KR100683914B1 - Wastewater treatment system using sequencing batch reactors and method for wastewater treatment - Google Patents

Abstract

A sequencing batch reactor type wastewater treatment system and a sequencing batch reactor type wastewater treatment using the same are provided to improve the removal efficiency of nitrogen and phosphorous by equally flowing wastewater into the reactor through a lower part of the reactor during settling and decanting steps and maintaining the wastewater in a plug flow reactor shape, thereby proceeding denitrification and phosphorous release. A sequencing batch reactor type wastewater treatment system comprises: a retention tank(110) for providing a retention space of wastewater; a reactor(140) for providing a reaction space of wastewater; a blower(180) installed at one side of the reactor to supply oxygen into the reactor through an air supply pipe(181); a submersible aerator(150) installed in a lower part of the reactor to mix wastewater flown into the reactor and diffuse the oxygen flown in through the air supply pipe into the reactor; a wastewater distribution tank(130) installed at one side of the reactor to temporarily store wastewater supplied from the retention tank; and a wastewater distribution pipe(131) which is connected between the wastewater distribution tank and a lower part of the reactor to supply wastewater to the lower part of the reactor, wherein a plurality of pipes are branched off from one end of the wastewater distribution pipe connected to the lower part of the reactor to uniformly supply wastewater to the entire lower part of the reactor.

Description

Wastewater treatment system using Sequencing Batch Reactors and method for wastewater treatment

1 is a block diagram of a continuous batch sewage treatment apparatus according to an embodiment of the present invention.

2 is a block diagram of a treatment water discharge device.

3 is a graph showing the total nitrogen treatment efficiency.

4 is a graph showing the total phosphorus treatment efficiency.

Figure 5 is a graph showing the change in concentration of organic matter, nitrogen, phosphorus after each process, that is, mixing, aeration, precipitation, discharge process.

Figure 6 is a graph showing the concentration change of organic matter (SCOD _Cr ), nitrogen (NH ₄ -N, NO ₃ -N), phosphorus (PO ₄ -P) with time during the aeration process.

7 is a graph showing the water level of the reactor, the height of the sludge layer and the height difference between the water level and the sludge layer during the precipitation / discharge process.

8 is a graph showing the change in concentration of SCOD _Cr and NH ₄ -N, NO ₃ -N for each reaction tank at the end of discharge.

9 is a graph showing the change in nitrogen concentration according to the height of the reactor during the precipitation / discharge process.

Figure 10 is a graph showing the change in the concentration of phosphorus by the height of the reactor during the precipitation / discharge process.

11 is a graph showing the water level, dissolved oxygen, redox potential and MLSS behavior for each process.

The present invention relates to a continuous batch sewage treatment apparatus and a sewage treatment method using the same, and more particularly, in the continuous batch reaction process, a complete mixing reactor and a tubular reactor can be selectively operated to improve nitrogen and phosphorus removal efficiency. It relates to a continuous batch sewage treatment apparatus that can be, and a sewage treatment method using the same.

Sewage treatment aims at the removal of contaminants contained in sewage and is classified into primary treatment, secondary treatment and tertiary treatment according to the treatment method. Primary treatment is a method of physically removing suspended solids or sedimentary substances in the sewage system, such as gravity sedimentation and flotation, which usually includes the process from the sewage treatment plant to the initial sedimentation basin. Secondary treatment is mainly used for the treatment of organic matter dissolved in sewage and untreated organic solids in the primary treatment. Tertiary treatment is a highly advanced process that combines physical, chemical, and biological treatments to remove nutrients such as nitrogen and phosphorus in addition to low biodegradable organics that are not removed in secondary treatment.

Normally, the discharged water discharged from the sewage treatment plant has gone through the secondary treatment, and as of the end of 2003, the secondary treated water discharged from 184 domestic sewage treatment plants reaches 6.8 billion tons per year, an average of about 180 million tons per day (Ministry of Environment) Based on 2005 data). However, the secondary treated water recycled out of the discharged secondary treated water is about 158 million tons, which is only 2.4% reuse. Increasing the reuse rate of the secondary treated water to 5% has the effect of securing a dam of about 300 million tons effective capacity. Accordingly, various efforts are being made to reuse secondary treatment water in sewage treatment plants.

Reuse of secondary treated water includes washing water, sprinkling water, landscaping water, river maintenance water, agricultural water and cooling water. The treatment criteria of the tertiary treatment process in which the secondary treated water is reused are somewhat different depending on the use. For example, when used as sprinkling water or landscaping water, no chromatic treatment is required, while for washing water the chromaticity should not exceed 20 degrees.

On the other hand, as a method of performing the tertiary treatment process, there are advanced oxidation method, flocculation precipitation method, rapid filtration method, activated carbon adsorption method, continuous batch reaction method, chlorine treatment method, reverse osmosis method, membrane separation method and the like. In the western United States, where there are many cases of reuse of secondary treatment water in sewage treatment plant, it is filtered by coagulation sedimentation or filtration to remove turbidity and suspension of secondary treatment water and to enhance the disinfection and oxidation effect. Many methods have been applied. However, in case of flocculation, there is a disadvantage in that additional sludge occurs, and in the case of filtration, it is difficult to cope with clogging due to algae growth in a secondary sedimentation tank in a high temperature summer. In particular, domestic sewage treatment plants are treated with high sewage treatment as of 2003, and the discharged water is about 17%, and there is a problem that clogging of the filtration device due to scum, micro flocs, and algae growth is difficult when skilled man is lacking. have.

In case of disinfecting the secondary treated water with chlorine, disinfection by-products such as tri halo methane (THM: tri halo methane) are generated to contaminate the water source. Therefore, even chlorine disinfection equipment installed in the sewage treatment plant is not used. Is the reality. In addition, in the case of selecting a disinfection method by chlorine treatment, there is a disadvantage that a countermeasure should be taken by installing a dechlorination facility that can solve the THM problem.

Sequencing Batch Reactor (SBR) is a process that performs a series of operations such as sewage inflow, reaction, sedimentation and discharge of treated water according to a certain time schedule. It has the flexibility to change configuration and time and does not require secondary settling and sludge conveying facilities over traditional activated sludge processes. However, there is a disadvantage in that the settling and discharging period is long and the reaction does not proceed during this period, so that the residence time is longer than that of the continuous process such as activated sludge process.

The present invention has been made to solve the above problems, in the continuous batch reaction process, waste water is introduced evenly through the bottom of the reactor during the precipitation and discharge step to maintain the tubular flow reactor form to denitrification and It is an object of the present invention to provide a continuous batch sewage treatment apparatus and a sewage treatment method using the same that can improve the removal efficiency of nitrogen and phosphorus by allowing the phosphorus release reaction to proceed.

Continuous batch sewage treatment apparatus according to the present invention for achieving the above object is a storage tank for providing a storage space of waste water, a reaction tank for providing a reaction space of waste water, and provided on one side of the reaction tank through the air supply pipe inside the reactor A blower serving to supply oxygen to the reactor, an underwater stirrer provided under the reactor to mix wastewater introduced into the reactor, and to diffuse oxygen introduced through the air supply pipe into the reactor, and one side of the reactor A waste water distribution tank provided in the storage tank for temporarily storing waste water supplied from the storage tank and connected between the waste water distribution tank and a lower portion of the reaction tank to supply waste water to the lower portion of the reaction tank, and one end connected to the lower portion of the reaction tank is branched into a plurality; Evenly distributed throughout the reactor bottom front It characterized in that it comprises a waste water distribution pipe for supplying water.

Continuous batch sewage treatment method according to the present invention comprises a reaction tank for providing the storage and reaction space of the waste water, is provided with an agitator and waste water distribution pipe in the lower portion of the reaction vessel and the treatment water discharge device in the upper portion of the reactor In the sewage treatment method using a continuous batch sewage treatment device provided, waste water is introduced into the reaction tank through the lower portion of the reaction tank, the waste water is mixed by the water stirrer and the waste water mixed by the water stirrer The aeration step in which oxygen is supplied through the lower portion of the reaction tank to proceed with the aeration process, and a precipitation step of precipitating sludge in the reaction tank by stopping the operation of the oxygen in the reaction tank and stopping the operation of the underwater agitator, and the treated water. Purifying water located in the upper part of the sludge because the discharge device is lowered It comprises a discharge step of discharging to the outside of the reactor, the waste water is introduced through the lower portion of the reaction tank during the mixing, aeration, precipitation and discharge step, in the mixing and aeration step is in the form of a fully mixed flow reactor, the precipitation And in the discharge step, a tubular flow reactor.

Preferably, a waste water supply tank is provided at one side of the reaction tank, a waste water distribution pipe is provided between the waste water distribution tank and a lower portion of the reaction tank, and the waste water distribution pipe connected to the lower portion of the reaction tank is branched into a plurality of, Waste water is supplied uniformly over the entire bottom of the reactor.

According to a feature of the invention, in the process of continuous batch sewage treatment, the mixing and aeration process proceeds in the form of a Completely Mixed Flow Reactor (CMFR), and the precipitation and discharge process is a tubular flow reactor (PFR, Plug) In the form of a flow reactor, the denitrification and phosphorus release reactions can be performed to improve the efficiency of nitrogen and phosphorus removal.

Hereinafter, a continuous batch sewage treatment apparatus and a sewage treatment method using the same according to an embodiment of the present invention will be described in detail with reference to the drawings. 1 is a block diagram of a continuous batch sewage treatment apparatus according to an embodiment of the present invention.

First, as shown in FIG. 1, the continuous batch sewage treatment apparatus according to the present invention is composed of a combination of a storage tank 110 and a reaction tank 140. The storage tank 110 is a space for storing waste water, and the reaction tank 140 is a space in which a series of continuous batch reaction processes such as mixing, aeration, precipitation, and discharge are received by receiving the waste water from the storage tank 110. Through the continuous batch reaction process, the biological oxygen demand (BOD) is lowered and the nitrification and the excessive intake reaction of phosphorus proceed, which will be described in detail in the sewage treatment method described below.

Waste water supply from the storage tank 110 to the reaction tank 140 is possible through the waste water supply pump 120, and the waste water discharged through the waste water supply pump 120 is directly supplied to the reaction tank 140 before the waste water. It is stored in the wastewater distribution tank 130 through the supply pipe 121. The wastewater distribution tank 130 may be provided at one side of the upper end of the reaction tank 140. Waste water in the waste water distribution tank 130 is supplied into the reaction tank 140 through the waste water distribution pipe 131, one end of the waste water distribution pipe 131 is connected to the lower portion of the waste water distribution tank 130 and the other end It is connected to the lower portion of the reaction tank 140 has a structure in which waste water is supplied only through the lower portion of the reaction tank 140. Here, the wastewater distribution pipe 131 connected to the lower portion of the reaction tank 140 may be branched into a plurality.

Meanwhile, a submersible aerator 150 is provided at a lower portion of the reaction tank 140, and an air supply pipe 181 is provided at a lower portion of the reaction tank 140 corresponding to a position where the submersible agitator 150 is provided. The oxygen is supplied into the reactor 140 through the air supply pipe 181. The underwater stirrer 150 serves to mix the wastewater supplied into the reaction tank 140 through the wastewater distribution pipe 131 and to diffuse oxygen supplied along the air supply pipe 181 into the reaction tank 140. Perform. On the other hand, the air supply pipe 181 is one end is connected to the blower 180 provided on one side of the reactor 140 receives oxygen from the blower 180.

The treatment water discharge device 160 is provided on the reaction tank 140. The treatment water discharge device 160 serves to discharge the purified water separated from the sludge to the outside of the reaction tank 140, the treatment water discharge device 160 is a patent application filed by the present applicant in one embodiment The treatment water discharge device of the continuous batch reactor described in No. 2005-41102 can be used (see Fig. 2, reference 1: reactor). Referring to the previously applied patent, the scum formed on the surface of the reaction tank 140 and the sludge under the purified water are not discharged when the purified water is discharged through the treated water discharge device 160.

A discharge pipe 171 is provided at a lower end of the treated water discharge device 160 and one end of the discharge pipe 171 is connected to the purified water discharge water tank 170 so that the purified water is discharged to the outside of the reaction tank. For reference, the treated water discharge device 160 may be selectively moved by the drive means provided on one side of the reaction tank 140.

The operation of the continuous batch sewage treatment apparatus having such a configuration, that is, the sewage treatment method using the continuous batch sewage treatment apparatus according to the present invention will be described. The sewage treatment method using the continuous batch sewage treatment apparatus according to the present invention comprises a four-step process such as mixing, aeration, settling, and decanting, as described above. Each process will be described sequentially.

The mixing process is a process in which wastewater is supplied and mixed in the reactor 140. In detail, first, the wastewater stored in the storage tank 110 is supplied to the wastewater distribution tank 130 through the wastewater supply pump 120 and the wastewater supply pipe 121. Subsequently, the wastewater stored in the wastewater distribution tank 130 is supplied into the reaction tank 140 along the wastewater distribution pipe 131. At this time, as described above, one end of the wastewater distribution pipe 131 is connected to the lower portion of the reaction tank 140, so that the wastewater supplied through the wastewater distribution pipe 131 is disposed at the lower portion of the reaction tank 140. It is fed towards the top. In addition, one end of the wastewater distribution pipe 131 may be configured to be divided into a plurality of forms may be uniformly supplied over the entire lower surface of the reactor 140.

On the other hand, while the waste water is supplied through the waste water distribution pipe 131 at the same time, the underwater agitator 150 provided in the lower portion of the reactor 140 is operated. Accordingly, full-scale mixing of the waste water proceeds into the reactor 140. Due to the progress of the mixing process, the denitrification reaction in the waste water proceeds.

When oxygen is supplied into the reactor 140 while the mixing process is performed through the operation of the underwater stirrer 150, the aeration process is started. Here, the oxygen is supplied to the lower portion of the reaction tank 140 along the air supply pipe 181. As oxygen is supplied into the reactor 140, biological oxygen demand (BOD) of wastewater is lowered, and nitrification reaction and excess intake reaction of phosphorus proceed. As a result, the organic nitrogen in the waste water is changed to nitrate nitrogen. Before this aeration process is completed, the sludge in the reactor 140 is discharged to the outside using the sludge drawing pump.

After the aeration process, a precipitation process is performed. The precipitation process is performed by shutting off the supply of oxygen to the reactor 140 and stopping the operation of the underwater agitator 150. As the operation of the underwater stirrer 150 is stopped, sludge in the waste water is settled under the reaction tank 140 and the sludge is filtered waste water, that is, purified water is located at the top of the sludge. The sludge and the purified water separated in this way means that the discharge preparation is completed.

On the other hand, waste water is supplied from the waste water distribution tank 130 to the reaction tank 140 through the waste water distribution pipe 131 while the precipitation process is in progress. Waste water supplied into the reaction tank 140 during the precipitation process is reacted with the microorganisms in the reaction tank 140 to proceed with denitrification and phosphorus release. As the waste water is supplied in advance during the settling process and reacts with the microorganisms in the reaction tank 140 in the state where the aeration process is completed, the reaction time of the waste water is shortened when the abandonment process of the next cycle proceeds. It becomes possible. For reference, the waste water supply into the reaction tank 140 after the completion of the aeration process is equally applied in the discharge process described later as well as the precipitation process.

In the state where the precipitation process is completed as described above, the discharge process is performed. Specifically, the treatment water discharge device 160 located at the upper end of the reaction tank 140 is moved downwards to an appropriate position. As described above, the treatment water discharge device 160 may be moved by a driving means provided at one side of the reaction tank 140, and the movement distance of the treatment water discharge device 160 may be the size of the reaction tank 140 and purified water. Can be appropriately set in consideration of the height and the like. In this state, when the purified water is discharged to the outside along the treated water discharge device 160 and the discharge pipe 171, the discharge process is completed. At this time, wastewater is introduced into the reaction tank 140 even during the discharge process as described above. Since the discharge rate is larger than the inflow rate of the waste water, the water level in the reaction tank 140 is lowered, thereby lowering the bottom water level (BWL). When the water level is lowered to the position and the discharge ends, the treated water discharge device 160 is raised and the level of the reactor 140 is also raised to the top water level (TWL).

In the above, a series of continuous batch sewage treatment methods consisting of mixing, aeration, sedimentation and discharge processes were described. The mixing, aeration, precipitation and discharge processes are one cycle and the cycle can be repeated repeatedly.

On the other hand, in general, a method in which complete mixing occurs in the reaction tank 140 as soon as waste water is introduced is called a Completely Mixed Flow Reactor (CMFR), and a method of inducing a reaction at a high concentration is a tubular flow reactor (PFR). Plug Flow Reactor) In the above-described continuous batch sewage treatment method (mixing, aeration, sedimentation, discharge), the mixing and aeration process is carried out while the wastewater is supplied into the reaction tank 140 and has both a mixing function and an acid function. As complete mixing occurs by the stirrer 150, the reaction tank 140 at this time may be referred to as a complete mixing reactor (CMFR), while the precipitation and discharge processes are performed in a state in which the underwater stirrer 150 is not operated. (140) the waste water is evenly supplied to the high concentration sludge layer through the waste water distribution pipe 131 and the reaction proceeds without dispersion in the reaction tank 140. Depending on the negative reaction tank 140 at this time it may be referred to a tubular flow reactor (PFR).

Applicant proceeded the experiment applying the continuous batch sewage treatment method according to the present invention for the continuous batch sewage treatment apparatus according to an embodiment of the present invention as described above. Experiments can examine the total nitrogen (T-N) treatment efficiency, the total phosphorus (T-P) treatment efficiency, and the process-specific material behavior. The material behavior of each process is described in detail as follows: 1) change in concentration of organic matter by process, 2) change in concentration of organic matter, nitrogen and phosphorus during aeration process, 3) sludge precipitation characteristics during precipitation and discharge process, and 4) reaction tank during discharge process. ) Changes in organic and nitrogen concentrations by height, 5) Changes in nitrogen concentration by reactor 140 during precipitation and discharge processes, 6) Changes in phosphorus concentration by height in reactors 140 during precipitation and discharge processes, 7) Water level during the process, Dissolved oxygen, redox potential, and MLSS concentration can be classified. Hereinafter, the results of each experiment will be described.

[T-N Processing Efficiency]

Referring to Table 1 and FIG. 3 below, the average TN concentration of influent wastewater (influent) flowing into the reactor 140 is 33.5 mg / L and the average TN concentration of effluent water after passing through the reactor 140 is At 8.3mg / L, TN removal efficiency was 96.1%, 52.2%, and average treatment efficiency was 74.4%. In addition, it can be seen that the treated water of T-N is maintained at 1.7 to 18.4 mg / L.

<Table 1> T-N Processing Efficiency

division Wastewater (mg / L) Purified Water (mg / L) Processing efficiency (%) T-N (average value) 17.3-67.7 (33.5) 1.7-18.4 (8.3) 52.2-96.1 (74.4)

 ※ Minimum value ~ maximum value, () is the arithmetic mean.

[T-P Processing Efficiency]

Referring to Table 2 and FIG. 4, the average TP concentration of influent is 4.12 mg / L, the average TP concentration of effluent is 0.39 mg / L, and the TP removal efficiency is 99.6% and 55.1%, respectively. The average processing efficiency is 89.9%. The reason why the TP treatment efficiency is superior to the TN treatment efficiency is that, in the case of TP, as wastewater flows into the sludge layer below the reactor 140, the removal efficiency is higher than other processes by making the most of biodegradable substances included in the influent. This can be seen as higher.

<Table 2> T-P Processing Efficiency

division Wastewater (mg / L) Purified Water (mg / L) Processing efficiency (%) T-P (average value) 1.65-8.24 (4.12) 0.02-1.72 (0.39) 55.1-99.6 (89.9)

 ※ Minimum value ~ maximum value, () is the arithmetic mean.

[Changes in Organic Substances, Nitrogen and Phosphorus by Process]

Figure 5 is a graph showing the change in concentration of organic matter, nitrogen, phosphorus after each process, that is, mixing, aeration, precipitation, discharge process. As shown in FIG. 5, the SCOD _Cr concentration of the waste water was 67.0 mg / L, the TIN was 22.0 mg / L, and the TP was 3.97 mg / L, and the SCOD after 15 minutes of mixing was performed. _Cr concentration was 26.5mg / L, TIN was 13.0mg / L, PO ₄ -P was 2.50mg / L. After 60 minutes of aeration, SCOD _Cr concentration was 12.2mg / L and TIN was 7.2 mg / L, PO ₄ -P was investigated at 0.11 mg / L. In addition, the SCOD _Cr concentration of supernatant was 4.9 mg / L, TIN was 5.1 mg / L, and PO ₄ -P was 0.14 mg / L after 40 minutes of settling. The SCOD _Cr concentration was 6.3 mg / L, TIN 4.7 mg / L, and PO ₄ -P 0.23 mg / L. The removal efficiencies of organic matter (SCOD _Cr ), nitrogen (TIN) and phosphorus (PO ₄ -P) in the purified water compared to the original waste water are 90.6%, 78.6% and 94.2%, respectively.

[Changing Concentrations of Organics, Nitrogen and Phosphorus During Aeration]

Figure 6 is a graph showing the concentration changes of organic matter (SCOD _Cr ), nitrogen (NH ₄ -N, NO ₃ -N), phosphorus (PO ₄ -P) with time during the aeration process. For reference, the SCOD _Cr of wastewater used in this experiment was 128.4 mg / L, NH ₄ -N 24.5 mg / L, and PO ₄ -P concentration of 1.38 mg / L. Referring to FIG. 6, when the wastewater was completely mixed in the reactor 140, the SCOD _Cr was 39.0 mg / L, NH ₄ -N 10.1 mg / L, and PO ₄ -P concentration of 1.25 mg / L. As the aeration was started, the oxidation and nitrification of the organic matter proceeded, and the intake of phosphorus was about 30 minutes after the initiation of the aeration, and the concentration of soluble phosphorus in the reactor 140 was maintained at almost zero.

[Sludge Sedimentation Characteristics during Sedimentation / Discharge Process]

7 is a graph showing the difference between the water level of the reactor 140, the height of the sludge layer and the height between the water level and the sludge layer during the precipitation / discharge process. As shown in FIG. 7, after the aeration is stopped in a completely mixed state during the aeration process, the sludge layer is gradually settled during the settling / decanting step. After about 40 minutes of precipitation, the difference between the water surface and the sludge layer height was about 90cm, and there was no increase of the sludge interface during the discharge process.

[Change of Organic Matter and Nitrogen Concentration by Height of Reactor (140) after Discharge Process]

8 is a graph showing the concentration change of SCOD _Cr and NH ₄ -N, NO ₃ -N for each reaction tank 140 at the end of discharge. For reference, after 45 minutes of precipitation, the height of the sludge layer was 113 cm and the height of the sludge layer at the end of discharge was 70 cm. Then, the waste water to be introduced during precipitation / discharge process is evenly distributed to the precipitated high-concentration sludge layer SCOD _Cr concentration of waste water is 138mg / L, NH ₄ -N, NO ₃ -N concentrations of each 30mg / L, 0.5mg / It was L. As shown in FIG. 8, the concentration of the organic material and the NH ₄ -N in the reaction tank 140 at a height of 50 cm was rapidly reduced at the end point of discharge.

[Change of Nitrogen Concentration by Height of Reactor (140) During Precipitation / Discharge Process]

As shown in FIG. 9, the concentration of total inorganic nitrogen (NH ₄ -N + NO ₃ -N) was 7.8 mg / L at the end of the aeration process, and the concentration of NO ₃ -N was most. In addition, after 45 minutes of precipitation, a considerable amount of nitrate nitrogen was reduced in the lower part of the reactor 140. After 45 minutes of discharge, the nitrate nitrogen was almost removed from the lower part of the reactor, and the concentration of ammonia nitrogen It was confirmed that the concentration was increased.

[Change of Phosphorus Concentration by Height of Reactor (140) During Precipitation / Discharge Process]

10 is a graph showing the change in the concentration of phosphorus by the height of the reaction tank 140 during the precipitation / discharge process. For reference, after 45 minutes of precipitation, the height of the sludge layer was 113 cm and the height of the sludge layer at the end of discharge was 70 cm. As shown in FIG. 10, the concentration of PO ₄ -P in the wastewater introduced during the precipitation / discharge process was 1.56 mg / L. After sedimentation, the release of phosphorus in the sludge layer increased to 8.69 mg / L and to 13.86 mg / L at the end of discharge. The reason why phosphorus removal efficiency is higher than that of organic matter or nitrogen is because the easily biodegradable organic matters contained in the waste water directly come into contact with the sludge layer.

[Change of Water Level, Dissolved Oxygen, Redox Potential and MLSS Concentration by Process]

11 is a graph showing the water level, dissolved oxygen, redox potential and MLSS behavior for each process. For reference, the installation position of dissolved oxygen, redox potential, and MLSS meter in the reactor 140 was installed at a height of about 2 m from the bottom of the reactor 140. As shown in FIG. 11, the water level of the reaction tank 140 continuously increases as the mixing, aeration, and precipitation processes progress, and during discharge, the discharge level is lower than the inflow amount. In the case of the dissolved oxygen in the reactor 140 was maintained near zero during the mixing process, and increased from the start of the aeration process, and sharply decreased after the end of the aeration process to remain near zero. In the redox potential, the redox potential was maintained at about -300 mV during the mixing process, then rapidly increased during the aeration process, and maintained at about -100 mV, and then rapidly decreased at the end of the aeration process. In the case of the MLSS concentration of the reactor 140, the mixing and the aeration process maintained almost constant values, there was shaking of the measured values in the precipitation process, and showed a tendency to decrease rapidly when the height of the sludge layer was lowered below the MLSS measurement height. .

Continuous batch sewage treatment apparatus and sewage treatment method using the same according to the present invention has the following effects.

In the case of continuous batch sewage treatment, the mixing and aeration process is carried out in the form of a complete mixed flow reactor (CMFR), and the precipitation and discharge processes are carried out in the form of a tubular flow reactor (PFR) to improve the efficiency of nitrogen and phosphorus removal. Will be.

In addition, as the reaction proceeds in the precipitation and discharge steps, the total hydraulic residence time can be shortened.

Claims (3)

Sewage treatment using a continuous batch sewage treatment device comprising a reaction tank for storing the waste water and a reaction space, the water stirrer and the waste water distribution pipe is provided at the bottom of the reaction tank and the treated water discharge device is provided on the reaction tank. In the method, Waste water is introduced into the reaction tank through the lower portion of the reactor, the mixing step of mixing the waste water by the water stirrer; An aeration step in which oxygen is supplied through a lower portion of the reaction tank in a state in which waste water is mixed by the underwater stirrer; A precipitation step of precipitating sludge in the reactor by shutting off the oxygen supply in the reactor and stopping the operation of the agitator in water; And And a discharge step of discharging the purified water located in the upper portion of the sludge to the outside of the reaction tank by descending the treated water discharge device. Waste water is introduced through the lower part of the reaction tank during the mixing, aeration, precipitation, and discharge steps, and in the mixing and aeration steps, the waste water is in the form of a completely mixed flow reactor, and the precipitation and discharge steps are in the form of a tubular flow reactor. Continuous batch sewage treatment method. The waste water distribution tank of claim 1, wherein a waste water distribution tank is provided at one side of the reaction tank, and a waste water distribution pipe is provided between the waste water distribution tank and a lower portion of the reaction tank, and the waste water distribution pipe connected to the lower portion of the reaction tank is divided into a plurality. And supplying waste water uniformly over the entire lower surface of the reactor. A reservoir providing a storage space for waste water; A reactor providing a reaction space for waste water; A blower provided at one side of the reactor to supply oxygen into the reactor through an air supply pipe; An underwater stirrer provided at the lower portion of the reactor to mix wastewater introduced into the reactor and to diffuse oxygen introduced through the air supply pipe into the reactor; A waste water distribution tank provided at one side of the reaction tank to temporarily store waste water supplied from the storage tank; And The wastewater distribution pipe is connected between the wastewater distribution tank and the lower part of the reaction tank to supply wastewater to the lower part of the reaction tank, and one end connected to the lower part of the reaction tank is branched into a plurality of parts to uniformly supply the wastewater over the entire front surface of the reaction tank. Continuous batch sewage treatment apparatus comprising a.

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