TW201908245A - Method and apparatus for preparing the influent of anaerobic ammonia oxidation - Google Patents

Abstract

This invention is a method and the application for preparing the influent of anaerobic ammonia oxidation (ANAMMOX) treatment. It includes a partial nitrification bioreactor where the ammonia is oxidized to nitrite by ammonia oxidation bacteria. By detecting the concentration of nitrous oxide (N2O), which is a byproduct of ammonia oxidation, as a tool to control the operation of partial nitrification. When the generation of N2O reaches a certain point, the aeration shuts off. At this point, the ratio of ammonia to nitrite is suitable for ANAMMOX treatment. By this way, the influent of ANAMMOX is prepared in a single reactor.

Description

 Method and device for preparing anaerobic ammonium oxidation reaction inflow water  

The invention belongs to the technical field of sewage treatment, and relates to a method and a device for ammoxidation reaction, in particular to a method and a device for preparing an inflow water of an anaerobic ammonium oxidation reaction.

The removal of ammonia nitrogen (NH ₃ -N) in conventional wastewater is commonly carried out by nitrification and denitrification. Nitrification converts environmentally harmful ammonia nitrogen into more stable nitrates (nitrate, NO ₃ ^- ) through autotrophic microorganisms. However, nitrates still cause eutrophication in environmentally tolerant water bodies. Potential crises must be further reduced to nitrogen by denitrification and spilled into the atmosphere. Nitrification involves two main steps. First, ammonia oxidation bacteria first oxidize ammonia nitrogen to nitrite (NO ₂ ^- ) (chemical formula (1) to (3)), and then oxidize by nitrite. Nitrite oxidation bacteria oxidize nitrite to nitrate (chemical formulas (4) to (5)). Denitrification is the decomposition of organic matter by heterotrophic microorganisms in the absence of oxygen, with nitrate or nitrous acid as the electron acceptor. The nitrate is first reduced to nitrite, and then sequentially reduced to nitric oxide, nitrous oxide and finally nitrogen. The overall reaction formula is as shown in chemical formula (6).

NH ₃ +O ₂ +2 H ⁺ +2 e ^- → NH ₂ OH+H ₂ O.....................(1)

NH ₂ OH+H ₂ O → HNO ₂ +4 H ⁺ +4 e ^- ........................(2)

0.5 O ₂ +2 H ⁺ +2 e ^- → H ₂ O....................................(3)

HNO ₂ +H ₂ O → HNO ₃ +2 H ⁺ +2 ^e -...........................(4)

0.5 O ₂ +2 H ⁺ +2 e ^- → H ₂ O.......................................(5)

6NO ₃ ^- +5CH ₃ OH → 3N ₂ +5CO ₂ +7H ₂ O+6 OH ^- ............(6)

The above treatment method is in line with the principle of natural carbon cycle and is the most commonly used ammonia nitrogen treatment method. However, the nitrification process needs to provide sufficient oxygen to allow the reaction to proceed smoothly. Nitrification of 1 gram of nitrogen in the form of ammonia nitrogen to nitrogen in the form of nitrates requires 4.6 grams of oxygen to be consumed at the theoretical dose. In addition to this, it is also necessary to consume a theoretical dose of 7.1 grams of calcium carbonate equivalent alkalinity. Whether it is the energy consumption of oxygen supply or the additional cost of medicine required to maintain alkalinity, the cost of biological nitrification of sewage is high. In terms of denitrification, sufficient carbon source is the key to denitrification. In the case of insufficient carbon source, it is often necessary to add additional carbon source. One gram of nitrogen in the form of nitrate is reduced to nitrogen by denitrification. A theoretical equivalent of 1.9 grams of methanol is required. Whether it is nitrification or denitration, the treatment cost of sewage is greatly increased.

In the late 1990s, Dutch scientists and engineers discovered a biological reaction program that oxidized ammonia nitrogen with nitrite to form nitrogen and a small amount of nitrate (chemical formula (7)) under anaerobic conditions. Reduce the cost of ammonia nitrogen treatment. Since ammonia nitrogen occurs in the absence of oxygen, it is called anaerobic ammonia oxidation (ANAMMOX).

1 NH ₄ ⁺ +1.32 NO ₂ ^- +0.066 HCO ₃ ^- +0.13 H ⁺ → 1.02 N ₂ +0.26

NO ₃ ^- +0.066 CH ₂ O _0.5 N _0.15 +2.03 H ₂ O...........................(7)

In the actual application of the above ANAMMOX, it is necessary to provide influent wastewater rich in nitrous acid and react with ammonia nitrogen. Alternatively, the reaction control must be stopped in the first step of ammonia oxidation during the ammonia nitrogen nitration process, so that the product stays in the nitrite and no longer enters the nitrite oxidation to be converted into nitrate. Since this is an incomplete nitrification, it is also called local nitrification.

At present, the actual engineering application of anaerobic ammonium oxidation is generally based on the theoretical molar ratio of chemical formula (7). Part of the ammonia nitrogen wastewater (about 55%) is treated by local nitrification, and the treated water and the remaining ammonia nitrogen are used. Waste water (about 45%) is mixed into the ANAMMOX reaction tank for anaerobic ammonium oxidation. This method requires the installation of a local nitrification reaction tank to increase the construction cost of the wastewater treatment system and the required land space.

In view of the above disadvantages of the prior art, the main object of the present invention is to provide a method and a device for preparing an inflowing water of an anaerobic ammonium oxidation reaction, and monitoring the concentration of nitrous oxide produced during the nitrification process as a control method for completing the local nitrification reaction. The preparation of the anaerobic ammonium oxidation reaction feed water can be carried out in the same reaction tank to enter the subsequent ANAMMOX treatment.

In order to achieve the above object, the present invention provides a method for preparing an anaerobic ammonium oxidation reaction influent water, comprising cultivating biomass in a biological reaction tank, injecting ammonia-containing wastewater into a biological reaction tank, and adding an oxygen-containing gas to the biological reaction tank. Ammoxidation reaction, oxidizing ammonia nitrogen in the nitrogen-containing wastewater to nitrite, and detecting the concentration of nitrous oxide produced by the ammoxidation reaction, and stopping the addition of the oxygen-containing gas when the nitrous oxide concentration reaches a reaction control point, The preparation of the influent water of the anaerobic ammonium oxidation reaction is completed.

The invention further provides a device for preparing an anaerobic ammonium oxidation reaction inflow water, comprising a biological reaction tank for accommodating ammonia-containing wastewater and biomass to perform local ammoxidation reaction, and an aeration control device aeration control device The utility model comprises an aeration device for adding an oxygen-containing gas to the biological reaction tank, the nitrous oxide concentration detecting device, and the data transmission medium is connected with the aeration control device, and comprises a nitrous oxide concentration detector. The nitrous oxide concentration generated by the ammonia oxidation aeration reaction and the nitrous oxide concentration aeration control unit are connected to the nitrous oxide concentration detector by the data transmission medium for receiving the nitrous oxide concentration detection The nitrous oxide concentration data transmitted by the device determines that when the nitrous oxide concentration reaches the reaction control point, the stop aeration signal is transmitted to the aeration control device, and the oxygen-containing gas is stopped in the biological reaction tank.

Among them, nitrous oxide is a colorless and odorless gas, which is produced by oxidation of NH ₂ OH during the ammoxidation process. Because of its low water solubility, it is easy to overflow into the air under aeration. The nitrous oxide dissolved in water is subjected to the action of microorganisms and continues to oxidize to form nitric oxide (NO), which is a highly unstable compound and is easily oxidized to nitrous acid. Therefore, the concentration of nitrous oxide is affected by two factors: one is the concentration of ammonia nitrogen, which determines the production rate of nitrous oxide; the other is the rate of nitrite formation, which determines the reduction rate of nitrous oxide. When the two reach equilibrium, the concentration of nitrous oxide begins to decrease, and the concentration of ammonia nitrogen in water is slightly lower than that of nitrous acid, which is close to the chemical dose ratio of anaerobic amine oxidation (chemical reaction formula (7)). Can be used as a reaction stop point for the preparation of ANAMMOX influent water. When the nitrous oxide control device analyzes the peak point of N ₂ O, it is communicated to the aeration control device to terminate the aeration device to continue supplying oxygen to the reaction tank. The residual oxygen continues to undergo local ammoxidation under the action of microorganisms until the oxygen is depleted. The ammonia nitrogen in the treated water is further reduced and the nitrite is increased, and the ratio between the two is closer to the theoretical dose ratio.

S110‧‧‧ Process steps

S120‧‧‧ Process steps

S130‧‧‧ Process steps

S140‧‧‧ Process steps

S210‧‧‧ Process steps

S220‧‧‧ Process steps

S310‧‧‧ Process steps

S320‧‧‧ Process steps

S410‧‧‧ Process steps

S420‧‧‧Steps

510‧‧‧Bioreactor

520‧‧‧Biomass

530‧‧‧Aeration control device

540‧‧‧Aeration device

550‧‧‧ nitrous oxide concentration detection device

560‧‧‧ nitrous oxide concentration detector

570‧‧‧ nitrous oxide concentration control unit

610‧‧‧Dissolved oxygen quantity control device

620‧‧‧pH control device

630‧‧‧Sludge discharge device

710‧‧‧Regulation tank

720‧‧‧Oxygen-free ammonia oxidation reactor

The first figure is a flow chart of the process of the anaerobic ammonium oxidation reaction inflow water according to an embodiment of the present invention.

The second figure is a flow chart of the inflowing water process of the anaerobic ammonium oxidation reaction according to an embodiment of the present invention.

The third figure is a flow chart of the inflowing water process of the anaerobic ammonium oxidation reaction according to an embodiment of the present invention.

The fourth figure is a flow chart of the inflowing water process of the anaerobic ammonium oxidation reaction according to an embodiment of the present invention.

The fifth figure is an architecture diagram of an anaerobic ammonium oxidation reaction inflow water preparation device according to an embodiment of the present invention.

The sixth figure is an architecture diagram of an anaerobic ammonium oxidation reaction influent water preparation device according to an embodiment of the present invention.

The seventh figure is an architecture diagram of an anaerobic ammonium oxidation reaction water inlet device according to an embodiment of the present invention.

The eighth figure shows the changes of ammonia nitrogen, nitrate, nitrite, total nitrogen and nitrous oxide over time in a batch reaction.

The embodiments of the present invention are described by way of specific examples, and those skilled in the art can readily understand the advantages and advantages of the present invention.

Embodiment 1 : Please refer to the first embodiment of the present invention for an anaerobic ammonium oxidation reaction inflow water process flow chart. The embodiment of the present invention is a method for preparing an anaerobic ammonium oxidation reaction influent water, which is included in a biological reaction tank. The biomass S110 is cultured, the ammonia-containing wastewater is injected into the biological reaction tank S120, the oxygen-containing gas S130 is added to the biological reaction tank, the ammonia oxidation reaction is performed, the ammonia nitrogen in the nitrogen-containing wastewater is oxidized to the nitrite S140, and the ammonia is detected. The nitrous oxide concentration produced by the oxidation reaction, when the nitrous oxide concentration reaches a reaction control point, stops the addition of the oxygen-containing gas, and completes the preparation of the anaerobic ammonium oxidation reaction influent water. In the embodiment of the present invention, the biomass is an ammonia oxidizing bacteria, and the method for detecting the nitrous oxide concentration generated by the ammoxidation reaction is to use a nitrous oxide detector. The control point is the time point at which the nitrous oxide concentration changes from an increase to a decrease in the ammoxidation reaction. The calculation method for converting the nitrous oxide concentration from an increase to a decrease time point is a mathematical method such as a maximum value method, a differential method or a tangent method. The method of adding an oxygen-containing gas is to use an aeration device such as a blower, an air compressor or a surface aerator to send an oxygen-containing gas, the oxygen-containing gas is air, and the data transmission medium can be wired or wireless data such as a network, a telecommunication, a point-to-point connection, or the like. Transmission system.

Embodiment 2: Referring to the second embodiment of the present invention, an anaerobic ammonium oxidation reaction inflow water process flow chart, in addition to the process steps of the first embodiment, the embodiment of the present invention further includes opening or closing the aeration device. The amount of oxygen-containing gas added is controlled to adjust the oxygen content S210 of the biological reaction tank.

Embodiment 3: Referring to the second embodiment of the present invention, an anaerobic ammonium oxidation reaction inflow water process flow chart, in addition to the process steps of the first embodiment, further includes controlling the acid in the biological reaction tank. The base value is between 6 and 9, and the pH of the alkalinity is beneficial to increase the oxidation rate of ammonia nitrogen to maintain the oxidation rate of ammonia nitrogen S220.

Embodiment 4: Referring to the third embodiment of the present invention, an anaerobic ammonium oxidation reaction inflow water process flow chart, in addition to the process steps of the first embodiment, the embodiment of the present invention further includes stopping the addition of the oxygen-containing gas. After aeration, the biological reaction tank is allowed to stand for a period of time, and the ammonia oxidation reaction is generated to cause the sludge to sink into the chamber S310 to achieve the effect of solid-liquid separation.

Embodiment 5: Please refer to the third embodiment of the flow chart of the anaerobic ammonium oxidation reaction inflow water according to an embodiment of the present invention. In addition to the process steps including the first embodiment, the embodiment of the present invention further includes discharging the excess sludge amount to maintain A certain amount of the biomass S320.

Embodiment 6: Referring to the fourth embodiment of the present invention, an anaerobic ammonium oxidation reaction inflow water process flow chart, in addition to the process steps of the first embodiment, the embodiment of the present invention further includes providing a mixing tank for providing The nitrogen-containing wastewater is injected into the homogenization tank before being injected into the homogenization tank to adjust the water quality of the nitrogen-containing wastewater and the water quantity control S410.

Embodiment 7: Please refer to the fourth embodiment of the flow chart of the anaerobic ammonium oxidation reaction inflow water according to an embodiment of the present invention. In addition to the process steps including the first embodiment, the embodiment of the present invention further includes preparing the prepared oxygen-free ammonia. The oxidation reaction influent water is injected into the anaerobic ammonium oxidation biological reaction tank to prepare the completed anaerobic ammonium oxidation reaction inflow water for the anaerobic ammonium oxidation reaction S420.

Embodiment 8: Referring to FIG. 5 is a structural diagram of an anaerobic ammonium oxidation reaction inflow water preparation device according to an embodiment of the present invention, the embodiment of the invention includes a biological reaction tank 510 for accommodating ammonia-containing wastewater and biomass 520, in order to perform a local ammoxidation reaction, an aeration control device 530, including an aeration device 540 for adding an oxygen-containing gas to the biological reaction tank 510; a nitrous oxide concentration detecting device 550 for data transmission The medium is connected to the aeration control device 530, and includes a nitrous oxide concentration detector 560 for detecting the nitrous oxide concentration generated by the ammonia oxidation aeration reaction, and the nitrous oxide concentration control unit 570 for the data transmission medium. The nitrous oxide concentration detector 560 is connected to receive the nitrous oxide concentration data transmitted by the nitrous oxide concentration detector 560, and determines that when the nitrous oxide concentration reaches the reaction control point, the aeration signal is sent to the aeration. Control device 530, aeration device 540 stops adding oxygen-containing gas to bioreactor 510. The biomass 520 is an ammonia oxidizing bacteria, the oxygen-containing gas is air, and the nitrous oxide concentration detector 560 is on-line to provide a control signal immediately, which may be a gas form detector or a liquid. Form detectors, gas pattern detectors can be detected by infrared (infra-red) absorption, ultraviolet (UV) absorption or cavity enhanced absorption spectroscopy (CEAS), liquid The detection principle of the detector is a gas chromatography (GC) method or a micro-sensor method, and the nitrous oxide concentration control unit 570 is an electronic calculator, and the reaction control point is The ablation device 540 is an aeration device such as a blower, an air compressor or a surface aeration for injecting air into the biological reaction tank 510 to provide a sufficient amount of oxygen.

Embodiment 9: Please refer to FIG. 6 for an architecture diagram of an anaerobic ammonium oxidation reaction inflow water preparation device according to an embodiment of the present invention. The embodiment of the present invention further includes a dissolved oxygen amount control device in addition to the device structure including the eighth embodiment. 610, to detect and control the oxygen content in the biological reaction tank 510. The dissolved oxygen amount control device 610 of the present embodiment is a dissolved oxygen meter (DO meter), and the control of the dissolved oxygen amount is controlled by the dissolved oxygen meter in the tank, and the dissolved oxygen in the reaction tank should be maintained enough for the local ammoxidation to continue. Not too high leads to oxidation of nitrite.

Embodiment 10: Please refer to FIG. 6 for an architecture diagram of an anaerobic ammonium oxidation reaction inflow water preparation device according to an embodiment of the present invention. The embodiment of the present invention further includes a pH control device in addition to the device structure including the eighth embodiment. 620, to detect and control the pH value in the biological reaction tank 510.

Embodiment 11: Please refer to FIG. 6 for an architecture diagram of an anaerobic ammonium oxidation reaction inflow water preparation device according to an embodiment of the present invention. The embodiment of the present invention further includes a sludge discharge device in addition to the device structure including the eighth embodiment. 630, for eliminating excess sludge generated, maintaining a certain amount of biomass 520 and sludge residence time in the biological reaction tank 510.

Embodiment 12: Please refer to the seventh embodiment of the present invention, which is an architecture of an anaerobic ammonium oxidation reaction inflow water preparation device. The embodiment of the present invention further includes a tempering tank 710 in addition to the device structure of the eighth embodiment. Before the biological reaction tank 510, before the nitrogen-containing wastewater enters the biological reaction tank 510, the quenching tank 710 is first introduced to perform water quality adjustment and water quantity control of the nitrogen-containing wastewater. The mixing tank 710 has the functions of adjusting the water quality and the amount of stored water. The pH required for local nitrification can be adjusted here, or can be carried out in the biological reaction tank 510. The waste water of the mixing tank 710 is mechanically or hydraulically. The wastewater is injected into the biological reaction tank 510, and the mixing tank 710 can be stirred by mechanical stirring, hydraulic stirring or gas stirring.

Embodiment 13: Referring to FIG. 7 is a structural diagram of an anaerobic ammonium oxidation reaction inflow water preparation device according to an embodiment of the present invention. The embodiment of the present invention further includes an anaerobic ammonium oxidation in addition to the device structure including the eighth embodiment. The reaction tank 720 is placed after the biological reaction tank 510 for accommodating the prepared anaerobic ammonium oxidation reaction feed water for the anaerobic ammonium oxidation reaction.

The above-described embodiments are merely illustrative of the features and functions of the present invention and are not intended to limit the scope of the technical scope of the present invention. Modifications and variations of the above-described embodiments can be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention should be as set forth in the scope of the claims described below.

Claims (21)

 A method for preparing an anaerobic ammonium oxidation reaction inflow water, comprising: (1) cultivating an ammonia oxidizing bacteria biomass in a biological reaction tank; (2) injecting an ammonia nitrogen-containing wastewater into the biological reaction tank; (3) Adding an oxygen-containing gas to the biological reaction tank to perform an ammoxidation reaction to oxidize ammonia nitrogen in the nitrogen-containing wastewater to nitrite; and (4) detecting the concentration of nitrous oxide produced by the ammoxidation reaction, when oxidizing The arsenic concentration reaches a reaction control point, that is, the addition of the oxygen-containing gas is stopped, and the preparation of the inflowing water of the anaerobic ammonium oxidation reaction is completed.    The method for preparing an anaerobic ammonium oxidation reaction inflow water as described in claim 1, wherein the method for detecting the nitrous oxide concentration produced by the ammoxidation reaction is to use a nitrous oxide detector.    The method for preparing an anaerobic ammonium oxidation reaction inflow water as described in claim 1, wherein the control point is a time point at which the nitrous oxide concentration changes from an increase to a decrease in the ammoxidation reaction.    The method for preparing an anaerobic ammonium oxidation reaction inflow water according to claim 1, wherein the method of adding the oxygen-containing gas is to use the aeration device such as a blower, an air compressor or a surface aerator to feed the oxygen-containing device. gas.    The method for preparing an anaerobic ammonium oxidation reaction inflow water according to claim 4, further comprising controlling the amount of the oxygen-containing gas to be added in a manner of opening or closing the aeration device to adjust the content of the biological reaction tank. Oxygen content.    The method for preparing an anaerobic ammonium oxidation reaction inflow water according to claim 1, further comprising controlling the pH value in the biological reaction tank to be between 6 and 9 to maintain the oxidation rate of the ammonia nitrogen.    The method for preparing an anaerobic ammonium oxidation reaction inflow water according to claim 1, further comprising: after stopping the addition of the oxygen-containing gas, allowing the biological reaction tank to stand for a period of time to allow the ammonia oxidation reaction to occur. The sludge sinks the temple.    The method for preparing an anaerobic ammonium oxidation influent water as described in claim 7, further comprising discharging the excess sludge amount to maintain a certain amount of the biomass.    The method for preparing an anaerobic ammonium oxidation reaction inflow water according to claim 1, further comprising providing a tempering tank, and the nitrogen-containing wastewater is injected into the smelting tank to perform the nitrogen-containing wastewater before being injected into the biological reaction tank. Water quality adjustment and water volume control.    The method for preparing an anaerobic ammonium oxidation reaction inflow water as described in claim 1, further comprising injecting the prepared anaerobic ammonium oxidation reaction influent water into an anaerobic ammonium oxidation reaction tank for an anaerobic ammonium oxidation reaction.    The invention relates to a device for preparing an inflow water of an anaerobic ammonium oxidation reaction, comprising: (1) a biological reaction tank for containing ammonia-nitrogen wastewater and an ammonia-oxidizing bacteria biomass for ammoxidation; (2) an aeration The control device comprises an aeration device for adding an oxygen-containing gas, a nitrous oxide concentration detecting device to the biological reaction tank, and the data transmission medium is connected to the aeration control device, including a nitrous oxide concentration a detector for detecting a concentration of nitrous oxide produced by the ammoxidation reaction, and a nitrous oxide concentration control unit coupled to the nitrous oxide concentration detector by a data transmission medium for receiving the nitrous oxide concentration The nitrous oxide concentration data transmitted by the detector determines that when the nitrous oxide concentration reaches a reaction control point, the stop aeration signal is transmitted to the aeration control device, and the oxygen-containing gas is stopped in the biological reaction tank.    The apparatus for preparing an anaerobic ammonium oxidation reaction inflow water according to claim 11, wherein the nitrous oxide concentration detector is a gas form detector or a liquid form detector.    The apparatus for preparing an anaerobic ammonium oxidation reaction inflow water as described in claim 12, wherein the gas form detector is detected by infrared light absorption, ultraviolet light absorption or cavity enhanced absorption spectrum.    The apparatus for preparing an anaerobic ammonium oxidation reaction inflow water as described in Patent Application No. 12, wherein the detection principle of the liquid detector is a gas chromatography method or a microelectrode method.    The apparatus for preparing an anaerobic ammonium oxidation reaction inflow water according to the invention of claim 11, wherein the reaction control point is a time point at which the nitrous oxide concentration is changed from an increase to a decrease.    The apparatus for preparing an anaerobic ammonium oxidation reaction inflow water as described in claim 11, wherein the aeration device is an aeration device such as a blower, an air compressor or a surface aeration.    The apparatus for preparing an anaerobic ammonium oxidation reaction inflow water according to claim 11 further includes a dissolved oxygen amount controlling device for detecting and controlling the oxygen content in the biological reaction tank.    The apparatus for preparing an anaerobic ammonium oxidation influent water according to claim 11 further comprises a pH control device for detecting and controlling the pH value in the biological reaction tank.    The apparatus for preparing an anaerobic ammonium oxidation reaction inflow water as described in claim 11 further comprises a sludge discharge device for discharging excess sludge after completion of the sludge septic chamber produced by the ammoxidation reaction.    The apparatus for preparing an anaerobic ammonium oxidation reaction inflow water according to claim 11, further comprising a tempering tank for entering the conditioned tank for nitrogen before the nitrogen-containing wastewater enters the biological reaction tank Wastewater quality adjustment and water volume control.    The apparatus for preparing an anaerobic ammonium oxidation reaction inflow water according to claim 11, further comprising an anaerobic ammonium oxidation reaction tank for accommodating the prepared anaerobic ammonium oxidation reaction inflow water for anaerobic treatment Ammoxidation reaction.