WO2014129759A1

WO2014129759A1 - Wastewater treatment device using separation membrane with which recovery of granules of active microorganisms is possible and method for treating wastewater using same

Info

Publication number: WO2014129759A1
Application number: PCT/KR2014/000978
Authority: WO
Inventors: 유대환; 정민기; 송철우
Original assignee: 주식회사 부강테크
Priority date: 2013-02-20
Filing date: 2014-02-05
Publication date: 2014-08-28
Also published as: KR20140104627A

Abstract

Provided are device and method for treating sewage and wastewater, with which recovery of granules of active microorganisms is maximized and a stable quality of treated water is obtained. In a granule recovery vessel, granules of microorganisms exhibiting high activity and non-active solid substances are rapidly separated, and the granules are returned to a reaction vessel in order to secure a high concentration of granules in the process. Non-precipitated inactive solid substances are made to flow into a separation vessel and subjected to filtration in order to obtain excellent treated water. The organism reaction vessel is constituted by an anoxic vessel, an anaerobic vessel and an aerobic vessel, and removes nitrogen and phosphorous in the sewage. Granules of heterotrophic microorganisms are recovered from inactive solid substances and treated water in a granule recovery vessel (1) and returned to a stage prior to the anoxic vessel. The inactive solid substances separated from the heterotrophic microorganisms and treated water are sent to the aerobic vessel. Granules of autotrophic microorganisms are recovered in a granule recovery vessel (2) which is a post-stage of the aerobic vessel and returned to a stage prior to the aerobic vessel. The separated inactive solid substances and treated water are sent to a separation membrane vessel, and the inactive solid substances and treated water are separated in the separation membrane vessel.

Description

Wastewater treatment device capable of recovering active microbial granules using a membrane and wastewater treatment method using the same

The present invention relates to a wastewater treatment apparatus capable of recovering active microbial granules using a separator and a wastewater treatment method using the same, and more particularly, to a separator. Highly active granules can be effectively recovered and maintained in the process, and inert solids are selectively separated / condensed using a membrane and discharged out of the process.The reactor maintains high activity and inert solids are quickly discharged out of the process to discharge wastewater. An apparatus and method for efficiently processing in a short time.

Biological wastewater treatment processes are achieved by keeping microorganisms active in the process while contacting the microorganisms and contaminants in the reactor and maintaining the time and conditions under which the reactions necessary for the microorganisms to degrade the contaminants can occur. Thus, the rate of treatment of pollutants is determined by how much active microorganisms are present in the process. In order to secure a large number of microorganisms in the process, a general biological treatment process is provided with a sedimentation basin for separating microorganisms and treated water at the rear of the reactor as shown in FIG. 1. Unlike the reaction tank, the sedimentation basin is designed and operated so that disturbance does not occur, and serves to maintain the high concentration of microorganisms in the reaction tank by inducing the separation of the microorganism and the treated water and returning the separated microorganism into the process.

Microorganisms used in biological treatment process are very diverse, but they are divided into heterotrophic microorganisms and autotrophic microorganisms according to the carbon source used, and these microorganisms are separated / concentrated in the sedimentation basin because their specific gravity is about 1.1 ~ 1.2. There is a limit of the concentration of microorganisms that can be. In general, the concentration of microorganisms that can be separated / concentrated by sedimentation in sedimentation basin of wastewater treatment process is known to be less than about 5,000 mg / L. In order to ensure the volume of the reactor must be increased. Since the increase in the volume of the reactor is accompanied by an increase in the construction cost, efforts have been made to achieve high treatment efficiency while maximizing the active microorganism and reducing the size of the reactor.

One way to achieve this goal is to utilize microbial granules, which are granular sludges in which microorganisms are fixed at high concentrations, which are produced by agglomeration of cells without external media, and are distinguished from biofilms. It is formed through the self-immobilization of microbial flocs under certain conditions during sewage and can be divided into aerobic and anaerobic granules. Microbial granules are dense microbial colonies containing millions of active microorganisms per gram and contain various bacterial species in the population. The shape and size of the microbial granules vary depending on the operating conditions, and generally shows a smooth surface shape with a particle size range of 0.2-7 mm (see FIG. 2). Therefore, it can be clearly distinguished from sludge floc (floc) with the naked eye, and has a good sedimentation characteristic because it has a uniform and dense rigid structure compared to the floc state. SVI (Sludge Volume Index: index of sedimentation capacity) refers to the capacity indicator of sludge, and the volume (mL) occupied by 1 g of sludge after standing for 30 minutes after mixing the mixed liquid in the aeration tank of activated sludge with a 1,000 mL volume cylinder. The sludge from the treatment process is 80-120 mL / g and the SVI of the microbial granules is 80 mL / g. Therefore, the solid-liquid separation can be easily prevented sedimentation problems, such as sludge injuries, it is possible to reduce the settling time and volume of the sedimentation basin. Therefore, it is possible to maintain a high concentration in the process can reduce the volume of the reactor can reduce the site or cost. In addition, since the microbial cells are agglomerated at a high density and protected by an Extracelluar Polymeric Substance (EPS) matrix, they are highly resistant to external impact loads and toxic substances. In addition, it has an adsorption function on the EPS surface to remove heavy metals. In addition, since there is no separate carrier, there is no problem of microbial detachment.

(Patent Document 1) KR 100513352 B1

The prior art patent registration (KR 100513352 B1) regarding a wastewater treatment apparatus using anaerobic granule sludge is for a wastewater treatment apparatus in which a biological treatment tank in which a membrane is immersed and a reaction tank filled with anaerobic granule sludge is combined. Separately, an ABR (Anaerobic Baffled Reactor) or UASB (Upflow Anaerobic Sludge Blanket) reactor filled with anaerobic granule sludge is installed, and the biological treatment tank of the shear is maintained in order to maintain the activity of the anaerobic granule sludge in the reactor and to prevent excessive growth of the biofilm in the reactor. By dipping the membrane, the treated water was extracted through the membrane, and the extracted treated water was injected into the reactor to remove organic matter and nitrogen from the wastewater containing high concentration of nitrogen.

(Patent Document 2) KR 1020120089495 A

On the other hand, Korean Patent Application Publication (KR 1020120089495 A), which is a related art for wastewater treatment apparatus using aerobic granule sludge, relates to a wastewater treatment apparatus and method using biofilm and aerobic granule sludge, and introduces aerobic granule sludge to the upper part of the reactor. Nitrification and denitrification were performed by the sludge clusters present in each layer in the granule sludge, and the high sedimentability of the granulated sludge enables solid-liquid separation within a short time and stably removes the organic matter even when an instantaneous organic impact load occurs.

Nitrifying microorganisms, denitrifying microorganisms, Phosphate Accumulating Organisms (PAO), denitirifying Phosphate Accumulating Organisms (dPAO), Glcogen Accumulating Organisms (GAO), etc. Granulation is possible in most microbial populations and therefore can be applied to any contaminant treatment.

However, there is a fatal problem in applying granules to actual wastewater treatment. This problem is due to the characteristics of the waste water is configured in various ways as shown in FIG. In other words, if only dissolved dissolved substances (SCOD: Soluble chemical oxygen demand, SCOD = S _I + S _S , S _I : Soluble inert COD, S _S : Readily biodegradable COD) are present in the process, In reality, there is a large amount of particulate matter (XCOD = X _I + X _S , X _I : Inert suspended organic matter, X _S : Slowly inert COD) in the waste water. Impossible volatile solids (X _I = NBDVSS), non-volatile solids (FSS: Fixed Suspended Solids) are mixed together and present (FSS + TCOD) (Biodegradable organics)). The various types of solids are mixed, called mixed liquor suspended solids (MLSS), but it is technically very difficult to selectively recover only active microorganisms from the mixed liquor suspended solids.

In the case of microbial granules, sedimentation is superior to that of ordinary suspended solids, and thus, separation and recovery with other solids are possible using the difference in sedimentation. Therefore, when the actual wastewater is treated using the microbial granules, other solids except the microbial granules do not settle properly and flow out together with the treated water, and as a result, the treated water quality deteriorates and it is impossible to comply with the water quality standards. Therefore, it is practically difficult to apply microbial granules to treat actual wastewater in which various types of solids are present.

The technical problem to be achieved by the present invention is to simultaneously achieve the goal of recovering the microbial granules and securing a stable treated water quality by using a membrane in treating the actual waste water by using the active microbial granules.

Wastewater treatment apparatus according to the present invention for achieving the above technical problem, the bioreactor, the microbial granules and the granules recovery tank for separating the inert solids, and the inert solids and the treated water separating the microbial granules growth and decomposition of contaminants It characterized in that it comprises a separation membrane bath.

Preferably, the wastewater treatment apparatus further includes a concentrated separation membrane tank for concentrating the inert solid separated from the separation tank through a separate separation membrane.

The bioreactor is preferably configured in the order of anaerobic tank, anaerobic tank, aerobic tank to remove nitrogen and phosphorus.

The granule recovery tank is divided into granule recovery tank 1 and granule recovery tank 2, granule recovery of the heterotrophic microorganisms in the granule recovery tank 1 is returned to the front end of the anaerobic tank, granules of independent nutrient microorganisms in the granule recovery tank 2 It is recovered and returned to the front end of the aerobic tank.

Wastewater treatment apparatus according to the present invention, the microbial granules and inert solids are quickly separated using the settling rate difference, granules are returned to the process and the inert solids which do not precipitate are separated / condensed using a separator to provide stable treated water quality. The volume reduction of secured and disposed sludge can be achieved simultaneously.

According to another aspect of the invention, (a) introducing waste water into the bioreactor to induce the growth of microbial granules and to decompose contaminants; (b) recovering the microbial granules from inert solids and treated water in a granule recovery tank installed at the rear of the bioreactor and returning them to the front of the bioreactor; (c) transferring the inert solid and the treated water separated from the microbial granule in the granule recovery tank to the separation membrane tank; And (d) separating the inert solids and the treated water in the separation membrane tank.

In addition, (a) introducing wastewater into the bioreactor consisting of anaerobic tank, anaerobic tank and aerobic tank to induce growth of microbial granules and decompose contaminants; (b) recovering the microbial granules from the inert solid and the treated water in the granule recovery tank installed at the rear end of the aerobic tank and returning them to the front end of the anaerobic tank; (c) transferring the inert solid and the treated water separated from the microbial granule in the granule recovery tank to the separation membrane tank; And (d) separating the inert solids and the treated water in the separation membrane tank.

In addition, (a) introducing the waste water into the bioreactor consisting of anaerobic tank, anaerobic tank, granule recovery tank 1, aerobic tank and granule recovery tank 2 in the rear end of the aerobic tank to induce growth of microbial granules and decompose contaminants; (b) recovering the granules of heterotrophic microorganisms from the inert solids and the treated water in the granule recovery tank 1 and returning them to the front end of the anaerobic tank and transferring the inert solids and the treated water separated from the heterotrophic granules to the aerobic tank. step; (c) recovering granules of autotrophic microorganisms from the granule recovery tank 2 at the rear end of the aerobic tank and returning them to the front end of the aerobic tank; (d) transferring the inert solid and the treated water separated from the granules of the autotrophic microorganism in the granule recovery tank 2 to the separation membrane tank; And (e) there is provided a waste water treatment method comprising the step of separating the inert solid and the treated water in the separation membrane.

Such wastewater treatment methods may further include the step of concentrating the inert solid separated in the separation membrane tank through the separation membrane in a separate concentration membrane tank.

According to the present invention, a high concentration of microorganism granules in the process can be selectively dominated, and inert solids without contaminant purification ability can be selectively separated / discharged to maximize the activity of the reactor. In addition, in the case of the separator, since the load of solids is reduced compared to a general separator process, the permeation rate is maintained to be high, so that a large amount of water can be separated even with a small separator, thereby reducing the installation cost of the separator. In addition, since only the inorganic solids are selectively separated, the phenomenon in which the membrane is clogged due to the growth of microorganisms can be reduced, thereby making it easy to maintain and reduce the chemicals required for cleaning the membrane. Therefore, in the treatment of the actual waste water, the size of the reactor can be reduced by maximizing the microbial activity of the reactor, maintaining the high permeation rate, the installation cost of the membrane is reduced, and as a result, the overall initial investment cost is lowered, and the maintenance of the membrane becomes easier. The total cost of operation can be reduced by reducing the management cost and reducing the amount of sludge generated. In addition, untreated precipitated solids can be reliably filtered to obtain a stable treated water.

1 is a conceptual diagram of a conventional wastewater treatment process.

2 is a photograph showing a general granule generated in the sewage treatment.

3 is a conceptual diagram relating to the properties of various substances contained in waste water.

4 is a conceptual diagram of a wastewater treatment apparatus to which a granule recovery tank and a separator are applied according to the present invention.

5 is a conceptual diagram of a bioreactor according to the present invention divided into an anaerobic tank, an anaerobic tank, an aerobic tank and a granule recovery tank.

6 is a conceptual diagram divided into a bioreactor according to the present invention anaerobic tank, anaerobic, granule recovery tank 1, aerobic tank and granule recovery tank 2.

The present invention proposes a new process for further increasing the treatment efficiency while improving the conventional water treatment process for increasing the treatment efficiency of waste water. In order to achieve this, the granules are applied to efficiently treat the wastewater containing various contaminants and the membrane filtration process. Minimize the concentration of Mixed Liquor Suspended Solids (MLSS) of influent flowing into the membrane filtration process by constructing bioreactors, anaerobic tanks, anaerobic tanks, and aerobic tanks using granules in front of the membrane process to minimize membrane contamination. By maintaining the concentration of microorganisms in the bioreactor to more than 20,000mg / L, it is possible to maximize the treatment of organic matter and nutrients, and to minimize the land area.

Wastewater treatment apparatus of the present invention, characterized in that it comprises a bioreactor in which growth of microbial granules and decomposition of contaminants occurs, a granule recovery tank for separating microbial granules and inert solids, and a separation membrane tank for separating inert solids and treated water. It is done. The bioreactor may be configured in the order of anaerobic tank, anaerobic tank, aerobic tank to remove nitrogen and phosphorus. In addition, the granule recovery tank is divided into granule recovery tank 1 and granule recovery tank 2, and in the granule recovery tank 1, the granules of heterotrophic microorganisms are recovered and returned to the front end of the anaerobic tank. It is recovered and returned to the front end of the aerobic tank.

Method for treating wastewater according to the first embodiment of the present invention, (a) introducing the wastewater into the bioreactor to induce the growth of microbial granules and to decompose contaminants; (b) recovering the microbial granules from inert solids and treated water in a granule recovery tank installed at the rear of the bioreactor and returning them to the front of the bioreactor; (c) transferring the inert solid and the treated water separated from the microbial granule in the granule recovery tank to the separation membrane tank; And (d) separating the inert solid and the treated water in the separation tank.

Method for treating wastewater according to another embodiment of the present invention, (a) introducing the wastewater into a bioreactor consisting of an anaerobic tank, an anaerobic tank and an aerobic tank to induce growth of microbial granules and decompose contaminants; (b) recovering the microbial granules from the inert solid and the treated water in the granule recovery tank installed at the rear end of the aerobic tank and returning them to the front end of the anaerobic tank; (c) transferring the inert solid and the treated water separated from the microbial granule in the granule recovery tank to the separation membrane tank; And (d) separating the inert solid and the treated water in the separation tank.

Waste water treatment method according to another embodiment of the present invention, (a) the waste water is introduced into the bioreactor consisting of anaerobic tank, anaerobic tank, granule recovery tank 1, aerobic tank and granule recovery tank 2 in the aerobic tank rear end to grow the microbial granules Inducing and decomposing contaminants; (b) recovering the granules of heterotrophic microorganisms from the inert solids and the treated water in the granule recovery tank 1 and returning them to the front end of the anaerobic tank and transferring the inert solids and the treated water separated from the heterotrophic granules to the aerobic tank. step; (c) recovering granules of autotrophic microorganisms from the granule recovery tank 2 at the rear end of the aerobic tank and returning them to the front end of the aerobic tank; (d) transferring the inert solid and the treated water separated from the granules of the autotrophic microorganism in the granule recovery tank 2 to the separation membrane tank; And (e) separating the inert solid and the treated water in the separation tank.

Each such wastewater treatment method may further include the step of concentrating the inert solid separated in the separation membrane tank through the separation membrane in a separate concentration membrane tank.

Hereinafter, some embodiments will be described in detail to specifically describe the present invention. However, embodiments according to the present invention may be modified in many different forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. The embodiments of the present invention are provided to more easily explain the present invention to those skilled in the art.

In the present invention, the process is configured as shown in FIG. 4, the present invention is composed of a bioreactor, granule recovery tank, separation membrane tank, concentrated separation membrane tank.

When wastewater enters the bioreactor, the biodegradable contaminants are degraded through biological reaction by granules in the reactor, whereby additional granules are formed. The reactor is subjected to organic matter oxidation, nitrogen oxidation, nitrogen removal through denitrification and phosphorus removal according to given conditions. In the biological treatment process performed in the bioreactor, the concentration of activated sludge is maintained at 20,000 mg / L or more to maximize the treatment of organic matter by the microorganism, nitrification, and denitrification. The decomposed waste water is introduced into the granule recovery tank at the end of the reactor. Granules recovery tanks separate granules and inert solids in a short residence time. Granules, which have settled quickly due to good sedimentation, are returned to the front end of the bioreactor using a pump. Inert solids that do not precipitate are introduced into the separation membrane and filtered through a separation membrane having a nominal pore size of 0.001 to 0.4 μm to separate the treated water and the solids. The treated water is discharged and the separated inert solids are introduced into the concentrated membrane bath and finally concentrated out of the process.

There are various pollutants in the waste water, and the reaction conditions for removing them are various and the anaerobic tank, anoxic tank, and aerobic tank can be appropriately configured to remove the pollutants effectively.

Figure 5 applies the granule recovery and membrane technology of the present invention in a process for removing nitrogen and phosphorus. It is composed of an anaerobic tank for removing phosphorus, an anaerobic tank for removing nitrogen through denitrification, and an aerobic tank for oxidizing ammonia nitrogen. After passing through the first membrane tank, the internal transport to return the nitrate nitrogen required for denitrification is carried out by an anoxic tank shear.

Influent wastewater is first treated with phosphorus-removing microorganisms in anaerobic tanks (Phase-removing aerobic microorganisms (PAOs) for aerobacter, Alcaligenes, Bacillus, Brevibacterium, Flavobacterium ( Flavobacterium, Lactobacillus, Micrococcus, etc. are preferred), and the main functions of elution of phosphorus in wastewater introduced from the outside, intake and storage of organic matter. In this case, phosphorous elution is performed while releasing poly-phosphate accumulated in microbial cells in the mixed solution in the form of ortho-phosphate. In the case of organic intake and storage, the organics in the mixture are taken into the cells. Ingested organics are dehydrogenating Phosphorous Removing Bacteria (PHA), which is stored in cells as PHA (Poly Hydroxy Alkanoate), which is mainly composed of glycogen and Poly Hydroxy Butyrate (PHB), which can be stored in cells or ingested at the anaerobic stage. By using microorganisms, etc.), phosphorus is biologically removed even in a low oxygen demand (COD) environment. In the anaerobic tank, a stirrer may be installed to sufficiently mix the phosphorus removing microorganism and the waste water. Thereafter, denitrification reaction occurs in which annitrogen is removed from nitrogen, and denitrification by microorganism granules occurs by using organic substances present in the incoming wastewater as electron acceptors, and organic substances are simultaneously removed in this process. If denitrification is not sufficiently performed in an oxygen-free tank, the denitrification efficiency may be increased by artificially injecting an external organic carbon source.

The treated water then undergoes an aerobic process for oxidizing ammoniacal nitrogen. In the aerobic tank, the ammonia nitrogen contained in the treated water is nitrified to nitrate nitrogen, and organic matter not removed in the anoxic tank is oxidized and converted into carbon dioxide. The decomposed waste water is introduced into the granule recovery tank at the end of the reactor.

Granules recovery tanks separate granules and inert solids in a short residence time. Granules that have settled quickly due to good sedimentation are returned to the anaerobic shear using a pump. Inert solids that do not precipitate are introduced into the membrane bath and treated water and solids are separated through a membrane having a nominal pore size of 0.001 to 0.4 μm. The treated water is discharged and the separated inert solid is introduced into the concentrated membrane tank, concentrated and finally discharged out of the process, and the internal conveyance for conveying the nitrate nitrogen necessary for denitrification is performed at the front end of the anoxic tank.

6 is a process for removing nitrogen and phosphorus, but the same purpose as in FIG. Configure. Heterotrophic microorganisms (as heterotrophic anaerobic microorganisms, methane-producing bacteria (eg, Methanosarcina genus, Methanothrix genus, Methanobacterium genus, Methnobrevibacter) Genus, Sulfate Reducing Bacteria- For example, Genus Desulfovibrio, Genus Desulfotomaculum, Genus Dissulfobacterium, Genus Dissulfobacter, Genus Dissulfococcus )), Nitrate-reducing bacteria (eg, genus Bacillus, genus Lactobacillus, genus Aeromonas, genus Streptococcus, genus Micrococcus), acid-producing bacteria ( For example, genus Clostridium, genus Acetivibrio, genus Baceroides, genus Ruminococcus, and anaerobic bacteria (eg, genus Bacillus) , Lactoba genus cillus, genus Aeromonas, genus Streptococcus, genus Micrococcus, etc. In particular, genus Bacillus, genus Pseudomonas, genus Aeromonas (Streprococcus genus, Micrococcus genus is preferred because it has an oxidation-type nitrogen-reducing activity)) granules are recovered in the granule recovery tank 1 and returned to the anaerobic tank for the activity in the anaerobic tank-anoxic tank. Nitrifying microorganisms (nitrosomonas, nitrobacter, comamonas, flavoacterium, dysgonomonas nitrosomonas europas, nitrosomonas, Nitrosomonas europaea) The granules of spp., Nitrosospira spp., Nitrobacter spp. genus Nitrospira, etc.) are recovered from the granule recovery tank 2 and returned to the front of the aerobic tank to be activated in the aerobic tank to continuously implement the optimum conditions for each microorganism. In this case, granules composed of heterotrophic microorganisms and granules composed of autotrophic microorganisms may be separately generated and maintained to maintain maximum activity under optimal conditions. As a result, many pollutants can be treated in a short residence time.

Influent wastewater is first treated with phosphorus-removing microorganisms in anaerobic tanks (Phase-removing aerobic microorganisms (PAOs) for aerobacter, Alcaligenes, Bacillus, Brevibacterium, Flavobacterium ( Flavobacterium, Lactobacillus, Micrococcus, etc.) are preferred to have the main functions of elution of organic phosphorus in the wastewater coming in from the outside and intake and storage of organic matter. In this case, phosphorous elution is performed while releasing poly-phosphate accumulated in microbial cells in the mixed solution in the form of ortho-phosphate. In the case of intake and storage of organic matter, the organic matter in the mixed solution is ingested into the cell, and the ingested organic matter is stored in the cell as a poly hydroxy alkanoate (PHA), ie, a secondary metabolite, mainly composed of glycogen and polyhydroxy butyrate (PHB). Phosphorous Removing Bacteria (DPB) microorganisms can be used to remove phosphorus even in low oxygen demand (COD) environments. In the anaerobic tank, a stirrer may be installed to sufficiently mix phosphorus removal microorganisms and waste water.

Thereafter, a denitrification reaction occurs in which the nitrogen is removed from the anaerobic bath. Denitrification by granules of microorganisms occurs by using organic substances present in the introduced wastewater as electron acceptors, and organic substances are simultaneously removed in this process. If denitrification is not sufficiently performed in an oxygen-free tank, the denitrification efficiency may be increased by artificially injecting an external organic carbon source.

In the granule recovery tank 1, the granules of heterotrophic microorganisms are recovered and returned to the front end of the anaerobic tank, and the treated water undergoes an aerobic process for oxidizing ammonia nitrogen. In the aerobic tank, the ammonia nitrogen contained in the treated water is nitrated to nitrate nitrogen, and organic matter not removed in the anoxic tank is oxidized and converted into carbon dioxide.

The decomposed waste water is introduced into the granule recovery tank 2. In granule recovery tank 2, granules and inactive solids of autotrophic microorganisms are separated in a short residence time. The granules of autotrophic microorganisms which settled quickly due to excellent sedimentation are returned to the front end of the aerobic tank using a pump. Inert solids that do not precipitate are introduced into the separation membrane and the treated water and the solids are separated through filtration. The treated water is discharged and the separated inert solids are introduced into the concentrated membrane bath and finally concentrated out of the process. Internal conveyance for conveying the nitrate nitrogen required for denitrification consists of anoxic tank shear.

As described above, according to the present invention, by maintaining the concentration of microorganisms in the bioreactor, anaerobic tank, anaerobic tank and aerobic tank using microbial granules of 20,000mg / L or more, it is possible to stably treat organic matter and nutrients in wastewater in a short time. And the land area for wastewater treatment can be minimized. In addition, by reducing the concentration of activated sludge flowing into the membrane tank, the contamination of the membrane can be minimized. As a result, the energy use of the cleaning process, which is necessary to remove the substances that increase the contamination of the membrane, is reduced, and the process is simplified, and thus the entire treatment process. This has the effect of being simplified.

The present invention has been described above by means of limited embodiments and drawings, but the present invention is not limited thereto and is intended by those skilled in the art to which the present invention pertains. Obviously, various modifications and variations can be made within the equivalent range.

Explanation of Reference Numbers

S _I : Soluble inert COD

S _S : Readily biodegradable COD

SCOD: Soluble chemical oxygen demand, SCOD = S _I + S _S

X _I : Inert suspended organic matter

X _S : Slowly inert COD

XCOD: X _I + X _S

TCOD: XCOD + SCOD

NBDVSS: Biodegradable Organics

BDVSS: Biodegradable Organics

FSS: Fixed Suspended Solids

Claims

Bioreactor in which growth of microbial granules and decomposition of contaminants occur;

A granule recovery tank for separating microbial granules and inert solids, and

Wastewater treatment apparatus comprising a separation membrane tank for separating inert solids and treated water.
The method of claim 1,

Wastewater treatment apparatus further comprises a concentrated separation membrane tank for concentrating the inert solid separated from the separation tank through a separate separation membrane.
The method of claim 1,

The bioreactor is composed of an anaerobic tank, an anaerobic tank, an aerobic tank in order to remove nitrogen and phosphorus wastewater treatment apparatus.
The method of claim 1,

The granule recovery tank is divided into granule recovery tank 1 and granule recovery tank 2, granule recovery of the heterotrophic microorganisms in the granule recovery tank 1 is returned to the front end of the anaerobic tank, granules of independent nutrient microorganisms in the granule recovery tank 2 Waste water treatment apparatus, characterized in that recovered and conveyed to the front end of the aerobic tank.
(a) introducing wastewater into the bioreactor to induce growth of microbial granules and to decompose contaminants;

(b) recovering the microbial granules from inert solids and treated water in a granule recovery tank installed at the rear of the bioreactor and returning them to the front of the bioreactor;

(c) transferring the inert solid and the treated water separated from the microbial granule in the granule recovery tank to the separation membrane tank; And

(d) wastewater treatment method comprising the step of separating the inert solid and the treated water in the separation membrane tank.
The method of claim 5,

The inert solid separated in the separation tank is a wastewater treatment method further comprising the step of concentrating through the separation membrane in a separate separation membrane tank.
(a) introducing wastewater into a bioreactor consisting of anaerobic, anaerobic and aerobic tanks to induce growth of microbial granules and to decompose contaminants;

(b) recovering the microbial granules from the inert solid and the treated water in the granule recovery tank installed at the rear end of the aerobic tank and returning them to the front end of the anaerobic tank;

(c) transferring the inert solid and the treated water separated from the microbial granule in the granule recovery tank to the separation membrane tank; And

(d) wastewater treatment method comprising the step of separating the inert solid and the treated water in the separation membrane tank.
The method of claim 7, wherein

The inert solid separated in the separation tank is a wastewater treatment method further comprising the step of concentrating through the separation membrane in a separate separation membrane tank.
(a) introducing wastewater into a bioreactor consisting of anaerobic tank, anaerobic tank, granule recovery tank 1, aerobic tank and granule recovery tank 2 at the rear end of the aerobic tank to induce growth of microbial granules and decompose contaminants;

(b) recovering the granules of heterotrophic microorganisms from the inert solids and the treated water in the granule recovery tank 1 and returning them to the front end of the anaerobic tank and transferring the inert solids and the treated water separated from the heterotrophic granules to the aerobic tank. step;

(c) recovering granules of autotrophic microorganisms from the granule recovery tank 2 at the rear end of the aerobic tank and returning them to the front end of the aerobic tank;

(d) transferring the inert solid and the treated water separated from the granules of the autotrophic microorganism in the granule recovery tank 2 to the separation membrane tank; And

(e) the wastewater treatment method comprising the step of separating the inert solid and the treated water in the separation membrane tank.
The method of claim 9,

The inert solid separated in the separation tank is a wastewater treatment method further comprising the step of concentrating through the separation membrane in a separate separation membrane tank.