KR20070072980A - Waste water treatment apparatus using high concentrated organic compound comprising waste water and waste water treatment method using the apparatus - Google Patents

Abstract

An apparatus for treating wastewater by using high concentrated organic compound-containing wastewater as a carbon source instead of methanol as a nutrition source of denitrifying microorganisms, and returning sludge recovered from a settling tank to an anoxic tank to recover the denitrifying microorganisms, and a method for treating wastewater using the apparatus are provided. In a wastewater treatment apparatus comprising an anoxic tank, an aerobic tank connected to the anoxic tank, and a settling tank connected to the aerobic tank, a wastewater treatment apparatus using high concentrated organic compound-containing wastewater comprises: a first raw water line for supplying first raw water that is wastewater containing nitrate-nitrogen to be removed, and a second raw water line for supplying second raw water that is high concentrated organic compound-containing wastewater, wherein the first and second raw water lines are connected to the anoxic tank; and a return line for returning a portion of sludge discharged from the settling tank to the anoxic tank.

Description

Waste water treatment apparatus using high concentrated organic compound comprising waste water and waste water treatment method using the apparatus}

Figure 1 is a schematic diagram showing the configuration of a wastewater treatment apparatus using a high concentration organic wastewater in accordance with the present invention.

Figure 2 is a graph showing the analysis results for the chemical oxygen demand during the operation period by the wastewater treatment method using a wastewater treatment apparatus using a high concentration organic wastewater according to the present invention.

Figure 3 is a graph showing the analysis results for the nitrate nitrogen during the operation period by the wastewater treatment method using a wastewater treatment apparatus using a high concentration organic wastewater according to the present invention.

Figure 4 is a graph showing the analysis results for the total nitrogen during the operation period by the wastewater treatment method using a wastewater treatment apparatus using a high concentration organic wastewater according to the present invention.

The present invention relates to a wastewater treatment apparatus using a high concentration organic wastewater and a wastewater treatment method using the same, in particular, in the biological treatment of wastewater containing nitrate nitrogen, a high concentration organic matter instead of methanol as a nutrient source of denitrification microorganisms involved in the denitrification reaction A wastewater treatment apparatus using a high concentration organic wastewater, and a wastewater treatment method using the same, characterized in that the wastewater is used as a carbon source and the sludge recovered from the settling tank is returned to the anoxic tank for recovery of the denitrification microorganism.

In the semiconductor industry or the electronics industry, which is a high-tech industry, wastewater containing a high concentration of nitrate nitrogen is generated by operating a pickling process using nitric acid.

In order to remove nitrogen biologically, a two-step reaction is basically required. The first step is nitrification, which oxidizes ammonia nitrogen to nitrate nitrogen. The second step is denitrification, which converts nitrate nitrogen into nitrogen gas and releases it into the atmosphere. Therefore, the removal of nitrogen in water means that the denitrification reaction is completed and finally converted to nitrogen gas state, which means that the nitrification can be carried out before the denitrification reaction, which is a subsequent reaction.

The main microorganisms involved in nitrification are nitrosomonas nitrobacter. They are classified as autotrophic bacteria because the energy required for growth is obtained by the oxidation of inorganic nitrogen. Nitrozomonas oxidizes ammonia nitrogen to nitrites, and nitrobacter oxidizes the nitrites produced by nitrozomonas to nitrates. Therefore, in order to complete nitrification, two successive reactions must be carried out, and the water treatment process must satisfy the appropriate environmental conditions for the symbiosis of nitrozomonas and nitrobacter.

Nitrification is the conversion of ammonia ion (NH ₄ ⁺ ) into nitrate ion (NO ₃ ⁻ ) by two steps by autotrophic bacteria.

The overall reaction of nitrification is shown in Scheme 1 below.

Stage 1 ; _{2NH 3 + 3O 2 → 2NO 2} - + 2H + + 2H 2 O ( nitro crude Pseudomonas)

2 step; ^{_{2NO 2 - + O 2 → 2NO}} 3 - ( nitro bakteo)

Total reaction (1); _{2NH 3 + 4O 2 → 2NO 3} - + 2H + + 2H 2 O

Dividing both sides of the overall reaction (1) by 2 can be represented by the following scheme 2.

Total reaction; _{NH 3 + 2O 2 → NO 3} - + H + + H 2 O

Adding hydrogen ions to both sides of Scheme 2 may be represented by the following Scheme 3.

Total reaction; ^{_{NH 4 + + 2O 2 → NO}} 3 - + 2H + + H 2 O

The main environmental factors in the nitrification reaction include pH, temperature and dissolved oxygen (DO). The optimum pH of the nitrification reaction is 7.5 to 8.6, and the reaction rate is maximized at the pH slightly higher than 8. In particular, since the alkalinity is consumed during the reaction, the pH tends to decrease. The temperature is proportional to the rate of nitrification, and the amount of dissolved oxygen requires 1 mg / l or more, and below that, oxygen acts as a limiting substrate. And high concentrations of inorganic nitrogen inhibit the growth and activity of nitrate bacteria.

The denitrification is to emit, to remove with a nitrogen gas (N ₂₎ by bacterial reduction of the nitric acid, the process in the nitrate ion (NO ₃ ^-), so is used as a hydrogen acceptor and in an oxygen-free reaction, the injection of methanol as a carbon source In this case, the entire reaction is shown in Scheme 4 below.

Stage 1 ; ^{_{6NO 3 - + 2CH 3 OH →}} 6NO 2 - + 2CO 2 + 4H 2 O

2 step; ^{_{6NO 2 - + 3CH 3 OH →}} 3N 2 + 3CO 2 + 3H 2 O + 6OH -

Total reaction; ^{_{6NO 3 - + 5CH 3 OH →}} 5CO 2 + 3N 2 + 7H 2 O + 6OH -

Cell synthesis reaction; ^{_{3NO 3 - + 14CH 3 OH +}} CO 2 + 3H + → 3C 5 H 7 O 2 N + 19H 2 O

The main environmental factor in the denitrification process is dissolved oxygen as a decisive factor and inhibits the enzyme system. Only when the dissolved oxygen amount is 1 mg / l or more, various kinds of nitrate reductases are inhibited and the denitrification rate is linearly reduced to almost zero.

In addition, the optimum pH is in the range of 7 to 8, the alkalinity is generated and the pH tends to increase.

Temperature affects nitrate removal and microbial growth in proportion to the reaction rate. The concentration of the substrate is also proportional to the denitrification rate, which requires an external carbon source for cell synthesis. Carbon sources include influent sewage, cell bodies (endogenous metabolism), and methanol. Representative advanced sewage treatment technologies for denitrification include intermittent aeration and separation membranes.

First, the process using the intermittent aeration method is operated by controlling the amount of dissolved oxygen in the aeration tank without changing the existing facilities in the treatment of nitrogen and phosphorus to reduce the aeration cost and effectively solve the sludge flotation caused by denitrification at the final sedimentation basin. Has the advantage.

A) STAR (Samsung Tetra A Reactor) process

It consists of a conveyance line that connects the entire oxygen tank-anaerobic tank-intermittent aeration tank-secondary sedimentation tank and secondary sedimentation tank. The intermittent aeration tank alternately creates anoxic and aerobic conditions using blowers and agitators under the control of Oxidation Reduction Potential (ORP) / timers. The influent sewage flows into 80% of anoxic tanks and 20% of total anoxic tanks.

B) HDF (Hanhwa Dynamic Flow) process

Inflow water is introduced into the first and second reaction tanks alternately by changing the flow path, and each reactor is operated in an intermittent aeration method to increase the denitrification and dephosphorization efficiency. The reactor consists of sludge activation tank, anaerobic tank, first reactor, second reactor, third reactor, reaeration tank and precipitation tank.In the sludge activation tank, sludge reduction and endogenous denitrification by sludge self-oxidation occur. Adsorption decomposition and phosphorus release occur at the same time, acting as a selector. In the first reactor, the second reactor, and the third reactor, anoxic and aerobic states are operated alternately to cause nitrification, denitrification, and excessive ingestion of phosphorus.

C) DASpro (Daelim Advanced Sludge Reaeration Process for nutrient removal) process

As a method of efficiently maintaining the amount of microorganisms required for nitrification in the system, a method of reaeration of the return sludge is used. In the system, the aeration part is divided into two parts. One is the general aerobic tank, which removes organic matter and nitrifies, and the other is the sludge re-aeration tank, which aeration sludge. The return sludge concentration from the bottom of the sedimentation basin where MLSS (Mixed Liquor Suspended Solids) is precipitated and concentrated is generally about 8,000 to 10,000 mg / l, and the aeration is about 4,000 mg / l. It can be judged to have more than twice the effect than aeration of the general aerobic tank. In addition, the use of the sludge reaeration tank is similar to the aeration tank front end of a step aeration method, and even if a large amount of low inflow water flows into the system by storing a portion of the conveying sludge in the system. It has the ability to continuously feed mixed liquor from this without sludge washout. Anaerobic tank to induce phosphorus release, anoxic tank to remove nitrate nitrogen from reaeration tank, aerobic tank to remove organic matter and nitrification, and stable supply of sludge to the system while supplying nitrogen nitrate to anoxic tank It consists of sludge reaeration tank. The supply of mixed liquor floatation to the anaerobic tank is carried out from an anoxic tank that carries out nitrogen removal, which maintains the anaerobic tank in a complete anaerobic state with no nitrate and dissolved oxygen, the UCT method (University of Cape Town, South Africa). It is equivalent to supplying MLSS to anaerobic tanks in anaerobic, as in the process developed in) or the VIP process (similar to the UCT process).

D) Advanced sewage treatment using anaerobic / intermittent aeration / culture tanks (HBR-Ⅱ)

The bioreactor is composed of anaerobic / intermittent aeration / culture tanks to induce phosphorus release in the anaerobic tank, and the aeration / non-aeration cycle is applied in the intermittent aeration tank to induce nitrification and excess intake of aeration and denitrification during aeration. It is a sewage treatment technology to reduce the occurrence of odor by circulating the sludge under low oxygen, low load conditions to the anaerobic tank by removing the microorganism (Pellet / Stone) in the culture tank.

In addition, the advanced treatment method using the separation membrane is to separate the mixture by selectively passing a specific component through the separation membrane, the currently developed membrane separation techniques such as microfiltration, ultrafiltration, gas separation (gas separation) And electrodialysis, and the like, and separation principles such as pore size and adsorption, dissolution and diffusion at the membrane surface, and the like.

E) Advanced treatment system for sewage and wastewater using submerged flat membrane (ENVIS ^® SYSTEM)

The techniques of the size of the pore diameter of the flat membrane 0.4㎛ (flat sheet membrane) a plate-like submerged microfiltration membrane separation system to the existing biological treatment step, the standard activated sludge process, and advanced treatment process of the treatment of waste water by (A ² / O series, SBR series, etc.) to obtain a stable treated water as a supernatant through solid-liquid separation of contaminants and active microorganisms in the aeration tank except ionic and colloidal substances. By introducing air scrubbing from the bottom of the module without backwashing, it is possible to control the fouling during operation. This flat membrane module is intermittent suction filtration by the out-in cross flow filtration method, and the operation suction pressure is 0 to 0.5kg _f / ㎠ or less (operating standard: 0.2kg _f / ㎠) At a low pressure of, the flux per membrane module is operated at 0.30 to 0.38 m 3 / m 2 · day.

F) HS-aMBR (Sewage treatment using ultrafiltration hollow fiber membrane)

This technology removes organic matter, nitrogen and phosphorus by MBR (Membrane Bio-Reactor) sewage treatment process consisting of anaerobic tank, stabilization tank, anoxic tank, and membrane separation tank, and UF (ultra filtration) hollow fiber membrane is immersed in the tank. It is a technology to reduce suspended solids (SS) and coliform group, and to concentrate the drawn excess sludge at high concentration through UF (ultrafiltration) membrane in membrane separation tank under aerobic conditions.

However, in order to complete the denitrification, any of the conventional sewage treatment methods and facilities described above must be supplied with a carbon source as a nutrient source of microorganisms necessary for denitrification, or use a filtration membrane or the like. There is a disadvantage that requires a lot of effort and effort. Moreover, methanol is mainly used as a carbon source, and in order to use methanol as a carbon source, space is required due to installation of a tank for storing methanol in a sewage treatment facility, and methanol is a combustible material and is specially managed as a dangerous material for fire fighting. There should be a problem.

On the other hand, high concentration organic wastewater containing high concentrations of organic substances such as polyethylene glycol is also generated in the semiconductor industry or the electronics industry, which also has to be treated as industrial waste, which takes a lot of time and effort. There is a problem.

The present invention uses a high concentration organic wastewater as a carbon source instead of methanol as a nutrient source for denitrification microorganisms involved in the denitrification in biological treatment of wastewater containing nitrate nitrogen, and sludge recovered in a sedimentation tank for recovery of the denitrification microorganism. It is an object of the present invention to provide a wastewater treatment apparatus using a high concentration organic wastewater and a wastewater treatment method using the same, characterized in that it is made to return to an anoxic tank.

A wastewater treatment apparatus using a high concentration organic wastewater for achieving the object of the present invention as described above, in the wastewater treatment apparatus comprising an oxygen-free tank, an aerobic tank connected to the anoxic tank and a precipitation tank connected to the aerobic tank, the first The first raw water line for supplying the wastewater containing nitrate nitrogen to be treated as raw water and the second raw water line for supplying the high concentration organic wastewater as the second raw water are connected to the anoxic tank and the sludge discharged from the settling tank Characterized in that a conveying line for conveying a part to the anoxic tank is provided.

In addition, the wastewater treatment method using a high concentration organic matter wastewater for achieving the object of the present invention, including an anoxic tank, an aerobic tank connected to the anoxic tank and a sedimentation tank connected to the aerobic tank containing nitrogen nitrate. In the wastewater treatment to remove the nitrate nitrogen by the denitrification reaction by the microorganisms, (1) a raw water inflow step of introducing a wastewater and high concentration organic wastewater containing nitrogen nitrate to be treated into the anoxic tank; (2) an anoxic reaction step of converting nitrate nitrogen to nitrogen gas by denitrification microorganisms contained in the sludge for 8 to 10 hours while maintaining the dissolved oxygen level in the anoxic tank; (3) a first transfer step of transferring a portion of the anoxic reaction treated liquid mixture to the aerobic tank; (4) an aerobic reaction step for continuously aeration of the mixed liquid introduced into the aerobic tank to remove residual organic matter and nitrification (5) a second transfer step of transferring a part of the mixed liquid which has undergone the aerobic reaction step from the aerobic tank to the settling tank; (6) settling the mixed liquid introduced into the settling tank to precipitate the suspended matter, and then discharging the supernatant and separating the precipitated sludge; And (7) a part of the sewage collected sludge is returned to the anoxic tank, and the third sludge is disposed of for disposal.

In the raw water inflow step, wastewater containing nitrate nitrogen and high concentration organic matter wastewater may be adjusted to be introduced at a ratio of 1: 2.5 to 3.5 by weight.

In the raw water inflow step, the concentration of wastewater containing nitrate nitrogen may be adjusted to 350 to 450 mg / L.

The concentration of the high concentration organic wastewater in the raw water inflow step may be adjusted to 1,100 to 1,200mg / l on the basis that the concentration of the wastewater containing nitrate nitrogen is within the range of 350 to 450mg / l.

The organic material included in the high concentration organic matter wastewater in the raw water inflow step may be preferably polyethylene glycol.

Denitrification microorganism in the anoxic reaction step may be preferably Pseudomonas (Pseudomonas).

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Wastewater treatment apparatus using a high concentration organic matter wastewater according to the present invention, as shown in Figure 1, in the wastewater treatment apparatus comprising an anaerobic tank, an aerobic tank connected to the anoxic tank and a sedimentation tank connected to the aerobic tank, the first raw water A first raw water line for supplying wastewater containing nitrogen nitrate to be treated as a second source and a second raw water line for supplying high concentration organic wastewater as a second raw water are connected to the anoxic tank and part of the sludge discharged from the settling tank. Characterized in that it is provided with a conveying line for conveying to the anoxic tank. That is, in the present invention, in the denitrification by converting nitrate nitrogen to nitrogen gas in an anoxic tank using denitrification microorganisms, instead of using conventional methanol as a carbon source as a nutrient source for denitrification microorganisms, high concentration organic wastewater also requires wastewater treatment. It is characterized in that the denitrification by using as a carbon source to treat the wastewater containing nitrate nitrogen and the high concentration organic wastewater together. The anoxic tank is connected to the first raw water line and the second raw water line, through which the wastewater containing nitrate nitrogen is introduced through the first raw water line, and the high concentration organic wastewater through the second raw water line, respectively. In the anoxic tank, the nitric oxide is converted to nitrogen gas by an anoxic reaction by denitrification microorganisms contained in the sludge, and the nitrogen gas is released into the atmosphere to be denitrated. In addition, the sludge in which the denitrification microorganisms are present is recovered from the settling tank so that a part of the denitrification microorganism can be returned to the anoxic tank and used repeatedly so that continuous wastewater treatment can be performed without separately inoculating the denitrification microorganism.

In addition, the wastewater treatment method using a high concentration organic matter wastewater for achieving the object of the present invention, including an anoxic tank, an aerobic tank connected to the anoxic tank and a sedimentation tank connected to the aerobic tank containing nitrogen nitrate. In the wastewater treatment to remove the nitrate nitrogen by the denitrification reaction by the microorganisms, (1) a raw water inflow step of introducing a wastewater and high concentration organic wastewater containing nitrogen nitrate to be treated into the anoxic tank; (2) an anoxic reaction step of converting nitrate nitrogen into nitrogen gas by denitrification microorganisms contained in the sludge for 8 to 10 hours while maintaining the dissolved oxygen level in the oxygen-free tank; (3) a first transfer step of transferring a portion of the anoxic reaction treated liquid mixture to the aerobic tank; (4) an aerobic reaction step for continuously aeration of the mixed liquid introduced into the aerobic tank to remove residual organic matter and nitrification; (5) a second transfer step of transferring a portion of the mixed liquid passed through the aerobic reaction step to the settling tank; (6) settling the mixed liquid introduced into the settling tank to precipitate the suspended matter, and then discharging the supernatant and separating the precipitated sludge; And (7) a part of the settled sludge is returned to the anoxic tank, and the remaining sludge is disposed in a third transfer step for disposal.

In the raw water inflow step of (1), the denitrification included in the sludge in the subsequent anoxic reaction step is performed by allowing two or more raw waters, that is, wastewater containing nitrate nitrogen and high concentration organic matter wastewater, into the same tank, that is, an anaerobic tank. Denitrification by the microorganisms to convert the nitrate nitrogen to nitrogen gas, wherein the organic material contained in the high concentration organic matter wastewater introduced with the wastewater containing the nitrate nitrogen as a nutrient source of the denitrification microorganism as a carbon source Do it. Therefore, according to the present invention, wastewater treatment by denitrification and wastewater of high concentration organic matter wastewater are used as nutrient sources of denitrification microorganisms in wastewater containing nitrogen nitrate, so that wastewater treatment by treatment of organic matter in high concentration organic wastewater can be simultaneously performed. It is characteristic of one point.

The anoxic reaction step of (2) literally converts the nitrate nitrogen to nitrogen gas by the denitrification microorganism contained in the sludge for 8 to 10 hours while maintaining the oxygen free state so that the amount of dissolved oxygen is zero in the anoxic tank. It is made to make. When the anoxic reaction step is performed in less than 8 hours, there may be a problem that the denitrification efficiency is lowered because the nitrogen nitrate is not sufficiently converted to nitrogen gas, on the contrary, if more than 10 hours, the denitrification rate by the denitrification microorganism, that is, Nitrogen removal rate may be higher, but there may be a problem that the overall processing rate is lowered due to the slower processing speed.

The first transfer step of (3) transfers a portion of the anoxic-treated raw water from the oxygen-free tank to the aerobic tank so that a subsequent aeration step can be performed. At this time, the anoxic reaction raw water is preferably collected near the bottom of the anoxic tank.

The aerobic reaction step of (4) consists of an aerobic reaction for continuously aeration of the mixed liquid introduced into the aerobic tank to remove residual organic matter and nitrification. The residence time or aeration time in the aerobic reaction step may vary depending on the volume of the aerobic tank and the treatment volume of the entire system, and it will be understood by those skilled in the art that an appropriate aeration time can be determined according to the treatment volume.

The second transfer step of (5) consists of transferring a portion of the mixed liquid that has undergone the aerobic reaction step from the aerobic tank to the settling tank, transferring the mixed solution which has already been denitrated to the settling tank, and suspended matter in a subsequent settling step. Settle to remove sludge. This can be understood as to convey the suspended solids or sludge in the mixed liquid to remove and settle the suspended solids and sludge from the mixed liquid in the settling tank.

In the precipitation step (6), the mixed solution introduced into the settling tank is left to settle the suspended matter, and then the supernatant is discharged and the precipitated sludge is separated, and the sludge is separated and collected, and a part of the subsequent In the third transfer step, it is returned to the anoxic tank, and the remaining sludge is discarded, and in this step, one cycle of wastewater treatment is terminated, and the steps (1) to (7) are repeatedly and continuously as necessary. Proceed to enable wastewater treatment.

In the raw water inflow step, wastewater containing nitrate nitrogen and high concentration organic matter wastewater may be adjusted to be introduced at a ratio of 1: 2.5 to 3.5 by weight. When the high concentration organic wastewater flows in less than 2.5 on the basis of the wastewater containing nitrate nitrogen, the organic matter content is relatively low so that the denitrification microorganisms do not fully grow and the efficiency of the denitrification reaction is lowered, thereby reducing the nitrogen content. There may be a problem that can not be sufficiently removed, on the contrary, if it exceeds 3.5, there may be a problem that the chemical oxygen demand is increased by the high concentration of organic wastewater used in the denitrification reaction.

In the raw water inflow step, the concentration of wastewater containing nitrate nitrogen may be adjusted to 350 to 450 mg / L. The concentration range of the wastewater containing nitrate nitrogen is a standard of the wastewater treatment, in particular, the determination of the concentration of the high concentration organic wastewater and the amount of its use for the treatment of the wastewater containing the nitrate nitrogen.

The concentration of the high concentration organic wastewater in the raw water inflow step may be adjusted to 1,100 to 1,200mg / l on the basis that the concentration of the wastewater containing nitrate nitrogen is within the range of 350 to 450mg / l. When the concentration of the high concentration organic wastewater is less than 1,100 mg / L, the organic matter content is relatively too low, the denitrification microorganisms are not sufficiently grown, the efficiency of the denitrification reaction may be reduced, thereby not enough to remove the nitrogen component On the contrary, if it exceeds 1,200 mg / L, there may be a problem that the chemical oxygen demand of the treated water obtained after the treatment due to organic matter remains.

The organic material included in the high concentration organic matter wastewater in the raw water inflow step may be preferably polyethylene glycol.

Hereinafter, preferred embodiments and comparative examples of the present invention will be described.

The following examples are intended to illustrate the invention and should not be understood as limiting the scope of the invention.

Example  One

The capacity of the anaerobic tank, the aerobic tank, and the settling tank of the pilot plant was 24 L (oxygen tank), 5 L (aerobic tank), and 9 L (precipitation tank), respectively. The concentration of influent water was about 400 mg / l using nitric acid (KNO ₃ ) as wastewater containing nitrate nitrogen, and experiments using polyethylene glycol as a high concentration organic wastewater as an external carbon source of anoxic tank It was. The inflow of the high concentration organic wastewater was injected at a concentration of 1,200 mg / l. At the beginning of the experiment, denitrification microorganisms were cultured using raw water as wastewater generated in electronic and semiconductor processes (temperature: 25 ° C., supplemented with denitrification bacteria), and the operating conditions are shown in Table 1 below. The denitrification supplement was obtained by collecting samples from the sewage treatment plant aeration tank under initial culture conditions, separating the denitrifying bacteria (Pseudomonas) by dilution, performing plate culture for 2 to 3 days, and then forming the colonies again in Giltay medium. After inoculation to confirm that it is a denitrifying bacterium, the strain was separated and stored by subcultured on a plate count agar medium. Since denitrifying bacteria are organic nutrients, they can be cultured easily because of their rapid cultivation. The cells were initially replenished in an amount of 0.1% of the anaerobic tank, that is, 20 ml.

Item Operating conditions Hydraulic stay time (hours) Anaerobic 10 Aerobic 2.1 Volume (ℓ) Anaerobic 24.0 Aerobic 5.0 Flow rate (ℓ / hour) enemy 2.4 Bounce sludge 3.0 Mixed liquid suspended solids (mg / l) Anaerobic 2,200 to 2,500 Aerobic 2,200 to 2,400

Experimental Example  One

Wastewater treatment was carried out under the conditions of Example 1, and the experimental results of the chemical oxygen demand (COD _Mn ) are shown graphically in FIG. 2. As shown in FIG. 2, in the case of using a high concentration organic wastewater containing polyethylene glycol as a carbon source according to the present invention, the inflow average concentration of chemical oxygen demand was 1,215.60 mg / l, the minimum value was 1,130 mg / l, and the maximum value was 1,340 mg / l. The chemical oxygen demand of the treated water after the denitrification process was 120.71mg / l on average, and the minimum and maximum values were 75.3mg / l and 308.75mg / l, respectively, and the treatment rate was 90.12% on average. 73.8% and 95.3%, respectively. Table 2 below summarizes the analysis results for the chemical oxygen demand during the operation of Example 1.

Item Raw water (mg / ℓ) Supernatant (mg / ℓ) % Removal Average 1,215.60 120.71 90.1 Minimum value 1,130 75.3 73.8 Value 1,340 308.75 95.3

Experimental Example  2

Wastewater treatment was performed under the conditions of Example 1, and the experimental results of the nitric acid nitrate are shown in a graph in FIG. As shown in FIG. 3, in the case of using a high concentration organic wastewater containing polyethylene glycol as a carbon source according to the present invention, the inflow average concentration of nitrate nitrogen was 424.4 mg / l, the minimum value was 360 mg / l, and the maximum value was 520 Mg / l. The concentration of nitrate nitrogen in the treated water after denitrification was 41.5 mg / l on average, and the maximum and maximum values were 20 mg / l and 78 mg / l, respectively. The treatment rate was 90.0% on average. Were 81.0% and 95.0%, respectively. Table 3 below summarizes the analysis results for the nitric acid nitrate during the operation of Example 1.

Item Raw water (mg / ℓ) Supernatant (mg / ℓ) % Removal Average 424.4 41.5 90.0 Minimum value 360 20 81.0 Value 520 78 95.0

Experimental Example  3

Wastewater treatment was performed under the conditions of Example 1, and the experimental results of total nitrogen are shown in a graph in FIG. As shown in Figure 4, in the case of using a high concentration organic wastewater containing polyethylene glycol as a carbon source according to the present invention, the total nitrogen inflow average concentration was 491.1 mg / ℓ, the minimum value is 402 mg / ℓ, the maximum value is 599 Mg / l. The concentration of nitrate nitrogen in the treated water after denitrification was 51.7 mg / l on average, and the maximum and maximum values were 30 mg / l and 97 mg / l, respectively, and the treatment rate was 89.2% on average. Were 77.8% and 93.4%, respectively. Table 4 summarizes the analysis results for the total nitrogen during the operation of Example 1.

Item Raw water (mg / ℓ) Supernatant (mg / L) % Removal Average 491.1 51.7 89.2 Minimum value 402 30 77.8 Value 599 97 93.4

As a result of the synthesis of the above embodiments, the wastewater containing the nitrogenous nitrate with a total nitrogen inflow average concentration of 491.1 mg / l was used as the carbon source as the organic wastewater with the inflow average concentration of the chemical oxygen demand of 1,215.60 mg / l as the carbon source. Is as follows.

1) The mean concentration of chemical oxygen demand was 1,215.60 mg / l, and the average concentration of treated water was 120.71 mg / l, indicating a 90.1% treatment efficiency. Therefore, it was found that it was used as a carbon source for denitrification.

2) The mean concentration of nitrate nitrogen was 424.4 mg / l, and the average concentration of treated water was 41.5 mg / l, which showed a high treatment efficiency of about 90.0%.

3) The mean concentration of total nitrogen was 491.1 mg / l and the average concentration of treated water was 51.7 mg / l, which showed a high nitrogen removal efficiency of 89.2%.

As described above, the present invention uses a high concentration of organic wastewater as a carbon source instead of methanol as a nutrient source for denitrification microorganisms involved in denitrification in biological treatment of wastewater containing nitrate nitrogen, and for recovering the denitrification microorganism. It is effective to provide a wastewater treatment apparatus using a high concentration organic wastewater and a wastewater treatment method using the same, characterized in that the sludge recovered in the settling tank is returned to an anoxic tank.

Claims (6)

In the waste water treatment apparatus comprising an anoxic tank, an aerobic tank connected to the anoxic tank and a precipitation tank connected to the aerobic tank, A first raw water line for supplying wastewater containing nitrate nitrogen to be treated as a first raw water and a second raw water line for supplying high concentration organic wastewater as a second raw water are connected to the anoxic tank and discharged from the settling tank. Waste water treatment apparatus using a high concentration organic waste material, characterized in that the conveying line for conveying a portion of the sludge to the anoxic tank is provided. A wastewater treatment system comprising an anoxic tank, an aerobic tank connected to the anoxic tank, and a sedimentation tank connected to the aerobic tank is used for wastewater treatment to remove nitrate nitrogen by denitrification by microorganisms. In (1) a raw water inflow step of introducing wastewater and high concentration organic matter wastewater containing nitrate nitrogen to be treated into the anoxic tank; (2) an anoxic reaction step of converting nitrate nitrogen to nitrogen gas by denitrification microorganisms contained in the sludge for 8 to 10 hours while maintaining the dissolved oxygen level in the anoxic tank; (3) a first transfer step of transferring a portion of the anoxic reaction treated liquid mixture to the aerobic tank; (4) an aerobic reaction step for continuously aeration of the mixed liquid introduced into the aerobic tank to remove residual organic matter and nitrification; (5) a second transfer step of transferring a portion of the mixed liquid passed through the aerobic reaction step to the settling tank; (6) settling the mixed liquid introduced into the settling tank to precipitate the suspended matter, and then discharging the supernatant and separating the precipitated sludge; And (7) a third conveyance step of returning a portion of the sewage sludge collected to the anoxic tank and discarding the remaining sludge; Wastewater treatment method using a high concentration organic wastewater, characterized in that made. The method of claim 2, Wastewater treatment method using a high concentration of organic wastewater, characterized in that the raw water inflow step is controlled to flow in a ratio of 1: 2.5 to 3.5 in the waste water and the high concentration organic wastewater containing nitrate nitrogen. The method of claim 2, Wastewater treatment method using a high concentration organic wastewater, characterized in that the concentration of wastewater containing nitrate nitrogen in the raw water inflow step is adjusted to 350 to 450mg / l. The method of claim 2, The concentration of the high concentration organic wastewater in the raw water inflow step is adjusted to 1,100 to 1,200 mg / L on the basis that the concentration of the wastewater containing nitrate nitrogen is within the range of 350 to 450 mg / L. Wastewater treatment method using organic wastewater. The method of claim 2, Wastewater treatment method using a high concentration organic wastewater, characterized in that the organic material contained in the high concentration organic wastewater in the raw water inflow step.

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