Modularized anoxic-aerobic biological membrane sewage treatment system

Abstract

The embodiment of the utility model discloses a modularized anoxic and aerobic biological membrane sewage treatment system, and relates to the technical field of sewage treatment. The sewage treatment system comprises a biochemical pool body, a first anoxic biological membrane module, an aerobic biological membrane module and a nitrification liquid backflow system, the biochemical pool body comprises a water inlet region, an anoxic region and an aerobic region which are connected in sequence according to the water flow direction; the first anoxic biological membrane module is arranged in the anoxic zone, and the aerobic biological membrane module is arranged in the aerobic zone; the nitrification liquid backflow system is arranged at the water outlet end of the aerobic zone and is used for enabling the nitrification liquid to flow back to the anoxic zone. The sewage treatment system is a pure biofilm process water treatment process system, combines a biofilm process, an AO process and a plant absorption enhancement technology, can efficiently remove pollutants, has relatively strong impact resistance to inflow water quality, and can stably operate under the environmental condition of relatively large inflow water load fluctuation.

Description

Technical Field

[0001] The utility model relates to the technical field of sewage treatment, in particular to a modular anoxic aerobic biofilm sewage treatment system. Background Art

[0002] With the rapid economic development and the acceleration of urban-rural integration, people have higher and higher requirements for the quality of living environment. The environmental pollution problems caused by low-pollution water bodies such as sewage treatment plant tailwater, urban surface runoff and rural domestic sewage have attracted widespread attention. The treatment of low-pollution water bodies has become the focus of sewage treatment.

[0003] Low-polluted water bodies generally have the characteristics of wide pollution range, large fluctuations in water quality and quantity, low carbon-nitrogen ratio and poor biodegradability. The water quality of low-polluted water bodies such as rural sewage is different from that of urban sewage. If the urban sewage treatment process (activated sludge method) is copied to purify such water bodies, not only will the professional requirements for equipment and operation and maintenance management be high, but the activated sludge process is prone to sludge loss when the inlet conditions are unstable, resulting in insufficient microbial biomass and poor effluent water quality. The biofilm process is considered to be an effective means of treating low-polluted water bodies due to its strong microbial retention ability, few environmental factors, and low sludge production. However, most of the existing biofilm processes are aerobic, and have the ability to quickly and efficiently remove pollutants such as COD and ammonia nitrogen, but the system lacks an anaerobic environment suitable for denitrification reactions and has a weak ability to remove total nitrogen. Utility Model Content

[0004] The technical problem to be solved by the utility model is that the prior art has a weak ability to remove total nitrogen in sewage, resulting in the problem that the quality of the treated water does not meet the requirements.

[0005] In order to solve the above problems, the utility model provides a modular anoxic aerobic biofilm sewage treatment system, which is suitable for the treatment of low-pollution water bodies such as rural sewage. The system can improve the total nitrogen removal effect of sewage by combining AO process and modular fixed biofilm technology. At the same time, it has the advantages of simple construction, compact structure, economical and convenient operation and maintenance, and stable effect.

[0006] Specifically, the technical solution provided by the utility model is as follows:

[0007] A modular anoxic aerobic biofilm sewage treatment system comprises a biochemical tank body, a first anoxic biofilm module, an aerobic biofilm module and a nitrification liquid reflux system; according to the water flow direction, the biochemical tank body comprises a water inlet area, anoxic area and aerobic area connected in sequence; the first anoxic biofilm module is arranged in the anoxic area, and the aerobic biofilm module is arranged in the aerobic area; the nitrification liquid reflux system is arranged at the water outlet of the aerobic area, and the nitrification liquid reflux system is used to return the nitrification liquid to the anoxic area.

[0008] The modular anoxic aerobic biofilm wastewater treatment system provided in this scheme is a pure biofilm process. The return nitrification liquid does not contain activated sludge. Only the nitrification liquid needs to be returned, and there is no need for sludge return. Therefore, this system has no sludge return system.

[0009] In some embodiments, the water inlet area, anoxic area and aerobic area can be independent pool bodies connected by pipes; a pool can be divided into multiple different areas by multiple partitions; or multiple pools can be divided into multiple different areas by one or more partitions, and then the multiple pools are connected by pipes. The partition material is consistent with the pool body material, and the pools are divided by casting, walling, welding, etc.

[0010] For example, two partitions are used to separate the biochemical pond body into a water inlet zone, an anoxic zone and an aerobic zone.

[0011] In some embodiments, the water inlet area, anoxic area and aerobic area can be newly built or renovated sewage treatment pools, or integrated equipment pools, which can be flexibly designed according to needs. The biochemical pool body can be a concrete structure pool body, a brick pool body, a carbon steel tank pool body, a stainless steel tank pool body, etc.

[0012] It should be noted that in order to reduce the dissolved oxygen in the reflux nitrification liquid and reduce the impact of the dissolved oxygen carried by the reflux nitrification liquid on the anoxic environment of the anoxic zone, the aerobic zone can be designed with a gradually weakened aeration intensity. At this time, the nitrification liquid reflux system is installed at the end of the aerobic zone outlet.

[0013] A further technical solution is that the biochemical pool body also includes an oxygen removal zone; the oxygen removal zone is connected to the aerobic zone, and the nitrification liquid reflux system is arranged in the oxygen removal zone; the oxygen removal zone is used to perform oxygen removal treatment on the nitrification liquid, and the nitrification liquid reflux system is used to return the nitrification liquid after the oxygen removal treatment to the anoxic zone.

[0014] In order to reduce the dissolved oxygen in the refluxed nitrification liquid and reduce the impact of the dissolved oxygen carried by the refluxed nitrification liquid on the anoxic environment of the anoxic zone, this scheme adds an oxygen removal zone at the end of the aerobic zone outlet. After the nitrification liquid is deoxygenated, it is returned to the anoxic zone through the nitrification liquid reflux system. At this time, the nitrification liquid reflux system is installed in the oxygen removal zone.

[0015] A further technical solution is that the deoxidation zone is provided with a deoxidation treatment module for deoxidation of the nitrification liquid.

[0016] Furthermore, the deoxygenation treatment module is at least one of a deoxygenating agent, a nitrogen filling module or an anoxic biofilm module. Specifically, the nitrified liquid in the deoxygenation zone can be deoxygenated by adding a deoxygenating agent, filling nitrogen, or adding an anoxic biofilm module to the deoxygenation zone.

[0017] A further technical solution is that the deoxygenation treatment module is a second anoxic biofilm module, and the second anoxic biofilm module is arranged in the deoxygenation zone for deoxygenating the nitrification liquid.

[0018] In this solution, three partitions are used to separate the biochemical pool into a water inlet zone, an anaerobic zone, an aerobic zone and an oxygen elimination zone.

[0019] In some implementation schemes, the dissolved oxygen in the aerobic zone can be precisely controlled by linking an online dissolved oxygen monitoring device, an aeration device, and a PLC automatic control program. A specific aeration volume can also be set according to demand to control the dissolved oxygen in the aerobic zone within a specific range.

[0020] In some embodiments, the dissolved oxygen in the anoxic zone can be controlled at 0-0.5 mg / L by selecting different stirring devices and their operating modes and reducing the dissolved oxygen in the reflux nitrification liquid, thereby creating favorable conditions for the denitrification reaction.

[0021] In some embodiments, the nitrification liquid reflux system includes a reflux pump and a reflux pipeline. The reflux pump refluxes the nitrification liquid from the aerobic zone or the anoxic zone to the anoxic zone for denitrification. The reflux ratio is 100-400%, which can be adjusted according to demand.

[0022] A further technical solution is that the first anoxic biofilm module and the second anoxic biofilm module both include an anoxic module skeleton, a first aquatic plant landscape unit, an anoxic biofilm treatment unit and an anoxic stirring device, and the first aquatic plant landscape unit, the anoxic biofilm treatment unit and the anoxic stirring device are arranged on the anoxic module skeleton in sequence from top to bottom.

[0023] A further technical solution is that the aerobic biofilm module includes an aerobic module skeleton, a second aquatic plant landscape unit, an aerobic biofilm treatment unit and an aerobic aeration device, and the second aquatic plant landscape unit, the aerobic biofilm treatment unit and the aerobic aeration device are arranged on the aerobic module skeleton in sequence from top to bottom.

[0024] Furthermore, the skeleton of the anoxic module and the skeleton of the aerobic module are in the shape of a hollow rectangular parallelepiped, and are processed by one or more materials selected from stainless steel, plastic, and fiberglass, and the processing method is welding or assembly, etc., and are used to fix the first and second aquatic plant landscape units and install the anoxic and aerobic biofilm treatment units.

[0025] Furthermore, the first and second aquatic plant landscape units are both installed with floating plates, and the floating plates are provided with cultivation holes for planting aquatic plants with water purification functions to absorb C, N, and P pollutants in sewage and enhance the sewage treatment effect.

[0026] A further technical solution is that the anoxic biofilm treatment unit comprises a plurality of suspended sheet-like biofilm fillers and anoxic microbial inoculants arranged on the biofilm fillers.

[0027] The anoxic microbial agent is a specifically domesticated denitrifying functional bacterial community, which has the characteristics of highly efficient degradation of pollutants such as organic matter and total nitrogen.

[0028] A further technical solution is that the aerobic biofilm treatment unit comprises a plurality of suspended sheet-like biofilm fillers and an aerobic microbial agent arranged on the biofilm fillers.

[0029] The aerobic microbial agent is a specifically domesticated nitrifying functional bacterial group, which has the characteristics of highly efficient degradation of pollutants such as organic matter and ammonia nitrogen.

[0030] In some embodiments, the biofilm filler is made of one or more of polyester fiber, polypropylene, polyethylene, and polyurethane, which has the characteristics of large specific surface area, easy microbial attachment, and conducive to biofilm growth, and can efficiently enrich functional microbial flora.

[0031] In some embodiments, the biofilm filler is in sheet form with a thickness of 1-10 mm. The biofilm filler is suspended in the middle of the skeleton at a spacing of 2-50 mm, and a fixed width of air-water channel is formed between adjacent biofilm fillers, which can enhance the contact and mass transfer between the biofilm and the pollutants. In the anoxic biofilm treatment unit and the aerobic biofilm treatment unit, the filling rate of the biofilm filler is 20-70%.

[0032] In some embodiments, the anoxic zone is provided with an anoxic stirring device, which may be a gas stirring device, such as one or more of a microporous aerator, a tubular aerator, a vortex mixing aerator, a perforated tube, and a bubble stone; a mechanical stirring device may also be selected, such as one or more of a submersible flow propeller, a wave maker, and a submersible agitator.

[0033] Optionally, the anoxic stirring device may be installed at the lower part of the module frame of the anoxic biofilm module, or may be installed at the bottom of the anoxic zone.

[0034] Preferably, the anoxic stirring device is operated in a continuous or intermittent manner, and the operating frequency can be adjusted according to actual operating requirements.

[0035] In some embodiments, the aerobic zone is provided with an aerobic aeration device. The aerobic aeration device is a double-layer structure, the upper layer is arranged in a module projection center symmetrical type, and uses one or more of a microporous aerator, a tubular aerator, a vortex mixing aerator, a nano aeration tube, and a bubble stone; the lower layer aeration device is a perforated tube with a pore size of 1-6 mm.

[0036] Preferably, the aerobic aeration device can be installed at the lower part of the module frame of the aerobic biofilm module, or at the bottom of the aerobic zone.

[0037] Preferably, the aerobic aeration device operates in a continuous or intermittent manner, and the operating frequency can be adjusted according to actual operating requirements.

[0038] In some embodiments, the aerobic biofilm module and the anoxic biofilm module further include an energy system, which can be powered by a mains power system or a photovoltaic power generation system, wherein the photovoltaic power generation system includes a solar panel, a lead-acid battery, a charge and discharge controller, an inverter, a control cabinet, and the like.

[0039] A further technical solution is that the modular anoxic aerobic biofilm sewage treatment system also includes a pretreatment unit, which is arranged at the water inlet end of the biochemical pool body, and the pretreatment unit is connected to the water inlet area.

[0040] It should be noted that for turbid water bodies with more particulate impurities, the pretreatment unit can be a sand settling tank to remove sand and solid suspended matter in sewage, so as to avoid large particles in sewage causing wear and blockage to subsequent sewage treatment equipment; for sewage with low biodegradability, the pretreatment unit is a hydrolysis acidification tank to improve the biodegradability of sewage, convert high-molecular organic matter into small-molecular compounds, and reduce the difficulty of subsequent sewage treatment; for rural sewage and other problems with large fluctuations in water quality and quantity, the pretreatment unit is a regulating tank that can adjust the water quality and quantity of sewage, reduce the impact load of subsequent sewage treatment facilities, and provide a more stable treatment environment for the sewage treatment system. The setting of the pretreatment unit can be flexibly selected according to the actual water quality of the water body.

[0041] A further technical solution is that the modular anoxic aerobic biofilm wastewater treatment system further includes a deep treatment unit, and the deep treatment unit is arranged at the water outlet end of the biochemical pool body.

[0042] In case of too high concentration of suspended solids (SS) in the influent, the biochemical pool can reduce the SS concentration of the effluent by setting a deep treatment unit to ensure that the effluent meets the standard stably. The deep treatment unit can be a sand filter, a filter cloth filter, etc.

[0043] Compared with the prior art, the technical effects achieved by the embodiments of the present invention include:

[0044] The modular anoxic aerobic biofilm sewage treatment system provided by the utility model is a pure biofilm water treatment process system, which combines the biofilm method, AO process and plant absorption enhancement technology. The system can efficiently remove pollutants such as organic matter, ammonia nitrogen, nitrate nitrogen, etc., has a strong impact resistance to the influent water quality, and can operate stably under environmental conditions with large fluctuations in the influent load.

[0045] The sewage treatment system of the utility model has high biomass and microbial activity, and has the characteristics of high treatment efficiency, low sludge production, small footprint, simple operation and maintenance, and low operating cost. It is suitable for the treatment of low-pollution water bodies such as rural sewage. By combining the AO process and modular fixed biofilm technology, the system can improve the total nitrogen removal effect of sewage, and has the advantages of simple construction, compact structure, economical and convenient operation and maintenance, and stable effect. At the same time, there is no need to set up a sludge return system, which can further reduce the operating energy consumption.

[0046] In the modular anoxic aerobic biofilm sewage treatment system provided by the utility model, the anoxic biofilm module and the aerobic biofilm module adopt modular and standardized design ideas, and have the advantages of flexible application, simple construction and short construction period.

[0047] The utility model can enhance the anti-shock capability and stability of the system by combining with the pre-processing unit and the deep processing unit, and further ensure that the system can operate stably for a long time. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The accompanying drawings herein are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present utility model, and together with the description, are used to explain the principles of the present utility model.

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the utility model or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0050] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0051] Figure 1 This is a schematic structural diagram of a modular anoxic aerobic biofilm sewage treatment system provided in Example 1 of the utility model.

[0052] Figure 2This is a structural schematic diagram of a modular anoxic aerobic biofilm sewage treatment system provided in Example 2 of the utility model.

[0053] Figure 3 This is a structural schematic diagram of a modular anoxic aerobic biofilm sewage treatment system provided in Example 3 of the utility model.

[0054] Figure 4 This is a schematic structural diagram of the anoxic biofilm module provided by the utility model.

[0055] Figure 5 This is a schematic structural diagram of the aerobic biofilm module provided by the utility model.

[0056] Reference numerals

[0057] Pretreatment unit 40, deep treatment unit 50, biochemical pond body 30, first anoxic biofilm module 10, second anoxic biofilm module 11, aerobic biofilm module 20, water inlet area 31, anoxic area 32, aerobic area 33, oxygen elimination area 34, nitrification liquid reflux system 35, anoxic module skeleton 103, first aquatic plant landscape unit 101, anoxic biofilm treatment unit 102, anoxic stirring device 104, aerobic module skeleton 203, second aquatic plant landscape unit 201, aerobic biofilm treatment unit 202, aerobic aeration device 204. DETAILED DESCRIPTION

[0058] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments. Similar component numbers in the drawings represent similar components. Obviously, the embodiments to be described below are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0059] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0060] It should also be understood that the terms used in this utility model embodiment specification are only for the purpose of describing specific embodiments and are not intended to limit the utility model embodiments. As used in the utility model embodiment specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0061] Example 1

[0062] This embodiment provides a modular anoxic aerobic biofilm sewage treatment system suitable for treating low-pollution water bodies such as rural sewage and having a denitrification function.

[0063] like Figure 1 As shown, the modular anoxic aerobic biofilm wastewater treatment system includes a biochemical pool body 30, a first anoxic biofilm module 10, an aerobic biofilm module 20 and a nitrification liquid return system 35; according to the water flow direction, the biochemical pool body includes a water inlet area 31, anoxic area 32 and aerobic area 33 connected in sequence; wherein the water inlet area 31, the anoxic area 32 and the aerobic area 33 are separated into three different areas by two partitions. A first anoxic biofilm module 10 is installed in the anoxic area 32, and two aerobic biofilm modules 20 and a nitrification liquid return system 35 are installed in the aerobic area.

[0064] In this embodiment, the biochemical pool body 30 is a carbon steel anticorrosive tank body with a size of 3.8m×1.1m×1.4m (length×width×height). Among them, the water inlet area 31 has a size of 0.2m×1.1m×1.4m (length×width×height), the anoxic area 32 has a size of 1.2m×1.1m×1.4m (length×width×height), and the aerobic area 33 has a size of 2.4m×1.1m×1.4m (length×width×height).

[0065] In this embodiment, the aerobic zone 33 is designed to have a gradually weakened aeration intensity to reduce the impact of dissolved oxygen carried by the refluxed nitrification liquid on the anoxic environment of the anoxic zone 32. The nitrification liquid reflux system 35 is installed at the end of the aerobic zone outlet.

[0066] In this embodiment, the nitrification liquid reflux system 35 includes a reflux pump 351 and a reflux pipe 352. The reflux pump 351 is installed in the aerobic zone 33 to reflux the nitrification liquid in the aerobic zone 33 to the anoxic zone 32 for denitrification. The reflux ratio is 200%.

[0067] In this embodiment, the first anoxic biofilm module 10 is an anoxic biofilm solid support module filled with biofilm fillers, and is designed to be 1.0m×1.0m×1.0m (length×width×height). Figure 4 As shown, the anoxic biofilm immobilization module includes an anoxic module skeleton 103, a first aquatic plant landscape unit 101 arranged on the top of the anoxic module, an anoxic biofilm treatment unit 102 fixed in the middle of the module and an anoxic stirring device 104 fixed at the bottom of the module.

[0068] In this embodiment, the aerobic biofilm module 20 is a biofilm solidification module provided with a biofilm filler, and is designed to be 1.0m×1.0m×1.0m (length×width×height). Figure 5As shown, it includes an aerobic module skeleton 203, a second aquatic plant landscape unit 201 arranged on the top of the aerobic module, an aerobic biofilm treatment unit 202 fixed in the middle of the module and an aerobic aeration device 204 fixed at the bottom of the module.

[0069] In this embodiment, the anoxic module frame 103 and the aerobic module frame 203 are in a rectangular shape and are made of stainless steel by welding.

[0070] In this embodiment, the first aquatic plant landscape unit 101 and the second aquatic plant landscape unit 201 are both installed with floating plates, and cultivation holes are set on the floating plates to plant calamus with water purification function. While creating an ecological landscape, the plant roots can absorb and assimilate part of the C, N, and P pollutants in the sewage, thereby enhancing the sewage treatment effect.

[0071] In this embodiment, the anoxic biofilm treatment unit 102 and the aerobic biofilm treatment unit 202 both include biofilm fillers and microbial agents. The biofilm filler is made of polyester fiber, processed into a sheet structure with a thickness of 4 mm, and suspended in the first anoxic biofilm module 10 and the aerobic biofilm module 20 at a spacing of 16 mm. The filling rate of the filler is 20.0%. The anoxic functional bacterial agent is a functional bacterial group independently developed by the applicant for the directional domestication of COD and TN. The aerobic microbial agent is a functional bacterial group independently developed by the applicant for the directional domestication of COD and TN. + -N directed domestication of functional bacterial flora.

[0072] In this embodiment, the anoxic stirring device 104 is a perforated tube with a hole diameter of 5 mm. The perforated tube is a single-layer structure and is installed at the lower part of the module frame of the first anoxic biofilm module 10 .

[0073] In this embodiment, the operation mode of the anoxic stirring device 104 is intermittent aeration, and the start-stop cycle is aeration for 2 minutes and stop for 118 minutes, that is, stirring for 2 minutes every 120 minutes. This operation mode can not only fully contact the sewage in the anoxic zone 31 with the anoxic biofilm treatment unit 102, but also maintain the anoxic environment of the anoxic zone 32.

[0074] In this embodiment, the aerobic aeration device 204 is a double-layer structure, with 6 aerators arranged on the upper layer in a symmetrical arrangement with respect to the module projection center, and microporous aerators are selected; the lower aeration device is a perforated tube with a pore diameter of 4 mm, which is installed at the lower part of the module frame of the aerobic biofilm module 20.

[0075] In this embodiment, the operation mode of the aerobic aeration device 204 is continuous operation to provide a suitable aerobic environment for the nitrification reaction.

[0076] In this embodiment, the modular anoxic aerobic biofilm wastewater treatment system uses a photovoltaic power generation system for power supply (not shown in the figure).

[0077] The working principle of Example 1 of the utility model is: sewage first enters the first anoxic biofilm module 10 of the anoxic zone 32 through the water inlet area 31, and a denitrification reaction occurs in the anoxic zone 32, and nitrate is denitrified into nitrogen gas by using organic matter, and then enters the aerobic biofilm module 20 of the aerobic zone 33, and the organic matter is further removed by aeration-enhanced biological mass transfer, biofilm microbial biochemical degradation and plant absorption enhancement in the aerobic zone 33, and at the same time, a nitrification reaction occurs to convert ammonia nitrogen into nitrate, and the nitrification liquid reflux system 35 returns part of the water in the aerobic zone 33 to the anoxic zone 32, so as to promote the removal of total nitrogen in the sewage and ensure that the effluent meets the discharge standards, and the treated sewage is discharged from the modular anoxic aerobic biofilm sewage treatment system by overflow.

[0078] Example 2

[0079] like Figure 2 As shown, this embodiment provides a modular anoxic aerobic biofilm sewage treatment system suitable for treating low-pollution water bodies such as rural sewage and having a denitrification function. Different from Example 1, Example 2 is based on Example 1, and an oxygen removal zone 34 is added to the rear end of the aerobic zone 33 in the biochemical pool body 30 of the modular anoxic aerobic biofilm sewage system. The oxygen removal zone 34 is installed with a second anoxic biofilm module 11, and the nitrification liquid reflux system 35 is installed in the oxygen removal zone 34.

[0080] In this embodiment, the biochemical pool body 30 is a carbon steel anticorrosive tank body with a size of 5.0m×1.1m×1.4m (length×width×height). Among them, the water inlet area 31 has a size of 0.2m×1.1m×1.4m (length×width×height), the anoxic area 32 has a size of 1.2m×1.1m×1.4m (length×width×height), the aerobic area 33 has a size of 2.4m×1.1m×1.4m (length×width×height), and the deoxidation area 34 has a size of 1.2m×1.1m×1.4m (length×width×height).

[0081] In this embodiment, the aerobic zone 33 is designed to be uniformly aerated, and a deoxygenation zone 34 is set at the rear end of the aerobic zone 33. The deoxygenation method is to install a second anoxic biofilm module 11 in the deoxygenation zone 34, and utilize the biochemical action of microorganisms to reduce the DO of the reflux nitrification liquid, thereby reducing the impact of the dissolved oxygen carried by the reflux nitrification liquid on the anoxic environment of the anoxic zone 32.

[0082] In this embodiment, the second anoxic biofilm module 11 has the same structure as the first anoxic biofilm module 10 described in Example 1, and both are anoxic biofilm solid support modules filled with biofilm fillers, and are designed to be 1.0m×1.0m×1.0m (length×width×height). Figure 4 shown.

[0083] The working principle of Example 2 of the utility model is: sewage first enters the first anoxic biofilm module 10 of the anoxic zone 32 through the water inlet area 31, denitrification reaction occurs in the anoxic zone 32, and nitrate is denitrified into nitrogen gas by using organic matter, and then enters the aerobic biofilm module 20 of the aerobic zone 33, and organic matter is further removed in the aerobic zone 33 through aeration-enhanced biological mass transfer, biofilm microbial biochemical degradation and plant absorption enhancement, and nitrification reaction occurs to convert ammonia nitrogen into nitrate, and finally the effluent from the aerobic zone 33 enters the anoxic zone 34, and the nitrification liquid reflux system 35 returns part of the water in the anoxic zone 34 to the anoxic zone 32, so as to promote the removal of total nitrogen in the sewage and ensure that the effluent meets the discharge standards, and the treated sewage is discharged from the modular anoxic aerobic biofilm sewage treatment system by overflow.

[0084] Example 3

[0085] like Figure 3 As shown, this embodiment provides a modular anoxic aerobic biofilm sewage treatment system suitable for treating low-pollution water bodies such as rural sewage and having a denitrification function. Different from Example 2, Example 3 is based on Example 2, and a pretreatment unit 40 is added to the front end of the biochemical pool body 30 of the modular anoxic aerobic biofilm sewage system, and a deep treatment unit 50 is added to the rear end of the biochemical pool body 30, and the three functional units are connected in sequence.

[0086] In this embodiment, the pre-treatment unit 40 is a sand settling tank, which can effectively remove sand and larger suspended particles in sewage.

[0087] In this embodiment, the deep treatment unit 50 is a sand filter tank, which reduces suspended solids in effluent, enhances effluent stability, and ensures that effluent is stable and meets standards.

[0088] The working principle of Example 3 of the utility model is as follows: low-pollution water bodies such as rural sewage are passed into the grit chamber for pretreatment to remove large solid impurities and suspended matter in the sewage. Then the sewage overflows into the biochemical tank for biochemical treatment, and through the biofilm purification effect and plant absorption enhancement effect, the C, N, and P pollutants are removed efficiently and quickly. After the sewage is treated in the biochemical tank, it enters the sand filter tank for deep treatment to ensure that the effluent is stable and meets the standards.

[0089] The trial proved that the effluent water quality of this embodiment 3 can reach the first-class agricultural pollution standard of Guangdong Province (DB44), and the inlet and outlet water data are shown in Table 1.

[0090] Table 1 Inlet and outlet water quality indicators of the modular anoxic aerobic biofilm sewage treatment system of Example 3

[0091]

[0092]

[0093] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0094] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0095] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0096] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be connected, detachably connected, or integrated; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0097] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0098] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. 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 utility model. In this specification, the schematic representation of the above terms should not be understood as necessarily being directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification.

[0099] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is intended to include these modifications and variations.

[0100] The above is a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the utility model, and these modifications or replacements should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A modular anoxic aerobic biofilm wastewater treatment system, characterized in that: It includes a biochemical pool body, a first anoxic biofilm module, an aerobic biofilm module and a nitrification liquid reflux system; according to the water flow direction, the biochemical pool body includes a water inlet area, anoxic area and aerobic area connected in sequence; the first anoxic biofilm module is arranged in the anoxic area, and the aerobic biofilm module is arranged in the aerobic area; the nitrification liquid reflux system is arranged in the aerobic area, and the nitrification liquid reflux system is used to return the nitrification liquid to the anoxic area.

2. The modular anoxic aerobic biofilm wastewater treatment system according to claim 1 is characterized in that: The biochemical pool body also includes an oxygen removal zone; the oxygen removal zone is connected to the aerobic zone, and the nitrification liquid reflux system is arranged in the oxygen removal zone; the oxygen removal zone is used to perform oxygen removal treatment on the nitrification liquid, and the nitrification liquid reflux system is used to return the nitrification liquid after the oxygen removal treatment to the anoxic zone.

3. The modular anoxic aerobic biofilm wastewater treatment system according to claim 2 is characterized in that: The deoxidation zone is provided with a deoxidation treatment module for deoxidation of the nitrification liquid.

4. The modular anoxic aerobic biofilm wastewater treatment system according to claim 2 is characterized in that: The biochemical pool body is divided into a water inlet zone, an anaerobic zone, an aerobic zone and an oxygen elimination zone by using three partitions.

5. The modular anoxic aerobic biofilm wastewater treatment system according to claim 3 is characterized in that: The first anoxic biofilm module includes an anoxic module skeleton, a first aquatic plant landscape unit, an anoxic biofilm treatment unit and an anoxic stirring device. The first aquatic plant landscape unit, the anoxic biofilm treatment unit and the anoxic stirring device are arranged on the anoxic module skeleton in sequence from top to bottom.

6. The modular anoxic aerobic biofilm wastewater treatment system according to claim 5, characterized in that: The aerobic biofilm module comprises an aerobic module skeleton, a second aquatic plant landscape unit, an aerobic biofilm treatment unit and an aerobic aeration device, wherein the second aquatic plant landscape unit, the aerobic biofilm treatment unit and the aerobic aeration device are sequentially arranged on the aerobic module skeleton from top to bottom.

7. The modular anoxic aerobic biofilm wastewater treatment system according to claim 6, characterized in that: The anoxic biofilm treatment unit comprises a plurality of suspended sheet-like biofilm fillers and anoxic microbial inoculants arranged on the biofilm fillers.

8. The modular anoxic aerobic biofilm wastewater treatment system according to claim 6, characterized in that: The aerobic biofilm treatment unit comprises a plurality of suspended sheet-shaped biofilm fillers and an aerobic microbial agent arranged on the biofilm fillers.

9. The modular anoxic aerobic biofilm wastewater treatment system according to claim 1, characterized in that: It also includes a pretreatment unit, which is arranged at the water inlet end of the biochemical pool body and is connected to the water inlet area.

10. The modular anoxic aerobic biofilm wastewater treatment system according to claim 1, characterized in that: It also includes a deep processing unit, which is arranged at the water outlet end of the biochemical pool body.

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