JP2009178628A - Apparatus for treating anaerobic waste water - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for treating anaerobic waste water, from which the amount of the granules flowing out together with the treated water can be reduced and which is excellent in stability of the capacity for treating anaerobic waste water and exhibits high efficiency when used for treating anaerobic waste water. <P>SOLUTION: The apparatus 1 for treating anaerobic waste water is characterized in that the water to be treated is made to pass through an anaerobic sludge layer 10 comprising granules 31 as an upward flow to decompose the organic matter in the water to be treated and discharge the organic matter-decomposed water as the treated water. The anaerobic sludge layer 10 is composed of a high-concentration sludge layer 3 and a low-concentration sludge layer 4 which is arranged on the downstream side of the high-concentration sludge layer 3 and has the granule 31 concentration lower than that of the high-concentration sludge layer 3. A gas-liquid separating means 5 for collecting the gasses in the water to be treated is arranged between the high-concentration sludge layer 3 and the low-concentration sludge layer 4 and a circulation means 8 is arranged for withdrawing a part of the water to be treated in the low-concentration sludge layer 4 and supplying the withdrawn water to the uppermost-stream part of the high-concentration sludge layer 3. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an anaerobic wastewater treatment apparatus having an anaerobic sludge layer having granules, in particular, it is possible to reduce the number of granules flowing out together with the treated water, and the wastewater treatment capacity is excellent in stability and high wastewater treatment. The present invention relates to an anaerobic wastewater treatment apparatus capable of obtaining efficiency.

  Conventionally, anaerobic wastewater treatment apparatuses are known as wastewater treatment apparatuses for purifying organic industrial wastewater discharged from food processing factories, beer factories, alcohol distillation factories, paper pulp factories, and the like. As an anaerobic wastewater treatment apparatus, there is one using a UASB (Upflow Anaerobic Sludge Bed) method. In the UASB method, the concentration of anaerobic microorganisms such as methanogens is formed by forming a granular granule with excellent sedimentation by using the condensation and agglomeration function of the microorganism group itself. Can be held on a sludge bed. For this reason, in the anaerobic wastewater treatment apparatus using the UASB method, excellent wastewater treatment efficiency can be obtained.

  However, even in an anaerobic wastewater treatment apparatus using the UASB method, there is a problem that a part of the granule flows out together with the treated water. If the amount of granule flowing out with the treated water increases, the amount of granule contributing to wastewater treatment will be insufficient and the wastewater treatment capacity will be reduced. Inconvenience will be caused.

As a method for reducing the number of granules flowing out with the treated water, for example, a granule collecting device for collecting and reusing the granulated particles flowing out with the treated water has been proposed (for example, Patent Document 1 and Patent Document 2). reference).
Japanese Patent Laid-Open No. 10-249382 JP-A-7-275858

  However, in the granule recovery apparatuses of Patent Document 1 and Patent Document 2, there has been a problem that the stability of wastewater treatment efficiency and wastewater treatment capacity is insufficient.

  The present invention has been made in view of the above problems, an anaerobic wastewater treatment apparatus that can reduce the amount of granules flowing out along with the treated water, is excellent in stability of wastewater treatment capacity, and obtains high wastewater treatment efficiency. The purpose is to provide.

  The anaerobic wastewater treatment apparatus of the present invention is an anaerobic wastewater treatment apparatus that decomposes organic matter in treated water and discharges it as treated water by passing the anaerobic sludge layer having granules upward. The anaerobic sludge layer is disposed on the downstream side of the high-concentration sludge layer and the high-concentration sludge layer, and the concentration of the granules is lower than that of the high-concentration sludge layer. Between the high-concentration sludge layer and the low-concentration sludge layer, gas-liquid separation means for collecting the gas in the treated water is provided, and a part of the treated water in the low-concentration sludge layer is extracted, A circulation means for supplying to the most upstream part of the high-concentration sludge layer is provided.

In the anaerobic wastewater treatment apparatus of the present invention, the circulation device may extract a part of the treated water from the most upstream part of the low-concentration sludge layer.
Moreover, in the anaerobic wastewater treatment apparatus of this invention, the said circulation apparatus shall be equipped with the nutrient supply means which supplies nutrient salt to the said to-be-processed water extracted from the said low concentration sludge layer.

  Further, in the anaerobic wastewater treatment apparatus of the present invention, a sedimentation layer is provided on the downstream side of the low-concentration sludge layer for sedimenting the granules contained in the treated water that has passed through the low-concentration sludge layer. It can be assumed that

  Further, in the anaerobic wastewater treatment apparatus of the present invention, the gas in the treated water that has passed through the low-concentration sludge layer is collected downstream of the low-concentration sludge layer, and the treated water and the granules are collected. And a gas-solid-liquid separation means for separating them.

  In the anaerobic wastewater treatment apparatus of the present invention, the high-concentration sludge layer, the gas-liquid separation means, and the low-concentration sludge layer are arranged in order from the bottom in a bottomed cylindrical reactor main body. The treated water may be introduced from the bottom of the main body and discharged as treated water from the top of the reactor main body.

  The anaerobic wastewater treatment apparatus of the present invention is an anaerobic wastewater treatment apparatus that decomposes organic matter in treated water and discharges it as treated water by passing the anaerobic sludge layer having granules upward. The anaerobic sludge layer is disposed on the downstream side of the high-concentration sludge layer and the high-concentration sludge layer, and the concentration of the granules is lower than that of the high-concentration sludge layer. Between the high-concentration sludge layer and the low-concentration sludge layer, gas-liquid separation means for collecting the gas in the treated water is provided, and a part of the treated water in the low-concentration sludge layer is extracted, Since the circulation means for supplying to the most upstream part of the high-concentration sludge layer is provided, it is possible to reduce the granule flowing out along with the treated water, the wastewater treatment capacity is stable, and the wastewater treatment is high. Efficiency is obtained.

“First Embodiment”
Hereinafter, an embodiment of an anaerobic wastewater treatment apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram for explaining an example of the anaerobic wastewater treatment apparatus of the present invention. An anaerobic wastewater treatment apparatus 1 shown in FIG. 1 uses the UASB method and flows upward through two anaerobic sludge layers 10 having granules 31 formed in a bottomed cylindrical reactor body 2. The organic matter in the for-treatment water introduced from the bottom 2a of the reactor body 2 through the treated water supply pipe 11 is decomposed, and the treated water discharge pipe 12 is passed through the upper portion 2b of the reactor body 2. It is discharged as treated water. Therefore, in the reactor main body 2 of the anaerobic wastewater treatment apparatus 1 shown in FIG. 1, the upstream side in the flow path of the water to be treated is the lower side in FIG. 1, and the downstream side is the upper side in FIG.

As shown in FIG. 1, a high-concentration sludge layer 3, a gas-liquid separation means 5, a low-concentration sludge layer 4, a sedimentation layer 7, and a gas-solid-liquid separation means 6 are provided in this order from the bottom. Yes.
The high concentration sludge layer 3 is an anaerobic sludge layer 10 having granules 31. The granule 31 is a particulate substance composed of condensed agglomerates of anaerobic microorganisms mainly composed of methanogens, and decomposes organic substances in the water to be treated to produce biogas (gas) such as methane gas or carbon dioxide gas. 32 is generated.

  The gas-liquid separation means 5 is provided between the high-concentration sludge layer 3 and the low-concentration sludge layer 4 and collects the biogas 32 in the water to be treated generated in the high-concentration sludge layer 3. . As shown in FIG. 1, the gas-liquid separation means 5 is a gas-liquid separation in which a plurality of gable roof-shaped collecting members 51 and a biogas 32 collected by the collecting members 51 are installed on the reactor body 2. And a riser tube 23a for supplying to the means 26.

  The low-concentration sludge layer 4 is an anaerobic sludge layer 10 having granules 31 as in the high-concentration sludge layer 3. The low-concentration sludge layer 4 is arranged on the downstream side (upper side in FIG. 1) than the high-concentration sludge layer 3, and the concentration of the granules 31 is lower than that of the high-concentration sludge layer 3. The concentration of the granules 31 in the low-concentration sludge layer 4 has a concentration gradient that is highest at the bottom and low at the top due to the sedimentation of the granules 31.

  As shown in FIG. 1, the sedimentation layer 7 is provided on the downstream side of the low-concentration sludge layer 4. The sedimentation layer 7 settles the fine granules 31 in the water to be treated that have passed through the low-concentration sludge layer 4 without remaining in the low-concentration sludge layer 4, and returns the granules 31 to the low-concentration sludge layer 4. The granule 31 flowing out of the reactor main body 2 together with water is reduced.

  The gas-solid-liquid separation means 6 is provided on the downstream side (the upper side in FIG. 1) of the sedimentation layer 7. The gas-solid-liquid separation means 6 collects the biogas 32 in the water to be treated that has passed through the low-concentration sludge layer 4, separates the biogas 32 and the treated water, and separates the treated water and the granules 31. Thus, the number of granules flowing out together with the treated water to the downstream side of the gas-solid-liquid separating means 6 is reduced. As shown in FIG. 1, the gas-solid-liquid separation unit 6 supplies a plurality of gable roof-shaped collection members 61 and the biogas 32 collected by the collection member 61 to the gas-liquid separation unit 26. And a riser tube 23b. When the biogas 32 is collected by the gas-solid-liquid separation means 6, the granule 31 is collected together with the biogas 32 in the collecting member 61, and the turbulent flow caused by the biogas 32 and the upward flow velocity of the water to be treated are increased. It is weakened and the sedimentation of the granule 31 is promoted. Thereby, the gas-solid-liquid separation means 6 functions as a solid-liquid separation means for separating the treated water and the granules.

  Further, in the anaerobic wastewater treatment apparatus 1 shown in FIG. 1, a part of water to be treated is extracted from the most upstream part of the low concentration sludge layer 4 (the lowest part of the low concentration sludge layer 4 in FIG. 1). Circulating means 8 for supplying the most upstream portion of the concentration sludge layer 3 (the bottom portion 2a of the reactor main body 2 in FIG. 1) is provided. As shown in FIG. 1, the circulation device 8 is extracted from the intake pipe 14 connected to the side surface of the reactor body 2, the refeed pipe 15 connected to the bottom 2 a of the reactor body 2, and the low-concentration sludge layer 4. A MONO pump 22 for supplying the water to be treated in the intake pipe 14 to the reactor main body 2 through the resupply pipe 15 at an appropriate flow rate, and a nutrient salt supply pipe (nutrient supply means) 9 are provided. Yes.

  The nutrient salt supply pipe 9 is connected to the intake pipe 14 and supplies nutrient salt to the water to be treated in the intake pipe 14 extracted from the low-concentration sludge layer 4. The nutrient salt supplied by the nutrient salt supply pipe 9 can be determined according to the type of anaerobic microorganisms constituting the granule 31 and the quality of the water to be treated, and is not particularly limited. For example, Ca, Mg Etc. can be used.

  The treated water introduced into the reactor main body 2 via the treated water supply pipe 11 is supplied from the bottom of the storage tank 18 at an appropriate flow rate using the MONO pump 21, as shown in FIG. is there. In the storage tank 18, treated water that is organic industrial wastewater discharged from a factory or the like is supplied and stored via a wastewater supply pipe 16. In addition, as shown in FIG. 1, the treated water stored in the storage tank 18 is partly treated water as circulating water via a branch pipe 13 branched from the treated water discharge pipe 12 as necessary. While being added, nutrients are added and mixed through the initial nutrient supply pipe 17 as necessary. The nutrient salt supplied by the initial nutrient supply pipe 17 may be the same as or different from the nutrient salt supplied by the nutrient supply pipe 9, and the anaerobic microorganisms constituting the granule 31 may be different. For example, Ca, Mg, Cu, Mn, or the like can be used.

  In the anaerobic wastewater treatment apparatus 1 shown in FIG. 1, gas-liquid separation means 26 is provided on the reactor body 2. The gas-liquid separation means 26 collects the biogas 32 in the water to be treated generated in the high-concentration sludge layer 3 and the low-concentration sludge layer 4, separates it from the water to be treated, and discharges the biogas 32. As shown in FIG. 1, the gas-liquid separation means 26 includes a bottomed cylindrical main body 26 a, a gas discharge pipe 25 provided to discharge the biogas 32 from the ceiling of the main body 26 a, and a granule 31. And a downer pipe 24 for discharging the water to be treated. The downer pipe 24 extends from the bottom surface of the main body 26a of the gas-liquid separation means 26 to the bottom 2a of the reactor main body 2, and the water to be treated including the granules 31 in the main body 26a of the gas-liquid separation means 26 is treated with the water to be treated. Along with the water to be treated supplied to the bottom 2a of the reactor main body 2 via the supply pipe 11, the water can be supplied from the bottom 2a of the reactor main body 2.

In the anaerobic wastewater treatment apparatus 1 shown in FIG. 1, the water to be treated is treated as follows.
First, as shown in FIG. 1, treated water that is wastewater is supplied to a storage tank 18 through a wastewater supply pipe 16 and stored. The treated water stored in the storage tank 18 is supplied with circulating water through the branch pipe 13 as necessary, and is supplied with nutrient salts through the initial nutrient supply pipe 17 as necessary. Mixed. Thereafter, the water to be treated is supplied from the bottom of the storage tank 18 to the bottom 2 a of the reactor main body 2 through the water to be treated supply pipe 11 at an appropriate flow rate using the MONO pump 21.

  When the water to be treated is introduced into the reactor main body 2, the organic matter in the water to be treated is decomposed and the biogas 32 is generated by the granules 31 constituting the high-concentration sludge layer 3. In the high-concentration sludge layer 3, the biogas 32 in which the granules 31 are generated causes turbulent flow and upward flow velocity of the treated water in the high-concentration sludge layer 3, and the granule 31 and the organic matter in the treated water. The contact is promoted to promote the decomposition of organic substances in the water to be treated. In the high-concentration sludge layer 3, the granule 31 is grown by the granulating action (condensation and agglomeration function) of the microorganism group itself constituting the granule 31. The turbulent flow and the upward flow velocity cause the granule 31 to decompose. For this reason, in the granule 31 in which sufficient sedimentation is obtained by the granulating action in the high-concentration sludge layer 3, the treated water introduced into the reactor body 2 passes through the high-concentration sludge layer 3. However, as shown in FIG. 1, it remains in the high concentration sludge layer 3. However, the granules 31 with insufficient sedimentation reach the gas-liquid separation means 5 together with the water to be treated that has passed through the high concentration sludge layer 3.

  In the gas-liquid separation means 5, the biogas 32 generated in the high-concentration sludge layer 3 is collected by the collection member 51 and separated from the water to be treated including the granules 31. The biogas 32 collected by the collecting member 51 of the gas-liquid separating means 5 is sent to the main body 26a of the gas-liquid separating means 26 by the riser pipe 23a as shown in FIG. Further, the water to be treated containing the granule 31 that has passed through the gas-liquid separation means 5 reaches the low-concentration sludge layer 4.

  In the low-concentration sludge layer 4, the granule 31 present in the low-concentration sludge layer 4 decomposes organic matter in the water to be treated that has not been decomposed in the high-concentration sludge layer 3, and generates biogas 32. Thus, the biogas 32 is generated in the low-concentration sludge layer 4 as in the high-concentration sludge layer 3. However, since the to-be-processed water which passed the high concentration sludge layer 3 is supplied to the low concentration sludge layer 4 arrange | positioned downstream from the high concentration sludge layer 3, it is supplied to the low concentration sludge layer 4. The amount of organic matter in the water to be treated is smaller than that of the high-concentration sludge layer 3 in the water to be treated. Moreover, the concentration of the granules 31 is lower in the low concentration sludge layer 4 than in the high concentration sludge layer 3. For this reason, in the low concentration sludge layer 4, the generation of biogas 32 due to the treatment of organic matter is reduced compared to the high concentration sludge layer 3, and the turbulent flow caused by the biogas 32 and the upward flow velocity of the water to be treated are It will be weak. Further, since the low-concentration sludge layer 4 is disposed on the downstream side of the gas-liquid separation means 5, the biogas generated in the high-concentration sludge layer 3 by collecting the biogas 32 in the gas-liquid separation means 5. The turbulent flow caused by 32 and the upward flow velocity of the water to be treated are weakened.

  Further, in the low-concentration sludge layer 4, as in the high-concentration sludge layer 3, the granule 31 is grown by the granulating action (condensation agglomeration function) of the microorganism group itself constituting the granule 31. The granule 31 is decomposed by the turbulent flow of the water to be treated by the biogas 32 and the upward flow velocity. However, as described above, in the low-concentration sludge layer 4, the turbulent flow due to the biogas 32 and the upward flow velocity of the water to be treated are weaker than those in the high-concentration sludge layer 3. It can prevent the granulation effect from being hindered. Therefore, in the low concentration sludge layer 4, fine granules 31 are more likely to settle than in the high concentration sludge layer 3, and the concentration of the granules 31 in the low concentration sludge layer 4 is the granule 31. As a result of sedimentation, the bottom is the highest and the top is the lower concentration gradient. In addition, since the low concentration sludge layer 4 has a lower concentration of granules 31 than the high concentration sludge layer 3, even if the turbulent flow caused by the biogas 32 or the upward flow velocity of the water to be treated is weak, the biogas 32 The effect of accelerating the contact between the granule 31 and the organic matter in the treated water and promoting the decomposition of the organic matter in the treated water is sufficiently obtained.

  In the low-concentration sludge layer 4, a part of the water to be treated at the most upstream part is extracted by the intake pipe 14 of the circulation means 8 connected to the side surface of the reactor body 2. Since the most upstream part is the part where the concentration of granules 31 in the low concentration sludge layer 4 is the highest, the treated water extracted by the circulation means 8 is high in the granules 31 in the low concentration sludge layer 4. Contained in concentration. In addition, since the most upstream part is the part closest to the high-concentration sludge layer 3, the treated water extracted by the circulation means 8 has a fine granule with insufficient sedimentation properties that has passed through the high-concentration sludge layer 3. A lot of

  As shown in FIG. 1, the water to be treated extracted from the uppermost stream portion of the low-concentration sludge layer 4 by the intake pipe 14 is caused to flow through the intake pipe 14, and the nutrient salt is supplied by the nutrient supply pipe 9 of the circulation means 8. Added. The water to be treated and the nutrient salt are sufficiently mixed by flowing through the intake pipe 14. The effect of adding nutrient salts to the water to be treated is obtained more effectively as the number of anaerobic microorganisms contained in the water to be treated increases, and the condensation and agglomeration of anaerobic microorganisms has not progressed. As a result (in other words, the finer the granule 31 is), it can be obtained effectively. The treated water extracted from the most upstream part of the low-concentration sludge layer 4 contains fine granules 31 with insufficient sedimentation at a high concentration, so that the treated water flowing in the intake pipe 14 is For example, compared with treated water existing in the downstream part of the low-concentration sludge layer 4, treated water introduced into the reactor body 2, treated water obtained after passing through the reactor body 2, nutrient salts are added The effect by doing is acquired effectively.

  The treated water to which the nutrient salt is added by the nutrient salt supply pipe 9 is controlled to an appropriate flow rate by the Mono pump 22 and is supplied again from the bottom 2 a of the reactor body 2 through the resupply pipe 15. The bottom 2a of the reactor body 2 is the most upstream part of the high-concentration sludge layer 3, and is the part farthest from the upper part 2b of the reactor body 2 discharged as treated water. For this reason, the granules 31 contained in the treated water that has been reintroduced can sufficiently contribute to the decomposition of organic substances in the treated water. In addition, since the treated water that has been reintroduced contains a lot of fine granules 31, the organic substance decomposition and granulation action of anaerobic microorganisms in the high-concentration sludge layer 3 can be effectively exhibited. Thus, the organic matter treatment efficiency in the high concentration sludge layer 3 and the sedimentation property of the granules 31 can be improved.

Moreover, as shown in FIG. 1, the granule 31 in which sufficient sedimentation property is obtained in the low-concentration sludge layer 4 by the granulating action of the anaerobic microorganisms, even if the water to be treated passes through the low-concentration sludge layer 4. It remains in the low-concentration sludge layer 4. However, some of the granules 31 with insufficient sedimentation reach the sedimentation layer 7 together with the treated water that has passed through the low-concentration sludge layer 4.
In the sedimentation layer 7, the turbulent flow due to the biogas 32 and the upward flow velocity of the water to be treated are weaker than the low-concentration sludge layer 4, and the granules 31 are likely to settle. The granules 31 that have settled in the sedimentation layer 7 are returned to the low-concentration sludge layer 4 disposed in the lower layer of the sedimentation layer 7. Further, a part of the granule 31 with insufficient sedimentation existing in the sedimentation layer 7 reaches the gas-solid-liquid separation means 6 together with the water to be treated that has passed through the sedimentation layer 7.

  In the gas-solid-liquid separation means 6, the biogas 32 in the for-treatment water that has passed through the low-concentration sludge layer 4 and the sedimentation layer 7 is collected by the collecting member 61 and separated from the for-treatment water including the granules 31. The biogas 32 collected by the collection member 61 of the gas-solid-liquid separation means 6 is sent to the main body 26a of the gas-liquid separation means 26 by the riser pipe 23b as shown in FIG. Furthermore, in the gas-solid-liquid separation means 6, the granule 31 is collected together with the biogas 32 by the collection of the biogas 32, and the turbulent flow due to the biogas 32 and the upward flow velocity of the water to be treated are collected. Is weakened and the sedimentation of the granules 31 is promoted. Thereby, the granule 31 and the water to be treated are separated.

  The treated water separated from the granules 31 by passing through the gas-solid-liquid separating means 6 is discharged as treated water from the upper part 2b of the reactor body 2 through the treated water discharge pipe 12, as shown in FIG. The A part of the discharged treated water is supplied to the storage tank 18 as circulating water via the branch pipe 13 as necessary.

  As shown in FIG. 1, in the gas-liquid separation means 26, the biogas 32 supplied from the gas-liquid separation means 5 and the gas-solid-liquid separation means 6 by the riser tubes 23a and 23b is collected in the main body 26a. . In addition, to-be-processed water containing the granule 31 that has flowed into the riser pipe 23 a together with the biogas 32 is supplied to the main body 26 a of the gas-liquid separation means 26 through the riser pipe 23 a by the upward flow of the biogas 32. . The biogas 32 collected in the main body 26 a of the gas-liquid separation means 26 is discharged from the gas discharge pipe 25. Further, the water to be treated including the granule 31 that has flowed into the main body 26 a of the gas-liquid separation means 26 is supplied from the bottom 2 a of the reactor main body 2 through the downer pipe 24 and the water to be treated supply pipe 11.

  The anaerobic wastewater treatment apparatus 1 of the present embodiment decomposes organic matter in the water to be treated and discharges it as treated water by passing the anaerobic sludge layer 10 having the granules 31 in an upward flow. The anaerobic sludge layer 10 includes a high-concentration sludge layer 3 and a low-concentration sludge layer 4 in which the concentration of granules 31 is lower than that of the high-concentration sludge layer 3. The gas-liquid separation means 5 is provided between the high-concentration sludge layer 3 and the low-concentration sludge layer 4, and a part of the treated water in the low-concentration sludge layer 4 is extracted to the uppermost stream of the high-concentration sludge layer 3. Since the circulation means 8 to be supplied to the section is provided, as shown below, the granule 31 flowing out together with the treated water can be reduced, the wastewater treatment capacity is excellent in stability, and high wastewater treatment efficiency is obtained. It is done.

  That is, in the anaerobic wastewater treatment apparatus 1 of the present embodiment, part of the water to be treated in the low concentration sludge layer 4 is supplied to the most upstream part of the high concentration sludge layer 3 by the circulation means 8. In the present embodiment, the low-concentration sludge layer 4 is disposed on the downstream side of the high-concentration sludge layer 3, so that the low-concentration sludge layer 4 has no sedimentation property that has passed through the high-concentration sludge layer 3. Many sufficiently fine granules 31 are contained. Since the fine granule 31 exhibits an excellent granulation action in the high-concentration sludge layer 3 through the circulation device, it can remain in the high-concentration sludge layer 3. Thus, according to the anaerobic wastewater treatment apparatus 1 of the present embodiment, the granules 31 of the low-concentration sludge layer 4 are reduced, and the granules 31 flowing out with the treated water through the low-concentration sludge layer 4 are discharged. While reducing, the sedimentation property of the granule 31 in the high concentration sludge layer 3 can be improved, and the granule 31 flowing out from the high concentration sludge layer 3 to the low concentration sludge layer 4 together with the treated water can be reduced.

  Moreover, the anaerobic wastewater treatment apparatus 1 of this embodiment can reduce the granule 31 which flows out with treated water in a space-saving compared with the case where the granule collection | recovery apparatus provided with a filtration means etc. is provided.

  Moreover, in the anaerobic wastewater treatment apparatus 1 of this embodiment, the fine granule 31 supplied to the uppermost stream part of the high concentration sludge layer 3 by the circulation means 8 is excellent in the granulation action in the high concentration sludge layer 3. As a result, an excellent ability to decompose organic substances can be obtained. Thereby, for example, in the anaerobic wastewater treatment apparatus 1 of this embodiment, compared with the anaerobic wastewater treatment apparatus which remove | excluded the circulation means 8 from the anaerobic wastewater treatment apparatus 1 shown in FIG. Wastewater treatment efficiency can be obtained.

  Further, the amount of granules 31 flowing out from the high-concentration sludge layer 3 to the low-concentration sludge layer 4 together with the treated water varies depending on the change in the amount of organic matter contained in the treated water. For example, the amount of organic matter contained in the water to be treated increases, and a large amount of biogas 32 is generated in the high-concentration sludge layer 3, which is decomposed by the turbulent flow of the water to be treated by the biogas 32 and the upward flow velocity. When the amount of the granule 31 increases and the granulation action of the granule 31 becomes insufficient, a large amount of the granule 31 may flow from the high-concentration sludge layer 3 to the low-concentration sludge layer 4. .

  On the other hand, in the anaerobic wastewater treatment apparatus 1 of this embodiment, even if many granules 31 flow out from the high concentration sludge layer 3 to the low concentration sludge layer 4, the water to be treated in the low concentration sludge layer 4. Since a part is supplied to the most upstream part of the high-concentration sludge layer 3 by the circulation means 8, the granule 31 flowing out from the reactor main body 2 together with the treated water can be reduced. Moreover, in the anaerobic wastewater treatment apparatus 1 of this embodiment, many granules 31 flow out from the high-concentration sludge layer 3 to the low-concentration sludge layer 4, and the granule 31 concentration of the high-concentration sludge layer 3 becomes low. Even if the organic matter in the treated water is not sufficiently decomposed in the high concentration sludge layer 3, the organic matter in the treated water remaining without being decomposed in the high concentration sludge layer 3 is decomposed in the low concentration sludge layer 4. Therefore, the anaerobic wastewater treatment apparatus 1 of the present embodiment has little fluctuation in treatment capacity due to a change in the amount of organic matter contained in the water to be treated, and is excellent in stability of wastewater treatment capacity.

  Moreover, in the anaerobic wastewater treatment apparatus 1 of this embodiment, since the circulation device 8 extracts a part of to-be-treated water from the most upstream part of the low concentration sludge layer 4, From the portion where the concentration of the granule 31 is the highest, the water to be treated containing a large amount of fine granules 31 with insufficient sedimentation properties that have passed through the high concentration sludge layer 3 can be extracted. Therefore, the settling property of the granules 31 in the high-concentration sludge layer 3 obtained by supplying the treated water in the low-concentration sludge layer 4 to the high-concentration sludge layer 3 is improved, and the granule that flows out together with the treated water. The effect of improving the decomposition ability of organic substances while reducing the amount of the slurry 31, the effect of reducing the granule 31 of the low-concentration sludge layer 4, and the effect of improving the stability of the wastewater treatment capacity can be obtained more effectively.

  Moreover, in the anaerobic wastewater treatment apparatus 1 of this embodiment, since the circulation apparatus 8 is provided with the nutrient supply means 9 which supplies nutrient salt to the to-be-processed water extracted from the low concentration sludge layer 4, it is low. The granulating action of granule 31 contained in the water to be treated extracted from the concentrated sludge layer 4 and supplied to the high-concentration sludge layer 3 and the ability to decompose organic substances can be effectively improved.

  Moreover, in the anaerobic wastewater treatment apparatus 1 of this embodiment, the sedimentation layer for sedimenting the granule 31 contained in the to-be-processed water which passed the low concentration sludge layer 4 in the downstream of the low concentration sludge layer 4 is provided. Since it is provided, it is possible to further reduce the granule 31 flowing out together with the treated water.

  In the anaerobic wastewater treatment apparatus 1 of the present embodiment, the biogas 32 in the treated water that has passed through the low-concentration sludge layer 4 is collected on the downstream side of the low-concentration sludge layer 4, and the treated water and the granule are collected. Since the gas-solid-liquid separation means 6 for separating the slurry 31 is provided, the biogas 32 can be efficiently recovered and the number of granules 31 flowing out with the treated water can be further reduced.

  Moreover, the anaerobic wastewater treatment apparatus 1 of the present embodiment is provided with a high-concentration sludge layer 3, a gas-liquid separation means 5, and a low-concentration sludge layer 4 in order from the bottom in a bottomed cylindrical reactor body 2. Since the water to be treated introduced from the bottom 2a of the reactor body 2 is discharged as treated water from the upper part 2b of the reactor body 2, the space 31 is small, and there are few granules 31 flowing out together with the treated water, and the wastewater treatment capacity The wastewater treatment efficiency is high and the biogas 32 can be efficiently recovered.

In addition, the anaerobic waste water treatment apparatus of this invention is not limited to embodiment mentioned above. For example, in the above-described embodiment, the anaerobic wastewater treatment apparatus 1 having one reactor body 2 has been described as an example. However, the anaerobic wastewater treatment apparatus of the present invention includes two reactors. May be.
As an anaerobic wastewater treatment apparatus including two reactors, for example, a high-concentration sludge layer and gas-liquid separation means are provided in a bottomed cylindrical first reactor main body, and a bottomed cylindrical second reactor main body is provided. A low-concentration sludge layer is provided therein, and water to be treated is introduced from the bottom of the first reactor main body, passes through the first reactor main body, is discharged from the top of the first reactor main body, and is discharged from the first reactor main body. The water to be treated can be introduced from the bottom of the second reactor main body, passed through the second reactor main body, and discharged as treated water from the top of the second reactor main body.

In the above-described embodiment, the circulation device 8 has been described by taking as an example an anaerobic wastewater treatment device that extracts a part of the water to be treated from the most upstream part of the low-concentration sludge layer 4. The treated water to be extracted may be a part of the treated water in the low-concentration sludge layer, and may not be from the most upstream part of the low-concentration sludge layer 4.
Moreover, although it is preferable that a circulation apparatus is provided with a nutrient supply means, it does not need to be provided with a nutrient supply means.
In the above-described embodiment, an anaerobic wastewater treatment apparatus in which a sedimentation layer is provided on the downstream side of the low-concentration sludge layer is described as an example, but the sedimentation layer may not be provided.
In the above-described embodiment, the anaerobic wastewater treatment apparatus in which the gas-solid liquid separation means is provided on the downstream side of the low-concentration sludge layer is described as an example. However, the gas-solid liquid separation means is provided. It does not have to be.

    In the above-described embodiment, the intake pipe 14 of the circulation device 8 is connected to the side surface of the reactor main body 2. However, a part of the water to be treated can be extracted from the low-concentration sludge layer. The shape of the intake pipe and the connection position with the reactor main body 2 are not particularly limited. For example, the circulation device may be provided with a water intake pipe having a water intake extending to the central portion of the low-concentration sludge layer, and the water to be treated may be extracted from the central portion of the low-concentration sludge layer. Good. In this case, the density unevenness of the granules in the low-concentration sludge layer resulting from the extraction of the water to be treated by the circulation device is small, which is preferable.

FIG. 1 is a schematic configuration diagram for explaining an example of the anaerobic wastewater treatment apparatus of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Anaerobic waste water treatment apparatus, 2 ... Reactor main body, 2a ... Bottom part, 2b ... Upper part, 3 ... High concentration sludge layer, 4 ... Low concentration sludge layer, 5, 26 ... Gas-liquid separation means, 6 ... Gas-solid-liquid separation Means 7: Sedimentation layer 8 ... Circulation means 9 ... Nutrient supply pipe (nutrient supply means) 10 ... Anaerobic sludge layer 11 ... Treated water supply pipe 12 ... Treated water discharge pipe 13 ... Branch Pipe, 14 ... Intake pipe, 15 ... Refeed pipe, 16 ... Waste water supply pipe, 17 ... Initial nutrient supply pipe, 18 ... Reservoir, 21, 22 ... Mono pump, 23a, 23b ... Riser pipe, 24 ... Downer pipe, 25 ... gas discharge pipe, 26a ... main body, 31 ... granule, 32 ... biogas, 51, 61 ... collection member.

Claims (6)

An anaerobic wastewater treatment apparatus that decomposes organic matter in treated water and discharges it as treated water by passing the anaerobic sludge layer having granules upward.
The anaerobic sludge layer is disposed on the downstream side of the high-concentration sludge layer and the low-concentration sludge layer, the concentration of the granules being lower than that of the high-concentration sludge layer. Gas-liquid separation means for collecting gas in the treated water is provided between the concentration sludge layer and the low concentration sludge layer,
An anaerobic wastewater treatment apparatus comprising a circulation means for extracting a part of the treated water from the low-concentration sludge layer and supplying it to the most upstream part of the high-concentration sludge layer.   The anaerobic wastewater treatment apparatus according to claim 1, wherein the circulation device extracts a part of the treated water from the most upstream part of the low-concentration sludge layer.   3. The anaerobic condition according to claim 1, wherein the circulation device includes a nutrient supply unit that supplies nutrients to the water to be treated extracted from the low-concentration sludge layer. Waste water treatment equipment.   The sedimentation layer for sedimenting the said granule contained in the said to-be-processed water which passed the said low concentration sludge layer is provided in the downstream of the said low concentration sludge layer, The claim 1 characterized by the above-mentioned. Item 4. The anaerobic wastewater treatment apparatus according to any one of Items 3 to 4.   A gas-solid-liquid separation means is provided on the downstream side of the low-concentration sludge layer, for collecting gas in the water to be treated that has passed through the low-concentration sludge layer, and for separating the water to be treated and the granules. The anaerobic wastewater treatment apparatus according to any one of claims 1 to 4, wherein the anaerobic wastewater treatment apparatus is provided. In the bottomed cylindrical reactor body, the high-concentration sludge layer, the gas-liquid separation means, and the low-concentration sludge layer are arranged in order from the bottom,
The anaerobic wastewater according to any one of claims 1 to 5, wherein the treated water is introduced from a bottom portion of the reactor main body and discharged as treated water from an upper portion of the reactor main body. Processing equipment.

Images