KR100566320B1 - Submerged membrane coupled advanced wastewater treatment method and its system - Google Patents

Abstract

The present invention relates to an advanced wastewater treatment method and apparatus for simultaneously treating organic matter, nitrogen, and phosphorus in wastewater, and in particular, two reactors arranged in parallel and having no inflow and outflow between each other, and one MBR reactor having a subsequent membrane immersed therein. The present invention relates to an advanced method and apparatus for immersion type membrane-coupled sewage treatment system using the intermittent aeration and flow path changing method. In the present invention, the amount of conveying sludge is reduced to 1Q or less of influent, and the inflow source is not supplied with air. The flow path is changed to supply only to the reaction tank in which the air is not supplied, and the return sludge is supplied only to the reaction tank in which the air is supplied. The reactor operated by the exhalation tank is operated without supplying air for a certain time to completely exclude the influence of dissolved oxygen in the sludge. Advanced wastewater treatment method and apparatus utilizing dissolved oxygen depletion stage Is provided. According to the present invention can minimize the loss of organic matter, in particular organic matter such as SCVFA can greatly improve the treatment efficiency of nitrogen and phosphorus.

Intermittent Aeration, Flow Change, Nitrogen, Phosphorus, Membrane, Wastewater, Return Sludge, Dissolved Oxygen

Description

Submerged membrane coupled advanced wastewater treatment method and its system

Figure 1 shows the basic configuration of the wastewater treatment apparatus of the present invention consisting of two reactors arranged in parallel, followed by one MBR reactor.

Figure 2a and b is an embodiment of the present invention is operated as a wastewater treatment system having a stirring facility and an inflow control means, 2a is a step 1-A and 1-B, 2b is a step 2-A and 2-B It is shown.

3A and 3B illustrate an embodiment of the present invention in which the agitation is performed in the first and second reaction tanks and operated as a wastewater treatment system configured to freely flow in and out between the first and second reactors and the MBR reaction tank. Steps 1-A and 1-B and 3b show steps 2-A and 2-B.

4A and 4B illustrate an embodiment of the present invention operated as a wastewater treatment system in which agitation in the first and second reaction tanks is not performed and flow in and out between the first and second reaction tanks and the MBR reaction tank is freely performed. Shows steps 1-A and 1-B and 4b shows steps 2-A and 2-B.

FIG. 5 is one temporary view of the hydrological flow path changing means, FIG. 5A is a perspective view, FIG. 5B is a plan view, FIG. 5C is a state diagram in steps 1-A and 1-B of the present invention, and FIG. 5D is 2-A and This is a state diagram in step 2-B.

Figure 6 is an embodiment of the valve-type flow path changing means for installing and operating a valve in the pipe, Figure 6a is a state diagram in steps 1-A and 1-B of the present invention, Figure 6b is 2-A and 2- This is a state diagram in step B.

<Explanation of symbols for main parts of drawing>

20: first reactor 21: second reactor

23: first flow control means 24: second flow control means

30: MBR reactor 31: separation membrane

40: flow path changing means 50: controller 1

51: controller 2

The present invention relates to an advanced wastewater treatment method and apparatus for simultaneously treating organic matter, nitrogen, and phosphorus in wastewater, and in particular, two reactors arranged in parallel and having no inflow and outflow between each other, and one MBR reactor having a subsequent membrane immersed therein. The present invention relates to a submerged membrane-coupled sewage wastewater treatment method and apparatus having a basic configuration and applying an intermittent aeration and flow path changing method.

Sewage treatment process (MBR) operated by immersing the membrane in the activated sludge aeration basin are usually becomes the aerobic reaction tank in which the anaerobic or anoxic tank disposed at the front end is immersed in a membrane at the rear end being arranged, most of the conventional sewage treatment technologies A ² / Membrane is applied based on similar process as O. This process has a big problem that the organic matter in the influent is lost due to the dissolved oxygen in the sludge due to excessive internal and external sludge conveyance of 2 to 6 Q, thereby lowering the nitrogen and phosphorus removal efficiency. In particular, the existing sewage treatment process is intensifying this problem because almost all of the sludge generated in the final sedimentation tank or the aerobic tank is developed to be mixed with the influent or returned to the same reactor.

As a prior art to solve this problem, there is an attempt to solve the problem by placing a separate dissolved oxygen depletion tank or a reduction tank at the end of the aeration tank, but this requires a separate reaction tank installation to increase the construction and maintenance costs Becomes

In addition, in recent years, the advanced treatment process has been developed by operating the reaction tank or temporal reaction tank to change the inflow direction of the inflow water over time, away from the conventional spatial methods such as A / O, A ² / O and Bardenpho process. have. Representative technologies of the temporal method include PID (Phased Isolation Ditch) and DeNiPho (DeNiPho), and improved technologies that change the system configuration or operation method based on these main methods (domestic) Japanese Patent Application Laid-Open No. 2001-97869 and the like) are also disclosed.

However, even in such a temporal method, the decrease in efficiency due to dissolved oxygen in the conveying sludge cannot be ruled out. In particular, when the amount of the conveying sludge is large, the dissolved oxygen has a great influence on the treatment efficiency.

The present invention is to solve such a conventional problem and to achieve the maximum removal efficiency at a given influent condition, the present invention is to continuously run the inflow of wastewater, while smoothly and easily operating the organic matter by dissolved oxygen in the conveying sludge It aims to greatly improve the processing efficiency by eliminating losses.

In addition, an object of the present invention is to provide an efficient system configuration and operation method that can significantly reduce the amount of the conveying sludge itself.

The use of organics in biological advanced processing techniques is very important. The main method used in the temporal advanced processing process is to form anaerobic, anaerobic and aerobic conditions by turning on or off the air supply, where the organic matter is required to release phosphorus and anaerobic conditions under anaerobic conditions. Denitrification at Therefore, when inflow water is supplied under the condition that the air is not supplied, the removal efficiency is improved, but when the inflow water is supplied under the air supply condition, loss of organic matter occurs and nitrogen and phosphorus removal efficiency are lowered. In particular, when treating wastewater with a low C / N ratio in influent, as in Korea, the removal efficiency of nitrogen and phosphorus is highly dependent on the utilization of organic materials, so the supply method of influent is an important problem. However, even when the inflow source water is improved under the condition that no air is supplied, the loss of organic matter by dissolved oxygen present in the sludge cannot be excluded. In particular, organic matters required for denitrification and phosphorus release are readily biodegradable organic matters or short-chain volatile fatty acids (SCVFAs), which are easily decomposed by microorganisms rather than the total amount of BOD and COD, which are ordinary organic matters. Most sewage in the sewage is relatively low, with 9-25% of total organic matter. In the presence of dissolved oxygen or activated sludge, decomposition occurs rapidly. Therefore, if dissolved oxygen is present in the returning sludge and the returning sludge is mixed with the inflow water and introduced into the aeration tank or mixed with the inflow water at the front end of the aeration tank, the organic material which is easy to decompose microorganisms causes rapid decomposition and greatly denitrification and phosphorus emission efficiency. As it affects, there is a need for a method for minimizing the effects of dissolved oxygen in the conveying sludge.

Accordingly, in the present invention, the amount of return sludge is 1Q of influent water as an efficient system configuration and operation method based on two inflow reaction tanks operated by intermittent aeration without subsequent inflow and outflow followed by an MBR reaction tank operated continuously as an exhalation unit. At the same time, the incoming water is supplied only to the reactor with no air supplied and the return sludge is supplied only to the reactor supplied with air, and the reactor operated by aerobic tank completely eliminates the influence of dissolved oxygen in the sludge. In order to minimize the loss of organic matter, especially organic matter such as SCVFA, by providing a dissolved oxygen depletion step that operates for a certain time without supplying air, a wastewater treatment method and apparatus can be greatly improved the treatment efficiency of nitrogen and phosphorus. To provide.

In the present invention,

In the wastewater treatment method applying intermittent aeration and flow path changing method,

First and second reactors arranged in parallel and operated with intermittent aeration and free from each other; Subsequently installed, the membrane is immersed and maintained in an aerobic state at all times, and one MBR reactor is used as the basic configuration of the wastewater treatment system.

(a) The first reactor is operated in aerobic state with abandonment, the second reactor is operated as aeration machine, the inflow of water flows into the second reactor only, and the return sludge from the MBR reactor enters the first reactor only (1-A )Wow;

(b) The flow path of inflow water and return sludge is the same as in step 1-A, the first reactor is operated with the abandonment of aeration, and the second reactor is continuously operated with aeration machine to introduce the sludge introduced into the first reactor. Depleting dissolved oxygen in the water (1-B);

(c) In contrast to step 1-A, the second reactor is operated in aerobic state with abandonment, the first reactor is operated with aeration, the inflow of water flows into the first reactor only, and the return sludge from the MBR reactor is only the second reactor. Inflow step (2-A);

(d) The flow path of inflow water and return sludge is the same as in step 2-A, and the second reactor is operated with the abandonment of aeration and the first reactor continuously operated with aeration machine, and the sludge introduced into the second reactor is introduced. Provided is a high wastewater treatment method comprising the step (2-B) of depletion of dissolved oxygen in water.

In an embodiment of the present invention, the above steps are repeated in the order of 1-A → 1-B → 2-A → 2-B to treat sewage water. Preferred set time ratios of 1-A to 1-B and 2-A to 2-B are 2: 1 to 1: 2.

In still other embodiments of the present invention, the sequence 1-A → 1-B → 1-A → 2-A → 2-B → 2-A or 1-B → 1-A → 1-B → 2-B → The above steps are repeated in the order 2-A → 2-B to treat the wastewater.

In one embodiment of the invention,

The wastewater treatment system is set to agitate in the first and second reaction tanks, and to control the inflow and outflow between the first reaction vessel and the MBR reaction vessel and between the second reaction vessel and the MBR reaction vessel,

In steps 1-A and 1-B, the inflow and outflow between the first reaction vessel and the MBR reaction vessel is freely made, and the inflow and outflow between the second reaction vessel and the MBR reaction vessel is not made,

In the 2-A and 2-B steps, the inflow and outflow between the second reaction vessel and the MBR reaction vessel is freely made, and the inflow and outflow between the first reaction vessel and the MBR reaction vessel is operated.

In another embodiment of the invention,

The wastewater treatment system is set such that agitation is performed in the first and second reaction tanks, and flow in and out between the first and the MBR reaction tanks and between the second and the MBR reaction tanks is freely performed.

The steps 1-A, 1-B, 2-A, and 2-B are operated to smoothly circulate without generating water head difference between the first reactor and the MBR reactor and between the second reactor and the MBR reactor.

In another embodiment of the invention,

The wastewater treatment system is set so that the agitation is not performed in the first and second reaction tanks, and the inflow and outflow is freely performed between the first and the MBR reaction tanks and between the second and the MBR reaction tanks.

The sludge blanket layer of the first and second reactors is operated to uniformly pass the inflow of the inlet water to cause denitrification and phosphorus release.

In the present invention, the inlet source water is supplied only in aeration conditions in order to effectively utilize the organic matter required for denitrification, and the flow path is set so that the return sludge is supplied to a different reaction tank from the inlet water to prevent the loss of organic matter due to dissolved oxygen in the return sludge. It is supplied only to the reaction tank which is the aeration condition, and the reaction tank supplied with the return sludge is operated without supplying air for a predetermined time out of the time set as the aerobic condition before switching to the non-aeration tank, that is, 1-A (2-A) By placing the 1-B (2-B) step before, after, or in between, the effect of dissolved oxygen in the conveying sludge is completely eliminated.

In the present invention,

(a) a first and a second reaction tank disposed in parallel with the raw water inflow unit, having no inflow and outflow between each other, and having intermittent aeration means;

(b) Treated water discharging means and sludge conveying means, which are subsequently installed in the first and second reaction tanks so that the membrane is immersed, maintained in an exhaled state, and the reaction tank and flow in and out of the shear are discharged, and the treated water is discharged through the membrane. It is provided with one MBR reaction tank;

(c) The inflow of wastewater and returning sludge is provided in a continuous manner, and a wastewater treatment apparatus including flow path changing means for setting the inflow of the inflowing water and the returning sludge to be supplied to different reactors for the first and second reactors is provided. .

Preferably, the flow path changing means is automatically controlled in conjunction with the intermittent aeration means.

The wastewater treatment apparatus of the present invention may further include an inflow and outflow control means for controlling the inflow and outflow between the first and second reaction tanks and the MBR reaction tank.

As used herein, "wastewater" and "wastewater" include all wastewater, such as sewage, sewage, general wastewater, and livestock wastewater.

Hereinafter, with reference to the accompanying drawings will be described in detail preferred embodiments of the immersion membrane coupled sewage treatment method and apparatus of the present invention in detail. In the constitution of the present invention, the same constitution as that of the conventional sewage water treatment apparatus is omitted without departing from the technical spirit of the present invention. In addition, in order to make an understanding of this invention easy, the reference numeral of the accompanying drawings is shown in parentheses, but the present invention is not limited to the form shown by it.

Figure 1 shows the basic configuration of the wastewater treatment apparatus of the present invention consisting of two reactors arranged in parallel, followed by one MBR reactor.

The first and second reactors 20 and 21 are arranged in parallel in the lateral direction of the inflow portion into which the raw water flows, and the MBR reaction tank 30 in which the membrane is immersed is subsequently disposed in the first and second reactors. The first and second reaction tanks 20 and 21 are provided with intermittent aeration means and operated as intermittent aeration, and the MBR reaction tank 30 is always maintained in an exhalation state.

The wastewater treatment apparatus of the present invention includes a flow passage changing means 40 for changing the flow path of the inflow water and the conveying sludge, and the treatment water discharge means such as the suction pump 34 and the sludge conveying pump 32 and the sludge in the MBR reaction tank. Sludge conveying means, such as the conveying line 33, is provided.

In addition, the wastewater treatment apparatus is installed in the first and second reaction tanks, and the stirring means 22 for mixing the wastewater and microorganisms, between the first reaction tank 20 and the MBR reaction tank 30, and the second reaction tank 21 and the MBR. Is installed between the reaction tank 30 may optionally include a flow inlet control means (23, 24) and the like to control the flow in and out between the reaction tank.

The intermittent aeration means includes a blower 60 for injecting air into the first and second reactors and an air supply control device (not shown) such as a solenoid valve, an electric valve, or a timer for changing the supply of air at regular intervals. It may include. The air supply control device may be installed on a pipe connecting the broa 60 and the diffuser 61.

The flow path changing means 40 may be operated at a predetermined time setting by an automatic control facility 50 or 51 such as a timer or a PLC, interlocked with the intermittent aeration means, and the inflow water flowing in continuously through the screen 10. And the return sludge from the MBR reactor 30 is selectively supplied to the first reactor 20 or the second reactor 21. The flow path changing means 40 may have various forms within a range capable of performing the function. As an example, an integral hydrologic type or a valve type including a flow path change part of the inflowing water and a flow path change part of the conveying sludge may be provided, which will be described below with reference to FIG. 5.

Outflow control means (23, 24) installed between the reaction tank (20, 21) and the MBR reaction tank 30 is to control the flow between both reaction tanks, various types such as valve type or water gate type is possible, timer , PLC and so on.

Control device 1 (50) shown is on / off of the intermittent aeration means provided in the first and second reactors (20, 21), stirrer operation, flow path changing means (40), outflow control means (23). 24) and the like, and the control device 2 (51) can perform various control functions in connection with the control device 1 (50) as a PLC or automatic control equipment.

2 to 4 show step by step embodiments of the advanced wastewater treatment method of the present invention.

The embodiment of FIG. 2 is provided with agitation means 22 in the first and second reaction tanks and flow-in and out control means 23 and 24 between the first and second reaction tanks and the MBR reaction tank. It operates as a wastewater treatment system in which the inflow and outflow between the second reactor and the MBR reactor is controlled. FIG. 2A shows the following steps 1-A and 1-B, and FIG. 2B shows the following steps 2-A and 2-B to treat the introduced wastewater by repeating these steps.

Step 1-A

The first reactor is operated in aerobic state with abandonment, the second reactor is operated with aeration machine, the inflow of water flows only into the second reactor and the return sludge from the MBR reactor flows only into the first reactor. The inflow and outflow control means 23 between the first reactor 20 and the MBR reactor 30 is opened to freely circulate both reaction tanks, and the influent flows through both reactors, causing sufficient nitrification. At this time, the inflow and outflow control means 24 between the second reaction tank 21 and the MBR reaction tank 30 is closed so that the inflow and outflow is not performed between the second reaction tank and the MBR reaction tank.

1-B step

The first reactor operates with abandonment and the second reactor continues to run as aerosol to deplete dissolved oxygen in the sludge introduced into the first reactor. The inflow and outflow between the flow of inflow water and the return sludge and the reaction tank is the same as in step 1-A.

2-A step

The operation is reversed from the steps 1-A. That is, the second reactor is operated in aerobic state by abandonment, the first reactor is operated by aeration, the inflow source is only introduced into the first reactor and the return sludge from the MBR reactor is only introduced into the second reactor. The inflow and outflow control means 24 between the second reactor 21 and the MBR reaction tank 30 is opened to freely circulate between the two reaction tanks, and the inflow water circulates both reaction tanks so that sufficient nitrification occurs. At this time, the inflow and outflow control means 23 between the first reaction vessel 20 and the MBR reaction vessel 30 is closed so that the inflow and outflow is not performed between the second reaction vessel and the MBR reaction vessel.

2-B step

The second reactor operates without stopping the aeration and the first reactor continues to run as aerosol to deplete dissolved oxygen in the sludge introduced into the second reactor. The inflow and outflow between the flow of inflow water and the return sludge and the reaction tank is the same as in step 2-A.

In the 1-A, 1-B, 2-A, and 2-B stages, no inflow and outflow occurs between the first reactor and the second reactor, and the MBR reactor 30 is an activated sludge reactor in which the membrane is immersed for 24 hours. And the sludge conveying pump 32 and the sludge conveying line 33 are discharged from the treated water through the membrane by an operating method based on a predetermined time interval or an upper and lower water level. , 21).

Advanced wastewater treatment method of the present invention is 1-A → 1-B → 2-A → 2-B, or 1-A → 1-B → 1-A → 2-A → 2-B → 2-A In order to treat the introduced wastewater by repeating the above steps in various forms, such as 1-B → 1-A → 1-B → 2-B → 2-A → 2-B. When repeating each step in the order 1-A → 1-B → 2-A → 2-B, the ratio of step A to step B, that is, 1-A to 1-B and 2-A to 2-B The set time ratio is usually in the range of 2: 1 to 1: 2. Depending on the characteristics of the wastewater, 1-A → 1-B → 1-A → 2-A → 2-B → 2-A or 1-B → 1-A → 1-B → 2-B → 2-A → It can be operated in various forms, including the 2-B sequence, in which the ratio of the set time of step A to step B can be variously modified.

Reactors operated in an aerobic state (oxic) at each stage maximize the nitrification reaction, and phosphorus absorption occurs. Non-aerobic reactors induce denitrification by using organic matter in the influent. It is converted to nitrogen gas and released into the atmosphere for final treatment. Phosphorus release occurs.

The steps 1-B and 2-B are operated as a step of operating a predetermined period of time in a predetermined expiration time of each reactor without supplying air, and are used as an oxygen depletion time to deplete dissolved oxygen in the sludge. For example, in the 1-A stage, the air is supplied to the first reactor for 40 minutes, and the flow goes to the 1-B stage for 20 minutes without oxygen. The air is supplied for a minute and then goes to step 2-B to operate for 20 minutes without oxygen supply. The oxygen depletion time (1-B and 2-B) can be set differently according to water temperature and other water quality factors (DO, ORP, ammonia nitrogen sensor, etc.) according to the winter season and summer season. It is also possible to control automatically considering the factor.

In addition, in the method of discharging the final treated water from the MBR reactor 30, the flow rate 35 is installed at the discharge point of the final treated water, so that the number of revolutions of the suction pump 34 is discharged so that the constant treated water is discharged based on the flow rate of the flowmeter. Can be operated with automatic feedback adjustment.

3 is operated with a wastewater treatment system provided with agitating means 22 to stir in the first and second reactors and to allow free flow in and out between the first and second reactors and the MBR reactor. . 3A shows steps 1-A and 1-B, and FIG. 3B shows steps 2-A and 2-B.

1-A, 1-B, 2-A, and 2-B in the step 2 except that the water cycle does not occur between the first reactor and the MBR reactor and between the second reactor and the MBR reaction tank and the circulation is smoothly performed. Same as the operating method of the embodiment shown in.

4 is operated by the wastewater treatment system set so that the inflow and outflow between a 1st and 2nd reaction tank and an MBR reaction tank is made free, without stirring in a 1st and 2nd reaction tank. 4A shows steps 1-A and 1-B and FIG. 4B shows steps 2-A and 2-B.

Stirring in the first and second reactors is not carried out, evenly flowing the inlet water through the sludge layer below the first and second reactors, that is, the sludge blanket layer that appears in the high concentration of mixed liquor suspended solids (MLSS). It is the same as the operation method of the embodiment shown in FIG. 3 except that the denitrification and phosphorus release to operate.

5 and 6 show an embodiment of the flow path changing means used in the present invention.

5 is an example of the hydrological flow path changing means in which the flow path changing part of the inflowing water and the flow path changing part of the conveying sludge are integrally formed, FIG. 5A is a perspective view of the flow path changing means, and FIG. 5B is a plan view. As shown, the hydrologic flow channel changing means has two distribution tanks 41 and 41 'through which the inflow water and the conveying sludge flow in and out, respectively, and the overflow plates 42 and 42' are installed in each distribution tank. It is. Each distribution tank 41, 41 'is provided with a sluice 44,44' only on the side where the inflows 43, 43 'of inflow water (or sludge) are located with the overflow plates 42, 42' interposed therebetween. On the opposite side of the water gates 44 and 44 ', openings 45 and 45' are provided so that inflow water (or sludge) can freely flow out. Therefore, inflow water (or conveying sludge) flows out through the gate in the state where the gates 44 and 44 'are opened, and beyond the overflow plates 42 and 42' in the state where the gates 44 and 44 'are closed. It flows out through openings 45 and 45 'in opposite directions. The two gates can be opened and closed simultaneously by a single control system to automatically control the flow of influent and returning sludge to different reactors. Such hydrological flow path changing means is suitable for a relatively large treatment plant.

Fig. 5C shows the state of the flow path changing means in steps 1-A and 1-B of the present invention, and Fig. 5D shows the state of the flow path changing means in steps 2-A and 2-B. In steps 1-A and 1-B shown in FIG. 5C, both of the water gates 44 and 44 ′ are opened, and the inflow water entering the distribution tank 41 is transferred to the second reaction tank 21 through the water gate 44. The supply sludge, which is supplied to the distribution tank 41 ', is supplied to the first reaction tank 20 through the water gate 44'. In steps 2-A and 2-B shown in FIG. 5D, inflow water entering the distribution tank 41 by closing the two water gates 44 and 44 ′ is oppositely opened beyond the overflow plate 42. ) Is supplied to the first reactor 21, and the conveying sludge entering the distribution tank 41 ′ is supplied to the second reactor 21 via the opening 45 ′ over the overflow plate 42 ′.

Fig. 6 shows a flow path changing means for installing and operating a valve in the pipe, inflow pipe (inflow water supply line) 11 of inflow water and transport pipe (conveyance line) 33 of sludge are shown in FIG. It is connected to the reactor. The inflow water pipe 11 and the sludge conveying pipe 33 are provided with valves 46 and 47, respectively, and when the valve is opened, the inflow water is supplied to the second reactor and the sludge is supplied to the first reactor. On the contrary, when the valves of the two pipes are closed, the inflow water and the conveying sludge do not flow in the existing flow direction, but overcome the constant hydraulic load and flow in the opposite direction. The opening and closing of the valve may be operated at a time set by an automatic control facility such as a timer and a PLC, and such a valve-type flow path changing means is suitable for a relatively small treatment plant. Fig. 6A shows the state of the flow path changing means in steps 1-A and 1-B of the present invention, and Fig. 6B shows the state of the flow path changing means in steps 2-A and 2-B. In steps 1-A and 1-B shown in FIG. 6A, both the valve 46 of the influent pipe 11 and the valve 47 of the sludge conveying pipe 33 are opened so that the influent water is supplied to the second reactor. Sludge is fed to the first reactor. In the 2-A and 2-B steps shown in FIG. 6B, the valves 46 and 47 of the two pipes 11 and 33 are closed, thereby overcoming a constant hydraulic load in which the influent and the conveying sludge are overcome, Proceeding, inflow water is supplied to the first reactor and sludge is supplied to the second reactor.

The main features of the sewage treatment system and operation method according to the present invention can be applied to the case where one reactor is located in front of the MBR reactor.

Example 1

The wastewater was treated according to the apparatus shown in FIG. 1 and the operating method of FIG. 2. Chemical oxygen demand (TCODcr) of 150 mg / L, total nitrogen (TN) of 70 mg / L, and total phosphorus (TP) of 3 mg / L The inflow water and the return sludge flow change time were 60 minutes, and the total hydraulic residence time was 6 hours, and the hydraulic retention time of the MBR reactor was 2.3 hours. As a result, the chemical oxygen demand of the treated water was less than 10 mg / L, and the concentrations of total nitrogen (TN) and total phosphorus (TP) were 20 mg / L and 1 mg / L, respectively. .

The immersed membrane-coupled sewage wastewater advanced treatment method and apparatus of the present invention can reduce the operating cost of the system by maintaining the amount of conveying sludge to 1Q or less as an efficient system configuration and operation method, decomposition of organic matter in influent, in particular, such as SCVFA It is very effective for the treatment of nitrogen and phosphorus in Korea's wastewater with low C / N ratio because it can prevent the loss of organic matter which is very easy and utilize it for denitrification and phosphorus release. In addition, since the system configuration does not require a separate settling basin or a subsequent filtration device, the operation is simple and inexpensive, and the installation cost of the solid-liquid separator including the membrane outside the reactor can greatly reduce the membrane installation cost. have.

Claims (11)

In the wastewater treatment method applying intermittent aeration and flow path changing method, First and second reactors arranged in parallel and operated with intermittent aeration and free from each other; Subsequently installed, the membrane is immersed and maintained in an aerobic state at all times, and one MBR reactor is used as the basic configuration of the wastewater treatment system. (a) The first reactor is operated in aerobic state with abandonment, the second reactor is operated as aeration machine, the inflow of water flows into the second reactor only, and the return sludge from the MBR reactor enters the first reactor only (1-A )Wow; (b) The flow path of inflow water and return sludge is the same as in step 1-A, the first reactor is operated with the abandonment of aeration, and the second reactor is continuously operated with aeration machine to introduce the sludge introduced into the first reactor. Depleting dissolved oxygen in the water (1-B); (c) In contrast to step 1-A, the second reactor is operated in aerobic state with abandonment, the first reactor is operated by aeration, the inflow of water flows into the first reactor only, and the return sludge from the MBR reactor is only the second reactor. Inflow step (2-A); (d) The flow path of inflow water and return sludge is the same as in step 2-A, and the second reactor is operated with the abandonment of aeration and the first reactor continuously operated with aeration machine, and the sludge introduced into the second reactor is introduced. Depletion of dissolved oxygen in (2-B); Advanced wastewater treatment method comprising a. The method according to claim 1,  1-A → 1-B → 2-A → 2-B. The above steps are repeated by the above steps. The method according to claim 2, The set time ratio of step 1-A to step 1-B and the set time ratio of step 2-A to step 2-B are 2: 1 to 1: 2, respectively. The method according to claim 1, 1-A → 1-B → 1-A → 2-A → 2-B → 2-A, and repeating the above steps in the order of advanced wastewater treatment. The method according to claim 1, 1-B → 1-A → 1-B → 2-B → 2-A → 2-B The above steps are repeated in the order of advanced wastewater treatment. The method according to any one of claims 1 to 5, The wastewater treatment system is agitated in the first and second reaction tanks, and is configured to control the inflow and outflow between the first and the MBR reaction tanks and between the second and the MBR reaction tanks. In steps 1-A and 1-B, the inflow and outflow between the first reaction vessel and the MBR reaction vessel is freely made, and the inflow and outflow between the second reaction vessel and the MBR reaction vessel is not made, In the 2-A and 2-B step, the flow of inflow between the second reactor and the MBR reactor is free, and the flow of inflow between the first reactor and the MBR reactor is not made. The method according to any one of claims 1 to 5, The wastewater treatment system is set such that agitation is performed in the first and second reaction tanks, and flow in and out between the first and the MBR reaction tanks and between the second and the MBR reaction tanks is freely performed. The 1-A, 1-B, 2-A, 2-B step wastewater altitude, characterized in that the circulation is smoothly generated without the head difference between the first reactor and the MBR reactor and between the second reactor and the MBR reactor Treatment method. The method according to any one of claims 1 to 5, The wastewater treatment system is set so that the agitation is not performed in the first and second reaction tanks, and the inflow and outflow is freely performed between the first and the MBR reaction tanks and between the second and the MBR reaction tanks. An advanced treatment method for sewage water, characterized in that the denitrification reaction and phosphorus release occur by uniformly passing the inflow of water into the sludge blanket layer of the first and second reactors. delete (a) a first and a second reaction tank disposed in parallel with the raw water inflow unit, having no inflow and outflow between each other, and having intermittent aeration means; (b) Treated water discharging means and sludge conveying means, which are subsequently installed in the first and second reaction tanks so that the membrane is immersed, maintained in an exhaled state, and the reaction tank and flow in and out of the shear are discharged, and the treated water is discharged through the membrane. It is provided with one MBR reaction tank; (c) the inflow of the inflow water and the return sludge is continuously made, but the inflow of the inflow water and the return sludge is set to be alternately supplied to the different reaction tanks for the first and second reaction tanks, and is automatically controlled in conjunction with the intermittent aeration means. A wastewater treatment apparatus comprising a flow path changing means. The wastewater treatment apparatus according to claim 10, further comprising an inflow control means for controlling the inflow and outflow between the first and second reaction tanks and the MBR reaction tank.

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