Membrane aeration biofilm reactor for treating aerospace wastewater

Abstract

The present invention provides a membrane aeration biofilm reactor capable of treating aerospace wastewater, which belongs to the technical field of sewage treatment equipment and includes a reactor body; an upper cover flange is provided on the top of the reactor body, and a ventilation flange is provided on the bottom of the reactor body; a pressure detection port and a vent are provided on the upper cover flange; a plurality of membrane assemblies are provided in the internal space of the reactor body, and the membrane assemblies are connected between the upper cover flange and the ventilation flange; a water inlet is provided at the bottom of the reactor body, and a water outlet and a secondary water outlet are provided at the top of the reactor body. The present invention is easily adapted to highly integrated environmental control and life protection, has low economic cost, strong resistance to environmental interference, and is reusable; the use of ventilation flanges of different structures can create a variety of redox environments of different degrees inside the MABR reactor, set different operating modes for different influent water qualities, and have higher flexibility; and can transport the gas inside the reactor to the next gas-liquid separation unit to the greatest extent.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment equipment, and in particular to a membrane aeration biofilm reactor capable of treating aerospace wastewater. Background Art

[0002] Membrane bioreactors (MBRs) feature a small footprint, high solid-liquid separation efficiency, resistance to shock loads, and ease of automated control. They are suitable for environmental control and life support systems (ECLSS) environments, where space is limited and automation requirements are high. The membrane aerated biofilm reactor (MABR) is a novel, highly efficient wastewater treatment technology that organically combines membrane aeration and biological treatment technologies. It is a type of membrane bioreactor. MABR technology is widely used in the treatment of black and odorous water bodies. It achieves high COD and ammonia nitrogen removal rates and can save over 50% of energy compared to traditional biological treatment oxygen supply methods. The MABR process can also be applied to the treatment of municipal wastewater and special industrial wastewater. However, due to the MABR's greater flexibility, process control becomes more complex, making scale-up more difficult and limiting its widespread application. Currently, the pollutant degradation mechanisms of MABR processes for small-scale water treatment primarily focus on membrane preparation, mass transfer processes, and biofilm population distribution.

[0003] The main components of wastewater generated on the International Space Station (ISS) include condensate from cooling and dehumidification, domestic wastewater, and astronaut urine. Existing wastewater treatment processes on the ISS primarily rely on physical and chemical methods. While these technologies offer high treatment efficiency, they also consume a lot of energy and materials. Microbial-based biological wastewater treatment technologies, however, offer advantages such as environmental friendliness, low energy consumption, minimal consumption of exogenous substances, and relatively high water recovery rates. These technologies are considered the future direction of wastewater treatment in regenerative life support systems. Integrated devices based on the MABR process, a microbial treatment technology, are well-suited for the confined environment of space. Therefore, designing a MABR reactor specifically for the degradation of space wastewater is feasible. Furthermore, MABR reactor design is designed for use in the microgravity environment of the space station, where surface tension plays a dominant role. Without hydrostatic pressure, gravity-driven convection, and sedimentation, directional flow and separation of liquids are difficult. Therefore, conventional MABR reactor designs struggle to achieve the desired results in the gas-liquid two-phase flow environment of space. Summary of the Invention

[0004] The purpose of the present invention is to provide a membrane aerated biofilm reactor that can treat aerospace wastewater by optimizing the structure and operating procedures, thereby enhancing the biochemical action of the MABR reactor, improving the synergy between the flow field and liquid circulation and gas-liquid separation, and thus improving the mass transfer effect of the MABR, so as to solve at least one technical problem existing in the above-mentioned background technology.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention provides a membrane aeration biofilm reactor capable of treating aerospace wastewater, comprising:

[0007] Reactor body;

[0008] The top of the reactor body is provided with an upper cover flange, and the bottom of the reactor body is provided with a ventilation flange; the upper cover flange is provided with a pressure detection port and a vent; a plurality of membrane assemblies are provided in the internal space of the reactor body, and the membrane assemblies are connected between the upper cover flange and the ventilation flange;

[0009] The bottom of the reactor body is provided with a water inlet, and the upper part of the reactor body is provided with a water outlet and a secondary water outlet.

[0010] Optionally, an inspection hole is provided on the reactor body, and an inspection hole flange is connected to the inspection hole.

[0011] Optionally, a top flange is provided on the top of the reactor body, and the upper cover flange is connected to the top flange by bolts; a bottom flange is provided on the bottom of the reactor body, and the ventilation flange is connected to the bottom flange by bolts.

[0012] Optionally, the membrane assembly includes a connection port and hollow fiber membrane filaments.

[0013] Optionally, the membrane assembly has a membrane fiber filling ratio of 150 to 225 m 2 / m 3 .

[0014] Optionally, the number of the membrane components is 6.

[0015] Optionally, the ventilation flange includes a flange plate, an annular boss is provided on the flange plate, and a partition bar is provided inside the annular boss to separate the interior of the annular boss; the flange plate is provided with connecting holes, the connecting holes are located inside the annular boss and are evenly distributed on both sides of the partition bar.

[0016] Optionally, the spacer is provided with an opening for connecting the two parts in the annular boss.

[0017] Optionally, a pressure detection port connection port is provided in the middle of the upper cover flange, and a vent interface is provided around the pressure detection port connection port.

[0018] Optionally, one end of the membrane assembly is connected to the vent interface, and the other end of the membrane assembly is connected to the connection hole.

[0019] Beneficial effects of the present invention:

[0020] (1) From the perspective of improving the flow field, the flow pattern of fluids in the special microgravity environment of the space station is different from that in the surface gravity environment, which greatly affects the design and operation of aerospace engineering systems. CFD can overcome the shortcomings of ground experiments in microgravity environments, such as short duration, simplified pure numerical calculations and many assumptions. It has strong predictive capabilities and can quickly and intuitively modify and improve the MABR reactor structure.

[0021] (2) From the perspective of structural design, the bottom ventilation structure design can adjust the redox environment inside the reactor, adopt different ventilation forms for different influent water qualities, enhance the biochemical effect of the reactor, and obtain a higher simultaneous nitrification and denitrification efficiency (SND).

[0022] (3) The MABR reactor designed based on the present invention can be applied to aerospace environments and can be used to treat condensed water, domestic wastewater, crew urine, or mixed wastewater generated by cooling and dehumidification in aerospace environments.

[0023] Additional aspects and advantages of the present invention will be set forth in part in the following description, will become apparent from the following description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 This is a three-dimensional structural diagram of a membrane aeration biofilm reactor capable of treating aerospace wastewater according to an embodiment of the present invention.

[0026] Figure 2 This is a longitudinal cross-sectional structural diagram of a membrane aeration biofilm reactor capable of treating aerospace wastewater according to an embodiment of the present invention.

[0027] Figure 3 This is a transverse cross-sectional structural diagram of a membrane aeration biofilm reactor capable of treating aerospace wastewater according to an embodiment of the present invention.

[0028] Figure 4 This is a schematic diagram of the upper cover flange structure of the membrane aeration biofilm reactor capable of treating aerospace wastewater according to an embodiment of the present invention.

[0029] Figure 5 This is a schematic diagram of the ventilation flange structure with holes in the ventilation component of the membrane aeration biofilm reactor that can treat aerospace wastewater according to an embodiment of the present invention.

[0030] Figure 6 This is a schematic diagram of the ventilation flange structure without holes in the exchanger component of the membrane aeration biofilm reactor capable of treating aerospace wastewater according to an embodiment of the present invention.

[0031] Figure 7 This is a schematic diagram of the membrane assembly structure of a membrane aeration biofilm reactor capable of treating aerospace wastewater according to an embodiment of the present invention.

[0032] Figure 8 This is a cloud diagram of the internal gas-liquid two-phase structure of a membrane aerated biofilm reactor (MABR) in a microgravity environment capable of treating space wastewater according to an embodiment of the present invention when the single-side water outlet is open.

[0033] Figure 9 This is a cloud diagram of the internal gas-liquid two-phase structure of the membrane aerated biofilm reactor (MABR) in a microgravity environment capable of treating space wastewater according to an embodiment of the present invention when the water outlets on both sides are opened.

[0034] Figure 10 This is the degradation of organic matter (COD) during the biofilm formation stage described in the embodiments of the present invention (test water temperature 29±2°C).

[0035] Figure 11 The nitrogen (NH3 - -N, NO2 - -N, NO3 - -N) degradation (test water temperature 29±2℃).

[0036] Among them: 1-reactor body; 2-upper cover flange; 3-ventilation flange; 4-pressure detection port; 5-vent; 6-membrane assembly; 7-water inlet; 8-water outlet; 9-auxiliary water outlet; 10-inspection hole; 11-inspection hole flange; 12-top flange; 13-bottom flange; 14-pressure detection port connection port; 15-vent connection port; 16-flange; 17-annular boss; 18-spacer; 19-connection hole; 20-opening; 21-connection port; 22-hollow fiber membrane. DETAILED DESCRIPTION

[0037] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention and are not to be construed as limiting the present invention.

[0038] Those skilled in the art will understand that unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art to which this invention belongs.

[0039] It should also be understood that terms, such as those defined in commonly used dictionaries, should be understood to have a meaning consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless as defined herein.

[0040] Those skilled in the art will appreciate that, unless otherwise stated, the singular forms "a," "an," "said," and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present invention refers to the presence of the stated features, integers, steps, operations, elements, and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, and / or groups thereof.

[0041] In the description of this specification, reference to the terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and integrate different embodiments or examples described in this specification, as well as features of different embodiments or examples, unless otherwise inconsistent.

[0042] In the description of this specification, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0043] In the description of this specification, the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings. They are only for the convenience of describing the present technology and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, they should not be understood as limiting the present technology.

[0044] Unless otherwise specified or limited, the terms "installed," "connected," "connected," and "disposed" should be understood broadly. For example, they may refer to fixed connection or disposition, detachable connection or disposition, or integral connection or disposition. Those skilled in the art will understand the specific meanings of these terms in this technology based on specific circumstances.

[0045] To facilitate understanding of the present invention, the present invention is further explained below with reference to specific embodiments in conjunction with the accompanying drawings. However, the specific embodiments do not constitute a limitation on the embodiments of the present invention.

[0046] Those skilled in the art should understand that the drawings are merely schematic diagrams of embodiments, and the components in the drawings are not necessarily necessary for implementing the present invention.

[0047] Example 1

[0048] like Figures 1 to 7 As shown, in this embodiment 1, a membrane aeration biofilm reactor capable of treating aerospace wastewater is provided, the structure of which includes: a reactor body 1; a cover flange 2 is provided at the top of the reactor body 1, and a ventilation flange 3 is provided at the bottom of the reactor body 1; a pressure detection port 4 and a vent 5 are provided on the cover flange 2; a plurality of membrane assemblies 6 are provided in the interior space of the reactor body 1, and the membrane assemblies 6 are connected between the cover flange 2 and the ventilation flange 3; a water inlet 7 is provided at the bottom of the reactor body 1, and a water outlet 8 and a secondary water outlet 9 are provided at the top of the reactor body 1. The reactor body 1 is provided with an inspection hole 10, and an inspection hole flange 11 is connected to the inspection hole 10.

[0049] The top of the reactor body 1 is provided with a top flange 12, and the upper cover flange 2 is connected to the top flange 12 by bolts; the bottom of the reactor body is provided with a bottom flange 13, and the ventilation flange 3 is connected to the bottom flange 13 by bolts.

[0050] The membrane assembly includes connection ports 21 provided at both ends and a hollow fiber membrane filament 22 located between the two connection ports 21 .

[0051] One structural form of the ventilation flange is: the ventilation flange includes a flange plate 16, an annular boss 17 is provided on the flange plate 16, and a partition bar 18 is provided inside the annular boss 17 to separate the interior of the annular boss 17; the flange plate 16 is provided with connecting holes 19, and the connecting holes 19 are located inside the annular boss 17 and are evenly distributed on both sides of the partition bar 18.

[0052] One structural form of the ventilation flange is that an opening 20 is provided on the spacer bar 18 to connect the two parts in the annular boss 17 .

[0053] A pressure detection port connection port 14 is provided in the middle of the upper cover flange 2 , and a vent port 15 is provided around the pressure detection port connection port 14 . One end of the membrane assembly 6 is connected to the vent port 15 , and the other end of the membrane assembly 6 is connected to the connection hole 19 .

[0054] In this embodiment 1, the membrane fiber filling ratio of the membrane assembly is 150-225m 2 / m 3 The number of membrane assemblies is 6. The number of vent interfaces 15 and connection holes 19 corresponds to the number of membrane assemblies. In actual use, those skilled in the art can set a suitable number of membrane assemblies and a suitable membrane filament filling ratio according to actual conditions.

[0055] Example 2

[0056] In this Example 2, a MABR reactor capable of treating aerospace wastewater is provided. By rationally designing the internal structure of the reactor, strengthening the biochemical action of the MABR reactor, and improving the synergy between the flow field and liquid circulation and gas-liquid separation, the mass transfer effect of the MABR reactor is improved, so as to achieve the goal of efficient treatment of aerospace wastewater.

[0057] The MABR reactor capable of treating aerospace wastewater described in Example 2 includes a reactor body 1, an air inlet / outlet (i.e., an air vent 5), a water inlet 7, a water outlet 8, an auxiliary water outlet 9, an inspection hole flange 11, an upper cover flange 2, a ventilation flange 3, a membrane assembly 6, and fixing bolt components.

[0058] Among them, the reactor body 1 has a certain volume. The MABR reactor body is 40 to 60 cm high and 20 to 30 cm in diameter. It needs to withstand a pressure of 1 MPa. The upper part of the reactor body 1 is connected to the upper cover flange 2, and the lower part of the reactor body 1 is connected to the ventilation flange 3. An inspection hole 10 is provided in the middle or upper middle part of the reactor body 1 and is connected to the inspection hole flange 11.

[0059] The inlet / outlet are both set at the upper end of the MABR reactor. The interface is connected to one end of the membrane assembly inside the reactor. The interface part is used for air intake and the rest is used for exhaust. Depending on the selection of the ventilation flange, some interfaces can also be in a closed state.

[0060] The water inlet 7 is used to meet the inlet of the fluid circulation flow / sequential flow and is set at 1 to 2 cm from the bottom; during normal operation, there is a certain amount of gas inside the MABR, which mainly comes from the denitrification process of microorganisms. Therefore, the water outlet 8 also has a certain gas transportation function. The water outlet 8 is connected to the gas-liquid separation device of the next level of the reactor and is set at 1 to 2 cm from the top.

[0061] The auxiliary water outlet 9 is used to meet the gas separation function of the MABR reactor. It is set on the opposite side of the water outlet and cooperates with the PLC system to control the switch of the auxiliary water outlet to complete the separation of the gas inside the reactor.

[0062] The inspection hole flange 11 is used for shutdown maintenance and to meet the needs of scientific experiments. It is set at 1 / 2 to 2 / 3 of the reactor, and the opening diameter depends on actual needs.

[0063] The upper cover flange 2 is mainly responsible for sealing the reactor and fixing the membrane components. The number and diameter of the flange openings depend on the number and size of the membrane components, such as Figure 4 The figure shows one of the forms: the number of openings is 6, the hole diameter is DN32, and the angle between adjacent holes is 60°; in addition, a pressure detection hole connection port 14 is provided in the middle position of the pore flange, the pressure detection hole connection port 14 is connected to the pressure detection hole 4, and the pressure detection hole 4 is connected to the pressure gauge for pressure detection.

[0064] Ventilation flange 3, the number and diameter of the ventilation flange openings match the vent holes of the upper cover flange, and are connected to the other end of the membrane assembly. According to the actual operation needs, the ventilation flange has two forms: Form 1 is: Figure 5 The ventilation component leaves a hole (i.e., opening 20). At this time, 1 / 2 of the membrane assembly is used for air intake and 1 / 2 of the membrane assembly is used for exhaust. Form 2 is: Figure 6 The ventilation component shown is fully enclosed (ie, the spacer 18). At this time, the membrane components on one side of the ventilation component can circulate gas, and the remaining membrane components do not participate in oxygen supply and are in an anaerobic / anoxic state.

[0065] The membrane assembly 6 is connected to the upper cover flange and the ventilation flange at both ends respectively. The membrane wire on the membrane assembly is made of ultra-microfiltration membrane wire made of PVDF, PP, PTFE, etc., which can withstand a wide range of pressure from 0 to 0.5 MPa. The inner / outer diameter of the membrane wire and the length of the membrane assembly depend on actual needs.

[0066] In this Example 2, the transient two-phase flow CFD simulation process of the MABR reactor and the simulation cloud map results under two states are also provided, including:

[0067] (1) Use Space Claim to extract and model the fluid domain and use Ansys Mesh to divide the mesh;

[0068] (2) Assuming microgravity (10 -5 Under g), a certain amount of gas is contained at fixed intervals inside the reactor. When the water inlet velocity is constant at 1 m / s, the outlet pressure is 0 Pa. An implicit numerical method is used in Ansys Fluent to discretize the solution process, and the VOF model tracks the gas-liquid interface.

[0069] (3) The gas-liquid two-phase cloud diagram before and after optimization is as follows Figure 8 、 Figure 9 After structural optimization, the gas phase inside the reactor can leave the reactor at a higher speed and participate in the next gas-liquid separation unit along the pipeline.

[0070] In this embodiment 2, a method for acclimating and cultivating a biofilm based on the optimized MABR reactor is also provided, comprising the following steps:

[0071] (1) Device assembly: The MABR reactor also needs to be equipped with an air source, a water pump and other monitoring equipment to form a MABR system. When the daily treatment capacity of aerospace wastewater is 5L / d, the operating parameters after experimental optimization are: aeration pressure of 0.15Mpa, circulation flow operation, circulation section flow rate of 2mm / s, hydraulic retention time HRT = 24h, operating water temperature of 20-30℃; ventilation flange is type 1, the number of membrane modules is 6, and the membrane fiber filling ratio is 225m 2 / m 3 .

[0072] (2) Seeding sludge: The initial influent COD is 100 mg / L and the ammonia nitrogen is 5 mg / L. The MABR startup work is carried out by continuously increasing the influent organic load. During the startup period, the MABR system can achieve a COD removal rate of more than 95%, and the removal of NH3-N is higher than 90%. Figure 10 、 Figure 11 As shown in the figure, there is no obvious accumulation of intermediate products during the biofilm formation and startup process. The biofilm formation and system startup of MABR are basically completed, and the system has the performance of simultaneous nitrification and denitrification.

[0073] (3) Start-up operation: The influent is adjusted to aerospace wastewater. After the effluent quality is stabilized, the operating parameters are fine-tuned to enable the MABR to achieve the best decarbonation and denitrification effects.

[0074] In summary, the MABR reactor provided in the present embodiment 2, from the perspective of improving the flow field, in the special microgravity environment of the space station, the flow form of the fluid is different from the surface gravity environment, which greatly affects the design and operation of the aerospace engineering system. CFD can overcome the shortcomings of short duration of ground experiments in microgravity environments, simplified pure numerical calculations and more assumptions, has strong predictive capabilities, and can quickly and intuitively correct and improve the MABR reactor structure. From the perspective of structural design, the bottom ventilation structure design can adjust the redox environment inside the reactor, adopt different ventilation forms for different influent water qualities, strengthen the biochemical effect of the reactor, and obtain higher simultaneous nitrification and denitrification efficiency (SND). The MABR reactor designed based on the present invention can be applied to aerospace environments and can be used to treat condensed water, domestic wastewater and crew urine or mixed wastewater generated by cooling and dehumidification in aerospace environments.

[0075] Example 3

[0076] like Figures 1 to 7As shown, in the present embodiment 3, there is provided a MABR reactor that can be applied to a microgravity environment and can process space wastewater, which includes a water outlet 8, a pressure detection port 4, an air inlet / outlet pipe (air vent 5), an upper cover flange 2, an auxiliary water outlet 9, a membrane assembly 6, an inspection hole flange 11, a MABR pool body (reactor body 1), a water inlet 7, a ventilation flange 3 and other fixed components. Among them, the reactor body 1 is the main pressure-bearing component, which is connected to the upper cover flange 2 and the lower part is connected to the ventilation flange 3. The middle or upper middle part is provided with an inspection hole and is connected to the inspection hole flange 11. The air inlet / outlet is arranged at the upper end of the MABR reactor, and the interface is connected to one end of the membrane assembly 6 inside the reactor body. Part of the interface is used for air intake, and the rest is used for exhaust or idle. According to the selection of the ventilation flange, the two ends of the membrane assembly can also be in a closed or idle state. At this time, the membrane assembly is in an anaerobic / anoxic state. The water inlet is located 1-2 cm from the bottom, the water outlet is located 1-2 cm from the top, and the auxiliary water outlet is located at the same position on the opposite side of the water outlet. The water outlet and auxiliary water outlet also serve a certain gas transportation function. The switch of the auxiliary water outlet is controlled by the solenoid valve. Both are connected to the gas-liquid separation device in the next stage of the reactor. The inspection port flange is located at 1 / 2 to 2 / 3 of the reactor body, and the opening diameter depends on actual needs. The upper cover flange mainly serves the function of sealing the reactor and fixing the membrane assembly. The number and diameter of the flange openings depend on actual needs. The middle position of the upper cover flange is the pressure detection hole connection port, which is connected to the pressure gauge. The ventilation flange is connected to the other end of the membrane assembly. According to actual operational needs, the ventilation flange can create an alternating aerobic, anoxic / aerobic state for the membrane assembly. The two ends of the membrane assembly are connected to the upper cover flange and the ventilation flange respectively. The membrane wire on the membrane assembly is made of ultra-microfiltration membrane wire made of PVDF, PP, PTFE, etc., which can withstand a wide range of pressures from 0 to 0.5 MPa. The inner / outer diameter of the membrane wire and the length of the membrane assembly depend on actual needs. The membrane wire filling ratio is 150 to 220 m 2 / m 3 .

[0077] In addition, two operating modes of the reactor are provided in this embodiment:

[0078] (1) Circulating flow: the water inflow is modeled after the sequential batch activated sludge process (SBR) model, with an HRT of 24 to 48 hours. The flow rate of the circulating flow is controlled by the cross-sectional velocity of the liquid surface inside the MABR reactor. The adjustment range of the cross-sectional velocity is generally 1 to 5 mm / s. The circulating flow model is suitable for wastewater with a water quality range of: COD ≥ 500 mg / L, ammonia nitrogen ≥ 50 mg / L, and TDS ≥ 3000 mg / L. This mode can be used if any one of the water quality ranges is met.

[0079] (2) Sequential flow: The sewage to be treated is continuously pumped into the MABR reactor. The pumping speed (or volumetric load VLR) is adjusted according to the water quality treatment. The sewage stays in the reactor for a certain period of time and then is discharged under pressure. Sequential flow is suitable for treating low-pollution-load wastewater. The quality of the water to be treated should be better than that of the circulating flow.

[0080] In addition, this embodiment provides two types of ventilation flanges to meet the different dissolved oxygen environments of the biofilm on the surface of the membrane assembly: (1) Type 1: Figure 5 As shown, at this time, all membrane filaments supply oxygen to the biofilm attached to the membrane filaments, and the oxidative environment of the biofilm gradually weakens as the thickness of the membrane filaments increases; (2) Form 2: Figure 6 As shown in the figure, at this time only part of the membrane fibers supply oxygen to the biofilm, and the other two ends of the membrane components are in a closed or idle state, and the whole is in an anaerobic / anoxic state. Artificial intervention in the redox environment inside the MABR reactor is conducive to improving the simultaneous nitrification and denitrification effect inside the reactor.

[0081] In addition, when the MABR reactor is operating normally, during the process of denitrification and carbon removal, the biofilm will continuously release mixed gases into the water environment. When the gas accumulates to a certain volume in a microgravity environment, it will seriously affect the effective volume of the MABR reactor. By setting a secondary outlet and combining the gas-liquid two-phase transient cloud diagram of single-side / double-side water outlet (such as Figure 8 、 9 ), in this embodiment, a method for improving the outward transport of gas from the inside of the reactor is also provided: (1) the secondary water outlet is controlled by the solenoid valve in a closed state. When the water inlet is stable, the gas from the lower to the middle will be discharged to the outside of the reactor along with the water flow, and the remaining residual gas will rise to the area around the secondary water outlet and be retained; (2) the secondary water outlet is adjusted to an open state, and the surrounding gas is discharged accordingly. The small amount of gas that is not discharged moves downward. This process is stable for about 30 to 60 seconds. (3) State 1 is restored, and the operation of (2) is repeated 5 to 6 times before normal operation is restored.

[0082] In summary, the reactor described in the embodiment of the present invention is applicable to a MABR reactor for treating aerospace wastewater in a microgravity environment. The biochemical treatment process with microbial treatment as the core is easily adapted to highly integrated environmental control and life protection, and has significant advantages such as low economic cost, strong resistance to environmental interference, and reusability. The use of ventilation flanges with different structures can create a variety of redox environments of different degrees inside the MABR reactor, and different operating modes can be set for different influent water qualities. Therefore, the MABR reactor has higher flexibility in sewage treatment. A method for exhausting gas produced inside the reactor is proposed. Combined with structural modification and a unique operating mode, the gas inside the reactor can be transported to the next gas-liquid separation unit to the greatest extent.

[0083] Although the above describes the specific embodiments of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solutions disclosed in the present invention without the need for creative work should be included in the scope of protection of the present invention.

Claims

1. A membrane aeration biofilm reactor capable of treating aerospace wastewater, characterized in that: include: Reactor body (1); The top of the reactor body (1) is provided with an upper cover flange (2), and the bottom of the reactor body (1) is provided with a ventilation flange (3); the upper cover flange (2) is provided with a pressure detection port (4) and a vent (5); a plurality of membrane assemblies (6) are provided in the internal space of the reactor body (1), and the membrane assemblies (6) are connected between the upper cover flange (2) and the ventilation flange (3); The bottom of the reactor body (1) is provided with a water inlet (7), and the upper part of the reactor body (1) is provided with a water outlet (8) and a secondary water outlet (9); The top of the reactor body (1) is provided with a top flange (12), and the upper cover flange (2) is connected to the top flange (12) by bolts; the bottom of the reactor body is provided with a bottom flange (13), and the ventilation flange (3) is connected to the bottom flange (13) by bolts; The membrane assembly includes connection ports at both ends and hollow fiber membranes located between the two connection ports; the membrane assembly has a membrane filling ratio of 150 to 225 m 2 / m 3 ; The ventilation flange includes a flange (16), an annular boss (17) is provided on the flange (16), and a partition bar (18) is provided inside the annular boss (17) to separate the inside of the annular boss (17); the flange (16) is provided with a connecting hole (19), and the connecting hole (19) is located inside the annular boss (17) and is evenly distributed on both sides of the partition bar (18).

2. The membrane aeration biofilm reactor capable of treating aerospace wastewater according to claim 1, characterized in that: The reactor body (1) is provided with an inspection hole (10), and the inspection hole (10) is connected to an inspection hole flange (11).

3. The membrane aeration biofilm reactor capable of treating aerospace wastewater according to claim 1 or 2, characterized in that: The number of the membrane modules is 6.

4. The membrane aeration biofilm reactor capable of treating aerospace wastewater according to claim 1, characterized in that: The spacer (18) is provided with an opening (20) for connecting the two parts in the annular boss (17).

5. The membrane aeration biofilm reactor capable of treating aerospace wastewater according to claim 4, characterized in that: A pressure detection port connection port (14) is provided in the middle of the upper cover flange (2), and a vent interface (15) is provided around the pressure detection port connection port (14).

6. The membrane aeration biofilm reactor capable of treating aerospace wastewater according to claim 5, characterized in that: One end of the membrane assembly (6) is connected to the vent interface (15), and the other end of the membrane assembly (6) is connected to the connection hole (19).

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