  In the present invention, it is preferable that each biological treatment tank is preliminarily attached to a tower with attached equipment such as an air diffuser at the factory, transferred to the site, and installed on the foundation. As a result, the number of work on site can be reduced, the construction period can be shortened, and the assembly accuracy can be improved.

  In the present invention, the distance between the inlet of the raw water (treated water) and the outlet of the treated water into the biological treatment tank, that is, the distance between the upper end of the raw water introduction pipe 11 and the outlet 14a in FIGS. 5 to 8, the distance between the upper end of the raw water introduction pipe 51 and the strainer 54 (upper one) is preferably 1.5 m or more, particularly 2 m or more. By configuring in this way, the ratio of the short-circuit flow is reduced, and the COD decomposition time can be sufficiently secured.

DESCRIPTION OF SYMBOLS 1,41 1st biological treatment tank 2,42 2nd biological treatment tank 10,20,50 Tower 12,22,52 Air diffusion pipe 13 Fixed bed or rocking bed support | carrier 15,25 Atmospheric communication pipe 23,54 Strainer 29 Flow Floor carrier

Claims (3)

A device for biological treatment of organic wastewater,
It has a biological treatment tank consisting of a tower with a height of 6-11 m,
Tower body state, and are not formed integrally as a whole from the bottom to the top,
The organic wastewater biological treatment apparatus is the one before installation and construction, and the organic wastewater biological treatment apparatus is provided with attached equipment including a diffuser pipe on the tower body . Oite to claim 1, wherein the attachment device includes a pipe,
A biological treatment apparatus for organic waste water, wherein the pipe is provided on the inner peripheral surface of the tower body. 3. The biological wastewater treatment apparatus according to claim 2 , wherein the tower body is made of resin, and the top of the tower is closed except for an opening.

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