Wastewater treatment system

Abstract

The embodiment of the utility model provides a wastewater treatment system which comprises a water inlet, a pipeline mixing unit, a sludge filtering device, an anoxic tank, an aerobic tank and a sedimentation tank which are connected through pipelines, the water inlet is arranged at the front stage of the pipeline mixing unit, the sludge filtering device is arranged at the rear stage of the pipeline mixing unit, and the anoxic tank is arranged at the rear stage of the pipeline mixing unit; the pipeline mixing unit comprises a first pipeline mixer, the first pipeline mixer comprises a first dosing port, and the first dosing port is used for being connected with a chemical phosphorus removal agent container to receive dosing of a chemical phosphorus removal agent; the sludge filtering device is used for filtering sludge in the output liquid, so that the liquid after sludge filtering is output to the anoxic tank. The domestic sewage treatment device has the beneficial effects that the domestic sewage is firstly subjected to chemical phosphorus removal through the pipeline mixing unit and then is subjected to biological phosphorus removal through the anoxic tank and the aerobic tank, the phosphorus removal effect is enhanced, and meanwhile, the domestic sewage subjected to chemical phosphorus removal is subjected to activated sludge dewatering through the sludge filtering device.

Description

Technical Field

[0001] The present disclosure relates to the field of environmental protection technologies, and particularly to a wastewater treatment system. Background Art

[0002] In China, the problem of rural sewage treatment has emerged as an urgent challenge for environmental protection. Rural sewage treatment has become one of the top priorities to be addressed promptly to cope with the increasingly severe environmental pressure. After rural domestic sewage is treated by local sewage treatment facilities, it is directly discharged into natural water bodies. Its discharge standards strictly follow the provisions of the Comprehensive Sewage Discharge Standard (DB3 / 9 - 2018). Among them, the discharge limit of total phosphorus (in terms of the TP index) is 0.5 mg / L. If it is a sensitive water area, it is even more stringent, limited to 0.3 mg / L, indicating extremely low requirements for phosphorus discharge thresholds. This requires rural sewage treatment facilities to maintain an efficient and stable operation state in order to meet the high - standard environmental protection emissions.

[0003] However, the efficient operation and management of rural sewage treatment facilities face difficulties. Due to the lack of daily supervision by professional personnel, the adjustment of key operations such as sludge age control and dissolved oxygen ratio and other parameters is prone to imbalance, which is extremely likely to cause the TP discharge to exceed the standard and fail to meet the strict environmental protection standards. Although biological treatment methods, such as the activated sludge method (including the sequencing batch and continuous - flow activated sludge methods), are widely used in wastewater treatment to remove organic matter and nutrient elements such as nitrogen and phosphorus, their phosphorus removal efficiency and stability are restricted by multiple factors.

[0004] In addition, in the process of dewatering after treatment by small - scale sewage treatment facilities, in related technologies, the sludge dewatering technologies adopted, such as plate - and - frame filter presses or spiral screw filter presses, all have drawbacks. The plate - and - frame filter press is time - consuming and laborious to clean, which is not conducive to daily maintenance. Although the spiral screw filter press has higher efficiency, the cost investment is relatively large, increasing the economic burden of facility operation. Summary of the Invention

[0005] In view of the above - mentioned disadvantages of the prior art, the purpose of the present disclosure is to provide a wastewater treatment system to solve the problems in the related technologies.

[0006] The first aspect of the present disclosure provides a wastewater treatment system, which includes an inlet, a pipeline mixing unit, a sludge filtration device, an anoxic tank, an aerobic tank, and a sedimentation tank connected by pipelines;

[0007] The inlet is arranged at the front stage of the pipeline mixing unit, the sludge filtration device is arranged at the rear stage of the pipeline mixing unit, and the anoxic tank is arranged at the rear stage of the pipeline mixing unit;

[0008] The pipeline mixing unit includes a first pipeline mixer, and the first pipeline mixer includes a first chemical dosing port, which is connected to a chemical dephosphorization agent container to receive the dosing of the chemical dephosphorization agent;

[0009] The sludge filtration device is used to filter the sludge in the output liquid so that the liquid after filtering the sludge is output to the anoxic tank.

[0010] Optionally, the pipeline mixing unit further includes a second pipeline mixer, and the second pipeline mixer includes a second chemical dosing port, which is connected to a flocculant container and receives the dosing of the flocculant.

[0011] Optionally, the second pipeline mixer is arranged at the downstream stage of the first pipeline mixer.

[0012] Optionally, the sludge filtration device includes: a sludge filtration mechanism for filtering sludge and an intermediate water tank, which is connected to the pipeline mixing unit and suspended in the intermediate water tank, and the intermediate water tank is connected to the anoxic tank through a pipeline.

[0013] Optionally, the sludge filtration mechanism includes: a geotextile bag.

[0014] Optionally, an adjustment tank is further arranged between the water inlet and the pipeline mixing unit, and domestic wastewater enters the adjustment tank through the water inlet and then flows into the pipeline mixing unit.

[0015] Optionally, a lift pump is arranged in the adjustment tank to pump the domestic sewage in the adjustment tank into the pipeline mixing unit.

[0016] Optionally, a grid channel is further included, which is arranged at the downstream stage of the water inlet to intercept the solids in the domestic sewage.

[0017] Optionally, the sedimentation tank includes: a sludge reflux pump;

[0018] The sludge reflux pump is connected to the anoxic tank and the sludge filtration device through pipelines to return the sludge generated in the anoxic tank and the aerobic tank and precipitated in the sedimentation tank to the anoxic tank and / or the sludge filtration device.

[0019] Optionally, the sedimentation tank further includes: an overflow weir, and the liquid after sedimentation treatment in the sedimentation tank flows out through the overflow weir.

[0020] The beneficial effects of the present disclosure: The domestic sewage is first subjected to chemical dephosphorization by the pipeline mixing unit, and then biological dephosphorization is carried out through the anoxic tank and the aerobic tank, which strengthens the dephosphorization effect. At the same time, the activated sludge of the domestic sewage after chemical dephosphorization is dehydrated by the sludge filtration device. Description of the Drawings

[0021] Figure 1 Show the structural block diagram of the wastewater treatment system in an embodiment of the present disclosure.

[0022] Figure 2 Show the structural block diagram of the wastewater treatment system in another embodiment of the present disclosure. Detailed implementation manners

[0023] The following uses specific specific examples to illustrate the implementation manners of the present disclosure. Those skilled in the art can easily understand other advantages and effects of the present disclosure from the information disclosed by the present disclosure. The present disclosure can also be implemented or applied through other different specific implementation manners. Various details in the present disclosure can also be modified or changed according to different viewpoints and application modules without departing from the spirit of the present disclosure. It should be noted that, without conflict, the embodiments and features in the embodiments of the present disclosure can be combined with each other.

[0024] The following takes the attached drawings as a reference and details the embodiments of the present disclosure so that those skilled in the art to which the present disclosure pertains can easily implement it. The present disclosure can be embodied in many different forms and is not limited to the embodiments described herein.

[0025] In the description of the present disclosure, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics represented in connection with the embodiment or example are included in at least one embodiment or example of the present disclosure. Moreover, the specific features, structures, materials, or characteristics represented can be combined in a suitable manner in any one or a group of embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples represented in the present disclosure and the features of different embodiments or examples.

[0026] In addition, the terms "first" and "second" are only used for the purpose of indication and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present disclosure, the meaning of "a group" is two or more, unless otherwise specifically defined.

[0027] In order to clearly illustrate the present disclosure, devices irrelevant to the description are omitted, and the same or similar components throughout the specification are given the same reference numerals.

[0028] Throughout the specification, when it is said that a device is "connected" to another device, this includes not only the case of "direct connection", but also the case of "indirect connection" where other elements are placed in between. Additionally, when it is said that a certain device "includes" a certain component, unless there is a particularly contrary record, it does not exclude other components, but means that other components may also be included.

[0029] Although in some examples the terms first, second, etc. are used herein to denote various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, the first interface and the second interface, etc. are indicated. Furthermore, as used herein, the singular forms "a", "an", and "the" are intended to also include the plural forms unless the context indicates otherwise. It should be further understood that the terms "comprising", "including" indicate the presence of features, steps, operations, elements, modules, items, kinds, and / or groups, but do not exclude the presence, occurrence, or addition of one or a group of other features, steps, operations, elements, modules, items, kinds, and / or groups. The terms "or" and "and / or" used herein are interpreted as inclusive, or meaning any one or any combination. Thus, "A, B, or C" or "A, B, and / or C" means "any one of the following: A; B; C; A and B; A and C; B and C; A, B, and C". An exception to this definition occurs only when the combination of elements, functions, steps, or operations is inherently mutually exclusive in some way.

[0030] The technical terms used herein are only for referring to specific embodiments and are not intended to limit the present disclosure. The singular forms used herein also include the plural forms as long as the statement does not clearly indicate the contrary meaning. The meaning of "including" used in the specification is to embody specific characteristics, regions, integers, steps, operations, elements, and / or components, and does not exclude the existence or addition of other characteristics, regions, integers, steps, operations, elements, and / or components.

[0031] Although not defined differently, including the technical terms and scientific terms used herein, all terms have the same meaning as generally understood by those skilled in the technical field to which the present disclosure pertains. Terms defined in commonly used dictionaries are additionally interpreted as having a meaning consistent with the relevant technical literature and the currently presented information, and should not be over-interpreted as ideal or overly formulaic meanings as long as they are not defined.

[0032] In the related art, in the treatment of domestic wastewater, the biological phosphorus removal method is usually adopted to remove phosphorus in domestic wastewater. The conventional biological treatment method can remove part of the phosphorus from the wastewater through the discharge and treatment of excess sludge, but the influencing factors of the biological treatment method are numerous and the corresponding phosphorus removal effect is limited.

[0033] In addition, in the process of dewatering after treatment by small sewage treatment facilities, in related technologies, the sludge dewatering technologies adopted, such as plate and frame filter presses or spiral filter presses, all have drawbacks. The plate and frame filter press is time-consuming and laborious to clean and time-consuming, which is not conducive to daily maintenance. Although the spiral filter press has higher efficiency, the cost input is relatively large, increasing the economic burden of facility operation.

[0034] In view of this, the wastewater treatment system of the present disclosure first performs chemical phosphorus removal on domestic sewage through the pipeline mixing unit 200, and then performs biological phosphorus removal through the anoxic tank 400 and the aerobic tank 500, strengthening the phosphorus removal effect. At the same time, the activated sludge of the domestic sewage after chemical phosphorus removal is dehydrated through the sludge filtration device 300. The wastewater treatment system of the present disclosure can treat sewage from households, communities, rural areas or small-scale sewage.

[0035] The first aspect of the present disclosure provides a wastewater treatment system, wherein Figure 1 In an example, it includes a water inlet 100, a pipeline mixing unit 200, a sludge filtration device 300, an anoxic tank 400, an aerobic tank 500 and a sedimentation tank 600 connected by pipelines;

[0036] The water inlet 100 is arranged at the front stage of the pipeline mixing unit 200, the sludge filtration device 300 is arranged at the rear stage of the pipeline mixing unit 200, and the anoxic tank 400 is arranged at the rear stage of the pipeline mixing unit 200;

[0037] The pipeline mixing unit 200 includes a first pipeline mixer 201, and the first pipeline mixer 201 includes a first chemical agent dosing port 2011, and the first chemical agent dosing port 2011 is connected to a chemical phosphorus removal agent container 2012 to receive the dosing of the chemical phosphorus removal agent;

[0038] The sludge filtration device 300 is used to filter the sludge in the output liquid so that the liquid after filtering the sludge is output to the anoxic tank 400.

[0039] Specifically, in some embodiments, domestic sewage flows in through the water inlet 100 and undergoes chemical treatment through the pipeline mixing unit 200. The domestic sewage can be agricultural sewage or urban sewage. The first pipeline mixer 201 is provided with a first chemical agent dosing port 2011, which is connected to the chemical phosphorus removal agent container 2012. At this stage, the dosing of the chemical phosphorus removal agent can be automatically controlled by an external automatic dosing device or the chemical phosphorus removal agent can also be manually dosed, and the dosing method can be selected according to the actual situation; the chemical phosphorus removal agent can quickly remove the refractory biodegradable phosphorus in the wastewater, greatly improving the phosphorus removal efficiency and at the same time reducing the subsequent biological treatment burden.

[0040] Subsequently, in the sludge filtration device 300, suspended solid impurities are intercepted through physical filtration techniques (such as high-efficiency filter screens or membranes), most of the sludge is separated, and only clean liquid water is allowed to flow to the anoxic tank 400, reducing the load of subsequent biological treatment and improving the overall treatment efficiency.

[0041] The anoxic tank 400 is used to treat the liquid filtered by the sludge filtration device 300. In the anoxic tank 400, the environment is designed to be anaerobic or with a very low micro-oxygen concentration, which is conducive to the growth and reproduction of specific microbial communities (anaerobic bacteria, such as denitrifying bacteria). These bacteria carry out denitrification in an anaerobic environment, converting nitrate (NO3-) in water into nitrogen gas (N2) or NO gas, achieving nitrogen removal. At the same time, some organic matter may also be converted into biogas, such as methane, etc., further removing the organic load. The denitrification process in the anoxic tank 400 creates conditions for the subsequent aerobic tank 500 because nitrification requires nitrate nitrogen as a raw material.

[0042] The aerobic tank 500 operates under sufficient oxygen supply to promote the activity of aerobic microorganisms. This stage includes two steps: nitridation (converting ammonia nitrogen into nitrite) and nitrification (converting nitrite into nitrate). Nitridation decomposes organic matter in water into carbon dioxide, water, and inorganic salts, while the nitrification process removes nitrogen and helps with the biological removal of phosphorus through polyphosphate accumulation (in the activated sludge).

[0043] The aerobic microorganisms or specific microbial communities in the anoxic tank 400 and the aerobic tank 500 live in the activated sludge and are used for biological treatment of domestic sewage. After treatment in the anoxic tank 400 and the aerobic tank 500, there may be activated sludge containing microorganisms in the water body. Therefore, it is necessary to further precipitate through the sedimentation tank 600 to ensure sludge sedimentation and separation, making the effluent meet the discharge standards.

[0044] Optionally, in Figure 2 the example, the pipeline mixing unit 200 further includes a second pipeline mixer 202. The second pipeline mixer 202 includes a second chemical dosing port 2021, and the second chemical dosing port 2021 is connected to a flocculant container 2022 and receives the dosing of the flocculant.

[0045] Specifically, in some embodiments, in addition to the original first pipeline mixer 201, a second pipeline mixer 202 is added. There is a second chemical dosing port 2021 inside the second pipeline mixer 202, which is connected to an external flocculant container 2022, and the dosage of the flocculant can be automatically or manually controlled as needed, ensuring the accurate dosing of the flocculant into the wastewater.

[0046] Optionally, in Figure 2 the example, the second pipeline mixer 202 is arranged at the downstream of the first pipeline mixer 201.

[0047] Specifically, the chemical phosphorus remover is used first to remove phosphorus in the water. The formed insoluble phosphate particles are relatively small and are easily captured by the subsequent flocculant. The phosphorus precipitate generated by the chemical phosphorus remover combines with the flocs formed by the flocculant, making the flocs larger, improving the precipitation efficiency, and accelerating the removal of phosphorus and suspended solids. Through the combination of the chemical phosphorus remover and the flocculant, not only the water body and colloids are effectively removed, but also the phosphorus content is reduced, overall improving the effluent quality and reducing the burden on subsequent biological treatment, creating more favorable conditions for the aerobic tank 500 and sedimentation tank 600. Therefore, the second pipeline relaxation period is set at the subsequent stage of the first pipeline mixer 201.

[0048] Optionally, in Figure 2 the example, the sludge filtration device 300 includes: a sludge filtration mechanism 302 for filtering sludge and an intermediate water tank 301, which is connected to the pipeline mixing unit 200, suspended in the intermediate water tank 301, and the intermediate water tank 301 is connected to the anoxic tank 400 through a pipeline.

[0049] Specifically, in some embodiments, the sludge filtration mechanism 302 adopts a physical or semi-automatic design, such as a sieve, a filter cloth bag or a membrane, for separating solid suspended matter (sludge) from the wastewater. When the sludge accumulates to a certain amount, the cleaning mechanism is automatically or manually triggered to start, such as flushing or sludge discharge operations, to ensure continuous filtration efficiency. The intermediate water tank 301 after the sludge filtration mechanism 302 serves as a transition zone to collect the filtered clarified water. The sludge is removed, and the water quality is preliminarily purified. The intermediate water body is smoothly transported to the anoxic tank 400 through a pipeline. At this time, most of the sludge has been removed from the water. After chemical treatment, it is beneficial for the biodegradation of aerobic microorganisms, further decomposing organic matter, improving the nitrogen and phosphorus removal efficiency, and ensuring the effluent standard.

[0050] Optionally, the sludge filtration mechanism 302 includes: a geotextile bag.

[0051] Specifically, as an example, the sludge filtration mechanism 302 can be a geotextile bag. After the wastewater is treated by the pipeline mixing unit 200, the mixture containing partial precipitation and suspended solids enters the intermediate water tank 301. The intermediate water tank 301 is between the pipeline mixing unit 200 and the anoxic tank 400, serving as a transition to ensure continuity. In the intermediate water tank 301, the suspension liquid will pass through the geotextile bag filtration mechanism. The geotextile bag cloth serves as a filtration layer to intercept and accumulate solid particles, such as sludge, fibers, etc., while water molecules freely pass through the bag pores to achieve solid-liquid separation. The filtered clean liquid (intermediate water) flows out from the geotextile bag filtration mechanism and is connected to the anoxic tank 400 through the pipeline of the intermediate water tank 301. At this time, most of the suspended solids have been removed from the water body, reducing the biological treatment burden on the anoxic tank 400 and optimizing the biological treatment effect. The geotextile bag filtration mechanism is convenient for regular inspection and replacement, avoiding blockage. The maintenance is simple. Just remove the geotextile bag, clean or replace it to maintain the filtration efficiency and extend the overall stable operation of the system.

[0052] Further, as an example, the geotextile bag can be made of high-tenacity polypropylene yarn. High-tenacity polypropylene, a high-molecular-weight lightweight polymer of polyethylene, has the advantages of chemical stability, corrosion resistance, mechanical strength, and toughness. High-tenacity polypropylene yarn, through special processing, further enhances the strength and flexibility of the material, ensuring durability in harsh environments. The high-tenacity polypropylene yarn is precisely woven into a grid structure, which not only ensures porosity for efficient filtration, allowing water molecules to pass through, but also has sufficient strength to intercept suspended solids such as sludge and fibers. When in contact with chemical substances in wastewater such as acidic or slightly acidic substances, due to its chemical stability, the high-tenacity polypropylene yarn is not eroded and maintains its filtration performance without degradation. During the filtration process, the geotextile bag woven from high-tenacity polypropylene yarn can withstand fluid pressure and solid impacts, is not easily damaged, and can maintain its structural integrity even under high solid loads.

[0053] Thanks to the physical properties of the polypropylene material, the geotextile bag is easy to clean. Surface deposits can be removed by physical brushing, soaking in chemical cleaning agents, etc., making it easy to restore filtration efficiency and having a long maintenance cycle.

[0054] Optionally, in Figure 2 the example, an adjustment tank 700 is also provided between the water inlet 100 and the pipe mixing unit 200. Domestic wastewater enters the adjustment tank 700 through the water inlet 100 and then flows into the pipe mixing unit 200.

[0055] Specifically, in some embodiments, the adjustment tank 700 is located between the water inlet 100 and the pipe mixing unit 200. Domestic wastewater enters through the water inlet 100 to collect wastewater, and the impurity content and quantity may fluctuate greatly, requiring pretreatment. The wastewater enters the adjustment tank 700. The tank body of the adjustment tank 700 has a certain volume of storage space, which can temporarily store and equalize the influent flow rate, balancing the subsequent treatment burden. Inside the tank, the wastewater begins to be initially statically settled, slowly stirred, or naturally degraded, reducing the sedimentation of suspended solids and alleviating the pressure on the pipe mixing unit 200.

[0056] In some embodiments, the adjustment tank 700 can be equipped with a flow control valve, a pump, etc., which are automatically adjusted according to the influent volume to ensure a uniform and stable inflow into the pipe mixing unit 200. The residence time and flow control of the adjustment tank 700 can be adjusted according to the water quality and treatment requirements, improving the overall treatment efficiency. After adjustment, the wastewater steadily flows through the pipe and enters the pipe mixing unit 200. At this time, the water quality and quantity are equalized, which is conducive to chemical, biological, or physical reactions, improving the treatment efficiency of removing suspended solids, disinfection, phosphorus removal, nitrogen and phosphorus removal, etc.

[0057] Optionally, in Figure 2 the example, a lift pump 701 is provided in the adjustment tank 700 for pumping the domestic sewage in the adjustment tank 700 into the pipe mixing unit 200.

[0058] Specifically, in some embodiments, the regulating tank 700 first receives domestic wastewater, which is input from the source through the water inlet 100, and various domestic sewage is collected in the tank. The lift pump 701 installed in the tank, when started, uses its mechanical force to extract and pressurize the sewage stored in the tank for transportation to the pipe mixing unit 200. The suction force and pressure design of the pump ensure the stable and efficient transfer of sewage, avoiding blockage or uneven overflow velocity. The sewage pumped by the lift pump 701 is sent to a pipe, and this pipe leads to the pipe mixing unit 200. The pipe can be designed with an appropriate diameter and slope to ensure smooth sewage flow without stagnation and reduce resistance.

[0059] As an example, the installation position of the lift pump 701 in the regulating tank 700 can be flexibly adjusted according to factors such as the tank body structure, the layout of the inlet and outlet pipes, the tank body size, and the water flow power demand to optimize the pump efficiency and maintenance convenience. The following are several possible installation situations:

[0060] Center position at the bottom end of the tank: The lift pump 701 is placed at the center of the bottom of the regulating tank 700, usually near the connection of the outlet pipe. Such a layout is conducive to directly sucking the bottom sediment, reducing sediment accumulation, and having a small pumping water power loss, which is suitable for deep tank bodies.

[0061] Wall-mounted installation on the side wall: The pump is fixed to the side of the tank wall through an extended bracket or hanging bracket, which is convenient for maintenance and repair, away from the bottom of the tank to reduce the influence of silt and sand, and is suitable for relatively shallow tanks or considering maintenance access restrictions

[0062] Corner layout: Located at the corner of the regulating tank 700, the lift pump 701 is placed at the corner of the tank body, saving space, facilitating the centralized layout of the pump outlet pipes, reducing the length of the pipelines in the tank, and being suitable for space-limited and compact designs.

[0063] Floating design: The lift pump 701 uses a floating body, floating under the water surface, fixed or floating up and down with the water level, automatically adjusting, reducing power consumption, and being suitable for scenarios with large fluctuations in the tank water level and without precise deep control requirements.

[0064] Multi-pump configuration: In the case of a large regulating tank 700 or high flow demand, multiple pumps are set, dispersed at different positions in the tank or in parallel, and can be controlled individually to flexibly adjust according to peak and off-peak periods to ensure efficiency.

[0065] Optionally, in Figure 2 the example, a grid channel 800 is also included, which is set at the rear stage of the water inlet 100 to intercept the solids in the domestic sewage through the grid channel 800.

[0066] Specifically, in some embodiments, domestic sewage enters through the inlet 100, carrying various suspended solids, impurities, fibers, debris flakes and other solids, and flows through the pipeline to the grid channel 800. The grid channel 800 is internally provided with a grid or fence, with an appropriately designed interval to intercept solids and achieve preliminary solid-liquid separation. The solids intercepted on the grid accumulate on the grid and need to be cleaned regularly. The fence is lifted by a manual or automated mechanical drive cleaning device to remove the intercepted objects and keep the water flow unobstructed.

[0067] Optionally, in Figure 2 the example, the sedimentation tank 600 includes: a sludge return pump 601;

[0068] The sludge return pump 601 is connected to the anoxic tank 400 and the sludge filtration device 300 through pipelines to return the sludge generated via the anoxic tank 400 and the aerobic tank 500 and sedimented in the sedimentation tank 600 to the anoxic tank 400 and / or the sludge filtration device 300.

[0069] Specifically, in some embodiments, a sludge return pump 601 is configured in the sedimentation tank 600 and is connected to the anoxic tank 400 and the sludge filtration device 300 through a pipeline system to form a closed-loop return path. Via the anoxic tank 400 and the aerobic tank 500, the activated sludge containing aerobic microorganisms generated in the biological treatment process precipitates. The activated sludge containing aerobic microorganisms is precipitated through the sedimentation tank 600, pumped by the return pump, and the microorganisms and activated sludge precipitate are sent back to the anoxic tank 400 for recycling to maintain the microbial activity, or sent to the sludge filtration device 300 for further treatment to achieve solid-liquid separation. The start and stop operation of the sludge return pump 601 can be automatically controlled, adjusted according to the sludge volume and activity requirements in the tank, to maintain the microbial balance in the system and improve the treatment efficiency.

[0070] As an example, the position setting of the sludge return pump 601 can be flexibly adjusted according to factors such as the specific structure of the tank body, treatment requirements, flow rate, and maintenance convenience to optimize the overall treatment efficiency. The following are several possible layout situations:

[0071] Bottom of the sedimentation tank 600: The pump is set near the outlet at the bottom of the sedimentation tank 600, which is convenient for directly extracting the sedimented and degraded sludge, reducing the disturbance of the agitated water body, and is suitable for tank bodies with obvious division between the sedimentation area and the water outlet area.

[0072] Middle area: Located in the middle of the sedimentation tank 600, the sludge return pump 601 is inserted into the sludge through a pipeline, which is convenient for evenly extracting the sedimented sludge.

[0073] Zoned setting: If the tank body is large, multiple pumps are set at different points in zones, with a pump in each zone and independent control. It is suitable for large-scale treatment, with flexible adjustment, zoned management, and improved efficiency.

[0074] Optionally, inFigure 2 In the example, the sedimentation tank 600 further includes: an overflow weir 602, and the liquid after sedimentation treatment in the sedimentation tank 600 flows out through the overflow weir 602.

[0075] Specifically, in some embodiments, the overflow weir 602 contributes to the solid-liquid separation process. Especially in the sedimentation tank 600, the overflow weir 602 can cause the clear water to overflow, while the settled solids or sludge remain at the bottom of the tank, which is beneficial for subsequent sludge collection and improves the quality of the clear water. The height and angle of the overflow weir 602 are adapted to self-adjust the water level, ensuring a stable overflow rate, without excessive or blocked overflow, and maintaining a balanced output of the water body.

[0076] As an example, the position setting of the overflow weir 602 can be flexibly adjusted according to factors such as the specific structure of the tank body, treatment requirements, flow rate, and maintenance convenience, so as to optimize the overall treatment efficiency. The following are several possible arrangement situations:

[0077] Overflow weir 602 at the edge of the tank: Set along the tank wall, usually along the length edge of the tank, with natural overflow, stable water level control, suitable for a wide horizontal area, easy to maintain, and the width of the weir can be adjusted.

[0078] Multi-stage cascade: In a stepped form, with a multi-stage cascaded overflow weir 602, controlling the water level step by step, suitable for large gradient flow rate changes, fine adjustment, multi-stage adjustment, but with a complex structure.

[0079] The above embodiments are only illustrative of the principles and effects of the present disclosure, and are not used to limit the present disclosure. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present disclosure. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present disclosure should still be covered by the protection scope of the present disclosure.

Claims

1. A wastewater treatment system, characterized in that: It includes a water inlet, a pipeline mixing unit, a sludge filtering device, anoxic tank, aerobic tank and a sedimentation tank connected by pipelines; The water inlet is arranged at the front stage of the pipeline mixing unit, the sludge filtering device is arranged at the rear stage of the pipeline mixing unit, and the anoxic tank is arranged at the rear stage of the pipeline mixing unit; The pipeline mixing unit comprises a first pipeline mixer, the first pipeline mixer comprises a first dosing port, and the first dosing port is connected to a chemical dephosphorization agent container to receive the chemical dephosphorization agent; The sludge filtering device is used to filter the sludge in the output liquid, so that the liquid after the sludge is filtered is output to the anoxic tank.

2. The wastewater treatment system according to claim 1, characterized in that: The pipeline mixing unit further comprises a second pipeline mixer, wherein the second pipeline mixer comprises a second drug-dosing port, and the second drug-dosing port is connected to a flocculant container and receives the dosing of flocculant.

3. The wastewater treatment system according to claim 2, characterized in that: The second pipeline mixer is arranged at a subsequent stage of the first pipeline mixer.

4. The wastewater treatment system according to claim 1, characterized in that: The sludge filtering device comprises: a sludge filtering mechanism for filtering sludge and an intermediate water pool, which is connected to the pipeline mixing unit and suspended in the intermediate water pool, and the intermediate water pool pipeline is connected to the anoxic pool.

5. The wastewater treatment system according to claim 4, characterized in that: The sludge filtering mechanism comprises: a geobag.

6. The wastewater treatment system according to claim 1, characterized in that: A regulating tank is also provided between the water inlet and the pipeline mixing unit. Domestic wastewater enters the regulating tank through the water inlet and then flows into the pipeline mixing unit.

7. The wastewater treatment system according to claim 6, characterized in that: The regulating tank is provided with a lifting pump for pumping the domestic sewage in the regulating tank into the pipeline mixing unit.

8. The wastewater treatment system according to claim 1, characterized in that: It also includes a screen channel, which is arranged at the rear stage of the water inlet, and the solid matter in the domestic sewage is intercepted by the screen channel.

9. The wastewater treatment system according to claim 1, characterized in that: The sedimentation tank comprises: a sludge return pump; The sludge return pump is connected to the anoxic tank and the sludge filtering device through a pipeline to return the sludge produced by the anoxic tank and the aerobic tank and precipitated in the sedimentation tank to the anoxic tank and / or the sludge filtering device.

10. The wastewater treatment system according to claim 1, characterized in that: The sedimentation tank further comprises an overflow weir, through which the liquid after sedimentation treatment in the sedimentation tank flows out.

Images