Wastewater anammox denitrification device

Abstract

The application discloses a wastewater anaerobic ammonia oxidation denitrification device, which comprises a reaction tank, a gas inlet pipe and a separator. The reaction tank is provided with a liquid inlet close to the tank bottom, and the liquid inlet is used for conveying wastewater. The gas inlet pipe is installed on the reaction tank, and the gas outlet of the gas inlet pipe is located at the middle position of the reaction tank. The gas conveyed by the gas inlet pipe moves to the top of the tank under the action of the liquid level, and the reaction tank can be divided into an aerobic reaction zone located at the upper part and an anaerobic reaction zone located at the lower part. The separator is installed on the top of the reaction tank and comprises a gas guide cover, a stripping pipe, a reflux pipe and a gas release tank, and the cover opening of the gas guide cover faces downward. The stripping pipe is connected with the gas guide cover and the gas release tank, and the top of the gas release tank is provided with a gas outlet. One end of the reflux pipe is connected with the gas release tank, and the other end penetrates through the top of the reaction tank and extends to the lower part of the gas inlet pipe. In this way, the aerobic reaction zone, the anaerobic reaction zone and the separator can be integrated in the reaction tank, so that the land occupation area of the wastewater anaerobic ammonia oxidation denitrification device is reduced.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of wastewater treatment, and particularly relates to a wastewater anaerobic ammonia oxidation denitrification device. BACKGROUND

[0002] The biological denitrification technology is a process of converting anaerobic ammonia nitrogen in wastewater into nitrogen gas through the action of microorganisms. In the prior art, the wastewater anaerobic ammonia nitrogen denitrification device comprises a reactor, a sedimentation tank and a reflux pump, the reflux pump is used for connecting the reactor and the sedimentation tank, and the reactor, the sedimentation tank and the reflux pump are separately arranged, thereby occupying a large area. SUMMARY

[0003] In order to solve the technical problem of large area occupation caused by the separate arrangement of each structure of the biological denitrification in the related art, the application provides a wastewater anaerobic ammonia oxidation denitrification device.

[0004] The application provides a wastewater anaerobic ammonia oxidation denitrification device, characterized in that the wastewater anaerobic ammonia oxidation denitrification device comprises:

[0005] A reaction tank is provided with a liquid inlet, and the liquid inlet is close to the tank bottom of the reaction tank;

[0006] A gas inlet pipe is installed in the reaction tank, and the gas outlet of the gas inlet pipe is located at the middle position of the reaction tank;

[0007] A separator is installed on the tank top of the reaction tank and comprises a gas guide cover, a stripping pipe, a reflux pipe and a gas release tank, the cover opening of the gas guide cover faces downward, one end of the stripping pipe is in communication with the gas guide cover, the other end of the stripping pipe is in communication with the gas release tank, the tank top of the gas release tank is provided with a gas outlet, one end of the reflux pipe is in communication with the gas release tank, and the other end of the reflux pipe penetrates through the tank top of the reaction tank and extends to below the gas inlet pipe.

[0008] In some embodiments, the wastewater anaerobic ammonia oxidation denitrification device further comprises:

[0009] A plurality of water inlet distributors are uniformly distributed in the reaction tank;

[0010] A water inlet pipe is provided with a same number of water outlets as the number of water inlet distributors, the water outlets are all located in the reaction tank, the water outlets of the water inlet pipe are in one-to-one communication with the water inlet distributors, the water inlet pipe is arranged in the liquid inlet, and the water inlet of the water inlet pipe is located outside the reaction tank.

[0011] In some embodiments, the wastewater anaerobic ammonia oxidation denitrification device further comprises:

[0012] A plurality of backflow water distributors are located in the reaction tank and are in communication with the one end of the backflow pipe away from the gas release tank, and the outlet of the backflow water distributor faces the water inlet distributor.

[0013] In some embodiments, the water inlet distributor is staggered with the backflow water distributor.

[0014] In some embodiments, the wastewater anammox denitrification device further comprises:

[0015] A plurality of aerators are in communication with the gas inlet pipe and are located in the reaction tank.

[0016] In some embodiments, the wastewater anammox denitrification device comprises:

[0017] A dissolved oxygen detector is installed in the reaction tank and is located outside the reaction tank, and the dissolved oxygen detector is in communication with a detection space in the reaction tank, wherein the detection space is located between the aerator and the top of the reaction tank.

[0018] In some embodiments, a plurality of gas guide covers are provided, and the plurality of gas guide covers are arranged in a matrix in the cross section of the reaction tank; the gas guide cover is provided with multiple layers, and the multiple layers of the gas guide cover are staggered and partially overlapped in the vertical direction.

[0019] In some embodiments, the separator further comprises:

[0020] A plurality of layers of inclined plates are installed on the outer side of the gas guide cover away from the cover opening;

[0021] A water outlet weir is located above the gas guide cover, is installed on the inner side wall of the reaction tank and is close to the top of the reaction tank, the side wall of the reaction tank is provided with a drainage opening, and the drainage opening is in communication with the water outlet weir.

[0022] In some embodiments, the water outlet weir is annular and is installed on the inner side wall of the reaction tank around the axis of the reaction tank.

[0023] In some embodiments, the reaction tank is provided with a sludge discharge hole near the bottom of the tank.

[0024] According to one or more embodiments of the present application, a wastewater anaerobic ammonia oxidation denitrification device is provided, which comprises a reaction tank, an air inlet pipe and a separator. The reaction tank is provided with a liquid inlet for conveying wastewater, and the liquid inlet is close to the bottom of the reaction tank, so that the wastewater can enter the reaction tank from the liquid inlet at the lower part of the reaction tank. The air inlet pipe is installed in the reaction tank, and the air outlet of the air inlet pipe is located at the middle position of the reaction tank, so that the air entering the reaction tank through the air inlet pipe can react with the waste liquid in the reaction tank to generate nitrite, and the air not participating in the reaction will form bubbles and gradually move upward due to its smaller density than the wastewater. The separator is installed on the top of the reaction tank and comprises a gas guide cover, a stripping pipe, a reflux pipe and a gas release tank. The cover of the gas guide cover faces downward, so that the upward moving bubbles are collected by the gas guide cover and move upward along the gas guide cover. One end of the stripping pipe is communicated with the gas guide cover, and the other end is communicated with the gas release tank, so that the bubbles collected by the gas guide cover and the waste liquid containing nitrite move along the stripping pipe to the gas release tank. Since the top of the gas release tank is provided with an exhaust port, the gas in the bubbles is discharged along the exhaust port. One end of the reflux pipe is communicated with the gas release tank, and the other end penetrates through the top of the reaction tank and extends below the air inlet pipe. The waste liquid containing nitrite moving to the gas release tank moves along the reflux pipe to the anaerobic reaction zone below the air inlet pipe, and reacts with the wastewater to generate nitrogen gas, which forms bubbles and moves along the stripping pipe to the gas release tank together with the air not participating in the reaction, and is discharged from the exhaust port.

[0025] Compared with the prior art, since the separator, the anaerobic reaction zone and the aerobic reaction zone are integrated on one reaction tank in the present application, multiple functions are realized, so that the device occupies less space, has a compact structure and is rich in functions. Since multiple functions are integrated in the reaction tank, the movement path of the wastewater is shortened, and the efficiency of the wastewater anaerobic ammonia oxidation denitrification is improved. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 FIG. 1 is a structural schematic diagram of a wastewater anaerobic ammonia oxidation denitrification device according to one or more embodiments of the present application.

[0027] BRIEF DESCRIPTION OF DRAWINGS

[0028] 10, reaction tank; 11, bottom plate; 12, wall plate; 121, liquid inlet; 13, top plate; 14, sludge discharge hole; 15, sludge discharge valve; 16, water outlet;

[0029] 20, air inlet pipe; 21, air inlet valve;

[0030] 30, separator; 31, gas guide cover; 311, lower support; 312, upper support; 32, stripping pipe;

[0031] 33, reflux pipe; 34, gas release tank; 341, first support; 342, exhaust port; 35, multi-layer inclined plate;

[0032] 36, water outlet weir;

[0033] 40, water inlet distributor; 41, second support;

[0034] 50, water inlet pipe; 51, water inlet valve;

[0035] 60, reflux distributor; 61, third support;

[0036] 70, aerator; 71, fourth support;

[0037] 80, dissolved oxygen detector; 81, instrument valve;

[0038] A, aerobic reaction zone; B, anaerobic reaction zone. DETAILED DESCRIPTION

[0039] In order for those skilled in the art to which the present application pertains to more clearly understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0040] Biological denitrification technology is a process of converting anaerobic ammonia nitrogen in wastewater into nitrogen gas through microbial action. The traditional biological denitrification technology is mainly based on nitrification and denitrification, and uses nitrifying bacteria and denitrifying bacteria to remove nitrogen in wastewater. Nitrification is a process of oxidizing ammonia nitrogen in wastewater into nitrate under aerobic conditions through the action of nitrifying bacteria. Nitrification includes two processes, one of which is to convert ammonia nitrogen in wastewater into nitrite through the action of nitrite bacteria, and the other of which is to convert nitrite in wastewater into nitrate through the action of nitrifying bacteria. Denitrification is a process of converting nitrite in wastewater into nitrogen gas through the action of denitrifying bacteria under anoxic conditions and sufficient carbon source.

[0041] In the prior art, the wastewater anaerobic ammonia nitrogen denitrification device includes a reactor, a sedimentation tank and a reflux pump, the reflux pump is used to communicate the reactor and the sedimentation tank, and the reactor, the sedimentation tank and the reflux pump are separately provided, thereby occupying a large area.

[0042] To solve the technical problem of large occupied area of the wastewater anaerobic ammonia nitrogen denitrification device in the related art, the application provides a wastewater anaerobic ammonia oxidation denitrification device. The anaerobic ammonia oxidation reaction is a process of converting nitrite and ammonia nitrogen into nitrogen under anaerobic conditions through the action of anaerobic ammonia oxidation bacteria, with nitrite and ammonia nitrogen as substrates.

[0043] Please refer to Figure 1 The wastewater anaerobic ammonia oxidation denitrification device comprises a reaction tank 10, a gas inlet pipe 20 and a separator 30.

[0044] The reaction tank 10 can be used as a mounting base, and the cavity in the reaction tank 10 can be used as an anaerobic ammonia oxidation denitrification reaction chamber. The reaction tank 10 comprises a bottom plate 11, a top plate 13 and a plurality of wall plates 12. The bottom plate 11 and the top plate 13 are arranged in a vertical direction. The wall plates 12 are arranged on opposite sides in the vertical direction and are connected to the bottom plate 11 and the top plate 13, respectively. The plurality of wall plates 12 are sequentially and end-to-end closed and connected. In this way, the bottom plate 11, the top plate 13 and the plurality of wall plates 12 form a revolving body. The axial direction of the revolving body extends in the vertical direction. The shape of the reaction tank 10 can be cylindrical, conical or prismatic. When the reaction tank 10 is cylindrical, the size of the reaction tank 10 in the vertical direction is greater than 2 times the diameter of the bottom wall of the reaction tank 10. That is, the height of the wall plate 12 in the vertical direction is greater than 2 times the diameter of the bottom plate 11, so as to facilitate the arrangement of the first reaction zone and the second reaction zone distributed in the vertical direction. In other embodiments, the size of the reaction tank 10 can be set according to actual needs, which is not limited in the application. The material of the reaction tank 10 can be metal, such as stainless steel and carbon steel. The reaction tank 10 is provided with a liquid inlet 121 for conveying wastewater into the reaction tank 10. Specifically, the liquid inlet 121 is arranged on the wall plate 12 and is close to the bottom of the reaction tank 10, that is, the liquid inlet 121 is close to the bottom plate 11, so as to facilitate the conveying of wastewater from the bottom of the reaction tank 10 into the reaction tank 10 and the lifting of the wastewater in the vertical direction in the reaction tank 10. It should be noted that the wastewater treated by the wastewater anaerobic ammonia oxidation denitrification device can be ammonia nitrogen industrial wastewater or landfill leachate, or other types of wastewater, which is not limited in the application.

[0045] Please refer to Figure 1The air inlet pipe 20 is used to introduce air into the reaction tank 10 to participate in the denitrification reaction of anaerobic ammonia nitrogen in the wastewater. The air inlet pipe 20 is installed in the reaction tank 10. The air inlet pipe 20 passes through the wall panel 12 of the reaction tank 10. The air inlet of the air inlet pipe 20 is located outside the reaction tank 10 and is used to communicate with the air source. The air outlet of the air inlet pipe 20 is located in the reaction tank 10 and can provide air (air contains oxygen) to the reaction tank 10. The air inlet pipe 20 is located in the vertical middle of the reaction tank 10, that is, between the separator 30 and the bottom of the reaction tank 10. This divides the chamber inside the reaction tank 10 into a first reaction zone located between the separator 30 and the air inlet pipe 20 and a second reaction zone located between the air inlet pipe 20 and the bottom of the reaction tank 10. The liquid inlet 121 is connected to the second reaction zone. Therefore, when wastewater is transported to the second reaction zone in the reaction tank 10 through the liquid inlet 121, an anaerobic reaction occurs, producing nitrogen. Therefore, the second reaction zone can be used as the anaerobic reaction zone B. After the anaerobic reaction, the wastewater continues to move upward to the second reaction zone. The air discharged from the air outlet of the air inlet pipe 20 moves upward due to the buoyancy of the wastewater, reacting aerobically with the wastewater in the first reaction zone to form nitrite. Therefore, the first reaction zone can be used as the aerobic reaction zone A.

[0046] See also Figure 1 The separator 30 is used to separate the nitrite formed in the first reaction zone, i.e., the aerobic reaction zone A, from the generated gas, and to return the separated nitrite to the second reaction zone, i.e., the anaerobic reaction zone B. The separator 30 is mounted on the top of the reaction tank 10 and includes an air guide hood 31, a stripping pipe 32, a reflux pipe 33, and a gas release tank 34.

[0047] The opening of the air hood 31 faces downward and is used to collect bubbles in the wastewater (bubbles formed by the nitrogen generated in the anaerobic reaction zone B and the air introduced through the air inlet pipe 20 that does not participate in the oxidation reaction). The stripping pipe 32 is installed through the top plate 13. One end of the stripping pipe 32 is connected to the outlet of the air hood 31, and the other end is connected to the gas release tank 34. The gas release tank 34 has an exhaust port 342 opened on the tank top. The return pipe 33 is installed through the top plate 13. One end of the return pipe 33 is connected to the gas release tank 34, and the other end extends to the bottom of the reaction tank 10. In other words, the other end of the return pipe 33 is installed through the tank top of the reaction tank 10 and extends to the bottom of the reaction tank 10 below the air inlet pipe 20, close to the tank bottom of the reaction tank 10. That is, the other end of the return pipe 33 is located in the first reaction zone. The gas release tank 34 is located outside the reaction tank 10 and is supported on the top plate 13 by a first bracket 341 . The first bracket 341 is used to support the gas release tank 34 to improve the stability of the position of the gas release tank 34 in the reaction tank 10 .

[0048] The air inlet of the air inlet pipe 20 is located outside the reaction tank 10, so that the air blower can deliver air into the reaction tank 10 through the air inlet pipe 20. In this way, the separator 30, the air inlet pipe 20 and the liquid inlet 121 are sequentially arranged in the reaction tank 10 from top to bottom.

[0049] The working process of the wastewater anammox denitrification device is as follows: the wastewater containing anammox to be treated continuously enters the anoxic reaction zone B of the reaction tank 10 from the liquid inlet 121. As the liquid level in the reaction tank 10 rises, the liquid surface of the wastewater gradually submerges the air inlet pipe 20 and rises to the aerobic reaction zone A. The sludge in the wastewater contains nitrosobacteria, and the air continuously delivered by the air inlet pipe 20 is dissolved in the wastewater to provide an aerobic environment for the reaction of the nitrosobacteria. The nitrosobacteria convert the anammox in the aerobic reaction zone A into nitrite, and the reaction stoichiometric formula is as follows:

[0050]

[0051] As the liquid level in the reaction tank 10 rises, the air bubbles formed by the dissolved air in the wastewater that does not participate in the oxidation reaction can gather in the gas guide cover 31. Since the gas guide cover 31, the stripping pipe 32 and the gas release tank 34 are sequentially connected, the gas in the gas guide cover 31 can move to the gas release tank 34. Since the internal space of the gas release tank 34 is large, when the bubbles are transported into the gas release tank 34 through the stripping pipe 32, the pressure of the bubbles decreases, the bubbles burst, the gas in the bubbles is released and discharged from the exhaust port 342. The gas discharged from the exhaust port 342 includes carbon dioxide and a small amount of oxygen, etc., and these gases can be released into the atmosphere. Since the gas guide cover 31 is immersed in the wastewater, the wastewater (containing a large amount of NH4 + , etc.) in the aerobic reaction zone A can also move along the stripping pipe 32 to the gas release tank 34. The reaction solution (including NH4 + , etc.) gathers at the bottom of the gas release tank 34 under the action of gravity and moves along the reflux pipe 33 to the anoxic reaction zone B of the reaction tank 10 to participate in the anoxic reaction, so that the separation of the gas and the reaction solution can be realized.

[0052] The reflux solution is delivered to the bottom of the reaction tank 10 through the reflux pipe 33, and the reflux solution can be mixed with the wastewater in the anoxic reaction zone B. The sludge in the wastewater contains anammox bacteria, and under the anoxic environment, the anammox bacteria convert the ammonia nitrogen and the nitrite into nitrogen gas, and the denitrification reaction stoichiometric formula is as follows:

[0053]

[0054] The liquid inlet 121 of the reaction tank 10 continuously inputs the wastewater, and the N2 (nitrogen) generated by the anaerobic reaction is dissolved in the wastewater to form nitrogen bubbles. As the liquid level in the reaction tank 10 rises, the wastewater gradually rises to the aerobic reaction area A. The nitrogen bubbles can gather in the gas guide cover 31 and be transported to the gas release tank 34 through the stripping pipe 32, and the nitrogen is discharged from the exhaust port 342 of the gas release tank 34.

[0055] It should be noted that for wastewater containing volatile organic components, the gas output through the exhaust port 342 needs to be introduced into the waste gas treatment process for treatment to prevent harmful substances in the gas from being released into the atmosphere and polluting the environment.

[0056] According to the position of the air inlet pipe 20 in the reaction tank 10 along the vertical direction, the reaction tank 10 can be divided into an aerobic reaction area A and an anaerobic reaction area B, and the aerobic reaction area A is located above the anaerobic reaction area B. In this way, the aerobic reaction area A, the anaerobic reaction area B, and the separator 30 can be integrated in the reaction tank 10, and the reflux pipe 33 is used instead of the reflux pump in the prior art in the present application, which reduces the floor area of the wastewater anaerobic ammonia oxidation denitrification device and also improves the efficiency of the wastewater anaerobic ammonia oxidation denitrification. Controlling the aerobic reaction and the anaerobic reaction in the reaction tank 10 respectively can improve the reaction efficiency and improve the denitrification efficiency.

[0057] In some embodiments, the diameter of the stripping pipe 32 is smaller than the diameter of the bubbles gathered in the gas guide cover 31. Since the diameter of the stripping pipe 32 is small and the diameter of the bubbles in the gas guide cover 31 is large, the bubbles will carry the reaction solution (including and NH4 + , etc.) produced by the aerobic reaction to the gas release tank 34 when passing through the stripping pipe 32.

[0058] In other embodiments, a power pump is connected between the stripping pipe 32 and the gas release tank 34, and the bubbles in the gas guide cover 31 and the wastewater containing and NH4 + , etc. are pumped into the gas release tank 34 by the power pump.

[0059] In order to accurately control the amount of air transported in the air inlet pipe 20, the air inlet pipe 20 is connected in series with an air inlet valve 21 for adjusting the flow in the air inlet pipe 20. The air inlet valve 21 is located outside the reaction tank 10 to facilitate adjustment of the flow of gas in the air inlet pipe 20. Specifically, the flow of air transported into the reaction tank 10 through the air inlet pipe 20 can be controlled by controlling the on-off and opening degree of the air inlet valve 21.

[0060] In order to mix the wastewater and the reflux solution sufficiently, please refer to Figure 1 , the wastewater anaerobic ammonia oxidation denitrification device further comprises a plurality of water inlet distributors 40 and water inlet pipes 50.

[0061] The water inlet pipe 50 is arranged in the liquid inlet 121, and the water inlet of the water inlet pipe 50 is located outside the reaction tank 10, so that the wastewater can be transported into the reaction tank 10 through the water inlet of the water inlet pipe 50. The water inlet distributor 40 is installed on the bottom plate 11 of the reaction tank 10 through the second support 41, and the second support 41 is used for supporting the water inlet distributor 40, so as to improve the position stability of the water inlet distributor 40 in the reaction tank 10. The plurality of water inlet distributors 40 are uniformly distributed on the bottom of the reaction tank 10, the water outlet of the water inlet pipe 50 is located in the reaction tank 10, and the water inlet pipe 50 is communicated with the water inlet distributor 40, so that the diffusion range of the wastewater in the bottom of the reaction tank 10 can be expanded, the contact area between the wastewater and the reflux solution can be increased, and the anaerobic reaction efficiency of the anaerobic reaction zone B can be improved. In order to accurately control the wastewater transportation amount in the water inlet pipe 50, the water inlet pipe 50 is connected with the water inlet valve 51, the water inlet valve 51 is located outside the reaction tank 10, and the amount of wastewater transported into the reaction tank 10 through the water inlet pipe 50 can be controlled by controlling the on-off of the air inlet valve 21.

[0062] In order to improve the mixing of the wastewater and the reflux solution, please refer to Figure 1 The wastewater anaerobic ammonia oxidation denitrification device also comprises a plurality of reflux distributors 60 and a reflux adapter pipe. The plurality of reflux distributors 60 are located in the reaction tank 10, the plurality of reflux distributors 60 are communicated with the one end of the reflux pipe 33 away from the gas release tank 34 through the reflux adapter pipe (not shown in the figure), and the outlet of the reflux distributor 60 faces the water inlet distributor 40. The plurality of reflux distributors 60 can expand the diffusion range of the reflux solution, increase the contact area with the wastewater, and improve the anaerobic reaction efficiency of the anaerobic reaction zone B. The plurality of reflux distributors 60 can be respectively communicated with the reflux pipe 33 through the reflux adapter pipe, so as to facilitate the arrangement of the plurality of reflux distributors 60 on the bottom of the reaction tank 10. The reflux distributor 60 can be installed on the bottom plate 11 of the reaction tank 10 through the third support 61, and the third support 61 is used for supporting the reflux distributor, so as to improve the position stability of the reflux distributor in the reaction tank 10.

[0063] Please refer to Figure 1 The plurality of water inlet distributors 40 are arranged on the same plane, the plurality of reflux distributors 60 are also arranged on the same plane, and the plane where the plurality of water inlet distributors 40 are arranged is parallel to the plane where the plurality of reflux distributors 60 are arranged. The reflux distributor 60 and the water inlet distributor 40 are arranged staggered, so as to realize the sufficient mass transfer of the wastewater and the reflux solution, that is, under the action of the liquid level, the ammonia nitrogen in the wastewater (the sludge in the wastewater contains anaerobic ammonia oxidation bacteria) and the nitrite in the reflux solution can be fully mixed, and the anaerobic reaction efficiency of the anaerobic reaction zone B can be improved.

[0064] In order to improve the reaction efficiency of the aerobic reaction zone A, please refer to Figure 1The wastewater anaerobic ammonia oxidation denitrification device further comprises a plurality of aerators 70. The plurality of aerators 70 are located in the reaction tank 10 and respectively communicate with the air inlet pipe 20. The aerators 70 can realize micro-bubbling of air to dissolve in the wastewater, increase the concentration of dissolved oxygen in the wastewater, and improve the reaction efficiency of the aerobic reaction zone A. Since the micro air bubbles output by the aerators 70 move to the top of the reaction tank 10 under the buoyancy of the wastewater, the reaction tank 10 can be divided into the aerobic reaction zone A located at the upper part of the reaction tank 10 and the anaerobic reaction zone B located at the lower part of the reaction tank 10. The aerators 70 are installed on the wall plate 12 of the reaction tank by a fourth support 71. The fourth support 71 is used to support the aerators 70 and improve the stability of the position of the aerators 70 in the reaction tank 10.

[0065] The sludge of the wastewater contains nitrosobacteria and nitrifying bacteria. In the aerobic reaction zone A, the ammonia nitrogen in the wastewater is converted into nitrite under the action of the nitrosobacteria. The generated nitrite is converted into nitrate under the action of the nitrifying bacteria. When the amount of dissolved oxygen in the wastewater in the aerobic reaction zone A is insufficient, the conversion of the nitrite into the nitrate under the action of the nitrifying bacteria is inhibited. The anaerobic zone needs the nitrite to be converted into nitrogen gas by the anaerobic ammonia oxidation bacteria. The stable operation of the anaerobic ammonia oxidation reaction needs the anaerobic ammonia oxidation bacteria and the nitrosobacteria to reach a proper bacterial population ratio. The anaerobic ammonia oxidation bacteria are anaerobic bacteria, and the nitrosobacteria are aerobic bacteria. Therefore, the concentration of dissolved oxygen in the aerobic reaction zone A needs to be controlled to control the progress of the anaerobic ammonia oxidation reaction.

[0066] Since the anaerobic zone needs the nitrite to be converted into nitrogen gas by the anaerobic ammonia oxidation bacteria, the generation amount of the nitrate in the aerobic reaction zone A needs to be inhibited, and the generation amount of the nitrite in the aerobic reaction zone A needs to be promoted. In order to inhibit the generation amount of the nitrate in the aerobic reaction zone A, the amount of dissolved oxygen in the wastewater needs to be accurately controlled. Therefore, the wastewater anaerobic ammonia oxidation denitrification device comprises a dissolved oxygen detector 80. The dissolved oxygen detector 80 is installed on the reaction tank 10 and located outside the reaction tank 10. The dissolved oxygen detector 80 communicates with a detection space in the reaction tank 10. The detection space is located between the aerators 70 and the top of the reaction tank 10. That is, the dissolved oxygen detector 80 can detect the dissolved oxygen of the wastewater in the aerobic reaction zone A. In order to ensure the accuracy of the dissolved oxygen detection value, the dissolved oxygen detector 80 needs to be calibrated regularly. The dissolved oxygen detector 80 can be connected to the reaction tank 10 through an instrument valve 81. When calibrated, the instrument valve 81 is closed, and the dissolved oxygen detector 80 is taken out from the instrument valve 81 for calibration.

[0067] The dissolved oxygen concentration in the aerobic reaction zone A is monitored by the dissolved oxygen detector 80. According to the detection value of the dissolved oxygen detector 80, the opening of the air inlet valve 21 is adjusted to keep the dissolved oxygen concentration in the aerobic reaction zone A within the control range. In this way, the amount of nitrite produced in the aerobic reaction zone A can be controlled by controlling the dissolved oxygen concentration in the wastewater, and the amount of N2 (nitrogen) produced in the anaerobic reaction zone B is promoted, thereby improving the nitrogen removal amount of the anaerobic ammonia oxidation reaction of the wastewater.

[0068] The aerobic reaction in the aerobic reaction zone A requires a specific concentration of dissolved oxygen. Air can be continuously blown into the air inlet pipe 20 to achieve sufficient contact between the micro-bubbles and the wastewater through the aerator 70 for the needs of the reaction bacteria in the aerobic reaction zone A. In order to make the bubbles in the aerobic reaction zone A completely converge in the gas guide cover 31, the gas guide cover 31 can be provided in multiple, and the multiple gas guide covers 31 are arranged in a matrix on the cross section of the reaction tank 10. The multiple gas guide covers 31 are arranged in layers along the vertical direction, and the multiple layers of gas guide covers 31 are staggered along the vertical direction and the edge parts overlap, so that the bubbles not collected by the lower layer of gas guide covers 31 can be collected by the upper layer of gas guide covers 31. Specifically, the multiple gas guide covers 31 can be provided in two layers, the gas guide covers 31 in the upper layer are installed on the wall plate 12 of the reaction tank through the upper layer of supports 312, and the upper layer of supports 312 are used to support the gas guide covers 31 to improve the position stability of the gas guide covers 31 in the reaction tank 10. The gas guide covers 31 in the lower layer are installed on the wall plate 12 of the reaction tank through the lower layer of supports 311, and the lower layer of supports 311 are used to support the gas guide covers 31 to improve the position stability of the gas guide covers 31 in the reaction tank 10.

[0069] In some embodiments, the gas guide cover 31 includes a cover body (not shown in the figure) and a gas guide pipe connected thereto. The cover body is in the shape of a horn, and the included angle between the cover body and the axis of the gas guide cover 31 can determine the diameter of the bubbles converged by the gas guide cover. The gas guide pipe is connected to the stripping pipe 32, and the diameter of the gas guide pipe is not less than the diameter of the stripping pipe 32. The included angle between the cover body and the axis of the gas guide cover 31 cooperates with the diameter of the stripping pipe 32, so that when the bubbles pass through the cover body, the gas guide pipe and the stripping pipe 32, they will carry the reaction solution (including and NH4 + , etc.) produced by the aerobic reaction to the gas release tank 34.

[0070] During the aerobic reaction, the anaerobic reaction and the process of the wastewater rising along with the liquid level in the reaction tank 10, the sludge in the wastewater will settle on the bottom plate 11 of the reaction tank 10. In order to facilitate the discharge of the sludge in the reaction tank 10, please refer to Figure 1 , the wall plate 12 of the reaction tank 10 is provided with a sludge discharge hole 14, and the sludge discharge hole 14 is close to the bottom plate 11. The sludge settled on the bottom plate 11 of the reaction tank 10 can be discharged through the sludge discharge hole 14. The sludge discharge hole 14 can be connected with a sludge discharge valve 15, when the amount of sludge in the reaction tank 10 increases beyond the normal amount, the sludge discharge valve 15 is opened, and the sludge is discharged through the sludge discharge valve 15.

[0071] In order to improve the separation efficiency of sludge and water in wastewater, please refer to Figure 1 , the separator 30 also includes a plurality of inclined plates 35 and a water outlet weir 36, the plurality of inclined plates 35 are installed on the outer side of the gas guide cover 31 away from the cover opening. The water outlet weir 36 is located above the gas guide cover 31, specifically, the water outlet weir 36 is installed on the inner side wall of the reaction tank 10 and close to the tank top of the reaction tank 10, the side wall of the reaction tank 10 is provided with a water outlet 16, and the water outlet 16 is communicated with the water outlet weir 36. The water outlet weir 36 is annular and surrounds the inner side plate of the reaction tank 10. Specifically, the water outlet weir 36 includes a ring-shaped supporting plate (not shown in the figure) and a ring-shaped vertical plate (not shown in the figure), the ring-shaped vertical plate is connected with the inner side wall of the wall plate 12 of the reaction tank 10 through the ring-shaped supporting plate, and the ring-shaped vertical plate is parallel to the wall plate, and the ring-shaped supporting plate is perpendicular to the ring-shaped vertical plate and the wall plate. The ring-shaped vertical plate and the ring-shaped supporting plate can prevent the input of clean water from bringing in silt, and improve the purity of clean water.

[0072] The gas guide cover 31 converges small bubbles to form large bubbles, and due to the buoyancy of the bubbles in the wastewater, the bubbles are transported to the gas release tank 34 through the stripping pipe 32. In the process of contacting the sludge-water mixture with the plurality of inclined plates 35, the sludge is attached to the surface of the plurality of inclined plates 35 under the action of gravity and the adsorption of activated sludge. The sludge attached to the surface of the plurality of inclined plates 35 falls to the bottom plate 11 of the reaction tank 10 under the action of gravity. Under the action of liquid level, the sludge falling to the bottom plate 11 of the reaction tank 10 is discharged from the sludge discharge valve 15. The clean water separated after flowing through the plurality of inclined plates 35 rises to the water outlet weir 36 and is discharged through the water outlet 16, realizing effective separation of sludge and water in wastewater.

[0073] The reaction principle and process of the wastewater anaerobic ammonia oxidation denitrification device in the present application:

[0074] The wastewater containing ammonia nitrogen to be treated enters the reactor from the liquid inlet 121, and the water inlet valve 51 is adjusted according to the wastewater treatment load in the reaction tank 10. The wastewater can be uniformly distributed at the bottom of the reaction tank 10 through the water inlet pipe 50 and the water distribution device 40. When the amount of sludge in the reaction tank 10 increases beyond the normal amount, the sludge discharge valve 15 is opened, and the sludge is discharged to the outside through the sludge discharge port.

[0075] The backflow solution is transported to the bottom of the reaction tank 10 through the backflow pipe 33, and can be fully mixed with the wastewater in the anaerobic reaction zone B, providing homogeneous substrate for anaerobic ammonia oxidation bacteria. Under the action of the liquid level of the wastewater and the backflow solution, the anaerobic ammonia oxidation bacteria in the sludge fully contact with the ammonia nitrogen in the wastewater, improving the denitrification reaction efficiency of the anaerobic reaction zone B.

[0076] In the anaerobic reaction zone B, the anaerobic ammonia oxidation bacteria convert ammonia nitrogen and nitrite into nitrogen gas, and the stoichiometric equation of the denitrification reaction is as follows:

[0077]

[0078] After the wastewater and the reflux solution pass through the anaerobic reaction zone B, they are lifted by the liquid level into the aerobic reaction zone A. The aerobic reaction in the aerobic reaction zone A requires a specific concentration of dissolved oxygen. Air is continuously blown into the air inlet pipe 20, and the air is broken into small bubbles by the aerator 70 to provide sufficient contact between the air and the wastewater for the aerobic reaction in the aerobic reaction zone A. The dissolved oxygen concentration in the aerobic reaction zone A is monitored by the dissolved oxygen detector 80. According to the value detected by the dissolved oxygen detector 80, the opening of the air inlet valve 21 is adjusted to keep the dissolved oxygen concentration in the aerobic reaction zone A within a controlled range.

[0079] In the aerobic reaction zone A, the ammonia nitrogen is converted into nitrite by the nitrosation bacteria, and the reaction stoichiometric equation is as follows:

[0080]

[0081] After the sludge-water mixture passes through the aerobic reaction zone A, it is lifted by the liquid level into the first separation zone. The first separation zone includes the air guide cover 31 and the multi-layer inclined plate 35. The air guide cover 31 gathers the small bubbles to form large bubbles, and the bubbles are transported to the second separation zone due to the buoyancy of the bubbles in the wastewater. The sludge-water mixture is in contact with the multi-layer inclined plate 35, and the sludge is attached to the surface of the multi-layer inclined plate 35 due to the gravity and the adsorption of the activated sludge. The clear water separated by flowing through the multi-layer inclined plate 35 is lifted to the water outlet weir 36 and is discharged through the water outlet 16, thereby effectively separating the sludge and the water in the wastewater.

[0082] The second separation zone includes the stripping pipe 32, the gas release tank 34, and the reflux pipe 33.

[0083] The bubbles are transported to the second separation zone through the stripping pipe 32. Since the diameter of the stripping pipe 32 is small and the diameter of the bubbles in the air guide cover 31 is large, the bubbles will carry the reaction solution (including the NO2-, and NH4 + , etc.) produced by the aerobic reaction when the bubbles pass through the stripping pipe 32 and are transported to the gas release tank 34. Since the internal space of the gas release tank 34 is large, the pressure of the bubbles is reduced when the bubbles pass through the stripping pipe 32 and are transported into the gas release tank 34, and the gas in the bubbles is released and discharged from the gas outlet 342. The gas discharged from the gas outlet 342 includes carbon dioxide, nitrogen, and a small amount of oxygen, etc., and the gas can be released into the atmosphere.

[0084] According to the position of the gas inlet pipe 20 in the vertical direction in the reaction tank 10, the reaction tank 10 can be divided into an aerobic reaction zone A and an anaerobic reaction zone B, and the aerobic reaction zone A is located above the anaerobic reaction zone B. In this way, the aerobic reaction zone A, the anaerobic reaction zone B and the separator 30 can be integrated in the reaction tank 10, reducing the land area occupied by the wastewater anaerobic ammonia oxidation denitrification device, and also improving the efficiency of wastewater anaerobic ammonia oxidation denitrification. Controlling the aerobic reaction and the anaerobic reaction in the reaction tank 10 respectively can improve the reaction efficiency and improve the denitrification efficiency.

[0085] The total nitrogen load of the conventional denitrification process is generally 0.15kgTN / (m 3 ·d) to 0.20kgTN / (m 3 ·d), and the total nitrogen load of the denitrification process in the present application can reach more than 1.0kgTN / (m 3 ·d), that is, under the same wastewater influent water quality conditions, the volume of the reaction tank 10 is 1 / 5 to 1 / 6 of that of the conventional denitrification reaction tank 10, to a certain extent, reducing the land area occupied by the wastewater anaerobic ammonia oxidation denitrification device.

[0086] In the one-stage anaerobic ammonia oxidation device in the related art, the aerobic reaction and the anaerobic reaction are carried out in the same area. The total nitrogen load of the one-stage anaerobic ammonia oxidation device is generally 0.5kgTN / (m 3 ·d), and the denitrification efficiency is low. In the present application, the aerobic reaction zone A and the anaerobic reaction zone B are arranged in different areas in the vertical direction, and the total nitrogen load can reach more than 1.0kgTN / (m 3 ·d), improving the reaction efficiency and improving the denitrification efficiency.

[0087] The conventional denitrification process uses an anoxic tank, an aerobic tank, a secondary sedimentation tank and a corresponding sludge return device, and has a large land area. In the present application, the reaction tank 10 can be divided into an aerobic reaction zone A and an anaerobic reaction zone B, and the aerobic reaction zone A is located above the anaerobic reaction zone B. In this way, the aerobic reaction zone A, the anaerobic reaction zone B and the separator 30 can be integrated in the reaction tank 10, reducing the land area occupied by the wastewater anaerobic ammonia oxidation denitrification device, and the land area is 1 / 10 to 1 / 12 of that of the conventional denitrification process.

[0088] In the present application, unless specifically defined and limited otherwise, the "on" or "under" of a first feature to a second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the "on", "above" and "under" of the first feature to the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the first feature is higher in horizontal height than the second feature. The "under", "below" and "under" of the first feature to the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the first feature is lower in horizontal height than the second feature.

[0089] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" indicate the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0090] In the present application, unless otherwise specifically defined and limited, the terms "connection", "fixing" and the like should be broadly understood, for example, "fixing" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection; can be directly connected, or indirectly connected through intermediate medium, can be internal connection of two elements or interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0091] In addition, the description of "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implying the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically defined.

[0092] Although the embodiments of the present application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and purposes of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A wastewater anammox denitrification method, characterized by, The application discloses an anaerobic ammonia oxidation denitrification device for wastewater, which comprises the following parts: a reaction tank, which is provided with a liquid inlet close to the tank bottom of the reaction tank; an air inlet pipe, which is installed in the reaction tank, and the air outlet of the air inlet pipe is located in the middle of the reaction tank, and the air inlet pipe is provided with an air inlet valve for adjusting the flow in the air inlet pipe; a separator, which is installed on the tank top of the reaction tank and comprises a gas guide cover, a stripping pipe, a reflux pipe and a gas release tank, the cover opening of the gas guide cover faces downward, one end of the stripping pipe is communicated with the gas guide cover, the other end of the stripping pipe is communicated with the gas release tank, the tank top of the gas release tank is provided with an exhaust port, one end of the reflux pipe is communicated with the gas release tank, the other end of the reflux pipe penetrates through the tank top of the reaction tank and extends to the lower part of the air inlet pipe; a plurality of aerators, which are communicated with the air inlet pipe and located in the reaction tank; a dissolved oxygen detector, which is installed on the reaction tank and located outside the reaction tank, the dissolved oxygen detector is communicated with a detection space in the reaction tank, and the detection space is located between the aerators and the tank top of the reaction tank; wherein the chamber in the reaction tank is divided into an aerobic reaction zone between the separator and the air inlet pipe and an anaerobic reaction zone between the air inlet pipe and the tank bottom of the reaction tank; the anaerobic ammonia oxidation denitrification method for wastewater comprises the following steps: The wastewater containing anaerobic ammonia nitrogen to be treated continuously enters the anaerobic reaction zone of the reaction tank from the liquid inlet, as the liquid level in the reaction tank rises, the liquid surface of the wastewater gradually submerges the gas inlet pipe and rises to the aerobic reaction zone, the sludge of the wastewater contains nitrosobacteria, the air continuously delivered by the gas inlet pipe is dissolved in the wastewater, providing an aerobic environment for the reaction of the nitrosobacteria in the wastewater, the nitrosobacteria convert the anaerobic ammonia nitrogen in the aerobic reaction zone into nitrite, the reaction stoichiometric formula is ; with the increase of the liquid level in the reaction tank, the bubbles of the dissolved air which do not participate in the oxidation reaction in the wastewater in the air inlet pipe gather in the gas guide cover, when the bubbles are transported into the gas release tank through the stripping pipe, the pressure of the bubbles is reduced, the bubbles are broken, the gas in the bubbles is released and discharged from the exhaust port, since the gas guide cover is immersed in the wastewater, the wastewater in the aerobic reaction zone moves to the gas release tank along the stripping pipe, the reaction solution is gathered at the bottom of the gas release tank under the action of gravity and moves to the anaerobic reaction zone of the reaction tank along the reflux pipe to participate in the anaerobic reaction, so that the separation of the gas and the reaction solution is realized; The reflux solution is transported through the reflux pipe to the tank bottom of the reaction tank, and the reflux solution is mixed with the wastewater in the anaerobic reaction zone, and the sludge in the wastewater in the anaerobic reaction zone contains anaerobic ammonia oxidation bacteria, and under an anaerobic environment, ammonia nitrogen and nitrite are converted into nitrogen by the action of anaerobic ammonia oxidation bacteria, and the stoichiometric equation of the denitrification reaction is ; the liquid inlet of the reaction tank continuously inputs the wastewater, N2 generated by the anaerobic reaction is dissolved in the wastewater and forms nitrogen bubbles, with the increase of the liquid level in the reaction tank, the wastewater gradually rises to the aerobic reaction zone, the nitrogen bubbles gather in the gas guide cover and are transported to the gas release tank through the stripping pipe, and the nitrogen is discharged from the exhaust port of the gas release tank; according to the detection data of the dissolved oxygen detector, the air inlet valve is controlled, so that the concentration of the dissolved oxygen in the aerobic reaction zone is within the control range, and the generation amount of nitrate in the aerobic reaction zone is inhibited.

2. The wastewater anammox denitrification process of claim 1, wherein, the anaerobic ammonia oxidation denitrification device for wastewater further comprises: a plurality of water inlet distributors, which are uniformly distributed in the reaction tank; a water inlet pipe, which is provided with a same number of water outlets as the water inlet distributors, the water outlets are located in the reaction tank, the water outlets of the water inlet pipe are communicated with the water inlet distributors one by one, the water inlet pipe penetrates through the liquid inlet, and the water inlet of the water inlet pipe is located outside the reaction tank.

3. The wastewater anammox denitrification process of claim 2, wherein, the anaerobic ammonia oxidation denitrification device for wastewater further comprises: A plurality of backflow water distributors are located in the reaction tank and are communicated with the end of the backflow pipe away from the gas release tank, and the outlet of the backflow water distributor faces the water inlet distributor.

4. The wastewater anammox denitrification method according to claim 3, characterized by, The water inlet distributor and the backflow water distributor are staggered.

5. The wastewater anaerobic ammonium oxidation denitrification method according to any one of claims 1 to 4, characterized in that: The gas guide cover is provided with a plurality of gas guide covers arranged in a matrix in the cross section of the reaction tank.

6. The wastewater anammox denitrification method according to claim 5, characterized in that, The separator further comprises: A plurality of inclined plates are installed on the outer side of the gas guide cover away from the cover opening. A water outlet weir is located above the gas guide cover and is installed on the inner side wall of the reaction tank close to the tank top of the reaction tank.

7. The wastewater anammox denitrification process of claim 6, wherein, The water outlet weir is annular and is installed on the inner side wall of the reaction tank around the axis of the reaction tank.

8. The method according to any one of claims 1 to 4, wherein the wastewater anammox denitrification is performed at a temperature of 25 to 60°C, preferably 30 to 50°C, more preferably 35 to 45°C. The reaction tank is provided with a sludge discharge hole near the bottom.

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