Methylamine wastewater denitrification system and method based on partial nitrification-anaerobic ammonia oxidation

Abstract

The invention provides a methylamine wastewater denitrification system and method based on partial nitrification-anaerobic ammonia oxidation. The methylamine wastewater denitrification system comprises a sequencing batch partial nitrification reaction device, an adjusting device and an expanded granular sludge bed anaerobic ammonia oxidation reaction device, the sequencing batch partial nitration reaction device and the expanded granular sludge bed anaerobic ammonia oxidation reaction device are respectively communicated with the adjusting device; the sequencing batch type partial nitration reaction device is used for carrying out nitration reaction on wastewater and strains, controlling the aeration intensity and the aeration time in the sequencing batch type partial nitration reaction device, and adjusting the concentration of dissolved oxygen in the sequencing batch type partial nitration reaction device to regulate and control the progress of the nitration reaction; the adjusting device is used for detecting and monitoring the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater in the sequencing batch partial nitration reaction device, so that the wastewater with the ratio reaching a preset value is injected into the expanded granular sludge bed anaerobic ammonia oxidation reaction device; the expanded granular sludge bed anaerobic ammonia oxidation reaction device is used for carrying out anaerobic ammonia oxidation reaction treatment on the wastewater reaching a preset value and discharging purified water.

Description

Technical Field

[0001] This application relates to the technical field of wastewater treatment, and in particular, to a denitrification system and method for methylamine wastewater based on partial nitrification - anaerobic ammonium oxidation. Background Art

[0002] During the production of methylamine, a large amount of methylamine wastewater is generated, which contains more polluting ammonia nitrogen and organic nitrogen compounds. Since nitrogen pollution is one of the main factors leading to water eutrophication, starting from protecting water resources and natural resources, methylamine wastewater must be denitrified and treated to meet the standards before being discharged.

[0003] For the treatment of nitrogen - containing wastewater, the more common one is the traditional nitrification - denitrification denitrification technology. However, in the actual application process, it often has the disadvantages of large aeration energy consumption, the need to add additional carbon sources, and a large amount of excess sludge. Summary of the Invention

[0004] This application provides a denitrification system and method for methylamine wastewater based on partial nitrification - anaerobic ammonium oxidation, so as to solve the technical problems of large denitrification aeration volume, high cost of additional carbon source addition, and large amount of sludge in the prior art.

[0005] In a first aspect, this application provides a denitrification system for methylamine wastewater based on partial nitrification - anaerobic ammonium oxidation, including: a sequencing batch partial nitrification reaction device, a regulating device, and an expanded granular sludge bed anaerobic ammonium oxidation reaction device;

[0006] The sequencing batch partial nitrification reaction device and the expanded granular sludge bed anaerobic ammonium oxidation reaction device are respectively connected to the regulating device through a plurality of pipelines;

[0007] The sequencing batch partial nitrification reaction device is used for the nitrification reaction of wastewater and bacteria, and controls the aeration intensity and / or aeration time in the sequencing batch partial nitrification reaction device, adjusts the dissolved oxygen concentration in the sequencing batch partial nitrification reaction device, and regulates the process of the nitrification reaction;

[0008] The regulating device is used to detect and monitor the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater in the sequencing batch partial nitrification reaction device, and inject the wastewater with the ratio reaching a predetermined value into the expanded granular sludge bed anaerobic ammonium oxidation reaction device;

[0009] The expanded granular sludge bed anaerobic ammonium oxidation reaction device is used to perform anaerobic ammonium oxidation reaction treatment on the wastewater reaching the preset value and discharge the treated purified water.

[0010] In a possible implementation manner, the sequencing batch partial nitrification reaction device includes an aerator;

[0011] The aerator communicates with the bottom end of the sequencing batch partial nitrification reaction device. The aerator is used to control the aeration intensity and / or aeration time, adjust the dissolved oxygen concentration in the sequencing batch partial nitrification reaction device, and regulate the process of the nitrification reaction.

[0012] In a possible implementation manner, a filtering device is arranged in the sequencing batch partial nitrification reaction device, and the filtering device communicates with the regulating device;

[0013] The filtering device is used to filter the wastewater flowing from the sequencing batch partial nitrification reaction device into the regulating device.

[0014] In a possible implementation manner, a three-phase separator is arranged on the expanded granular sludge bed anaerobic ammonium oxidation reaction device;

[0015] The three-phase separator is arranged at the top end of the expanded granular sludge bed anaerobic ammonium oxidation reaction device, and the three-phase separator communicates with the expanded granular sludge bed anaerobic ammonium oxidation reaction device;

[0016] The three-phase separator is used to discharge the purified water and / or gas generated after the anaerobic ammonium oxidation reaction in the expanded granular sludge bed anaerobic ammonium oxidation reaction device to the outside of the expanded granular sludge bed anaerobic ammonium oxidation reaction device.

[0017] In a possible implementation manner, a constant temperature device is further included. The constant temperature device communicates with the sequencing batch partial nitrification reaction device and the expanded granular sludge bed anaerobic ammonium oxidation reaction device respectively through the plurality of pipelines;

[0018] The constant temperature device is used to adjust the temperature in the sequencing batch partial nitrification reaction device and the expanded granular sludge bed anaerobic ammonium oxidation reaction device to any temperature value, and control the temperature to be maintained at the temperature value.

[0019] In a possible implementation manner, a water inlet device and a plurality of stirring devices are further included;

[0020] The water inlet device communicates with the sequencing batch partial nitrification reaction device, and the water inlet device is used to store the wastewater to be treated;

[0021] The plurality of stirring devices are respectively arranged in the water inlet device, the sequencing batch partial nitrification reaction device, and the regulating device; the plurality of stirring devices are used for stirring.

[0022] In a possible implementation manner, a plurality of electric pumps are further included;

[0023] At least one electric pump is correspondingly arranged on each of the pipelines.

[0024] Second aspect, the present application provides a method for denitrifying methylamine wastewater based on partial nitrification-anaerobic ammonium oxidation, adopting any possible implementation manner of the first aspect of the present application, including the following steps:

[0025] Inject the wastewater to be treated into the sequencing batch partial nitrification reaction device, add strains, and control the aeration time and / or aeration intensity to carry out nitrification reaction;

[0026] After the nitrification reaction is completed, the wastewater is injected from the sequencing batch partial nitrification reaction device into the adjustment device, and it is detected whether the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater reaches the predetermined value;

[0027] Inject the wastewater that reaches the predetermined value from the adjustment device into the expanded granular sludge bed anaerobic ammonium oxidation reaction device for anaerobic ammonium oxidation denitrification treatment, and discharge the treated purified water.

[0028] In a possible implementation manner, the detection of whether the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater reaches the predetermined value includes:

[0029] If so, inject the wastewater from the adjustment device into the expanded granular sludge bed anaerobic ammonium oxidation reaction device;

[0030] If not, inject the wastewater from the adjustment device into the sequencing batch partial nitrification reaction device, and control the aeration time and / or aeration intensity to adjust the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater.

[0031] In a possible implementation manner, the ratio of nitrite nitrogen to ammonia nitrogen in the predetermined value is 0.8 to 1.8;

[0032] And / or, the aeration intensity is 0.05 to 0.5 L / min;

[0033] And / or, the aeration time is 5 to 60 min.

[0034] A denitrification system and method for methylamine wastewater based on partial nitrification-anammox provided by the present application, which comprises a sequencing batch partial nitrification reaction device, a regulating device and an expanded granular sludge bed anammox reaction device; the sequencing batch partial nitrification reaction device and the expanded granular sludge bed anammox reaction device are respectively connected to the regulating device through a plurality of pipelines; the sequencing batch partial nitrification reaction device is used for carrying out nitrification reaction on wastewater and strains, and controlling the aeration intensity and / or aeration time in the sequencing batch partial nitrification reaction device, adjusting the dissolved oxygen concentration in the sequencing batch partial nitrification reaction device, and regulating the process of nitrification reaction; the regulating device is used for detecting and monitoring the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater in the sequencing batch partial nitrification reaction device, and injecting the wastewater with the ratio reaching a predetermined value into the expanded granular sludge bed anammox reaction device; the expanded granular sludge bed anammox reaction device is used for carrying out anammox reaction treatment on the wastewater reaching the preset value, and discharging the treated purified water. In specific implementation, the methylamine wastewater is introduced into the sequencing batch partial nitrification reaction device, and a certain amount of strains are added to carry out partial nitrification reaction. The regulating device detects and monitors whether the ratio of nitrite nitrogen to ammonia nitrogen in the sequencing batch partial nitrification reaction device reaches a predetermined value. The regulating device can control the aeration volume of the sequencing batch partial nitrification reaction device, thereby preventing excessive aeration and reducing energy consumption; for the wastewater reaching the predetermined value, it is introduced into the expanded granular sludge bed anammox reaction device to carry out anammox reaction, and the generated nitrogen and purified water are discharged, which can reduce the generation of sludge, and only nitrogen is generated in the expanded granular sludge bed anammox reaction device, without the emission of greenhouse gases such as nitrous oxide, which better protects the environment. The system provided by the embodiment of the present application has small denitrification aeration volume, saves energy consumption, does not require additional carbon source addition, has low cost, and has small sludge generation amount. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0036] Figure 1 It is a schematic structural diagram of a denitrification system for methylamine wastewater based on partial nitrification-anammox provided by an embodiment of the present application;

[0037] Figure 2 It is a process flow diagram of a denitrification method for methylamine wastewater based on partial nitrification-anammox provided by an embodiment of the present application;

[0038] Figure 3 It is provided by an embodiment of the present application and uses Figure 1 in the system or Figure 2 in the method, a partial nitrification performance line graph;

[0039] Figure 4 It is provided by an embodiment of the present application and usesFigure 1 In the system or Figure 2 Line graph of the anaerobic ammonium oxidation denitrification performance of the method in;

[0040] Figure 5 Provided by an embodiment of the present application using Figure 1 In the system or Figure 2 Bar graph of the anaerobic ammonium oxidation activity of the microorganisms in the method in;

[0041] Figure 6 Provided by an embodiment of the present application using Figure 1 In the system or Figure 2 Bar graph of the sludge sedimentation performance of the method in Figure 1 ;

[0042] Figure 7 Provided by an embodiment of the present application using Figure 1 In the system or Figure 2 Bar graph of the sludge sedimentation performance of the method in Figure 2 .

[0043] Explanation of reference numerals:

[0044] 10 - Inlet device;

[0045] 20 - Sequencing batch partial nitrification reactor;

[0046] 21 - Aerator;

[0047] 22 - Filter device;

[0048] 30 - Adjusting device;

[0049] 40 - Expanded granular sludge bed anaerobic ammonium oxidation reactor;

[0050] 41 - Three-phase separator;

[0051] 50 - Constant temperature device;

[0052] 60 - Stirring device;

[0053] 70 - Electric pump;

[0054] 80 - Pipeline.

[0055] Through the above-mentioned drawings, specific embodiments of the present application have been shown, and there will be more detailed descriptions hereinafter. These drawings and written descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. Detailed implementation manners

[0056] Exemplary embodiments will be described in detail herein, and examples thereof are shown in the accompanying drawings. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0057] Methylamine wastewater is the wastewater generated during the production of methylamine. It is large in scale, wide in scope, and highly polluting. It contains a relatively large amount of ammonia nitrogen and organic nitrogen compounds, and is a type of wastewater with a relatively large amount of nitrogen pollution. Nitrogen pollution, as an important pollution index in China, is one of the main factors leading to water eutrophication. Starting from protecting water resources and natural resources, methylamine wastewater must be denitrified and treated to meet the standards before it can be discharged.

[0058] In traditional methylamine wastewater treatment, the removal of nitrogen-containing pollutants mainly relies on nitrification and denitrification technologies, but there are many drawbacks such as the need for external carbon sources and high energy consumption.

[0059] For the treatment of nitrogen-containing wastewater, biological denitrification methods have become the main technologies for wastewater denitrification due to their stable treatment effect, simple operation, no secondary pollution, economic efficiency, etc. Among them, the more common ones are mainly traditional nitrification-denitrification technologies. However, in the actual application process, it often has the deficiencies of large aeration energy consumption, the need for additional carbon source addition, and a large amount of excess sludge. For the denitrification treatment of wastewater, it is urgent to explore more low-carbon, energy-saving, and low-cost technologies.

[0060] Anaerobic ammonium oxidation (Anammox) is a special biological denitrification process. Under anaerobic conditions, ammonia nitrogen and nitrite nitrogen can be converted into nitrogen gas in a certain proportion. The popularization of its engineering application will strongly promote the implementation of the concept of sustainable development in China. Methylamine wastewater often needs to pass through an organic matter removal unit first, and then subsequent denitrification. The anaerobic digestion liquid after anaerobic digestion contains a large amount of ammonia nitrogen, and the carbon-nitrogen ratio is theoretically compatible with the Anammox technology. Therefore, the Anammox technology is very suitable for the denitrification of methylamine wastewater. However, it needs to be combined with a suitable pre-nitrification process to achieve smooth denitrification. Therefore, it is very important to develop an effective Anammox denitrification system, and the denitrification performance of this system for actual methylamine wastewater also needs to be investigated.

[0061] A methylamine wastewater denitrification system and method based on partial nitrification-Anammox provided by the present application aims to solve the technical problems of large denitrification aeration volume, high cost of additional carbon source addition, and large amount of sludge in the prior art.

[0062] The technical solution of the present application and how the technical solution of the present application solves the above technical problems will be described in detail below with specific embodiments. The following several specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in some embodiments. The embodiments of the present application will be described below with reference to the accompanying drawings.

[0063] Figure 1 It is a schematic structural diagram of a methylamine wastewater denitrification system based on partial nitrification - anammox provided by an embodiment of the present application; (PN - Partial nitrification: the process of oxidizing NH 4 + -N to NO 2 - -N; AMX - Anammox; Anaerobic ammonium oxidation: anaerobic ammonium oxidation; P: Pump, peristaltic pump; A: Air, aeration pump). As Figure 1 shown, the system includes: a sequencing batch partial nitrification reaction device 20, a regulating device 30, and an expanded granular sludge bed anaerobic ammonium oxidation reaction device 40; the sequencing batch partial nitrification reaction device 20 and the expanded granular sludge bed anaerobic ammonium oxidation reaction device 40 are respectively connected to the regulating device 30 through a plurality of pipelines 80; the sequencing batch partial nitrification reaction device 20 is used for the nitrification reaction of wastewater and bacteria, and controls the aeration intensity and / or aeration time in the sequencing batch partial nitrification reaction device 20, adjusts the dissolved oxygen concentration in the sequencing batch partial nitrification reaction device 20, and regulates the progress of the nitrification reaction; the regulating device 30 is used to detect and monitor the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater in the sequencing batch partial nitrification reaction device 20, and inject the wastewater with the ratio reaching a predetermined value into the expanded granular sludge bed anaerobic ammonium oxidation reaction device 40; the expanded granular sludge bed anaerobic ammonium oxidation reaction device 40 is used for anaerobic ammonium oxidation reaction treatment of the wastewater reaching the preset value, and discharges the treated purified water.

[0064] The sequencing batch partial nitrification reaction device 20 is mainly used to complete the nitrification reaction process of methylamine wastewater. The methylamine wastewater is injected into the sequencing batch partial nitrification reaction device 20, and bacteria participating in the reaction, such as AOB bacteria and / or NOB bacteria, etc., are added to react with the methylamine wastewater in the reaction device 20 for partial nitrification reaction. Among them, ammonia - oxidizing bacteria (AOB bacteria) are an important class of autotrophic nitrifying microorganisms, mainly participating in the ammonia oxidation process in soil and water bodies. They play a key role in the nitrogen cycle and can convert ammonia nitrogen into nitrite, and then participate in nitrification. Nitrite - oxidizing bacteria (NOB) are a class of bacteria that can oxidize nitrite (NO 2 - ) into nitrate (NO 3- ) bacteria. This process is part of nitrification, an important step in the nitrogen cycle. Nitrite-oxidizing bacteria usually work in concert with ammonia-oxidizing bacteria (AOB), which oxidize ammonia (NH 3 ) to nitrite.

[0065] To control the nitrification reaction in the sequencing batch partial nitrification reaction device 20, a certain amount of aeration is required to adjust the dissolved oxygen concentration in the reaction device 20, allowing oxygen to participate in the nitrification reaction and thus controlling the process of partial nitrification. The sequencing batch partial nitrification reaction device 20 can also control the aeration intensity and aeration time in the device, enabling partial nitrification rather than complete nitrification in the sequencing batch partial nitrification reaction device 20, thereby reducing energy consumption.

[0066] Since bacteria are used for the reaction, the sequencing batch partial nitrification reaction device 20 needs to be maintained at a specific temperature. Therefore, the sequencing batch partial nitrification reaction device 20 is made of heat-insulating, anti-corrosive, and wear-resistant materials. The sequencing batch partial nitrification reaction device 20, the regulating device 30, and the expanded granular sludge bed anaerobic ammonium oxidation reaction device 40 are interconnected through multiple pipes 80. The multiple pipes 80 not only use anti-corrosive materials to ensure that they are not eroded by chemical substances during the treatment process but also use wear-resistant materials to resist the wear of the inner wall of the pipes by particulate matter. In addition, the pipes 80 also have heat-insulating properties, which can effectively maintain the temperature stability of the fluid during transmission, ensuring the efficient operation and energy utilization of the entire system.

[0067] The regulating device 30 is used to detect and monitor the nitrification process in the sequencing batch partial nitrification reaction device 20 in real time, control the ratio of nitrite nitrogen to ammonia nitrogen in the reaction products obtained in the sequencing batch partial nitrification reaction device 20, enable partial nitrification to be completed in the sequencing batch partial nitrification reaction device 20, and thus control the aeration intensity and aeration time in the sequencing batch partial nitrification reaction device 20, which can reduce the aeration volume. Compared with the aeration volume used for complete nitrification in the prior art, it is smaller, reducing energy consumption. And the regulating device 30 can monitor whether the ratio of nitrite nitrogen to ammonia nitrogen in the sequencing batch partial nitrification reaction device 20 reaches a predetermined value. For the wastewater that reaches the predetermined value, it is introduced into the expanded granular sludge bed anaerobic ammonium oxidation reaction device 40 for anaerobic ammonium oxidation reaction; while for the wastewater that does not reach the predetermined value, it can be introduced into the sequencing batch partial nitrification reaction device 20, and the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater can be adjusted by adjusting the aeration parameters (such as aeration time, aeration intensity, etc.).

[0068] The expanded granular sludge bed anaerobic ammonium oxidation reaction device 40 is specifically used to perform the anaerobic ammonium oxidation reaction, and its core function is to treat the wastewater from the sequencing batch partial nitrification reaction device 20 or the regulating device 30. In these front-end devices, the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater is adjusted to a predetermined value to achieve the best reaction efficiency in the expanded granular sludge bed anaerobic ammonium oxidation reaction device 40.

[0069] In the expanded granular sludge bed anaerobic ammonium oxidation reaction device 40, the wastewater is purified through an autotrophic denitrification process, which does not require the additional addition of an external carbon source, thereby reducing the operating cost and complexity. In addition, the sludge growth rate in this device is relatively slow, resulting in an extremely low sludge yield. This characteristic significantly reduces the subsequent treatment and disposal costs of the sludge, improving the economy and sustainability of the entire system. Moreover, there is a small amount of organic matter in the expanded granular sludge bed anaerobic ammonium oxidation reaction device 40, which helps the remaining nitrate nitrogen to be denitrified, thereby achieving deep nitrogen removal.

[0070] In the specific implementation process, the methylamine wastewater is introduced into the sequencing batch partial nitrification reaction device 20, and a certain amount of bacteria is added to carry out the partial nitrification reaction. The regulating device 30 detects and monitors whether the ratio of nitrite nitrogen to ammonia nitrogen in the sequencing batch partial nitrification reaction device 20 reaches the predetermined value. For the wastewater that reaches the predetermined value, it is introduced into the expanded granular sludge bed anaerobic ammonium oxidation reaction device 40 to carry out the anaerobic ammonium oxidation reaction. The generated nitrogen and purified water are discharged, and only nitrogen is generated in the expanded granular sludge bed anaerobic ammonium oxidation reaction device 40, without the emission of greenhouse gases such as nitrous oxide, which better protects the environment.

[0071] The embodiment of the present application provides a methylamine wastewater denitrification system based on partial nitrification-anaerobic ammonium oxidation, which includes a sequencing batch partial nitrification reaction device, a regulating device, and an expanded granular sludge bed anaerobic ammonium oxidation reaction device; the sequencing batch partial nitrification reaction device and the expanded granular sludge bed anaerobic ammonium oxidation reaction device are respectively connected to the regulating device through a plurality of pipelines; the sequencing batch partial nitrification reaction device is used for the wastewater and bacteria to carry out the nitrification reaction, and controls the aeration intensity and / or aeration time in the sequencing batch partial nitrification reaction device, adjusts the dissolved oxygen concentration in the sequencing batch partial nitrification reaction device, and regulates the process of the nitrification reaction; the regulating device is used to detect and monitor the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater in the sequencing batch partial nitrification reaction device, and inject the wastewater with the ratio reaching the predetermined value into the expanded granular sludge bed anaerobic ammonium oxidation reaction device; the expanded granular sludge bed anaerobic ammonium oxidation reaction device is used to carry out the anaerobic ammonium oxidation reaction treatment on the wastewater that reaches the preset value, and discharge the treated purified water. The system provided by the embodiment of the present application has a small denitrification aeration volume, saves energy consumption, does not require additional carbon source addition, has a low cost, and has a small sludge production.

[0072] Further, on the basis of the above embodiment, refer toFigure 1 , The sequencing batch partial nitrification reaction device 20 includes an aerator 21; the aerator 21 is communicated with the bottom end of the sequencing batch partial nitrification reaction device 20, and the aerator 21 is used to control the aeration intensity and / or aeration time, adjust the dissolved oxygen concentration in the sequencing batch partial nitrification reaction device 20, and regulate the process of the nitrification reaction.

[0073] The aerator 21 is directly communicated with the bottom end of the sequencing batch partial nitrification reaction device 20 to ensure that the gas can be evenly distributed throughout the reactor. The aerator 21 is used to control the aeration intensity and / or aeration time, thereby effectively adjusting the dissolved oxygen concentration in the reaction device. By precisely controlling the dissolved oxygen concentration, the aerator 21 can directly affect the process of the nitrification reaction. Specifically, an appropriate dissolved oxygen level helps to optimize the activity of ammonia-oxidizing bacteria, thereby increasing the production efficiency of nitrite. This control not only improves the efficiency of the reaction but also prevents over-nitrification and avoids unnecessary nitrate production. In addition, the aerator 21 enables it to make dynamic adjustments according to changes in the influent water quality, ensuring that the reactor can maintain optimal performance under different operating conditions, which not only improves the stability and reliability of the system but also reduces energy consumption and further enhances the economic benefits and environmental friendliness of the entire sequencing batch partial nitrification reaction device 20.

[0074] Furthermore, as Figure 1 shown, a filtering device 22 is provided inside the sequencing batch partial nitrification reaction device 20, and the filtering device 22 is communicated with the regulating device 30; the filtering device 22 is used to filter the wastewater flowing from the sequencing batch partial nitrification reaction device 20 into the regulating device 30.

[0075] The filtering device 22 is arranged inside the sequencing batch partial nitrification reaction device 20 and is communicated with the regulating device 30 to form an efficient filtering and transmission system for treating the flocs or particulate matters contained in the sequencing batch partial nitrification reaction device 20. During the wastewater treatment process, these flocs or particulate matters may affect the efficiency and effect of subsequent treatment steps. The filtering device 22 removes suspended solids and particulate impurities in the wastewater through physical interception and separation, ensuring the water quality flowing into the regulating device 30, which not only helps to protect the normal operation of the regulating device 30 and prevent it from being blocked or worn due to particulate matter accumulation but also improves the overall efficiency of the entire treatment system.

[0076] The filtering device 22 can also be easily maintained and cleaned to ensure its efficient filtering ability during long-term operation, enabling the sequencing batch partial nitrification reaction device 20 to better adapt to different water quality conditions and enhancing the reliability and sustainability of the entire wastewater treatment process.

[0077] Furthermore, as Figure 1As shown in the figure, a three-phase separator 41 is provided on the anaerobic ammonium oxidation reaction device 40 with an expanded granular sludge bed; the three-phase separator 41 is arranged at the top of the anaerobic ammonium oxidation reaction device 40 with an expanded granular sludge bed, and the three-phase separator 41 is communicated with the anaerobic ammonium oxidation reaction device 40 with an expanded granular sludge bed; the three-phase separator 41 is used to discharge the purified water and / or gas generated after the anaerobic ammonium oxidation reaction in the anaerobic ammonium oxidation reaction device 40 with an expanded granular sludge bed to the outside of the anaerobic ammonium oxidation reaction device 40 with an expanded granular sludge bed.

[0078] The three-phase separator 41 is arranged at the top of the reaction device 40 and is directly communicated with the anaerobic ammonium oxidation reaction device 40 with an expanded granular sludge bed to form an efficient separation and discharge system. The three-phase separator 41 is used to effectively separate different-phase substances generated during the reaction process. Specifically, it can separate the purified water and gas generated after the anaerobic ammonium oxidation reaction from the reaction device and discharge them to the outside of the device 41. And the three-phase separator 41 ensures that the purified water can be discharged smoothly, reduces the hydraulic retention time in the system, and improves the treatment efficiency. At the same time, the three-phase separator 41 can also effectively discharge the gas generated during the reaction process, preventing the gas from accumulating in the system and affecting the normal operation of the reactor and the stability of the granular sludge.

[0079] Furthermore, as Figure 1 shown in the figure, it further includes a constant temperature device 50. The constant temperature device 50 is respectively communicated with the sequencing batch partial nitrification reaction device 20 and the anaerobic ammonium oxidation reaction device 40 with an expanded granular sludge bed through a plurality of pipelines 80; the constant temperature device 50 is used to adjust the temperature in the sequencing batch partial nitrification reaction device 20 and the anaerobic ammonium oxidation reaction device 40 with an expanded granular sludge bed to any temperature value and control the temperature to be maintained at the temperature value.

[0080] The constant temperature device 50 is respectively connected with the sequencing batch partial nitrification reaction device 20 and the anaerobic ammonium oxidation reaction device 40 with an expanded granular sludge bed through a plurality of pipelines 80 to form a comprehensive temperature control network. The constant temperature device 50 is used to adjust the temperature in these two reaction devices to meet the optimal temperature requirements under different reaction conditions. Through the constant temperature device 50, the system can adjust the temperature of the sequencing batch partial nitrification reaction device 20 and the anaerobic ammonium oxidation reaction device 40 with an expanded granular sludge bed to any set temperature value and ensure that the temperature is stably maintained at the set value during operation. It can optimize the microbial activity and reaction efficiency, and then affect the biochemical reaction rate and microbial metabolism, etc.

[0081] The constant temperature device 50 can not only have heating and cooling functions, but also be equipped with a temperature sensor and a controller, which can monitor and adjust temperature changes in real time to ensure that the system can operate efficiently under various environmental conditions. In addition, the design of the constant temperature device 50 takes into account energy efficiency and environmental protection, adopting energy-saving technologies to reduce energy consumption and at the same time reduce the impact on the environment.

[0082] Furthermore, as Figure 1 shown, it further includes a water inlet device 10 and a plurality of stirring devices 60; the water inlet device 10 is connected to the sequencing batch partial nitrification reaction device 20, and the water inlet device 10 is used to store the wastewater to be treated; the plurality of stirring devices 60 are respectively arranged in the water inlet device 10, the sequencing batch partial nitrification reaction device 20, and the adjustment device 30; the plurality of stirring devices 60 are used for stirring.

[0083] The water inlet device 10 is connected to the sequencing batch partial nitrification reaction device 20 and is used to store the wastewater to be treated to ensure that the system can continuously and stably receive and treat the input wastewater flow.

[0084] To optimize the wastewater treatment process, the system is equipped with stirring devices 60 at multiple key positions, for example, it can be arranged in the water inlet device 10, the sequencing batch partial nitrification reaction device 20, and the adjustment device 30. The stirring device 60 is used to ensure the uniform mixing of wastewater and reactants in each device through mechanical uniform or non-uniform stirring. In the water inlet device 10, the stirring device 60 helps prevent solid substances from precipitating and maintains the uniformity of the wastewater, thereby improving the efficiency of subsequent treatment. In the sequencing batch partial nitrification reaction device 20, the stirring device 60 ensures sufficient contact between reactants and microorganisms and promotes the smooth progress of the nitrification reaction. In the adjustment device 30, the stirring device 60 helps maintain uniform reaction conditions to ensure that the properties of the wastewater meet the expected treatment standards. The stirring device 60 not only improves the efficiency of each treatment stage, but also enhances the overall stability and reliability of the system by optimizing the mixing conditions. At the same time, the comprehensive stirring system can better adapt to different wastewater characteristics and provide efficient and stable treatment effects.

[0085] Furthermore, as Figure 1 shown, it further includes a plurality of electric pumps 70; at least one electric pump 70 is correspondingly arranged on each of the pipelines 80.

[0086] Multiple electric pumps 70 are respectively arranged on multiple pipelines 80, forming an efficient fluid transportation network. The arrangement of multiple electric pumps 70 ensures that the fluid in different treatment stages can be smoothly transported to each reaction device and regulating device. The main function of the electric pump 70 is to provide the necessary power to promote the circulation and transmission of wastewater and treatment liquid in the system. Through these electric pumps, the system can overcome the flow resistance in the pipeline and ensure the rapid and stable flow of the fluid between each device. This is crucial for maintaining the continuity and treatment efficiency of the system.

[0087] Between the sequencing batch partial nitrification reaction device 20 and the expanded granular sludge bed anaerobic ammonium oxidation reaction device 40, the electric pump 70 ensures that the treated wastewater can be quickly transferred to the next treatment stage, avoiding unnecessary residence time and thus improving the overall treatment efficiency. In the water inlet device 10 and the regulating device 30, the electric pump 70 helps to precisely control the flow rate to ensure that each treatment stage can proceed under the best conditions.

[0088] The embodiment of the present application also provides a method for denitrifying methylamine wastewater based on partial nitrification - anaerobic ammonium oxidation. Using any one of the above - mentioned embodiments, as Figure 2 shown, the method includes the following steps:

[0089] S201. Inject the wastewater to be treated into the sequencing batch partial nitrification reaction device 20, add strains, and control the aeration time and / or aeration intensity to carry out nitrification reaction.

[0090] S202. After the nitrification reaction is completed, the wastewater is injected from the sequencing batch partial nitrification reaction device 20 into the regulating device 30, and detect whether the values of nitrate nitrogen and ammonia nitrogen in the wastewater reach the predetermined values.

[0091] S203. Then inject the wastewater from the regulating device 30 into the expanded granular sludge bed anaerobic ammonium oxidation reaction device 40 to carry out anaerobic ammonium oxidation denitrification treatment.

[0092] S204. Then inject the wastewater from the regulating device into the sequencing batch partial nitrification reaction device 20, and control the aeration time and / or aeration intensity to adjust the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater.

[0093] Specifically, after the wastewater enters the sequencing batch partial nitrification reaction device 20, it is aerated for 5 - 60 min first, then the aeration is stopped, and it is stirred for 30 - 120 min to generate a partial nitrification reaction inside, and a part of ammonia nitrogen is converted into nitrite nitrogen. Then it is left standing for 5 - 60 min. After the mud - water separation, the effluent enters the regulating device 30. Under the stable operation of the system, the regulating device 30 feeds water into the bottom of the expanded granular sludge bed anaerobic ammonium oxidation reaction device 40, and the anaerobic ammonium oxidation reaction occurs inside, and the mixed liquid exits through the three - phase separator.

[0094] Further, in the above embodiments, the ratio of nitrite nitrogen to ammonia nitrogen in the predetermined value is 0.8 to 1.8, preferably 1 to 1.5; and / or, the aeration intensity is 0.05 to 0.5 L / min, preferably 0.15 to 0.25 L / min; and / or, the aeration time is 5 to 60 min, preferably 10 to 30 min.

[0095] Using any implementation method in any of the above embodiments, the methylamine wastewater is subjected to denitrification treatment. A sequencing batch partial nitrification reactor with an effective volume of 2 L and an expanded granular sludge bed anaerobic ammonium oxidation reactor with an effective volume of 0.5 L are selected and operated under the condition of 20 to 40 °C. This embodiment treats the effluent after anaerobic digestion of industrial methylamine wastewater, and its main physical and chemical properties are: 120 mg / L ammonia nitrogen, 50 mg / L COD (chemical oxygen demand), and trace amounts of organic matter help the remaining nitrate nitrogen to be denitrified, thereby achieving deep denitrification; it is started and operated with a hydraulic retention time of 12 h, and then shortened to 8 h. By Figure 3 and Figure 4 It can be seen that when the hydraulic retention time is 12 and 8 h, the system operates stably, the denitrification efficiency is excellent, and 100% ammonia nitrogen removal is achieved.

[0096] And during the above denitrification treatment process, tests on partial nitrification performance, anaerobic ammonium oxidation denitrification performance, microbial anaerobic ammonium oxidation activity, and sludge sedimentation performance of the anaerobic ammonium oxidation reaction device are carried out, and the results are as Figures 3 to 6 shown.

[0097] Figure 3 It is a line graph of partial nitrification performance (Note: NO 2 - -N: Nitrite nitrogen, which refers to the intermediate product in the process of further oxidation of nitrogen-containing organic matter in water and becoming nitrate; NH 4 + -N: Combined nitrogen in the form of ammonia or ammonium ions, that is, the nitrogen in water in the form of free ammonia (NH 3 ) and ammonium ions (NH 4 + ); NO 3 - -N: The final product of the oxidation and decomposition of nitrogen-containing organic matter. The nitrogen in water in the form of nitrate is of low toxicity or non-toxic), such as Figure 3As shown, the horizontal axis represents the reaction time in days. The start time of the reaction is set as 0d, and samples are taken every two to three days for measurement to observe the changes in the influent and effluent water quality of the reactor. The left vertical axis represents the cumulative rates of nitrite nitrogen and nitrate nitrogen in the partial nitrification section, that is, the ratios of the nitrite nitrogen produced by conversion to the influent ammonia nitrogen and the nitrate nitrogen produced by conversion to the influent ammonia nitrogen respectively. These indicators can characterize the activity of the strains inside the partial nitrification reactor; the right vertical axis represents the ratio of nitrite nitrogen to ammonia nitrogen in the effluent of partial nitrification, and this value can represent whether the effluent of the partial nitrification section can meet the influent requirements of the subsequent anaerobic ammonium oxidation section.

[0098] Figure 4 It is a line graph of the denitrification performance of anaerobic ammonium oxidation. Among them, -Inf: the influent water of this reaction stage; -Eff: the effluent water of this reaction stage; -BC and -CK: parallel groups to each other; as Figure 4 shown, the horizontal axis is the reaction time in days. We set the start time of the reaction as 0d. For the subsequent engineering application of the reaction system, the water treatment capacity of the reactor is used as a variable to seek the optimal treatment conditions. The reaction process is divided into three stages. The first stage is the start-up stage of the reactor. The influent water volume in the start-up stage is 4L. After the reactor operates stably, the daily influent water volume is increased to 4.5L as the second stage, and the daily influent water volume in the third stage is 6L. The vertical axis is the measured ammonia nitrogen concentration. According to Figure 4 the example, it can be seen that the average concentration of ammonia nitrogen entering the reaction system is 100mg / L, the concentration ratio of nitrite nitrogen to ammonia nitrogen in the effluent of the partial nitrification section is about 1, and the anaerobic ammonium oxidation section can efficiently treat the effluent of partial nitrification. The final effluent ammonia nitrogen of the anaerobic ammonium oxidation section is less than 5mg / L. To sum up, the reaction system can efficiently treat the nitrogen in methylamine wastewater.

[0099] Figure 5 It is a bar graph of the anaerobic ammonium oxidation activity of microorganisms (Note: The anaerobic ammonium oxidation activity (SAA) is measured by NH 4 + -N / VSS, mg / gVSS / h; the nitrite nitrogen reduction activity (SDA 2 ) is measured by NO 2 - -N / VSS, mg / gVSS / h; the nitrate nitrogen reduction activity (SDA 3 ) is measured by NO 3 - -N / VSS, mg / gVSS / h), as Figure 5As shown, the horizontal axis represents the reaction rates of anaerobic ammonium oxidation sludge to different substrates before and during the reaction. SAA and SDA2 can represent the microbial denitrification activity of the anaerobic ammonium oxidation system. The slight increase indicates that the adaptability of anaerobic ammonium oxidation bacteria to wastewater is gradually increasing, and the denitrification performance is improving. Among them, SDA3 increases from the original stage to 1.33 in the next stage, indicating that the denitrification process has been enhanced, the nitrate nitrogen in the system has been reduced, and the nitrate nitrogen content in the effluent has been decreased. That is, with the increase of the operation time, the anaerobic ammonium oxidation activity has a slow increase.

[0100] Figure 6 and Figure 7 are bar charts of sludge sedimentation performance (MLSS - Mixed liquid suspended solids: the concentration of suspended solids in the mixed liquid of sewage and activated sludge in the aeration tank, which refers to the quantity of suspended solids in the mixed liquid, with the unit of mg / L; MLVSS - Mixed Liquor Volatile Suspended Solids: the concentration of the organic solid matter part in the activated sludge, with the unit of mg / L). As Figure 6 and Figure 7 shown, it can be seen that from the end of stage I to the end of stage II, the average sludge sedimentation rate increases from 51.6 ± 7.3 to 75.7 ± 6.7 m / h, indicating that the sludge sedimentation performance has been significantly improved, which shows that the reactor has good sludge-water separation performance and good effluent quality. That is, with the increase of the operation time, the sedimentation performance of anaerobic ammonium oxidation sludge has been significantly improved, making the sludge-water separation effect better and the effluent quality better.

[0101] It should be noted that for the foregoing method embodiments, for the sake of simple description, they are all expressed as a series of action combinations. However, those skilled in the art should know that this application is not limited by the described action sequence, because according to this application, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily essential to this application.

[0102] The embodiments or implementation manners in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other.

[0103] It should be noted that phrases such as "in specific implementation", "in some embodiments", "in this embodiment", "exemplarily", etc. mentioned in the specification indicate that the described embodiments may include specific features, structures or characteristics, but not necessarily every embodiment includes such specific features, structures or characteristics. In addition, such phrases do not necessarily refer to the same embodiment. Moreover, when combining specific features, structures or characteristics with embodiments, it is within the knowledge scope of those skilled in the art to implement such features, structures or characteristics in combination with other embodiments, whether explicitly or implicitly described.

[0104] Generally speaking, terms should be understood at least in part by their use in context. For example, at least in part according to the context, the term "one or more" used in the text can be used to describe any feature, structure or characteristic in the sense of singularity, or can be used to describe a combination of features, structures or characteristics in the sense of plurality. Similarly, at least in part according to the context, terms such as "a" or "the" can also be understood to convey singular usage or plural usage.

[0105] It should be easily understood that the terms "on", "above" and "over" in this disclosure should be interpreted in the broadest way, so that "on" not only means "directly on something", but also includes the meaning of "on something" with intermediate features or layers therebetween, and "above" or "over" not only includes the meaning of "above" or "over something", but also can include the meaning of "above" or "over something" with no intermediate features or layers therebetween (i.e., directly on something).

[0106] In addition, in order to facilitate the description, spatial relative terms such as "below", "beneath", "under", "above", "over", etc. may be used in the text to describe the relationship of one element or feature relative to other elements or features as shown in the figures. Spatial relative terms are intended to include different orientations of the device in use or operation in addition to the orientation shown in the drawings. The device may have other orientations (rotated 90 degrees or in other orientations), and the spatial relative descriptive terms used in the text can be correspondingly interpreted as well. In the above embodiments, the descriptions of the respective embodiments have their own emphases. For parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments. The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope described in this specification.

[0107] Furthermore, in the description of the present invention, it should also be noted that the orientation or positional relationship indicated by terms such as "front" and "rear" is based on the orientation or positional relationship, or the orientation or positional relationship in which the inventive product is usually placed during use. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. In addition, terms such as "first" and "second" are only used for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0108] Those skilled in the art will readily conceive of other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include common general knowledge or conventional technical means in the technical field not disclosed in the present application. The specification and examples are only regarded as exemplary, and the true scope and spirit of the present application are pointed out by the following claims.

[0109] It should be understood that the present application is not limited to the precise structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present application is only limited by the appended claims.

Claims

1. A methylamine wastewater denitrification system based on partial nitrification-anaerobic ammonium oxidation, characterized in that: include: A sequencing batch partial nitrification reaction device (20), a regulating device (30) and an expanded granular sludge bed anaerobic ammonia oxidation reaction device (40); The sequencing batch partial nitrification reaction device (20) and the expanded granular sludge bed anaerobic ammonia oxidation reaction device (40) are respectively connected to the regulating device (30) through a plurality of pipelines (80); The sequencing batch partial nitrification reaction device (20) is used for nitrification reaction of wastewater and bacterial strains, and the aeration intensity and / or aeration time in the sequencing batch partial nitrification reaction device (20) are controlled to adjust the dissolved oxygen concentration in the sequencing batch partial nitrification reaction device (20) and regulate the progress of the nitrification reaction; The regulating device (30) is used to detect and monitor the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater in the sequencing batch partial nitrification reaction device (20), so that the wastewater whose ratio reaches a predetermined value is injected into the expanded granular sludge bed anaerobic ammonia oxidation reaction device (40); The expanded granular sludge bed anaerobic ammonium oxidation reaction device (40) is used to perform anaerobic ammonium oxidation treatment on the wastewater reaching the preset value, and to discharge the treated clean water.

2. The system according to claim 1, characterized in that The sequencing batch partial nitrification reaction device (20) is provided with an aerator (21); The aerator (21) is connected to the bottom end of the sequencing batch partial nitrification reaction device (20), and the aerator (21) is used to control the aeration intensity and / or aeration time, adjust the dissolved oxygen concentration in the sequencing batch partial nitrification reaction device (20), and regulate the progress of the nitrification reaction.

3. The system according to claim 2, characterized in that The sequencing batch partial nitration reaction device (20) is provided with a filtering device (22), and the filtering device (22) is connected to the regulating device (30); The filtering device (22) is used to filter the wastewater flowing from the sequencing batch partial nitrification reaction device (20) into the regulating device (30).

4. The system according to claim 1, characterized in that The expanded granular sludge bed anaerobic ammonia oxidation reaction device (40) is provided with a three-phase separator (41); The three-phase separator (41) is arranged at the top of the expanded granular sludge bed anaerobic ammonium oxidation reaction device (40), and the three-phase separator (41) is connected to the expanded granular sludge bed anaerobic ammonium oxidation reaction device (40); The three-phase separator (41) is used to discharge the clean water and / or gas generated after the anaerobic ammonium oxidation reaction in the expanded granular sludge bed anaerobic ammonium oxidation reaction device (40) to the outside of the expanded granular sludge bed anaerobic ammonium oxidation reaction device (40).

5. The system according to claim 1, characterized in that It also includes a constant temperature device (50), wherein the constant temperature device (50) is respectively connected to the sequencing batch partial nitrification reaction device (20) and the expanded granular sludge bed anaerobic ammonia oxidation reaction device (40) through the multiple pipes (80); The thermostatic device (50) is used to adjust the temperature in the sequencing batch partial nitrification reaction device (20) and the expanded granular sludge bed anaerobic ammonia oxidation reaction device (40) to any temperature value, and control the temperature to be maintained at the temperature value.

6. The system according to claim 5, characterized in that It also includes a water inlet device (10) and a plurality of stirring devices (60); The water inlet device (10) is connected to the sequencing batch partial nitrification reaction device (20), and the water inlet device (10) is used to store wastewater to be treated; The multiple stirring devices (60) are respectively arranged in the water inlet device (10), the sequencing batch partial nitration reaction device (20), and the regulating device (30); the multiple stirring devices (60) are used for stirring.

7. The system according to claim 6, characterized in that Also included are a plurality of electric pumps (70); At least one electric pump (70) is correspondingly arranged on each of the pipelines (80).

8. A method for denitrification of methylamine wastewater based on partial nitrification-anaerobic ammonium oxidation, using the system according to any one of claims 1 to 7, characterized in that: The steps include: Injecting the wastewater to be treated into the sequencing batch partial nitrification reaction device (20), adding bacteria, and controlling the aeration time and / or aeration intensity to carry out nitrification reaction; After the nitrification reaction is completed, the wastewater is injected from the sequencing batch partial nitrification reaction device (20) into the regulating device (30), and the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater is detected to determine whether it reaches the predetermined value; The wastewater reaching the predetermined value is injected from the regulating device (30) into the expanded granular sludge bed anaerobic ammonia oxidation reaction device (40) to undergo anaerobic ammonia oxidation denitrification treatment, and the treated clean water is discharged.

9. The method according to claim 8, characterized in that The detecting whether the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater reaches the predetermined value comprises: If yes, injecting the wastewater from the regulating device (30) into the expanded granular sludge bed anaerobic ammonia oxidation reaction device (40); If not, the wastewater is injected from the regulating device (30) into the sequencing batch partial nitrification reaction device (20), and the aeration time and / or aeration intensity are controlled to adjust the ratio of nitrite nitrogen to ammonia nitrogen in the wastewater.

10. The method according to claim 8, characterized in that The ratio of nitrite nitrogen to ammonia nitrogen in the predetermined value is 0.8 to 1.8; And / or, the aeration intensity is 0.05 to 0.5 L / min; And / or, the aeration time is 5 to 60 minutes.

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