KR20140085720A - Treatment system of wastewater containing ammonium nitrogen and nitrite nitrogen - Google Patents

Abstract

Disclosed is a treatment system for wastewater containing ammonium nitrogen and nitrite nitrogen that is capable of improving biomass stay in a reactor, ensuring continuous nutrient salt injection, addressing the problem of reactivity reduction caused by air contact occurring during cleaning of biomass recovery means, and addressing the problem of reaction efficiency reduction attributable to a reaction tank pause. The present invention, which is a treatment system for wastewater containing ammonium nitrogen and nitrite nitrogen using biomass containing an autotrophic denitrifying microorganism and capable of producing nitrogen gas by reacting the ammonium nitrogen as an electron donor and the nitrite nitrogen as an electron acceptor in an anoxic condition, includes a biological reaction tank where the wastewater containing the ammonium nitrogen and the nitrite nitrogen flows in, a denitrification reaction is performed by an effect of the autotrophic denitrifying microorganism, a stream containing treated water and a part of the biomass flows out through an outflow port, and nitrogen gas produced through the denitrification reaction flows out upward; and a biomass recovery tank where the stream flows in, a membrane module is provided inside so that the treated water passing through the membrane module flows out, and the residual stream containing the biomass is returned to the biological reaction tank.

Description

TECHNICAL FIELD [0001] The present invention relates to a treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen,

The present invention relates to a system for treating wastewater containing ammonia nitrogen and nitrite nitrogen, and more particularly, to a system for treating wastewater containing ammonia nitrogen and nitrite nitrogen by reacting ammonia nitrogen with an electron donor and nitrite nitrogen with an electron acceptor under anaerobic conditions to produce nitrogen gas The present invention relates to a treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen using biomass including autotrophic denitrifying microorganisms.

Nitrogen components contained in various wastewaters cause eutrophication of the lake, and it is necessary to remove the nitrogen component because it causes a decrease in dissolved oxygen of the river. Major nitrogen components contained in the wastewater include ammonia nitrogen, nitrite nitrogen, nitrate nitrogen, organic nitrogen and the like.

Conventionally, wastewater containing a nitrogen component has been subjected to ion exchange treatment or oxidation by chlorine or ozone when the concentration of nitrogen is low. However, biological treatment is applied when the concentration is high. For example, ammonia nitrogen A method is known in which nitrite nitrogen or nitrate nitrogen is oxidized, an electron donor such as methanol is added, and nitrite nitrogen or nitrate nitrogen is reduced to nitrogen gas by denitrifying bacteria to remove nitrogen from the wastewater.

This method requires excess oxygen to oxidize the ammonia nitrogen to the nitrogen gas, which is a cause of high cost in terms of the energy required for wastewater treatment due to an excessive oxygen demand to supply the microorganisms. In addition, a cost for adding an organic substance such as methanol as an electron donor is required for the denitrification reaction, and since the denitrifying bacteria consumed and proliferated from such organic matter become surplus sludge, there arises a problem of waste disposal cost. In particular, since nitrate nitrogen is in an oxidation state compared to nitrite nitrogen, the oxygen supply cost is further increased, and furthermore, an electron donor is required to reduce it, and excess sludge generated also increases.

Thus, in recent years, a denitration method (see Reaction Scheme 1 below) using an autothermal denitrifying microorganism capable of reacting ammonia nitrogen as an electron donor and nitrite nitrogen as an electron acceptor to generate nitrogen gas under anaerobic conditions (Microbiology vol. 142, p2187-2196, 1996). This denitrification reaction is called anaerobic ammonium oxidation (ANAMMOX) reaction (hereinafter referred to as 'ANAMMOX reaction'), and the autotrophic denitrifying microorganism used is called ANAMMOX bacteria (hereinafter referred to as 'ANAMMOX bacteria'). . According to the denitrification method using the ANAMMOX reaction, the ammonia nitrogen can be oxidized using the oxidizing power of the nitrite nitrogen, so that the nitrogen can be removed with an oxygen consumption amount equivalent to the theoretical amount, and energy can be saved . In addition, since it is not necessary to add an organic matter such as methanol, the cost can be reduced, and the yield of the autotrophic microorganism is low and the amount of sludge generated is significantly smaller than that of the heterotrophic microorganism, have.

[Reaction Scheme 1]

ANAMMOX A method of passing a wastewater through an upflow column to a column packed with a carrier suitable for attachment of microorganisms such as sand, synthetic resin and gel in the form of a bioreactor and contacting the nitrogen compound with a microorganism on the carrier surface to carry out a denitrification reaction Can be applied. However, the proliferation rate of ANAMMOX bacteria is very slow to a maximum of about 0.065 / day, and it is known that it is considerably difficult to obtain a large amount of cells. On the other hand, since the amount of ANAMMOX bacteria present in the natural world is considerably small, it is necessary to sufficiently propagate the cells in order to start the denitrification apparatus using ANAMMOX bacteria. For this purpose, the ANAMMOX bacteria should be proliferated at the maximum growth rate in an ideal environment, It is necessary to keep the ANAMMOX bacteria efficiently in the system.

As described above, in order to proliferate ANAMMOX bacteria at the maximum rate, it is necessary to sufficiently supply a substance which becomes a substrate of cells such as ammonia nitrogen, nitrate nitrogen, inorganic carbon source, etc. However, And therefore, it is proliferated at a rate slower than the maximum growth rate, and its efficiency is also lowered. In order to permeate the substrate to the inner side of the biofilm, it is necessary to maintain the concentration of the substrate in the medium. However, when the nitrite nitrogen is present at a relatively high concentration, the ANAMMOX bacteria are inhibited, It is also said. In addition, when it is operated as an actual denitration apparatus, maneuver will be delayed in order to prevent the maximum load from being applied until the ANAMMOX bacteria grow sufficiently on the surface of the carrier. In order to solve this problem, it is also possible to put a carrier having a sufficient amount of ANAMMOX bacteria into the denitrification tank in advance. However, it is necessary to cultivate ANAMMOX bacteria in advance in a reaction vessel of the same size as the operated denitrification apparatus, And installation space is required, and the transportation cost of the cultured ANAMMOX bacteria is also increased. Furthermore, as a problem in propagating ANAMMOX bacteria on the surface of the carrier, some of the ANAMMOX bacteria on the surface of the carrier may always be stripped from the solution and may leak out into the treated water. That is, finally, the carrier surface is saturated with ANAMMOX bacteria. In order to balance the amount of ANAMMOX bacteria to be proliferated and the amount of ANAMMOX bacteria to be proliferated, the amount of the ANAMMOX bacteria is increased as the deposition amount of ANAMMOX bacteria increases, The increase rate of the denitrification ability becomes lower than the apparent maximum growth rate.

As shown in FIG. 1, a method of using the membrane separation method in which the membrane 11 is installed in the denitrification tank 10 is proposed in order to proliferate the ANAMMOX bacteria in a suspension state to the problems that occur when the ANAMMOX bacteria are grown using such carriers (Tao Wang et al., Bioresource Technology 122, 78-82, 2012). In this method, when the membrane separation means 11 having the hollow fiber membrane having the agitator 12 at the lower end and having a proper pore size is used, the holding power of the biomass is effectively enhanced To increase the rate of ANAMMOX bacterial growth by nearly two-fold. In such a membrane separation method, continuous filtration is performed while diffusing a suspended substance concentrated on the membrane surface by rotating an agitator provided at the bottom in order to prevent a fouling phenomenon occurring on the membrane surface, It is necessary to perform a cleaning operation in which the sludge attached to the film surface is peeled off periodically.

In such a cleaning operation, when the membrane separating means is taken out to the outside of the denitrifying tank, it leaks into the outside air, and the efficiency of the ANAMMOX reaction at the subsequent operation of the denitrifying vessel can not be lowered sharply. In addition, although backwashing operation in which sludge attached to the membrane surface is peeled off is taken into consideration, the contact with the outside air can not be completely avoided, so that the efficiency of the ANAMMOX reaction is lowered, There is also a disadvantage in terms of management such as stopping the operation of the city. In addition, only the use of an organic film made of a polymer material as a film material is considered, and the cleaning efficiency is low, so that the stop period of the reaction tank is increased, and problems such as cleaning cost and film durability are also raised.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a biomass including an autothermal denitrifying microorganism capable of producing nitrogen gas by reacting ammonia nitrogen with an electron donor and nitrite nitrogen with an electron acceptor under anaerobic conditions. In the treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen by using the method of the present invention, improvement of the biomass retention rate in the reactor and continuous infusion of nutrients are carried out, And to provide a treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen which can solve the problem of lowering the reactivity and lowering the reaction efficiency due to the stoppage of the reaction tank.

It is also intended to provide a treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen to which a material capable of solving the problems of deterioration of cleaning efficiency and durability deterioration due to the adoption of organic membranes as a conventional biomass recovery means.

The present invention also provides a treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen, which can be efficiently operated without adding any additional facilities in order to prevent aggregation of autotrophic denitrifying microorganisms in the reaction tank and to clean biomass recovery means I want to.

In order to solve the above-described problems, the present invention provides an ammonia-containing microorganism which comprises an autothermal denitrifying microorganism capable of producing nitrogen gas by reacting ammonia nitrogen with an electron donor and nitrite nitrogen with an electron acceptor under anaerobic conditions, 1. A treatment system for wastewater containing nitrogen and nitrite nitrogen, characterized in that the ammonia nitrogen and the wastewater containing nitrite nitrogen are introduced, denitrification is carried out by the action of the autotrophic denitrifying microorganism, A bioreactor in which a stream containing water and a portion of the biomass flows out and nitrogen gas generated by the denitrification reaction flows out upward; And a biomass recovery tank into which the stream is introduced and a membrane module is provided to discharge the treated water having passed through the membrane module and to return the residual stream containing the biomass to the bioreactor The present invention provides a system for treating wastewater containing ammonia nitrogen and nitrite nitrogen.

Also, the present invention provides a system for treating wastewater containing ammonia nitrogen and nitrite nitrogen, wherein the autotrophic denitrifying microorganism is anaerobic ammonium oxidation (ANAMMOX) bacteria.

The present invention also provides a system for treating wastewater containing ammonia nitrogen and nitrite nitrogen, wherein the membrane module is composed of a microfiltration membrane.

The present invention also provides a system for treating wastewater containing ammonia nitrogen and nitrite nitrogen, wherein the microfiltration membrane is made of a ceramic material.

The system may further include a nitrogen gas collecting part for collecting nitrogen gas flowing out to the upper part of the bioreactor and injecting a part of the nitrogen gas into the bioreactor, Wherein ammonia nitrogen and nitrite nitrogen are introduced into the waste water treatment system.

The present invention also provides a system for treating wastewater containing ammonia nitrogen and nitrite nitrogen, wherein a portion of the nitrogen gas is injected into the membrane module from the nitrogen gas collector.

The membrane modules are installed in parallel, and some of the nitrogen gas injected from the nitrogen gas collecting unit is selectively injected into only one module of the membrane module. The ammonia nitrogen and nitrite nitrogen- A processing system of the present invention.

According to the present invention, the autotrophic denitrifying microorganism is suspended in a bioreactor in which nutrients are continuously injected, so that the reaction can be performed. In addition, biomass recovery vessels are installed outside the bioreactor and biomass The waste water containing ammonia nitrogen and nitrite nitrogen which can prevent the problem of deterioration of reaction efficiency generated in the washing operation by installing the separation membrane in the conventional membrane separation method .

In addition, by adopting a ceramic filtration membrane as a biomass recovery means, it is possible to solve the problems of deterioration of cleaning efficiency and durability due to the adoption of conventional organic membranes, such as treatment of wastewater containing ammonia nitrogen and nitrite nitrogen System can be provided.

In addition, the nitrogen gas flowing out to the upper part of the bioreactor is recirculated and the gas is lifted through the air diffuser in the bioreactor to prevent flocculation of the autotrophic denitrifying microorganisms, It is possible to provide a treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen which can economically improve reaction efficiency while economically reusing reaction products.

In addition, since the cleaning mode using the recycled nitrogen gas is applied to only one membrane module by installing the membrane modules in parallel in the biomass recovery tank, the at least one membrane module always operates, It is possible to provide a treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen which need not be considered.

1 is a schematic view for explaining a treatment system of wastewater containing ammonia nitrogen and nitrite nitrogen using conventional membrane separation method,
2 is a schematic view for explaining a treatment system of wastewater containing ammonia nitrogen and nitrite nitrogen according to the first embodiment of the present invention,
3 is a schematic view for explaining a treatment system of wastewater containing ammonia nitrogen and nitrite nitrogen according to the second embodiment of the present invention,
4 is a schematic diagram illustrating a treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen according to the third embodiment of the present invention,
5 is a schematic diagram illustrating a system for treating wastewater containing ammonia nitrogen and nitrite nitrogen according to a fourth embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. In order to clearly illustrate the present invention, parts not related to the description are omitted, and like parts are denoted by similar reference numerals throughout the specification. Also, throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements, not excluding other elements, unless specifically stated otherwise.

First Embodiment

2 is a schematic diagram illustrating a treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen according to the first embodiment of the present invention.

Referring to FIG. 2, the system 100 for treating wastewater containing ammonia nitrogen and nitrite nitrogen according to the first embodiment of the present invention can treat ammonia nitrogen as an electron donor under anaerobic conditions, nitrite nitrogen as an electron acceptor And a nitrogen-containing denitrifying microorganism capable of reacting with ammonia nitrogen and nitrite nitrogen to produce ammonia nitrogen and nitrite nitrogen, wherein the ammonia nitrogen and nitrite nitrogen-containing waste water containing the ammonia nitrogen and the nitrite nitrogen The wastewater W is introduced and the denitrification reaction is performed by the action of the autotrophic denitrifying microorganism, and the treated water and the stream S1 containing the biomass fraction are discharged through the outlet 111, A biological reaction tank 110 in which the generated nitrogen gas flows upward; And a membrane module 121 is installed in the interior of the membrane module 121 to discharge the treated water S2 having passed through the membrane module 121. The residual stream S3 containing the biomass And a biomass recovery vessel (120) for returning the biomass to the bioreactor (110).

In the wastewater treatment system 100 according to the present invention, the raw water is wastewater W containing ammonia nitrogen and nitrite nitrogen and is treated as the for-treatment water and is continuously supplied to the bioreactor 110).

The raw water W may contain organic substances other than ammonia nitrogen and nitrite nitrogen, or organic nitrogen, but they are preferably decomposed to such an extent as to become ammonia nitrogen in advance before the denitrification treatment. In addition, It is preferable to remove dissolved oxygen as necessary.

When denitrification is carried out using ANAMMOX bacteria as the autotrophic denitrifying microorganism, the ratio of the nitrite nitrogen (ammonia nitrogen: nitrite nitrogen, molar ratio) to the ammonia nitrogen of the raw water W is 0.5 to 2, May be 1 to 1.5, more preferably 1 to 1.3. Therefore, when raw water containing ammonia nitrogen is treated, nitrite type nitrification is performed on a part of the raw water to mix raw water containing ammonia nitrogen and nitrite containing nitrite nitrogen to make raw water, It is preferable to use a solution obtained by nitrification of a part of the ammonia nitrogen in the raw water.

Generally, wastewater containing ammonia nitrogen, organic nitrogen, organic matter, etc., such as sewage, manure, onion digestion liquor, factory wastewater, and landfill leachate is often treated, but in this case, Decomposing the organic nitrogen into ammonia nitrogen, or subjecting the organic nitrogen to partial nitrification may be used as the raw water.

In the bioreactor 110, the raw water W is introduced and the ammonia nitrogen and the nitrite nitrogen contained in the raw water W are simultaneously denitrified by the autotrophic denitrifying microorganisms contained in the biomass in the bioreactor 110. The autotrophic denitrifying microorganism may be an ANAMMOX bacterium using an inorganic carbon source such as carbon dioxide, carbonate or the like, and is not particularly limited as long as the bacterium is capable of performing the reaction according to the reaction formula 1, for example, Planctomycetes, . ≪ / RTI >

The bioreactor 110 is hermetically sealed to prevent external air from being mixed therein. The nitrogen gas generated from the denitrification reaction is discharged to the outside through the check valve 112 to prevent air from flowing back from the outside.

Means for preventing the aggregation of the autotrophic denitrifying microorganisms in the bioreactor 110 in the present invention can be considered. That is, in order to prevent the denitrifying microorganisms from being agglomerated and immersed in the bioreactor 110 to reduce the reactivity due to the reduction of the contact area with the substrate, an agitator 113 or an underwater pump or a gas lifting device is installed under the reaction tank, It is possible to prevent microbial agglomeration and to disperse around the middle of the reaction tank 110. Preferably, the nitrogen gas discharged from the upper part of the reaction tank 110 is recycled and used for prevention of flocculation, which will be described in detail in the following second embodiment.

The raw water W processed in the bioreactor 110 flows into the biomass recovery tank 120 through the outlet 111 into the stream S1 containing a part of the biomass and is stored in the biomass recovery tank 120 The treated water S2 having passed through the membrane module 121 is discharged through the pump P2 and the residual stream S3 containing the biomass is returned to the bioreactor 110 through the return pump P3 .

In the present invention, it is preferable that a microfiltration membrane is used in the membrane module 121 in order to significantly prevent the outflow of ANAMMOX bacteria through the effluent S2. The material of the membrane module 121 may be a polymer organic material such as polyethylene or polypropylene, or an inorganic material such as ceramics or metal. However, in order to prevent membrane contamination due to irreversible bio-contamination and to reduce the maintenance cost, It is preferable to use a membrane module 121 made of a ceramic material. The membrane module 121 may have various shapes such as a hollow fiber membrane, a tubular membrane, and a flat membrane, and may be installed in the form of a hollow fiber membrane. Various methods such as a dead end filtration method, a cross flow filtration method, an immersion membrane method, and a dynamic filtration method can be applied to the separation method by the membrane module 121, It is desirable to use a cross flow method in consideration of this.

In the system 100 according to the first embodiment of the present invention, since the stream valve 122 and the biomass transport valve 123 are shut off during the cleaning of the membrane module 121, 0.0 > ANAMMOX < / RTI > bacteria in contact with the outside. In this case, a well-known method can be applied to the cleaning of the membrane module 121. For example, an alkali solution such as sodium hydroxide solution, an oxidizing agent such as sodium hypochlorite or hydrogen peroxide, an acid such as hydrochloric acid, sulfuric acid, citric acid, and a variety of surfactants may be used.

Second Embodiment

3 is a schematic diagram illustrating a treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen according to a second embodiment of the present invention.

Referring to FIG. 3, a treatment system 200 for treating wastewater containing ammonia nitrogen and nitrite nitrogen according to a second embodiment of the present invention can treat ammonia nitrogen as an electron donor under anaerobic conditions, nitrite nitrogen as an electron acceptor And a nitrogen-containing denitrifying microorganism capable of reacting with ammonia nitrogen and nitrite nitrogen to produce ammonia nitrogen and nitrite nitrogen, wherein the ammonia nitrogen and nitrite nitrogen-containing waste water containing the ammonia nitrogen and the nitrite nitrogen The wastewater W is introduced and the denitrification reaction is carried out by the action of the autotrophic denitrifying microorganism and the treated water and the stream S1 containing the biomass fraction are discharged through the outlet 211, A bioreactor 210 in which the generated nitrogen gas flows upward; The stream S1 flows in and a membrane module 221 is installed therein to drain the treated water S2 that has passed through the membrane module 221. The residual stream S3 containing the biomass A biomass recovery tank 220 for returning the biomass to the bioreactor 210; And a nitrogen gas collecting unit 230 collecting the nitrogen gas flowing out to the upper part of the bioreactor 210 and injecting a part of the nitrogen gas into the bioreactor 210, And an acid generator 240 for raising the injected nitrogen gas. Hereinafter, a configuration different from the first embodiment will be mainly described.

The system 200 for treating wastewater containing ammonia nitrogen and nitrite nitrogen according to the second embodiment of the present invention does not discharge the nitrogen gas generated from the bioreactor 210 to the outside of the system unlike the first embodiment And recycles it as a means for preventing the denitrifying microorganisms from aggregating in the bioreactor 210 by recirculating it to the bioreactor 210.

The nitrogen gas generated in the bioreactor 210 is compressed by the nitrogen gas trapping unit 230 through the exhaust port 213 and transferred to the oxidizer unit 240 installed in the lower part of the biological reactor 210, The biomass including the denitrifying microorganisms in the bioreactor 210 is induced and the contact area of the denitrifying microorganisms with the substrate is maximized around the middle part of the bioreactor 210, And the power ratio can be reduced because no additional equipment such as mechanical stirring is required. In this case, when the partial pressure of the nitrogen gas in the bioreactor 210 is excessive, a gas lifting effect can not be exerted on the load of the anaerosis device 240. Therefore, a check valve 212 is provided on the bioreactor 210, The nitrogen gas may be exhausted to the outside of the system so that the partial pressure is lower than the predetermined partial pressure through the check valve 212.

Third Embodiment

4 is a schematic diagram illustrating a treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen according to a third embodiment of the present invention.

Referring to FIG. 4, a system 300 for treating wastewater containing ammonia nitrogen and nitrite nitrogen according to the third embodiment of the present invention is characterized in that ammonia nitrogen is used as an electron donor in an anoxic condition, nitrite nitrogen is used as an electron acceptor And a nitrogen-containing denitrifying microorganism capable of reacting with ammonia nitrogen and nitrite nitrogen to produce ammonia nitrogen and nitrite nitrogen, wherein the ammonia nitrogen and nitrite nitrogen-containing waste water containing the ammonia nitrogen and the nitrite nitrogen The wastewater W is introduced and the denitrification reaction is performed by the action of the autotrophic denitrifying microorganism, and the treated water and the stream S1 containing the biomass fraction are discharged through the outlet 311, A biological reaction tank (310) in which the generated nitrogen gas flows upward; The stream S1 flows in and a membrane module 321 is installed to discharge the treated water S2 having passed through the membrane module 321. The residual stream S3 containing the biomass A biomass recovery tank 320 for returning the biomass to the bioreactor 310; And a nitrogen gas collecting part (330) collecting nitrogen gas flowing out to the upper part of the bioreactor (310) and injecting a part of the nitrogen gas into the bioreactor (310). The bioreactor (310) And a diffuser 333 for increasing the injected nitrogen gas. A portion of the nitrogen gas from the nitrogen gas collector 330 is injected into the membrane module 321. Hereinafter, a configuration different from the second embodiment will be mainly described.

The treatment system 300 for treating wastewater containing ammonia nitrogen and nitrite nitrogen according to the third embodiment of the present invention can be applied to a biomass recovery tank 300 in which the application range of nitrogen gas reused in the bioreactor 310 in the second embodiment, (320). That is, when the membrane module 321 in the biomass recovery tank 320 is cleaned, a part S4 of the nitrogen gas compressed in the nitrogen gas trapping unit 330 is transferred to the membrane module 321 and is backwashed So that the cleaning operation can be performed. If the partial pressure of the nitrogen gas in the biomass recovery tank 320 is excessive, it is difficult to carry out the backwashing process. Therefore, the check valve 324 is installed on the biomass recovery tank 320, It is possible to discharge a part of the nitrogen gas to the outside of the system by making the pressure lower than the predetermined partial pressure through the valve 324.

Fourth Embodiment

5 is a schematic diagram illustrating a treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen according to a fourth embodiment of the present invention.

Referring to FIG. 5, a system 400 for treating wastewater containing ammonia nitrogen and nitrite nitrogen according to a fourth embodiment of the present invention includes an ammonia nitrogen as an electron donor in an anoxic condition, a nitrite nitrogen as an electron acceptor And a nitrogen-containing denitrifying microorganism capable of reacting with ammonia nitrogen and nitrite nitrogen to produce ammonia nitrogen and nitrite nitrogen, wherein the ammonia nitrogen and nitrite nitrogen-containing waste water containing the ammonia nitrogen and the nitrite nitrogen The wastewater W is introduced and the denitrification reaction is performed by the action of the autotrophic denitrifying microorganism, and the treated water and the stream S1 containing the biomass fraction are discharged through the outlet 411, A biological reaction tank 410 through which the generated nitrogen gas flows upward; The stream S1 flows in and a membrane module 421 is installed to discharge the treated water S2 having passed through the membrane module 421. The residual stream S3 containing the biomass A biomass recovery tank 420 for returning the biomass to the bioreactor 410; And a nitrogen gas collecting unit 430 collecting nitrogen gas flowing out to the upper part of the bioreactor 410 and injecting a part of the nitrogen gas into the bioreactor 410, A nitrogen gas is supplied from the nitrogen gas collecting unit 430 to the membrane module 421 and the membrane module 421 is connected in parallel with the nitrogen gas collecting unit 430. [ And some nitrogen gas injected from the nitrogen gas collecting part 430 is selectively injected into only one of the modules 421 of the membrane module 421. Hereinafter, a configuration different from the third embodiment will be mainly described.

The system 400 for treating wastewater containing ammonia nitrogen and nitrite nitrogen according to the fourth embodiment of the present invention is configured such that the nitrogen gas from the nitrogen gas collector during the membrane module washing process in the biomass recovery tank according to the third embodiment The membrane module 421 is installed in parallel so that the membrane module 421 in the biomass recovery tank 420 can be washed alternately. In this case, So that it is possible to continuously operate without interruption of the entire process, thereby improving the material circulation rate in the biomass recovery vessel 420.

Specifically, when the first injection valve 425a is shut off and the second injection valve 425b is opened so that the nitrogen gas flow S4 from the nitrogen gas trap 430 is only injected into the second membrane module 421b, The first membrane module 421a operates in the biomass concentration mode to maintain the treatment process and the second membrane module 421b operates in the backwash mode to perform the cleaning process using the injected nitrogen gas. At this time, the second outflow valve 426b is shut off, and only the first outflow valve 426a is opened so that only the treated water S2 that has passed through the first membrane module 421a flows out. When the first membrane module 421a is to be cleaned as needed after the cleaning process of the second membrane module 421b is completed, the second injection valve 425b is shut off and the first injection valve 425a is closed The first outlet valve 426a is closed and only the second outlet valve 426b is opened so that the cleaning process is alternately performed.

The preferred embodiments of the present invention have been described in detail with reference to the drawings. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.

Accordingly, the scope of the present invention is defined by the appended claims rather than the foregoing detailed description, and all changes or modifications derived from the meaning, range, and equivalence of the claims are included in the scope of the present invention Should be interpreted.

100, 200, 300, 400: Wastewater treatment system
110, 210, 310, 410:
111, 211, 311, 411: Bioreactor outlet
112, 212: Bioreactor check valve 113: Stirrer
120, 220, 320, 420: Biomass recovery tank
121, 221, 321, 421: Membrane module 122: Stream valve
123: Biomass conveying valve 213: Nitrogen gas vent
230, 330, 430: Nitrogen gas collecting units 240, 340, 440:
324: Biomass recovery tank check valve 421a: First membrane module
421b: second membrane module 425a: first injection valve
425b: second injection valve 426a: first outlet valve
426b: second outflow valve W: waste water (raw water)
S1: Bioreactor effluent stream S2: Biomass recovery tank treated water
S3: Residual (conveyed) stream S4: Nitrogen gas for backwash
P1: waste water (raw water) Pump P2: treated water pump
P3: Return pump

Claims (7)

Ammonia nitrogen and nitrite nitrogen-containing wastewater using biomass including an autotrophic denitrifying microorganism capable of producing nitrogen gas by reacting ammonia nitrogen with an electron donor and nitrite nitrogen with an electron acceptor under anaerobic conditions A processing system comprising:
The ammonia nitrogen and the nitrite-nitrogen-containing wastewater are introduced, the denitrification reaction is performed by the action of the autotrophic denitrifying microorganism, the treated water and the stream containing the biomass fraction are discharged through the outlet, A bioreactor in which nitrogen gas generated by a denitrification reaction flows upward; And
A biomass recovery tank into which the stream flows, a membrane module disposed therein, for discharging treated water having passed through the membrane module, and returning the residual stream containing the biomass to the bioreactor;
Characterized in that the ammonia nitrogen and the nitrite nitrogen are present in the treated water. The method according to claim 1,
Wherein the autotrophic denitrifying microorganism is an anaerobic ammonium oxidation (ANAMMOX) bacterium. The system for treating wastewater containing ammonia nitrogen and nitrite nitrogen. The method according to claim 1,
Wherein the membrane module is comprised of a microfiltration membrane. ≪ RTI ID = 0.0 > 8. < / RTI > The method of claim 3,
Wherein the microfiltration membrane is made of a ceramic material. The system for treating wastewater containing ammonia nitrogen and nitrite nitrogen. The method according to claim 1,
The system comprises:
Further comprising: a nitrogen gas collecting unit collecting nitrogen gas flowing out to an upper part of the bioreactor and injecting a part of the nitrogen gas into the bioreactor,
Wherein the bioreactor is provided with an aeration device for raising the injected nitrogen gas in a lower part thereof. 2. A treatment system for wastewater containing ammonia nitrogen and nitrite nitrogen. 6. The method of claim 5,
Wherein a portion of the nitrogen gas from the nitrogen gas collecting portion is injected into the membrane module. The method according to claim 6,
Wherein the membrane module is installed in parallel and the nitrogen gas injected from the nitrogen gas collecting part is selectively injected into only one of the modules of the membrane module to treat the wastewater containing ammonia nitrogen and nitrite nitrogen system.

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