Wastewater treatment reconstruction system and reconstruction method based on MBR process
By retaining the anaerobic and anoxic zones in the MBR process and replacing the MBR membrane modules with a separation and sedimentation device in the aerobic zone, a two-zone sludge-water separation is formed, which solves the problems of short service life and high operation and maintenance costs of MBR membrane modules and achieves efficient and low-energy wastewater treatment.
Patent Information
- Application Number
- CN202610299370.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-03-11
- Publication Date
- 2026-06-05
Smart Images
Figure CN122144915A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of wastewater treatment technology, specifically relating to a wastewater treatment retrofit system and method based on MBR process. Background Technology
[0002] Membrane bioreactor (MBR) is a novel wastewater treatment process that combines efficient membrane separation technology with traditional biological treatment technology (activated sludge process). Its core lies in replacing the secondary sedimentation tank in the traditional activated sludge process with MBR membrane modules (usually ultrafiltration or microfiltration membranes) to separate sludge and water. However, the effluent flux of MBR membrane modules will decrease year by year, and the modules generally need to be completely replaced after 5 to 8 years of use. The use and maintenance costs are very high, and the energy consumption of the equipment such as purge blowers, permeate pumps, and backsuction pumps that are matched with MBR membrane modules is also very high. Summary of the Invention
[0003] This application provides a wastewater treatment retrofit system and method based on MBR technology, including but not limited to solving the problems of short service life, high operation and maintenance costs, and high energy consumption of membrane modules in MBR technology.
[0004] The technical solution adopted in the embodiments of this application is: Firstly, this application provides a wastewater treatment retrofit system based on MBR technology, the wastewater treatment retrofit system comprising: The reaction tank is physically divided into an anaerobic zone, an anoxic zone, a first aerobic zone, and a second aerobic zone, which are hydraulically connected sequentially. Separation and sedimentation device, both the first aerobic zone and the second aerobic zone are equipped with separation and sedimentation device, the separation and sedimentation device is used to separate mud and water to obtain clarified water.
[0005] In one embodiment, the wastewater treatment modification system further includes a first return channel, which connects the first aerobic zone and the second aerobic zone, and is used to return the mixed liquor from the second aerobic zone to the first aerobic zone.
[0006] In one embodiment, the wastewater treatment modification system further includes a second return channel, which connects the first aerobic zone and the anoxic zone, and is used to return the mixed liquor from the first aerobic zone to the anoxic zone.
[0007] In one embodiment, the wastewater treatment modification system further includes a third return channel, which connects the anoxic zone and the anaerobic zone, and is used to return the mixed liquor from the anoxic zone to the anaerobic zone.
[0008] In one embodiment, the wastewater treatment renovation system further includes a first aeration pipe located at the bottom of the first aerobic zone; and / or, the wastewater treatment renovation system further includes a second aeration pipe located at the bottom of the second aerobic zone.
[0009] In one embodiment, the wastewater treatment retrofit system further includes an advanced treatment facility located downstream of the separation and sedimentation unit. The advanced treatment facility is used to further treat the clarified water produced from the separation and sedimentation unit to improve the water quality of the clarified water.
[0010] In one embodiment, the separation and sedimentation device includes a frame assembly, a separation assembly, and an outlet weir. The frame assembly has a receiving space, and both the separation assembly and the outlet weir are disposed within the receiving space. The outlet weir is located at the top of the receiving space, and the separation assembly is located below the outlet weir. The separation assembly is used to separate mud and water to form clarified water above the separation assembly, and the outlet weir is used to collect the clarified water.
[0011] In one embodiment, the separation component includes a gas collecting pipe, a plurality of upper gas collecting hoods, and a plurality of lower gas collecting hoods arranged sequentially from top to bottom. The plurality of upper gas collecting hoods and the plurality of lower gas collecting hoods are arranged laterally at intervals, and the upper gas collecting hoods and the lower gas collecting hoods are arranged in a one-to-one correspondence. The gas collecting pipe, the upper gas collecting hoods, and the lower gas collecting hoods are connected sequentially.
[0012] In one embodiment, the lower gas collection hood includes a first inclined plate and a second inclined plate, both of which are inclined so that the distance between the first inclined plate and the second inclined plate gradually decreases from bottom to top. The upper gas collection hood includes a third inclined plate and a fourth inclined plate, both of which are inclined so that the distance between the third inclined plate and the fourth inclined plate gradually decreases from bottom to top.
[0013] Secondly, this application also provides a modification method based on MBR technology. The MBR process system includes an anaerobic zone, an anoxic zone, an aerobic zone, and an MBR membrane tank connected in sequence. The modification method includes: The anaerobic zone and the anoxic zone are retained; A separation and sedimentation device is installed in the aerobic zone so that the aerobic zone becomes the first aerobic zone capable of separating mud and water. The MBR membrane modules in the MBR membrane tank are replaced with a separation and sedimentation device, so that the MBR membrane tank becomes a second aerobic zone capable of separating sludge and water.
[0014] Compared with the prior art, the beneficial effects of this application are as follows: The wastewater treatment retrofit system provided in this application is based on the MBR process system. Specifically, based on the original MBR tank, the original anaerobic and anoxic zones are retained, and a separation and sedimentation device is installed in the original aerobic zone to make it the first aerobic zone. The original MBR membrane modules in the original MBR membrane tank are replaced with the separation and sedimentation device to make the MBR membrane tank the second aerobic zone. Thus, the wastewater treatment retrofit system of this application is obtained. Both the first and second aerobic zones are aerobic sedimentation coupling zones. This aerobic sedimentation coupling zone can not only realize the aerobic reaction between activated sludge and wastewater, but also realize sludge-water separation using the separation and sedimentation device. Compared with the MBR process, since the separation and sedimentation device replaces the original MBR membrane modules, it overcomes the technical problems of short service life, high operation and maintenance costs, and high energy consumption of MBR membrane modules. In addition, this application is equipped with separation and sedimentation devices in both the first and second aerobic zones, so that the clarified water can be discharged from either the separation and sedimentation device in the first or the second aerobic zone, thereby distributing the total effluent volume between the first and second aerobic zones. This avoids the problem of excessive surface load in the two reaction zones and allows both reaction zones to achieve better mud-water separation. Attached Figure Description
[0015] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0016] Figure 1 A perspective view of the wastewater treatment retrofit system provided in the embodiments of this application.
[0017] Figure 2 A simplified schematic diagram of the wastewater treatment retrofit system provided in the embodiments of this application.
[0018] Figure 3 A simplified schematic diagram illustrating the working principle of the separation and precipitation device provided in the embodiments of this application.
[0019] Figure 4 This is a schematic diagram of the separation component in the separation and precipitation apparatus provided in the embodiments of this application.
[0020] Explanation of key figure labels: Reactor 10, anaerobic zone A1, anoxic zone A2, first aerobic zone A3, pre-aerobic zone A31, post-aerobic zone A32, second aerobic zone A4, separation and sedimentation device 20, frame assembly 21, separation assembly 22, gas collecting pipe 221, upper gas collecting hood 222, third inclined plate 2221, fourth inclined plate 2222, lower gas collecting hood 223, first inclined plate 2231, second inclined plate 2232, effluent weir 23, first return channel 30, second return channel 40, third return channel 50, first aeration pipe 60, second aeration pipe 70, inlet pipe 80, first flow channel Y1, second flow channel Y2, third flow channel Y3, containment space X1, first liquid inlet X2, air outlet X3, first inlet X4, first outlet X5, second inlet X6, second outlet X7. Detailed Implementation
[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0022] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.
[0023] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.
[0024] Furthermore, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.
[0025] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, components, or parts (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, components, or parts. Unless otherwise stated, "a plurality of" means two or more.
[0026] The technical solution of this application will be further described below with reference to the embodiments and accompanying drawings.
[0027] Please refer to Figure 1 and Figure 2 This application provides a wastewater treatment retrofit system based on MBR technology, the wastewater treatment retrofit system including: a reaction tank 10 and a separation and sedimentation device 20.
[0028] The reaction tank 10 is physically divided into an anaerobic zone A1, an anoxic zone A2, a first aerobic zone A3, and a second aerobic zone A4, and the anaerobic zone A1, the anoxic zone A2, the first aerobic zone A3, and the second aerobic zone A4 are hydraulically connected in sequence.
[0029] Separation and sedimentation device 20 is provided in both the first aerobic zone A3 and the second aerobic zone A4. The separation and sedimentation device 20 is used to separate mud and water to obtain clarified water.
[0030] Among them, the anoxic zone A2 is used for denitrification, that is, under anoxic conditions, denitrifying bacteria in activated sludge use organic matter in wastewater to reduce nitrate nitrogen into harmless nitrogen gas, which then escapes from the water into the atmosphere, thereby achieving denitrification.
[0031] Among them, the anaerobic zone A1 is used to release phosphorus and store phosphorus uptake energy. That is, under anaerobic conditions, polyphosphate-accumulating bacteria in activated sludge release phosphorus into the wastewater, while absorbing and storing easily degradable organic matter in the wastewater, in preparation for subsequent excessive phosphorus uptake in the aerobic zone.
[0032] The first aerobic zone A3 and the second aerobic zone A4 are used to oxidize organic matter, nitrify ammonia nitrogen, and absorb excess phosphorus. Under aeration and oxygenation conditions, the aerobic bacteria in the activated sludge completely oxidize and decompose the remaining organic matter in the wastewater; the nitrifying bacteria in the activated sludge convert ammonia nitrogen in the wastewater into nitrate nitrogen; at the same time, the polyphosphate-accumulating bacteria in the activated sludge use the energy stored in the anaerobic zone A1 to absorb excess phosphorus from the wastewater into their bodies, thereby achieving efficient removal of pollutants.
[0033] In practical applications, the mixture of wastewater and activated sludge flows from the anaerobic zone A1 to the anoxic zone A2, then from the anoxic zone A2 to the first aerobic zone A3, and finally from the first aerobic zone A3 to the second aerobic zone A4. During this process, some of the mixture enters the separation and sedimentation device 20, where the activated sludge settles in the lower part, resulting in clarified water (sludge-water separation) at the top of the separation and sedimentation device 20. This clarified water is then collected and discharged from the system. Therefore, the first aerobic zone A3 and the second aerobic zone A4, equipped with the separation and sedimentation device 20, not only enable aerobic reactions between activated sludge and wastewater but also achieve sludge-water separation using the separation and sedimentation device 20. This makes the first aerobic zone A3 and the second aerobic zone A4 essentially aerobic sedimentation coupling zone.
[0034] Furthermore, if the separation and sedimentation device 20 is only located in the first aerobic zone A3 and not in the second aerobic zone A4, the surface load of the first aerobic zone A3 will be too high, resulting in incomplete sludge settling and poor sludge-water separation. Similarly, if the separation and sedimentation device 20 is only located in the second aerobic zone A4 and not in the first aerobic zone A3, the surface load of the second aerobic zone A4 will be too high, resulting in incomplete sludge settling and poor sludge-water separation. This application provides separation and sedimentation devices 20 in both the first aerobic zone A3 and the second aerobic zone A4, so that clarified water can be discharged from both the separation and sedimentation devices 20 in the first aerobic zone A3 and the second aerobic zone A4, thereby distributing the total effluent volume between the two aerobic zones A3 and A4. This avoids the problem of excessive surface load in these two reaction zones, allowing both reaction zones to achieve better sludge-water separation.
[0035] The wastewater treatment retrofit system provided in this application is based on the MBR process system. Specifically, based on the original MBR tank, the original anaerobic zone A1 and anoxic zone A2 are retained, and a separation and sedimentation device 20 is installed in the original aerobic zone to make this aerobic zone the first aerobic zone A3. The original MBR membrane modules in the original MBR membrane tank are replaced with the separation and sedimentation device 20 to make the MBR membrane tank the second aerobic zone A4. Thus, the wastewater treatment retrofit system of this application is obtained. The first aerobic zone A3 and the second aerobic zone A4 are both aerobic sedimentation coupling zones. This aerobic sedimentation coupling zone can not only realize the aerobic reaction between activated sludge and wastewater, but also realize sludge-water separation using the separation and sedimentation device 20. Compared with the MBR process, since the separation and sedimentation device 20 replaces the original MBR membrane modules, the technical problems of short service life, high operation and maintenance costs, and high energy consumption of MBR membrane modules are overcome. In addition, this application provides separation and sedimentation devices 20 in both the first aerobic zone A3 and the second aerobic zone A4, so that the clarified water can be discharged from the separation and sedimentation device 20 in the first aerobic zone A3 or the separation and sedimentation device 20 in the second aerobic zone A4, thereby distributing the total effluent volume between the first aerobic zone A3 and the second aerobic zone A4. This avoids the problem of excessive surface load in these two reaction zones and allows both reaction zones to achieve better mud-water separation effect.
[0036] Please refer to Figure 2 In one embodiment, the wastewater treatment modification system further includes an inlet pipe 80 for inputting wastewater into the anaerobic zone A1. The outlet end of the inlet pipe 80 may be located above the anaerobic zone A1.
[0037] Please refer to Figure 2 In one embodiment, the wastewater treatment modification system further includes a first return channel 30, which connects the first aerobic zone A3 and the second aerobic zone A4. The first return channel 30 is used to return the mixed liquor from the second aerobic zone A4 to the first aerobic zone A3.
[0038] Both the first aerobic zone A3 and the second aerobic zone A4 are aerobic zones. The return flow of the mixed liquid from the second aerobic zone A4 to the first aerobic zone A3 retains the original MBR process reflux route, which reduces modifications and lowers costs.
[0039] Optionally, the first aerobic zone A3 receives the mixed liquor (containing ammonia nitrogen and residual organic matter) from the upstream anoxic zone A2, and simultaneously receives the mixed liquor (rich in nitrates) returned from the second aerobic zone A4. Dissolved oxygen in the first aerobic zone A3 can be controlled to be relatively high. Under these conditions, the exterior of the activated sludge flocs is an aerobic environment, where nitrifying bacteria oxidize the ammonia nitrogen in the influent into nitrite and nitrate. Simultaneously, due to oxygen mass transfer resistance, an anoxic or even anaerobic microenvironment naturally forms inside the flocs. Nitrates returned from the second aerobic zone A4 can diffuse into these anoxic microenvironments, while organic matter (carbon source) from the upstream anoxic zone A2 that has not been fully consumed is utilized by denitrifying bacteria, reducing nitrates to nitrogen gas, which is then discharged. Thus, nitrification (outside the flocs) and denitrification (inside the flocs) occur simultaneously in the first tank, i.e., simultaneous nitrification and denitrification. The dissolved oxygen in the second aerobic zone A4 can be controlled at a relatively high level, ensuring a thoroughly aerobic environment. The second aerobic zone A4 completely oxidizes the remaining ammonia nitrogen that was not fully oxidized in the first aerobic zone A3 into nitrate, ensuring that the ammonia nitrogen in the effluent absolutely meets the standards. The nitrate-rich mixed liquor produced in the second aerobic zone A4 is used as raw material for recirculation back to the first aerobic zone A3 for denitrification.
[0040] Please refer to Figure 2 In one embodiment, the wastewater treatment modification system further includes a second return channel 40, which connects the first aerobic zone A3 and the anoxic zone A2. The second return channel 40 is used to return the mixed liquor from the first aerobic zone A3 to the anoxic zone A2. Returning the mixed liquor from the first aerobic zone A3 to the anoxic zone A2 provides nitrates for the denitrification reaction, thereby completing biological denitrification. That is, the nitrogen form completes the full transformation pathway from ammonia nitrogen in wastewater → nitrates in the first aerobic zone A3 → nitrogen gas in the anoxic zone A2.
[0041] Please refer to Figure 2 In one embodiment, the wastewater treatment modification system further includes a third return channel 50, which connects the anoxic zone A2 and the anaerobic zone A1. The third return channel 50 is used to return the mixed liquor from the anoxic zone A2 to the anaerobic zone A1. The anoxic zone A2 is located after the anaerobic zone A1. The nitrate-rich mixed liquor from the aerobic zone first enters the anoxic zone A2, where the nitrates are almost completely consumed by denitrification. Then, the denitrified mixed liquor (mainly activated sludge) from the anoxic zone A2, with extremely low nitrate concentration, is returned to the front end of the anaerobic zone A1. This ensures a "pure" anaerobic environment for polyphosphate-accumulating bacteria, avoiding interference from nitrates.
[0042] Please refer to Figure 3In one embodiment, the wastewater treatment modification system further includes a first aeration pipe 60, which is located at the bottom of the first aerobic zone A3. The first aeration pipe 60 is also located in both the front aerobic zone and the rear aerobic zone.
[0043] Please refer to Figure 3 In one embodiment, the wastewater treatment modification system further includes a second aeration pipe 70, which is located at the bottom of the second aerobic zone A4.
[0044] Both the first aeration pipe 60 and the second aeration pipe 70 may include a main pipe and multiple branch pipes. The branch pipes are arranged at intervals along the length of the main pipe and connected to it. The main pipe is used to connect to an air supply source (such as a blower). When the air supply source is working, external gas (such as air or pure oxygen) is first introduced into the main pipe and then released from the branch pipes into the aerobic zone to provide oxygen to the aerobic microorganisms. When the first aeration pipe 60 and the second aeration pipe 70 aerate, a large number of bubbles are generated. These bubbles disturb the water flow as they rise, allowing the wastewater, activated sludge, and oxygen to mix thoroughly, thereby ensuring that the activated sludge and wastewater have sufficient contact and reaction.
[0045] In one embodiment, the wastewater treatment retrofit system further includes an advanced treatment facility located downstream of the separation and sedimentation device 20. The advanced treatment facility is used to further treat the clarified water produced from the separation and sedimentation device 20 to improve the water quality of the clarified water.
[0046] Although the clarified water discharged from the separation and sedimentation unit 20 has become clear, it still contains dissolved pollutants and fine suspended solids. Therefore, an advanced treatment facility is installed downstream of the separation and sedimentation unit 20, and the clarified water discharged from the separation and sedimentation unit 20 will flow to the advanced treatment facility for further treatment. This advanced treatment facility can be, but is not limited to, a filter cloth filter. For example, mechanical filtration using the tiny pores of a filter cloth woven from fibers can intercept residual fine suspended particles, colloidal substances, and bioflocs in the water, thereby significantly reducing the suspended solids concentration and turbidity of the effluent.
[0047] Please refer to Figure 2 In one embodiment, the first aerobic zone A3 is divided into a front aerobic zone A31 and a rear aerobic zone A32 along the length of the wastewater treatment modification system. The front aerobic zone A31 is hydraulically connected to the anoxic zone A2, and the rear aerobic zone A32 is hydraulically connected to the second aerobic zone A4. The separation and sedimentation device 20 is located in the rear aerobic zone A32.
[0048] In this design, the pre-aerobic zone A31 and the post-aerobic zone A32 are not physically separated; they are simply different areas within the first aerobic zone A3. In one embodiment, the volumes of the pre-aerobic zone A31 and the post-aerobic zone A32 are exactly the same; in another embodiment, the volume of the pre-aerobic zone A31 is larger than the volume of the post-aerobic zone A32; and in yet another embodiment, the volume of the pre-aerobic zone A31 is smaller than the volume of the post-aerobic zone A32. Placing the separation and sedimentation device 20 in the post-aerobic zone A32 ensures that the wastewater and activated sludge first undergo sufficient contact and reaction in the pre-aerobic zone A31 before entering the separation and sedimentation device 20 to obtain clarified water, thus guaranteeing better water quality.
[0049] Please refer to Figure 3 In one embodiment, the separation and sedimentation device 20 includes a frame assembly 21, a separation assembly 22, and an outlet weir 23. The frame assembly 21 has a receiving space X1. The separation assembly 22 and the outlet weir 23 are both disposed within the receiving space X1, with the outlet weir 23 located at the top of the receiving space X1 and the separation assembly 22 located below the outlet weir 23. The separation assembly 22 is used to achieve mud-water separation to form clarified water above the separation assembly 22, and the outlet weir 23 is used to collect the clarified water.
[0050] The frame assembly 21 can be composed of multiple partitions, the material of which can be, but is not limited to, stainless steel, fiberglass, polyethylene, etc. Multiple partitions are connected end-to-end to enclose the containing space X1. The projection shape of the containing space X1 on the ground can be, but is not limited to, circular, angular, elliptical, etc. The containing space X1 is divided into a first region and a second region from bottom to top. The separation assembly 22 is located in the first region, and the effluent weir 23 is located at the top of the second region. Taking the first aerobic zone A3 as an example (the second aerobic zone A4 is similar): the first region is connected to the first aerobic zone A3, meaning the mixed liquor in the first aerobic zone A3 can enter the first region. When the mixed liquor enters the first region from the first aerobic zone A3, the separation assembly 22 functions, causing the activated sludge to settle downwards, achieving sludge-water separation, thus resulting in clarified water in the second region. This clarified water is collected by the effluent weir 23 and then discharged from the system.
[0051] The top of the frame assembly 21 can be flush with or extend beyond the top of the reaction tank 10. This arrangement is to prevent mixed liquid outside the separation and sedimentation device 20 from flowing into the clarified water from the top of the frame assembly 21.
[0052] Please refer to Figure 3In one embodiment, the separation component 22 includes a gas collecting pipe 221, a plurality of upper gas collecting hoods 222, and a plurality of lower gas collecting hoods 223 arranged sequentially from top to bottom. The plurality of upper gas collecting hoods 222 and the plurality of lower gas collecting hoods 223 are arranged laterally at intervals, and the upper gas collecting hoods 222 and the lower gas collecting hoods 223 are arranged in a one-to-one correspondence. The gas collecting pipe 221, the upper gas collecting hoods 222, and the lower gas collecting hoods 223 are connected sequentially.
[0053] A first flow channel Y1 is formed by a gap between adjacent upper gas collecting hoods 222 and lower gas collecting hoods 223. A second flow channel Y2 is formed by a gap between two adjacent lower gas collecting hoods 223. A third flow channel Y3 is formed by a gap between two adjacent upper gas collecting hoods 222.
[0054] In practical applications (taking the first aerobic zone A3 as an example, and the same applies to the second aerobic zone A4), the bubbles generated by the aeration pipe at the bottom of the first aerobic zone A3 will gradually rise. Due to the surface tension and viscosity of water, the bubbles will carry the mixed liquid upwards as they rise. The bubbles below the separation and sedimentation device 20 will first carry the mixed liquid into the lower gas collection hood 223, and then into the upper gas collection hood 222. The bubbles and the mixed liquid entering the upper gas collection hood 222 are separated into two paths. The bubbles continue to rise until they reach the gas collection pipe 221, where the gas in the bubbles is collected, while the mixed liquid flows out from the first flow channel Y1. The mixed liquid flowing out from the first channel Y1 will be divided into two paths again. As the bubbles rise, they carry part of the mixed liquid away from the first aerobic zone A3 and move upward. Therefore, part of the mixed liquid will flow from the first channel Y1 to the second channel Y2 and move downward to the first aerobic zone A3 (the first flow path) to supplement the first aerobic zone A3 below the separation and sedimentation device 20. At the same time, as the effluent weir 23 continuously discharges clarified water from the system at the top of the separation and sedimentation device 20, part of the mixed liquid will flow from the first channel Y1 to the third channel Y3 and move upward to the effluent weir 23 (the second flow path). In the process of the mixed liquor flowing through the second flow path, the activated sludge will settle under the influence of weight as it moves upward, forming clarified water above the separation component 22. The settled activated sludge will fall and accumulate between the two adjacent lower gas collection hoods 223 or on top of the lower gas collection hoods 223. Therefore, the mixed liquor flowing through the first flow path will carry away this settled and accumulated activated sludge, allowing this portion of activated sludge to return to the first aerobic zone A3 below the separation and sedimentation device 20. Furthermore, after this portion of activated sludge settles and accumulates, its concentration ratio will decrease, making the activated sludge easier to settle, i.e., easier to achieve sludge-water separation. It can be understood that after the mixed liquor flowing through the first flow path returns to the first aerobic zone A3, it will re-enter the separation and sedimentation device 20 with the air bubbles, thus forming a hydraulic cycle inside and outside the lower gas collection hood 223.
[0055] Please refer to Figure 3 In one embodiment, the first aerobic zone A3 is provided with a first liquid inlet X2, and the first aerobic zone A3 is connected to the second aerobic zone A4 through the first liquid inlet X2. The gas collecting pipe 221 of the separation and sedimentation device 20 in the first aerobic zone A3 extends out of the frame assembly 21, and the gas outlet X3 of the gas collecting pipe 221 is located below the first aerobic zone A3.
[0056] In practical applications, the gas collected by the gas collecting pipe 221 is discharged from the gas outlet X3. After being discharged, the gas forms bubbles that rise. Due to the surface tension and viscosity of water, the bubbles carry the mixed liquid upwards. Simultaneously, since the gas outlet X3 of the gas collecting pipe 221 is located below the first liquid inlet X2, the rising bubbles can promote the flow of the mixed liquid from the first aerobic zone A3 into the second aerobic zone A4. Thus, no additional power source is needed to drive the mixed liquid from the first aerobic zone A3 to the second aerobic zone A4, or the driving force of the power source can be reduced, thereby achieving energy savings. The number of gas outlets X3 can be one or more, for example, 1, 2, 3, 4, 5, or 6.
[0057] Please refer to Figure 4 In one embodiment, the lower gas collecting hood 223 has a first inlet X4 and a first outlet X5, and the upper gas collecting hood 222 has a second inlet X6 and a second outlet X7. The first inlet X4, the first outlet X5, the second inlet X6, and the second outlet X7 are sequentially connected from bottom to top, and the second outlet X7 is connected to the gas collecting pipe 221. During the rising process, the bubbles will sequentially enter the gas collecting pipe 221 through the first inlet X4, the first outlet X5, the second inlet X6, and the second outlet X7 to be collected. The size of the first inlet X4 is larger than the size of the first outlet X5, and the size of the second inlet X6 is larger than the size of the second outlet X7. That is, both the lower gas collecting hood 223 and the upper gas collecting hood 222 have a structure that gradually narrows from bottom to top, which facilitates the gradual collection of gas into the gas collecting pipe 221. It should be noted that the lower gas collecting hood 223 and the upper gas collecting hood 222 only need to meet the above-mentioned narrowing requirements; their specific shapes can be trapezoidal, conical, etc., and are not limited here.
[0058] Please refer to Figure 4In one embodiment, the lower gas collection hood 223 includes a first inclined plate 2231 and a second inclined plate 2232. Both the first inclined plate 2231 and the second inclined plate 2232 are inclined so that the distance between them gradually decreases from bottom to top, forming a first inlet X4 and a first outlet X5. It is understood that the inclined arrangement of the first inclined plate 2231 and the second inclined plate 2232 facilitates the sliding of activated sludge settling on the top of the first inclined plate 2231 and the second inclined plate 2232 between adjacent lower gas collection hoods 223, thereby making it easier for the mixed liquid flowing through the first flow path to carry away this settled activated sludge.
[0059] The upper gas collection hood 222 includes a third inclined plate 2221 and a fourth inclined plate 2222. Both the third inclined plate 2221 and the fourth inclined plate 2222 are inclined so that the distance between them gradually decreases from bottom to top, forming a second inlet X6 and a second outlet X7. It is understood that the inclined arrangement of the third inclined plate 2221 and the fourth inclined plate 2222 facilitates the sliding of activated sludge settled on the top of the third inclined plate 2221 and the fourth inclined plate 2222 onto the top of the lower gas collection hood 223, and then from the top of the lower gas collection hood 223 down to between two adjacent lower gas collection hoods 223. This allows the mixed liquid flowing through the first flow path to carry away this settled and accumulated activated sludge.
[0060] This application also provides a modification method based on MBR technology. The MBR process system includes an anaerobic zone, an anoxic zone, an aerobic zone and an MBR membrane tank connected in sequence. The modification method includes steps S100, S200 and S300. The description of steps S100, S200 and S300 is as follows.
[0061] S100: Retain the anaerobic zone A1 and the anoxic zone A2.
[0062] S200: A separation and sedimentation device 20 is installed in the aerobic zone so that the aerobic zone becomes the first aerobic zone A3 capable of separating mud and water.
[0063] S300: Replace the MBR membrane module in the MBR membrane tank with a separation sedimentation device 20 so that the MBR membrane tank becomes a second aerobic zone A4 capable of achieving sludge-water separation.
[0064] For the modified anaerobic zone A1, anoxic zone A2, first aerobic zone A3, second aerobic zone A4, separation and sedimentation device 20, etc., please refer to the description and corresponding drawings in the previous structural embodiments, and will not be repeated here. It should be noted that there is no limitation on the order of the above steps S100, S200, and S300; each step can be performed simultaneously or sequentially. For example, the order of the modification method can be S100, S200, S300, or it can be S300, S200, S100, etc.
[0065] The technical means disclosed in this application are not limited to those disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principles of this application, and these improvements and modifications are also considered to be within the scope of protection of this application.
Claims
1. A wastewater treatment retrofit system based on MBR technology, characterized in that, The wastewater treatment retrofit system includes: The reaction tank (10) is physically divided into an anaerobic zone (A1), an anoxic zone (A2), a first aerobic zone (A3), and a second aerobic zone (A4), wherein the anaerobic zone (A1), the anoxic zone (A2), the first aerobic zone (A3), and the second aerobic zone (A4) are hydraulically connected in sequence; and Separation and sedimentation device (20) is provided in both the first aerobic zone (A3) and the second aerobic zone (A4). The separation and sedimentation device (20) is used to separate mud and water to obtain clarified water.
2. The wastewater treatment retrofit system as described in claim 1, characterized in that, The wastewater treatment renovation system also includes a first return channel (30), which connects the first aerobic zone (A3) and the second aerobic zone (A4). The first return channel (30) is used to return the mixed liquor of the second aerobic zone (A4) to the first aerobic zone (A3).
3. The wastewater treatment retrofit system as described in claim 1, characterized in that, The wastewater treatment renovation system also includes a second return channel (40), which connects the first aerobic zone (A3) and the anoxic zone (A2). The second return channel (40) is used to return the mixed liquor of the first aerobic zone (A3) to the anoxic zone (A2).
4. The wastewater treatment retrofit system as described in claim 1, characterized in that, The wastewater treatment renovation system also includes a third return channel (50), which connects the anoxic zone (A2) and the anaerobic zone (A1). The third return channel (50) is used to return the mixed liquor from the anoxic zone (A2) to the anaerobic zone (A1).
5. The wastewater treatment retrofit system as described in claim 1, characterized in that, The wastewater treatment renovation system further includes a first aeration pipe (60), which is located at the bottom of the first aerobic zone (A3); and / or, the wastewater treatment renovation system further includes a second aeration pipe (70), which is located at the bottom of the second aerobic zone (A4).
6. The wastewater treatment retrofit system as described in claim 1, characterized in that, The wastewater treatment renovation system also includes an advanced treatment facility, which is located downstream of the separation and sedimentation device (20). The advanced treatment facility is used to further treat the clarified water produced from the separation and sedimentation device (20) to improve the water quality of the clarified water.
7. The wastewater treatment renovation system as described in any one of claims 1 to 6, characterized in that, The separation and sedimentation device (20) includes a frame assembly (21), a separation assembly (22), and an outlet weir (23). The frame assembly (21) has a receiving space (X1). The separation assembly (22) and the outlet weir (23) are both located in the receiving space (X1), and the outlet weir (23) is located at the top of the receiving space (X1). The separation assembly (22) is located below the outlet weir (23). The separation assembly (22) is used to achieve mud-water separation to form clear water above the separation assembly (22). The outlet weir (23) is used to collect the clear water.
8. The wastewater treatment retrofit system as described in claim 7, characterized in that, The separation component (22) includes a gas collecting pipe (221), multiple upper gas collecting hoods (222), and multiple lower gas collecting hoods (223) arranged sequentially from top to bottom. The multiple upper gas collecting hoods (222) and multiple lower gas collecting hoods (223) are arranged horizontally at intervals, and the upper gas collecting hoods (222) and the lower gas collecting hoods (223) are arranged in a one-to-one correspondence. The gas collecting pipe (221), the upper gas collecting hoods (222), and the lower gas collecting hoods (223) are connected sequentially.
9. The wastewater treatment retrofit system as described in claim 8, characterized in that, The lower gas collection hood (223) includes a first inclined plate (2231) and a second inclined plate (2232). The first inclined plate (2231) and the second inclined plate (2232) are both inclined so that the distance between the first inclined plate (2231) and the second inclined plate (2232) gradually decreases from bottom to top. The upper gas collection hood (222) includes a third inclined plate (2221) and a fourth inclined plate (2222). The third inclined plate (2221) and the fourth inclined plate (2222) are both inclined so that the distance between the third inclined plate (2221) and the fourth inclined plate (2222) gradually decreases from bottom to top.
10. A modification method based on MBR technology, characterized in that, The MBR process system includes an anaerobic zone, an anoxic zone, an aerobic zone, and an MBR membrane tank connected in sequence. The modification method includes: The anaerobic zone (A1) and the anoxic zone (A2) are retained. A separation and sedimentation device (20) is installed in the aerobic zone so that the aerobic zone becomes the first aerobic zone (A3) capable of achieving mud-water separation. The MBR membrane module in the MBR membrane tank is replaced with a separation sedimentation device (20) so that the MBR membrane tank becomes a second aerobic zone (A4) capable of achieving sludge-water separation.