KR20000063330A - The sequencing combination of oxic, deaerobic, anaerobic and anoxic vessels for effective denitrification and dephosphorus in waste water - Google Patents

Abstract

PURPOSE: A four combination using aerobic, anaerobic and anoxic tank is provided, which is characterized in that nitrogen, phosphorous are removed efficiently. CONSTITUTION: In case of low concentrated wastewater, ODA2 process that is consisted of aerobic/deaerobic/anaerobic/anoxic reactor in order is adapted for wastewater treatment, and in case of high concentrated wastewater, AODA2 process that is consisted of anaerobic/aerobic/deaerobic/anaerobic/anoxic reactor is adapted. In addition, in case of wastewater with high organic content, AODA2O process that is consisted of anaerobic/aerobic/deaerobic/anaerobic/anoxic/aerobic reactor is used, in case of wastewater with low organic content, ODA2O process that is consisted of aerobic/deaerobic/anaerobic/anoxic/aerobic reactor is adapted.

Description

Sequencing combination of oxic, deaerobic, anaerobic and anoxic vessels for effective denitrification and dephosphorus in waste water}

Since high concentrations of manure, landfill leachate, and livestock wastewater contain large amounts of nitrate nitrogen and phosphorus phosphate, the problem of increasing the denitrification and dephosphorization efficiency during wastewater treatment is a focus of attention both at home and abroad. Because of the high nitrogen and phosphorus in the water, algae are generated in fresh water, causing eutrophication in reservoirs and lakes, threatening aquatic ecosystems such as freshwater fish, and causing enormous disruptions in the production of agricultural, industrial and tap water. In addition, salty seawater will create red tide, which will cause enormous damage to coastal fisheries. Therefore, the problem of increasing the efficiency of denitrification and dephosphorization in biological treatment of these wastewaters is very important. However, these wastewaters are treated by the existing A ² O process that is sequentially combined into the anaerobic, anaerobic and aerobic tanks currently used, but as shown in the following reaction, the ammonium ion ( ) Oxidation from nitric acid to nitric acid (NO ₃ ⁻ ) occurs in an aerobic tank where nitrate ions are reduced to nitrogen and oxygen in anaerobic and anaerobic tanks.

----------- Formula (1)

Equation (2)

Equations (1) and (2) are nitrous and nitrification reactions in aerobic tanks, respectively.

------------ Formula (3)

In the first stage of this reaction 1 mole of oxygen is released, in the second stage 3/2 moles of oxygen are released and in the final stage 1/2 mole of oxygen is released, resulting in 3 moles of oxygen in total. Therefore, the reaction of equation (3) is a reaction in which 2 moles of nitrate ions are decomposed to generate 3 moles of oxygen, so this reaction occurs in anaerobic and aerobic tanks. Therefore, in order to achieve an effective denitrification, the current A ² O process, as shown in Equations (1) and (2), is once reduced to nitrogen and oxygen in anaerobic and anaerobic tanks after ammonium ions are oxidized to nitrate in an aerobic tank. If the concentration of wastewater mentioned earlier is dilute, it must be converted to the OA ² process, which is a reverse A ² O process. Therefore, in order to achieve effective denitrification, the current A ² O process should be changed to OA ² process, which is a reverse A ² O process when the concentration of waste water is dilute. Although the present inventors have invented the application number 10-2000-0022095, there is a disadvantage that the anaerobic bacteria of the anaerobic tank are killed by not installing a degassing tank at the front of the anaerobic tank, so that the contents are improved and applied as follows. In the OA ² method, the aerobic tank is placed before the anaerobic tank, so the DO concentration in the aerobic tank wastewater is 2-3 ppm, so that the anaerobic bacteria are killed when the aerobic tank wastewater flows into the anaerobic tank. In order to prevent this phenomenon, a deaerobic vessel should be installed between the aerobic and anaerobic tanks to reduce the DO concentration in the wastewater to 0.2-0.3 ppm. In other words, the OA ² process, which is an aerobic, anaerobic, and anaerobic process, should be changed to the ODA ² process, which is an aerobic, degassing, anaerobic, and anaerobic process. And when the concentration of wastewater is high, high concentrations of organic matter must be decomposed beforehand, so it must be changed to the AODA ² method, which precedes the ODA ² method with anaerobic tank. And-in is absorbed and released from the anaerobic or anoxic tank in the aerobic tank, if the order to remove the acid property and the ammonium nitrogen that is dissolved in the waste water in the same time effectively the concentration of the waste dilute include ODA was added to the aerobic tank to the rear end ODA ² Method ² It is used for O method, and if the concentration of the waste water, the method AODA ² O connecting the aerobic tank to the rear end AODA ² method is the most suitable method.

However, in the conventional A ² O process, the aerobic tank for oxidizing ammonium ions to nitrate ions is not preceded by the anaerobic tank / anoxic tank, so that effective removal of nitrate nitrogen is theoretically impossible, and thus, ammonia nitrogen purification efficiency is greatly reduced.

Therefore, the present invention uses the ODA ² process consisting of an aerobic tank / degassing tank / anaerobic tank / anoxic tank when the concentration of wastewater is low in order to greatly improve the ammonia nitrogen removal efficiency of the so-called A ² O process composed of conventional anaerobic tank / anaerobic tank / aerobic tank. When the concentration of wastewater is high, an anaerobic tank / aerobic tank / degassing tank / anaerobic tank / anoxic tank (AODA ² ) method has been used to solve the technical problem of effectively removing ammonia nitrogen. In addition, in order to remove the ammonia nitrogen and phosphorus phosphorus dissolved in the waste water with high efficiency at the same time, when the concentration of organic matter in the waste water is dilute, an aerobic tank, degassing tank, anaerobic tank, anaerobic tank and aerobic tank (ODA ² O) method When the concentration of organic matter is high, the technical problem of using anaerobic tank, aerobic tank, degassing tank, anaerobic tank, anaerobic tank, and aerobic tank (AODA ² O) method was established. The theoretical basis has been described in detail in the technical field to which the aforementioned invention belongs, and in the prior art portion of the field.

1: Biological aerobic tank / degassing tank / anaerobic tank / anaerobic tank (ODA ² ) sequential wastewater treatment plan of the present invention.

Figure 2: biological anaerobic tank / aerobic tank / degassing tank / anaerobic tank / anaerobic tank (AODA ² ) sequential wastewater treatment plan of the present invention.

3: biological aerobic tank / degassing tank / anaerobic tank / anaerobic / aerobic tank (ODA ² O) sequential wastewater treatment plan of the present invention.

Figure 4: Biological anaerobic tank / aerobic tank / degassing tank / anaerobic tank / anaerobic / aerobic tank (AODA ² O) sequential wastewater treatment plan of the present invention.

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

(1) (17) (35) (53)-Wastewater Inlet

(2) (18) (36) (54)-First settler

(3) (19) (37) (55)-First settling sludge

(4) (21) (38) (42) (57) (61)-Aerobic tank

(5) (22) (39) (58)-Degassers

(6) (20) (23) (40) (56) (59)-anaerobic tank

(7) (24) (41) (60)-Anaerobic tank

(8) (25) (43) (62)-Final Settler

(9) (26) (44) (63)-Effluents

(10) (27) (45) (64)-final sedimentation sludge

(11) (28) (46) (65)-surplus sludge

(12) (29) (47) (66)-conveying sludge pipe

13, 14, 15, 16, 30, 31, 32, 33, 34, 48, 49, 50, 51, 52, 67, 68, 69 ) (70) (71) (72)-Mixed Fluid Circulation

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

FIG. 1 is a plan view of a biological aerobic / degassing tank / anaerobic tank / anoxic tank (ODA ² ) sequential wastewater treatment plan. Allow gravity to proceed with precipitation. At this time, the first settling sludge (3) to be settled separately. The wastewater after the first precipitation is introduced into the aerobic tank (4) to oxidize the ammonium ions to nitrate ions as shown in the reaction formula (1) and (2). The treated water of the aerobic tank 4 thus treated passes through the mixed liquid circulation path 13 and flows into the degassing tank 5. Here, the treated water treated under the degassing condition is introduced into the anaerobic tank 6 through the mixed liquid circulation passage 14. At this time, in the anaerobic tank 6 and the anoxic tank 7, the nitrate ions are reduced to nitrogen and oxygen and decomposed as in the reaction of the formula (3). The treated water of the anoxic tank 7 is transferred to the final settler 8 to coagulate or to separate the sludge using a filter. At this time, a part of the final sedimentation sludge 10 is returned to the aerobic tank 4 through the sludge conveying tube 12 to supplement the insufficient feed of activated sludge, and the remaining excess sludge 11 is squeezed with a belt press to be treated as a cake.

FIG. 2 is a plan view of a biological anaerobic tank / aerobic tank / degassing tank / anaerobic tank / anoxic tank (AODA ² ) sequential wastewater treatment. The function of the first settling sludge (19) of the inlet (17) and the first settling sludge (19) is shown in FIG. ) Same as the function in (3). When the concentration of organic matter in the waste water is high, the anaerobic tank 20 digests the organic matter under anaerobic conditions and then transfers it to the aerobic tank 21 through the mixed liquid circulation path 30. This reduces the load on the exhalation tank 21. 2 added an anaerobic tank 20 to the front of FIG. 1 for this purpose. In addition, the mixed liquid circulation paths 32 and 33 have the same functions as those of Figs. 14 and 15, respectively. Next, the role of the anaerobic tank 23 and the anaerobic tank 24 is as shown in (6) and (7) of FIG. In addition, the function of (25) (26) (27) (28) and (29) is the same as the function of (8) (9) (10) (11) and (12) of FIG.

Figure 3 is a biological aerobic tank / degassing tank / anaerobic tank / anaerobic / aerobic tank (ODA ² O) sequential wastewater treatment plan (35) (36) (37) function of Figure 1 (1) (2) (3) Same as In general, when the concentration of organic matter in the waste water is low or when the concentration of organic matter is greatly reduced by physicochemical pretreatment, a degassing tank 39 is installed at the front of the anaerobic tank 40 and the anoxic tank 41 and the aerobic tank at the front of the degassing tank 39. The provision of (38) to oxidize ammonia nitrogen to nitrate nitrogen as shown in schemes (1) and (2) effectively removes ammonia nitrogen. At this time, an aerobic tank should be installed at the rear end of the anaerobic tank 41 in order to increase the efficiency of removing phosphoric acid phosphorus simultaneously. The functions of the remaining (49) 50 and 51 are the same as or similar to the functions of (14) and (15) of FIG. And the roles of (43) (44) (45) 46 and 47 are the same as the functions of (8) (9) (10) (11) and (12) of FIG.

4 is a plan view of a biological anaerobic tank / aerobic tank / degassing tank / anaerobic tank / oxygen / aerobic tank (AODA ² O) sequential wastewater treatment (53) (54) and (55), respectively, (1) (2) and (3) of FIG. Is the same as). In general, when the concentration of organic matter in the waste water is high, the anaerobic tank 56 is attached to the front end of the aerobic tank 38 of FIG. 3 to decompose organic matter anaerobic to reduce the load of the aerobic tank 57 in the next step. At this time, a degassing tank 58 should be installed at the front end of the anaerobic tank 59 to prevent the killing of anaerobic bacteria in the anaerobic tank. Reference numeral 67 is the same as 30 in FIG. 2, and the functions 60 and 72 correspond to those in FIGS. 3 to 52 in FIG. 3. Sequential biological wastewater treatment as shown in Figure 4 is the most effective method for biological treatment of ammonia nitrogen and phosphate phosphorus when the concentration of organic matter in the waste water.

Highly efficient removal of nitrogen and phosphorus from wastewater containing high concentrations of ammonia nitrogen and phosphate phosphorus, such as manure, landfill leachate and livestock waste, which are generally biologically difficult to treat, and organic matter contained in the waste. The effect of developing nitrogen alone or nitrogen and phosphorus at the same time according to the concentration of was obtained. Referring specifically to the effects of the invention as follows.

In order to biologically remove ammonia nitrogen (NH ₃ -N) and phosphate phosphorus (PO ₄ -P) such as high concentrations of manure, landfill leachate, and livestock wastewater, which have very high concentrations of organic matter, To treat these wastewaters by the so-called A ² O process of digesting and sequentially installing anaerobic tanks and aerobic tanks. ) Oxidation to nitric ions (NO ₃ ⁻ ) takes place in an aerobic tank where the nitrate ions are reduced to nitrogen and oxygen in the anaerobic and anaerobic tanks. Therefore, the current anaerobic / aerobic tank / aerobic tank (A ² O) process is an aerobic / degassed tank in which the deaeration tank is added to the reverse A ² O process in front of the anaerobic tank when the concentration of the wastewater mentioned above is dilute to achieve an effective denitrification reaction. / Anaerobic tank / anaerobic tank (ODA ² ) method should be changed. If the concentration of wastewater is high, the anaerobic tank / aerobic tank / degassing tank / anaerobic tank / anoxic tank (AODA ² ) method should be replaced with the anaerobic tank prior to the ODA ² method. Since phosphorus is absorbed in an aerobic tank and released in an anaerobic or anoxic tank, it is necessary to remove ammonia nitrogen and phosphorus phosphorus dissolved in the waste water at the same time when the concentration of the waste water is dilute when the aerobic tank / degassing tank / anaerobic tank / anoxic tank (ODA ² ) The aerobic tank / degassing tank / anaerobic tank / anaerobic tank / aerobic tank (ODA ² O) method with the addition of an aerobic tank at the end of the process should be used, and if the concentration of waste water is high, the anaerobic tank / aerobic tank / deaeration with the aerobic tank connected to the latter part of AODA ² process The effect of the invention that the basal / anaerobic / anaerobic / aerobic (AODA ² O) method is the most suitable method has been obtained.

Claims (4)

A method of treating wastewater with an aerobic / degassing / anaerobic / oxygen tank (ODA ² ) method which has a low concentration of waste water and effectively removes ammonia nitrogen from the waste water. A method of treating wastewater by an anaerobic / aerobic / degassing / anaerobic / anoxic tank (AODA ² ) method which has a high concentration of wastewater and effectively removes ammonia nitrogen from the wastewater. A method of treating wastewater with an aerobic / degassing / anaerobic / anoxic / aerobic (ODA ² O) process that has a low concentration of waste water and effectively removes ammonia nitrogen and phosphorus phosphorus in the waste water. A method of treating wastewater with an anaerobic / aerobic / degassing / anaerobic / aerobic / aerobic (AODA ² O) process, which has a high concentration of wastewater and effectively removes ammonia nitrogen and phosphorus phosphorus in the wastewater.