Urban stormwater and sewage precision interception, storage and rapid purification system and method

Abstract

This invention provides a precise interception, storage, and rapid purification system and method for urban stormwater and sewage, relating to the field of sewage treatment technology. The system includes: a precise interception and storage device for intercepting and regulating stormwater and sewage; a sand and slag co-removal device for removing sand and slag from stormwater and sewage; a rapid purification device employing a combination of stirring coagulation, stirring flocculation, and disk separation to achieve rapid purification of stormwater and sewage; a biological treatment device for removing ammonia nitrogen, COD, and total nitrogen from stormwater and sewage; and a sterilization and disinfection device for sterilizing and disinfecting stormwater and sewage. This method utilizes the aforementioned system. By incorporating the precise interception and storage device, the sand and slag co-removal device, the rapid purification device, the biological treatment device, and the sterilization and disinfection device, the impact of rainfall pollution on the urban water environment is effectively reduced, alleviating the problems of post-rainwater water quality deterioration and the recurrence of black and foul odors.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, and in particular to a system and method for precise interception, storage and rapid purification of urban rainwater and sewage. Background Technology

[0002] In response to the problem of uncontrollable rainfall pollution and frequent post-rain blackening and foul odors in my country, this study investigates the composition characteristics of urban rainfall pollutants and high-flux rainwater and sewage precise interception, storage, and rapid purification technologies. The aim is to develop precise interception, storage, and rapid purification technologies and equipment for urban rainwater and sewage that are suitable for China's national conditions. This can effectively reduce the impact of rainfall pollution on the urban water environment and alleviate the problems of post-rain water quality deterioration and blackening and foul odors. Summary of the Invention

[0003] In response to the above situation, the present invention provides a precise interception, storage and rapid purification system and method for urban rainwater and sewage, aiming to develop a precise interception, storage and rapid purification technology and equipment for urban rainwater and sewage suitable for national conditions, so as to effectively reduce the impact of rainfall pollution on the urban water environment and alleviate the problems of water quality deterioration, blackening and odor recurrence after rain.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] In a first aspect, the present invention provides a precise interception, storage, and rapid purification system for urban stormwater and sewage, comprising:

[0006] Precision interception and storage devices are used to intercept and regulate rainwater and sewage.

[0007] A sand and slag removal device is used to remove sand and slag from rainwater and sewage first.

[0008] The rapid purification device uses a combination of stirring coagulation, stirring flocculation, and disk separation to achieve rapid purification of rainwater and sewage.

[0009] Biological treatment units are used to remove ammonia nitrogen, COD, and total nitrogen from rainwater and sewage.

[0010] Sterilization and disinfection device, used to sterilize and disinfect rainwater and sewage.

[0011] In some embodiments of the present invention, the precise water storage device includes:

[0012] A rainwater pipe connected to a first hydraulic flow control valve is used to transport rainwater to an interception tank;

[0013] The stormwater and sewage pipes connected to the interceptor pool are equipped with a second hydraulic flow regulating valve; the stormwater and sewage pipes include sewage pipes and combined pipes, the sewage pipes are adapted to the stormwater and sewage separate drainage system; the combined pipes are adapted to the stormwater and sewage combined drainage system.

[0014] The interception tank is equipped with a first submersible sewage pump and an overflow pipe, and a constant flow gate valve is connected to the overflow pipe;

[0015] The regulating tank is connected to the intercepting tank via an openable and closable valve structure; the regulating tank adopts a tiered compartmentalized structure, with rainwater and sewage flowing sequentially through each compartment of the regulating tank.

[0016] In some embodiments of the present invention, the rapid purification device includes:

[0017] The coagulation mechanism includes a primary mixing coagulation zone and a secondary mixing flocculation zone connected in sequence. The primary mixing coagulation zone achieves efficient coagulation of rainwater and sewage after treatment by the sand and slag removal device through mixing coagulation. The secondary mixing flocculation zone achieves efficient flocculation of rainwater and sewage through mixing flocculation.

[0018] A magnetic separation mechanism is used to separate magnetic flocs from rainwater and sewage that have been purified by a coagulation mechanism.

[0019] In some embodiments of the present invention, multiple stirring blades are arranged from top to bottom in the secondary stirring flocculation zone, and the stirring range of each stirring blade gradually increases from top to bottom.

[0020] In some embodiments of the present invention, an agitator and a guide tube are provided in the primary mixing and coagulation zone; the agitator is provided with multiple blades along its axial direction and is located inside the guide tube; both the upper and lower ends of the guide tube are open, and the upper diameter of the guide tube is smaller than its lower diameter.

[0021] In some embodiments of the present invention, the magnetic separation mechanism includes:

[0022] The flow channel connects to the secondary stirring and flocculation zone;

[0023] The disk is rotatably positioned in the flow channel to adsorb magnetic flocs containing magnetic powder;

[0024] Scraper strips, located near the outer layer of the disk, are used to work with the rotating disk to scrape off magnetic lint.

[0025] Screw conveyors are used to transport magnetic flocs scraped off the disk by scraper bars;

[0026] The disk has a multi-layered hollow structure, and a water outlet pipe is set along its axis. Rainwater and sewage in the channel are filtered through each layer of the disk from the outside to the inside and then discharged from the water outlet pipe.

[0027] In some embodiments of the present invention, the coagulation mechanism further includes a baffle mixing zone, in which multiple baffles are staggered and arranged, and the baffle mixing zone and the primary stirring coagulation zone are connected in sequence.

[0028] In some embodiments of the present invention, the biological treatment device includes:

[0029] The intermediate water tank is connected to the inlet of the distribution tank via a booster pump;

[0030] The nitrifying biological filter includes, from top to bottom, a water distribution tank, nitrifying filter media, and a first support layer; the inlet of the water distribution tank is connected to a rapid purification device; and it also includes an outlet tank for draining water from the nitrifying biological filter.

[0031] The self-atrophic denitrification filter includes, from top to bottom, a water distribution component, a denitrification filter media, a second support layer, and a denitrification drainage pipe; the inlet of the water distribution component is connected to the outlet of the outlet tank.

[0032] The first support layer includes a first filter brick with a smooth material; the upper part of the autotrophic denitrification filter is connected to a nitrogen removal overflow pipe, and the outlet of the nitrogen removal overflow pipe is connected to the intermediate water tank.

[0033] In some embodiments of the present invention, the biological treatment device further includes:

[0034] Perforated aeration pipes are installed in the first support layer and connected to an intelligent variable frequency fan;

[0035] The second backwash water pipe has its outlet located below the second support layer; the second support layer includes a second filter brick made of smooth material.

[0036] Backwash water pump, used to connect the rapid purification device and the second backwash water pipe;

[0037] The second backwash pipe is located below the second support layer and is connected to the intelligent variable frequency fan.

[0038] Secondly, the present invention provides a method for precise interception, storage, and rapid purification of urban stormwater and sewage, which utilizes the aforementioned system for precise interception, storage, and rapid purification of urban stormwater and sewage, and mainly includes the following steps:

[0039] Step S1: Precisely intercept and regulate rainwater and sewage;

[0040] Step S2: Remove sand from the intercepted rainwater and sewage;

[0041] Step S3: Remove slag from the rainwater and sewage after sand removal;

[0042] Step S4: Add the agent to the rainwater and sewage after sludge removal and perform non-powered mixing;

[0043] Step S5: Perform primary mechanical mixing on the rainwater and sewage after non-powered mixing;

[0044] Step S6: Perform secondary mechanical mixing on the rainwater and sewage after primary mechanical mixing;

[0045] Step S7: Perform magnetic separation on the rainwater and sewage after two-stage mechanical stirring; perform magnetic recovery on the magnetic flocs obtained after magnetic separation;

[0046] Step S8: After magnetic separation, the rainwater and sewage are treated to remove ammonia nitrogen and COD, then the total nitrogen is removed, followed by sterilization and disinfection, and finally discharged into the receiving water body or ecological replenishment water.

[0047] The embodiments of the present invention have at least the following advantages or beneficial effects:

[0048] By installing precise interception and storage devices, sand and slag co-removal devices, rapid purification devices, biological treatment devices, and sterilization and disinfection devices, the impact of rainfall pollution on the urban water environment has been effectively reduced, and the problems of water quality deterioration and blackening and odor recurrence after rain have been alleviated.

[0049] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0050] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of 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.

[0051] Figure 1 A schematic diagram of a system for the precise interception, storage, and rapid purification of urban rainwater and sewage.

[0052] Figure 2 A schematic diagram of the structure of the precision interception and storage device and the sand and slag co-removal device;

[0053] Figure 3 This is a schematic diagram of the rapid purification device;

[0054] Figure 4 This is a schematic diagram of the structure of a biological treatment device and a sterilization and disinfection device;

[0055] Figure 5 A flowchart illustrating a method for precise interception, storage, and rapid purification of urban stormwater and sewage.

[0056] icon:

[0057] 1-Precision interception and storage device; 11-Rainwater pipe; 111-First hydraulic flow regulating valve; 12-Rainwater and sewage pipe; 121-Second hydraulic flow regulating valve; 13-Interception tank; 131-First submersible sewage pump; 14-Storage tank; 141-Valve structure; 142-Second submersible sewage pump; 15-Overflow pipe; 151-Gate valve; 16-Intelligent control cabinet.

[0058] 2-Sand and slag co-removal device; 21-Cyclone separator; 211-Inlet of cyclone separator; 212-Outlet of cyclone separator; 213-Grit settling port of cyclone separator; 22-Sand-water separator; 221-Sand-water inlet of sand-water separator; 222-Overflow port of sand-water separator; 23-Fine filtration and separation device; 231-Drainage port of fine filtration and separation device; 24-Screw press.

[0059] 3-Rapid purification device; 311-Pipeline mixer; 312-Dosing and mixing tank; 313-Variable frequency dosing pump; 321-Primary mixing and coagulation zone; 3211-Agitator; 3212-Flow guide tube; 322-Secondary mixing and flocculation zone; 341-Flow channel; 342-Disk disk; 3421-Outlet pipe; 343-Scraper strip; 344-Screw conveyor; 361-High-speed deflocculator; 362-Magnetic drum; 363-Magnetic powder mixing box; 364-Magnetic powder dosing pump; 365-Scraper; 37-Baffle mixing zone; 371-Baffle plate; 38-Rapid purification control cabinet; 39-Online water quality monitor.

[0060] 4-Biological treatment unit; 41-Intermediate water tank; 42-Lift pump; 43-Nitrifying biological filter; 431-Water distribution tank; 432-Nitrifying filter media; 433-First support layer; 434-Effluent tank; 44-Autotrophic denitrifying filter; 441-Water distribution assembly; 442-Denitrifying filter media; 443-Second support layer; 444-Denitrification drainage pipe; 451-Perforated aeration pipe; 452-Intelligent variable frequency blower; 461-First backwash water pipe; 462-Second backwash water pipe; 463-Backwash water pump; 464-First backwash air pipe; 465-Second backwash air pipe.

[0061] 51-Ultraviolet sterilizer. Detailed Implementation

[0062] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the embodiments of the invention.

[0063] In the description of the embodiments of the present invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer", "axial", "radial", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the present invention.

[0064] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of the present invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0065] In the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention according to the specific circumstances.

[0066] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0067] Example

[0068] Firstly, please refer to Figures 1-4 This embodiment provides a precise interception and rapid purification system for urban rainwater and sewage, including a precise interception and storage device 1, a sand and slag co-removal device 2, a rapid purification device 3, a biological treatment device 4, and a sterilization and disinfection device.

[0069] The precision interception and storage device 1 is used to intercept and regulate rainwater and sewage (urban rainwater and sewage); the precision interception and storage device 1 includes rainwater pipe 11, rainwater and sewage pipe 12, interception pool 13 and regulation pool 14.

[0070] The rainwater pipe 11 is connected to the intercepting pool 13 and is used to transport rainwater into the intercepting pool 13. The rainwater pipe 11 is connected to a first hydraulic flow regulating valve 111.

[0071] The stormwater and sewage pipe 12 is connected to a second hydraulic flow regulating valve 121; the stormwater and sewage pipe 12 includes a sewage pipe and a combined pipe; the sewage pipe is adapted to the stormwater and sewage separation drainage system and is used to transport sewage to the intercepting tank 13; the combined pipe is adapted to the stormwater and sewage combined drainage system and is used to transport the mixed stormwater and sewage to the intercepting tank 13.

[0072] A first submersible sewage pump 131 is installed at the bottom of the intercepting pool 13 for draining water from the intercepting pool 13.

[0073] The regulating reservoir 14 and the intercepting reservoir 13 are connected by an openable and closable valve structure 141.

[0074] In a specific implementation scenario, the regulating tank 14 adopts a tiered compartmentalized structure, comprising multiple compartments (not shown in the figure). Rainwater and sewage flow overflow through each compartment in sequence to extend the residence time of water in the regulating tank 14, allowing larger suspended solids to preferentially settle in the front compartment of the regulating tank 14. The total amount of sediment is classified, enabling proactive matching and adjustment of the effluent conditions, reducing the impact of water volume and quality fluctuations on the stable operation of downstream equipment and structures.

[0075] In a specific implementation scenario, the valve structure 141 includes a hydraulically operated overflow weir. A second submersible sewage pump 142 is installed at the bottom of the storage tank 14. The second submersible sewage pump 142 is used to transport rainwater and sewage in the storage tank 14 to the intercepting tank 13 at the front end after the rainfall stops.

[0076] The precision interception and storage device 1 also includes an overflow pipe 15, to which a gate valve 151 is connected. The overflow pipe 15 is located in the interception pool 13. During the later stages of rainfall, the water quality in the interception pool 13 is relatively good (the water quality of rainwater is relatively good during the later stages of rainfall). If the regulating pool 14 is full, the water in the interception pool 13 can overflow directly into the receiving water body via the river. In a specific implementation scenario, the gate valve 151 is a constant flow gate valve 151 to create a slow flow condition, preventing the river channel from being impacted by excessive flow and causing the riverbed sediment to be resuspended, thereby causing secondary pollution.

[0077] The precision interception and storage device 1 also includes an intelligent control cabinet 16. The intelligent control cabinet 16 is used to automatically control the opening degree of the first hydraulic flow regulating valve 111 and the second hydraulic flow regulating valve 121 and the start and stop of the first submersible sewage pump 131 based on the COD and SS content of the incoming water obtained by online monitoring upstream of the precision interception and storage device 1. It also automatically controls the opening degree of the gate valve 151 based on the liquid level in the interception tank 13 obtained by online monitoring.

[0078] The working principle of the precision storage interception device 1 is as follows:

[0079] In the early stages of rainfall with high pollutant concentrations or when combined sewer overflow pollution is severe (COD≥200 mg / L or SS≥300 mg / L), open the first hydraulic flow regulating valve 111 and the second hydraulic flow regulating valve 121, close the gate valve 151 and the first submersible sewage pump 131, open the valve structure 141 leading to the storage tank 14, and temporarily store the rainwater and sewage with high pollutant concentrations into the storage tank 14.

[0080] During the later stages of rainfall when pollutant concentrations are low (COD < 200 mg / L or SS < 300 mg / L), the first hydraulic flow regulating valve 111 and the second hydraulic flow regulating valve 121 are opened, the valve structure 141 leading to the storage tank 14 is closed, the first submersible sewage pump 131 is opened, and the rainwater and sewage are discharged into the subsequent sand and slag co-removal device 2 for treatment.

[0081] At the end of the rainfall period (SS≤30mg / L), open the first hydraulic flow regulating valve 111, the second hydraulic flow regulating valve 121 and the gate valve 151, close the first submersible sewage pump 131 and the valve structure 141, and directly replenish the clean rainwater in the interception pool 13 to the receiving water body or for resource utilization through the overflow pipe 15.

[0082] After rain or on a sunny day, valve structure 141 is closed, and the rainwater and sewage in the storage tank 14 are sent to the intercepting tank 13 or the sand and slag co-removal device 2 through the second submersible sewage pump 142 to meet the operational needs after rain or on a sunny day. If there is domestic sewage discharge on a sunny day due to insufficient treatment capacity of the nearby sewage treatment plant or due to mixed or incorrect pipe connections, the first hydraulic flow regulating valve 111, the second hydraulic flow regulating valve 121 and the first submersible sewage pump 131 are opened, valve structure 141 is closed, and the rainwater and sewage in the intercepting tank 13 are discharged into the subsequent sand and slag co-removal device 2 for treatment.

[0083] The first hydraulic flow regulating valve 111 and the second hydraulic flow regulating valve 121 can automatically adjust the opening degree of each flow regulating valve according to the online monitoring liquid level value in the intercepting tank 13 to maintain the stability of the water level in the intercepting tank 13; when the valve structure 141 needs to be opened, it can automatically adjust the opening degree of the valve structure 141 according to the online monitoring liquid level value in the regulating tank 14 during the opening period to maintain the stability of the water level in the regulating tank 14.

[0084] Based on the above, the precise water storage device 1 has at least the following beneficial effects:

[0085] I. By setting up the precise interception and storage device 1, the impact of rainfall pollution on the urban water environment has been effectively reduced, and the problems of water quality deterioration and blackening and odor after rain have been alleviated.

[0086] Second, it can adapt to both separate stormwater and sewage drainage systems and combined stormwater and sewage drainage systems.

[0087] Third, in the later stages of rainfall, the water quality in the interception pool 13 is relatively good. After opening the gate valve 151, the water in the interception pool 13 can overflow directly into the receiving water body through the river channel.

[0088] Fourth, the gate valve 151 is a constant flow gate valve 151. When the intercepting pool 13 overflows, it can create a slow flow condition to prevent the river channel from being impacted by the excessive flow and the river bottom sediment from being resuspended, thereby avoiding secondary pollution.

[0089] V. Through the intelligent control cabinet 16 and the supporting online monitoring equipment, the automatic control of the first hydraulic flow regulating valve 111, the second hydraulic flow regulating valve 121, the first submersible sewage pump 131, the valve structure 141 and the gate valve 151 can be realized.

[0090] VI. It takes into account the operational needs of both sunny and rainy days.

[0091] The sand and slag co-removal device 2 is used to remove sand and slag from rainwater and sewage first. Sand refers to sedimentable inorganic particles, and slag refers to floating or suspended impurities. The sand and slag co-removal device 2 includes a cyclone separator 21, a sand-water separator 22, a fine filtration separator 23, and a screw press 24.

[0092] The cyclone separator 21 has an inlet and an outlet at the top and a sedimentation port at the bottom. The inlet 211 of the cyclone separator is connected to the first submersible sludge pump 131 via a pipe. The outlet 212 of the cyclone separator is connected to the inlet of the fine filtration separator 23 via a pipe. The cyclone separator can effectively separate and remove coarse sand and some fine sand.

[0093] The sand-water separator 22 has a sand-water inlet at the top, an overflow outlet at the top, and a sand discharge outlet at the bottom; the overflow outlet 222 of the sand-water separator is connected to the regulating tank 14; the sand-water inlet 221 of the sand-water separator is connected to the sand settling outlet 213 of the cyclone separator.

[0094] The inlet of the fine filtration and separation device 23 is connected to the outlet 212 of the cyclone separator; the outlet 231 of the fine filtration and separation device is connected to the rapid purification device 3. In a specific implementation scenario, the fine filtration and separation device 23 includes a perforated plate screen device, which can effectively intercept and filter floating or suspended impurities and fine slag.

[0095] The screw press 24 is connected to the slag discharge port of the perforated plate grid equipment. The weight and volume of the intercepted floating or suspended impurities and fine slag are greatly reduced after being pressed by the screw press 24, which facilitates subsequent slag discharge treatment.

[0096] The working principle of the sand and slag co-removal device 2 is as follows:

[0097] The rainwater and sewage in the interception tank 13 are sent to the hydrocyclone separator 21 by the first submersible sewage pump 131. The hydrocyclone separator 21 rotates to separate coarse sand and some fine sand by centrifugal force (provided by the first submersible sewage pump 131). The coarse sand and some fine sand enter the sand-water separator 22 and settle. The supernatant formed by the sedimentation flows back to the storage tank 14. The rainwater and sewage entering the fine filtration separator 23 from the outlet 212 of the hydrocyclone separator are discharged after being filtered by the fine filtration separator 23. The floating or suspended impurities and fine slag intercepted by the fine filtration separator 23 enter the screw press 24 for pressing.

[0098] Based on the above, the sand and slag co-removal device 2 has at least the following beneficial effects:

[0099] In response to the current situation where initial rainwater and overflow sewage have high sand and slag content and are difficult to remove, the sand and slag co-removal device 2 integrates strong cyclone technology (cyclone separator 21), sand-water separation technology (sand-water separator 22), and perforated plate interception technology (fine filtration separation device 23). It adopts a method of removing sand first and then slag for urban rainwater and sewage, which can effectively pre-treat urban rainwater and sewage, alleviate the clogging and wear problems of downstream purification equipment for urban rainwater and sewage, improve the comprehensive treatment capacity of the pre-treatment stage, and has positive significance for improving the treatment efficiency of urban rainwater and sewage.

[0100] The rapid purification device 3 adopts a combination of stirring coagulation, stirring flocculation and magnetic separation to achieve rapid purification of rainwater and sewage; the rapid purification device 3 includes a mixing and dosing mechanism, a coagulation mechanism, a magnetic separation mechanism and a magnetic recovery mechanism.

[0101] The mixing and dosing mechanism includes a pipeline mixer 311, a dosing mixing tank 312, and a variable frequency dosing pump 313. The pipeline mixer 311 is connected to the outlet of the fine filtration and separation equipment 23. The dosing mixing tank 312 sends the coagulant into the pipeline mixer 311 through the variable frequency dosing pump 313 to initially mix with the rainwater and sewage treated by the sand and slag co-removal device 2.

[0102] In a specific implementation scenario, the pipe mixer 311 has multiple spiral structures inside to improve the mixing effect of the pipe mixer 311.

[0103] The coagulation mechanism includes a primary mixing coagulation zone 321 and a secondary mixing flocculation zone 322 connected in sequence.

[0104] The primary mixing coagulation zone 321 is connected to the pipeline mixer 311; a mixer 3211 and a guide tube 3212 are coaxially arranged in the primary mixing coagulation zone 321; the mixer 3211 has multiple blades arranged along its axial direction and is located inside the guide tube 3212; both the upper and lower ends of the guide tube 3212 are open, and the upper diameter of the guide tube 3212 is smaller than its lower diameter. Under the action of mechanical stirring, radial flow and axial flow can be formed in the guide tube 3212, which improves the turbulence of the water flow. The turbulent movement in the primary mixing coagulation zone 321 is more intense, which maximizes the utilization of stirring energy and thus improves the coagulation effect.

[0105] The coagulation mechanism also includes a baffle mixing zone 37, and a pipe mixer 311 is connected to the baffle mixing zone 37. The baffle mixing zone 37, the primary stirring coagulation zone 321, and the secondary stirring flocculation zone 322 are connected in sequence. Multiple baffles 371 are staggered in the baffle mixing zone 37 to achieve non-powered baffle mixing, which improves the turbulence of the water flow and makes the turbulent movement in the primary stirring coagulation zone 321 and the secondary stirring flocculation zone 322 more intense, which is conducive to the collision and adhesion of floc particles to form magnetic flocs.

[0106] In a specific implementation scenario, the outlet of the pipe mixer 311 is connected to the lower part of the baffle mixing zone 37, and the rainwater and sewage overflowing from the baffle mixing zone 37 enters the primary mixing and coagulation zone 321. The flow direction within the baffle mixing zone 37 is from bottom to top, which can play a certain role in settling sand.

[0107] Multiple stirring blades are arranged from top to bottom within the secondary stirred flocculation zone 322, with the stirring range of each blade gradually increasing from top to bottom. In the vertical direction, the differential stirring of multiple stirring blades of different sizes enables flocculation to proceed step by step from top to bottom. Specifically, the stirring intensity of the stirring blades located at the bottom is high, resulting in more collisions of floc particles. At the same time, it can also flush out the solid particles at the bottom to prevent the bottom magnetic powder from settling and caking due to gravity. The stirring intensity of the stirring blades located at the top is relatively low to prevent the flocs from breaking due to the same stirring intensity as the bottom, thereby ensuring the stability of the effluent from the secondary stirred flocculation zone 322.

[0108] The magnetic separation mechanism is used to separate magnetic flocs from rainwater and sewage purified by the coagulation mechanism; the magnetic separation mechanism includes a flow channel 341, a disk 342, a scraper bar 343, and a screw conveyor 344.

[0109] The flow channel 341 is connected to the upper part of the secondary stirring flocculation zone 322 via a pipe.

[0110] The disk 342 is rotatably disposed at the flow channel 341 for adsorbing magnetic flocs containing magnetic powder. The disk 342 has a multi-layered hollow structure and adopts an external inlet and internal outlet method. Specifically, the disk 342 has an outlet pipe 3421 arranged along its axis. Figure 3 In the indicated state, the outlet pipe 3421 does not radially penetrate the disk 342. Rainwater and sewage in the flow channel 341 pass through the layers of the disk 342 from the outside in, undergoing filtration, before being discharged from the outlet pipe 3421. Compared to the traditional solid disk 342, the multi-layered hollow structure of the disk 342 saves materials, reduces weight, and lowers investment and operating costs. Furthermore, because the traditional method uses water inlet on one side and outlet on the other, the magnetic flocs adsorbed on the outermost layer must separate from the rainwater and sewage under low rotation speed and high magnetic field force; otherwise, foaming and sludge problems easily occur. The multi-layered hollow structure of the disk 342, using an outside-in, inside-out method, not only solves the foaming and sludge problem but also improves the utilization rate of the disk 342, effectively increasing the water flow rate and the amount of water processed per unit disk 342.

[0111] The scraper strip 343 is positioned near the upper outer layer of the disk 342 and is used to work in conjunction with the rotating disk 342 to scrape off magnetic clumps. The scraper strip 343 is made of wear-resistant polymer materials such as polyurethane.

[0112] The inlet of the screw conveyor 344 is located close to the scraper bar 343, which is located between the inlet of the screw conveyor 344 and the disk 342. The screw conveyor 344 is used to transport the magnetic flocs scraped off the disk 342 by the scraper bar 343.

[0113] The magnetic recovery mechanism includes a high-speed deflocculator 361, a magnetic drum 362, a magnetic powder mixing box 363, and a magnetic powder dosing pump 364.

[0114] The inlet of the high-speed deflocculator 361 is connected to the outlet of the screw conveyor 344. A high-speed dispersing wheel is set in the center of the high-speed deflocculator 361. The high-speed dispersing wheel is used to shear the magnetic flocs by rapid rotation, so as to separate the magnetic powder and sludge in the magnetic flocs.

[0115] The magnetic drum 362 is used to adsorb the magnetic powder separated by the high-speed deflocculator 361. The magnetic powder adsorbed on the surface of the magnetic drum 362 is scraped off into the magnetic powder mixing box 363 by the scraper 365.

[0116] The magnetic powder mixing box 363 has a stirring function and is used to collect and stir the magnetic powder recovered by the magnetic drum 362.

[0117] The magnetic powder dosing pump 364 is installed inside the magnetic powder mixing tank 363 and is used to add the recovered magnetic powder to the primary mixing and coagulation zone 321. The magnetic powder dosing pump 364 is a wear-resistant pump.

[0118] The rapid purification device 3 also includes an online water quality monitor 39 and a rapid purification control cabinet 38; the online water quality monitor 39 is used to monitor the water quality at the outlet of the fine filtration and separation device 23 (real-time monitoring of SS or turbidity), and transmits the online monitoring data to the rapid purification control cabinet 38. The rapid purification control cabinet 38 generates corresponding instructions based on the data and sends the instructions to the mixing and dosing mechanism, coagulation mechanism, magnetic separation mechanism and magnetic recovery mechanism for execution.

[0119] The rapid purification control cabinet 38 also has a one-button start / stop function for controlling the mixing and dosing mechanism, coagulation mechanism, magnetic separation mechanism and magnetic recovery mechanism. In this way, the rapid purification device 3 can be started and stopped with one button, making it easy to operate.

[0120] Based on the above, the rapid purification device 3 has at least the following beneficial effects:

[0121] I. In view of the characteristics of large instantaneous flow and rapid purification of urban rainwater and sewage, this embodiment adopts the method of stirring coagulation (enhanced by guide tube 3212), stirring flocculation (differential stirring) combined with magnetic disk separation (magnetic disk 342 has a multi-layer hollow structure) to achieve rapid purification of urban rainwater and sewage, shorten the hydraulic residence time of rapid purification device 3. Compared with traditional coagulation and magnetic separation technology, the rapid purification time is shortened by 5-10 minutes and the treatment capacity is increased by 30%.

[0122] Second, the disk 342 has a multi-layered hollow structure and adopts an external inlet and internal outlet method, which not only solves the problem of sludge buildup, but also improves the utilization rate of the disk 342, effectively increasing the water flow rate of the disk 342 and the water processing capacity per unit disk 342.

[0123] Biological treatment device 4 is used to remove ammonia nitrogen, COD and total nitrogen from rainwater and sewage; biological treatment device 4 includes intermediate water tank 41, lift pump 42, nitrifying biological filter 43, autotrophic denitrifying filter 44 and aeration mechanism.

[0124] The inlet of the intermediate water tank 41 is connected to the outlet pipe 3421 of the disk 342.

[0125] The booster pump 42 is used to connect the outlet of the intermediate water tank 41 and the nitrifying biological filter 43.

[0126] The nitrifying biological filter 43 is used to remove ammonia nitrogen and COD; the nitrifying biological filter 43 includes a water distribution tank 431, nitrifying filter media 432 and a first support layer 433 arranged from top to bottom.

[0127] The inlet of the water distribution tank 431 is connected to the booster pump 42; the nitrifying biological filter 43 also includes an outlet tank 434 for draining water from the nitrifying biological filter, and the outlet of the outlet tank 434 is connected to the autotrophic denitrifying filter 44.

[0128] Nitrifying filter media 432 includes one or more of the following: crushed stone, volcanic rock, pebbles, cinders, and coke.

[0129] The first support layer 433 includes a first filter brick (not marked in the figure), which is used to support the nitrification filter media 432, and gas and liquid can pass through the first filter brick.

[0130] The self-atrophic denitrification filter 44 is used for denitrification to remove total nitrogen. The self-atrophic denitrification filter 44 includes a water distribution component 441, a denitrification filter media 442, a second support layer 443, and a denitrification drainage pipe 444 arranged sequentially from top to bottom.

[0131] The inlet of the water distribution component 441 is connected to the outlet of the water outlet tank 434. The outlet of the water distribution component 441 has multiple water distribution ports, which are used to distribute the incoming water.

[0132] Denitrification filter media 442 includes one or more of magnetite, sulfur and pyrite, and has a good denitrification effect.

[0133] The second support layer 443 includes a second filter brick (not marked in the figure), which supports the denitrification filter media 442, and allows gas and liquid to pass through the second filter brick.

[0134] A drain valve (not shown in the figure) is installed on the denitrification drain pipe 444, and the denitrification drain pipe 444 is connected to the sterilization and disinfection device.

[0135] Water from the outlet pipe 3421 of disk 342 enters the nitrification biological filter 43 to remove ammonia nitrogen and COD, and then enters the autotrophic denitrification filter 44 from the outlet of the outlet tank 434 to remove total nitrogen, and is then discharged from the denitrification drain pipe 444.

[0136] Both the aforementioned nitrifying biological filter 43 and the autotrophic denitrifying filter 44 are assembled using modular steel structures.

[0137] The aeration mechanism includes a perforated aeration pipe 451 and an intelligent variable frequency fan 452; an aeration valve (not marked in the figure) is provided on the perforated aeration pipe 451, the perforated aeration pipe 451 is located in the first support layer 433 and is connected to the intelligent variable frequency fan 452.

[0138] The biological treatment device 4 also includes a backwashing mechanism, which includes a first backwash water pipe 461, a second backwash water pipe 462, a backwash water pump 463, a first backwash air pipe 464, and a second backwash air pipe 465.

[0139] The outlet of the first backwash water pipe 461 is located below the first support layer 433, and the first backwash water pipe 461 is equipped with a first backwash water valve (not marked in the figure).

[0140] The outlet of the second backwash water pipe 462 is located below the second support layer 443, and a second backwash water valve (not marked in the figure) is installed on the second backwash water pipe 462.

[0141] The inlet of the backwash water pump 463 can be connected to the outlet pipe 3421 of the intermediate water tank 41 or the disk 342. In this embodiment, the inlet of the backwash water pump 463 is connected to the intermediate water tank 41, and the outlet of the backwash water pump 463 is connected to the first backwash water pipe 461 and the second backwash water pipe 462 respectively.

[0142] The outlet of the first backwash pipe 464 is located below the first support layer 433, and the first backwash pipe 464 is equipped with a first backwash valve (not marked in the figure).

[0143] The outlet of the second backwash pipe 465 is located below the second support layer 443, and a second backwash valve (not marked in the figure) is provided on the second backwash pipe 465.

[0144] The outlet of the intelligent variable frequency fan 452 is connected to the outlet of the first backwash pipe 464 and the outlet of the second backwash pipe 465, respectively.

[0145] The working principle of the first backwash water pipe 461, the second backwash water pipe 462, and the backwash water pump 463 is as follows: the backwash water pump 463 introduces water from the outlet pipe 3421 of the disk 342 into the nitrification biological filter 43 for backwashing through the first backwash water pipe 461, and into the autotrophic denitrification filter 44 through the second backwash air pipe 465 for backwashing. Part of the backwash water from the nitrification biological filter 43 is returned to the interception tank 13 of the precision interception and storage device 1, and the other part overflows into the autotrophic denitrification filter 44. The backwash water from the autotrophic denitrification filter 44 is returned to the interception tank 13 of the precision interception and storage device 1.

[0146] In addition, in this embodiment, a nitrogen removal overflow pipe (not shown in the figure) can be connected to the upper part of the autotrophic denitrification filter 44. The outlet of the nitrogen removal overflow pipe is connected to the intermediate water tank 41. The water washing and nitrogen removal of the autotrophic denitrification filter 44 share a set of devices. That is, the backwash water pump 463 and the second backwash water pipe 462 also have the nitrogen removal function in the autotrophic denitrification filter 44. The nitrogen removal water comes from the intermediate water tank 41. After nitrogen removal, the excess water overflows into the intermediate water tank 41 for further treatment. (The autotrophic denitrification filter 44 will generate nitrogen gas during normal operation. The nitrogen gas bubbles are intercepted by solid suspended matter and denitrification biofilm. During the denitrification process, the point-like nitrogen gas bubbles will accumulate on the surface of the medium. It is necessary to use external force to disturb them and destabilize them before discharging them out of the autotrophic denitrification filter 44 to restore the head.)

[0147] The biological treatment device 4 also includes an intelligent control cabinet (not shown in the figure) for timed start and stop of the booster pump 42, intelligent variable frequency fan 452, backwash water pump 463, drain valve, aeration valve, first backwash water valve, second backwash water valve, first backwash air valve and second backwash air valve, specifically:

[0148] When the biological treatment device 4 is operating normally, the intelligent control cabinet turns on the lift pump 42, the intelligent variable frequency fan 452, the aeration valve and the drain valve, and turns off the backwash pump 463, the first backwash water valve, the second backwash water valve, the first backwash air valve and the second backwash air valve.

[0149] During the backwashing of the nitrifying biological filter 43, the intelligent control cabinet shuts down the lift pump 42, aeration valve, second backwash water valve, second backwash air valve and drain valve, and opens the backwash water pump 463, first backwash water valve and first backwash air valve. The intelligent variable frequency blower 452 keeps running and increases the air supply by frequency conversion, thereby performing air and water backwashing on the nitrifying biological filter 43.

[0150] When backwashing the self-atrophic denitrification filter 44, the intelligent control cabinet shuts down the lift pump 42, aeration valve, first backwash water valve, first backwash air valve and drain valve, and opens the backwash water pump 463, second backwash water valve and second backwash air valve. The intelligent variable frequency fan 452 keeps running and increases the air supply by changing the frequency, thereby performing air and water backwashing on the self-atrophic denitrification filter 44.

[0151] During nitrogen removal in the autotrophic denitrification filter 44, the intelligent control cabinet closes the first backwash water valve, the first backwash air valve, and the drain valve, allowing the lift pump 42, the intelligent variable frequency fan 452, and the aeration valve to start normally, and opening the backwash water pump 463 and the second backwash water valve, thereby removing nitrogen from the autotrophic denitrification filter 44. After nitrogen removal, excess water overflows through the nitrogen removal overflow pipe into the intermediate water tank 41 for further treatment.

[0152] In summary, the biological treatment device 4 has at least the following beneficial effects:

[0153] I. Compared with traditional concrete structures, the nitrifying biological filter 43 and the autotrophic denitrifying filter 44 provided in this embodiment are both assembled from steel structures in a modular fashion, which facilitates assembly, transportation and on-site construction, and helps to shorten the construction period.

[0154] Second, traditional support layers use materials such as large-particle sand, pebbles, ceramsite, and slag, which are prone to biofilm growth and easy detachment, resulting in easy clogging of traditional support layers. The first support layer 433 uses the first filter brick, and the second support layer 443 uses the second filter brick. Both can be made of smooth materials such as HDPE plastic and ceramic composite materials, which can effectively prevent biofilm growth and detachment. Furthermore, because the first and second filter bricks are made of smooth materials, they are not easily clogged and are easy to backwash.

[0155] Third, the first support layer 433 uses the first filter brick, and the second support layer 443 uses the second filter brick. The backwash water and backwash air during backwashing can be evenly distributed when passing through the first filter brick and the second filter brick.

[0156] IV. In this embodiment, the two types of filter beds share the backwash water pump 463 and the intelligent variable frequency blower 452, and the air washing and aeration share a set of devices (the intelligent variable frequency blower 452 can automatically switch operating modes), which can reduce the number of supporting equipment.

[0157] Fifth, during nitrogen removal, the self-atrophic denitrification filter 44 can overflow excess water into the intermediate water tank 41 through the nitrogen removal overflow pipe for further treatment; in addition, in this embodiment, the water washing and nitrogen removal of the self-atrophic denitrification filter 44 can share a set of devices (backwash water pump 463 and corresponding valves automatically switch), which can further reduce the number of supporting equipment.

[0158] The sterilization and disinfection device sterilizes and disinfects rainwater and sewage; the device includes an ultraviolet sterilizer 51, which is connected to a denitrification drainage pipe 444. The sterilization and disinfection device discharges wastewater to a receiving water body or for resource utilization.

[0159] The aforementioned urban stormwater and sewage precision interception and rapid purification system can effectively control overflow pollution and initial rainwater pollution, while also taking into account the treatment and operation needs of both sunny and rainy days. This effectively reduces the impact of rainfall pollution on the urban water environment and alleviates the problems of water quality deterioration and blackening and odor after rain.

[0160] Secondly, please refer to Figures 1-5 This embodiment provides a method for precise interception, storage, and rapid purification of urban stormwater and sewage, which utilizes the aforementioned system for precise interception, storage, and rapid purification of urban stormwater and sewage. The method includes the following steps:

[0161] Step S1: Rainwater and sewage are precisely intercepted through the interception pool 13 of the precision interception and storage device 1, and the intercepted rainwater and sewage are precisely stored through the storage pool 14 of the precision interception and storage device 1.

[0162] Step S2: Remove sand from the regulated rainwater and sewage through the sand-water separator 22 of the sand and slag co-removal device 2;

[0163] Among them, the mud and sand produced by the sedimentation of the sand-water separator 22 are transported off-site for treatment, and the supernatant is returned to the storage tank 14;

[0164] Step S3: Remove slag from the rainwater and sewage after sand removal using the perforated plate grid equipment of the sand and slag co-removal device 2;

[0165] Among them, the screenings intercepted by the perforated plate grid equipment are pressed by the screw press 24 and then transported for processing.

[0166] Step S4: Add the agent to the rainwater and sewage after sludge removal in step S4 and perform non-powered mixing in the baffle mixing zone 37 of the rapid purification device 3;

[0167] The agents include coagulants;

[0168] Step S5: In the primary mixing and coagulation zone 321 of the rapid purification device 3, the rainwater and sewage after non-powered mixing are subjected to primary mechanical mixing.

[0169] Step S6: In the secondary stirring and flocculation zone 322 of the rapid purification device 3, the rainwater and sewage after primary mechanical stirring are subjected to secondary mechanical stirring.

[0170] Step S7: The rainwater and sewage after two-stage mechanical stirring are magnetically separated by the magnetic separation mechanism of the rapid purification device 3; the magnetic flocs obtained after magnetic separation are magnetically recovered.

[0171] Step S8: After magnetic separation, the rainwater and sewage first pass through the nitrification biological filter 43 and the autotrophic denitrification filter 44 of the biological treatment device 4 in sequence, and then are sterilized and disinfected before being discharged into the receiving water body or ecological replenishment water.

[0172] The nitrifying biological filter 43 and the autotrophic denitrifying filter 44 are backwashed regularly, and the backwash water is returned to the intercepting tank 13.

[0173] Finally, it should be noted that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations. Without conflict, the embodiments and features described in the embodiments of this application can be arbitrarily combined with each other. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A precise interception, storage, and rapid purification system for urban rainwater and sewage, characterized in that, include: Precision interception and storage devices are used to intercept and regulate rainwater and sewage. A sand and slag removal device is used to remove sand and slag from rainwater and sewage first. The rapid purification device uses a combination of stirring coagulation, stirring flocculation and disk separation to remove suspended solids and total phosphorus from rainwater and sewage, thus achieving rapid purification of rainwater and sewage. Biological treatment units are used to remove ammonia nitrogen, COD, and total nitrogen from rainwater and sewage. Sterilization and disinfection device, used to sterilize and disinfect rainwater and sewage; The precise storage interception device includes: A rainwater pipe connected to a first hydraulic flow control valve is used to transport rainwater to an interception tank; The stormwater and sewage pipe connected to the intercepting pool is equipped with a second hydraulic flow regulating valve; the stormwater and sewage pipe includes a sewage pipe and a combined pipe, the sewage pipe is adapted to the stormwater and sewage separate drainage system, and the combined pipe is adapted to the stormwater and sewage combined drainage system. The interception tank is equipped with a first submersible sewage pump and an overflow pipe, and a constant flow gate valve is connected to the overflow pipe; The regulating reservoir is connected to the intercepting reservoir via an openable and closable valve structure; At the beginning of the rainfall, open the first hydraulic flow control valve and the second hydraulic flow control valve, and close the gate valve and the first submersible sewage pump; in the middle and later stages of the rainfall, open the first hydraulic flow control valve and the second hydraulic flow control valve, close the valve structure leading to the storage tank, and open the first submersible sewage pump; at the end of the rainfall, open the first hydraulic flow control valve, the second hydraulic flow control valve, and the gate valve, and close the first submersible sewage pump and the valve structure. The biological treatment device includes: The intermediate water tank is connected to the inlet of the distribution tank via a booster pump; The nitrifying biological filter includes a water distribution tank, nitrifying filter media, and a first support layer arranged sequentially from top to bottom; the inlet of the water distribution tank is connected to the rapid purification device; and it also includes an outlet tank for draining water from the nitrifying biological filter. The self-atrophic denitrification filter includes, from top to bottom, a water distribution component, a denitrification filter media, a second support layer, and a denitrification drainage pipe; the inlet of the water distribution component is connected to the outlet of the effluent tank. The first support layer includes a first filter brick with a smooth material; the upper part of the autotrophic denitrification filter is connected to a nitrogen removal overflow pipe, and the outlet of the nitrogen removal overflow pipe is connected to the intermediate water tank.

2. The urban stormwater and sewage precision interception, storage, and rapid purification system according to claim 1, characterized in that, The storage tank adopts a tiered compartmentalized structure, with rainwater and sewage flowing sequentially through each compartment of the storage tank.

3. The urban stormwater and sewage precision interception, storage, and rapid purification system according to claim 1, characterized in that, The rapid purification device includes: The coagulation mechanism includes a primary mixing coagulation zone and a secondary mixing flocculation zone connected in sequence. The primary mixing coagulation zone achieves efficient coagulation of rainwater and sewage treated by the sand and slag co-removal device through mixing coagulation. The secondary mixing flocculation zone achieves efficient flocculation of rainwater and sewage through mixing flocculation. A magnetic separation mechanism is used to separate magnetic flocs from rainwater and sewage purified by the coagulation mechanism.

4. The urban stormwater and sewage precision interception, storage, and rapid purification system according to claim 3, characterized in that, The secondary stirring flocculation zone is provided with multiple stirring blades from top to bottom, and the stirring range of each stirring blade gradually increases from top to bottom.

5. The urban stormwater and sewage precision interception, storage, and rapid purification system according to claim 3, characterized in that, The primary mixing and coagulation zone is equipped with an agitator and a guide tube; the agitator has multiple blades arranged along its axial direction and is located inside the guide tube; both the upper and lower ends of the guide tube are open, and the upper diameter of the guide tube is smaller than its lower diameter.

6. The urban stormwater and sewage precision interception, storage, and rapid purification system according to claim 3, characterized in that, The magnetic separation mechanism includes: The flow channel is connected to the secondary stirring flocculation zone; A disk, rotatably disposed in the flow channel, is used to adsorb magnetic flocs containing magnetic powder; A scraper strip, located near the outer layer of the disk, is used to cooperate with the rotating disk to scrape off magnetic clumps; A screw conveyor for conveying magnetic flocs scraped off the disk by the scraper bars; The disk has a multi-layered hollow structure, and a water outlet pipe is provided along its axis. Rainwater and sewage in the flow channel are filtered through each layer of the disk from the outside to the inside before being discharged from the water outlet pipe.

7. The urban stormwater and sewage precision interception, storage, and rapid purification system according to any one of claims 3 to 6, characterized in that, The coagulation mechanism also includes a baffle mixing zone, which is connected to the primary stirring coagulation zone in sequence, and multiple baffles are staggered in the baffle mixing zone.

8. The urban stormwater and sewage precision interception, storage, and rapid purification system according to claim 1, characterized in that, The biological treatment device also includes: A perforated aeration pipe is installed inside the first support layer and connected to an intelligent variable frequency fan; The second backwash water pipe has its outlet located below the second support layer; the second support layer includes a second filter brick made of smooth material. A backwash water pump is used to connect the rapid purification device and the second backwash water pipe; The second backwash pipe is located below the second support layer and is connected to the intelligent variable frequency fan.

9. A method for precise interception, storage, and rapid purification of urban stormwater and sewage, employing the precise interception, storage, and rapid purification system for urban stormwater and sewage as described in any one of claims 1 to 8, characterized in that, Includes the following steps: Step S1: Precisely intercept and regulate rainwater and sewage; Step S2: Remove sand from the intercepted rainwater and sewage; Step S3: Remove slag from the rainwater and sewage after sand removal; Step S4: Add the agent to the rainwater and sewage after sludge removal and perform non-powered mixing; Step S5: Perform primary mechanical mixing on the rainwater and sewage after non-powered mixing; Step S6: Perform secondary mechanical mixing on the rainwater and sewage after primary mechanical mixing; Step S7: Perform magnetic separation on the rainwater and sewage after two-stage mechanical stirring; perform magnetic recovery on the magnetic flocs obtained after magnetic separation; Step S8: After magnetic separation, the rainwater and sewage are treated to remove ammonia nitrogen and COD, then the total nitrogen is removed, followed by sterilization and disinfection, and finally discharged into the receiving water body or ecological replenishment water.

Images