KR101336988B1 - Wastewater Treatment Apparatus Using Granule Sludge and Method for Treating Wastewater Using the Same - Google Patents

Abstract

The present invention relates to a sewage and wastewater treatment apparatus and method using granular sludge, and more particularly, anaerobic granular sludge, first aerobic granular sludge, and first anaerobic tank, anoxic tank, first aeration tank and a second aeration tank each equipped with a separator plate. The present invention relates to an apparatus and method for treating sewage and wastewater using granular sludge which greatly improves the treatment efficiency of pollutants such as organic matter, nitrogen and phosphorus in sewage and wastewater by injecting aerobic granular sludge and nitrified granular sludge, respectively.
The sewage and wastewater treatment apparatus using granular sludge according to the present invention is a conventional biological water treatment apparatus and method based on suspended microorganisms while treating sewage and wastewater stably from the beginning of operation by filling high-quality granular sludge into each reactor. Smooth aftertreatment process is possible by solving the problem of bulking and foaming, and suspended microorganisms are separated and discharged from granular sludge to maintain high concentration of granular sludge in the device, so it is resistant to impact load and short hydraulic residence time. By minimizing the volume of the device according to the above, it is possible not only to reduce equipment and maintenance costs, but also to use it as a retrofitting technology of the conventional sewage and wastewater treatment facilities to maximize the treatment efficiency of organic matter, nitrogen and phosphorus contained in the sewage and wastewater. have.

Description

Wastewater Treatment Apparatus Using Granule Sludge and Method for Treating Wastewater Using the Same}

The present invention relates to a sewage and wastewater treatment apparatus and method using granular sludge, and more particularly, anaerobic granular sludge, first aerobic granular sludge, and first anaerobic tank, anoxic tank, first aeration tank and a second aeration tank each equipped with a separator plate. The present invention relates to a sewage and wastewater treatment apparatus and method using granular sludge, which significantly improves the treatment efficiency of pollutants such as organic matter, nitrogen and phosphorus in sewage and wastewater by filling aerobic granular sludge and nitrified granular sludge, respectively.

Conventional activated sludge is the most widely used and long-established biological treatment method in most countries as well as in Korea.

However, the strengthened legislation for the improvement of water quality of rivers and lakes is focused on the high-treatment process in addition to organic matters, and the current domestic situation is still inadequate for the installation of the high-treatment process, and retrofitting technology to compensate for this. There is no commercialization.

In Korea, a large-scale sewage treatment plant is mainly applied with a continuous flow advanced treatment method, and in the case of small and medium-sized plants, a sequencing batch reactor (SBR) method is frequently applied for the purpose of elastic response of inflow flow rate. have. The continuous flow sewage treatment methods such as A / O or A ² / O are differentiated according to the target materials to be treated. In Korea, many methods for simultaneously removing nitrogen and phosphorus are being developed and applied.

However, unlike in other countries, the distribution rate of sewage pipes in Korea is low, and the sewage drainage system is a conduit-type conduit, so the C / N ratio, which is a ratio of organic matter required for nitrogen and phosphorus removal, is low, making it difficult to efficiently operate the development method. In particular, when technology developed in foreign countries is introduced and applied in Korea, it is impossible to obtain the desired effect because technical review such as design factor change is not sufficient in advance.

In the advanced biological treatment method using suspended microorganisms, since the floating microorganisms continue to move to each tank by continuous flow or sludge return, it is difficult to dominate each tank condition, and the efficiency of removing pollutants is inferior. In addition, there are various problems in solid-liquid separation and treatment efficiency, such as frequent occurrence of bulking and foaming depending on the characteristics of the influent and the operation method.

Accordingly, in order to solve such disadvantages of suspended microorganisms in Korea, an immersion type membrane separation process (MBR) has been applied to replace solid-liquid separation by gravity precipitation with membrane separation and increase the concentration of microorganisms in the reactor to improve treatment efficiency. However, like the conventional membrane separation process, the immersion type membrane separation process needs to replace the membrane periodically due to the membrane fouling phenomenon according to the membrane permeation time, and the excessive DO concentration in the aeration tank is supplied by supplying excessive air in the aeration tank for cleaning the membrane. It is pointed out that it is maintained, and thus high energy consumption is consumed.

 Efforts have been made to improve the problems of the conventional biological water treatment apparatus and method as mentioned above, and as part of such efforts, Korean Patent No. 0357042 and Korean Patent No. 0345451 have been used to granulate floating microorganisms instead of floating microorganisms. Disclosed is a water treatment apparatus and method for treating sewage by ignition.

Specifically, the Korean Patent No. 0357042 has become rich in dissolved oxygen in the water treatment apparatus and indirect aeration tank, the core configuration of the indirect aeration tank for supplying air, the granulation bioreactor with a stirrer for granulating suspended microorganisms A method of treating sewage is disclosed by supplying an aeration mixture liquid to a biological reaction tank in an upflow manner, maximizing contact between floating microorganisms by the hydraulic power of the aeration mixture liquid, and allowing granulation to occur. In Korean Patent No. 0345451, an anaerobic granulation tank is added in addition to the indirect aeration tank and the biological reaction tank, which are essential components of the Korean Patent No. 0357042, to dominate the organic matter, nitrogen, and A water treatment apparatus and method for removing contaminants such as phosphorus are disclosed.

Common to these patents is a method of generating granular sludge from suspended microorganisms by controlling operating conditions and the like in a water treatment apparatus, and the production of granular sludge through granulation of suspended microorganisms is not only time-consuming but also uniform in size. Because it is difficult to produce granular sludge of sewage, there is a disadvantage that it is difficult to treat sewage water stably. In addition, the water treatment device disclosed in the patent is not only because the suspended sludge and suspended microorganisms resident because it is impossible to separate the granular sludge and suspended microorganisms, but also due to the floating microorganisms in the settling tank installed at the rear end because it is difficult to control the concentration of the suspended microorganisms. It is difficult to solve the fundamental problem of the advanced biological treatment method using suspended microorganisms such as the sedimentation tank sludge bulking problem.

Finally, the water treatment apparatus and method disclosed in the patent has the disadvantage of adding an indirect aeration tank and a granulation bioreactor, the retrofitting technology of the A / O or A ² / O process that occupies most of the existing wastewater treatment facilities It has a structure that is difficult to use.

Accordingly, the present inventors have made efforts to solve the problems of the prior art, the anaerobic granular sludge, the first aerobic granular sludge, the second aerobic granular sludge and the anaerobic tank, the anaerobic tank, the first aeration tank and the second aeration tank, respectively provided with a separator plate When injecting nitrified granular sludge respectively, the removal efficiency of organic matter, nitrogen, and phosphorus contained in sewage and wastewater is not only improved, and the solid-liquid separation is possible to confirm that the post-treatment process is easy to operate and to complete the present invention. It became.

The main object of the present invention is the sewage and wastewater treatment apparatus capable of smooth solid-liquid separation, which facilitates the post-treatment process operation, minimizes the volume of the apparatus, and improves the treatment efficiency of pollutants such as organic matter, nitrogen, and phosphorus. And providing a method.

In order to achieve the above object, the present invention is filled with anaerobic granular sludge, equipped with a stirrer to agitate the anaerobic granular sludge, the anaerobic tank for performing phosphorus release and organic matter removal of the sewage and wastewater introduced from the outside ; An anoxic tank filled with a first aerobic granular sludge and equipped with a stirrer to stir the aerobic granular sludge to perform denitrification and organic matter removal of the treated water in the anaerobic tank; A first aeration tank filled with a second aerobic granular sludge and equipped with an air supply unit for supplying air, and performing nitrification, organic matter oxidation and phosphorus excess intake of the treated water treated in the anoxic tank; A second aeration tank filled with nitrified granular sludge and equipped with an air supply unit for supplying air, and performing nitrification, organic matter oxidation and phosphorus excess intake of the treated water treated in the first aeration tank; A settling tank for separating and discharging the floating microorganisms contained in the treated water treated in the second aeration tank; And an internal circulation unit having an internal circulation pump for circulating the treated water treated in the second aeration tank to the anoxic tank.

The present invention also comprises the steps of (a) flowing wastewater into an anaerobic tank filled with anaerobic granular sludge to perform dephosphorization and organic matter removal; (b) introducing the treated water from which dephosphorization and organics have been removed into an anaerobic tank filled with first aerobic particulate sludge to perform denitrification and organics removal; (c) introducing the treated water from which denitrification and organic matter is removed into a first aeration tank filled with a second aerobic particulate sludge to perform nitrification, organic matter oxidation and phosphorus excess ingestion; (d) introducing the treated water removed from the first aeration tank into a second aeration tank filled with nitrifying granular sludge to redo nitrification, organic matter oxidation and phosphorus excess intake; (e) separating and discharging the floating microorganisms by introducing the treated water treated in the second aeration tank into the settling tank; And (f) transferring the treated water treated in the second aeration tank to an anaerobic tank using an internal circulation pump, and then repeatedly performing steps (b), (c), (d) and (e). It provides a sewage and wastewater treatment method using the sewage and wastewater treatment apparatus, including removing organic matter, nitrogen, and phosphorus from wastewater.

The sewage and wastewater treatment apparatus using granular sludge according to the present invention is a conventional biological water treatment apparatus and method based on suspended microorganisms while treating sewage and wastewater stably from the beginning of operation by filling high-quality granular sludge into each reactor. Smooth aftertreatment process is possible by solving the problem of bulking and foaming, and suspended microorganisms are separated and discharged from granular sludge to maintain high concentration of granular sludge in the device, so it is resistant to impact load and short hydraulic residence time. By minimizing the volume of the device, it is possible to reduce the installation and maintenance costs, and can be utilized as a retrofitting technology of the conventional sewage and wastewater treatment facilities. In addition, by preventing the movement of granular sludge in each reaction tank, it is possible to obtain granular sludge in which the microorganisms in each reactor are dominated, thereby maximizing the treatment efficiency of organic matter, nitrogen and phosphorus contained in sewage and wastewater.

1 is a schematic diagram of a sewage and wastewater treatment apparatus using granular sludge according to the present invention.

According to an aspect of the present invention, an anaerobic granular sludge is filled, an agitator for stirring the anaerobic granular sludge is mounted at a lower portion thereof, and an anaerobic tank for performing phosphorus discharge and organic matter removal from sewage and wastewater introduced from the outside; An anoxic tank filled with a first aerobic granular sludge and equipped with a stirrer to stir the aerobic granular sludge to perform denitrification and organic matter removal of the treated water in the anaerobic tank; A first aeration tank filled with a second aerobic granular sludge and equipped with an air supply unit for supplying air, and performing nitrification, organic matter oxidation and phosphorus excess intake of the treated water treated in the anoxic tank; A second aeration tank filled with nitrified granular sludge and equipped with an air supply unit for supplying air, and performing nitrification, organic matter oxidation and phosphorus excess intake of the treated water treated in the first aeration tank; A settling tank for separating and discharging the floating microorganisms contained in the treated water treated in the second aeration tank; And an internal circulation unit having an internal circulation pump for circulating the treated water treated in the second aeration tank to the anoxic tank.

More specifically, the sewage and wastewater treatment apparatus using the granular sludge according to the present invention relates to a continuous flow advanced treatment apparatus in which an anaerobic tank, an anaerobic tank, a first aeration tank, and a second aeration tank are sequentially arranged. In order to maximize the treatment efficiency of pollutants such as organic matter, nitrogen and phosphorus, and to minimize the volume of the device according to the short hydraulic residence time, and to facilitate smooth solid-liquid separation in the post-treatment process, anaerobic tank, anoxic tank, and first A device for treating sewage and wastewater by sequentially arranging the aeration tank and the second aeration tank, and then injecting high-quality anaerobic granular sludge, first aerobic granular sludge, and second aerobic granular sludge and nitrified granular sludge, respectively, prepared in the reactor. will be.

Here, the 'reaction tank' refers to each anaerobic tank, anoxic tank, the first aeration tank and the second aeration tank. In addition, 'granular sludge' refers to the self-immobilization of microorganisms contained in activated sludge by biological, physical, and chemical factors without expensive carriers, biofilms such as rotating bodies, etc. It is called.

Hereinafter, the present invention will be described in detail with reference to the drawings.

As shown in Figure 1, the sewage and wastewater treatment apparatus using the granular sludge according to the present invention is anaerobic tank (5), anoxic tank (10), the first aeration tank (15), the second aeration tank (20), sedimentation tank (25) and It includes an inner circulation (30).

In the present invention, the anaerobic tank (5) is maintained in the anaerobic state to perform phosphorus release and organic matter decomposition of the sewage, wastewater introduced from the outside, the anaerobic granular sludge (6) is filled, and stirred the anaerobic granular sludge The stirrer t is mounted at the bottom.

The anaerobic granular sludge (6) is manufactured externally and injected into the anaerobic tank (5), and is prepared using phosphorus-releasing and hardly degradable organic matter removing microorganisms, preferably Micrococcus and Pseudomonas . ah is manufactured using a high concentration of anaerobic microorganisms such as Como bakteo (Archomobacter), Bacillus (Bacillus), para cock kusu (Paracoccus), acetonitrile tumefaciens (Acetobacterium).

In addition, the anaerobic granular sludge may be inoculated into the reactor to release the phosphorus release and hardly decomposable organic matter microorganisms, and nitrogen gas is injected into the reactor to form an upflow, and at the same time, anaerobic granular sludge may be manufactured through a continuous batch operation.

The average diameter of the prepared anaerobic granular sludge (6) is preferably 0.5 to 2 mm, if the average diameter of the anaerobic granular sludge is less than 0.5 mm, there is a problem that the sedimentation is lowered and it is difficult to maintain a high concentration of microorganisms, the average diameter If the thickness exceeds 2 mm, the structure of the anaerobic granular sludge may be weakened due to the organic matter restriction inside the anaerobic granular sludge.

In addition, the amount of the anaerobic granular sludge 6 filled in the anaerobic tank 5 is injected by adjusting the mixed liquid suspended solids (MLSS) of the anaerobic tank according to the hardly decomposable organic matter and phosphorus concentration of the waste water. Preferably it is injected at 2,000 ~ 30,000 mg / L to fill the anaerobic tank (5). When the concentration of mixed liquid suspended solids (MLSS) in the anaerobic tank (5) filled with anaerobic granular sludge (6) is less than 2,000 mg / L, it is difficult to remove hardly decomposable organic substances and release phosphorus. If the concentration exceeds 30,000 mg / L there is a problem that the anaerobic granular sludge structure is weakened due to the lack of organic matter.

The high concentration of anaerobic granular sludge can be concentrated in the long-term contact with the hardly decomposable substance, thereby enhancing the degradability of the anaerobic microorganisms against the hardly decomposable substance, and as a result, the hardly decomposable substance is quickly decomposed and removed. In particular, since anaerobic microorganisms have better adhesion than suspended solids, anaerobic microorganisms can be maintained at a high concentration more efficiently than using a carrier.

In addition, anaerobic granular sludge injection can induce denitrification due to the growth of anaerobic microorganisms and can remove nitrate nitrogen, and organic acids can be generated and used as organic sources during the digestion of hardly decomposable organic matter. There is an advantage to reduce the input.

In general, organic matter is formed not only when nitrate nitrogen (NO _x - N) is released (denitrified) with nitrogen (N ₂ ) gas, but also when phosphorus accumulating microorganisms convert organic substances into poly (β- It is also important to remove the nitrogen and phosphorus contained in the wastewater, and it is important that organics are important factors and that the limited organic matter is appropriately distributed to the denitrifying microorganisms and the direct microorganisms.

In particular, when the phosphorus accumulating microorganisms and the denitrifying microorganisms are in competition, the denitrifying microorganisms become dominant because they take up organic matter relatively first than the phosphorus accumulating microorganisms. Therefore, it is necessary to reduce the disturbance of toxic substances of nitrate nitrogen by allowing limited organic matter to be supplied to phosphorus accumulating microorganisms as soon as possible, thereby activating the activity of relatively weaker microorganisms as compared with denitrifying microorganisms, so that simultaneous treatment of nitrogen and phosphorus do.

 Therefore, the sewage and wastewater treatment apparatus using the granular sludge according to the present invention is injected into the anaerobic tank anaerobic granular sludge into the anaerobic tank, so as to supply the limited organic matter to the accumulating microorganism as early as possible, causing toxicity of nitrate nitrogen By reducing the interference of substances, it activates the activity of weaker microorganisms, which are relatively weaker than denitrifying microorganisms, and maintains the high mixed liquid suspended solids (MLSS) concentration by anaerobic granular sludge to combine with the role of aerobic granular sludge described below. It is configured so that simultaneous processing of phosphorus can occur easily.

 The sewage / wastewater treatment apparatus using the granular sludge of the present invention first receives the wastewater into the anaerobic tank, and receives organic matters by supplying the organic matters of the introduced wastewater and wastewater smoothly, thereby activating the activity of phosphorus-scale microorganisms to increase dephosphorization efficiency. The growth conditions of anaerobic granular sludge are maintained.

In other words, phosphorus compounds (in the state of acetic acid ions) in the influent sewage and wastewater are produced from anaerobic granular sludge (PAOs, phosphate accumulating organisms, PAOs) that have sufficient carbon sources (nutrients) in the anaerobic state. The main dominant species spreads and moves into the cells of acinetobacters, using acetyl coenzymes (AcCoA, Acetyl-CoA) using energy generated by the breakdown of intracellular phosphate polymers (poly-P, poly-phosphate) in the anaerobic state (ATP). ) is changed to, as AcCoA is through the TCA (tricarboxylic acid) Cycle stored as PHB (poly-β-hydroxybutyrate) state actively phosphate ions (P ^- emits).

On the other hand, the anaerobic tank is equipped with a stirrer (t) in the lower portion of the anaerobic tank to agitate the anaerobic granular sludge (6), is provided with at least one separation plate (s) spaced apart at a predetermined interval from the bottom of the anaerobic tank. The stirrer t can be used without limitation as long as it is a stirrer used for sewage and wastewater treatment. In addition, the separation plate (s) is mounted at one side of the anaerobic tank spaced apart from the bottom of the anaerobic tank at a predetermined interval in order to prevent the anaerobic granular sludge filled in the anaerobic tank is moved to the anoxic tank 10 to be described later.

The plurality of separation plates (s) may be installed without limitation as long as it can prevent anaerobic granular sludge from flowing into the anaerobic tank, but preferably two so as not to interfere with the movement of the anaerobic granular sludge. It is mounted parallel to the plurality of separation plates spaced apart from each other. The first one of the plurality of separators (s) thus provided (the first one in the direction in which the treated water is introduced) prevents anaerobic granular sludge from passing to the next reactor, and the second separator is the first one. Anaerobic granular sludge that has exceeded is prevented from bumping into the next reactor. On the other hand, in the case of floating microorganisms in the inflow and wastewater, the sedimentation properties are low, so that the floating microorganisms can be introduced into the next reaction tank by passing under the second separation plate and treated.

In the present invention, the anoxic tank 10 is maintained in an oxygen-free state so that denitrification and organic matter removal of the treated water treated in the anaerobic tank 5 is carried out, the first aerobic granular sludge 11 is filled, the first A stirrer t for stirring the aerobic granular sludge 11 is mounted at the bottom.

The first aerobic granular sludge 11 microcode kusu (Micrococcus), ahsine Sat bakteo (Acinetobacter), Bacillus (Bacillus), bakteo (Arthrobacter), arc bakteo (Achrobacter), Agrobacterium (Agrobacterium) into Ars, Pseudomonas (Pseudomonas), O Como bakteo (Archomobacter), chromotherapy tumefaciens (Chromobacterium), Flavobacterium (Flavobacterium), and in a jugeul is made of aerobic and facultative anaerobic microorganisms such as Ah (Zoogloea), preferably denitrification microorganisms Can be used.

In the method of preparing the first aerobic granular sludge, the aerobic and breathable anaerobic microorganisms are inoculated into the reactor, the air is injected to form an upflow, and the first aerobic granular sludge can be produced through a continuous batch operation.

In addition, the average diameter of the first aerobic granular sludge 11 is 0.5 to 2 mm, if the average diameter of the first aerobic granular sludge is less than 0.5 mm It is difficult to maintain high settled suspended solids (MLSS) and sedimentation properties, and if the average diameter exceeds 2mm, the structure of the first aerobic granular sludge may be weakened due to the organic matter restriction inside the first aerobic granular sludge. have.

In addition, in the present invention, the amount of the first aerobic particulate sludge 11 to be filled in the oxygen-free tank 10 is filled by adjusting the mixed liquid suspended solids (MLSS) of the oxygen-free tank according to the organic matter and nitrogen concentration contained in the waste water. Preferably it is filled to 2,000 to 30,000 mg / L. When the concentration of mixed liquid suspended solids (MLSS) in the reactor filled with the first aerobic granular sludge is less than 2,000 mg / L, denitrification and organic matter removal are not performed smoothly, and the concentration of the mixed liquid suspended solids (MLSS) is 30,000 mg / L. If exceeded, there is a problem of weakening the first aerobic particulate sludge structure due to the lack of organic matter.

In the oxygen-free tank 10, harmless nitrogen by the first aerobic granular sludge predominantly NO ₃ ^-- N produced by nitrification in the first aeration tank 15 and the second aeration tank 20 which will be described later. It is reduced to gas (N ² ) and released into the atmosphere. The denitrifying microorganisms contained in the aerobic granular sludge 11 are facultative heterotrophic bacteria unlike the nitrification reaction. In order to activate the denitrification of the first aerobic granular sludge dominated by denitrified microorganisms, an oxygen free environment and a sufficient supply of organic matter are absolutely necessary. Representative denitrifying microorganisms may include microcode kusu (Micrococcus), Pseudomonas (Pseudomonas), O Como bakteo (Archomobacter), Bacillus (Bacillus). The denitrification scheme is as follows.

^{_{NO 3 - + 1.08CH 3 OH +}} H → 0.065C 5 H 7 O 2 N + 0.47N 2 + 0.76C0 2 + 2.44H 2 O

On the other hand, the oxygen-free tank 10 is equipped with a stirrer (t) in the lower portion of the oxygen-free tank to agitate the first aerobic granular sludge 11, at least one separation plate (s) mounted spaced apart from the oxygen-free tank bottom at a predetermined interval. It is provided. The stirrer t can be used as long as it is a stirrer used for sewage and wastewater treatment. In addition, the separating plate (s), such as the above-described anaerobic separation plate (s) of the first anaerobic granular sludge filled in the anaerobic tank to prevent the transfer to the first aeration tank 15 to be described later at a predetermined interval from the bottom of the anaerobic tank. It is spaced apart and mounted in a large number inside one side of the anaerobic tank. The plurality of separators s may be mounted without limitation as long as the structure can prevent the first aerobic granular sludge from flowing into the first aeration tank. Preferably, the plurality of separators s may be spaced apart from each other and parallel to the anoxic tank inner wall or the plurality of separators. Is mounted.

In the present invention, the first aeration tank 15 is maintained in an aerobic state so that nitrification, organic matter oxidation and excess phosphorus intake of the treated water treated in the anoxic tank 10 are performed, and the second aerobic granular sludge 16 is Filled, the air supply (a) for supplying air is mounted at the bottom.

The second aerobic granular sludge 16 is nitro consumption eggplant (Nitrosomonas), nitroso Rhodococcus (Nitrosococcus), nitro source pyrazole (Nitrosospira), nitro bakteo (Nitrobacter), nitro Rhodococcus (Nitrococcus), coma Pseudomonas (Comamonas), ahsine Sat bakteo (Acinetobacter), difficulties bakteo (Aerobacter), Proteus vulgaris (Proteus vulgaris), Flavobacterium (Flavobacterium), discharge Kono Pseudomonas (Dysgonomonas), arc bakteo (Achrobacter), bakteo (Arthrobacter) in Ars, Pseudomonas (Pseudomonas ), and the aerobic and facultative anaerobic microorganisms such as Bacillus (Bacillus) and O (Zoogloea) in a jugeul, can be preferably used an organic substance oxidation, the scale and nitrification microorganisms.

As a method for producing the second aerobic granular sludge 16, the aerobic and breathable anaerobic microorganisms may be inoculated into a reactor, air is injected to form an upflow, and the second aerobic granular sludge may be manufactured through a continuous batch operation.

The average diameter of the second aerobic granular sludge is 0.5 to 2 mm. If the average diameter of the second aerobic granular sludge is less than 0.5 mm, the sedimentability is poor and it is difficult to maintain a high mixed liquid suspended solids (MLSS), and the average diameter is 2 mm. If exceeded, the structure of the aerobic granular sludge may be weakened due to the organic matter and nitrogen limitation inside the second aerobic granular sludge.

In addition, in the present invention, the amount of filling the second aerobic particulate sludge in the first aeration tank 15 is filled by adjusting the mixed liquid suspended solids (MLSS) of the first aeration tank in accordance with the organic matter and nitrogen concentration contained in the waste water. . Preferably it can be filled to 2,000 to 30,000 mg / L. This is because when the concentration of mixed liquid suspended solids (MLSS) in the reactor filled with the second aerobic granular sludge is less than 2,000 mg / L, nitrification and organic matter oxidation are not performed smoothly, and the concentration of the mixed liquid suspended solids (MLSS) is 30,000 mg / L. In the case of more than 2, there is a problem that the second aerobic particulate sludge structure is weakened due to the lack of organic matter and nitrogen .

In the first aeration tank 15, the second aerobic granular sludge 16 undergoes the above-described process, thereby overingestion of phosphorus, nitrification and organic oxidation. The organic matter oxidation is obtained by actively decomposing organic matter by aerobic suspended microorganisms contained in the second aerobic granular sludge and sewage and wastewater in the first aeration tank 15 to obtain energy, and by synthesizing cells, Cell (C ₅ H ₇ O ₂ N), CO ₂ And then removed. At this time, 0.12 kg of nitrogen and 0.025 kg of phosphorus are consumed to synthesize 1 kg of C ₅ H ₇ O ₂ N. This is expressed as follows.

CHON + O ₂ + Nutrients → C ₅ H ₇ O ₂ N + CO ₂ + NH ₃ + Other products

In addition, the nitrification reaction in the first aeration tank 15 is performed by aerobic microorganisms [organic nitrogen] and ammonia nitrogen (NH ₃ -N) contained in the sewage and wastewater contained in the second aerobic granular sludge [nitroso consumption It is converted into NH ₃ -N by the degradation of Aerobic Autotrophic Bacteria] such as Natros ( Nitrosomonas ) and Nitrobacter . NH ₃ -N is converted to nitrate nitrogen (NO ₃ ^-- N) via nitrite nitrogen (NO ₂ ^-- N) by the microorganism oxidizing it. These microorganisms grow by oxidizing ammonia with oxygen. The nitrification of ammonia in water in the form of ammonia ions (NH ₄ ⁺ ) is as follows.

^{_{22NH 4 + + 37O 2 + 4CO}} 2 + HCO 3 - → C 5 H 7 O 2 N + 21NO 3 - + 20H 2 O + 42H +

Phosphate accumulating organisms (PAOs) contained in the second aerobic granular sludge in the first aeration tank 15 ingest the phosphate ions (orthophosphate) from the outside while decomposing PHB stored in the cell into oxygen in an aerobic state. It is stored intracellularly in the form of -phosphate. In order to continue supplying the energy source (ATP) necessary for the synthesis process, the phosphorus intake by PAOs (the main predominant species of PAOs is Acinetobacter) increases from the outside, and these high phosphorus intake microorganisms are suspended in the second aerobic granular sludge. It is separated into microbial forms and discharged together with aerobic suspended microorganisms contained in sewage and wastewater. The discharged suspended microorganisms are removed by a settling tank (with or without a separator) to finally remove phosphorus.

On the other hand, in the first aeration tank 15, the second aerobic granular sludge 16 is floated upward, and an air supply part a for supplying air to maintain an aerobic state is mounted at the bottom. Accordingly, the air supply unit (a) can be used as long as it is a conventional member for supplying air used for water treatment, and supplies air from the lower part of the first aeration tank to the upper part. In addition, the separating plate (s) is spaced at a predetermined interval from the bottom of the first aeration tank in order to prevent the second aerobic granular sludge filled in the first aeration tank to move to the second aeration tank 20 which will be described later, one side of the first aeration tank It is equipped with a large number.

The plurality of separation plates (s) can be installed without limitation as long as the configuration can prevent the second aerobic granular sludge from flowing into the second aeration tank, preferably four are on the inner wall of the first aeration tank or a plurality of separation plates. Spaced apart and mounted in parallel. Air is injected between the first separator (the first separator in the direction in which the treated water flows from the anoxic tank flows) and the second separator so that the granular sludge floats, and the second aerobic granular sludge is separated between the second separator. Is circulated in the reactor as it descends. The third and fourth separators prevent the second aerobic particulate sludge from entering the second aeration tank, such as the anaerobic and anoxic separators described above.

In the present invention, the second aeration tank 20 is maintained in an aerobic state so that nitrification, organic matter oxidation and excess phosphorus intake of untreated treated water in the first aeration tank 15 are performed, and nitrified granular sludge 21 is formed. Filled, the air supply (a) for supplying air is mounted at the bottom.

The nitride granular sludge 21 can be made by using the nitrifying microorganism is preferably a nitro consumption eggplant (Nitrosomonas), nitroso Rhodococcus (Nitrosococcus), nitro source pyrazole (Nitrosospira), nitro Thoreau bus (Nitrosolobus), a nitro cattle can be used for the aerobic and facultative anaerobic microorganisms such as brioche (Nitrosorobrio), nitro bakteo (Nitrobacter), nitro Rhodococcus (Nitrococcus), nitro Spira (Nitrospira), knitted Los Pina (Nitrospina), O (Zoogloea) in a jugeul.

As a method for preparing nitrified granular sludge, nitrified microorganisms may be inoculated into a reactor, injected with air to form upflow, and nitrified granular sludge may be produced through a continuous batch operation.

The average diameter of the nitrified granular sludge 21 is 0.5 to 1 mm. If the average diameter of the nitrified granular sludge is less than 0.5 mm, the sedimentation properties are poor and it is difficult to maintain a high mixed liquid suspended solids (MLSS), and the average diameter is 1 mm. If exceeded, the structure of nitrified granular sludge may be weakened due to nitrogen limitation in the granular sludge.

The amount to fill the nitrified granular sludge in the second aeration tank is filled by adjusting the mixed liquid suspended solids (MLSS) of the reactor according to the nitrogen concentration of the waste water. Preferably it can be filled to 2,000 to 7,000 mg / L. This is because when the concentration of the mixed liquid suspended solids (MLSS) in the reactor filled with nitrified granular sludge is less than 2,000 mg / L, the nitrification does not occur smoothly. When the concentration of the mixed liquid suspended solids (MLSS) exceeds 7,000 mg / L, There is a problem that the nitrification granular sludge structure is weakened due to the lack of nitrogen.

Aerobic autotrophic microorganisms and aerobic heterotrophic microorganisms (organic oxidizing microorganisms, etc.) compete with each other because they obtain energy from electrons as electron acceptors. In general, activated sludge is composed of about 90% or more of aerobic heterotrophic microorganisms and about 10% or less of aerobic autotrophic microorganisms. The nitrified granular sludge is composed of aerobic autotrophic microorganisms such as nitrosomonas ( Nitrosomonas ) and nitrobacter (nitrogen microorganisms, nitrite microorganisms, etc.), which are 30 to 70%, and the treated water flowing in the first aeration tank is Since it has a low organic matter concentration, it shows about 5 ~ 10 times higher nitrification rate than general activated sludge.

On the other hand, the second aeration tank 20 is floated to the upper nitrified granular sludge 21, the air supply unit (a) for supplying air to maintain the exhalation state is mounted at the bottom. Accordingly, the air supply unit (a) can be used as long as it is a conventional member for supplying air used for water treatment, and supplies air from the bottom of the second aeration tank to the top. In addition, the separation plate (s), like the separation plate of the first aeration tank described above, at a predetermined interval from the bottom of the second aeration tank to prevent the nitrified granular sludge filled in the second aeration tank from being moved to the settling tank 25 which will be described later. Spaced apart is mounted a plurality of inside the second aeration tank. The plurality of separators s may be mounted without limitation as long as the nitrate granular sludge is configured to prevent inflow into the sedimentation tank, and is preferably spaced apart from and parallel to the inner wall of the second aeration tank or a plurality of separation plates. do.

In the present invention, the settling tank 25 separates and discharges the suspended microorganisms contained in the treated water treated in the second aeration tank 20. Separation and discharge of the suspended microorganism may be performed by the separator 26 immersed in the settling tank. The separation membrane may be used in the form of hollow fiber membrane, tubular, hollow fiber, spiral, plate, rotary plate, and the like.

In the present invention, since the movement of granular sludge is suppressed in each reactor, suspended sludge existing in the influent and the surface of the granular sludge are introduced into the sedimentation tank. Therefore, the concentration of mixed liquid suspended solids (MLSS) in the settling tank is lower than that of activated sludge, and the suspended sludge separated from the granular sludge also has a higher SVI (Sludge Volume Index) than the general activated sludge, so that a small settling tank can be installed and operated. In addition, even when the membrane is immersed in the settling tank, the backwash cycle of the immersed membrane is maintained for a long time.

In the present invention, the internal circulation part 30 is provided with an internal circulation pump 31 to circulate the treated water treated in the second aeration tank 20 to the anoxic tank 10. The treated water subjected to nitrification, organic matter oxidation and phosphorus excess intake in the second aeration tank 20 is transferred to the anaerobic tank 10 again through an internal circulation pump 31 provided in the internal circulation unit 30 to denitrify and organic matter. Removal is performed.

The sewage and wastewater treatment apparatus according to the present invention is provided with a separation plate (s) in each reaction tank to separate and discharge suspended microorganisms from each granular sludge to maintain high concentrations of anaerobic, aerobic and nitrified granular sludge in the apparatus, and short hydraulic power. By minimizing the volume of the device according to the chemical residence time, not only can the equipment and maintenance cost be reduced, but also the composition of the reactor and A / O or A ² / O process that takes up most of the conventional sewage and wastewater treatment facilities is similar. It can be used as a retrofitting technology for sewage and wastewater because it can be used without major structural changes in sewage and wastewater treatment facilities.

In addition, the sewage and wastewater treatment apparatus according to the present invention uses anaerobic granular sludge in which dephosphorization and hardly decomposable organic matter-decomposing microorganisms are predominantly used in an anaerobic tank, and aerobic granular sludge in which denitrifying microorganisms are predominantly seeded is used in an anaerobic tank, and phosphorus excess intake Treatment of organic matter, nitrogen and phosphorus contained in sewage and wastewater by using aerobic granular sludge dominated by nitrification and organic matter oxidizing microorganisms in the first aeration tank, and nitrifying granulated sludge dominated by nitrifying microorganisms in the second aeration tank The efficiency can be maximized.

According to another aspect of the present invention, there is provided a method for removing demineralization and organic matter by (a) introducing sewage and wastewater into an anaerobic tank filled with anaerobic granular sludge; (b) introducing the treated water from which dephosphorization and organics have been removed into an anaerobic tank filled with first aerobic particulate sludge to perform denitrification and organics removal; (c) introducing the treated water from which denitrification and organic matter is removed into a first aeration tank filled with a second aerobic particulate sludge to perform nitrification, organic matter oxidation and phosphorus excess ingestion; (d) introducing the treated water removed from the first aeration tank into a second aeration tank filled with nitrifying granular sludge to redo nitrification, organic matter oxidation and phosphorus excess intake; (e) separating and discharging the floating microorganisms of the treated water treated in the second aeration tank; And (f) transferring the treated water treated in the second aeration tank to an anaerobic tank using an internal circulation pump, and then repeatedly performing steps (b), (c), (d) and (e). It relates to a sewage and wastewater treatment method using the sewage and wastewater treatment apparatus, including removing organic matter, nitrogen, and phosphorus from wastewater.

The sewage and wastewater treatment method according to the present invention relates to a sewage and wastewater treatment method using the above-described wastewater and wastewater treatment apparatus. First, the wastewater and wastewater are introduced into an anaerobic tank 5 filled with anaerobic granular sludge 6. The dephosphorization and organic matter decomposition and removal are performed, and the treated water from which the dephosphorization and organic matter is decomposed and removed is introduced into the anoxic tank 10 filled with the first aerobic granular sludge 11 to perform denitrification and organic matter decomposition. The treated water subjected to denitrification and decomposition of organic matter is introduced into the first aeration tank 15 filled with the second aerobic granular sludge 16 to perform nitrification, organic matter oxidation and phosphorus excess intake, and then nitrification granular sludge (21). ) Is introduced into the second aeration tank 20 filled. The second aeration tank 20 re-executes untreated nitrification, organic matter oxidation and phosphorus excess ingestion in the first aeration tank 15, and flows the treated water treated in the second aeration tank 20 into the settling tank 25 to float the microorganisms. Is separated by a separator 26, and the final treated water is discharged. In addition, the treated water in which nitrification, phosphorus excess, and organic matter are oxidized in the second aeration tank 20 is transferred to the oxygen-free tank 10 using the internal circulation pump 31, and then the above-described steps are repeated.

The sewage and wastewater treatment method of the present invention does not produce anaerobic, aerobic and nitrified granular sludge in the apparatus, and then treats the sewage and wastewater using the granular sludge produced above, but with high quality anaerobic, aerobic and nitrified granular sludge. By injecting the granulated sludge into each reactor, it is possible to stably process wastewater and wastewater from the beginning of operation, and to solve bulking and foaming, which is a problem of the conventional biological water treatment apparatus and method based on suspended microorganisms. .

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are only for illustrating the present invention, it will be apparent to those skilled in the art that the scope of the present invention is not to be construed as being limited by these examples.

Example  1: Treatment efficiency and separation membrane of sewage and wastewater treatment apparatus according to the present invention Backwash  Periodic measurement

As shown in FIG. 1, a sewage and wastewater treatment apparatus using granular sludge according to the present invention was manufactured, and organic matter, nitrogen, and phosphorus removal efficiencies of various substrates were measured.

The total volume of the reaction tank of the sewage and wastewater treatment apparatus is 50L (anaerobic tank: 10L, anaerobic tank: 10L, first aeration tank: 20L, second aeration tank: 10L). Anaerobic granular sludge produced an anaerobic granular sludge with an average diameter of 1 mm based on 5 L of anaerobic digestion fluid (MLVSS: 75,000 mg / L, Yongin Sewage Treatment Plant) containing micrococcus microorganisms in a granular sludge production system. 1 Aerobic granular sludge produced 1 mm aerobic granular sludge based on 5L of activated sludge (MLVSS: 2500 mg / L, Yongin Sewage Treatment Plant) containing Acinetobacter microorganism in granular sludge production system. Moreover, the second aerobic granular sludge is nitro consumption eggplant (Nitrosomonas) a microorganism containing activated sludge from the granular sludge production system: the in 1mm, based on (MLVSS 2500 mg / L,, Yong sewage treatment plant) 5L second aerobic granular sludge Nitrified granular sludge was prepared in the granular sludge production system based on 10L of the culture medium containing Nitrosococcus microorganisms of 0.8mm nitrified granular sludge.

The anaerobic granular sludge thus prepared was injected into the anaerobic tank so that the mixed liquid suspended solids (MLSS) concentration was 7,000 mg / L, and the first aerobic granular sludge and the first aerobic granular sludge also had a mixed liquid suspended solids (MLSS) concentration of 7,000 mg / L. It was injected into the anaerobic tank and the first aeration tank so as to be L, respectively. In addition, the nitrified granular sludge was injected into the second aeration tank so that the mixed liquid suspended solids (MLSS) concentration was 3,000 mg / L. As a post-treatment apparatus, a precipitation tank in which the hollow fiber membrane (Econity, ECONITY-102CF) was immersed was installed .

The waste water treatment device manufactured as described above was operated with a hydraulic residence time of 2.5 hours in the reaction tank, and the air injection amount of the first aeration tank and the second aeration tank was adjusted to 12 L / min. The internal circulation rate using the internal circulation pump was twice the inflow flow rate. In this way, 480L of artificial wastewater and actual wastewater were treated per day, and the organic matter, nitrogen and phosphorus removal efficiency and backwash cycle were measured according to the substrate type.

As a result, as shown in Table 1, the biological oxygen demand (BOD5), total nitrogen (TN), and total phosphorus (BN) in treating artificial wastewater and actual wastewater of various substrates using the sewage / wastewater treatment apparatus of the present invention. TP) has been shown to be very efficient in treating wastewater and wastewater.In particular, molasses contains a large amount of hard-decomposable organic substances such as long chain polysaccharides, lignin, and cellulose, which are difficult to break down microorganisms. Although it is difficult to treat biologically, treatment with this wastewater treatment system showed high treatment efficiency. In addition, in the case of treating sewage (wastewater) through the primary sedimentation tank in the Yongin sewage treatment plant using the treatment apparatus of the present invention, biological requirements (BOD ₅ ), total nitrogen (TN) and total phosphorus ( TP) and other wastewater treatment efficiency was high.

On the other hand, the organic matter loading rate of the existing activated sludge process is 0.3 ~ 0.6kg BOD ₅ / day · m ³ (Tom D. Reynolds et al , Unit Operations and Processes in environmental engineering, Wadsworth Publishing Company, 1996) On the other hand, the organic matter loading rate in the sewage and wastewater treatment system of the present invention indicates 2.2 kg BOD ₅ / day · m ³ when the sewage is treated. It was found to be excellent.

division Item BOD ₅ T-N T-P acetate

Influent (mg / L) 300 50 15 Treated water (mg / L) 2 2.1 2.6 Processing efficiency (%) 99.3 95.8 82.6 molasses

Influent (mg / L) 300 50 15 Treated water (mg / L) 6 2.3 3.1 Processing efficiency (%) 98 95.4 79.3 Wastewater

Influent (mg / L) 240 45 12 Treated water (mg / L) 7 4 1.9 Processing efficiency (%) 97.0 91.1 84.1

 The above-mentioned granular sludge and activated sludge (Yongin sewage treatment plant) were respectively injected in the same amount into the sewage and wastewater treatment apparatus of the present invention, and then the backwash cycle of the hollow fiber membrane installed in the sedimentation tank was measured for a long time.

As a result, as shown in Table 2, the sewage and wastewater treatment apparatus of the present invention filled with granular sludge was about 8 times longer in backwash cycle than the treatment apparatus in which activated sludge was injected. When granular sludge is used as in the sewage and wastewater treatment apparatus of the present invention, since the movement of granular sludge is suppressed by the separator plate in each reaction tank, organic matters are decomposed and oxidized only on the surface of suspended solids and granular sludge contained in the influent. As a result, suspended sludge from which newly produced particles are released flows into the settling tank. Therefore, the sewage and wastewater treatment apparatus of the present invention using granular sludge has a lower concentration of mixed liquid suspended solids (MLSS) in the sedimentation tank than the case of using activated sludge, and the suspended sludge separated from the granular sludge also has better SVI than ordinary activated sludge. As a result, the backwash cycle was long.

Item Granular sludge filling Activated sludge filling Backwash Cycle (Days) 8 One

 Therefore, the sewage and wastewater treatment apparatus using the granular sludge according to the present invention is characterized in that the anaerobic granular sludge oxidizes and releases hardly decomposable organic matter from the anaerobic tank, and decomposes and denitrates the organic matter by the first aerobic granular sludge in the anaerobic tank. The organic matter oxidation, nitrification by the aerobic granular sludge, and the nitrification by the nitrification granular sludge in the second aeration tank showed high sewage treatment efficiency.

In addition, even when the membrane is installed in the sedimentation tank as described in the present invention, the separation liquid suspended solids (MLSS) in the sedimentation tank and the suspended sludge SVI separated from the granular sludge are superior to those of the general activated sludge. Could be significantly reduced.

Example  2: granularity of sewage and wastewater treatment apparatus according to the present invention Sludge  Stability measurement

Granular sludge was collected every month while the sewage and wastewater treatment apparatus of Example 1 was operated for 5 months, and the Integrity coefficient (%) of the granular sludge was measured. The measuring method measured the weight of the collected granular sludge, and then rotated for 5 minutes at 200rpm in a jar-tester ((WiseStir ^® ), and then filtered by filtering the remaining granular sludge after completion of the rotation, the weight was measured Integrity coefficient (%) was measured by dividing the granular sludge weight by the total granular sludge weight in percent.

As a result, as shown in Table 3, the Integrity coefficient (%) of the initial granular sludge used in the sewage and wastewater treatment apparatus of Example 1 was found to be 99%, and even after 5 months, the average was 94% or more. Indicated. Therefore, it was found that there is no problem in the morphological change and stability of the granular sludge even after long-term operation of the sewage and wastewater treatment apparatus characterized by injecting the manufactured granular sludge.

As described above in detail specific parts of the present invention, it will be apparent to those skilled in the art that these specific descriptions are merely preferred embodiments, and thus the scope of the present invention is not limited thereto. will be.

5: anaerobic tank 6: anaerobic granular sludge
10: anoxic tank 11: first aerobic granular sludge
15: First Abandonment 16: Second Aerobic Granular Sludge
20: Second Abandonment 21: Nitrified Granular Sludge
25: sedimentation tank 26: separation membrane
30: internal circulation 31: internal circulation pump
a: air supply s: separator
t: stirrer

Claims (12)

Sewage and wastewater treatment apparatus using granular sludge, including:
An anaerobic tank filled with anaerobic granular sludge, equipped with a stirrer for stirring the anaerobic granular sludge, and performing phosphorus discharge and organic matter removal of sewage and wastewater introduced from the outside;
An anoxic tank filled with a first aerobic granular sludge and equipped with a stirrer to stir the aerobic granular sludge to perform denitrification and organic matter removal of the treated water in the anaerobic tank;
A first aeration tank filled with a second aerobic granular sludge and equipped with an air supply unit for supplying air, and performing nitrification, organic matter oxidation and phosphorus excess intake of the treated water treated in the anoxic tank;
A second aeration tank filled with nitrified granular sludge and equipped with an air supply unit for supplying air, and performing nitrification, organic matter oxidation and phosphorus excess intake of the treated water treated in the first aeration tank;
A settling tank in which a separator is immersed to separate and discharge the floating microorganisms contained in the treated water treated in the second aeration tank; And
An internal circulation unit is provided with an internal circulation pump for circulating the treated water treated in the second aeration tank to the anoxic tank.
The method of claim 1, wherein the anaerobic tank, anoxic tank, the first aeration tank and the second aeration tank are each provided with a separation plate mounted on one side spaced apart from the bottom of each reaction tank to prevent granular sludge movement between the reaction tank. Anaerobic tank, anaerobic tank, the first aeration tank and the second aeration tank is a sewage and wastewater treatment apparatus, characterized in that two or more separation plates are provided.
delete The wastewater and wastewater treatment apparatus according to claim 1, wherein the anaerobic granular sludge has an average diameter of 0.5 to 2 mm and contains anaerobic microorganisms.
The sewage and wastewater treatment apparatus according to claim 1, wherein the first aerobic granular sludge and the second aerobic granular sludge have an average diameter of 0.5 to 1 mm and contain aerobic microorganisms or breathable anaerobic microorganisms.
The sewage and wastewater treatment apparatus according to claim 1, wherein the nitrified granular sludge has an average diameter of 0.5 to 1 mm and contains 30 to 70% of aerobic autotrophic microorganisms.
The wastewater treatment apparatus according to claim 6, wherein the aerobic autotrophic microorganism is Nitrosomonas or Nitrobacter .
The sewage and wastewater treatment apparatus according to claim 1, wherein the anaerobic granular sludge, the first aerobic granular sludge and the second aerobic granular sludge are filled at 2,000 to 30,000 mg / L.
The sewage and wastewater treatment apparatus according to claim 1, wherein the nitrified granular sludge is filled at 2,000 to 7,000 mg / L.
A sewage and wastewater treatment method using the sewage and wastewater treatment apparatus of any one of claims 1, 2 and 4 to 9, comprising the following steps:
(a) introducing wastewater and wastewater into an anaerobic tank filled with anaerobic granular sludge to perform dephosphorization and organic matter removal;
(b) introducing the treated water from which dephosphorization and organics have been removed into an anaerobic tank filled with first aerobic particulate sludge to perform denitrification and organics removal;
(c) introducing the treated water from which denitrification and organic matter is removed into a first aeration tank filled with a second aerobic particulate sludge to perform nitrification, organic matter oxidation and phosphorus excess ingestion;
(d) flowing untreated water from the first aeration tank into a second aeration tank filled with nitrifying granular sludge to redo nitrification, organic matter oxidation and phosphorus excess intake;
(e) separating and discharging the floating microorganisms by introducing the treated water treated in the second aeration tank into the settling tank; And
(f) transfer the treated water treated in the second aeration tank to an anaerobic tank using an internal circulation pump, and then repeat steps (b), (c), (d) and (e) to carry out the wastewater. Removing organics, nitrogen and phosphorus.

The method of claim 10, wherein the anaerobic granular sludge, the first aerobic granular sludge and the second aerobic granular sludge are filled at 2,000 to 30,000 mg / L.
The sewage and wastewater treatment method according to claim 10, wherein the nitrified granular sludge is filled at 2,000 to 7,000 mg / L.

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