KR101018587B1 - Membrane treatment device for eliminating nitrogen and/or phosphorus - Google Patents

Abstract

PURPOSE: A membrane separation advanced treatment apparatus for removing nitrogen and phosphorus is provided to repeatedly purify the nitrogen, the phosphorus, and organic waste inside wastewater. CONSTITUTION: A membrane separation advanced treatment apparatus for removing nitrogen and phosphorus comprises the following: a flow amount controlling tank(1) receiving wastewater filtered by a screen tank(10); a microfiltration screen(11) passing through the raw water using a raw water pump; a V-notch(13a); and a dephosphorization tub(2) and a first denitrification tank(3) receiving the raw water using an inlet valve installed on an inlet pipe.

Description

Membrane Treatment Device for Eliminating Nitrogen and / or Phosphorus

The present invention relates to a nitrogen, phosphorus removal membrane separation advanced processing apparatus, and more specifically, through the dephosphorization tank, the first denitrification tank, the second denitrification tank, aeration tank, membrane separation tank, stabilization tank, nitrogen in the wastewater, wastewater It is invented to increase the treatment efficiency by repeatedly purifying the wine, organics.

Combining the advantages of the existing activated sludge process and membrane technology, research has been conducted to replace the solid-liquid separation by gravity sedimentation with membrane separation to solve the disadvantages of the existing activated sludge process. Also called separation process or membrane-bound activated sludge process.

In addition, a combination of a general bioreactor and a membrane separation process is not limited to an activated sludge method and is called a membrane bioreactor (MBR).

The MBR process almost completely separates and removes substances (organic, inorganic contaminants, and microorganisms) present in raw water, wastewater, and wastewater according to the pore size (several to several tens of micrometers) and membrane surface charge of the separator. It is an advanced separation process.

In particular, in Korea, research is being actively conducted to combine the BNR (Biological Nutrient Removal) process, which is an advanced sewage treatment process, and the MBR process in accordance with the strengthened effluent water quality standards.

The characteristic of the MBR process is that it does not require a settling tank, it is possible to maintain the concentration of microorganisms 3 to 4 times higher than the activated sludge method, it is possible to effectively decompose organic matter at a smaller aerobic capacity, the sludge retention time (SRT) It can be maximized to induce nitrification, and since the amount of excess sludge is generated, the volume of the concentration tank is also reduced, thus enabling a compact process.

The advantage of the MBR process is that 100% of suspended solids can be removed, so that the treated water can be treated very stably (with BOD and SS less than 5 mg / L) regardless of sludge sedimentation properties. Large bacteria and viruses can be removed and treated water can be used as heavy water.

In addition, by installing the membrane unit in the aeration tank in the treatment plant to which the existing activated sludge process is applied, the construction is simple, economical and stable water quality can be obtained, the conversion from the existing activated sludge process to the membrane separation process is actively increasing.

The MBR process is capable of completely separating solid and liquid by a membrane than the conventional activated sludge process, and maintaining a high MLSS concentration (5,000 to 15,000 mg / L) in the reaction tank.

Such high microbial concentrations increase the efficiency of nitrification and increase the sludge residence time (SRT), thereby increasing the sludge assetization and reducing the sludge generation.

This may be an advantage of the MBR process because the cost of the sludge treatment occupies a large portion of the waste water treatment cost.

In addition, by using a membrane instead of the sedimentation basin can be reduced the cost and site required for the sedimentation basin.

Among the advantages of the MBR process, the most important point is that stable operation is possible.

In other words, there is no need to worry about sludge bulking, foaming, pin floc, etc. generated in the secondary sedimentation battery.In case of sludge expansion, smooth sedimentation and sedimentation of sedimentation basin cannot be performed. It causes a decrease in processing efficiency.

However, in MBR, stable sewage and wastewater treatment is possible because all of the expanded sludge is separated by a membrane.

The conventional MBR process is composed of a denitrification tank for denitrifying nitrate nitrogen using organic materials and an aerobic tank for converting ammonia nitrogen to nitrate nitrogen, and the treated water from which organic matter is removed through the membrane module in the aerobic tank is The water transported to the storage tank and mixed with sludge from the aeration tank is returned to the denitrification tank.

As described above, in order to remove nitrogen biologically, in most processes, the reaction tank is disposed in the order of denitrification tank and aerobic tank, and nitrate nitrogen generated in the aerobic tank is transferred to the denitrification tank using an internal transfer pump and piping.

In addition, since organic matter in the waste water and waste water is limited, it is generally returned to the inside for further denitrification only within 3 to 4 times the flow rate flowing therein, and the rest is discharged to the treated water.

In addition, since the nitrogen removal rate is greatly influenced by the water temperature of the reaction tank, the concentration of microorganisms, the characteristics of the inflow water, the time, the season, etc., it is very difficult to control the nitrogen concentration of the treated water below the regulated value, and therefore, when it exceeds the relief value, In addition, by adding an external carbon source to the denitrification tank, the denitrification efficiency is improved, and the amount of internal transport in the aerobic tank is controlled to remove nitrogen on a limited basis.

However, since the nitrate nitrogen, which is internally conveyed in the aerobic tank and flows out to the treated water, is essentially limited in nitrogen removal.

Therefore, when the influent C / N ratio is very low or when nitrogen and phosphorus are required as more stringent standards, it is difficult to treat only existing methods and additional processes are required.

In addition, the MBR process provides a higher concentration of DO compared to the conventional activated sludge process in order to delay the blockage inside the module of the membrane unit, reduce membrane contamination, and ultimately prolong the immersion chemical cleaning cycle and membrane life. Excess DO (2 ~ 4ppm) is supplied to the mixed liquid returned to the denitrification tank to prevent denitrification in the denitrification tank.

In addition, the MBR process has the advantage that the hydraulic retention time (HRT) is shortened when the sludge residence time (SRT) is increased due to high MLSS, but the land area can be reduced. It can cause a big problem in removing phosphorus.

That is, the long SRT may deteriorate the activity of the microorganisms, and the treated water quality may deteriorate. In view of nitrification, it is advantageous to operate the SRT for a long time, but it is disadvantageous from the viewpoint of phosphorus removal requiring a short SRT.

Therefore, the MBR process has good nitrification efficiency due to a long SRT by high microorganisms and a reduction in sludge generation due to sludge reoxidation, but may cause problems of deactivation of phosphorus and phosphorus removal.

As a result, the MBR process determines the treated water quality and sludge generation amount according to the SRT, and it is difficult to find a driving SRT that satisfies all nitrification, sludge generation, and phosphorus removal.

The present invention is to solve the conventional problems as described above to remove nitrogen efficiently even if the influent C / N ratio is low, the difficulty of phosphorus removal due to the long SRT pointed out as a disadvantage of the MBR process, the aeration of the membrane separation aeration tank By overcoming the difficulty of denitrification in the denitrification tank, the purpose of maximizing the merits of the MBR process to treat nitrogen and phosphorus more effectively.

In order to achieve the above object, the present invention provides a flow rate adjustment tank (1) for receiving the waste water filtered by the screen tank (10);

When the raw water flowing into the flow regulating tank 1 is above a predetermined level, the raw water of the flow regulating tank 1 is passed through the microfiltration screen 11 by a raw water pump immersed in the flow regulating tank 1. A dephosphorization tank 2 and a first denitrification tank 3 which are supplied at an appropriate ratio through an inlet valve installed in the inlet pipe via the V-NOTCH 13a;

When the raw water flowing into the first denitrification tank 3 is above a predetermined level, the mixed liquid in the second denitrification tank 4 is a second denitrification tank 4 which receives the raw water of the first denitrification tank 3. A second denitrification tank 4 for supplying the dephosphorization tank 2 to the dephosphorization tank 2 by an internal transfer pump 16 immersed in the second denitrification tank;

An aeration tank 5 for receiving the mixed liquid of the second denitrification tank 4 when the mixed liquid stored in the second denitrification tank 4 is equal to or higher than a predetermined level;

A membrane separation aeration tank (6) receiving the mixed liquid of the aeration tank (5) when the mixed liquid stored in the aeration tank (5) is above a predetermined level;

When the mixed liquid stored in the membrane separation tank 6 is a predetermined level or more, as a stabilization tank 7 supplied with the mixed liquid of the aeration tank 5, a conveying pump in which the mixed liquid in the stabilization tank 7 is immersed in the stabilization tank. A stabilization tank (7) for supplying the sludge storage tank (8) or the first denitrification tank (3) at an appropriate ratio through an inlet valve installed in the inlet pipe via a V-NOTCH (13b) by (15);

The mixture outside the membrane is introduced into the membrane through the membrane pores by the suction pressure generated by the operation of the suction pump 14 existing inside the membrane separation tank 6, and the suction pump 14 existing outside the membrane separation tank 6. A plurality of separation membrane units 18 for solid-liquid separation;

A coagulant storage tank 19 for storing a coagulant for coagulating and removing the phosphorus component and then supplying the stored coagulant to the aeration tank 5 by a transfer pump 17;

When the residue containing the nitrate small component and sludge remaining in the stabilization tank 7 is above a predetermined level, when the residue of the stabilization tank 7 is supplied, and the MLSS concentration in the membrane separation tank 6 is high. The sludge storage tank 8 which receives the sludge in the membrane separation tank 6, and the sludge storage tank 8 which supplies the sludge in the sludge storage tank to the flow rate adjusting tank 1 when it is at a predetermined level using an air lift pump. ;

A plurality of separator suction lines 21 installed between the plurality of separator units 18 and the suction pump 14 and provided with a differential pressure gauge for detecting the permeation pressure of the separator unit 18 and a suction valve for controlling the inflow of the treated water. )and;

A discharge tank 9 receiving the treated water sucked by the suction pump 14 and discharged to the outside by the discharge pump;

Air is supplied through the air line 22 to the air dispersing apparatus disposed below the separation membrane unit 18 immersed in the membrane separation tank 6, and the flow rate adjustment tank 1, the aeration tank 5, the reservoir tank The blower 12 which supplies air to 8 is comprised, respectively.

In addition, the raw water flowing through the microfiltration screen 11 is capable of measuring the flow rate flowing through the V-NOTCH (13a), and through the inlet valve installed in the inlet pipe and the dephosphorization tank (2) 1 is configured to flow into the denitrification tank (3).

And, the sludge conveyed from the stabilization tank (7) enables to measure the flow rate conveyed through the V-NOTCH (13b), the first denitrification tank (3) at an appropriate ratio through the inlet valve installed in the inlet pipe And, it is configured to be introduced into the reservoir storage tank (8).

As described above, according to the nitrogen, phosphorus removal membrane separation advanced processing apparatus according to the present invention, the denitrification tank is composed of two tanks, the first denitrification tank is a sludge containing DO and nitrate nitrogen components from the stabilization tank When the buffer is supplied to the DO and a predetermined level or more, and supplies a mixed solution to the second denitrification tank, the DO is supplied in a reduced state has the advantage of maximizing the efficiency of denitrification.

In addition, the raw water introduced through the microfiltration screen in the flow adjustment tank is introduced through the V-NOTCH without directly flowing into the single tank of the deining tank or the denitrification tank at the rear stage, so that the flow rate can be measured, and the proper ratio is provided through the installed inlet valve. (E.g., dephosphorization tank: denitrification tank = 3: 7) to control the amount of organic matter required for phosphorus release from the dephosphorization tank and the amount of organic matter required for denitrification in the first denitrification tank to remove nitrogen and phosphorus. There is an advantage to maximize the efficiency.

In addition, by forming an aeration tank in front of the membrane separation aeration tank, by reducing the concentration of organic matter to reduce the BOD load of the membrane separation aeration tank to minimize the impact on the membrane blockage, and to facilitate the maintenance of sewage and wastewater treatment plant, and separation membrane Can also maximize the lifetime.

1 is a process diagram of nitrogen, phosphorus removal membrane separation advanced processing apparatus according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, a preferred embodiment of the nitrogen, phosphorus removal membrane separation advanced processing apparatus according to the present invention will be described in detail.

1, the screen tank 10, the flow adjusting tank 1, the dephosphorization tank 2, the first denitrification tank 3, the second denitrification tank 4, and the aeration tank 5 as shown in FIG. , Membrane separation aeration tank (6), stabilization tank (7), sludge storage tank (8), discharge tank (9), microfiltration screen (11), blower (12), membrane unit (18) provided at the bottom of the air diffuser, A coagulant storage tank 19, a coagulant transfer pump 17, and V-NOTCHs 13a and 13b are included.

The screen tank 10, as raw water, which is waste water and waste water, is introduced into the water to be treated to remove contaminants in the waste water, thereby preventing clogging of the pump and mechanical failure in a subsequent process, and reducing the load of organic matter.

In addition, the flow rate adjusting tank 1 is located at a lower level than the screen tank 10 to receive the raw water filtered by the screen tank by natural falling.

The dephosphorization tank 2 is a microfiltration screen 11 by a raw water pump immersed in the flow rate adjustment tank the raw water of the flow rate adjustment tank 1 when the raw water introduced into the flow rate adjustment tank 1 is a predetermined level or more. Via the V-NOTCH (13a) through the inlet valve installed in the inlet pipe in accordance with the C / N ratio of the influent or nitrogen, phosphorus removal operation conditions, the raw water is supplied at an appropriate ratio.

In addition, the dephosphorization tank 2 is supplied with the mixed liquid in the second denitrification tank 4 by the internal transfer pump 16 immersed in the second denitrification tank.

The first denitrification tank 3, when the raw water introduced into the dephosphorization tank 2 is a predetermined level or more, the raw water of the dephosphorization tank is naturally supplied, and the microfiltration screen ( Through 11) and via V-NOTCH (13a), raw water is supplied at proper ratio through inlet valve installed in inlet pipe according to C / N ratio of influent or nitrogen, phosphorus removal operation condition.

The second denitrification tank 4 is naturally supplied with the first anoxic mixed solution when the mixed liquid introduced into the first denitrification tank 3 is equal to or higher than a predetermined level, and the mixed liquid in the second denitrification tank 4 is supplied. The dephosphorization tank 2 is supplied to the dephosphorization tank 2 by an internal transfer pump 16 immersed in the second denitrification tank.

The aeration tank 5 is naturally supplied with the raw water of the second denitrification tank when the raw water introduced into the second denitrification tank 4 is equal to or higher than a predetermined level.

In addition, when the mixed liquid stored in the aeration tank 5 is above a predetermined level, the membrane separation aeration tank 6 is naturally supplied with the mixed liquid of the aeration tank.

The stabilization tank 7 is naturally supplied with the mixed liquid of the membrane separation tank 6 when the mixed liquid stored in the membrane separation tank 6 is above a predetermined level.

The stabilization tank 7 is solid-liquid separated by the separation membrane unit 18 immersed in the membrane separation tank 6, and the stabilization tank 7 when the residue containing the residual nitric acid small component and sludge is more than a predetermined level. ) Through the inlet valve installed in the inlet pipe according to the site operating conditions via the V-NOTCH (13b) to the conveying pump (15) immersed in the tank (8) or the first denitrification tank (3) Supply.

The sludge storage tank 8 supplies the sludge in the sludge storage tank 8 to the flow rate adjusting tank 1 using an air lift pump when the sludge introduced from the stabilization tank 6 is equal to or higher than a predetermined level.

And, in order to remove the untreated phosphorus component in the aeration tank 5, the flocculant storage tank 19 stores a flocculant for flocculating and removing the phosphorus component, and then transfers the stored flocculant by the transfer pump 17. The aeration tank 5 is supplied.

Here, in the screen tank 10, the fixed bar screen and the automatic bar screen may be sequentially disposed to remove the coarse contaminants.

Moreover, the water flow stirrer 20 is arrange | positioned in each of the dephosphorization tank 2, the 1st denitrification tank 3, and the 2nd denitrification tank 4, respectively.

The water stirrer 20 provided in each of the dephosphorization tank 2, the first denitrification tank 3, and the second denitrification tank 4 is for properly mixing inflow raw water and return water and causing denitrification smoothly.

The blower 12 supplies air to an air diffuser disposed below the separation membrane unit 18 immersed in the membrane separation aeration tank 6 via an air line 22, and the flow rate adjustment tank 1 ), Air is supplied to the aeration tank 5 and the sludge storage tank 8, respectively.

Hereinafter, the nitrogen, phosphorus removal membrane separation advanced processing apparatus of the present invention configured as described above is as follows.

First, the raw water, which is the wastewater flowing into the present method, is removed through the fixed bar screen and the automatic bar screen of the screen tank 10, and the coarse contaminants are removed and flows into the flow regulating tank 1.

The flow rate adjusting tank 1 divides and supplies a predetermined amount of raw water into the dephosphorization tank 2 and the first denitrification tank 3, and each of the supply pipes is provided with an inlet valve for adjusting the flow rate of the lower and waste water. Will be supplied.

At this time, the raw water of the flow regulating tank 1 is filtered again by the microfiltration screen 11 before being transferred to the dephosphorization tank 2 and the 1st denitrification tank 3.

The microfiltration screen 11 is made of a fine mesh screen in a cylindrical shape, and is rotated by driving of a motor to remove fine contaminants.

The raw water transferred to the dephosphorization tank 2 is an internal conveying pump in a second denitrification tank 4 adjacent to the downstream side so as to maintain a mixed liquor suspended solids (MLSS) concentration of 5000 to 12000 mg / L (MLSS). The mixture is mixed with the return water conveyed by (16), and the mixture is agitated by the water flow stirrer 20 immersed in the dephosphorization tank 2, so that the mixture smoothly comes into contact with the microorganisms. Phosphorus components are eluted and released and some organic matter is removed.

Moreover, when raw water is more than a predetermined level in the dephosphorization tank 2, it discharges naturally to the said 1st denitrification tank 3 downstream.

In the said 1st denitrification tank 3, the conveyed water conveyed by the conveying pump 15 in the stabilization tank 7 also the mixture which the raw water divided-flowed in the flow regulating tank 1 inflowed in the said dephosphorization tank 2 also has And nitrate nitrogen components contained in the raw water and the return water of the dephosphorization tank 2 are removed by the denitrification reaction.

In addition, the nitrate nitrogen component that could not be removed in the first denitrification tank 3 is sequentially removed while passing through the second denitrification tank 4.

This is because the return water conveyed by the conveying pump 15 in the downstream stabilization tank 7 contains a large amount of DO components as well as nitrogen components modified with nitric acid nitrogen by nitric oxide microorganisms. The unreacted nitrate nitrogen, which is not properly denitrified, is set aside in the first denitrification tank (3) and the second denitrification tank (4) downstream so that the denitrification microorganism causes denitrification reaction smoothly in the absence of DO and removes nitrogen. This is to maximize the effect.

At this time, the organic carbon source necessary for the denitrification microorganism is supplied to the organic material in the inlet source water through the split inflow, in the process of biological metabolism of the dephosphorization microorganism in the dephosphorization tank (2) and the denitrification microorganism in the first denitrification tank (3). In order to maximize the effect of phosphorus and nitrogen removal at the same time by appropriately injecting the necessary organic matter (eg dephosphorization tank: denitrification tank = 3: 7).

As described above, the dephosphorization tank 2, the first denitrification tank 3, and the second denitrification tank 4 are suitably mixed with each other in order to smoothly discharge phosphorus and denitrification. The water flow stirrer 20 is installed in the 1st denitrification tank 3 and the 2nd denitrification tank 4, respectively, and raw water and return water are mixed.

When the denitrified mixture in the second denitrification tank 4 is above a predetermined level, the mixture is naturally introduced into the aeration tank 5.

In the mixture introduced into the aeration tank 5, organic pollutants, phosphorus substances, suspended solids, ammonia nitrogen (NH ₃ -N), nitrous nitrogen (NO ₂ -N) components are present.

The denitrification action refers to the action of reducing the nitrate nitrogen to nitrogen gas (N ₂ ) by the microorganism, and when the microorganism lacks oxygen, the oxygen contained in the nitric acid (NO ₃ ) is used to extract the oxygen. To lose, is reduced to nitrogen gas (N ₂ ) is released into the atmosphere.

There are many kinds of microorganisms involved in denitrification, but representative microorganisms include Pseudomonas and Bacillus.

On the other hand, denitrifying microorganisms belong to heterotrophic bacteria, so they need to be supplied with nutrients (carbon) from the outside for growth. Materials that can be used as an external carbon source include methanol, acetic acid, methane, and sewage.

 Chemical reaction formula with methanol

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

 Chemical reaction equation when using acetic acid

^{_{5CH 3 COOH + 8NO 3 - →}} 4N 2 + 10CO 2 + 6H 2 O + 8OH -

 Chemical Reactions When Using Methane

^{_{5CH 4 + 8 NO 3 - →}} 4N 2 + 5CO 2 + 6H 2 O + 8OH -

 Chemical reaction formula when using sewage

_{C 10 H 19 O 3 N +} 10NO 3 - → 5N 2 + 10CO 2 + 3H 2 O + NH 3 + 10OH -

In the aeration tank 5, MLSS (mixed liquor suspended solids: microorganism, 5000 to 12000 mg / L) at a concentration suitable for operating conditions is present, and the organic pollutant is consumed as a substrate of MLSS. It can reduce the BOD load of membrane separation tank and reduce membrane pore occlusion to extend membrane cleaning cycle and membrane life.

In addition, ammonia nitrogen (NH ₃ -N) and nitrous acid (NO ₂ -N) components contained in the mixture introduced into the aeration tank 5 are subjected to nitrification in an aerobic state through the aerobic state in the aeration tank 5. It is converted into the (NO ₃ -N) component, and the phosphorus component material is excessively absorbed and removed by the microorganisms in the aeration tank 5.

When the nitrified mixture in the aeration tank 5 is above a certain level, the mixture is naturally introduced into the membrane separation tank 6.

In the mixture introduced into the membrane separation tank (6), organic pollutants and phosphorus substances, suspended matter, ammonia nitrogen (NH ₃ -N), nitrous nitrogen (NO _2- ) that could not be removed in the aeration tank (5) N) component is present.

In the membrane separation tank 6, MLSS (mixed liquor suspended solids: microorganism, 5000 to 12000 mg / L) of a concentration corresponding to the operating conditions is present, and the organic pollutant is consumed as a substrate of the MLSS. do.

In addition, the ammonia nitrogen (NH ₃ -N) and nitrite nitrogen (NO ₂ -N) components contained in the mixture introduced into the membrane separation tank 6 are subjected to nitric acid in an aerobic state through the nitrification process in the membrane separation tank. To be converted to the nitrogen (NO ₃ -N) component.

The nitrification is a function of converting ammonia nitrogen (NH ₃ ) into nitrite nitrogen (NO ₂ ) or nitrate nitrogen (NO ₃ ) under aerobic conditions.

Among the nitrifying bacteria, the kind that converts ammonia to nitrite nitrogen is mainly Nitrosomonas, and the kind that changes to nitrate nitrogen is Nitrobacter.

The process of changing ammonia to nitric acid is represented by the following formula.

           Nitrosomonas

^{_{NH 4 + + 1.5O 2 → NO}} 2 - + H 2 O + 2H +

           Nitrobacter

^{_{NO 2 - + 0.5O 2 → NO}} 3 -

The energy generated when the ammonia nitrogen and the nitrite nitrogen are oxidized to the nitrate nitrogen is used for cell synthesis for growth of the nitric oxide.

The cell synthesis scheme by Nitrosomonas and Nitrobacter is as follows.

_{^{NH 4 + + HCO 3 - +}} 4CO 2 + H 2 O → C 5 H 7 O 2 N + 5O 2

The general formula including cell synthesis of nitrifying bacteria is as follows.

^{_{NH 4 + + 1.83O 2 + 1.98HCO}} 3 - → 0.021C 5 H 7 O 2 N + 0.98NO 3 - + 1.041H 2 O + 1.88H 2 CO 3

In the anaerobic condition, PAOs are hydrolyzed by polyphosphoric acid (Poly-P) in microbial cells and released as mixed phosphoric acid (PO ₄ -P). At the same time, organic matter in sewage and waste water is stored in cells as substrates such as PHA mainly composed of glycogen and PHB (poly hydrixybeta Butyrate).

In this case, the release rate of phosphorus is generally higher as the concentration of organic matter in the mixed solution is higher, and is usually released up to 3 to 5 times the concentration of inlet PO ₄ -P.

In the aerobic state as described above, the substrate stored in the cell is oxidized and decomposed to decrease.

PAOs microorganisms use the energy generated at this time to luxury uptake more than the amount required for the production of microorganisms in the anaerobic state by re-synthesizing into polyphosphoric acid.

Phosphorus Release Dephosphorization Conditions Poly -P + VFA PHB + PO ₄ ^3-

Phosphorus Exhalation Conditions PHB + PO ₄ ^{3 -} Poly -P + H ₂ O + CO ₂

Therefore, when the phosphorus component is removed by the microorganism, only the particulate matter such as suspended solids (SS) and MLSS is present in the membrane separation tank 6, which is solid-liquid separated by the membrane unit 18.

The membrane unit 18 is capable of performing solid-liquid separation in a state of being coupled to a known membrane frame device, which is a suction pump 14 and a suction line 21 existing outside the membrane separation tank 6. Is connected.

Due to the suction pressure generated by the operation of the suction pump 14, the mixture outside the separation membrane flows into the separation membrane through the separation membrane pores, and solid-liquid separation occurs, and finally, the treated water is removed by the suction pump 14. ) Will leak.

In order to delay the blockage occurring on the surface of the separator and to extend the operation time, an air diffuser (not shown and not shown) is installed at the bottom of the membrane frame device.

The air diffuser is connected to the blower 12 existing outside the membrane separation aeration tank 6 through the air line 22, and the air is supplied to the inside of the membrane separation aeration tank 6 through the operation of the blower 12. do.

Therefore, the water flow in the membrane separation tank 6 is formed by the air supplied through the blower 12, and the blockage of the membrane surface is delayed, so that the immersion type membrane separation advanced processing facility is smoothly operated for a long time.

In addition, MLSS concentration, SS and phosphorus substances in the membrane separation aeration tank 6 continue to increase during the long-term operation of the immersion membrane separation advanced treatment facility.

In order to maintain the appropriate MLSS concentration in the membrane separation tank 6 and to remove the SS and phosphorus substances, the remaining mixture is solid-liquid separated by the membrane separation unit 18 in the membrane separation tank 6 and has a predetermined level or more. The first denitrification tank 3 and the reservoir tank 8 through the inlet valve of the inlet pipe after passing through the V-NOTCH 13b by the conveying pump 15 in the stabilization tank. Will split into.

In order to remove the untreated phosphorus component, the flocculant storage tank 19 stores a flocculant for flocculating and removing the phosphorus component, and then stores the flocculant in the aeration tank 5 by the transfer pump 17. Supply.

In the reservoir tank 8, an air line 22 connected to the blower 12 is installed to prevent the sludge from sticking.

The treated water solid-liquid separated through the separation membrane unit 18 immersed in the membrane separation aeration tank 6 is sucked by the suction pump 14, supplied to the discharge tank 9, and discharged in the discharge tank. It is discharged to the outside by a pump or reused as heavy water.

1-flow control tank 2-dephosphorization tank
3-First denitrification tank 4-Second denitrification tank
5-Aeration tank 6-Membrane separation tank
7-Stabilization tank 8-Sludge tank
9-discharge tank 10-screen tank
11-Microfiltration Screen 12-Blowers
13a, 13b-V-NOTCH 14-suction pump
15-Return Pump 16-Internal Return Pump
17-transfer pump 18-separator unit
19-flocculant injection pump 20-water stirrer
21-Suction header 22-Airline

Claims (1)

A flow rate adjusting tank 1 for receiving the waste water filtered by the screen tank 10;
When the raw water flowing into the flow regulating tank 1 is above a predetermined level, the raw water of the flow regulating tank 1 is passed through the microfiltration screen 11 by a raw water pump immersed in the flow regulating tank 1. A dephosphorization tank 2 and a first denitrification tank 3 which are supplied at an appropriate ratio through an inlet valve installed in the inlet pipe via the V-NOTCH 13a;
When the raw water flowing into the first denitrification tank 3 is above a predetermined level, the mixed liquid in the second denitrification tank 4 is a second denitrification tank 4 which receives the raw water of the first denitrification tank 3. A second denitrification tank 4 for supplying the dephosphorization tank 2 to the dephosphorization tank 2 by an internal transfer pump 16 immersed in the second denitrification tank;
An aeration tank 5 for receiving the mixed liquid of the second denitrification tank 4 when the mixed liquid stored in the second denitrification tank 4 is equal to or higher than a predetermined level;
A membrane separation aeration tank (6) receiving the mixed liquid of the aeration tank (5) when the mixed liquid stored in the aeration tank (5) is above a predetermined level;
When the mixed liquid stored in the membrane separation tank 6 is a predetermined level or more, as a stabilization tank 7 supplied with the mixed liquid of the aeration tank 5, a conveying pump in which the mixed liquid in the stabilization tank 7 is immersed in the stabilization tank. A stabilization tank (7) for supplying the sludge storage tank (8) or the first denitrification tank (3) at an appropriate ratio through an inlet valve installed in the inlet pipe via a V-NOTCH (13b) by (15);
The mixture outside the membrane is introduced into the membrane through the membrane pores by the suction pressure generated by the operation of the suction pump 14 existing inside the membrane separation tank 6, and the suction pump 14 existing outside the membrane separation tank 6. A plurality of separation membrane units 18 for solid-liquid separation;
A coagulant storage tank 19 for storing a coagulant for coagulating and removing the phosphorus component and then supplying the stored coagulant to the aeration tank 5 by a transfer pump 17;
When the residue containing the nitrate small component and sludge remaining in the stabilization tank 7 is above a predetermined level, when the residue of the stabilization tank 7 is supplied, and the MLSS concentration in the membrane separation tank 6 is high. The sludge storage tank 8 which receives the sludge in the membrane separation tank 6, and the sludge storage tank 8 which supplies the sludge in the sludge storage tank to the flow rate adjusting tank 1 when it is at a predetermined level using an air lift pump. ;
A plurality of separator suction lines 21 installed between the plurality of separator units 18 and the suction pump 14 and provided with a differential pressure gauge for detecting the permeation pressure of the separator unit 18 and a suction valve for controlling the inflow of the treated water. )and;
A discharge tank 9 receiving the treated water sucked by the suction pump 14 and discharged to the outside by the discharge pump;
Air is supplied through the air line 22 to the air dispersing apparatus disposed below the separation membrane unit 18 immersed in the membrane separation tank 6, and the flow rate adjustment tank 1, the aeration tank 5, the reservoir tank Nitrogen, phosphorus removal membrane separation advanced processing apparatus, characterized in that it comprises a blower (12) for supplying air to (8), respectively.

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