JP2018167229A - Bacterial cell holding carrier for treatment of nitrogen containing microorganism wastewater, sewage treatment apparatus and method of starting up sewage treatment apparatus - Google Patents

Abstract

To provide a technique capable of inhibiting bacterial cells from peeling off from a carrier by a stimulus such as a water current applied to the carrier in a bacterial cell holding carrier used for treatment of nitrogen containing wastewater.SOLUTION: A fixed-type bacterial cell holding carrier 100 for holding bacterial cells for wastewater treatment utilizing a biological reaction and used by being immersed in a liquid, has a penetration structure 102 in which the bacterial cells can be fixed to the inner wall surface. The penetration structure penetrates the bacterial cell holding carrier in a direction traversing the bacterial cell holding carrier when the bacterial cell holding carrier is used.SELECTED DRAWING: Figure 3

Description

  The present invention relates to treatment of nitrogen-containing sewage, and specifically to denitrification treatment. In more detail, it is related with the microbial cell holding support | carrier used for a denitrification process, and a sewage treatment apparatus.

  Conventionally, the activated sludge method has been widely used as sewage treatment means in sewage treatment plants, human waste treatment plants, various septic tanks, and the like. This utilizes the fact that organic substances (and some inorganic salts) are necessary for the metabolism of microorganisms such as bacteria present in organic wastewater, and these microorganisms oxidatively decompose or absorb and separate organic substances as water pollutants. This is a method for treating sewage.

  In the above sewage treatment method, a carrier may be used for the purpose of maintaining a large amount of microorganisms. And as such a carrier, those having various shapes such as a string carrier, a net carrier, a knitted carrier, a pile carrier, and a sheet carrier are known (for example, Patent Documents 1 to 3).

  In recent years, as a technology to remove nitrogen in sewage, an anaerobic and autotrophic anammox bacterium, anammox bacteria, converts ammonia nitrogen and nitrite nitrogen in sewage into nitrogen gas by anammox reaction. Is attracting attention.

  Nitrogen removal technology by anammox reaction can reduce the cost for aeration compared to conventional methods such as nitrification denitrification, does not require a carbon source, and has a small processing tank It has the advantage that it can be converted to a small amount of sludge.

  On the other hand, anammox bacteria are difficult to grow and it is difficult to grow anammox bacteria in the treatment tank in a short time, so it is necessary to start up a sewage treatment device (equipment) that performs denitrification treatment by anammox reaction. It will take time. For this reason, a wastewater treatment apparatus that enables anammox bacteria to be held in a treatment tank at a high density in a short time has been proposed (Patent Document 4).

  In addition, if a method of pre-growing anammox bacteria on a cell-supporting carrier and transferring it is used, a predetermined processing capability is exhibited simultaneously with the start-up of the apparatus (ie, without causing a time lag). Is possible. Specifically, when starting up a new sewage treatment apparatus, anammox bacteria are acclimatized and propagated in advance in an existing culture tank prior to that, and when the apparatus is started up, It is good to move to the processing tank of new equipment. Thus, prior acclimatization, growth and transfer can also be performed by growing anammox bacteria on a cell-supporting carrier and transferring the anammox bacteria together with the carrier.

JP 2001-191090 A JP 2012-20262 A JP2013-121558A JP 2015-229131 A

By the way, anammox bacteria have a property of growing while forming a bacterial mass in a granular form (hereinafter also referred to as granulation), and therefore easily peel off from the carrier due to stimulation of its own weight, water flow, etc. There is a problem of becoming. Such characteristics of anammox bacteria are particularly problematic when transferring anammox bacteria grown on a carrier as described above. That is, there is a problem that a large flow of bacteria occurs due to the occurrence of a water flow in the vertical direction when the carrier is pulled up from the culture tank, and the addition of the dead weight of the fungus without any buoyancy.

  In view of the situation as described above, the present invention suppresses bacterial cells from being detached from the carrier due to stimulation of a water flow or the like applied to the carrier in a bacterial cell holding carrier used for treatment of nitrogen-containing wastewater. It aims at providing the technology that can be.

  In order to achieve the above object, the present invention adopts the following configuration.

  The microbial cell holding carrier according to the present invention is a fixed microbial cell holding carrier that holds microbial cells for sewage treatment using biological reactions and is used by immersing in a liquid. Has a penetrating structure that can be fixed to an inner wall surface, and the penetrating structure penetrates in a direction transverse to the cell holding carrier when the cell holding carrier is used. To do.

  Here, the “transverse direction” refers to a direction having a horizontal component. For this reason, in the penetration structure, when the microbial cell holding carrier is immersed in a liquid or after being immersed (that is, when the microbial cell holding carrier is used), 2 other than the surface which becomes the bottom surface Also included are structures that penetrate seed surfaces (i.e., side-to-side and side-to-top). Here, the “surface” includes not only a plane but also a curved surface.

  When the bacterial cell holding carrier is configured as described above, the bacterial cells are held by the inner wall of the penetrating structure, whereby the influence of disturbance can be suppressed and the bacterial cells can be stably held on the carrier. In addition, in the state where the microbial cell holding carrier is installed in the liquid, the liquid passes through the penetration structure while contacting the microbial cell, so that the liquid can be efficiently denitrified without retaining the water flow. It can be carried out. The “penetrating structure” here is not limited to a hole but includes a shape such as a groove.

  The penetrating structure may be a through-hole penetrating the cell holding carrier. With such a structure, the cross section of the penetrating structure can be made a structure in which the entire periphery is surrounded by wall surfaces. For this reason, while the area which a microbial cell adheres within this penetration structure can be expanded, it can suppress more that a disturbance is added to this fixed microbial cell. For this reason, it becomes possible to hold | maintain a microbial cell to a support | carrier more stably, and it can suppress more effectively that a microbial cell peels from a support | carrier.

  Furthermore, the through-hole may penetrate the cell holding carrier horizontally when the cell holding carrier is used. With such a configuration, when the bacterial cell holding carrier is pulled up from the liquid, the liquid can gently flow out of the through hole, and disturbance applied to the bacterial cells can be suppressed. For this reason, it becomes possible to suppress more effectively that a microbial cell peels from a support | carrier.

  In addition, the through-hole may be one that penetrates the cell support carrier obliquely when the cell support carrier is used. With such a configuration, when the bacterial cell holding carrier is pulled up from the liquid, the liquid can flow out from the through hole relatively slowly, and the bacterial cell can be prevented from peeling off. In addition, since the gas generated during the nitrogen decomposition process easily escapes upward from the penetrating structure, it is possible to prevent a reduction in processing efficiency caused by the gas staying in the penetrating structure.

The through-hole may penetrate the cell holding carrier in a V shape when the cell holding carrier is used. With such a configuration, when the bacterial cell holding carrier is pulled up from the liquid, the liquid can be prevented from flowing out of the through hole, and the bacterial cells can be prevented from being peeled off by the water flow. In addition, since the gas generated during the nitrogen decomposition process easily escapes upward from the penetrating structure, it is possible to prevent a reduction in processing efficiency caused by the gas remaining in the penetrating structure.

  The cell holding carrier may have a plurality of the penetrating structures. With such a configuration, it becomes possible to hold more bacterial cells on the bacterial cell holding carrier, and to improve the treatment efficiency of sewage.

  Further, the microbial cells held by the microbial cell holding carrier may be anammox bacteria. Since anammox bacteria have the property of growing while forming a bacterial mass in granular form, it has a feature that it is harder to adhere to the holding carrier compared to other bacteria, and the bacterial mass is easily detached from the carrier. ing. For this reason, it is possible to more effectively utilize the effect of the cell-supporting carrier according to the present invention that the cells can be stably held on the carrier against anammox bacteria.

  The sewage treatment apparatus according to the present invention is a sewage treatment apparatus in which the microbial cell holding carrier is immersed. Moreover, the sewage treatment apparatus according to the present invention may include the microbial cell holding carrier and a treatment tank in which a liquid flows in a direction orthogonal to the penetrating structure of the microbial cell holding carrier. With such a configuration, it is possible to suppress the microbial cells held in the penetration structure of the carrier from being separated by the water flow passing through the penetration structure in the treatment tank.

  The method for starting up the sewage treatment apparatus according to the present invention includes a step of immersing the microbial cell holding carrier in a culture solution to cause the microbial cell holding carrier to hold the microbial cell, and the microbial cell holding method. And a step of pulling up the cell support from the culture solution and a step of transferring the cell support picked up from the culture solution to a treatment tank for wastewater treatment.

  As in this method, by transferring the carrier in which the bacterial cells are already retained to the treatment tank, it is not necessary to wait for the bacterial cells to grow, so the construction period for starting up the sewage treatment apparatus can be shortened. Can do. In addition, it is possible to ensure the initial performance of the wastewater treatment apparatus by suppressing the microbial cells held on the carrier from being detached when the microbial cell holding carrier is moved.

  In view of the situation as described above, the present invention suppresses bacterial cells from being detached from the carrier due to stimulation of a water flow or the like applied to the carrier in a bacterial cell holding carrier used for treatment of nitrogen-containing wastewater. It is possible to provide a technology that can.

FIG. 1 is a schematic diagram illustrating an outline of the sewage treatment apparatus according to the first embodiment. FIG. 2 is a schematic diagram illustrating a configuration of a treatment tank of the sewage treatment apparatus according to the first embodiment. 3A is a perspective view of the cell holding carrier according to Example 1, FIG. 3B is a front view of the cell holding carrier according to Example 1, and FIG. 3C is a side view of the cell holding carrier according to Example 1. FIG. FIG. 4 is a schematic view showing the configuration of the reaction tank used in the experiment. FIG. 5 is a graph showing the results of the removal rate of the carrier used in the experiment and the comparative carrier. Since FIG. 6A represents the 1st modification about the inclination of the penetration structure of a microbial cell holding support | carrier, it is a figure. FIG. 6B is a diagram because it represents a second modification example regarding the inclination of the penetration structure of the bacterial cell holding carrier. FIG. 6C is a diagram illustrating a third modification example regarding the inclination of the penetration structure of the bacterial cell holding carrier. FIG. 7 is a diagram showing a first modification of the shape of the penetration structure of the cell body holding carrier. FIG. 8 is a diagram illustrating a second modification of the shape of the penetration structure of the microbial cell holding carrier. FIG. 9 is a diagram illustrating a third modification of the shape of the penetrating structure of the bacterial cell holding carrier. FIG. 10 is a diagram illustrating a modification of the base body and penetrating structure of the microbial cell holding carrier. FIG. 11 is a flowchart showing the flow of the method for starting up the sewage treatment apparatus according to the second embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be exemplarily described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified.

<Example 1>
FIG. 1 is a schematic diagram showing an outline of a sewage treatment apparatus 1 in this embodiment. As shown in FIG. 1, the sewage treatment apparatus 1 includes a treatment tank 10, an adjustment tank 20, a thermostatic tank 30, and a pH control unit 40.

  The treatment tank 10 is a tank for denitrifying the primary treated water supplied from the adjustment tank 20 described later by an anammox reaction using the microbial cell holding carrier 100 to which anammox bacteria are attached. The generated nitrogen gas is exhausted, and the final treated water after denitrification is discharged.

  The adjustment tank 20 partially oxidizes ammonia nitrogen in sewage (raw water) to be treated into nitrite nitrogen in advance, and includes primary treated water containing ammonia nitrogen and nitrite nitrogen in a predetermined ratio. It is a tank to be generated. The primary treated water is supplied from the adjustment tank 20 to the treatment tank 10 by a pump (not shown).

  The thermostat 30 is a tank that adjusts the temperature of the water to be treated in order to keep the temperature of the primary treated water (hereinafter also referred to as the water to be treated) in the treatment tank 10 constant. The temperature of the water to be treated is adjusted by circulating the water to be treated in the treatment tank 10 through a path including the thermostat 30 and the treatment tank 10.

  The pH controller 40 measures the pH of the water to be treated as needed, and appropriately adds dilute sulfuric acid in order to keep the pH of the water to be treated to be alkalized by the anammox reaction at an appropriate value (less than pH 8.0).

  FIG. 2 is a schematic diagram illustrating the configuration of the processing tank 10. As shown in FIG. 2, the treatment tank 10 includes a primary treated water supply port 11, a treated water discharge port 12, a nitrogen gas exhaust port 13, a sulfuric acid injection port 14, constant temperature bath circulation ports 15 a and 15 b, a stirring blade 16, and a plurality of The microbial cell holding carrier 100 is provided. In addition, W1 in a figure has shown the water level in the tank of to-be-processed water.

  From the primary treated water supply port 11, the above-mentioned primary treated water is supplied into the tank, and the anammox bacteria adhering to the fixed type cell holding carrier 100 fixedly installed inside the tank causes ammonia in the treated water. Nitrogen and nitrite nitrogen are decomposed into nitrogen gas and water. Then, the final treated water and nitrogen gas after denitrification are discharged from the treated water discharge port 12 and the nitrogen gas exhaust port 13, respectively. In addition, fixed installation means fixing and installing so that the microbial cell holding support | carrier 100 may not flow through to-be-processed water.

  Dilute sulfuric acid for pH adjustment by the pH control unit 40 is injected from the sulfuric acid injection port 14. Further, the water to be treated circulates through the thermostatic bath 30 through the thermostatic bath circulation ports 15a and 15b, and the temperature of the water to be treated is kept constant. Moreover, the stirring blade 16 is installed in the center of the bottom part of the processing tank 10, and the anammox bacteria adhering to the microbial cell holding support | carrier 100 and the to-be-processed water will contact evenly by stirring the to-be-processed water. And improve processing efficiency.

  In addition, if arbitrary prior art is used for each structure of the primary treated water supply port 11, the treated water discharge port 12, the nitrogen gas exhaust port 13, the sulfuric acid injection port 14, the constant temperature bath circulation ports 15a and 15b, and the stirring blade 16. Since it is good, detailed description is omitted. The same applies to a mechanism for fixing and installing a plurality of bacterial cell holding carriers 100 in the treatment tank 10.

  Next, the microbial cell holding carrier 100 in the present embodiment will be described. 3A to 3C show the microbial cell holding carrier 100 in this example, FIG. 3A is a perspective view of the microbial cell holding carrier 100, FIG. 3B is a front view of the microbial cell holding carrier 100, and FIG. 3 is a side view of the carrier 100. FIG.

  As shown in FIG. 3A, the fungus body holding carrier 100 according to the present embodiment has a structure in which a plurality of through holes 102 having a square cross section are horizontally formed in a base body 101 which is a columnar rectangular parallelepiped. The base 101 has a length in the width direction of 15 mm, a length in the depth direction of 10 mm, and a vertical length of 350 mm as viewed from the front, and is made of polyurethane. The through hole 102 is formed in a rectangular shape having a cross section of 10 mm in the bottom and 5 mm in height, and has a penetrating structure extending the length of the base 101 (10 mm). In this embodiment, thirty through holes 102 are formed in a line at equal intervals over the entire length of the base 101.

  A plurality of such cell-supporting carriers 100 are fixedly installed in the treatment tank 10, and anammox bacteria adhere to the inner wall of the through-hole 102 and grow in a granular form in the liquid to be treated. In this way, denitrification is performed by an anammox reaction when the anammox bacteria granulated on the inner wall of the through-hole 102 and the water to be treated come into contact. In addition, in order that the nitrogen gas generated at this time is discharged toward the upper part of the processing tank 10, the plurality of fungus body holding carriers 100 in the processing tank 10 do not block the opening of the through hole 102. It arrange | positions by adjusting direction and / or space | interval.

  In addition to the inner wall of the through hole 102, anammox bacteria may adhere to the surface of the base 101 and granulate. However, most of them are peeled off from the cell-supporting carrier 100 due to disturbance such as water flow in the treatment tank and their own weight, and are discharged from the treatment tank 10 together with the treated water.

  As described above, since the water to be treated enters from near the bottom of the treatment tank 10 and is discharged from near the top, even if the stirring blade 16 is not in operation, A water flow in a direction substantially orthogonal to the through hole 102 of the body holding carrier 100 is generated. For this reason, the anammox bacteria adhering to the surface of the base | substrate 101 will be directly exposed to such a water flow, and will peel easily.

  In this respect, the anammox bacteria adhering to the inner wall of the through-hole 102 are less affected by the water flow as described above. Processing efficiency can be improved. This is clear from the following experimental example.

(Experimental example)
In the present experimental example, a start-up test of a wastewater treatment reactor by an anammox reaction was performed using a fixed bed carrier in which thirty through-holes having a depth of 10 mm and a circular cross section with a diameter of 5 mm were stacked vertically. Moreover, the start-up test of the wastewater treatment reactor by an anammox reaction was performed on the same conditions using the nonwoven fabric support | carrier of 40 mm x 380 mm x 20 mm (it does not have a penetration structure), and it was set as the comparison object.

Specifically, each carrier is filled in a 3.5 L jacketed reaction tank having the structure shown in FIG. 4, water to be treated is supplied, the overflowed water is collected as treated water, and the treated water is collected. The nitrogen removal rate was calculated from the TN concentration and the residence time in the reaction vessel. The filling rate, the carrier is 19% of this experiment is 34% compared carriers (nonwoven carrier) is the surface area of the cell holding portions, the carrier of the present invention 1178Cm ^2, comparative carrier is 1216cm ^2.

  The composition of water to be treated (raw water) is 550 mg / L ammonium sulfate, 650 mg / L sodium nitrite, 500 mg / L potassium bicarbonate, 27 mg / L potassium dihydrogen phosphate, 180 mg / L calcium chloride dihydrate, magnesium sulfate 300 mg / L and trace metals 1 and 2 were adjusted to 1 ml / L, and the water temperature was adjusted to 30 ° C. The composition of the trace metal 1 is 5 g / L of EDTA and 5 g / L of iron sulfate, and the composition of the trace metal 2 is 15 g / L of EDTA, 0.43 g / L of zinc sulfate heptahydrate, and 0.03 g of cobalt chloride hexahydrate. 24 g / L, manganese chloride tetrahydrate 0.99 g / L copper sulfate pentahydrate 0.23 g / L, sodium molybdate dihydrate 0.22 g / L, nickel chloride hexahydrate 0.19 g / L L, sodium selenate decahydrate 0.21 g / L, boric acid 0.014 g / L.

  Anammox sludge (seed sludge) that had been acclimatized with the above raw water composition was added to the reaction tank so that the SS concentration was 100 mg / L. Further, the pH in the reaction vessel was controlled with 0.1N sulfuric acid so as to be less than 8.0.

FIG. 5 is a graph showing the removal rate results of the carrier of this experimental example and the comparative carrier under the above conditions. The horizontal axis represents the number of days elapsed after the addition of seed sludge, and the vertical axis represents the nitrogen removal rate. As shown in FIG. 5, the carrier of this experimental example, while the removal rate up to 4.0kg ^{/ m} 3 ^/ d is increased by 70 days, after reaching 1.5kg ^{/ m} 3 ^/ d in the comparative carrier 40 days The removal speed no longer increases.

  Such experimental results show that the anammox bacteria in this experimental example grew on the inner wall of the through-hole and formed a bacterial mass, so that peeling was suppressed, while the comparative carrier formed a bacterial mass on the surface of the carrier. , Showing repeated growth and detachment.

  As described above, according to the microbial cell holding carrier 100 and the sewage treatment apparatus 1 in the present embodiment, by holding the microbial cells on the inner wall of the through hole 102, due to disturbance such as a water flow applied to the carrier, It is possible to prevent the microbial cells from being detached from the microbial cell holding carrier 100.

<Modification>
In the above embodiment, the microbial cell holding carrier 100 has a configuration in which a plurality of through holes 102 having a rectangular cross section are formed in a rectangular parallelepiped substrate 101. The penetrating structure may be other than the above shape.

(About the inclination of the penetrating structure)
FIG. 6A to FIG. 6C are diagrams showing modified examples of the inclination of the penetrating structure of the bacterial cell holding carrier, and show views of the bacterial cell holding carrier as viewed from the side. In addition, the broken line in a figure represents the penetration structure formed in the base | substrate of a microbial cell holding support | carrier.

The penetrating structure in the cell-supporting carrier is not limited to a horizontal structure (that is, a structure having no inclination). As shown to FIG. 6A and 6B, you may penetrate the microbial cell holding support | carrier diagonally. Further, it is not always necessary to penetrate from one side surface of the carrier to the surface opposite to the side surface, and one of the openings of the through holes is formed on the upper surface of the substrate as shown in FIG. 6B. May be. By having an oblique penetration structure in this way, the treated water can flow out from the through-hole relatively slowly when the bacterial cell holding carrier is pulled up from the water, and the bacterial cell can be prevented from peeling off. In order to make such an effect remarkable, the inclination angle may be 45 degrees or less.

  Furthermore, since the penetration structure is formed in an oblique direction, the gas generated during the sewage decomposition process can easily escape upward from the penetration structure, so that the processing efficiency caused by the gas staying in the penetration structure can be improved. It is also possible to prevent the decrease.

  Moreover, as shown in FIG. 6C, the penetrating structure may be formed in a V shape when the microbial cell holding carrier is viewed from the side. With such a configuration, when the bacterial cell holding carrier is pulled up from the water, the treated water can be prevented from flowing out of the through-hole, and the bacterial cells can be prevented from being peeled off by the water flow. In addition, since the gas generated during the sewage decomposition process can easily escape upward from the penetrating structure, it is possible to prevent a reduction in processing efficiency caused by the gas staying in the penetrating structure.

(About the shape of the penetration structure)
FIG. 7 to FIG. 10 are perspective views showing modifications of the shape of the penetration structure of the microbial cell holding carrier. The shape of the penetrating structure of the microbial cell holding carrier is not limited to the through hole having a quadrangular cross section. For example, it may be a through hole having another polygonal cross section such as a triangle, or may be a through hole having a circular cross section as shown in FIG. Further, the arrangement of the through holes does not have to be in a vertical row, and may be formed in two or more vertical rows as shown in FIG. Furthermore, as shown in FIG. 8, the shape of the through hole may be a structure having a cross section other than a polygon or a circle.

However, as for the size of the through hole, it is desirable that the cross-sectional area in front view is between 20 mm ² and 400 mm ² for the following reason. That is, if the size of the through hole is too small, the through hole is buried with the granulated bacterial mass, and the bacteria attached to the wall surface in the through hole may not be used for sewage treatment. On the other hand, if the through-hole is too large, the effect of suppressing the bacteria attached to the through-hole from peeling off due to disturbance such as a water flow may be weakened.

  Moreover, the penetration structure of the microbial cell holding carrier is not limited to a structure (hole) in which the entire periphery is closed in front view (that is, a cross section in the vertical direction). For example, as shown in FIG. 9, a structure in which a part is open may be used.

  As described above, the penetrating structure of the cell-supporting carrier is not limited to a narrow shape, and can have various shapes. In particular, when sewage treatment is performed by an anammox reaction, the treated water is in an environment in which bacteria other than anammox bacteria are difficult to coexist, so there is no need to remove deposits on the carrier by aeration, etc. Even if the shape is complicated, no particular inconvenience occurs.

(About the shape and structure of the substrate)
In addition, the shape of the substrate of the microbial cell holding carrier can also be a shape other than a rectangular parallelepiped. For example, a polygonal column shape other than a rectangular parallelepiped may be used, or a cylindrical shape may be used. Moreover, it may have a stepped shape instead of such a columnar shape.

Further, the base body does not have to be an integral molded product. 10A and 10B are perspective views showing a modification of the base body (and penetrating structure) of the bacterial cell holding carrier. As shown to FIG. 10A and 10B, the base | substrate of a microbial cell holding support | carrier may be comprised by combining a some member. FIG. 10A shows a fungus body holding carrier in which a penetrating structure is formed by partitioning two plate-like members with a wave-like partition member, and FIG. 10B is a combination of two carriers of FIG. 10A. Shows things.

As described above, the shape and structure of the substrate of the bacterial cell holding carrier are not limited and can be variously modified. However, if the shape of the substrate is extremely thin, it may not be possible to form a penetrating structure having an area effective for holding bacterial cells, so that the projected area from the top of the substrate is preferably 20 mm ² or more. .

<Example 2>
Next, another embodiment according to the present invention will be described. This example is a method for starting up a sewage treatment apparatus using the bacterial cell holding carrier 100 of Example 1. After the apparatus is started up, the anammox bacteria are conditioned and grown in the treatment tank of the apparatus (hereinafter, culture In other words, the start-up process includes such culture of anammox bacteria. FIG. 11 is a flowchart showing the flow of the start-up method of the sewage treatment apparatus according to the present embodiment. As shown in FIG. 11, in this embodiment, the sewage treatment apparatus is started up by the following method.

  First, in the culture tank, the microbial cell holding carrier 100 is immersed in a culture solution suitable for acclimatization of anammox bacteria, and the anammox bacteria are attached and held on the carrier (step S101). Then, the retained anammox bacteria is conditioned in the culture solution (step S102). Thereafter, when the anammox bacteria held on the cell holding carrier 100 are sufficiently grown, the cell holding carrier 100 is pulled up from the culture solution (step S103) and transferred to the treatment tank of the sewage treatment apparatus that starts up the cell holding carrier 100 (S104). ).

  In the method for starting up the sewage treatment apparatus as described above, it is not necessary to wait for anammox bacteria to grow on the cell support carrier in the treatment tank of the newly installed sewage treatment apparatus. Such a construction period can be shortened. That is, the method for starting up the sewage treatment apparatus of the present embodiment is such that the anammox bacteria are sufficiently grown in advance in a cell holding carrier in a culture tank different from the apparatus to be started up, and this is treated as a treatment tank of a new apparatus. It is included in the start-up process that the whole cell carrier is transferred.

  And since the microbial cell holding | maintenance support | carrier 100 has a structure as stated already, when it pulls up from a culture solution in step S103, and when it is moved to a new processing tank in step S104, a water flow etc. It can suppress that the microbial cell hold | maintained by the support | carrier will peel by disturbance. For this reason, it can suppress that the anammox bacteria acclimatized and propagated in step S102 decline with a transfer operation | work, and it becomes possible to ensure the initial performance of a sewage treatment apparatus.

  In this example, the microbial cell holding carrier to be used was the same as that of Example 1. However, using various other shaped microbial cell holding carriers described in the above-described modification, steps S101 to S101 are performed. The sewage treatment apparatus may be started up by the process of S104.

<Others>
Each of the above-described embodiments is merely illustrative of the present invention, and the present invention is not limited to the specific forms described above. The present invention can be variously modified within the scope of its technical idea. For example, in each of the above-described embodiments, the material of the bacterial cell holding carrier is made of polyurethane, but the material of the carrier is not limited to this. For example, other materials such as nylon and other resins, ceramics and the like may be used as long as they can maintain the strength as a carrier even if they are placed in moisture for a long time.

DESCRIPTION OF SYMBOLS 1 ... Sewage treatment apparatus 10 ... Treatment tank 11 ... Primary treated water supply port 12 ... Treated water discharge port 13 ... Nitrogen gas exhaust port 14 ... Sulfuric acid injection port 16 ... Stirring Blade 20 ... Adjustment tank 30 ... Constant temperature bath 40 ... pH control unit 100 ... Fungus body holding carrier

Claims (7)

A fixed type cell holding carrier that holds cells for wastewater treatment using biological reactions and is immersed in a liquid,
The fungus body has a penetrating structure that can be fixed to the inner wall surface,
The penetration structure penetrates in a direction transverse to the bacterial cell holding carrier when the bacterial cell holding carrier is used.   The microbial cell holding carrier according to claim 1, wherein the penetrating structure is a through-hole penetrating the microbial cell holding carrier.   The microbial cell holding carrier according to claim 1, wherein the microbial cell holding carrier has a plurality of the penetrating structures.   The microbial cell holding carrier according to any one of claims 1 to 3, wherein the microbial cell is an anammox bacterium. The bacterial cell holding carrier according to any one of claims 1 to 4,
A treatment tank in which a liquid flows in a direction orthogonal to the penetrating structure of the bacterial cell holding carrier;
A sewage treatment apparatus comprising:   A sewage treatment apparatus in which the bacterial cell holding carrier according to any one of claims 1 to 4 is immersed. Immersing the bacterial cell holding carrier according to any one of claims 1 to 4 in a culture solution of the bacterial cell, thereby allowing the bacterial cell holding carrier to hold the bacterial cell;
A step of pulling up the bacterial cell holding carrier in which the bacterial cells are held from the culture solution;
Transferring the bacterial cell holding carrier pulled up from the culture solution to a treatment tank for sewage treatment;
A method for starting up a sewage treatment apparatus, comprising:

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