KR100869304B1 - High effective treatment apparatus of sewage and wastewater - Google Patents

Abstract

A high effective processing device for sewage and wastewater is provided to control the nitrogen of processing water to be lower than 5mg/L although C/N ratio within the inflow water is low by processing repetitively the nitrogen within the inflow water, to reduce the size of the processing device for the sewage and wastewater by not having a separate settling pond or a subsequent filtering device, and to minimize an area for the installment of the device. A first anoxic chamber processes the denitrification from the nitric acid nitrogen within the sewage and wastewater. An aeration tank performs the oxidation and nitrification of the organic compound by connecting to the first anoxic chamber. A second anoxic chamber processes additionally the denitrification from the nitric acid nitrogen by connecting to the aeration tank. A membrane separation aeration tank is connected to the second anoxic chamber, oxidizes the residual organism, and separates the processing water and microorganism. A separation film is installed in the membrane separation aeration tank and separates the processing water and sludge. A sludge denitrification tank is installed in the front part of the first anoxic chamber and removes a part nitrate nitrogen and residuary dissolved oxygen. A first conveying line returns an activated sludge in the aeration tank to a sludge denitrification tank. A second conveying line returns the activated sludge in the membrane separation aeration tank to the aeration tank.

Description

Sewage and Wastewater Advanced Treatment System {HIGH EFFECTIVE TREATMENT APPARATUS OF SEWAGE AND WASTEWATER}

The present invention relates to an advanced sewage and wastewater treatment apparatus using an immersion type membrane. Specifically, the present invention repeatedly purifies nitrogen, phosphorus, and organic substances in sewage and wastewater while passing through a first anoxic tank, an aerobic tank, a second anoxic tank, and a membrane separation tank. The present invention relates to an advanced treatment system for sewage and wastewater.

Water is an essential substance that maintains the life of all living things on the earth, and it descends to the surface of the earth through snow or rain through the water cycle. In Korea, rainfall is concentrated according to regions or seasons and is considered a finite resource. The dirty water used and thrown away by humans was cleaned and cleaned up by the self-cleaning action, which is the principle of nature, and returned to the natural world to maintain the ecosystem.However, after the industrial revolution, water pollution became severe due to urbanization and industrial development due to population concentration. Accordingly, there is a growing need for active development of ways to recycle sewage and wastewater economically.

An important point in recycling sewage and wastewater is to treat nitrogen, phosphorus and organic matters, water turbidity, pH, etc. in recycled sewage and wastewater to the required level, and to remove pathogenic microorganisms to ensure environmental engineering stability. I do it.

Nitrogen or phosphorous from agricultural fertilizers, manure or livestock manure, or synthetic detergents can enter the water system, causing eutrophication, coastal red tide, fish toxins in ammonia and dissolved oxygen deficiency in water Increasing chlorine demand and causing health, such as cyanosis, when nitrate nitrogen is present in drinking water at high concentrations. In addition, the algae overgrowth due to the inflow of water sources such as nitrogen and phosphorus may cause unpleasantness in taste and smell of tap water.It may cause clogging of sand filter paper, which is a water purification process. It can create and impair human health.

As such, the inflow of nitrogen and phosphorus into the water system causes problems such as economic loss caused by the increase in the purification cost, difficulty in securing safe and clean water resources for public health, and thus, blocking the inflow of nutrients into the water system is essential. As the most fundamental solution, the treatment of nitrogen and phosphorus as well as the removal of organic matter from sewage, wastewater and livestock wastewater is emphasized more.

For the treatment of nitrogen and phosphorus, a MBR (Membrane Bio-Reactor) process was developed that combines a biological treatment process and a separator for treatment of pathogenic microorganisms and suspended solids.

The conventional MBR process is composed of an anoxic tank for denitrifying nitrate nitrogen using organic matter and an aerobic tank for changing ammonia nitrogen to nitrate nitrogen, and the treated water from which the organic matter is removed through the membrane in the aeration tank is stored in a storage tank. The water in which the sludge is mixed from the aeration tank is returned to the anoxic tank.

In order to remove nitrogen biologically, in most processes, the reaction tank is disposed in the order of anoxic tank and aerobic tank, and the nitrate nitrogen generated in the aerobic tank is transferred to the anoxic tank using an internal conveying pump and piping. Since organic matter in the sewage and wastewater is limited, it is generally returned within 3 to 4 times the flow rate for the further denitrification and the rest is discharged to the treated water.

Since the nitrogen removal rate is greatly influenced by the water temperature of the reactor, the concentration of microorganisms, the characteristics of the influent, the time, the season, etc., it is very difficult to control the nitrogen concentration of the treated water below the regulated level, and therefore, if the temperature exceeds the limit, the anaerobic tank is primarily used. An additional external carbon source is added to the reactor to improve the denitrification rate and to control nitrogen in the aerobic tank to remove nitrogen on a limited basis. However, since the nitrate nitrogen, which is internally returned from the aerobic tank and flows out to the treated water, is essentially limited in nitrogen removal. Therefore, if the influent C / N ratio is very low, or if nitrogen or less than 5mg / L, phosphorus 0.5mg / L or yearly stable treatment is required, the existing nitrogen and phosphorus removal process is difficult to process and additional process is required. And additional operating costs.

The present invention was developed in order to overcome the problems of excess dissolved oxygen in the internal transport line and the limitations of biological nitrogen treatment in the conventional immersion membrane process as described above, by minimizing the amount of air required for the existing aeration tank of the blower equipment It can reduce operating power, treat nitrogen of treated water to the target water quality even if C / N ratio is low, and can achieve high efficiency of removing nitrogen, phosphorus and organic matter without installing additional facilities. It is an object to provide a processing device.

In order to achieve the above object, in the present invention, a biological advanced processing apparatus including an immersion membrane, the first anoxic tank 110 for the denitrification treatment of nitrate nitrogen in sewage and waste water; An aerobic tank 120 connected to the first anoxic tank 110 to perform organic material oxidation and nitrification; A second anoxic tank 130 connected to the aerobic tank 120 for further denitrification of nitrate nitrogen; A membrane separation aeration tank 140 connected to the second anoxic tank 130 to oxidize residual organic matter, nitrification occurs, and solid-liquid separation between the treated water and microorganisms; A separation membrane 150 installed in the membrane separation tank 140 to separate treated water and sludge; A sludge denitrification tank 160 connected to the first anoxic tank 110 to remove some nitrate nitrogen and residual dissolved oxygen; A first conveying line 170 conveying activated sludge in the exhalation tank 120 to the sludge denitrification tank 160; And a second conveying line 180 for conveying activated sludge in the membrane separation breathing tank 140 to the breathing tank 120.

Here, the sewage and waste water are configured to be introduced into the sludge denitrification tank 160 and the first anoxic tank 110 to be introduced.

On the other hand, the mechanism of nitrogen and phosphorus removal in water, nitrogen is present in water in the state of organic nitrogen, such as proteins, amino acids, urea, ammonia nitrogen, nitrite nitrogen and nitrate nitrogen. Organic nitrogen contaminated in water is decomposed into ammonia nitrogen by the action of microorganisms and then oxidized to nitrate nitrogen through nitrite nitrogen.Inorganic microorganisms living in water are inorganic such as ammonia nitrogen, nitrite nitrogen and nitrate nitrogen. Nitrogen is used as a nutrient to multiply. In the present invention, the aerobic tank and the membrane separation aerobic tank are reaction tanks that provide an aerobic environment and decompose ammonia nitrogen into nitrate nitrogen. In the present invention, the first anoxic tank, the second anoxic tank, and the sludge denitrification tank are reaction tanks providing an anaerobic environment, and serve to remove nitrogen by denitrifying nitrate nitrogen.

In water, phosphorus is present in the form of organic phosphorus such as protein, ATP, phosphorous phosphate and polyphosphorus phosphate. Such phosphorus is converted to phosphate in water and used by algae. If the amount is too large, the COD increases due to the overgrowth of algae, causing water pollution. In the present invention, phosphorus is partially removed from the anaerobic environment and membrane separation tank of the first anoxic tank, the second anoxic tank, and the sludge denitrification tank, and most of the phosphorus is removed from the aerobic tank by biological and chemical methods.

As described above, according to the sewage and wastewater advanced treatment apparatus according to the present invention, by repeatedly treating nitrogen in inflow water through the first and second conveying lines, 5 mg / L of nitrogen in the treated water is treated even if the C / N ratio in the inflow water is low. There is an advantage that can be controlled as follows.

In addition, since the configuration of the device does not require a separate sedimentation basin or subsequent filtration device, it is possible to reduce the size of the sewage and wastewater treatment device, thereby minimizing the use site for installing the device.

In addition, to prevent the sludge from adhering to the surface of the separation membrane installed in the membrane separation tank, the excess air injected through the lower acid pipe is returned to the aeration tank together with the activated sludge through the second conveying line to reduce the amount of air introduced into the aeration tank. The operating power of the blower equipment can be reduced.

In addition, nitrate-based microorganisms nitrify using dissolved oxygen in the aeration tank by transporting the membrane separation and aeration tanks through the second transport line, and maximizing denitrification efficiency by transporting the internal transport back to the sludge denitrification tank through the first transport line. Can be planned.

Hereinafter, with reference to the accompanying drawings, the configuration of the sewage and wastewater treatment system according to the present invention will be described in detail.

In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

1 is a conceptual diagram schematically showing the configuration of an advanced sewage and wastewater treatment apparatus according to the present invention.

Referring to FIG. 1, the sewage and wastewater advanced treatment apparatus 100 according to the present invention includes a first anaerobic digestion tank 110, an aerobic tank 120, a second anoxic tank 130, and a membrane separation aeration tank 140. And a separation membrane 150, a sludge denitrification tank 160, a first conveying line 170, and a second conveying line 180.

First, the first anoxic tank 110 denitrates nitrate nitrogen in sewage and wastewater.

In addition, the aerobic tank 120 is connected to the first anoxic tank 110 to cause organic material oxidation and nitrification.

In addition, the second anaerobic tank 130 is connected to the aerobic tank 120 to further denitrate the nitrate nitrogen.

In addition, the membrane separation tank 140 is connected to the second anoxic tank 130 to oxidize residual organic matter, nitrification occurs, and the solid-liquid separation of the treated water and microorganisms occurs.

On the other hand, the separation membrane 150 is installed in the membrane separation tank 140 to separate the treated water and sludge.

The sludge denitrification tank 160 is connected to the first anoxic tank 110 to remove some nitrate nitrogen and residual dissolved oxygen.

In addition, the first conveying line 170 conveys the activated sludge in the aeration tank 120 to the sludge denitrification tank 160.

In addition, the second conveying line 180 conveys the activated sludge in the membrane separation aeration tank 140 to the aeration tank 120.

In addition, the first anaerobic tank 110 may further include a screen tank 102 having a screen 101 for filtering contaminants contained in the sewage and wastewater before the sewage and wastewater is introduced.

In addition, the sewage and wastewater advanced treatment apparatus 100 according to the present invention, the inflow pipe 103 to allow the sewage and wastewater passing through the screen tank 102 to the sludge denitrification tank 160 and the first anoxic tank 110. And an inlet valve 104 for distributing and regulating the inflow water from the inlet pipe 103 to the sludge denitrification tank 160 and the first anoxic tank 110.

The exhalation tank 120 and the membrane separation exhalation tank 140, the blower 105 is connected may be provided with an air dispersing device for supplying oxygen in the exhalation tank 120 and the membrane separation exhalation tank 140, respectively, sludge denitrification tank 160, the first anoxic tank 110 and the second anoxic tank 130 may be provided with a water stirrer 106 to prevent the dead space is formed on one side and the sludge is deposited on the bottom.

Reference numeral 109 in the figure denotes a sludge drawing pump for drawing sludge in the membrane separation tank 140.

Hereinafter, the wastewater and wastewater purification process using the advanced wastewater and wastewater treatment apparatus according to the present invention will be described.

First, the waste water is passed through the screen tank 102 provided with the screen 101. The screen tank 102 is provided with a screen 101 for filtering contaminants such as sand or gravel contained in the sewage and wastewater, and before the first anoxic tank 110 and the sludge denitrification tank 160 are introduced into the sewage and wastewater. It filters out pollutants. The interval of the screen 101 is usually 1 to 2 mm, and the shape or interval of the screen 101 is not limited.

The sewage and wastewater passing through the screen tank 102 flows into the sludge denitrification tank 160 and the first anoxic tank 110 through the inflow pipe 103 and undergoes a treatment process. 2 is introduced into the oxygen-free tank 130 and the membrane separation tank 140 is repeatedly processed. The inflow pipe (103) is configured to flow into the sludge denitrification tank (160) and the first anoxic tank (110) to flow down the waste water passed through the screen tank (102), each inlet pipe (103) The inlet valve 104 is installed to control the amount of wastewater flowing in.

In addition, in the present invention, the sludge denitrification tank 160 may be provided with a water level measurement sensor 107 for measuring the water level, the water level value measured by the water level measurement sensor 107 and a predetermined level value A control unit (not shown) is further provided to control the inflow valve 104 installed on the inflow pipe 103 to adjust the quantity of sewage and wastewater flowing into the first anoxic tank 110 and the sludge denitrification tank 160. Can be.

When the wastewater is introduced into the first anoxic tank 110 through the screen tank 102, the first anoxic tank 110 decomposes and treats the nitrate nitrogen with nitrogen gas using a carbon source in the wastewater. The denitrification process removes nitrogen.

In addition, in order to lower the residual dissolved oxygen concentration contained in the first conveying line 170, the nitric acid nitrogen conveyed in the aerobic tank 120 is denitrified in the first anoxic tank 110 through the sludge denitrification tank 160. Also, the oxidation reaction of some organic substances occurs, whereby most of the organic substances are removed through the first anoxic tank 110 and the aerobic tank 120. At this time, it is preferable to install an underwater stirrer 106 in the dead space formed in the first anaerobic tank 110 and the first anaerobic tank 110 to prevent the lower deposition of the sludge.

In the aerobic tank 120, untreated water is introduced from the first anoxic tank 110, and in the aerobic tank 120, a reaction in which the organic matter in the untreated water is oxidized and a nitrification reaction in which ammonia nitrogen is converted to nitrate nitrogen occur simultaneously.

In addition, a phosphorus removal reaction occurs in the aerobic tank 120, and biologically removes phosphorus using microorganisms in untreated water, and if the phosphorus concentration in the untreated water does not reach the target concentration by only such a biological method, the aerobic tank 120 The target water quality can be achieved by injecting a flocculant directly into the chemical to remove phosphorus.

In addition, the blower tank 120 is connected to the blower 105 is provided with an air diffuser for supplying oxygen in the exhalation tank 120, the bubble generated in the air blower connected to the blower 105 is an aerobic tank 120 It supplies a dissolved oxygen in the role to promote the nitrification reaction.

The untreated water treated in the aerobic tank 120 flows into the second anoxic tank 130. Since the second anoxic tank 130 removes nitrate nitrogen introduced from the aerobic tank 120 using endogenous denitrification or an external carbon source, the nitrogen concentration of the treated water may be controlled according to the input amount of the external carbon source. In this case, as in the first anaerobic tank 110, the second anaerobic tank 130 is also provided with an underwater stirrer 106 to prevent the dead space from being formed and to be deposited under the sludge second anaerobic tank 130. It is preferable.

As such, by providing the second anoxic tank 130 connected to the aerobic tank 120, it is possible to additionally denitrate the nitrate nitrogen that was not removed from the first anoxic tank 110, it is possible to remove nitrogen with high efficiency.

The untreated water denitrated in the second anoxic tank 130 flows into the membrane separation tank 140.

In the membrane separation tank 140, a separation membrane 150 having a plurality of micro membranes is installed, and the inflow water passes from the lower portion of the separation membrane 150 to the upper portion thereof to filter particulate matter in the water by the micro membrane. Additional organic removal reactions and nitrification and dephosphorization reactions occur.

The upper part of the separation membrane 150 is provided with a filtration pump 108 for moving the treated water passing through the separation membrane 150 to the treated water tank through the outlet pipe.

In this case, an air diffuser may be installed at the bottom of the membrane separation tank 140 or at the bottom of the separation membrane 150. The diffuser device is connected to the blower 105, and serves to promote the nitrification reaction by supplying dissolved oxygen by generating bubbles in the membrane separation tank 140. In addition, the sludge is prevented from adhering to the membrane surface of the separator 150 while passing from the bottom of the separator 150 to the top. The blower 105 connected to the membrane separation tank 140 may be connected to the blower 105 connected to the exhalation tank 120 in the same line or in a plurality of lines.

As described above, the raw water of the membrane separation tank 140 is conveyed to the aeration tank 120 through the second conveying line 180. By returning the excess dissolved oxygen generated in the membrane separation tank 140 to the aerobic tank 120, it is possible to replenish some of the dissolved oxygen required for the nitrate microorganisms in the aerobic tank 120 to supply oxygen to the aerobic tank 120 The effect of reducing the blower operating power can be obtained.

As those skilled in the art would realize, the described embodiments may be modified in various ways, all without departing from the spirit or scope of the present invention. It is to be understood, however, that the present invention is not limited to the specific forms referred to in the description, but rather includes all modifications, equivalents, and substitutions within the spirit and scope of the invention as defined by the appended claims. Should be.

1 is a conceptual diagram schematically showing the configuration of the sewage and wastewater advanced treatment apparatus according to the present invention.

<Explanation of symbols for the main parts of the drawings>

110: first anaerobic tank 120: aerobic tank

130: second anoxic tank 140: membrane separation tank

150: separator 160: sludge denitrification tank

170: first conveying line 180: second conveying line

Claims (2)

An advanced biological treatment device comprising an immersion separator, A first anoxic tank 110 for denitrifying the nitrate nitrogen in the sewage and wastewater; An aerobic tank 120 connected to the first anoxic tank 110 to perform organic material oxidation and nitrification; A second anoxic tank 130 connected to the aerobic tank 120 for further denitrification of nitrate nitrogen; A membrane separation aeration tank 140 connected to the second anoxic tank 130 to oxidize residual organic matter, nitrification occurs, and solid-liquid separation between the treated water and microorganisms; A separation membrane 150 installed in the membrane separation tank 140 to separate treated water and sludge; A sludge denitrification tank 160 connected to the first anoxic tank 110 to remove some nitrate nitrogen and residual dissolved oxygen; A first conveying line 170 conveying activated sludge in the exhalation tank 120 to the sludge denitrification tank 160; And And a second conveying line (180) for conveying the activated sludge in the membrane separation tank (140) to the aerobic tank (120). The method of claim 1, Said waste water, Sewage denitrification tank 160 and the first anoxic tank 110, characterized in that configured to be introduced to flow into the sewage, wastewater advanced treatment apparatus.

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