KR101272016B1 - Wastewater Treatment Apparatus Using Biofilm and Aerobic 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 a biofilm and aerobic granule sludge, and more particularly, to a bioreactor and aerobic granule sludge in a single reactor, and to remove organic matter, nitrogen and phosphorus through internal circulation. The present invention relates to a sewage and wastewater treatment apparatus and method using biofilm and aerobic granule sludge which have greatly improved efficiency.
The sewage / wastewater treatment apparatus using the biofilm and aerobic granule sludge according to the present invention can introduce aerobic granule sludge which has not been introduced in the existing advanced treatment to the upper part of the reaction tank, and thus it is possible to remove organic matter stably even when an instantaneous organic impact load occurs. The sludge clusters present in each layer in the granule sludge facilitate the nitrification and denitrification, and the high sedimentation of the granulated sludge enables the solid-liquid separation in a short time. Additional equipment according to the facilities and treatment functions can be significantly reduced to reduce the equipment and maintenance costs, and by combining with the biofilm in the lower part of the reactor can maximize the removal efficiency of organic matter, phosphorus and nitrogen.

Description

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

The present invention relates to a sewage and wastewater treatment apparatus and method using a biofilm and aerobic granule sludge, and more particularly, to a bioreactor and aerobic granule sludge in a single reactor, and to remove organic matter, nitrogen and phosphorus through internal circulation. The present invention relates to a sewage and wastewater treatment apparatus and method using biofilm and aerobic granule sludge which have greatly improved efficiency.

Recently, the Ministry of Environment promoted the sewage treatment plant upstream of multipurpose dams to increase the sewerage rate of up to 15 multipurpose dams up to 75.2% (27.4% as of 2001). In 2007, a total of KRW 889 billion was invested in sewage treatment areas, including sewage facilities and village sewers.In terms of strengthening the discharged water quality standards, the discharged water quality standards of total phosphorus (TP) and total nitrogen (TN) were released from January 1, 1996. Beginning as regulated by the Environmental Conservation Act, strengthening nationwide with BOD 10 mg / L, COD 40 mg / L, SS 10 mg / L, TN 20 mg / L, and TP 2 mg / L from January 1, 2008 (Environmental White Paper, 2007).

 Most sewage and wastewater treatment plants currently in operation have been designed and operated using activated sludge methods that focus on organic matter and solids. However, the strengthened legislation focuses on the advanced treatment process in addition to organic matters. Currently, the advanced treatment process is being installed in Korea. However, the advanced treatment facilities in operation have many foreign methods and installed low C / N. It is often unsuitable for domestic sewage treatment with rain, and even in the case of wastewater, it is difficult to treat it according to the discharged water quality standards.

In addition, when examining the current status of Korea's sewage treatment method, continuous flow type advanced treatment method is mainly applied to large sewage treatment plants, and SBR technology for the purpose of elastic response of inflow flow in small and medium scale. This is being applied a lot, and the method using a contact agent is also being applied a lot. The continuous flow sewage treatment methods such as A / O or A2 / O are differentiated according to the target materials to be treated. In Korea, many methods for removing nitrogen and phosphorus simultaneously have been developed and applied.

However, unlike other countries, in Korea, the C / N ratio, which is the ratio of organic matters required for nitrogen and phosphorus removal, is low, which makes it difficult to operate the development process efficiently. In particular, when foreign technologies developed in Korea are introduced and applied. However, the technical review, such as the change of design parameters, is not sufficient in advance, so the desired effect is not achieved.

In addition, since most of these methods are biological advanced treatment methods using suspended microorganisms, 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.

Thus, in order to solve such disadvantages of suspended microorganisms in Korea, an immersion type membrane separation process (MBR) has been applied to replace the solid-liquid separation by gravity settling with membrane separation and increase the concentration of microorganisms in the reactor to improve treatment efficiency. . Since the immersion membrane separation process directly immerses the membrane module in the aeration tank, the use of the circulation pump and the settling tank is unnecessary, and the air bubbles supplied through the acid pipes provide oxygen to the microorganisms and cause upward flow at the same time, thereby causing shear stress on the surface of the membrane. Add to prevent contamination of the membrane. Filtrate is obtained by depressurizing the effluent using a suction pump, which is usually operated under a membrane penetration pressure of 0.5 bar or less.

However, immersion type membrane separation process also needs to replace the membrane periodically due to the membrane fouling phenomenon according to the membrane permeation time as in the conventional membrane separation process. The concentration is maintained, which results in high energy consumption. In addition, due to the strengthening domestic environmental regulations, immersion type membrane separation methods are being applied to a relatively small site and stable processing efficiency. In addition, the company is faced with the task of establishing technology development to solve economical aspects of membrane contamination prevention technology, system design and operation technology.

Accordingly, the present inventors have made efforts to solve the problems of the prior art, forming an anaerobic and anoxic region equipped with a biofilm in the lower part of the reactor so that the phosphorus is released first when the sewage and wastewater is injected, the organic material oxidation, nitrification on the upper part of the reactor And forming an aerobic region into which the aerobic granule sludge is injected so that excess phosphorus ingestion is performed, and then the sewage / waste water in which the organic material oxidation, phosphorus excess intake and nitrification is performed is introduced into the lower part of the reaction tank in the anaerobic and anaerobic region through denitrification. And when the phosphorus discharge is performed, not only does it improve the removal efficiency of organic matter, nitrogen and phosphorus contained in sewage and wastewater, but also enables smooth solid-liquid separation to facilitate the post-treatment process operation and minimize the volume of the device. It confirmed and completed this invention.

The main object of the present invention is to facilitate the after-treatment process to facilitate the separation of solid-liquid liquid, and to significantly reduce the equipment and maintenance costs by reducing the additional equipment according to the mechanical equipment and processing functions compared to the conventional SBR method, organic matter, The present invention provides a sewage and wastewater treatment apparatus and method using biofilm and aerobic granule sludge that can improve nitrogen and phosphorus treatment efficiency.

The present invention is a transport pump for introducing the waste water into the device through the inlet pipe; The anaerobic and anoxic states are maintained so that dephosphorization and denitrification of the sewage and wastewater introduced from the transfer pump is carried out, and a biofilm unit and a biofilm unit equipped with a return pump for returning the treated water from the biofilm and biofilm to the lower biofilm And an aerobic state is maintained to perform nitrification, organic matter oxidation, and phosphorus excess ingestion of the treated water treated in the biofilm unit, and filled with aerobic granule sludge therein, and installed in a vertical direction on a separator plate and a separator plate. A reaction tank having an aerobic granule sludge unit equipped with a membrane device connected to an inclined plate and a discharge pump installed at a predetermined distance; An air supply unit for injecting air upward into the aerobic granule sludge portion of the reactor; It provides a sewage and wastewater treatment apparatus using a biofilm and aerobic granule sludge including an internal circulation pump for circulating the treated water treated in the aerobic granule sludge portion of the reactor to the biofilm portion of the reactor.

The present invention also comprises the steps of: (a) through the transfer pump to remove the wastewater into the biofilm part of the anaerobic and anoxic state to perform dephosphorization; (b) passing the dephosphorized treated water through a biofilm to perform denitrification using denitrification microorganisms attached to the biofilm; (c) introducing the denitrified treated water into the aerobic granule sludge and performing nitrification, organic material oxidation and phosphorus excess intake using the aerobic microorganisms contained in the aerobic granule sludge; (d) circulating the nitrified, organic material oxidized and phosphorus-ingested treated water to the biofilm part to perform dephosphorization and denitrification; And (e) repeatedly performing steps (b), (c), and (d) to remove organic matter, nitrogen, and phosphorus from the sewage and wastewater, using the sewage and wastewater treatment apparatus. Provide a treatment method.

The sewage / wastewater treatment apparatus using the biofilm and aerobic granule sludge according to the present invention can introduce aerobic granule sludge which has not been introduced in the existing advanced treatment to the upper part of the reaction tank, and thus it is possible to remove organic matter stably even when an instantaneous organic impact load occurs. The sludge clusters present in each layer in the granule sludge facilitate the nitrification and denitrification, and the high sedimentation of the granulated sludge enables the solid-liquid separation in a short time. Additional equipment according to the facilities and treatment functions can be significantly reduced to reduce the equipment and maintenance costs, and by combining with the biofilm in the lower part of the reactor can maximize the removal efficiency of organic matter, phosphorus and nitrogen.

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

The present invention in one aspect, the transfer pump for introducing the waste water into the device through the inlet pipe; The anaerobic and anoxic states are maintained so that dephosphorization and denitrification of the sewage and wastewater introduced from the transfer pump is carried out, and a biofilm unit and a biofilm unit equipped with a return pump for returning the treated water from the biofilm and biofilm to the lower biofilm And an aerobic state is maintained to perform nitrification, organic matter oxidation, and phosphorus excess ingestion of the treated water treated in the biofilm unit, and filled with aerobic granule sludge therein, and installed in a vertical direction on a separator plate and a separator plate. A reaction tank having an aerobic granule sludge unit equipped with a membrane device connected to an inclined plate and a discharge pump installed at a predetermined distance; An air supply unit for injecting air upward into the aerobic granule sludge portion of the reactor; It relates to a sewage and wastewater treatment apparatus using an aerobic granule sludge and a biofilm comprising an internal circulation pump for circulating the treated water treated in the aerobic granule sludge portion of the reactor to the biofilm portion of the reactor.

More specifically, the sewage and wastewater treatment apparatus using the biofilm and aerobic granule sludge according to the present invention utilizes the dissolved oxygen distribution according to the depth of the reaction tank, the anaerobic and anaerobic regions composed of the biofilm portion, and the aerobic region composed of the aerobic granule sludge portion. , Technology to maximize the treatment of nitrogen, phosphorus and organic matter contained in sewage and wastewater, and forms anaerobic and anoxic regions in the lower part of the reactor, that is, biofilm, so that phosphorus is discharged first when injecting sewage and wastewater. The aerobic granule sludge is injected to form an aerobic zone for organic matter oxidation, nitrification and phosphorus overingestion, and the sewage and wastewater are internally discharged to denitrate and dephosphorize organic and organic wastewater. By circulating, it meets domestic sewage characteristics with low organic matter concentration. The additional facilities according to the treatment function can be reduced to reduce the equipment and maintenance cost.

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

As shown in FIG. 1, the sewage and wastewater treatment apparatus using the biofilm and aerobic granule sludge according to the present invention includes a transfer pump 5, a reaction tank 10, an air supply unit 25, and an internal circulation pump 30. .

In the present invention, the transfer pump 5 is for supplying the waste water and waste water into the reaction tank 10 by a predetermined amount, and the waste water supply pipe 6 on the discharge side of the waste pump of the transfer pump 5. The connection is installed so that the end of the inlet pipe 6 is located in the lower portion of the reaction tank (10).

The reaction tank 10 is maintained in an anaerobic and anoxic state so that dephosphorization and denitrification of the wastewater introduced from the transfer pump is performed, and the biofilm unit 11 and the biofilm unit having the biofilm 15 mounted therein ( Separation plate 42 is maintained in the aerobic state to the nitrification, organic matter oxidation and phosphorus excess intake of the treated water treated in 11), the aerobic granule sludge 20 is filled inside, and installed in a vertical direction, It includes an aerobic granule sludge portion 12 is equipped with a membrane device 40 is connected to the inclined plate 43 and the discharge pump 41 is provided at a predetermined distance above the separation plate.

In addition, a detection sensor unit (not shown) for detecting dissolved oxygen concentration (DO), hydrogen ion concentration (pH), redox potential (ORP), water level meter (WLG), and temperature in the reaction tank 10 and the detection therein. According to the detection signal generated by the sensor unit (not shown) may be provided with a control unit (not shown) for controlling the transfer pump 5, the air supply unit and the internal circulation pump to be described later. The control unit combines a variety of data sensed by the detection sensor unit in a micro-process transfer pump (5) through a power line communication (Power Line Communication, PLC) control device in accordance with the treatment state of the waste water of the reactor 10, It is configured to automatically control the air supply unit 25 and the internal circulation pump 30 and the like.

In the present invention, the biofilm unit 11 includes a biofilm 15, which is a microbial carrier which is installed spaced apart from the bottom of the reactor 10 at a predetermined interval, and a predetermined space under the biofilm 15, Predetermined space of the reaction tank in which the biofilm 15 is separated is maintained in the anaerobic state of dissolved oxygen of 0.1 ppm or less by the depth of the reactor 10, and the region in which the biofilm is mounted is 0.1 ppm to 1 ppm in the absence of oxygen. Is maintained.

Therefore, the predetermined space of the reaction tank in which the biofilm is spaced is maintained in the anaerobic state to perform dephosphorization reaction of sewage and wastewater, and denitrification reaction is performed by denitrification microorganisms attached to the biofilm in the biofilm.

The biofilm 15 is a wastewater of the wastewater introduced into the reaction tank 10 is treated physically by the carrier itself and biologically by a microorganism attached to the surface of the carrier like a membrane. The microorganisms attached to the carrier surface is a high concentration of anaerobic, such as microcode kusu (Micrococcus), Pseudomonas (Pseudomonas), O Como bakteo (Archomobacter), Bacillus (Bacillus), para cock kusu (Paracoccus), acetonitrile tumefaciens (Acetobacterium) Microorganisms, preferably denitrifying microorganisms.

Such anaerobic microorganisms can be intensively treated by long-term contact with hardly decomposable substances. As a result, the decomposition ability of the anaerobic microorganism to the refractory material is enhanced, and the refractory material is rapidly decomposed as a result. In particular, since the anaerobic microorganism is more sticky than the floating, the anaerobic microorganism can be maintained at a high concentration more efficiently than when the carrier is used.

In addition, since denitrification due to the growth of anaerobic microorganisms can be induced, nitrate nitrogen can be removed, organic acids can be generated in the digestion process of the degradable organic material and utilized as an organic source, There are advantages.

The carrier is a stationary phase, and the material is not limited to the present invention, and those known in the art are used. Typically, polyvinyl chloride, polyether, polyethersulfone, polyfluoride vinyl laden, polytetrafluoroethylene, ceramics and the like are possible.

In general, organic matter is not only released when nitrogen nitrate (NO _X _N) is released (denitrified) into nitrogen (N ₂ ) gas, but also phosphorus accumulating microorganisms are accumulated in the form of poly-β-hydroxybutyl acid (PHB). As it is necessary to release phosphorus, it is important that organic matters act as an important factor in the removal of nitrogen and phosphorus contained in sewage, and it is important to properly distribute the limited organic matter to denitrifying microorganisms and condensing microorganisms.

In addition, when there is a competition between the accumulation of microorganisms and denitrification microorganisms denitrifying microorganisms are relatively dominant species intake of organic matter first compared to the accumulation of microorganisms. Therefore, it is necessary to reduce the interference of toxic nitrates of nitrate nitrogen by supplying the limiting organisms to the accumulating microorganisms as soon as possible so that simultaneous treatment of nitrogen and phosphorus can occur by activating the action of the weaker accumulating microorganisms compared to the denitrifying microorganisms. do.

Thus, the sewage and wastewater treatment apparatus using the biofilm and aerobic granule sludge according to the present invention is to install the biofilm 15 in the lower portion of the reactor 10 to supply the limited organic matter to the microorganisms as early as possible, By reducing the interference of the toxic inducing substances to activate the activity of the weaker microorganisms relatively weaker than the denitrifying microorganisms, and to maintain a high mixed solution suspended solids (MLSS) concentration by the adherent microorganisms fixed to the carrier to be described later aerobic granule sludge (20) ) Is designed to facilitate the simultaneous treatment of nitrogen and phosphorus.

In the present invention, the aerobic granule sludge part 12 is treated with water from the biofilm part 11 and air is supplied from the outside to maintain an aerobic state of dissolved oxygen concentration of 3 ppm or more, phosphorus excess intake, nitrification reaction and organic matter The oxidation reaction is carried out, the aerobic granule sludge 20 is injected therein.

The aerobic granule sludge 20 is an aerobic microorganisms contained in activated sludge due to biological, physical, and chemical factors, etc. without expensive carriers, rotating bodies, etc., which are self-immobilized with each other and are granulated with one another. Floating by air supplied upward from (25), organic matter oxidation, nitrification and excess intake of phosphorus in sewage and wastewater are carried out.

The breathable granules of aerobic microorganisms contained in the sludge 20 can be used without limitation so long as it is used in the art, preferably nitro consumption eggplant (Nitrosomonas), nitro vector (Nitrobacter), komaen Pseudomonas (Comamonas), Plastic beam Aerobic and breathable anaerobic microorganisms such as Bacterium ( Flavobacterium ) and Dysgonomonas can be used.

The average diameter of the aerobic granule sludge 20 is 1 ~ 3mm, if the average diameter of the aerobic granule sludge 20 is less than 1mm may blockage on the surface of the immersion membrane, the average diameter exceeds 3mm In this case, the structure of the aerobic granule sludge may be weakened due to organic matter restriction inside the aerobic granule sludge.

In addition, in the present invention, the amount of filling the aerobic granule sludge 20 in the reaction tank 10 is adjusted by the control according to the concentration of the mixed liquid suspended solids (MLSS) of the reaction tank. Preferably it can be filled to 2,000 to 7,000 mg / L. This problem occurs when the concentration of the mixed liquid suspended solids (MLSS) of the reaction tank filled with aerobic granule sludge 20 is less than 2,000 mg / L, and organic matters are not removed and nitrified, and the concentration of the mixed liquid suspended solids (MLSS) is increased. If it exceeds 7,000 mg / L there is a problem that the aerobic granule sludge structure is weakened due to the lack of organic matter.

In the present invention, as the aerobic granule sludge is already granulated, it is possible to maintain a high concentration of aerobic microorganisms in the reactor as it is injected into the reactor (10), so that it can maintain strong resistance to the impact load of organic matter, and thus a sedimentation tank (not shown). As well as the management of the suspended sludge in the back, it is possible to smooth the solid-liquid separation to minimize the size of the settling tank (not shown), it can also solve the problem of membrane clogging of the membrane separation process that can be used as an alternative to the settling tank.

In addition, the aerobic granule sludge is activated in a rich state in the reaction tank to increase the homogeneity of the aerobic microorganisms to quickly remove the remaining organic matter and at the same time increase the efficiency of nitrification and excess intake efficiency of phosphorus.

In the present invention, the air supply unit 25 is installed on the upper portion of the biofilm 15, a plurality of aeration nozzles 26 and the aeration nozzle for injecting air toward the upper portion of the reaction tank 10 filled with aerobic granule sludge 20 It includes an air supply unit 27 for supplying air to the plurality of aeration nozzles (26).

The air supply unit 25 injects air toward the upper portion of the reaction tank 10 in which the aerobic granule sludge 20 is filled, so that aerobic conditions are performed on the upper portion of the reaction tank in which the aerobic granule sludge 20 is filled to perform organic material oxidation and nitrification. At the bottom of the biofilm, dissolved oxygen concentration is controlled to 0.2 ppm or less to maintain anaerobic and anaerobic conditions. At this time, the air supply unit 25 injects air into the aerobic granule sludge at 4 ~ 7L / min. If air is injected at less than 4L / min, the granule structure is weakened due to lack of shear force at the aerobic granule sludge surface, and if it is injected at more than 7L / min, the operating cost increases due to high energy consumption. Can be.

In the present invention, the internal circulation pump 30 is installed in the upper portion of the reactor 10 to circulate the organic matter oxidized and nitrified supernatant to the anaerobic and anoxic region of the lower portion of the reactor through the transfer pipe (31). In this case, the internal circulation of the supernatant is performed according to the detection signal of the detection sensor unit (not shown) after measuring the dissolved oxygen concentration, the redox potential, etc. in the upper and lower portions of the reactor using the above-described detection sensor unit.

The sewage and wastewater treatment apparatus using the biofilm and aerobic granule sludge according to the present invention may include a conveying pump 35 for conveying the treated water nitrified by the aerobic granule sludge 20 to the biofilm lower region.

In addition, the sewage and wastewater treatment apparatus using the biofilm and aerobic granule sludge according to the present invention is provided with a membrane device 36 or a precipitation tank (not shown) such as a hollow fiber membrane or a flat membrane at the top or the rear end to discharge the supernatant treated in the reaction tank. It is possible to minimize the volume of the whole sewage and wastewater treatment device.

In another aspect, (a) performing the dephosphorization by introducing sewage and wastewater into the biofilm part of the anaerobic and anoxic state through the transfer pump; (b) passing the dephosphorized treated water through a biofilm to perform denitrification using denitrification microorganisms attached to the biofilm; (c) introducing the denitrified treated water into the aerobic granule sludge and performing nitrification, organic material oxidation and phosphorus excess intake using the aerobic microorganisms contained in the aerobic granule sludge; (d) circulating the nitrified, organic material oxidized and phosphorus-ingested treated water to the biofilm part to perform dephosphorization and denitrification; And (e) repeatedly performing steps (b), (c), and (d) to remove organic matter, nitrogen, and phosphorus from the sewage and wastewater, using the sewage and wastewater treatment apparatus. It relates to a treatment method.

Referring to the operation and action of the sewage and wastewater treatment apparatus according to the present invention configured as described above are as follows.

The sewage / wastewater treatment apparatus using the biofilm and aerobic granule sludge according to the present invention first discharges the sewage / wastewater to the lower portion of the reactor in the anaerobic state with a transfer pump 5 to release phosphorus preferentially, and then enters the biofilm in the anaerobic state. After inducing denitrification, the denitrified treated water passes through the biofilm 15 to perform organic oxidation, nitrification and excess ingestion of phosphorus in the aerobic granule sludge 20 region in aerobic state.

The treated water, which has been subjected to organic matter oxidation, nitrification and phosphorus overingestion, is recycled back to the biofilm portion of the reaction tank 10 through the internal circulation pump 30 to release denitrification and phosphorus from the anaerobic and anaerobic regions equipped with the biofilm 15. This is done, and this process occurs repeatedly to efficiently remove organics, nitrogen and phosphorus.

The sewage and wastewater treatment apparatus using the biofilm and aerobic granule sludge of the present invention is first introduced into the lower portion of the reaction tank 10 in the anaerobic and anaerobic tank state, and the organic matter by the smooth supply of the organic matter of the introduced sewage and wastewater. It increases the dephosphorization efficiency by activating the activity of phosphorus accumulation microorganisms, and forms a strong growth condition of the microorganisms attached to the biofilm.

In other words, phosphorus compounds (in the state of acetic acid ions) in the influent sewage and wastewater pass through anaerobic and anoxic biofilms (15) and accumulate microorganisms (PAOs, phosphate accumulating organisms, The main dominant species of PAOs are diffused and moved into the cells of acinetobacter, using acetyl coenzyme (AcCoA, Acetyl) by using the energy (ATP) generated by the degradation of intracellular phosphate polymers (Poly-P, Poly-phosphate) in the anaerobic state. is changed to -CoA), active phosphate ions (P while AcCoA is through the TCA (tricarboxylic acid) Cycle stored in a state PHB (Poly-β- hydroxybutyrate) ^- emits a).

The sewage and wastewater which floated to the upper part of the biofilm through the process as described above is formed by excessive intake of phosphorus, nitrification and organic oxidation by the aeration and aerobic granule sludge 20 of the air supply unit 25. The organic material oxidation is obtained by actively decomposing organic matter by aerobic microorganisms contained in aerobic granule sludge and sewage and wastewater in the reaction tank to obtain energy, and by synthesizing the organic matter in sewage and wastewater, new cells of microorganisms (C ₅ H ₇ O ₂ N), are removed is converted to CO ₂ and the like. 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 the following formula.

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

In addition, the nitrification reaction in the aerobic region is performed by aerobic microorganisms ( Nitrosomonas ) containing organic nitrogen (Nan 3) and ammonia nitrogen (NH ₃ -N) contained in sewage and wastewater in aerobic granule sludge. and nitro vector (Nitrobacter), autotrophic aerobic microorganisms (aerobic Autotrophic Bacteria )] is converted into NH ₃ -N by the decomposition action. NH ₃ -N is converted to nitrate nitrogen (NO ₃ -N) via nitrite nitrogen (NO ₂ -N) by a 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 aerobic granule sludge in the aerobic region of the reactor 10 ingest the phosphate ions (orthophosphate) from the outside while decomposing PHB stored in the cell into oxygen in the aerobic state. Poly-phosphate is stored intracellularly. In order to continue supplying the energy source (ATP) necessary for the synthesis process, phosphorus intake by PAOs (the main predominant species of PAOs is Acinetobacter ) increases from the outside. Is removed.

As described above, the treated water in which phosphorus excess intake, organic matter oxidation and nitrification is circulated internally to the biofilm part and is transferred to the reactor in the anaerobic and anoxic state. The decomposition of organic matter by anaerobic microorganisms can be divided into two stages.

In the first step, organic matter is converted into organic acids such as acetic acid (CH ₃ COOH) or lopionic acid (CH ₃ CH ₂ COOH) by organic acid producing bacteria, and in the case of proteins, ammonia (NH ₃ ) is produced in addition to organic acids during decomposition. do.

In the second stage, the organic acid produced in the first stage is converted by the methane producing bacteria into the final products methane and carbon dioxide. Since the growth rate of the organic acid producing bacteria is fast while the growth rate of the methane producing bacteria is slow, the efficiency of wastewater treatment by the anaerobic method depends on the role of the methane producing bacteria rather than the organic acid producing bacteria. Organic matter by methane-producing bacteria is converted to C ₅ H ₇ O ₂ N, CH ₄ , CO ₂ and the like. The decomposition process is expressed as follows.

CHON (organic) + H ₂ O + Nutrients → C ₅ H ₇ O ₂ N + CH ₄ + CO ₂ + NH ₃ + HCO ₃ + Other Products

NO ₃ -N produced by nitrification in the anaerobic region of the reactor is reduced to harmless nitrogen gas (N ₂ ) and released into the atmosphere by the microorganisms of the biofilm which reduces it again. Denitrifying microorganisms are facultative heterotrophic bacteria unlike the nitrification reactions described above. When there is sufficient dissolved oxygen, aerobic autotrophic microorganisms (nitrification microorganisms, nitrous oxide microorganisms, etc.) are predominantly active in obtaining oxygen as an electron acceptor, whereas the denitrifying microorganisms in which oxygen and nitrate are energized as nutrient sources. In order to activate the denitrification, an anoxic environment without oxygen supply and sufficient organic matter are absolutely necessary. Representative denitrifying microorganisms may include microcode kusu (Micrococcus), Pseudomonas (Pseudomonas), O Como bakteo (Archomobacter) and Bacillus (Bacillus). An example of a 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

By repeating anaerobic / aerobic / aerobic / aerobic as described above, nitrogen and phosphorus in the sewage are removed, and the sedimented sludge is rectified in the reaction tank to be discharged through the discharge pump 41, or a sedimentation tank (not shown) at the rear end. Transfer to settle and discharge.

Hereinafter, the present invention will be described in more detail with reference to Examples. It is to be understood by those skilled in the art that these examples are for illustrative purposes only and that the scope of the present invention is not construed as being limited by these examples.

Example  One: Biofilm  And aerobic Granule Sludge  Evaluation of Treatment Efficiency of Used Sewage / Wastewater Treatment System

As shown in FIG. 1, the sewage and wastewater treatment apparatus using the biofilm and aerobic granule sludge according to the present invention was manufactured to evaluate organic treatment efficiency according to various substrates.

The reactor volume of the sewage / wastewater treatment system using biofilm and aerobic granule sludge is 10 l, and 3 l of activated carbon carrier (Lianyungang Jinli Carbon CO. LTD) to which microorganisms such as Pseudomonas are attached is placed 50 mm from the bottom of the reactor. After fixed installation, the anaerobic microorganisms were filled with aerobic granule sludge granulated with sludge containing nitrosomonas ( Nitrosomonas ) on top of the activated carbon carrier.

The biofilm was prepared by inoculating anaerobic sludge containing microorganisms such as Pseudomonas in an anaerobic reactor filled with activated carbon, and then operating for 5 months. The aerobic granule sludge was aerobic The aerobic granule sludge was prepared by inoculating the granule sludge preparation reactor and operating in a continuous batch (injection, granule formation, granule precipitation and supernatant discharge) while injecting wastewater containing ammonia into the aerobic granulation preparation reactor.

The average diameter of the aerobic granule sludge was about 2 mm, the injection amount of the aerobic granule sludge was adjusted to 5,000 mg / L based on MLSS. In the sewage and wastewater treatment apparatus using the biofilm and aerobic granule sludge thus prepared, the hydraulic residence time in the reactor was operated for 2 hours, and the air injection amount was adjusted to 5 L / min. The conveying speed from the upper part of the reactor to the lower part was about three times the inflow flow rate, and the conveyance in the biofilm in the lower part of the apparatus was operated at 0.5 times the inflow flow rate.

120L of artificial wastewater was treated per day by continuous operation in this manner, and various artificial organic matters (acetate, glucose and molasses) were measured as substrates in order to evaluate the organic removal efficiency according to the substrate type.

division Item BOD ₅ T-N T-P acetate

Influent
(mg / L) 250 50 10 Treated water
(mg / L) 5 2.5 2.2 Processing efficiency
(%) 98 95 78 Glucose

Influent
(mg / L) 250 50 10 Treated water
(mg / L) 8 4 2.3 Processing efficiency
(%) 97 92 77 molasses

Influent
(mg / L) 250 50 10 Treated water
(mg / L) 42 2 2.7 Processing efficiency
(%) 90 96 73

As a result, as shown in Table 1, in the treatment of artificial wastewater of various substrates using the sewage and wastewater treatment apparatus of the present invention, such as chemical oxygen demand (BOD), total nitrogen (TN) and total phosphorus (TP) The efficiency of wastewater treatment has been shown to be very good, and in particular, molasses contains a large amount of long-chain polysaccharides, which are difficult to break down microorganisms, and hardly decomposable substances such as lignin and cellulose. When treated using sewage and wastewater treatment system showed high treatment effect.

In addition, the organic loading rate of the conventional 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 apparatus of the present invention is 2.9 kg BOD ₅ / day m ³ when glucose is used as a substrate, resulting in treatment efficiency. Was found to be excellent.

Therefore, the sewage and wastewater treatment apparatus using the biofilm and aerobic granule sludge of the present invention has high wastewater treatment efficiency because the organic matter oxidation, nitrification and phosphorus excess intake by aerobic granule sludge and denitrification and phosphorus release by living organisms are performed smoothly. In addition, the stability of aerobic granule sludge increased during long-term operation. It is believed that the biofilm and aerobic granule sludge are located in one reactor to maintain mutually complementary relationship, thus maximizing organic, nitrogen and phosphorus removal efficiency.

Example  2: Biofilm  And aerobic Granule Sludge  Aerobic Granules of Sewage and Wastewater Treatment System Sludge  Performance Evaluation by Type

In order to evaluate the performance of the hollow fiber membrane according to the type of aerobic sludge, the apparatus was operated under the conditions and the conditions used in Example 1, but the activated carbon carrier having the anaerobic microorganism attached to the bottom of the reactor was removed from the apparatus used in Example 1, and the aerobic granule Performance evaluations were carried out under aerobic conditions using two devices each equipped with sludge or activated sludge. The MLSS of the initial reactor was 5,000mg / L, and the internal transport was not carried out, and the transmembrane hydrostatic pressure was measured by increasing the flux from 20LMH to 70LMH in 10LMH increments and operating for 2 hours in each section to change the transmembrane hydrostatic pressure. Was observed.

Aerobic Granule Sludge Activated sludge TMP (kPa) flux (LMH) TMP (kPa) flux (LMH) 6.3 (6.9) 20 (20) 8.3 (12.4) 20 (20) 10.1 (12.1) 30 (30) 10.5 (18.7) 30 (30) 12.9 (15.2) 40 (40) 17.2 (25.5) 40 (40) 16.5 (17.9) 50 (50) 30.5 (42.5) 50 (50) 20.5 (22.5) 60 (60) 41.6 (87.3) 60 (60) 24.1 (27.1) 70 (70) 52.7 (121) 70 (70)

As a result, as shown in Table 2 above, when the aerobic granule sludge was provided, the hydrostatic pressure was almost constant at each flux value. However, when the activated sludge was used, the hydrostatic pressure rapidly increased with time. Comparing the hydrostatic pressure of aerobic granule sludge and activated sludge in the values, the hydrostatic pressure difference increased as the flux value increased. Therefore, it was found that the use of aerobic granule sludge instead of activated sludge significantly reduced the clogging of the membrane surface at high microbial concentrations.

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: transfer pump 6: inlet pipe
10: reactor 11: biofilm part
12: aerobic granule sludge part 15: biofilm
20: aerobic granule sludge 25: air supply
26: Aeration nozzle 27: Air supply unit
30: internal circulation pump 31: transfer pipe
35: return pump 40: membrane device
41: discharge pump 42: separation plate
43: inclined plate

Claims (7)

Sewage and wastewater treatment apparatus using biofilm and aerobic granule sludge, including:
A transfer pump for introducing sewage and wastewater into the apparatus through an inlet pipe;
The anaerobic and anoxic states are maintained so that dephosphorization and denitrification of the sewage and wastewater introduced from the transfer pump is carried out, and a biofilm unit and a biofilm unit equipped with a return pump for returning the treated water from the biofilm and biofilm to the lower biofilm And an aerobic state is maintained to perform nitrification, organic matter oxidation, and phosphorus excess ingestion of the treated water treated in the biofilm unit, and filled with aerobic granule sludge therein, and installed in a vertical direction on a separator plate and a separator plate. A reaction tank having an aerobic granule sludge unit equipped with a membrane device connected to an inclined plate and a discharge pump installed at a predetermined distance;
An air supply unit for injecting air upward into the aerobic granule sludge portion of the reactor; And
An internal circulation pump for circulating the treated water treated in the aerobic granule sludge portion of the reactor to the biofilm portion of the reactor.
The sewage and wastewater treatment apparatus according to claim 1, wherein the biofilm is mounted to be spaced apart from the bottom of the reactor to form a predetermined space.
The sewage and wastewater treatment apparatus according to claim 1, wherein the aerobic granule sludge has an average diameter of 1 to 3 mm.
The sewage and wastewater treatment apparatus according to claim 1, wherein the air supply unit injects air into the aerobic granule sludge at 4 to 7 L / min.
delete A sewage and wastewater treatment method using the sewage and wastewater treatment apparatus of any one of claims 1 to 4, comprising the following steps:
(a) performing dephosphorization by introducing sewage and wastewater into the biofilm part of anaerobic and anoxic states through a transfer pump;
(b) passing the dephosphorized treated water through a biofilm to perform denitrification using denitrification microorganisms attached to the biofilm;
(c) introducing the denitrified treated water into the aerobic granule sludge and performing nitrification, organic material oxidation and phosphorus excess intake using the aerobic microorganisms contained in the aerobic granule sludge;
(d) circulating the nitrified, organic material oxidized and phosphorus-ingested treated water to the biofilm part to perform dephosphorization and denitrification;
(e) repeatedly performing steps (b), (c) and (d) to remove organic matter, nitrogen and phosphorus from sewage and wastewater; And
(f) maintaining the appropriate settling time after completing step (e), and then discharging the treated supernatant through a membrane device or settling tank.
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