JPH09290289A - Device for biologically removing nitrogen and phosphorus in sewage and method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device and a method thereof for biologically removing nitrogen and phosphorus in which microorganisms in sludge is prevented from flowing out even when sewage to be treated has low concentration and low temperature and also phosphorus is removed with high efficiency.

SOLUTION: This device is constituted of a treating tank 1 in which anaerobic tanks for dephosphorization 1-2, 1-3, oxygen free tanks for denitrification 1-4, 1-5 and aeration tanks for nitrification 1-6, 1-7, 1-8, 1-9 are installed and connected interlocked with each other in order, a final sedimentation basin 2 interlocked with the last stage aeration tank 1-9, an inflow water route 3 installed between a first sedimentation basin and the poststage anaerobic tank 1-3, an inner circulating route 4 installed between the last stage aeration tank 1-9 and the prestage oxygen free tank 1-4 for denitrifying nitrifying nitrogen, and a sludge returning route 5 installed between the final sedimentation basin 2 and the prestage anaerobic tank 1-2 to biologically remove nitrogen and phosphorus in sewage.

COPYRIGHT: (C)1997,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a treatment method for efficiently removing BOD components, nitrogen components and phosphorus components contained in sewage with microorganisms.

[0002]

In the conventional sewage treatment method, in the case of low-concentration or low-temperature sewage, the removal rate of the organic substances is insufficient because the conditions for the microorganisms to decompose the organic substances are insufficient. There was a problem that it was low. In addition, sludge was washed away from the anaerobic tank, making it difficult to remove nitrogen and phosphorus.

The present invention has been devised in order to overcome such problems, and the problem to be solved by the present invention is that sludge is generated in the anaerobic tank even in the case of low concentration and low temperature sewage. Nitrogen and phosphorus in the sewage are continuously supplied to prevent the loss of microorganisms in the sludge, and because the anaerobic tank in the previous stage has a sludge storage function, the decomposition reaction of phosphorus is activated to increase the dephosphorization efficiency. To provide a processing system.

[0004]

In order to solve the above problems, the present invention according to claim 1 introduces sewage from a primary settling tank to an anaerobic tank for dephosphorization, and then to an oxygen-free tank for dephosphorization. In order to biologically remove nitrogen and phosphorus in the sewage by conducting nitrification and then guiding it to an aeration tank, it is necessary to sequentially link multiple anaerobic tanks, multiple anoxic tanks and multiple aeration tanks. A treatment tank constructed by combining the above with a final settling tank which is linked to the above-mentioned last stage aeration tank through a connecting flow path and a discharge flow path is connected, and sewage discharged from the primary settling tank An influent system channel between the next settling basin and the rear anaerobic tank, an internal circulation channel between the last aeration tank and the front anoxic tank to denitrify nitrifying nitrogen, and the microorganisms in the treatment tank. In order to stably supply the The nitrogen and phosphorus in the sewage, characterized by being configured by the return pathway to provide a processing apparatus for biochemical removed.

The present invention according to claim 2 reduces the concentration of nitric acid in sludge, which is an inhibiting factor of the dephosphorization reaction, by introducing sludge from the final settling tank to the preceding anaerobic tank through the sludge return system. And prevent sludge from flowing away,
In the process of stably supplying the sludge necessary for dephosphorization, and in the second anaerobic tank, the sludge from the first anaerobic tank and the sewage discharged from the primary sedimentation tank are received, and the microorganisms in the anaerobic tank are desorbed while ingesting organic matter. Performing a phosphorus (PO4-3 -P release) reaction to dephosphorize and reduce BOD, and in an anoxic tank, nitric acid (NO
The process of receiving sewage containing 3--N) through an internal circulation system for denitrification, and in the aeration tank, the phosphorus component (PO4-3-P) released from the anaerobic tank is absorbed into the cells of the microorganism. Together with the step of nitrifying NH4 + -N in the sewage,
Provided is a treatment method for biologically removing organic matter, nitrogen and phosphorus in sewage.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail with reference to the drawings. FIG. 1 is a flow explanatory diagram showing an embodiment of a processing method according to the present invention. Reference numeral 1 indicates a processing tank. The treatment tank (1) includes two front and rear anaerobic tanks (1-2, 1-3),
Two front and rear oxygen-free tanks (1-4, 1-5) and four aeration tanks (1-6, 1-7, 1-8, 1-9) are arranged in this order. In addition to the above treatment tank (1), a final settling basin (2) is installed.

On the other hand, primary sedimentation pond (not shown in the drawing)
An inflow system (3) for supplying inflow is installed between the rear anaerobic tank (1-3) and the rear anaerobic tank (1-3).
An internal circulation path (4) for denitrifying nitrifying nitrogen is installed between the first stage anoxic tank (1-4) and the anoxic tank (1-2). A sludge return line (5) for returning sludge will be installed in between. Excess sludge is discharged from the final settling basin (2). Reference numeral 6 is a blower (BLOWE
R) is shown.

Hereinafter, the operation of the present invention by the processing apparatus having the above configuration will be described. The sewage with a small amount of organic matter and suspended solids removed from the primary sedimentation pond is the inflow system (3)
Is introduced into the latter stage anaerobic tank (1-3) through. On the other hand, sludge is returned from the final settling basin (2) to the above-mentioned anaerobic tank (1-2) through the sludge returning system path (5), and it is necessary for the dephosphorization reaction performed in the following anaerobic tank (1-3). The sludge can be stably supplied. Then, by passing the returned sludge through the former anaerobic tank (1-2), it is possible to reduce the concentration of nitrifying nitrogen contained in the returned sludge, which interferes with the dephosphorization reaction, and to minimize its effect. . Therefore, the reaction conditions necessary for the dephosphorization reaction are formed in the former anaerobic tank (1-2), and in the latter anaerobic tank (1-3), the organic matter existing in the sewage flowing from the inflow water system channel (3) is removed. The phosphorus reaction is effectively carried out using microorganisms.

In the two-stage oxygen-free tank (1-4, 1-5),
Nitrifying nitrogen internally circulated to the anoxic tank (1-4) by the internal circulation system (4) installed between the anoxic tank (1-4) and the aeration tank (1-9). Microorganisms denitrify the mixed solution. Then, the ammonia nitrogen contained in the inflow water passes through the anaerobic tank (1-2, 1-3) and the anoxic tank (1-4, 1-5) and then the aeration tank (1-6, 1-).
7, 1-8, 1-9) and nitrified by the dissolved oxygen supplied by the blower (6),
The residual organic matter that has flowed into the aeration tank from the denitrification anoxic tank is oxidized. Further, the front and rear anaerobic tanks (1-
The phosphorus components dephosphorized in 2, 1-3), that is, the phosphorus components discharged to the outside of the microorganisms in these anaerobic tanks, pass through the anoxic tanks (1-4, 1-5) and are aeration tanks. (1
-6, 1-7, 1-8, 1-9), where it is absorbed into the cells of the microorganism. The final settling pond (2) above
The sludge settled in (1) is returned to the preceding anaerobic tank (1-2) through the return system path (5), and the supernatant water of the settling basin (2) is discharged to the outside.

[0010]

EFFECTS OF THE INVENTION According to the present invention having the above-mentioned constitution and action, for example, when the temperature is low in winter, the flow-off phenomenon of microorganisms during the dephosphorization reaction in the anaerobic tank can be prevented, and inflow water (primary precipitation) can be prevented. The reaction conditions necessary for the dephosphorization reaction can be stably formed in the former anaerobic tank by causing the effluent of the tank) to flow into the latter anaerobic tank.

[Brief description of drawings]

FIG. 1 is a flow explanatory diagram showing an example of an embodiment of the present invention.

[Explanation of symbols]

1 ... Treatment tank, 2 ... Final settling tank, 3 ... Influent water channel,
4 ・ ・ Internal circulation line, 5 ・ ・ Sludge return line, 1-2 ・ ・
(First stage) Anaerobic tank, 1-3 ... (Second stage) Anaerobic tank, 1-4.
・ (Front stage) anoxic tank, 1-5 ・ ・ Oxygen-free tank, 1-6, 1
-7, 1-8, ... Aeration tank, 1-9 .. (Last stage) aeration tank

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Lee Lee Shin, Republic of Korea Gyeonggi-do, Gwangmyeong-si, 600, Wanggye-dong, Hakkyo Apartment 102-1408 (72) Inventor Chang Yun Suk, Republic of Korea Gyeonggi-do, Suwon City, Chang'an District, Tingko Dong Dong New Apartment 202-904 (72) Inventor Pak Myung Kyun South Korea Gyeonggi-do, Suwon City, Chang'an Area, Tingko Dong Dong New Apartment 110-205 (72) Inventor Fo Leong Rock Republic of Korea Seoul City, Gwangjin District, Gukjeon 2-dong 60-13

Claims (2)

[Claims] 1. Nitrogen and phosphorus in sewage are introduced by introducing sewage from a primary precipitation tank to an anaerobic tank for dephosphorization, then introducing it to an oxygen-free tank for denitrification, and then introducing it to an aeration tank for nitrification. When biologically removing
2, 1-3), a plurality of oxygen-free tanks (1-4, 1-5) and a plurality of aeration tanks (1-6, 1-7, 1-8, 1-9) are connected so as to be linked in order. The final settling basin (2) in which the treatment tank (1) configured as described above and the last-stage aeration tank (1-9) are interlocked with each other through a connection channel and an exhaust channel is connected.
In order to denitrify the nitrifying nitrogen, an inflow water channel (3) provided between the primary sedimentation tank and the rear anaerobic tank (1-3) for inflowing the sewage discharged from the primary sedimentation tank. In order to stably supply microorganisms to the internal circulation system passage (4) provided between the last-stage aeration tank (1-9) and the front-stage anoxic tank (1-4), and the treatment tank (1). And nitrogen and phosphorus in the sewage biochemically, characterized by being constituted by the sludge return system passage (5) provided between the final settling basin (2) and the former anaerobic tank (1-2). The processing device to remove. 2. The concentration of nitric acid in the sludge, which is an inhibitory factor for the dephosphorization reaction, by introducing sludge from the final settling basin (2) into the upstream anaerobic tank (1-2) through the sludge return line (5). And a stable supply of the sludge necessary for dephosphorization while preventing the sludge from being washed away, and the sludge from the preceding anaerobic tank (1-2) in the latter anaerobic tank (1-3). The sewage discharged from the primary sedimentation pond is received, and the microorganisms in the anaerobic tank take in organic matter and dephosphorize (PO4-3 -P
Release) to perform dephosphorization and BO
In the step of reducing D and in the anoxic tank (1-4, 1-5), sewage containing nitric acid (NO3--N) nitrified in the aeration tank (1-6 to 1-9) is internally A step of receiving and denitrifying through the circulation path (4), and the aeration tank (1-6 to
1-9), the phosphorus component (PO4-3-P) released from the anaerobic tank (1-2, 1-3) is absorbed into the cells of the microorganism, and the NH4 + -N in the sewage is nitrified. A method for biologically removing organic matter, nitrogen and phosphorus in sewage, which comprises a step.