KR20050036505A - Sewage treatment system - Google Patents

Abstract

The present invention packages the screen tank and filtration tank for pretreatment, the bioreactor comprising the anoxic and aeration tank for this treatment, and the pocket-type adsorption filtration tank for the post-treatment in a single system body to pretreat the sewage discharged from the living system. It is possible to maximize the efficiency of the treatment process by ensuring consistent treatment in one system body from high to high processing, and microbial activator or microorganism marketed by installing microorganism activator inlet on top of the anoxic tank constituting the system By allowing the injection of microorganisms such as mixed preparations, it satisfies the allowable values of BOD and SS in the effluent (20 mg / l), and also removes nitrogen, which is the cause of eutrophication, at the same time. Is a sewage treatment system that saves more than 50% .

The present invention provides a single system body having a predetermined shape and volume; A screen tank having a predetermined volume provided on an inner side of the system body corresponding to the wastewater inlet, and provided with a screen for removing the impurities contained in the wastewater at a position adjacent to the inlet; A filtering tank having a predetermined volume provided at a position adjacent to the screen tank in the system main body and having a filter material installed therein to filter the sewage supplied from the screen tank; A flow volume adjusting tank having a predetermined volume separated by a partition at a position adjacent to the filtration tank in the system body and for adjusting a flow rate of the filthy water flowing through the filtration tank; The compartment is separated and partitioned at a position adjacent to the flow control tank in the system body, and a microbial material inlet for injecting microbial materials such as an effective microorganism (EM) is provided at the top, and an agitator rotated by a motor is installed therein. An oxygen-free tank of a predetermined volume to maintain the mixing and efficient contact of the sludge contained in the sewage; Multiple aeration chambers are provided by a multi-stage baffle plate which is separated and partitioned into a partition at an oxygen-free tank and a neighboring position in the system body, and is provided at regular intervals between the aeration chambers, and each aeration chamber has an aeration pipe for aeration. A biological carrier is installed and a predetermined volume of aeration tank (adherent microbial reactor) for intermittently aeration treatment to maintain an aerobic state (Oxic) and an anoxic state (Anoxic) with respect to the sewage flowing from the anoxic tank; A sedimentation tank having a predetermined volume separated and partitioned by a partition wall at a location adjacent to the aeration tank in the system body and allowing sludge or the like contained in the treated water aerated in the aeration tank to settle; A predetermined volume of adsorption filtration tank which is separated and partitioned by a partition at a position adjacent to the sedimentation tank in the system body, and is filled with a cartridge-type adsorption filtration material to adsorb and remove chromaticity-inducing substances remaining in the treated water supplied from the settling tank; ; And a disinfection / discharge tank of a predetermined volume provided at a position adjacent to the adsorption filtration tank in the system body to disinfect and discharge the treated water introduced from the adsorption filtration tank.

Description

Sewage Treatment System {SEWAGE TREATMENT SYSTEM}

The present invention relates to a sewage treatment system, and more particularly, a screen tank and a filtration tank for pretreatment, a bioreactor composed of an anoxic tank and an aeration tank (adherent microbial reaction tank) for the main treatment, and a pocket-type adsorption for the post treatment. The filtration tank is packaged in a single system body so that the sewage discharged from the living system can be consistently treated in one system body from pretreatment to advanced treatment, maximizing the efficiency of the treatment process, and forming the system. By installing a microbial activator inlet device, it is possible to inject microorganisms such as a microbial activity promoter or a microbial mixture material, so that the effluent can be removed while nitrogen satisfies the allowable value of BOD and SS (20mg / ℓ). On the other hand, the general aeration wastewater purification device Compared to the sewage treatment system to reduce the operating cost by more than 50%.

According to the environmental classification report, domestic sewage generated in Korea is 15,441 thousand tons per day as of the end of 2000, and is treated through 172 sewage treatment plants and 76,023 sewage purification facilities. I'm staying at.

In Korea's environmental policy, sewage treatment is planned to continuously process sewage treatment plants in urban areas where population is concentrated (plan to achieve 80% sewage treatment rate by 2005). In areas where it is difficult to collect them effectively, small sewage treatment facilities are installed individually.

Currently, 95% (94,679㎢) of the total land is located in areas other than sewage treatment areas where no sewage treatment plants are installed, and the population living in this area accounts for 27% of the population. In order to properly treat the wastewater, it is urgent to develop technology for a high efficiency small scale sewage purification plant.

Unlike large-scale sewage treatment plants, small sewage purification facilities are installed near wastewater sources, which is one of the most serious problems in sewage treatment. In addition, it is possible to reduce the maintenance cost and reduce the maintenance cost, so that the so-called on-site treatment at the generation site can prevent pollution problems caused by leakage of sewage before reaching the treatment plant.

In other words, small-scale sewage treatment facilities are advantageous in terms of overall economics, including conduit costs, compared to large-scale treatment facilities such as sewage treatment plants, and are much more competitive in terms of pollutant removal efficiency because they can treat all pollutants without leakage.

In addition, the regulations stipulate that the discharge water quality standards for small-scale sewage purification facilities will be treated below 20 mg / l for both BOD and SS.

This is a strict regulation considering that sewage treatment facilities regulate BOD and SS at 20 mg / l, except for special measures area and Jamsil submerged area.

Of course, the sewage terminal treatment facility regulates nitrogen (N) and phosphorus (P) concentrations of 60 mg / l and 8 mg / l, respectively. Considering the fact that it is discharged to a large scale, small sewage purification facilities are installed and operated at a much lower cost than sewage treatment facilities, and are required to have almost equal discharge water quality standards.

Especially, considering that the discharged water quality standards of sewage terminal treatment facilities and agricultural complex wastewater treatment facilities are 30 mg / l for BOD and SS, the discharged water quality standards of small sewage purification facilities are quite strict.

As such, small-scale sewage purification facilities can be positioned as highly economical treatment facilities in areas where sewage causes are scattered, such as rural areas, and should be so when considering the quality of discharged water as indicated in current laws and regulations.

However, the actual small sewage purification facilities are designed and constructed by small companies with poor technical or financial power, and their operation is rarely managed by professional personnel.

In addition, after construction, after-care is rarely performed through monitoring.

In particular, small sewage purification facilities are often sources of relatively high concentrations or loads of organic substances and nutrients, such as restaurants and lodgings where treatment targets are individually scattered, and are close to the source and leaked or unknown, such as in the regional sewage system. Since there is almost no inflow of water, the concentration of pollutants in the influent is much higher than that of the sewage treatment plant.

In addition, due to its characteristics, the fluctuation of daily or monthly or seasonal fluctuations in the quantity and quality of the influent is large, and it is exposed to temperature change, which is one of the important environmental factors affecting the treatment efficiency in biological treatment. Uneasy.

1 is a process chart showing a process of treating sewage using a conventional continuous aeration sewage purification apparatus.

Referring to this, the conventional sewage purification apparatus 1 is composed of a screen tank (2) and a continuous aeration tank (3), a sedimentation tank (4) and a filtering means (5), when sewage is introduced into the screen tank (2) Immediately after the back is filtered, it is introduced into the continuous aeration tank (3), after a continuous aeration treatment process, after the precipitation process, and is passed through the filtration means (5).

As such, the conventional sewage purification apparatus 1 is simply composed of a bioreactor and a sedimentation tank 4 in the form of a continuous aeration tank 3, so it is insufficient in coping with load fluctuations of pollutants, especially nitrogen. There is a serious problem that nutrients are not removed.

In Korea, the importance of the nitrogen removal technique has been added to the discharged water quality standards, including agricultural and industrial complex sewage and wastewater treatment facilities, since 1996, and the importance of the nitrogen removal technique has been increased since 2001. The development of a device for removing nutrients for the urgent situation is urgent.

The present invention is to solve such a problem, the object of the screen bath and filtration tank for pretreatment, the bioreactor consisting of an anoxic and aeration tank for the present treatment, a pocket-type adsorption filtration tank for the post-treatment single It is to provide a new sewage treatment system that can be packaged in the system main body so that the sewage discharged from the living system can be treated in a single system main body from pre-treatment to advanced treatment to maximize the efficiency of the treatment process.

Another object of the present invention is to install a microorganism activator inlet device on the anoxic tank constituting the sewage treatment system to enable the injection of microorganisms such as commercially available microbial activity promoter or microbial mixture material allowance of BOD, SS in the effluent (20mg / It is to provide a new sewage treatment system that satisfies (l) while also removing nitrogen, which is a eutrophic agent, at the same time, while reducing operating costs by more than 50% compared to the general aeration system.

In order to achieve the above object, the sewage treatment system of the present invention comprises a single system body having a predetermined shape and volume; A screen tank having a predetermined volume provided on an inner side of the system body corresponding to the wastewater inlet, and provided with a screen for removing the impurities contained in the wastewater at a position adjacent to the inlet; A filtering tank having a predetermined volume provided at a position adjacent to the screen tank in the system main body and having a filter material installed therein to filter the sewage supplied from the screen tank; A flow volume adjusting tank having a predetermined volume separated by a partition at a position adjacent to the filtration tank in the system body and for adjusting a flow rate of the filthy water flowing through the filtration tank; The compartment is separated and partitioned at a position adjacent to the flow control tank in the system body, and a microbial material inlet for injecting microbial materials such as an effective microorganism (EM) is provided at the top, and an agitator rotated by a motor is installed therein. An oxygen-free tank of a predetermined volume to maintain the mixing and efficient contact of the sludge contained in the sewage; Multiple aeration chambers are provided by a multi-stage baffle plate which is separated and partitioned into a partition at an oxygen-free tank and a neighboring position in the system body, and is provided at regular intervals between the aeration chambers, and each aeration chamber has an aeration pipe for aeration. A biological carrier is installed and a predetermined volume of aeration tank (adherent microbial reactor) for intermittently aeration treatment to maintain an aerobic state (Oxic) and an anoxic state (Anoxic) with respect to the sewage flowing from the anoxic tank; A sedimentation tank having a predetermined volume separated and partitioned by a partition wall at a location adjacent to the aeration tank in the system body and allowing sludge or the like contained in the treated water aerated in the aeration tank to settle; A predetermined volume of adsorption filtration tank which is separated and partitioned by a partition at a position adjacent to the sedimentation tank in the system body, and is filled with a cartridge-type adsorption filtration material to adsorb and remove chromaticity-inducing substances remaining in the treated water supplied from the settling tank; ; And a disinfection / discharge tank of a predetermined volume provided at a position adjacent to the adsorption filtration tank in the system body to disinfect and discharge the treated water introduced from the adsorption filtration tank.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

2 is a plan view showing a sewage treatment system according to the present invention, Figure 3 is a front sectional view showing the interior of the sewage treatment system according to the present invention.

4 is a cross-sectional view taken along the line A-A of FIG. 3, FIG. 5 is a cross-sectional view taken along the line B-B of FIG. 3, and FIG. 6 is a cross-sectional view taken along the line C-C of FIG.

Referring to this, the sewage treatment system 20 according to the present invention is a screen tank 22 and a filtration tank 23 for pretreatment of the sewage discharged from the living system into a single system body 21 and the sewage of the introduced sewage. A flow rate adjusting tank 24 for adjusting the flow rate, an oxygen-free tank 25 and an aeration tank (attached microorganism reaction tank 26) for main treatment of sewage, a settling tank 27 and an adsorption filtration tank 28 for post-treatment, and a treatment Discharge tank 29 for disinfection and discharge of water is configured in the form of a package.

The system body 21 is formed in the form of a cylinder of FRP material provided with a space portion of the droplet volume therein, the sewage inlet 30 at the position where the sewage is introduced, the discharge port 31 is installed at the position where the treated water is discharged. .

In addition, the upper part of each treatment tank provided in the interior of the system body 21 is provided with a manhole 32 for checking the interior.

In the sewage treatment system 20 of the present invention, the screen tank 22 is provided inside the system main body 21 corresponding to the sewage inlet 30, and the sewage inlet 30 is adjacent to the sewage inlet 30. A screen 33 for removing the debris is installed.

The screen 33 is formed in the form of a bar, a rod, or a fine screen.

A filtration tank 23 for filtering filthy water supplied from the screen tank 22 is provided at a position adjacent to the screen tank 22 in the system main body 21, and therein crushed stone, processed stone or plastic contact material (Media). The filter medium 34 which consists of these is provided.

In the present invention, two filtration tanks 23 are provided in the system main body 21.

The flow rate adjusting tank 24 for adjusting the flow rate of the sewage introduced through the filtration tank 23 is divided into partitions 35 at positions adjacent to the filtration tank 23 in the system main body 21.

On the other hand, the oxygen-free tank 25 is separated and partitioned by the partition wall 35 at a position adjacent to the flow rate adjusting tank 24 in the system body 21.

The upper part of the anoxic tank 25 is provided with a microbial material inlet for injecting microorganisms such as effective microorganisms (EM), the sludge is mixed from the top to the inside, and the motor to allow the microbial material to be contacted efficiently The stirrer 36 which rotates by the driving force of (M) is provided.

The aeration tank 26 having a predetermined volume is formed at a position adjacent to the anoxic tank 25 in the system main body 21.

The interior of the aeration tank 26 is divided into a plurality of aeration chambers 26a by a multi-stage baffle plate 37, and the lower part of each aeration chamber 26a is a mixture of microorganisms and oxygen supply (aeration) as an energy source of the microorganisms. While the diffuser 38 is installed, a biological carrier HBC ring (Hanging Bio Contactor Ring: 39) is installed.

In the aeration tank 26, intermittent aeration treatment is performed so that an aerobic state (Oxic) and an anoxic state (Anoxic) are alternately maintained with respect to sewage flowing from the anoxic tank 25.

At a location adjacent to the aeration tank 26 in the system main body 21, a settling tank 27 having a predetermined volume for allowing sludge and the like contained in the treated water aerated in the aeration tank 26 is separated by the partition wall 35. Compartment.

In addition, at a position adjacent to the settling tank 27 in the system main body 21, there is provided an adsorption filtration tank 28 filled with a cartridge-type adsorption filter material 40 such as activated carbon, anthracite coal or charcoal.

The adsorption filtration tank 28 serves to adsorb and remove the chromaticity-inducing substance remaining in the treated water supplied from the settling tank 27.

At a position adjacent to the adsorption filtration tank 28 in the system main body 21, a predetermined volume of disinfection and discharge tank 29 for disinfecting and discharging the treated water flowing from the adsorption filtration tank 28 is provided.

The operation of the present invention made as described above is as follows.

7 is a process chart showing a process of treating sewage using a sewage treatment system according to the present invention.

Referring to this, the sewage generated in the living system is introduced into the screen tank 22 through the sewage inlet 30 on the system main body 21, and the screen tank 22 includes a relatively large contaminant contained in the introduced sewage. It is filtered by the screen 33 installed on.

Sewage flowing into the screen tank 22 is introduced into the filtration tank 23 by the pumping action of the pump P, which is relatively by the filtration material 34 such as crushed stone or processed stone or plastic contact material installed in the filtration tank 23. Small particles and suspended matter of small size are filtered out.

The sewage filtered in the filtration tank 23 is introduced into the anoxic tank 25 via the flow adjustment tank 24, the predetermined amount of microbial agent injected through the microorganism material inlet and the filthy water introduced into the anoxic tank 25 motor ( It is contacted more efficiently while mixing by the stirrer 36 which is rotated by M) at a speed of 30 rpm.

At this time, a commercially available effective microorganism (EM) is mentioned as a representative microbial agent injected into the oxygen-free tank 25, and the appropriate injection amount is 100 ppm.

Sewage mixed with the microbial agent injected in the anoxic tank 25 is introduced into the aeration tank 26 and treated by an intermittent aeration method.

In the sewage treatment system according to the present invention, the sewage introduced into the aeration tank 26 flows in a completely mixed form by the baffle plate 37 installed in the multi-stage.

In addition, a biological carrier is installed in each aeration chamber 26a in the aeration tank 26, and the HBC ring 39 using the symbiotic action and the food chain phenomenon of various microorganisms present in nature as the biological carrier in the present invention is used. It is operated by the biofilm method used as the contact medium.

During the aeration process in the aeration tank 26, as the microorganism film attached to the H.B.C ring 39 and the sewage contact repeatedly, organic matter contained in the sewage is removed.

On the other hand, in order to remove the nitrogen by operating the diffuser 38 and aeration and non-aeration are carried out alternately to operate in an intermittent aeration method so that the aerobic state (Oxic) and anoxic state (Anoxic) is alternately maintained.

In this intermittent aeration process, the time ratio of aeration / non-aeration (min / min) is appropriately set to 30/30.

The treated water aerated in the aeration tank is introduced into the settling tank 27, and in this process, sludge precipitated at the bottom of the settling tank 27 is returned to the anaerobic tank 25, and the supernatant is absorbed into the adsorption filtration tank 28. Inflow.

The supernatant introduced into the adsorption filtration tank 28 contains a chromaticity-inducing substance such as a humic substance, and the chromaticity-inducing substance is a charcoal bed or activated carbon filled in the form of a cartridge in the adsorption filtration tank 28. Or by adsorbing to the adsorption filter material 40, such as anthracite.

The treated water passing through the adsorption filtration tank 28 as described above is introduced into the discharge tank 29 and disinfected, and then discharged to the outside of the system body 21 through the discharge port 31.

On the other hand, the principle of the nitrogen removal action by the intermittent aeration treatment in the aeration tank 26 will be described in detail as follows.

In the aeration tank 26, the nitrification reaction occurs during the aeration period, that is, the aerobic period, and the denitrification reaction occurs during the non-aeration period, that is, the anaerobic period, to remove nitrogen contained in the sewage. Is done.

The nitrification reaction is a reaction in which ammonia is converted to nitrate by nitrite as an intermediate product by biological oxidation.

The nitrification reaction is performed by Nitrosomonas and Nitrobacter, which are chemical autotrophic bacteria.

Nitrosomonas: 2 NH ₄ ⁺ + 3 O ₂ → 2NO ₂ ^- + 2H ₂ O

^{_{Nitrobacter: 2NO 2 - + O 2}} → 2NO 3 -

General ^{_{reaction: NH 4 + + 2O 2 →}} H 2 O + NO 3 - + 2H +

As can be seen from the above equation, a considerable amount of oxygen is required in the nitrification process, and about 4.5 g of oxygen is required to nitrify 1 g of NH ₄ ⁺ -N (ammonia nitrogen).

Therefore, theoretically, in order to oxidize ammonia nitrogen to nitrogen, DO concentration, which is one of the nitrification influence factors, should be maintained at 4-5 mg / l or more in the reaction tank. The general formula of energy generation and cell synthesis for nitrosomonas and nitrobacter is as follows.

Nitrosomonas: 1.00 NH ₄ ⁺ + 1.44 O ₂ + 0.0496CO ₂

_{↔ 0.01C 5 H 7 NO 2 +} 0.990NO 2 - + 0.970H 2 O + 1.99H +

Nitrobacter: 1.00NO ₂ + 0.00619 NH ₄ ⁺ + 0.031 CO ₂ + 0.0124 H ₂ O + 0.50 O ₂

↔ 0.00619C ₅ H ₇ NO ₂ + 1.00NO ₃ ⁺ + 0.00619H ⁺

Overall Nitrification:

1.00 NH ₄ ⁺ + 1.89 O ₂ + 0.0805 CO ₂ →

_{0.0161C 5 H 7 O 2 N +} 0.952H 2 O + 0.984NO 3 - + 1.98H +

The formula above assumes that the cell synthesis rates (niield values) of nitrosomonas and nitrobacter are 0.08g VSS / gNH ₄ ^-- N and 0.05g VSS / gNH ₄ ^-- N, respectively, and the chemical composition of the cells is C ₅ H ₇ NO. _It is assumed to be ₂ .

As can be seen from the above formula, hydrogen ions are generated during nitrification, and the alkalinity equivalent to 7.1 g CaCO ₃ is used to oxidize 1 g of NH ₄ ⁺ -N to prevent the pH decrease caused by H ⁺ generated during nitrification. Alkalinity is consumed.

Nitrification can occur in all aerobic biological processes operating at low organic loads, provided that the conditions are appropriate.

However, under suitable conditions, the doubling time of the nitric oxide is about 15 hours, which is relatively slower than the growth rate of 20-40 minutes of the heterotrophic bacteria that decompose organic matter.

Therefore, a prerequisite for the nitrification reaction is that it must be operated with a solid retention time (SRT) long enough to hold these slow growth nitrifying bacteria in the reactor.

Suspension growth reactors, such as activated sludge processes, operate the process at a low dilution rate, or long hydraulic residence time (HRT), to achieve this goal.

As another alternative to increase the cell residence time in the reactor, cell fixation techniques can be used.

The most widely used method of such cell immobilization technique is a biofilm method that allows bacteria to naturally adhere and grow on its surface by administering an appropriate inert carrier to which bacteria can attach.

On the other hand, biological denitrification is caused by heterotrophic bacteria that use nitrate as a hydrogen acceptor when organic matter is used as an energy source under anoxic conditions with NO _x but no dissolved oxygen.

NO ₃ ^- + substrate _{(substrate) → N 2 + CO} 2 + H 2 O + OH - + cells

As can be seen in the equation above, 1g of NO ₃ under the condition of an oxygen-free state (anoxic) ^- sikineunde denitrification to -N to form the alkalinity of 3.57㎎.

In addition, the presence of an electron donor is essential for the reduction reaction of NO ₃ ⁻ .

As an electron donor, methanol is most commonly used as an organic material. The reaction when methanol is used as the electron donor is as follows.

^{_{6NO 3 - + 2CH 3 OH →}} 6NO 2 - + 2CO 2 + 4H 2 O

^{_{6NO 2 - + 3CH 3 OH →}} 3N 2 + 3CO 2 + 3H 2 O + 6OH -

----------------------------------------

^{_{6NO 3 - + 5CH 3 OH →}} 5CO 2 + 3N 2 + 7H 2 O + 6OH -

In the above formula of NO ₃ 1㎎ / ℓ ^- in order to denitrification it is required of the -N 3.86㎎ / ℓ of methanol. However, the use of chemicals such as methanol causes the operating cost of the plant to rise.

The nitrification process and the denitrification process are fundamentally opposite processes in terms of the use of oxygen, and these two processes usually occur in separate reactors.

In addition, in the removal of carbon and nitrogen using such a multistage reactor, the injection of an external carbon source is essential for denitrification.

The injection of the external carbon source is mainly carried out by injection of methanol or the like, which not only causes the complexity of operation but also increases the operating cost.

If the simultaneous reaction of nitrification and denitrification occurs in a single reactor, these disadvantages can be overcome. The most realistic method of causing both nitrification and denitrification in a single reactor is intermittent aeration, which alternates between aerobic and anaerobic conditions where nitrification and denitrification occur in a single reactor. It is to let.

8 is a chart comparing the water quality inspection history of the inflow and outflow when the sewage treatment system using the sewage treatment system according to the present invention.

Referring to FIG. 8, it can be seen that the pollutants contained in the influent water were significantly reduced after treatment using the sewage treatment system of the present invention.

Examples for demonstrating such a result are as follows.

Example 1

In order to determine the operating conditions of the sewage treatment system according to the present invention, the aeration / non-aeration time ratio (min / min) is set to 60/0, 45/15, 30/30, 15/45 through the treatment process as shown in FIG. The synthetic wastewater having the composition shown in Table 1 below was introduced under the experimental conditions of Table 2, and the results as shown in FIG. 9 were obtained.

Table 1 Composition of Synthetic Wastewater

Composition density role Glucose, C ₆ H ₁₂ O ₆ 200mg Carbon source Sodium acetateCH ₃ COONa 260mg Carbon source (NH ₄ ) ₂ SO ₄ 235mg Nitrogen source KH ₂ PO ₄ 57mg sign CaCl _{2 ·} 2H ₂ O 50 mg Trace elements MgSO ₄ 7H ₂ O 100mg Trace elements NaCl 100mg Trace elements Tap water 1ℓ Trace elements

Table 2 Experimental Conditions

Item Existing Purification System Invention system Aeration / Non-aeration Time Ratio 60/0 min 15/45 min Reactor volume 48ℓ Hydraulic stay time (HRT) 15hrs Planting microbial mass 3,000mgMLVSS / ℓ Inflow COD Concentration 400 mg / l Inflow T-N Concentration 50 mg / l Inflow T-P Concentration 13mg / l

As shown in the graph of FIG. 9, the BOD removal efficiency was about 97%, indicating a very high removal efficiency regardless of the change in aeration / non-aeration time ratio.

However, TN removal efficiency tended to increase up to 30/30 of the aeration / non-aeration time ratio (min / min), but at 15/45, it showed lower removal efficiency than at 60/0, which is required for nitrification. Due to the lack of time, the denitrification efficiency was deteriorated due to the decrease in nitrification rate.

Similar to the T-N removal trend, T-P removal efficiency tended to increase up to 30/30 aeration / non-aeration time ratio, but decreased slightly in 15/45.

Therefore, in this embodiment, the appropriate aeration / non-aeration time ratio (min / min) is determined to be 30/30.

In the conventional sewage purification apparatus, about 70% of the operating cost occupies a power cost, of which about 90% is spent on the aeration tank air supply device. Therefore, the sewage treatment system of the present invention aims to develop a system that can obtain a high treatment efficiency even by reducing the operation time of the aeration device, so the aeration / non-aeration time even at the aeration / non-aeration time ratio 25/45 of the experiment. If a removal efficiency higher than 30/30 can be obtained, a more economical system can be achieved.

As an experiment for this purpose, the treatment efficiency was investigated while increasing the amount of EM (effective microorganism) injection into the conventional sewage purification apparatus and the sewage treatment system of the present invention under the experimental conditions as shown in Table 2.

As a result, as shown in the graph of Figure 10, the BOD removal efficiency was found that the increase of the EM injection amount in both the conventional sewage purification apparatus and the sewage treatment system of the present invention does not significantly affect the removal efficiency.

However, as can be seen in the graph of FIG. 11, the TN removal efficiency was shown to increase very slightly by about 5 to 10% in the conventional sewage purification apparatus as the EM injection amount increased, whereas the sewage treatment system of the present invention. The removal efficiency was increased by up to about 50%, and the denitrification increase effect by EM was very large in the sewage treatment system of the present invention.

At this time, when the EM injection amount of 100ppm or more is considered to be very small, the appropriate EM injection amount is determined to be 100ppm.

In the graph of FIG. 12, the T-P removal efficiency showed a tendency to increase as the amount of EM injection increased in both the conventional sewage purification apparatus and the sewage treatment system of the present invention.

In the above experimental results, the optimum operating conditions and the economic evaluation of the sewage treatment system of the present invention are shown in Table 3 below.

Table 3 Appropriate operating conditions and performance of sewage treatment system of the present invention

Proper operating condition Aeration / Non-aeration Time 15/45 min EM injection volume 100 ppm Removal efficiency BOD More than 97% T-N 80% or more T-P 30% or more Economic effect Energy cost saving effect More than 75% Operation cost saving effect 50% or more Facility cost reduction effect over 10

According to Table 3 above, when the sewage treatment system of the present invention is operated at an aeration / non-aeration time ratio of 15/45 and an EM injection amount of 100 ppm, the aeration time can be reduced to a quarter of that of a conventional sewage purification apparatus, thereby reducing power costs by about 80%. In addition, the removal of organic materials as well as the removal of TN can be expected to be about 80% or more, so the overall operating cost can be reduced by more than 50% compared to the conventional sewage purification apparatus that can process 30㎥ daily. Since the capacity of the supply system can be reduced, the facility cost is also considered to be a very economical and efficient system that can save more than 10%.

Example 2

Based on the results of Example 1, the sewage treatment system of the present invention having a daily 30m 3 treatment scale was manufactured and treated under the operating conditions shown in Table 4 below, and the results as shown in Table 5 were obtained.

Table 4 Actual operating conditions of sewage treatment system of the present invention

Operating conditions Reactor volume 20㎥ Material: FRP Effective Volume: 18.75㎥ Hydraulic Dwell Time (HRT) 15hrs - Aeration / Non-aeration Time Ratio 15 / 45min - EM injection volume 100 ppm Initial installation: 1 time / During normal operation: 1 time / 3 months

Table 5 Treatment results in actual plant operation of sewage treatment system of the present invention

Processing result Analysis item Influent Runoff Removal efficiency Remarks BOD 540.8 6.35 98.8 Effluent Standard SS 763.5 2.50 99.7 COD 267.5 9.80 96.3 - T-N 75.1 14.67 80.5 Advanced processing T-P 10.5 1.52 85.5

As shown in the treatment results of Table 5, BOD and SS, which are the standard items of current effluent purification facilities effluents, were removed by an average of about 99%, and were discharged at concentrations much lower than the standard concentrations of 20 mg / l, and TN was also 80, The removal efficiency was 5%.

The TP also showed an average removal efficiency of 85.5%, which was much higher than about 40% in Example 1, which was conducted using synthetic wastewater. Due to its large size, the sewage treatment system of the present invention removes most of the pretreatment and post-treatment filtration processes, and thus, it is considered that the treatment efficiency is relatively high.

As a result of the above experiments, the sewage treatment system of the present invention is considered to be a very economical and efficient system capable of treating not only organic substances but also nitrogen at the same time.

According to the present invention, a bioreactor consisting of an anoxic tank and an aeration tank and a pocket-type adsorption filtration for post-treatment are configured in a single system body in a package form, so that sewage discharged from the living system is pretreated to advanced. The advantage is that the efficiency of the treatment process is maximized as it can be processed consistently within the system body.

In addition, as the microorganism activating agent inlet device is installed on the upper part of the anaerobic tank constituting the system, it is possible to inject microorganisms such as commercially available microbial activity promoters or microbial mixtures, and intermittent aeration so that the sewage introduced into the aeration tank is maintained in an aerobic state and anoxic state. It can be operated in such a way that it satisfies the allowable values of BOD and SS in the effluent (20 mg / l), but also removes nitrogen, which is a eutrophic agent, at the same time.

In addition, since the aeration time can be reduced to 1/4 compared to the conventional sewage purification apparatus, the power cost can be reduced by about 80%, and the overall operating cost can be reduced by 50% or more.

1 is a process chart showing a process of treating sewage using a conventional continuous aeration type sewage purification apparatus;

2 is a plan view showing a sewage treatment system according to the present invention,

Figure 3 is a front sectional view showing the inside of the sewage treatment system according to the present invention,

4 is a cross-sectional view taken along the line A-A of FIG.

5 is a cross-sectional view taken along the line B-B of FIG.

6 is a cross-sectional view taken along the line C-C of FIG.

7 is a process chart showing a process of treating sewage using a sewage treatment system according to the present invention;

8 is a table comparing the water quality inspection history over time for influent and effluent when sewage treatment using the sewage treatment system according to the present invention,

9 is a graph comparing removal characteristics according to aeration / non-aeration time ratios in a sewage treatment system and a conventional sewage purification apparatus according to the present invention;

10 is a graph comparing the removal efficiency of BOD according to the amount of EM injection in the sewage treatment system and the conventional sewage purification apparatus according to the present invention,

11 is a graph comparing the T-N removal efficiency according to the EM injection amount in the sewage treatment system and the conventional sewage purification apparatus according to the present invention,

12 is a graph comparing the T-P removal efficiency according to the EM injection amount in the sewage treatment system according to the present invention and the conventional sewage purification apparatus.

** Description of symbols for the main parts of the drawing **

21: system main body 22: screen

23: filtration tank 24: flow rate adjustment tank

25: anoxic tank 26: aeration tank (attached microorganism reaction tank)

27: sedimentation tank 28: adsorption filtration tank

29: discharge tank.

Claims (6)

A single system body 21 having a predetermined shape and volume; It is provided on the inside of the system body corresponding to the effluent inlet, the screen tank (22) of a predetermined volume provided with a screen (Screen) for removing the impurities contained in the effluent in a position adjacent to the inlet; A filtration tank 23 having a predetermined volume provided at a position adjacent to the screen tank in the system main body and having a filter material installed therein to filter filthy water supplied from the screen tank; A flow volume adjusting tank 24 having a predetermined volume for separating and partitioning the partition wall at a position adjacent to the filtration tank in the system body and for controlling the flow rate of the effluent flowing through the filtration tank; The compartment is separated and partitioned at a position adjacent to the flow control tank in the system body, and a microbial material inlet for injecting microbial materials such as an effective microorganism (EM) is provided at the top, and an agitator rotated by a motor is installed therein. A predetermined volume of anoxic tank 25 to maintain mixing and efficient contact of sludge contained in the sewage; Multiple aeration chambers are provided by a multi-stage baffle plate which is separated and partitioned into a partition at an oxygen-free tank and a neighboring position in the system body, and is provided at regular intervals between the aeration chambers, and each aeration chamber has an aeration pipe for aeration. A biological carrier is installed, and a predetermined volume of aeration tank (attached microbial reactor: 26) for intermittently aeration treatment so that aerobic state (Oxic) and anoxic state (Anoxic) are alternately maintained with respect to sewage flowing from the anoxic tank; A sedimentation tank 27 having a predetermined volume separated and partitioned by a partition at a location adjacent to the aeration tank in the system body and allowing sludge and the like contained in the treated water aerated in the aeration tank to precipitate; A predetermined volume of adsorption filtration tank which is separated and partitioned by a partition at a position adjacent to the settling tank in the system main body and filled with a cartridge-type adsorption filtration material adsorbs and removes chromaticity-inducing substances remaining in the treated water supplied from the settling tank ( 28); And a disinfection / discharge tank (29) of a predetermined volume provided at a position adjacent to the adsorption filtration tank in the system body to disinfect and discharge the treated water flowing from the adsorption filtration tank. The method of claim 1, The filter medium provided in the filtration tank (23) is sewage treatment system, characterized in that made of any one selected from crushed stone, processed stone or plastic contact material (Media). The method of claim 1, The biological carrier installed in the aeration tank (26) is a sewage treatment system, characterized in that the H.B.C ring. The method of claim 1, The adsorption filter material installed in the form of a cartridge in the adsorption filtration tank 28 is sewage treatment system, characterized in that any one selected from charcoal, activated carbon or anthracite coal. The method of claim 1, The microbial agent injected into the oxygen-free tank 25 is any one selected from the group consisting of effective microorganisms (EM), microbial mixed solution, activated microorganisms. The method of claim 1, Sewage treatment system, characterized in that the optimum aeration / non-aeration time ratio (min / min) in the aeration tank (26) is 30/30.