KR20030089261A - A method for removing nitrogen and phosphorus from wastewater and sewage with denitrification and nitrification rotating biological contactor - Google Patents

Abstract

PURPOSE: Provided is an advanced sewage and wastewater treatment method using a rotating biological contactor which has biological rotating discs being made of polypropylene and having smooth and planar surface, so that only strongly active microorganism can be fixed thereto and sewage and wastewater are effectively treated. CONSTITUTION: The method comprises the steps of denitrifying nitrate by introducing sewage and wastewater into an anoxic rotating biological contactor(2) in which biological rotating discs are completely submerged into water and made of polypropylene; nitrifying ammonium nitrogen by transporting the denitrified wastewater to a nitrifying rotating biological contactor(4); completely consuming DO by introducing the nitrified wastewater to an internal circulation tank(6); returning a portion of the DO-exhausted water to the anoxic rotating biological contactor(2); transporting the other portion of the DO-exhausted water to a settling tank(8) and solid-liquid separating it by adding chemicals; discharging the decant water of the settling tank(8) and returning a part of sludge to the anoxic rotating biological contactor(2); and discharging the rest of the sludge for phosphorous release thereof.

Description

Advanced process for small scale sewage and wastewater using anoxic and nitrified rotary disc reactors

The present invention relates to a method for the advanced treatment of small-scale sewage and wastewater using anoxic and nitrifying rotary disc reactors, and more particularly, the biological small-scale sewage and wastewater using a conveying line by combining a rotating disc method and an internal circulation denitrification method. It relates to a high processing method of.

The rotating disk method for wastewater treatment uses microorganisms attached to a rotating disk to alternate between water and atmosphere to transfer oxygen in the water to the water, thereby purifying contaminants through fixed microorganisms attached to the disk. As a general construction method, the operation management is easy and simple, and it is a kind of economical wastewater treatment method due to the small amount of sludge generated and low power cost due to the deposition growth process.

Korean Patent Laid-Open Publication No. 2000-0002463 discloses a microbial plate on a disc by adding 3 to 50% by weight of a bioactive ceramic to a polymer material such as polyethylene, polystyrene, polypropylene, polyvinyl chloride, etc. Efficient wastewater treatment techniques using a rotating disc method have been described, which attach rapidly and allow much better decomposition of contaminants by microorganisms.

Other prior arts related to the present invention include Korean Patent Application Nos. 193-0015753, 1997-015162, 1998-023229, and the like.

According to the prior art as described above, PVC, PE, HDPE, expanded polystyrene or the like is used as a material of the rotating disc, and the surface of the disc is formed of an uneven shape, a unit fan shape, a SARAN ROCK attachment type, or the like. That is, since the rotating disk should have a form that can quickly and easily attach a large amount of microorganisms, most of the surface is rough and the specific surface area is formed as large as possible. However, such a conventional rotational disc method not only keeps the attached microorganisms thick, but also causes nitrification, organic matter removal, and denitrification reactions to proceed in a single nitrification rotational disc reactor, resulting in temporary anaerobicization of the attached large amount of microbial layer. Desorption may occur, and centrifugal dropping of microorganisms by centrifugal force during the rotation of the disc may also occur, causing a large amount of solids to be caused in the effluent.

In addition, since the microorganisms are excessively attached to the unit disc surface, the weight per unit disc area is relatively high, and when the microorganisms are excessively attached, the rotating shaft is broken, and the attached microorganism layer is thick inactive microorganisms except for the outer surface. Because it is a layer, it is difficult for oxygen to be sufficiently diffused to the inside, so that oxygen in the atmosphere is not sufficiently transferred into the suspended sludge system during the rotation of the disc, and thus the oxygen transfer efficiency to the water is also lowered.

In Korean Patent Application No. 2001-0015262, as shown in Fig. 1, an oxygen-free oxygen, in which a motor, a speed reducer, a coupling, a bearing, and a disc monomer are held in a single axis on the same drive shaft as a rotating disc of a nitrification rotary disc reactor A technique for rotating disc reactors is disclosed. The oxygen-free rotary disc reactor adopts a method in which only 40% of the rotary disc is deposited in water to completely seal the oxygen-free rotary disc reactor with a cover. Thus, by differentiating the rotational disc deposition rate of the anoxic tank and the aerobic tank, unlike the prior art in which sludge mixing and oxygen transfer could not be simultaneously performed by a power driven from a single shaft central axis, a single motor power was used. It is possible to carry out the sludge agitation in the anoxic bath, oxygen transfer and nitrification reaction in the aerobic bath at the same time.

However, since the above technique deposits only 40% of the original plate of the anoxic rotary disc reactor in water, the residence time is long, the size of the reaction tank is increased, and the anoxic rotary disc reactor is adopted to seal the cover with the anoxic rotary disc reactor. There is difficulty. That is, when the outside air of the reaction tank flows into the oxygen-free tank, oxygen in the atmosphere is transferred to the water by the rotating disk, and the denitrification bacterium, which is a random microorganism, uses the dissolved oxygen in the water first while using the organic material as the electron donor. There is a problem that the efficiency is lowered.

In addition, Korean Patent Application No. 2001-0015263 discloses a high concentration nitrogen-containing wastewater from which a solid material has been removed through a physical treatment process, symbolic water of an internal nitrate precipitation tank, and a settling sludge returned from a denitrification precipitation tank, as shown in FIG. Introducing nitrogen into the denitrification tank and denitrifying nitrate nitrogen; Sending the mixed solution of the denitrification tank to the denitrification settling tank to separate the sludge into solid solution and sending the supernatant water to the BOD removal rotary disc reactor for returning part of the settling sludge to the denitrification tank, and discarding the rest; Flowing the supernatant of the denitrification settling tank and the final settling tank return sludge into a BOD removal rotary disc reactor to remove residual organic substances; Oxidizing the residual ammonia nitrogen by transferring the entire amount of waste water from which the residual organic material is removed to a nitrification rotary disc reactor; The ammonia nitrogen oxidized waste water is transferred to a final settling tank for solid-liquid separation, part of the supernatant water is returned to the denitrification tank and the rest is discharged, and part of the settling sludge is returned to the BOD removal rotary disc reactor and the rest is disposed of. Disclosed is a method for treating high concentration nitrogen-containing wastewater, comprising the steps of: The denitrification tank of the above technique is operated in a floating growth system, and an underwater stirrer is installed to mix the sludge. The denitrification reactor is also operated in anoxic conditions.

However, when operating an oxygen-free tank as a suspended sludge system, since a large amount of oxygen is contained in the sludge mixed liquid conveyed internally to the denitrification tank at the rear end of the nitrification tank, the denitrification bacteria are transferred to the electron acceptor. Dissolved oxygen is used instead of nitrate nitrogen, and as a result, there is a problem that the denitrification efficiency is lowered. In addition, by returning the sludge of the fixed bed system to the denitrification tank of the floating bed process at the rear end of the nitrification tank may also cause a problem of lowering the activity of the denitrification tank by the transfer of microorganisms of significantly different properties.

The present invention is to solve the above problems, by using a polypropylene (polypropylene: PP) as a rotating disc material, by treating the surface of the rotating disc flat and smooth so that only the microorganisms with a strong active adhesion thin, ㆍ To provide a method for treating sewage and wastewater more quickly and efficiently.

The present invention is also 100% deposition in order to solve the problem of the prior art that the use of separate power can not be driven at the same time when the rotary disc is 100% deposited in the oxygen-free rotary disc reactor can not drive the nitric oxide rotating disc and the denitrification tank rotating disc at the same time, By sealing the central shaft with attached discs completely and driving part is made of uniaxial type without chain, the sludge agitation and denitrification reaction of the oxygen-free rotary disc reactor and the oxygen transfer and nitrification reaction of the nitrate rotary disc reactor It is an object of the present invention to provide a method for treating sewage and wastewater, which can be performed simultaneously with a single motor power. In addition, the present invention provides a small cycle of short residence time and low maintenance cost by installing an internal circulation tank having an oxygen-free tank function at the rear end of the nitrification rotary disc reactor, so that dissolved oxygen is exhausted before being returned to the oxygen-free rotary disc reactor. It is an object of the present invention to provide a method for advanced treatment of sewage and wastewater.

1 is a view showing a nitrogen phosphorous treatment process of sewage and sewage using a rotating disc,

2 is a view showing the treatment of high concentration nitrogen-containing wastewater using a rotating disc,

3 is a view showing a reaction tank and a reaction flow used in a method for treating small-scale sewage and wastewater using an anoxic and nitrifying rotary disc reactor according to the present invention,

4 is a view showing an example in which each reaction tank used in the present invention is integrally manufactured to be movable and installed.

5 is a view showing an example of integrally manufactured so that each reaction tank used in the present invention can be buried underground.

* Explanation of symbols used in drawings

2: oxygen-free rotary disc reactor 4: nitric oxide rotary disc reactor

6: internal circulation tank 8: final settling tank

10: Chemical input device (for phosphorus removal)

12: conveying line of nitric oxide mixture from internal circulation tank to oxygen-free rotary disc reactor

14: conveying line of sludge from the final settling tank to the anaerobic rotary disc reactor

16: surplus sludge disposal line settled by chemical injection

The present invention relates to a method for the advanced treatment of small-scale sewage and wastewater using anoxic and nitrifying rotary disc reactors, and more particularly, by introducing the raw water into the anoxic rotary disc reactor (2) in which the disc is 100% deposited in water. Denitrifying nitrate nitrogen; Transferring the entire denitrified raw water to the nitrification rotary disc reactor (4) to nitrate ammonia nitrogen; Introducing the nitrified raw water into the internal circulation tank (6) to mix the dissolved oxygen (DO); A step (12) of returning a portion of the dissolved oxygen-nitriding mixture exhausted to an oxygen-free rotary disc reactor; After the internal transfer, the remainder is transferred to the final settling tank (8), the chemicals are introduced (10), separated into solid and liquid, and the supernatant flows out, and a portion of the settling sludge is returned to the anaerobic rotary disc reactor (14); After the sludge transport, the rest is related to the small scale sewage and wastewater advanced treatment method comprising the step (16) of removing the phosphorus in the excess sludge disposal.

The oxygen-free rotary disc reactor 2 used in the present invention maintains the motor, the reducer, the coupling, the bearing, and the disc monomer in a single axis on the same drive shaft as the nitrification rotary disc reactor 4. Therefore, unlike the conventional internal circulation denitrification, the sludge agitation and denitrification reaction of the oxygen-free rotary disc reactor 2 in which the rotary disc is 100% deposited in water with a single motor power driven from a single shaft center axis and The oxygen transfer and nitrification reaction of the nitrification rotary disc reactor 4 can be performed simultaneously.

In addition, the oxygen-free rotary disc reactor (2) is produced in two stages (stage), the first stage is the disc installation interval of 30 ~ 40㎜ to prevent the closing phenomenon of the disc due to the excess adhesion of microorganisms during the initial inflow of raw water inflow. It is manufactured widely and the second stage is usually manufactured by installing 10 ~ 20mm of disc installation interval according to the inflow load condition. In this way, the dissolved oxygen in the internal circulating liquid returned from the internal circulation tank 6 is reduced and maintained in a quasi-aerobic state to reduce the dissolved oxygen in the oxygen-free rotating disc reactor 2.

In addition, in the oxygen-free rotary disc reactor 2, the inflow water and the internal sludge exhausted of dissolved oxygen and the return sludge of the final settling tank 8 are introduced from the internal circulation tank 6 at the rear end of the nitric oxide rotary disc reactor 4. The introduced ammonia nitrogen is converted into nitrate nitrogen by nitrification in the nitrogen-free rotary disc reactor (2) via an oxygen-free rotary disc reactor (2) and into the anoxic rotary disc reactor at an internal circulation rate of 100 to 200%. It is returned internally. In addition, the internal transported nitric oxide mixture is discharged and removed to the atmosphere by reducing the nitrate nitrogen to nitrogen gas by the denitrification microorganism by using the organic material which is an electron donor included in the influent water as an energy source. Sewage containing recycled nitrate nitrogen is used as an oxygen source in this process. This oxygen is an element to remove BOD remaining in the secondary treatment water, and denitrification and BOD removal are performed in this process. Since the BOD introduced into the anaerobic rotary disc reactor is low in concentration, the nutrient source is supplied to complete denitrification by inputting the settling sludge returned from the final settling tank (8).

At this time, most of the microorganisms are attached to the disk and remain, and the disk is deposited 100% in water and completely sealed so that external oxygen does not enter the reactor.

In addition, the coupling portion of the oxygen-free rotary disc reactor 2 and the nitric oxide rotary disc reactor 4 is configured to be axially arranged by a bidirectional metal coupling. Such bidirectional coupling not only facilitates installation and operation of the disc coupling portion, but also facilitates maintenance. In addition, a plastic packing is inserted between the bidirectional metal couplings so that friction, wear and noise of the coupling are hardly generated between the disc coupling portions. In addition, by supporting the rotating shaft with the plastic bearing and the bearing buffer support portion, it is possible to prevent noise and corrosion, and to mitigate the impact caused by the rapid instantaneous driving of the rotating disk and the axial shaking.

The material of the rotary disc used in the oxygen-free rotary disc reactor 2 and the nitrification rotary disc reactor 4 of the present invention is polypropylene, and the surface shape is free from irregularities and bends. Accordingly, since the surface shape is free from irregularities and bends, the polypropylene rotating disc exhibits a self-cleaning function in which microorganisms to be attached are easily attached and detached, and only active microorganisms are thinly formed on the disc. Therefore, the unit load can be minimized, and the power required can be reduced by about one third compared to the existing equipment even though the motor, the reducer, the coupling, the plastic bearing, and the disc coupling are configured on a single drive shaft.

By doing this, the number of original plates can be increased and the gap can be minimized. In addition, the inert microorganisms do not attach thickly, so there is no problem of effluent solids caused by temporary microbial detachment and oxygen is rapidly delivered to the thin microbial layer formed on the surface of the disc.

In the nitrification rotary disc reactor 4, the entire amount of denitrified waste water from the oxygen-free rotary disc reactor 2 is introduced to nitrify. In the present invention, the nitrification rotary disc reactor 4 is composed of two stages. The front end is a rotary disc reactor for removing BOD to remove organic substances remaining after denitrification reaction in the oxygen-free rotary disc reactor, and the second stage is for oxidizing ammonia nitrogen to nitrate nitrogen after the remaining organic substance is oxidized. Unlike the original disc installation method as a rotary disc reactor, the number of discs is large and the interval is narrow.

In addition, unlike the oxygen-free rotary disc reactor 2, the nitrification rotary disc reactor 4 has a small amount of microorganisms attached to the disc. In other words, the heterotrophic microorganism for rapid removal of organic matter grows only in the BOD removal rotary disc reactor, which is the front end of the anoxic rotary disc reactor (2) or the nitrification rotary disc reactor (4), and thus the slow growth rate Nitric oxide rotary disc reactors predominantly nitrifying bacteria have few microorganisms in appearance. In order for the nitrifying bacteria to function normally, the dissolved oxygen acts as a limiting factor in addition to the temperature, so the dissolved oxygen concentration must be maintained high.

In addition, the rotational speed of the rotating disk is relatively fast at 18.85m / min (circumferential speed) to maintain the contact time of the wastewater and air sufficiently, and the dissolved oxygen concentration (DO) in the nitric oxide rotating disk reactor is 2-6 mg / L. Keep it.

When the inner nitrate rotary disc reactor 4 is conveyed to the denitrification tank at the rear end, there is a problem of reducing the denitrification efficiency in the denitrification tank due to high concentration of dissolved oxygen being conveyed together with the nitrate nitrogen. The tank (6) was configured at the rear end of the nitrification rotary disc reactor (4) under suspended phase anoxic conditions so that dissolved oxygen was consumed by the microorganisms. The dissolved oxygen concentration remaining in the nitrification mixture is 2 to 6 mg / l (2 to 4 mg / l in summer, 3 to 5 mg / l in spring and 4 to 6 mg / l in winter). In this internal circulation tank, the dissolved oxygen is exhausted by endogenous respiration by operating in a floating growth system.

In the final settling tank 8, the internal circulation tank 6 is returned to the oxygen-free rotary disc reactor 2 Nitrification mixtureofThe remaining nitrified wastewater was introduced, except that the flocculant was introduced in the chemical input device 10 to settle and separated into a solid and a liquid. Subsequently, the supernatant is discharged, and the settling sludge is returned to the anoxic rotary disc reactor 2 in the range of 10 to 50% by a pump operated by a timer, and the sludge is drawn and disposed at regular intervals to remove phosphorus.

By injecting coagulant allum (Al ³⁺ ) or iron salt (Fe ³⁺ ) in the ratio of soluble PO ₄ ^3- -P in raw water at the ratio of 1: 1 in the front of the final settling tank By promoting the formation of sludge, not only can shorten the residence time but also prevent excessive phosphorus load, and in the case of small-scale treatment facilities, there is an advantage of minimizing the required site since the phosphorus removal rate is fast and the amount of sludge generated is small.

In addition, the problem of lowering the denitrification efficiency may be partially improved by minimizing the dissolved oxygen in the nitrate rotating disc reactor (4), since the dissolved oxygen in the conveying sludge cannot be used to control the amount of air as in the flotation growth process. For example, the method of linking the disk rotation speed and DO meter, the method of externally conveying the final sedimentation tank sludge to the internal circulation tank and oxidizing organic matter by biologically oxidizing organic matter using BOD in the sludge as an energy source can be adopted. have.

In addition, the apparatuses of the present invention may be installed in a container manufactured to be movable by integrally manufacturing, or may be manufactured to be buried underground (Subsoil Versions). Therefore, the installation space is minimized, so it is easy to install even in a narrow site, does not affect the aesthetic scenery of the surrounding environment, protects the devices from direct sunlight, heavy rain, etc., and reduces the reduction of treatment efficiency due to the decrease in winter temperature. .

3 is a view showing an example of each reactor and the reaction flow used in the present invention. These reactors may comprise an oxygen free rotary disc reactor (2), a nitric oxide rotary disc reactor (4), an internal circulation tank (6), a final settling tank (8) and a chemical injection device (10), as shown in FIG. have.

4 is a view showing an example in which each reaction tank used in the present invention is integrally manufactured to allow movement and installation.

5 is a view showing an example of integrally manufactured so that each reaction tank used in the present invention can be buried underground.

Hereinafter, the present invention will be described in detail through examples. These examples are for illustrative purposes only, and the present invention is not limited thereto.

Example

Example 1

As shown in Fig. 3, using an oxygen-free rotary disc reactor 2, a nitrification rotary disc reactor 4, an internal circulation tank 6, a final precipitation tank 8 and a chemical injection device 10, Treatment capacity 20 m ³ / day, pH 6.7-7.2, dissolved oxygen in nitrate rotating disc reactor, 2-6 mg / l, temperature: spring / estimated 15-20 ℃, summer 21-25 ℃, winter 8-15 ℃ In phosphorus operation, urban sewage was cleaned for about six months from July 1, 2001 to December 30, 2001.

The average concentration of raw water is 73 mg / l of biological oxygen demand (SBOD), 138 mg / l of chemical oxygen demand (COD), 60 mg / l of suspended solids (SS), 27.8 mg / l of total nitrogen (TN), 3.1 mg of total phosphorus (TP) / l.

Specific equipment specifications and operating conditions of each reactor are shown in Table 1 below.

Table 1. Equipment specifications and operating conditions of each reactor

Reactor equipment data Operating conditions Remarks Anaerobic Rotary Disc Reactor (2) 1 stage Size: 0.37mx 1.34mx 1.97m Volume: 0.5966m ^{3 Number of} disks: 5 disks Spacing: 40mm HRT: 43 minutes Disc diameter: 1.2m Rotational speed: 5rpm Nitric acid nitrogen load: 5g NO ₃ -N / ㎡day Retention time: Bioreactor (5.3 hours) Final sedimentation tank (1.5 hours) Total residence time (6.7 hours) 2-stage Size: 1.61mx 1.34mx 1.97m Volume: 1.9207m ^{3 Number of} disks: 53 disks Spacing: 18mm HRT: 138 minutes Nitric Oxide Rotary Disc Reactor (4) 1 stage Size: 1.74mx 1.34mx 2.77m Volume: 1.0189m ^{3 Number of} discs: 70 discs Spacing: 18mm Disc area: 158.34m ² HRT: 69 minutes Disc diameter: 1.2 m Rotational speed: 5 rpm Ammonia nitrogen load: 2 g NH ₄ -N / m2 · day pHH 6.7 to 6.9 DO 2 to 6 mg / l 2-stage Size: 1.74mx 1.34mx 2.77m Volume: 1.0189m ^{3 Number of} discs: 70 discs Spacing: 18mm Disc area: 158.34m ² HRT: 69 minutes Internal circulation tank (6) Size: 1.2m x 0.5m x 1.0mHRT: 45 minutes Internal transfer: 100-200% underwater stirrer (oxygen-free floating phase process) DO <3mg / lpH 6.8-7.1 Final sedimentation tank (8) Volume: 1.25 m ³ HRT: 1.5 h Sludge return: 10-50% Chemical input device (10) Chemical tank (P.E): 200L x 1SET Chemical pump (DIAPHRAGM): 0.2kw L x 60 cc / min x 15A x 1SET:

[Anoxic Rotary Disc Reactor (2)]

In order to prevent the closing of the disc due to the excessive adhesion of microorganisms during the inflow of initial inflow water, 6 plates of 40 mm are installed and installed in the first stage of anoxic rotary disc reactor. The first stage of the anaerobic rotary disc reactor reduces the dissolved oxygen in the internal circulating fluid returned from the internal circulation tank and is maintained in a quasi-aerobic state to reduce the dissolved oxygen in the anaerobic rotary disc reactor. The disc spacing of the two stages of oxygen-free rotary disc reactor is usually manufactured to 18mm according to the inflow load condition.

PH of the reactor was 7.2 ± 0.2, DO was 0.5 mg / l or less, and the redox potential (ORP) was -24 to -151 mV.

Nitric Oxide Rotary Disc Reactor (4)

The rotational speed of the rotating disk is 5rpm (circumferential speed 18.85m / min) to operate relatively fast to maintain the contact time of the waste water and air sufficiently, and the dissolved oxygen concentration (DO) in the rotating disk reactor is usually 2-6 mg / L. Keep it.

In the rotational disc method, the nitrification reaction is only progressed when the organic substance concentration is maintained at 15 mg / l or less based on BOD. In this example, DO was maintained at 2-6 mg / l, pH 6.7-6.9.

The nitrification mixture flowing into the internal circulation tank 6 from the nitrification rotary disc reactor 4 has dissolved oxygen of 2 to 6 mg / l.

[Internal circulation tank (6)]

The dissolved oxygen remaining in the nitrification mixture flowing from the nitrification rotary disc reactor 4 is exhausted. The dissolved oxygen of this reactor 6 is maintained at <3 mg / l, and pH is 6.8-7.1.

[Final settling tank (8)]

In this example, a circular settler with a hydraulic retention time of 1.5 hours was used.

[Drug injection device (10)]

In this example, a 200L chemical tank and a 0.2kw L × 60 cc / min × 15A chemical pump (DIAPHRAGM) were used. The coagulant alum (Al ³⁺ ) is injected into the final settling tank front end in a ratio of 1: 1 with respect to the concentration of soluble PO ₄ ^3- -P in the raw water through the chemical input device 10, and the final settling tank (8 After separation into solid and liquid, the supernatant was discharged. At this time, the sludge is returned to the oxygen-free rotary disc reactor in the range of 10 to 50% by a pump operated by a timer, and the sludge is drawn out and discarded periodically every 1 to 3 hours to remove phosphorus.

[Processing result]

As described above, the result of treating the municipal sewage with a treatment capacity of 20 m ³ / day according to the method of the present invention is shown in Table 2 below.

Table 2. Influent and treated water quality of this example

Item Influent Quality (mg / l) Treatment water quality (mg / l) Remarks Biological Oxygen Demand (SBOD) 73 8 or less Chemical oxygen demand (COD) 138 23 or less Suspended solids (SS) 60 7 or less Total nitrogen (TN) 27.8 8 or less Total Person (TP) 3.1 1.0 or less

Example 2

In order to compare the denitrification efficiency according to the internal circulation rate, the change of the denitrification efficiency was measured while changing the circulation flow rate to 10-50 m 3. The results are shown in Table 3.

Table 3. Denitrification Efficiency According to Internal Circulation Rate

Internal circulation rate Circulating flow rate (㎥) Denitrification Efficiency (%) Remarks 50% 10 45 100% 20 67 150% 30 78 200% 40 86 250% 50 81

Example 3

In order to compare the sewage treatment efficiency of the oxygen-free rotary disc reactor according to the present invention, which is 100% deposited in water, compared to the sewage treatment efficiency of the floating-phase anaerobic tank, which is a conventional technique, the floating-phase anoxic tank and the oxygen-free rotary disc reactor according to the present invention. After each installation and sewage treatment under the same conditions, BOD removal rate, denitrification rate and residence time were measured. Comparing the results are shown in Table 4.

Table 4. Comparison of Denitrification Rate of Floating Bed Anaerobic Tank and Oxygen-free Rotary Disk Reactor of the Present Invention

Item Floating phase anaerobic tank Anaerobic Rotary Disc Reactor Remarks BOD removal rate (%) 57 75 Denitrification Rate (%) 69 86 Residence time (hours) 3.56 2.93

Example 4

In order to compare the power required for sludge mixing and oxygen transfer in the conventional sewage and wastewater treatment methods and the treatment method according to the present invention, the power consumption of each blower and agitator is measured, and the results are shown in Table 5 below. Shown in

Table 5. Power required for sludge mixing and oxygen delivery (50 ton / day, raw water is the same)

division Anaerobic / anaerobic / aerobic system Conventional Rotating Disc Reactor Method of the invention Remarks air blower 5.25 kW 0kW 0kW - agitator 040 + 0.40 + 0.40 0.75 + 1.5 kW 0.90kW Bounce is the same Sum 6.45kW 2.20kW 0.90kW

As can be seen from the above results, by using the method according to the present invention, the sewage and wastewater can be efficiently treated within a short time when the hydraulic retention time (HRT) of the bioreactor is 5.2 hours. Compared with the treatment method due to the floating growth, the operating efficiency can be reduced to 1/3 to 1/5 while the treatment efficiency is increased.

The method according to the present invention uses polypropylene as a material for the rotating disc, and an oxygen-free rotary disc reactor in which 100% of the disc is deposited in water and a nitric oxide rotary disc reactor in which 40% is deposited in water is applied to sewage and wastewater treatment. Hydraulic retention time can be reduced. The method according to the present invention also performs sludge agitation and denitrification of the anoxic rotary disc reactor, and oxygen transfer and nitrification of the nitrification rotary disc reactor at the same time with a single motor power. Reduced administrative costs

In addition, the devices used in the method for treating sewage and wastewater according to the present invention may be installed in a container that can be manufactured as a single piece and can be manufactured so as to be buried underground. Sewage and wastewater treatment methods are easy to apply on narrow sites, do not affect the aesthetic landscape of the surrounding environment, and protect devices from direct sunlight, heavy rain, etc. Can be.

Claims (4)

Small-scale sewage and wastewater treatment method using a rotating disc comprising the following: Introducing sewage and wastewater into an anoxic rotary disc reactor in which the disc is 100% deposited in water to denitrate nitrate nitrogen; Transferring the entire denitrified raw water to a nitrification rotary disc reactor to nitrify ammonia nitrogen; Introducing the nitrified raw water into an internal circulation tank and mixing the dissolved oxygen (DO); Conveying a part of the nitric oxide mixture in which the dissolved oxygen is exhausted to an oxygen-free rotary disc reactor; After the internal transfer, the rest is transferred to the final sedimentation tank, chemicals are added to separate the solid and liquid, and the supernatant is discharged, and a part of the settling sludge is returned to the oxygen-free rotary disc reactor; And Removing the phosphorus by the remaining sludge disposal after the sludge transport. The process according to claim 1, wherein the denitrification reaction of the anoxic rotary disc reactor and the nitrification reaction of the nitrification rotary disc reactor are performed simultaneously with a single motor power. The treatment method according to claim 1 or 2, wherein the treatment method is performed by a treatment apparatus which is installed in a container which is manufactured by being integrated and movable or embedded in the basement. The method of claim 1 or 2, wherein the rotating disc of the oxygen-free rotating disc reactor or the nitric oxide rotating disc reactor is made of a polypropylene material.