MBR membrane mainstream anaerobic ammonium oxidation treatment device and method suitable for municipal sewage

Abstract

The present invention discloses an MBR membrane-based mainstream anaerobic ammonium oxidation treatment device and method suitable for municipal sewage, which relates to the field of sewage treatment and includes an SND / A unit, a PDA unit, an M / SND unit, and a reflow unit. The SND / A unit is used to remove nitrogen through simultaneous nitrification and denitrification reactions, short-cut nitrification anaerobic ammonium oxidation reactions, and short-cut denitrification anaerobic ammonium oxidation reactions. The PDA unit is connected to the rear stage of the SND / A unit and is used to remove nitrogen through short-cut denitrification anaerobic ammonium oxidation reactions. The M / SND unit is connected to the rear stage of the PDA unit and includes an MBR filter membrane and a scrubbing aeration element for aerating and scrubbing the MBR filter membrane, which is used to filter and form treated water and activated sludge. The reflow unit is used to connect the M / SND and the SND / A unit to reflow the activated sludge to the SND / A unit. The bacteria disclosed in the present invention will not be passively lost and can operate stably in a low-temperature environment.

Description

Technical Field

[0001] The present disclosure relates to the technical field of sewage treatment, and in particular to an MBR membrane mainstream anaerobic ammonia oxidation treatment device and method suitable for municipal sewage. Background Art

[0002] The water quality of domestic municipal sewage mostly shows the characteristics of low carbon-nitrogen ratio. As the emission standards in various places have higher requirements for the effluent quality of sewage treatment plants, and because municipal sewage contains ammonia nitrogen, many sewage treatment plants need to add more external carbon sources to ensure that the total nitrogen in the effluent meets the standards, resulting in excessively high sewage treatment operating costs. In addition, traditional denitrification methods also have problems such as large aeration volume, high operating energy consumption, and high carbon source consumption.

[0003] Anaerobic ammonium oxidation is a highly efficient wastewater treatment and denitrification process. However, the current mainstream anaerobic ammonium oxidation process for municipal sewage or sewage with similar water quality characteristics, that is, the process in which all sewage is treated by anaerobic ammonium oxidation, basically adopts biological carriers, granular sludge or discontinuous flow, and has difficulties such as difficulty in stable operation in low water temperature environment. Low water temperature anaerobic ammonium oxidation is usually only applicable to side stream processes, such as when one part of the sewage is treated by anaerobic ammonium oxidation and the other part is treated by traditional A 2 The side stream process of O treatment is mainly because the growth and enrichment rate of anaerobic ammonium oxidizing bacteria at low temperatures is often lower than the rate of SS loss through the effluent of the secondary sedimentation tank. The passive loss of anaerobic ammonium oxidizing bacteria with the effluent makes it difficult to operate the sewage treatment stably in a low temperature environment. Summary of the Invention

[0004] In view of the above-mentioned shortcomings of the prior art, the purpose of the present disclosure is to provide an MBR membrane mainstream anaerobic ammonia oxidation treatment device and method suitable for municipal sewage, which can continuously and stably treat municipal sewage under normal water temperature and low water temperature conditions in winter.

[0005] The MBR membrane mainstream anaerobic ammonium oxidation treatment device disclosed in the present invention is suitable for municipal sewage, comprising: an SND / A unit having a first sewage treatment chamber and an oxygenating component for oxygenating the first sewage treatment chamber, for simultaneous nitrification and denitrification reaction, short-cut nitrification anaerobic ammonium oxidation reaction and short-cut denitrification anaerobic ammonium oxidation reaction to treat municipal sewage, so as to nitrify ammonia nitrogen into nitrate and denitrify nitrate into nitrogen gas for denitrification, short-cut nitrification of ammonia nitrogen into nitrite and anaerobic ammonium oxidation reaction of nitrite and ammonia nitrogen into nitrogen gas for denitrification, and short-cut denitrification of nitrite into nitrite and anaerobic ammonium oxidation reaction of nitrite and ammonia nitrogen into nitrogen gas for denitrification, so as to denitrify and form treated sewage in one step; a PDA unit The M / SND unit is connected to the rear stage of the SND / A unit and is used for treating the primary treated sewage by a short-cut denitrification anaerobic ammonium oxidation reaction, so that nitrate is short-cut denitrified into nitrite and nitrite reacts with ammonia nitrogen to form nitrogen gas for secondary denitrification and forming secondary treated sewage; the M / SND unit is connected to the rear stage of the PDA unit and includes an MBR filter membrane and a scrubbing aeration member for aerating and scrubbing the MBR filter membrane, so as to filter and treat the secondary treated sewage to form treated water and activated sludge; and a reflux unit is used for connecting the M / SND unit and the SND / A unit and for returning the activated sludge to the SND / A unit.

[0006] According to some examples of the present disclosure, nitric oxide is also generated as a byproduct in the simultaneous nitrification and denitrification reaction, the shortcut nitrification and anaerobic ammonium oxidation reaction, and the shortcut denitrification and anaerobic ammonium oxidation reaction;

[0007] The anaerobic ammonium oxidizing bacteria in the SND / A unit and / or PDA unit include bacteria that can utilize nitrite and nitric oxide to oxidize ammonia nitrogen.

[0008] According to some examples of the present disclosure, it further includes: a sewage supply unit, which is connected to the SND / A unit and the PDA unit respectively.

[0009] According to some examples of the present disclosure, a first oxygen concentration detection element and a first redox potential detection element are provided in the SND / A unit; the MBR membrane mainstream anaerobic ammonia oxidation treatment device suitable for municipal sewage further includes: a control unit, connected to the first oxygen concentration detection element and the first redox potential detection element, respectively, for adjusting the oxygenation flow rate of the oxygenation component to balance the oxygen consumption and oxygenation amount of the SND / A unit according to the positive correlation fluctuation of the detection data of the first oxygen concentration detection element and the first redox potential detection element, and the fluctuation amount of the detection data of the first redox potential detection element is outside a first preset range; and / or

[0010] The PDA unit is provided with a second oxygen concentration detection element and a second oxidation-reduction potential detection element, which are used to assist in determining whether the oxygen consumption and oxygen supply of the SND / A unit are balanced based on whether the detection data of the second oxygen concentration detection element and the second oxidation-reduction potential detection element are within a second preset range when the detection data of the second oxygen concentration detection element and the second oxidation-reduction potential detection element fluctuate in a positive correlation.

[0011] According to some examples of the present disclosure, the M / SND unit is provided with an oxygen supply component located in the front stage of its MBR filter membrane, and the M / SND unit is provided with a third oxygen concentration detection component and a third redox potential detection component;

[0012] The MBR membrane mainstream anaerobic ammonia oxidation treatment device suitable for municipal sewage also includes: a control unit, which is respectively connected to the third oxygen concentration detection element and the third oxidation-reduction potential detection element, and is used to adjust the oxygen supply flow rate of the oxygen supply component to balance the oxygen consumption and oxygen supply amount of the M / SND unit according to the positive correlation fluctuation of the detection data of the third oxygen concentration detection element and the third oxidation-reduction potential detection element, and the fluctuation amount of the detection data of the third oxidation-reduction potential detection element is outside a third preset range.

[0013] According to some examples of the present disclosure, the M / SND unit further provides for simultaneous nitrification and denitrification reaction to treat the secondary treated sewage, so as to nitrify ammonia nitrogen into nitrate and denitrify nitrate into nitrogen gas for denitrification.

[0014] The present disclosure also provides an MBR membrane mainstream anaerobic ammonium oxidation treatment method applicable to municipal sewage, comprising: passing municipal sewage into an oxygenated SND / A unit, wherein the SND / A unit is used for simultaneous nitrification and denitrification reaction, short-cut nitrification anaerobic ammonium oxidation reaction and short-cut denitrification anaerobic ammonium oxidation reaction to treat municipal sewage, so that ammonia nitrogen is nitrified into nitrate and nitrate is denitrified into nitrogen gas for denitrification, ammonia nitrogen is short-cut nitrified into nitrite and nitrite and ammonia nitrogen are anaerobic ammonium oxidation reacted into nitrogen gas for denitrification, and nitrate is short-cut denitrified into nitrite and nitrite and ammonia nitrogen are anaerobic ammonium oxidation reacted into nitrogen gas for denitrification, so as to denitrify and form a treated sewage once; The primary treated sewage is passed into an unoxygenated PDA unit, wherein the PDA unit provides a short-cut denitrification anaerobic ammonium oxidation reaction to treat the primary treated sewage, so that nitrate is short-cut denitrified into nitrite and nitrite reacts with ammonia nitrogen to form nitrogen gas for anaerobic ammonium oxidation, thereby performing secondary denitrification and forming secondary treated sewage; the secondary treated sewage is passed into an M / SND unit, wherein the M / SND unit includes an MBR filter membrane and a scrubbing aeration member for aerating and scrubbing the MBR filter membrane, so as to form treated water and activated sludge; and the activated sludge of the M / SND unit is returned to the SND / A unit through a reflux unit.

[0015] According to some examples of the present disclosure, nitric oxide is also generated as a byproduct in the simultaneous nitrification and denitrification reaction, the short-cut nitrification anaerobic ammonium oxidation reaction, and the short-cut denitrification anaerobic ammonium oxidation reaction; the anaerobic ammonium-oxidizing bacteria in the SND / A unit and / or the PDA unit include bacteria that can utilize nitrite and nitric oxide to oxidize ammonia nitrogen; and / or

[0016] The current reflux ratio of the reflux unit is negatively correlated with the current dissolved oxygen concentration in the SND / A unit; and / or

[0017] In the M / SND unit, the secondary treated wastewater is also treated by simultaneous nitrification and denitrification, so that ammonia nitrogen is nitrified into nitrate and nitrate is denitrified into nitrogen gas for denitrification; and / or

[0018] When the sewage is introduced, part of the municipal sewage is directly introduced into the SND / A unit, and part of the municipal sewage is directly introduced into the PDA unit.

[0019] According to some examples of the present disclosure, based on the fact that the dissolved oxygen concentration in the SND / A unit fluctuates in a positive correlation with the redox potential, and the fluctuation amount of the redox potential is outside a first preset range, the oxygen filling flow rate is adjusted to balance the oxygen filling amount and oxygen consumption in the SND / A unit; and / or;

[0020] When the dissolved oxygen concentration in the PDA unit fluctuates in a positive correlation with the redox potential, assisting in determining whether the oxygen consumption and oxygen supply of the SND / A unit are balanced based on whether the fluctuation amount of the redox potential is within a second preset range; and / or;

[0021] Based on the fact that the dissolved oxygen concentration in the M / SND unit fluctuates in a positive correlation with the redox potential, and the fluctuation amount of the redox potential is outside a third preset range, the oxygen supplement flow rate of the M / SND unit is adjusted to balance the oxygen consumption and oxygen supplement amount of the nitrification reaction in the M / SND unit.

[0022] According to some examples of the present disclosure, in the SND / A unit, the dissolved oxygen concentration is 0.02-0.5 mg / L, the activated sludge concentration is 2500-15000 mg / L, and the gas-water ratio is 0.5-2.0:1; and / or

[0023] In the M / SND unit, the dissolved oxygen concentration is 0.1-0.5 mg / L, the activated sludge concentration is 3000-30000 mg / L, and the air-water ratio of the scrubbing aeration element is less than 6:1 (optimally less than 3:1).

[0024] Beneficial effects:

[0025] (1) The MBR membrane mainstream anaerobic ammonia oxidation treatment device and method disclosed herein, which is applicable to municipal sewage, couples two-stage anaerobic ammonia oxidation with membrane separation, and is used in the mainstream treatment process of municipal sewage (or sewage with water quality characteristics similar to municipal sewage). It adopts a continuous flow operation mode and is not only applicable to sewage treatment processes at room temperature, but also to the adverse operating environment of low water temperature in winter.

[0026] (2) The MBR membrane-based mainstream anaerobic ammonia oxidation treatment device and method disclosed herein, which is applicable to municipal sewage, does not require an aerobic tank, consumes little oxygen and energy during operation, and has low operating costs.

[0027] (3) The MBR membrane mainstream anaerobic ammonia oxidation treatment device and method disclosed herein, which is applicable to municipal sewage, utilizes anaerobic ammonia oxidation bacteria that can directly react with ammonia nitrogen using nitric oxide as a reaction substrate to treat ammonia nitrogen. Nitric oxide, an intermediate byproduct of sewage treatment, is removed, and ammonia nitrogen can be further removed.

[0028] (4) The MBR membrane mainstream anaerobic ammonia oxidation treatment device and method disclosed herein, which is applicable to municipal sewage, has a method in which raw water and sewage are introduced into both the SND / A unit and the PDA unit, which is conducive to fully utilizing the carbon source in the raw water and sewage and saving external carbon sources.

[0029] (5) The MBR membrane mainstream anaerobic ammonia oxidation treatment device and method disclosed in the present invention is applicable to municipal sewage, and does not require an aerobic tank, thereby saving the operating energy consumption of the aeration equipment.

[0030] (6) The MBR membrane-based mainstream anaerobic ammonium oxidation treatment device and method disclosed herein, which is applicable to municipal sewage, realizes the separation of sludge age (SRT) and hydraulic retention time (HRT) by introducing an MBR membrane separation device. The long sludge age is conducive to the enrichment of anaerobic ammonium oxidizing bacteria with a relatively slow growth rate. The membrane solid-liquid separation method can intercept bacteria, avoiding the passive loss of anaerobic ammonium oxidizing bacteria through the effluent SS of the secondary sedimentation tank in the traditional secondary sedimentation tank solid-liquid separation method. Under low water temperature conditions in winter, the growth of anaerobic ammonium oxidizing bacteria is even slower. In winter, the membrane tank can be selected to actively discharge no sludge or less sludge to achieve the enrichment of anaerobic ammonium oxidizing bacteria.

[0031] (7) The MBR membrane mainstream anaerobic ammonia oxidation treatment device and method for municipal sewage disclosed herein have good adaptive resilience and do not require the carbon-nitrogen ratio (C / N ratio) of the influent municipal sewage to be adjusted through pretreatment facilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the layout of an MBR membrane mainstream anaerobic ammonia oxidation treatment device suitable for municipal sewage according to an embodiment of the present disclosure.

[0033] Figure 2It is a flow chart of an MBR membrane mainstream anaerobic ammonia oxidation treatment method applicable to municipal sewage according to an embodiment of the present disclosure.

[0034] Reference numerals:

[0035] SND / A unit 11; first sewage treatment chamber 111; oxygenation component 112; first oxygen concentration detection component 113; first oxidation-reduction potential detection component 114; first stirring component 115;

[0036] PDA unit 12; second sewage treatment chamber 121; second oxygen concentration detection element 122; second oxidation-reduction potential detection element 123; second stirring element 124;

[0037] M / SND unit 13; housing 131; oxygen supply chamber 1311; filter chamber 1312; partition 1313; MBR filter membrane 132; scrubbing aeration element 133; oxygen supply component 134; third oxygen concentration detection element 135; third redox potential detection element 136;

[0038] Reflux unit 14; reflux pipe 141; reflux drive 142;

[0039] Air supply unit 15; first air supply pipe 151; first air supply valve 1511; second air supply pipe 152; second air supply valve 1521; first air supply drive 153; third air supply pipe 154; second air supply drive 155;

[0040] Sewage supply unit 16; water supply main pipe 161; first water supply branch pipe 162; first water supply valve 1621; second water supply branch pipe 163; second water supply valve 1631;

[0041] Water outlet unit 17; water outlet pipe 171; water outlet driving member 172. DETAILED DESCRIPTION

[0042] The following describes the embodiments of the present disclosure through specific examples. Those skilled in the art can easily understand the other advantages and effects of the present disclosure from the information disclosed in this disclosure. The present disclosure can also be implemented or applied through different specific embodiments. The details of the present disclosure can also be modified or changed according to different viewpoints and application modules without departing from the spirit of the present disclosure. It should be noted that the embodiments and features in the embodiments of the present disclosure can be combined with each other unless there is a conflict.

[0043] The following is a detailed description of the embodiments of the present disclosure with reference to the accompanying drawings so that those skilled in the art can easily implement the present disclosure. The present disclosure can be embodied in many different forms and is not limited to the embodiments described herein.

[0044] Throughout the present disclosure, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present disclosure. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or a group of embodiments or examples. Furthermore, those skilled in the art may combine and integrate different embodiments or examples, and features of different embodiments or examples, as described in the present disclosure, without conflicting requirements.

[0045] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the context of this disclosure, "a group" means two or more, unless otherwise specifically defined.

[0046] In order to clearly describe the present disclosure, components not related to the description are omitted, and the same or similar components throughout the specification are denoted by the same reference numerals.

[0047] Throughout this specification, when a device is said to be "connected" to another device, this includes not only "direct connection" but also "indirect connection" with other elements interposed therebetween. Furthermore, when a device is said to "include" a certain component, unless otherwise stated, this does not exclude the inclusion of other components but rather implies that the device may include other components.

[0048] Although the terms first, second, etc. are used in this document to represent various elements in some examples, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, the first interface and the second interface, etc. are represented. Furthermore, as used in this document, the singular forms "one," "an," and "the" are intended to also include the plural forms, unless there is a contrary indication in the context. It should be further understood that the terms "comprise" and "include" indicate the presence of the described features, steps, operations, elements, modules, projects, types, and / or groups, but do not exclude the presence, occurrence, or addition of one or a group of other features, steps, operations, elements, modules, projects, types, and / or groups. The terms "or" and "and / or" used herein are interpreted as inclusive, or mean any one or any combination. Therefore, "A, B, or C" or "A, B, and / or C" means "any of the following: A; B; C; A and B; A and C; B and C; A, B, and C." Exceptions to this definition only occur when the combination of elements, functions, steps, or operations is inherently mutually exclusive in some way.

[0049] The technical terms used herein are intended only to refer to specific embodiments and are not intended to limit the present disclosure. The singular form used herein also includes the plural form unless the statement explicitly indicates otherwise. The term "comprising" as used in this specification is intended to specify specific features, regions, integers, steps, operations, elements, and / or components and does not exclude the presence or addition of other features, regions, integers, steps, operations, elements, and / or components.

[0050] Although not defined differently, all terms used herein, including technical and scientific terms, have the same meanings as those generally understood by those skilled in the art to which this disclosure belongs. Terms defined in commonly used dictionaries are additionally interpreted as having meanings consistent with relevant technical literature and the current message. Unless otherwise defined, they should not be overly interpreted as ideal or highly formalized meanings.

[0051] The devices used to treat ammonia nitrogen wastewater in related technologies consume a large amount of oxygen, the operating energy consumption of the oxygen supply equipment is high, and bacteria are easily lost, especially for the treatment of low ammonia nitrogen concentration in the influent (ammonia nitrogen concentration ≤ 60 mg / L) at low water temperature in winter (water temperature ≥ 7°C). There are no reports on the application of mainstream anaerobic ammonia oxidation processes in related technologies.

[0052] In view of this, the present disclosure provides an anaerobic ammonia oxidation treatment device for treating municipal sewage, but it can be understood that in addition to municipal sewage, other sewage containing ammonia nitrogen with influent water quality similar to municipal sewage is also within the protection scope of the present disclosure, and during the treatment process of the device disclosed in the present disclosure, bacteria will not be passively lost, and ammonia nitrogen sewage can be continuously treated under normal temperature and low water temperature conditions in winter.

[0053] Figure 1 This is a schematic diagram of the layout of an MBR membrane mainstream anaerobic ammonium oxidation treatment device suitable for municipal sewage according to an embodiment of the present disclosure. Figure 1 The MBR membrane mainstream anaerobic ammonia oxidation treatment device for municipal sewage according to the embodiment of the present disclosure includes an SND / A unit 11, a PDA unit 12, an M / SND unit 13 and a reflux unit 14.

[0054] The SND / A unit 11 includes a first sewage treatment chamber 111 and an oxygenating component 112 for oxygenating the first sewage treatment chamber 111, and is used to treat municipal sewage. The SND / A unit is configured to house nitrifying bacteria, nitrite-forming bacteria, denitrifying bacteria, and anaerobic ammonium-oxidizing bacteria, and treats municipal sewage through simultaneous nitrification and denitrification, short-cut nitrification and anaerobic ammonium-oxidation, and short-cut denitrification and anaerobic ammonium-oxidation reactions, thereby performing primary denitrification and forming primary treated sewage.

[0055] In other words, after the municipal sewage is passed into the SND / A unit 11, the municipal sewage undergoes simultaneous nitrification and denitrification reaction, short-cut nitrification anaerobic ammonium oxidation reaction and short-cut denitrification anaerobic ammonium oxidation reaction. The simultaneous nitrification and denitrification reaction is that nitrifying bacteria nitrify ammonia nitrogen into nitrate, and denitrifying bacteria denitrify nitrate to nitrogen gas for denitrification. The short-cut nitrification anaerobic ammonium oxidation reaction is that nitrite bacteria short-cut nitrify ammonia nitrogen into nitrite, and anaerobic ammonium oxidizing bacteria use nitrite to oxidize ammonia nitrogen to generate nitrogen gas for denitrification. The short-cut denitrification anaerobic ammonium oxidation reaction is that denitrifying bacteria denitrify nitrate to nitrite, and anaerobic ammonium oxidizing bacteria use nitrite to oxidize ammonia nitrogen to generate nitrogen gas for denitrification, thereby denitrifying and forming a treated sewage at one time; wherein, the treated sewage includes nitrogen oxides containing nitrite and nitrate and residual ammonia nitrogen.

[0056] Alternatively, the dissolved oxygen concentration in the SND / A unit 11 is preferably maintained below 0.5 mg / L. At this concentration, the denitrifying bacteria and anaerobic ammonium oxidizing bacteria can work, and the anaerobic ammonium oxidizing bacteria are autotrophic bacteria, and do not require a carbon source for anaerobic ammonium oxidation reaction and survival, thus saving a carbon source. Although the activity of the nitrite bacteria and the nitrifying bacteria is suppressed, they can still utilize dissolved oxygen to oxidize ammonia nitrogen to form nitrite and nitrate. Specifically, the nitrite bacteria include ammonia oxygen bacteria. Ammonia oxygen bacteria can utilize oxygen to oxidize ammonia nitrogen into nitrite, and the oxygen demand is relatively low during operation.

[0057] It is worth mentioning that some intermediate by-product nitric oxide will be produced in the simultaneous nitrification and denitrification reaction, the short-cut nitrification anaerobic ammonium oxidation reaction and the short-cut denitrification anaerobic ammonium oxidation reaction. Therefore, a small amount of nitric oxide dissolved in water will also exist in the SND / A unit 11. At the same time, although most anaerobic ammonium oxidizing bacteria can directly utilize nitrite to oxidize ammonia nitrogen to generate nitrogen gas, they cannot directly utilize nitric oxide to oxidize ammonia nitrogen. The anaerobic ammonium oxidizing bacteria in the SND / A unit 11 of the present disclosure include bacteria that utilize the nitrite and the nitric oxide to oxidize ammonia nitrogen, so that the nitric oxide in the sewage can be removed and the ammonia nitrogen can be further removed.

[0058] It should be noted that when the SND / A unit 11 is operating, the oxygen in the SND / A unit 11 will be consumed, and the oxygenation component 112 will be oxygenated. Oxygenation and oxygen consumption need to be relatively balanced. Therefore, the dissolved oxygen concentration in the wastewater of the SND / A unit 11 can be maintained at the above-mentioned preferred low dissolved oxygen concentration. Therefore, it is necessary to monitor and control the dissolved oxygen concentration in the wastewater of the SND / A unit 11 to ensure that the low dissolved oxygen concentration in the SND / A unit 11 can be maintained.

[0059] However, for the SND / A unit 11, although the nitrite-producing bacteria continuously consume oxygen, the oxygenating component 112 also continuously replenishes oxygen. The constant balance adjustment mechanism of air supply and consumption makes the change of the dissolved oxygen concentration in the sewage relatively gradual, and the dissolved oxygen concentration is unlikely to change significantly in a short period of time. Therefore, when the dissolved oxygen concentration is detected by the oxygen concentration detection component alone, the change in the dissolved oxygen concentration in a short period of time is usually not obvious, and it is impossible to promptly and clearly reflect whether the oxygen consumption of the SND / A unit 11 has changed. If the oxygen supply is adjusted only when the dissolved oxygen concentration changes significantly, the imbalance between oxygen supply and oxygen consumption will often last for a long time.

[0060] The oxidation-reduction potential (ORP) detector is based on electrochemical principles. When an ORP meter is inserted into sewage, oxidized and / or reduced substances on the surfaces of two electrodes undergo an oxidation-reduction reaction. The gain or loss of electrons causes the potential difference between the two electrodes to change, reflecting the concentration changes of oxidized and / or reduced substances in the sewage. Since the oxidation-reduction potential in sewage lacks a balance mechanism, when the dissolved oxygen concentration changes, the oxidation-reduction potential can change significantly in a short period of time. Therefore, under the same oxygen consumption, the oxidation-reduction potential can change significantly, thereby reflecting the oxygen consumption changes of the SND / A unit 11 more significantly in a short period of time, and can promptly and clearly reflect the oxygen consumption changes. However, since the oxidized substances in the SND / A unit 11 include not only dissolved oxygen but also oxidized substances such as nitrite, the oxidation-reduction potential changes in the SND / A unit 11 may be caused not only by oxygen consumption, but also by other oxidized or reduced substances such as nitrite. Therefore, if the oxygen concentration changes in the SND / A unit 11 are judged to have changed based solely on the oxidation-reduction potential changes, errors are prone to occur.

[0061] Therefore, in order to accurately, promptly, and clearly reflect changes in oxygen consumption and balance oxygenation and consumption in the SND / A unit 11, the SND / A unit 11 is equipped with a first oxygen concentration detector 113 and a first oxidation-reduction potential detector 114, which are immersed in the sewage. The first oxygen concentration detector 113 is used to detect the dissolved oxygen concentration in the sewage in the first sewage treatment chamber 111. The first oxidation-reduction potential detector 114 is used to detect the oxidation-reduction potential in the sewage in the first sewage treatment chamber 111. Specifically, the first oxygen concentration detector 113 is a dissolved oxygen concentration detector, and the first oxidation-reduction potential detector 114 is an oxidation-reduction potentiometer (ORP meter).

[0062] The control unit is connected to the first oxygen concentration detecting element 113 and the first oxidation-reduction potential detecting element 114, respectively. The control unit is configured to adjust the oxygenation flow rate of the first sewage treatment chamber 111 to timely balance oxygen consumption and oxygenation when the detection data of the first oxygen concentration detecting element 113 and the first oxidation-reduction potential detecting element 114 fluctuate in a positive correlation and the fluctuation amount of the detection data of the first oxidation-reduction potential detecting element 114 is outside a first predetermined range.

[0063] Specifically, when the detection data of the first oxygen concentration detector 113 and the first oxidation-reduction potential detector 114 fluctuate in a positive correlation, for example, both increase or decrease, to determine that the change in the oxidation-reduction potential in the sewage is indeed caused by a change in the dissolved oxygen concentration in the sewage, based on the fluctuation amount of the oxidation-reduction potential detected by the first oxidation-reduction potential detector 114 being outside a first predetermined range, for example, when the oxidation-reduction potential fluctuates positively and the fluctuation amount is greater than the upper limit of the first predetermined range (usually a positive value), it is determined that the oxygen consumption in the sewage is decreasing and is less than the oxygenation amount, and the oxygenation flow rate is reduced to balance the subsequent oxygenation amount and oxygen consumption. Conversely, when the oxidation-reduction potential fluctuates negatively and the fluctuation amount is less than the lower limit of the first predetermined range (usually a negative value), it is determined that the oxygen consumption in the sewage is increasing and is greater than the oxygenation amount, and the oxygenation flow rate is increased to balance the subsequent oxygenation amount and oxygen consumption.

[0064] Optionally, the oxygenating component 112 is a first aerator, which may be a first microporous membrane aerator, for using a microporous membrane as a gas diffusion medium to release air in the form of tiny bubbles into the sewage of the SND / A unit 11 through the tiny pores on the microporous membrane. The multiple tiny bubbles have a large specific surface area and a long residence time in water. The contact area for oxygen to diffuse from the bubbles to the sewage is large, and there is more time for oxygen to dissolve into the sewage, which is conducive to the efficient transfer of oxygen to the sewage.

[0065] Optionally, the SND / A unit 11 is further provided with a first stirring member 115. When the aeration volume of the first microporous membrane aerator is low and the stirring effect is average, the first stirring member 115 can be turned on to disperse oxygen, thereby facilitating the nitrification and nitration reactions. Specifically, the first stirring member 115 can be implemented as an electric or manual stirrer.

[0066] The PDA unit 12 is connected to the rear stage of the SND / A unit 11 and has a second sewage treatment chamber 121. Denitrifying bacteria and anaerobic ammonium oxidizing bacteria are arranged in the second sewage treatment chamber 121 to treat the primary treated sewage through a short-range denitrification and anaerobic ammonium oxidizing reaction to perform secondary denitrification and form secondary treated sewage.

[0067] That is to say, after the primary treated sewage is passed into the PDA unit 12, a short-range denitrification anaerobic ammonium oxidation reaction occurs in the PDA unit 12, that is, the denitrifying bacteria reduce nitrate to nitrite, and the anaerobic ammonium oxidizing bacteria use nitrite to oxidize ammonia nitrogen to generate nitrogen gas for denitrification. As a result, the PDA unit causes the nitrate to be short-range denitrified into nitrite and the nitrite to anaerobic ammonium oxidize ammonia nitrogen to form nitrogen gas, thereby secondary denitrification and forming secondary treated sewage.

[0068] The PDA unit 12 is not oxygenated, the activities of the denitrifying bacteria and the anaerobic ammonium oxidizing bacteria are relatively good, and the denitrification effect of the PDA unit 12 is relatively good.

[0069] It is worth mentioning that since the intermediate by-product nitric oxide remaining after treatment by the SND / A unit 11 will be brought into the PDA unit 12, and some intermediate by-product nitric oxide will also be produced in the PDA unit 12, the anaerobic ammonia-oxidizing bacteria in the PDA unit 12 also include bacteria that can utilize the nitrite and the nitric oxide to oxidize ammonia nitrogen.

[0070] Optionally, the PDA unit 12 is equipped with a second oxygen concentration detector 122 and a second oxidation-reduction potential detector 123 for immersion in the sewage. The second oxygen concentration detector 122 is used to detect the dissolved oxygen concentration in the sewage in the second sewage treatment chamber 121. The second oxidation-reduction potential detector 123 is used to detect the oxidation-reduction potential of the sewage in the second sewage treatment chamber 121. Specifically, the second oxygen concentration detector 122 is a dissolved oxygen concentration detector, and the second oxidation-reduction potential detector 123 is an oxidation-reduction potentiometer (ORP meter).

[0071] Since the PDA unit 12 is not provided with an oxygenation component 112, when dissolved oxygen is present in the PDA unit 12, the dissolved oxygen primarily comes from the SND / A unit 11. Therefore, if the oxygen consumption and oxygenation during treatment by the SND / A unit 11 are relatively balanced, such that the dissolved oxygen concentration and redox potential of the primary treated wastewater are relatively stable, then the dissolved oxygen concentration and redox potential of the wastewater in the PDA unit 12 should also be relatively stable. Therefore, the second oxygen concentration detector 122 and the second redox potential detector 123 can be used to assist in detecting whether the oxygen consumption and oxygenation during treatment by the SND / A unit 11 are indeed relatively balanced, and to determine the relative balance effect. Specifically, the detection data of the second oxygen concentration detector 122 and the second redox potential detector 123 fluctuate in a positive correlation, and the fluctuation amount of the detection data of the second redox potential detector 123 is stable within a second predetermined range, to determine whether the oxygen consumption and oxygenation during treatment in the first sewage treatment chamber 111 are indeed relatively balanced.

[0072] Optionally, the PDA unit 12 is further provided with a second stirring member 124. The second stirring member 124 can be activated to facilitate a relatively uniform distribution of bacteria in the PDA unit 12 throughout the wastewater, thereby facilitating the denitrification effect of the secondary denitrification. Specifically, the second stirring member 124 can be implemented as an electric / manual stirrer.

[0073] The M / SND unit 13 is connected to the rear stage of the PDA unit 12 and includes an MBR filter membrane 132 and a scrubbing aeration element 133 for aerating and scrubbing the MBR filter membrane to form treated water and activated sludge.

[0074] Thus, the MBR filter membrane 132 intercepts nitrite-reducing bacteria, nitrifying bacteria, denitrifying bacteria, anaerobic ammonium-oxidizing bacteria, and other solid impurities that escape from the SND / A unit 11 and the PDA unit 12 to the M / SND unit 13, preventing the bacteria from being lost with the treated water. Furthermore, the scrubbing aeration element 133 scrubs the MBR filter membrane 132 through aeration, causing the intercepted substances to fall off the outer surface of the MBR filter membrane 132 and fall to the bottom of the M / SND unit 13, thereby forming activated sludge, which is also coated with aerated oxygen.

[0075] Optionally, the MBR filter membrane includes a plurality of hollow membrane fibers exposed to sewage, which are used to form treated water inside the hollow membrane fibers and intercept impurities (such as bacteria) on the outer surface of the hollow membrane fibers.

[0076] Optionally, nitrifying bacteria and denitrifying bacteria are attached to the outer surface of the MBR filter membrane, and the M / SND unit 13 is used to treat the secondary treated wastewater through simultaneous nitrification and denitrification reactions and filtration. In this case, the dissolved oxygen concentration in the M / SND unit 13 is preferably maintained below 0.5 mg / L, for example, 0.1 to 0.5 mg / L. At this dissolved oxygen concentration, the denitrifying bacteria can function. Although the activity of the nitrifying bacteria is suppressed, they can still use dissolved oxygen to oxidize ammonia nitrogen to form nitrate. This allows simultaneous nitrification and denitrification reactions to occur within the M / SND unit 13, whereby nitrifying bacteria oxidize ammonia nitrogen to nitrate, and denitrifying bacteria reduce nitrate to nitrogen gas, thereby further denitrifying the wastewater and ensuring a denitrification effect. Furthermore, the low dissolved oxygen concentration in the M / SND unit 13 also helps to prevent the low dissolved oxygen environment within the SND / A unit 11 from being destroyed and to ensure low oxygen consumption for the entire device. Of course, it is understandable that when the denitrification effects of the above two units are relatively good and the sewage does not need further denitrification, the M / SND unit 13 can also be maintained above 0.5 mg / L, but the operating energy consumption will increase accordingly.

[0077] Optionally, the M / SND unit 13 further includes a housing 131. The MBR filter membrane 132 is disposed within the housing 131 to filter wastewater and provide attachment for nitrifying and denitrifying bacteria. The scrubbing aerator 133 is disposed below the MBR filter membrane 132 and is used to aerate the MBR filter membrane 132 to promote the shedding of intercepted material from the outer surface of the MBR filter membrane 132, thereby reducing the chance of activated sludge clogging the MBR filter membrane 132 and facilitating the backflow of the activated sludge. The scrubbing aerator 133 also provides oxygen for the nitrifying bacteria within the M / SND unit 13.

[0078] Optionally, the scrubbing aerator 133 is a pulse aerator, which is used to intermittently aerate large bubbles with large mechanical disturbance energy. The aeration hole diameter of the pulse aerator is larger than the aeration hole diameter of the microporous aerator, which is conducive to aeration and scrubbing of the activated sludge retained by the MBR filter membrane 132, thereby causing the activated sludge to fall off the MBR filter membrane 132. At the same time, the pulse aerator is conducive to achieving a lower air-to-water ratio during aeration, avoiding the excessively high air-to-water ratio of traditional aeration methods, thereby helping to avoid the destruction of the low dissolved oxygen concentration in the SND / A unit 11 due to the backflow of excessively high dissolved oxygen concentration in the activated sludge. Specifically, the air-to-water ratio of aeration by the scrubbing aerator 133 is below 6:1, preferably an air-to-water ratio of 3:1 or below.

[0079] It's worth noting that the conventional perforated tube continuous aeration system for MBR membrane modules typically produces an air-to-water ratio exceeding 7:1. This not only increases the power consumption of the air supply blower but also leads to excessively high dissolved oxygen concentrations in the system, which can easily disrupt the operating environment of anaerobic ammonium oxidation. The pulse aerator reduces the air-to-water ratio to below 6:1 (optimally below 3:1), significantly reducing the blower's power consumption and effectively lowering the system's dissolved oxygen concentration, creating favorable conditions for the coupling of membrane separation and anaerobic ammonium oxidation.

[0080] Optionally, a partition 1313 is provided in the housing 131 to separate a filter chamber 1312 and an oxygen supply chamber 1311 located upstream of the filter chamber 1312 and connected to the filter chamber 1312. The filter chamber 1312 accommodates the MBR filter membrane 132 and the scrubbing aerator 133, and an oxygen supply component 134 is provided in the oxygen supply chamber 1311.

[0081] Specifically, the oxygenation component 134 can be a second aerator, which is a second microporous membrane aerator. This aerator utilizes a microporous membrane as a gas diffusion medium, releasing air into the sewage in the oxygenation chamber 1311 in the form of tiny bubbles through the tiny pores of the microporous membrane. These multiple tiny bubbles have a large specific surface area and a long residence time in the water. This provides a large contact area for oxygen to diffuse from the bubbles into the sewage, allowing more time for oxygen to dissolve in the sewage. This facilitates efficient oxygen transfer to the sewage in the oxygenation chamber 1311. As a result, the supplemental oxygen from the oxygenation chamber 1311 enters the M / SND unit 13 and before filtration, allowing for more dissolved oxygen in the sewage, thereby enhancing the nitrification reaction within the M / SND unit 13.

[0082] Optionally, the M / SND unit 13 is equipped with a third oxygen concentration detector 135 and a third oxidation-reduction potential detector 136 for immersion in the sewage. The third oxygen concentration detector 135 is used to detect the dissolved oxygen concentration in the sewage within the M / SND unit 13. The third oxidation-reduction potential detector 136 is used to detect the redox potential of the sewage within the M / SND unit 13. Specifically, the third oxygen concentration detector 135 is a dissolved oxygen concentration detector, and the third oxidation-reduction potential detector 136 is an oxidation-reduction potentiometer (ORP meter).

[0083] Thus, when the detection data of the third oxygen concentration detection element 135 and the third oxidation-reduction potential detection element 136 fluctuate in a positive correlation, that is, the detection values ​​of the third oxygen concentration detection element 135 and the third oxidation-reduction potential detection element 136 both increase or decrease, to determine that the change in the oxidation-reduction potential in the sewage is indeed caused by a change in the dissolved oxygen concentration in the sewage, the oxygen consumption and oxygen supply amount in the M / SND unit 13 are determined to be relatively balanced based on whether the fluctuation amount of the oxidation-reduction potential detected by the third oxidation-reduction potential detection element 136 is within a third predetermined range. For example, when the oxidation-reduction potential fluctuates positively and the fluctuation amount is greater than the upper limit of the third predetermined range, it is determined that the dissolved oxygen concentration in the sewage is increasing, the oxygen consumption is decreasing, and is less than the oxygen supply amount, and thus the oxygen supply flow rate is reduced to balance the oxygen supply and oxygen consumption in the M / SND unit 13. On the contrary, when the redox potential fluctuates negatively and the fluctuation amount is less than the lower limit value of the third predetermined range, it is determined that the dissolved oxygen concentration in the sewage is decreasing, the oxygen consumption is increasing, and is greater than the oxygen supply amount, thereby increasing the oxygen supply flow rate in the M / SND unit 13 to balance the oxygen supply amount and the oxygen consumption in the M / SND unit 13.

[0084] The reflux unit 14 is connected to the M / SND unit 13 and the SND / A unit 11, respectively, and is used to return the activated sludge to the SND / A unit 11. Thus, through the reflux unit 14, nitrite-reducing bacteria, nitrifying bacteria, denitrifying bacteria, anaerobic ammonium-oxidizing bacteria, and oxygen are returned to the SND / A unit 11, thereby reducing the loss of bacteria in the SND / A unit 11 and the amount of oxygen supplied to the SND / A unit 11.

[0085] Optionally, when the M / SND unit 13 contains nitrifying bacteria, the nitrate formed by the nitrifying bacteria nitrifying ammonia nitrogen can also be refluxed to the SND / A unit 11, and the nitrate can be input as a reactant in the SND / A unit 11 for further reaction treatment in the SND / A unit 11.

[0086] Optionally, the reflux unit 14 includes a reflux pipe 141 and a reflux driver 142. The reflux pipe 141 is connected to the bottom of the SND / A unit 11 and the bottom of the M / SND unit 13, respectively. The reflux driver 142 is connected to the reflux pipe 141 and is used to drive reflux. Specifically, the reflux driver 142 is implemented as a first drive pump.

[0087] Therefore, since the amount of inflation required by the SND / A unit 11 and the M / SND unit 13 is small, the PDA unit 12 does not need to be inflated. The amount of inflation required when the device of the present invention is working is small, which is conducive to saving energy consumption caused by the production of oxygen. The energy consumption is low. Since the bacteria can flow back into the SND / A unit 11, the anaerobic ammonia oxidizing bacteria will not be passively lost and can treat sewage at a low water temperature of as low as 7°C. It is suitable for continuous denitrification treatment of municipal sewage in environments including normal water temperature and low water temperature in winter, and is not limited to anaerobic ammonia nitrogenization processes in areas with higher water temperatures in winter.

[0088] Optionally, the MBR membrane mainstream anaerobic ammonia oxidation treatment device suitable for municipal sewage also includes a sewage supply unit 16. The sewage supply unit 16 is respectively connected to the SND / A unit 11 and the PDA unit 12. It can be understood that conventional municipal sewage to be treated includes not only ammonia nitrogen, but also a carbon source required for the growth and metabolism of denitrifying bacteria. The present disclosure achieves full utilization of the carbon source of raw water by providing municipal sewage containing a carbon source to the PDA unit 12, which is beneficial to ensure that the denitrifying bacteria in the PDA unit 12 can grow and work without adding additional carbon sources, and the ammonia nitrogen in the municipal sewage is also anaerobic ammonia oxidized into nitrogen gas by anaerobic ammonia bacteria in the PDA unit 12 for denitrification.

[0089] The sewage supply unit 16 includes a main water supply pipe 161, a first water supply branch pipe 162, and a second water supply branch pipe 163. The first water supply branch pipe 162 is connected to the main water supply pipe 161 and the first sewage treatment chamber 111, thereby directing raw sewage from the main water supply pipe 161 to the first sewage treatment chamber 111. The second water supply branch pipe 163 is connected to the main water supply pipe 161 and the second sewage treatment chamber 121, and is located after the first water supply branch pipe 162, thereby directing raw sewage from the main water supply pipe 161 to the second sewage treatment chamber 121.

[0090] Optionally, a first water supply valve 1621 and a second water supply valve 1631 are respectively provided on the first water supply branch pipe 162 and the second water supply branch pipe 163. Thus, by adjusting the openings of the first water supply valve 1621 and the second water supply valve 1631, the distribution ratio of raw water and sewage between the SND / A unit 11 and the PDA unit 12 can be adaptively adjusted. For example, if it is observed that the survival of denitrifying bacteria in the PDA unit 12 is poor, the opening of the second water supply valve 1631 can be increased to ensure that the denitrifying bacteria in the PDA unit 12 are provided with a relatively sufficient carbon source.

[0091] Optionally, the MBR membrane-based mainstream anaerobic ammonium oxidation treatment device for municipal sewage further includes an air supply unit 15. The air supply unit 15 includes a first air supply pipe 151. The first air supply pipe 151 is connected to the oxygenating component 112 for supplying air to the oxygenating component 112.

[0092] Optionally, the air supply unit 15 further includes a first air supply valve 1511. The first air supply valve 1511 is provided in the first air supply pipe 151 and is connected to the control unit, and is configured to adjust its opening under the control of the control unit, thereby regulating the oxygenation flow of the oxygenation component 112.

[0093] Optionally, the gas supply unit 15 further includes a second gas supply pipeline 152. The second gas supply pipeline 152 is connected to the oxygen supply component 134 and is used to supply gas to the oxygen supply component 134.

[0094] Optionally, the air supply unit 15 further includes a second air supply valve 1521 . The second air supply valve 1521 is provided in the second air supply pipe 152 and is connected to the control unit, and is configured to adjust its opening under the control of the control unit, thereby regulating the oxygen supply flow of the oxygen supply component 134 .

[0095] Optionally, the air supply unit 15 further includes a first air supply driver 153. The first air supply driver 153 is connected to the first air supply pipe 151 and the second air supply pipe 152, respectively, and is configured to compress and drive air to be delivered to the first air supply pipe 151 and the second air supply pipe 152. Specifically, the first air supply driver 153 is a first blower.

[0096] Optionally, the air supply unit 15 further includes a third air supply pipe 154 and a second air supply drive 155. The third air supply pipe 154 is connected to the scrubbing aeration element 133. The second air supply drive 155 is connected to the third air supply pipe 154 and is configured to compress and drive air to be delivered to the third air supply pipe 154. Specifically, the second air supply drive 155 is implemented as a second blower.

[0097] Optionally, the MBR membrane mainstream anaerobic ammonium oxidation treatment device for municipal sewage further includes a water outlet unit 17. The water outlet unit 17 is connected to the water outlet of the MBR filter membrane 132 for discharging treated water.

[0098] Optionally, the water outlet unit 17 includes a water outlet pipe 171 and a water outlet drive 172. The water outlet pipe 171 is connected to the water outlet of the MBR filter membrane 132. The water outlet drive 172 is connected to the water outlet pipe 171 and is used to drive the treated water out of the water outlet pipe 171. Specifically, the water outlet drive 172 is a second drive pump.

[0099] Figure 2 This is a flow chart of the MBR membrane mainstream anaerobic ammonium oxidation treatment method applicable to municipal sewage according to the embodiment of the present disclosure. Figure 1 and Figure 2 The present disclosure also provides a MBR membrane mainstream anaerobic ammonium oxidation treatment method applicable to municipal sewage, comprising the following steps:

[0100] S10: Pass the municipal sewage into the oxygenated SND / A unit 11, wherein the SND / A unit 11 includes nitrite bacteria, nitrifying bacteria, denitrifying bacteria and anaerobic ammonium oxidation bacteria to treat the municipal sewage through simultaneous nitrification and denitrification reaction, short-cut nitrification and anaerobic ammonium oxidation reaction and short-cut denitrification and anaerobic ammonium oxidation reaction. The simultaneous nitrification and denitrification reaction is that the nitrifying bacteria nitrifies the ammonia nitrogen into nitrate, and the denitrifying bacteria denitrifies the nitrate into nitrogen gas for denitrification, and the short-cut nitrification and denitrification reaction is that the nitrifying bacteria nitrifies the ammonia nitrogen into nitrate, and the denitrifying bacteria denitrifies the nitrate into nitrogen gas for denitrification, and the short-cut nitrification and denitrification reaction is that the nitrite ... The anaerobic ammonium oxidation reaction is that nitrite-reducing bacteria nitrifies ammonia nitrogen into nitrite, and anaerobic ammonium-oxidizing bacteria use nitrite to oxidize ammonia nitrogen to generate nitrogen gas for denitrification. The short-cut denitrification anaerobic ammonium oxidation reaction is that denitrifying bacteria reduce nitrate to nitrite through short-cut denitrification, and anaerobic ammonium-oxidizing bacteria use nitrite to oxidize ammonia nitrogen to generate nitrogen gas for denitrification, so as to denitrify and form a single treated sewage; wherein, the single treated sewage includes nitrogen oxides containing nitrite and nitrate and residual ammonia nitrogen.

[0101] Optionally, the nitrogen oxides in the primary treated sewage also include nitric oxide. The nitrite-transforming bacteria include ammonia-oxidizing bacteria, and the anaerobic ammonia-oxidizing bacteria include bacteria that can directly utilize nitrite and nitric oxide to oxidize ammonia nitrogen.

[0102] Optionally, in the SND / A unit 11 , the dissolved oxygen concentration is 0.02 mg / L to 0.5 mg / L, the activated sludge concentration is 2500 mg / L to 15000 mg / L, and the gas-water ratio is 0.5 to 2.0:1 (based on a water depth of 6 m).

[0103] S20: The primary treated sewage is passed into the unoxygenated PDA unit 12, which includes denitrifying bacteria and anaerobic ammonium oxidizing bacteria to treat the primary treated sewage through a short-range denitrification anaerobic ammonium oxidizing reaction, that is, the denitrifying bacteria reduce nitrate to nitrite, and the anaerobic ammonium oxidizing bacteria utilizes nitrite to oxidize ammonia nitrogen to generate nitrogen gas for secondary denitrification and form secondary treated sewage.

[0104] Optionally, the anaerobic ammonium-oxidizing bacteria include bacteria that can directly utilize nitrite and nitric oxide to oxidize ammonia nitrogen.

[0105] S30: passing the secondary treated sewage into the M / SND unit 13, wherein the M / SND unit includes an MBR filter membrane 132 and a scrubbing aeration element 133 corresponding to the MBR filter membrane 132, so as to form treated water and activated sludge.

[0106] Optionally, the M / SND unit 13 further comprises nitrifying bacteria and denitrifying bacteria, the dissolved oxygen concentration is 0.1 mg / L-0.5 mg / L, the activated sludge concentration is 3000 mg / L-30000 mg / L, and the air-water ratio of the scrubbing aerator 133 is less than 6:1 (based on a water depth of 3.5 m).

[0107] S40 : The activated sludge in the M / SND unit 13 is returned to the SND / A unit 11 through the return unit 14 .

[0108] Optionally, the reflux ratio of the reflux unit 14 is 30% to 600%, and it is worth mentioning that the current reflux ratio of the reflux unit 14 is negatively correlated with the current dissolved oxygen concentration in the SND / A unit 11. That is, at the same current moment, when the dissolved oxygen concentration in the SND / A unit 11 is set to be relatively low, the reflux ratio of the reflux unit 14 is set to be relatively high, so that relatively more oxygen and nitrate can be replenished in the SND / A unit 11 through reflux for bacterial reaction in the SND / A unit 11. Correspondingly, at the same current moment, when the dissolved oxygen concentration in the SND / A unit 11 is set to be relatively high, the reflux ratio of the reflux unit 14 is set to be relatively low, so that relatively less oxygen and nitrate can be replenished in the SND / A unit 11 through reflux for reaction, which is beneficial to ensuring the denitrification effect of the SND / A unit 11 and full utilization of oxygen.

[0109] Optionally, S10 further includes the following steps: based on the positive correlation between the dissolved oxygen concentration of the sewage in the SND / A unit 11 and the redox potential, and the fluctuation amount of the redox potential being outside a first preset range, adjusting the oxygen flow rate to balance the oxygen supply and oxygen consumption in the SND / A unit 11. This allows the oxygen supply and oxygen consumption of the SND / A unit 11 to be relatively balanced when the unit is operating, which helps to keep the dissolved oxygen in the SND / A unit 11 within a relatively low concentration range.

[0110] Optionally, S20 further includes the following step: when the dissolved oxygen concentration of the sewage in the PDA unit 12 fluctuates in a positive correlation with the redox potential, based on whether the fluctuation amount of the redox potential is within a second preset range, assisting in determining whether the oxygen consumption and oxygen supply of the SND / A unit 11 are balanced. This facilitates assisting in determining the balance between oxygen supply and consumption in the SND / A unit 11.

[0111] Optionally, S30 further includes the following step: based on the fact that the dissolved oxygen concentration of the sewage in the M / SND unit 13 fluctuates in a positive correlation with the redox potential, and the fluctuation amount of the redox potential is outside a third preset range, adjusting the oxygen supply flow rate of the M / SND unit 13 to balance the oxygen consumption and oxygen supply amount of the nitrification reaction in the M / SND unit 13. Thus, when the M / SND unit 13 is operating, the oxygen supply and oxygen consumption can be relatively balanced, which is conducive to the sufficient dissolved oxygen in the M / SND unit 13 for the nitrification reaction of the nitrifying bacteria.

[0112] Optionally, the MBR membrane mainstream anaerobic ammonia oxidation treatment method suitable for municipal sewage further includes the following steps: when treating the municipal sewage, part of the municipal sewage is directly introduced into the SND / A unit 11, and part is directly introduced into the PDA unit 12. Specifically, when supplying sewage, according to the flow meter, the flow ratio of the sewage allocated to the SND / A unit 11 is 50-95%, and the flow ratio of the sewage allocated to the PDA unit 12 is 5-50%. In other words, the raw sewage is mainly directly introduced into the SND / A unit 11, and a small part of the raw sewage is considered to be directly introduced into the PDA unit 12. This is beneficial to ensure the carbon source required for the work and survival of the denitrifying bacteria in the PDA unit 12 without adding additional carbon sources.

[0113] The following describes in detail the processing steps of a specific embodiment of the present disclosure:

[0114] 1) A two-point water inlet method is adopted, with raw water and sewage entering the SND / A unit 11 and the PDA unit 12 respectively. The flow rate of sewage allocated to the SND / A unit 11 is 50-95% of the total flow rate, and the flow rate of sewage allocated to the PDA unit 12 is 5-50%.

[0115] 2) Raw sewage is passed into the SND / A unit 11 for primary denitrification in the SND / A unit 11 to form primary treated sewage. The SND / A unit 11 includes nitrifying bacteria, ammonia-oxidizing bacteria, denitrifying bacteria, and anaerobic ammonium-oxidizing bacteria, with the anaerobic ammonium-oxidizing bacteria including bacteria that can utilize nitrite and nitric oxide to oxidize ammonia nitrogen. The dissolved oxygen concentration in the SND / A unit 11 is 0.02-0.5 mg / L, the activated sludge concentration is 2500-15000 mg / L, and the aeration air-water ratio is 0.5-2.0:1 (based on a water depth of 6 m).

[0116] 3) The effluent from the SND / A unit 11 enters the PDA unit 12, and a portion of the raw sewage also enters the PDA unit 12 to undergo secondary denitrification in the SND / A unit 11 and form secondary treated sewage; wherein the PDA unit 12 is not oxygenated, and the anaerobic ammonium oxidation unit includes denitrifying bacteria and anaerobic ammonium oxidizing bacteria, and the anaerobic ammonium oxidizing bacteria include bacteria that can utilize nitrite and nitric oxide to oxidize ammonia nitrogen.

[0117] 4) The effluent from PDA unit 12 enters M / SND unit 13, where it filters the secondary treated wastewater to form treated water and activated sludge. M / SND unit 13 contains nitrifying and denitrifying bacteria. The dissolved oxygen concentration in M / SND unit 13 is 0.1-0.5 mg / L, the activated sludge concentration is 3,000-30,000 mg / L, and the air-to-water ratio of the scrubbing aerator 133 is less than 6:1 (based on a water depth of 3.5 meters).

[0118] 5) The bottom of the M / SND unit 13 is pumped back to the SND / A unit 11 , wherein the backflow ratio of the backflow flow to the inflow flow of the raw water sewage in step 1) is 30% to 600%.

[0119] Therefore, taking a processing scale of 10000m 3 / d of municipal sewage treatment plant grit tank effluent was taken as the treatment object, and the denitrification performance of the above specific system was investigated. The specific water quality during operation was as follows: influent CODcr concentration was 60~280mg / L, influent ammonia nitrogen concentration was 30~50mg / L, influent total nitrogen concentration was 40~60mg / L, the influent was municipal sewage with low ammonia nitrogen (ammonia nitrogen concentration ≤60mg / L), and the water temperature could be as low as 7℃.

[0120] After the system runs stably, the outlet CODcr concentration is 10~20mg / L, the outlet ammonia nitrogen concentration is ≤1mg / L, and the outlet total nitrogen concentration is ≤5mg / L. It can effectively reduce the ammonia nitrogen concentration with low power consumption and low energy consumption.

[0121] And for other treatment routes of ammonia nitrogen wastewater treatment as a comparison, in some examples, the first treatment route in the related art includes A 2 O process, secondary sedimentation tank and deep treatment unit. Among them, A 2 The O process includes an anaerobic unit, an anoxic unit, and a nitrification unit. Because the nitrification unit must convert all ammonia nitrogen in the influent to nitrate, it requires a high dissolved oxygen concentration and a high gas-water ratio. This results in high oxygen demand, high energy consumption, a long process flow, and high construction costs. In contrast, the treatment device and method disclosed herein can save over 60% of electricity consumption per ton of water.

[0122] In other examples, the second treatment route in related art includes a nitrification unit, an anaerobic ammonium oxidation unit, a secondary sedimentation tank, and an advanced treatment unit. The nitrification unit requires a relatively high gas-to-water ratio and dissolved oxygen concentration, for example, 0.5 mg / L to 1 mg / L. This results in relatively high energy consumption, a long process flow, and high construction costs. In contrast, the treatment device and method disclosed herein can save over 20% of electricity consumption per ton of water.

[0123] Therefore, the present disclosure can save energy compared with the above-mentioned related technical routes.

[0124] The above embodiments are merely illustrative of the principles and effects of this disclosure and are not intended to limit this disclosure. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of this disclosure. Therefore, any equivalent modifications or alterations made by a person skilled in the art without departing from the spirit and technical concepts disclosed herein shall be encompassed by the scope of protection of this disclosure.

Claims

1. MBR membrane mainstream anaerobic ammonium oxidation treatment device suitable for municipal sewage, characterized by: include: The SND / A unit comprises a first sewage treatment chamber and an oxygenating component for supplying oxygen to the first sewage treatment chamber, and is used for simultaneous nitrification and denitrification, short-cut nitrification and anaerobic ammonium oxidation, and short-cut denitrification and anaerobic ammonium oxidation to treat municipal sewage, thereby nitrifying ammonia nitrogen into nitrate and denitrifying nitrate into nitrogen gas for denitrification, short-cut nitrification of ammonia nitrogen into nitrite and anaerobic ammonium oxidation reaction of nitrite and ammonia nitrogen to denitrification, and short-cut denitrification of nitrite into nitrite and anaerobic ammonium oxidation reaction of nitrite and ammonia nitrogen to denitrification, thereby performing one-step denitrification and forming one-step treated sewage; The PDA unit is connected to the rear stage of the SND / A unit to treat the primary treated wastewater with a short-cut denitrification anaerobic ammonium oxidation reaction, so that nitrate is short-cut denitrified into nitrite and nitrite reacts with ammonia nitrogen to form nitrogen gas for secondary denitrification and to form secondary treated wastewater; An M / SND unit is connected to the rear stage of the PDA unit and includes an MBR filter membrane and a scrubbing aeration member for aerating and scrubbing the MBR filter membrane, for filtering and treating the secondary treated wastewater to form treated water and activated sludge; as well as The return unit is used to connect the M / SND unit and the SND / A unit so as to return the activated sludge to the SND / A unit.

2. The MBR membrane mainstream anaerobic ammonium oxidation treatment device suitable for municipal sewage according to claim 1, characterized in that: In the simultaneous nitrification and denitrification reaction, the short-cut nitrification anaerobic ammonium oxidation reaction and the short-cut denitrification anaerobic ammonium oxidation reaction, nitric oxide is also generated as a byproduct; The anaerobic ammonium oxidizing bacteria in the SND / A unit and / or PDA unit include bacteria that can utilize nitrite and nitric oxide to oxidize ammonia nitrogen.

3. The MBR membrane mainstream anaerobic ammonium oxidation treatment device suitable for municipal sewage according to claim 1, characterized in that: Also includes: The sewage supply unit is connected to the SND / A unit and the PDA unit respectively.

4. The MBR membrane mainstream anaerobic ammonium oxidation treatment device suitable for municipal sewage according to claim 1, characterized in that: The SND / A unit is provided with a first oxygen concentration detection element and a first oxidation-reduction potential detection element; The MBR membrane mainstream anaerobic ammonium oxidation treatment device suitable for municipal sewage further includes: a control unit, connected to the first oxygen concentration detection element and the first oxidation-reduction potential detection element, respectively, for adjusting the oxygenation flow rate of the oxygenation component to balance the oxygen consumption and oxygenation amount of the SND / A unit based on the positive correlation fluctuation of the detection data of the first oxygen concentration detection element and the first oxidation-reduction potential detection element, and the fluctuation amount of the detection data of the first oxidation-reduction potential detection element being outside a first preset range; and / or The PDA unit is provided with a second oxygen concentration detection element and a second oxidation-reduction potential detection element, which are used to assist in determining whether the oxygen consumption and oxygen supply of the SND / A unit are balanced based on whether the detection data of the second oxygen concentration detection element and the second oxidation-reduction potential detection element are within a second preset range when the detection data of the second oxygen concentration detection element and the second oxidation-reduction potential detection element fluctuate in a positive correlation.

5. The MBR membrane mainstream anaerobic ammonium oxidation treatment device suitable for municipal sewage according to claim 1, characterized in that: The M / SND unit is provided with an oxygen supply component located in front of its MBR filter membrane, and the M / SND unit is provided with a third oxygen concentration detection component and a third redox potential detection component; The MBR membrane mainstream anaerobic ammonia oxidation treatment device suitable for municipal sewage also includes: a control unit, which is respectively connected to the third oxygen concentration detection element and the third oxidation-reduction potential detection element, and is used to adjust the oxygen supply flow rate of the oxygen supply component to balance the oxygen consumption and oxygen supply amount of the M / SND unit according to the positive correlation fluctuation of the detection data of the third oxygen concentration detection element and the third oxidation-reduction potential detection element, and the fluctuation amount of the detection data of the third oxidation-reduction potential detection element is outside a third preset range.

6. The MBR membrane mainstream anaerobic ammonium oxidation treatment device suitable for municipal sewage according to claim 1, characterized in that: The M / SND unit also provides simultaneous nitrification and denitrification reaction to treat the secondary treated wastewater, so that ammonia nitrogen is nitrified into nitrate and nitrate is denitrified into nitrogen gas for denitrification.

7. MBR membrane mainstream anaerobic ammonium oxidation treatment method suitable for municipal sewage, characterized by: include: Passing municipal sewage into an oxygenated SND / A unit, wherein the SND / A unit is used for simultaneous nitrification and denitrification reaction, short-cut nitrification anaerobic ammonium oxidation reaction and short-cut denitrification anaerobic ammonium oxidation reaction to treat municipal sewage, so as to nitrify ammonia nitrogen into nitrate and denitrify nitrate into nitrogen gas for denitrification, short-cut nitrification of ammonia nitrogen into nitrite and anaerobic ammonium oxidation reaction of nitrite and ammonia nitrogen into nitrogen gas for denitrification, and short-cut denitrification of nitrate into nitrite and anaerobic ammonium oxidation reaction of nitrite and ammonia nitrogen into nitrogen gas for denitrification, thereby performing one-step denitrification and forming one-step treated sewage; Passing the primary treated sewage into an unoxygenated PDA unit, wherein the PDA unit provides a short-cut denitrification anaerobic ammonium oxidation reaction to treat the primary treated sewage, so that nitrate is short-cut denitrified into nitrite and the nitrite reacts with ammonia nitrogen to form nitrogen gas for secondary denitrification and to form secondary treated sewage; Passing the secondary treated sewage into an M / SND unit, wherein the M / SND unit includes an MBR filter membrane and a scrubbing aeration element for aerating and scrubbing the MBR filter membrane to form treated water and activated sludge; and The activated sludge of the M / SND unit is returned to the SND / A unit through a return unit.

8. The MBR membrane mainstream anaerobic ammonium oxidation treatment method for municipal sewage according to claim 7, characterized in that: In the simultaneous nitrification and denitrification reaction, the short-cut nitrification anaerobic ammonium oxidation reaction and the short-cut denitrification anaerobic ammonium oxidation reaction, nitric oxide is also generated as a byproduct; the anaerobic ammonium-oxidizing bacteria in the SND / A unit and / or the PDA unit include bacteria that can utilize nitrite and nitric oxide to oxidize ammonia nitrogen; and / or The current reflux ratio of the reflux unit is negatively correlated with the current dissolved oxygen concentration in the SND / A unit; and / or In the M / SND unit, the secondary treated wastewater is also treated by simultaneous nitrification and denitrification reactions, so that ammonia nitrogen is nitrified into nitrate and nitrate is denitrified into nitrogen gas for denitrification; and / or When the municipal sewage is introduced, part of the municipal sewage is directly introduced into the SND / A unit, and part of the municipal sewage is directly introduced into the PDA unit.

9. The MBR membrane mainstream anaerobic ammonium oxidation treatment method for municipal sewage according to claim 7, characterized in that: Based on the positive correlation between the dissolved oxygen concentration and the redox potential in the SND / A unit, and the fluctuation amount of the redox potential being outside a first predetermined range, adjusting the oxygen flow rate to balance the oxygen supply and oxygen consumption in the SND / A unit; and / or; When the dissolved oxygen concentration in the PDA unit fluctuates in a positive correlation with the redox potential, assisting in determining whether the oxygen consumption and oxygen supply of the SND / A unit are balanced based on whether the fluctuation amount of the redox potential is within a second preset range; and / or; Based on the fact that the dissolved oxygen concentration in the M / SND unit fluctuates in a positive correlation with the redox potential, and the fluctuation amount of the redox potential is outside a third preset range, the oxygen supplement flow rate of the M / SND unit is adjusted to balance the oxygen consumption and oxygen supplement amount of the nitrification reaction in the M / SND unit.

10. The MBR membrane mainstream anaerobic ammonium oxidation treatment method applicable to municipal sewage according to claim 7, characterized in that: In the SND / A unit, the dissolved oxygen concentration is 0.02-0.5 mg / L, the activated sludge concentration is 2500-15000 mg / L, and the gas-water ratio is 0.5-2.0:1; and / or In the M / SND unit, the dissolved oxygen concentration is 0.1-0.5 mg / L, the activated sludge concentration is 3000-30000 mg / L, and the air-water ratio of the scrubbing aeration element is less than 6:1.

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