A magnetic coagulation wastewater treatment system

Abstract

A magnetic coagulation wastewater treatment system relates to the field of wastewater treatment technology. A mixing tank supplies water to a sedimentation tank. The mixing tank includes a magnetic powder mixing zone and a mixer. A sludge pump is connected to a discharge outlet at the bottom of the sedimentation tank for wastewater discharge. The ultrafiltration device includes a water storage tank and an external pressure hollow fiber membrane module. The inlet of the water storage tank is connected to a feed pump located at the top of the sedimentation tank via a pipeline. The external pressure hollow fiber membrane module is located inside the water storage tank, and its product water outlet is connected to a product water pipeline. A magnetic powder return pipe is additionally installed inside the water storage tank and connected to a pump located inside the magnetic powder mixing zone of the mixing tank via a pipeline. By adding an ultrafiltration device to filter the magnetic powder in the upper layer of clear water discharged from the sedimentation tank, and by backwashing, the magnetic powder can be returned to the magnetic powder mixing zone of the upstream mixing tank, which not only avoids waste of magnetic powder but also further improves water quality.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment technology, specifically a magnetic coagulation wastewater treatment system. Background Technology

[0002] Magnetic coagulation is an advanced water treatment technology that combines magnetic separation technology with coagulation and flocculation sedimentation technology. By adding magnetic powder to the ordinary coagulation and sedimentation process, the magnetic field is used to rapidly aggregate suspended solids and colloidal substances in the water and form larger flocs. This allows the magnetic powder to effectively combine with the flocs, accelerating the sedimentation process of the flocs. Due to its high efficiency, environmental protection, and energy saving, it has been widely used in the field of wastewater treatment.

[0003] However, conventional magnetic coagulation wastewater treatment systems discharge the supernatant water directly after sedimentation in the sedimentation tank. Although most of the magnetic powder settles along with the flocs, a small amount of magnetic powder will still remain suspended in the supernatant water and be discharged together due to excessive magnetic powder addition or disturbance caused by the discharge of sedimented sludge. This not only wastes the magnetic powder but also reduces the quality of the discharged water. Summary of the Invention

[0004] To address the shortcomings of the prior art, this utility model provides a magnetic coagulation wastewater treatment system. It filters the magnetic powder in the upper layer of clear water discharged from the sedimentation tank by adding an ultrafiltration device, and can return the magnetic powder to the magnetic powder mixing zone of the front-end mixing tank through backwashing. This not only avoids the waste of magnetic powder, but also further improves the water quality.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a magnetic coagulation wastewater treatment system, comprising a mixing tank, a sedimentation tank, a sludge pump, and an ultrafiltration device. The mixing tank supplies water to the sedimentation tank. The mixing tank includes a magnetic powder mixing zone and is equipped with a stirrer. A sludge outlet is provided at the bottom of the sedimentation tank and connected to the sludge pump for sludge discharge. The ultrafiltration device includes a water storage tank and an external pressure hollow fiber membrane module. The inlet of the water storage tank is connected to a water supply pump installed at the top of the sedimentation tank via a pipeline. The external pressure hollow fiber membrane module is installed inside the water storage tank. The product water outlet of the external pressure hollow fiber membrane module extends out of the water storage tank and is connected to a product water pipeline. A magnetic powder return pipe is additionally installed inside the water storage tank. The magnetic powder return pipe extends out of the water storage tank and is connected to a water pump installed inside the magnetic powder mixing zone of the mixing tank via a pipeline.

[0006] Furthermore, the mixing tank also includes a coagulant dosing area and a flocculant dosing area connected at the beginning and end of the magnetic powder mixing zone. Both the coagulant dosing area and the flocculant dosing area are equipped with a mixer. The coagulant dosing area is on the inlet side, and the flocculant dosing area is on the outlet side and connected to the sedimentation tank.

[0007] Furthermore, a magnetic powder recovery mechanism is installed between the magnetic powder mixing zone of the mixing tank and the sludge pump. The magnetic powder recovery mechanism includes a high-shear mill and a magnetic separator. The feed end of the high-shear mill is connected to the sludge pump through a pipeline, and the discharge end of the high-shear mill is connected to the magnetic separator through a pipeline. The magnetic separator sends the recovered magnetic powder back to the magnetic powder mixing zone of the mixing tank.

[0008] Furthermore, the high-speed shearing machine includes a cylindrical outer shell, a rotating shaft, and a drive motor. The outer wall of the cylindrical outer shell is connected to a feed inlet and a discharge outlet. The feed inlet is located below the cylindrical outer shell, and the discharge outlet is located above the cylindrical outer shell. The rotating shaft is coaxially rotatably installed inside the cylindrical outer shell, and multiple impellers are uniformly fixed along its side wall along the axial direction. The drive motor is fixedly installed on the top of the cylindrical outer shell and connected to the drive rotating shaft. Multiple conical guide shields are uniformly arranged along the axial direction on the inner wall of the cylindrical outer shell. Each conical guide shield corresponds to one of the impellers, and two or more shearing blades are uniformly fixed on the edge of each impeller. The shearing blades are arranged along the generatrix direction of the conical guide shield.

[0009] Furthermore, the angle between the generatrix of the conical shroud and the inner wall of the cylindrical outer shell is 30°~45°.

[0010] Furthermore, a sludge return pipeline is also installed between the magnetic powder mixing zone of the mixing tank and the sludge pump.

[0011] Furthermore, the sedimentation tank is a rectangular trough structure with V-shaped trough bottoms on both sides that slope towards the center of the sewage outlet. Two opening and closing chute plates are hinged to the inner walls of both sides of the sedimentation tank near the bottom. Hydraulic telescopic rods are respectively hinged between the center of the bottom of the two opening and closing chute plates and the corresponding position of the V-shaped trough bottom of the sedimentation tank. When the two hydraulic telescopic rods reach their maximum extension, the free ends of the two opening and closing chute plates are fitted together.

[0012] Furthermore, a geared motor is fixedly installed above the sewage outlet of the sedimentation tank. The geared motor is connected to a drive spiral blade shaft, which extends coaxially into the sewage outlet.

[0013] Furthermore, both of the opening and closing slides have a mirror finish.

[0014] Furthermore, control valves are respectively installed on the pipeline corresponding to the water inlet of the water storage tank, the pipeline corresponding to the magnetic powder return pipe, and the water production pipeline.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows: By adding an ultrafiltration device at the rear end of the sedimentation tank, the magnetic powder in the upper layer of clear water discharged from the sedimentation tank can be filtered. Moreover, the magnetic powder can be returned to the magnetic powder mixing zone of the front mixing tank through backwashing, which avoids waste of magnetic powder and effectively improves water quality. In addition, two opening and closing chute plates controlled by hydraulic telescopic rods are set at the bottom of the sedimentation tank. During sedimentation, the separation of the two opening and closing chute plates helps the flocs to gather towards the discharge port. During discharge, the closure of the two opening and closing chute plates helps to prevent the disturbance caused by discharge from causing the flocs to float to the top. Furthermore, the high shear machine of the magnetic powder recovery mechanism has been optimized and improved. Through the design of the conical guide hood and shearing blade, not only can the turbulence state of the internal sludge be increased, making the flocs break more thoroughly, but the guiding effect can also reduce the problem of clogging, which is beneficial to the magnetic powder recovery of the subsequent magnetic separator. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the magnetic coagulation wastewater treatment system of this utility model;

[0017] Figure 2 This is a schematic diagram of the ultrafiltration device in this utility model;

[0018] Figure 3 This is a structural schematic diagram of the high-speed shearing machine of this utility model;

[0019] Figure 4 This is a schematic diagram of the sedimentation tank in this utility model.

[0020] In the diagram: 1. Mixing tank; 2. Sedimentation tank; 3. Sludge pump; 4. High shear machine; 5. Magnetic separator; 6. Ultrafiltration unit; 2-1. Opening and closing chute; 2-2. Hydraulic telescopic rod; 2-3. Gear motor; 2-4. Spiral blade shaft; 4-1. Cylindrical outer shell; 4-2. Rotating shaft; 4-3. Drive motor; 4-4. Impeller; 4-5. Shearing blade; 4-11. Feed inlet; 4-12. Discharge outlet; 4-13. Conical guide hood; 6-1. Water storage tank; 6-2. External pressure hollow fiber membrane module. Detailed Implementation

[0021] The technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of the utility model, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the protection scope of this utility model.

[0022] like Figures 1-4As shown, a magnetic coagulation wastewater treatment system includes a mixing tank 1, a sedimentation tank 2, a sludge pump 3, a magnetic powder recovery mechanism, and an ultrafiltration device 6.

[0023] Combination Figure 1 As shown, the mixing tank 1 supplies water to the sedimentation tank 2. It includes a coagulant dosing zone, a magnetic powder mixing zone, and a flocculant dosing zone, all connected sequentially. Each zone is equipped with a mixer. The coagulant dosing zone, on the inlet side, is used to add coagulants such as PAC, with a mixer speed of 250 r / min. The magnetic powder mixing zone is used to add magnetic powder, as well as magnetic powder recovered by the magnetic separator 5 and ultrafiltration device 6. Rapid mixing ensures the magnetic powder is quickly mixed with the inlet water from the coagulation process, with a mixer speed of 250 r / min. The flocculant dosing zone, on the outlet side, connects to the sedimentation tank 2 and is used for adding and mixing flocculants. Slow mixing promotes the settling of magnetic powder and insoluble substances in the water, with a mixer speed of 70-80 r / min. A sludge discharge port is located at the bottom of the sedimentation tank 2 and connected to the sludge pump 3 for sludge discharge. A magnetic powder recovery mechanism and an additional sludge return pipeline are installed between the magnetic powder mixing zone of the mixing tank 1 and the sludge pump 3. The magnetic powder recovery mechanism is used to recover magnetic powder from sludge, including a high-shear mill 4 and a magnetic separator 5. The feed end of the high-shear mill 4 is connected to the sludge pump 3 via a pipeline, and the discharge end of the high-shear mill 4 is connected to the magnetic separator 5 via a pipeline. The magnetic separator 5 sends the recovered magnetic powder back to the magnetic powder mixing zone of the mixing tank 1. The magnetic separator 5 is preferably a rotary drum type magnetic separator. The sludge return pipeline further ensures the balance of sludge in the sedimentation tank 2. The upper layer of clear water in the sedimentation tank 2 is connected to an ultrafiltration device 6 to filter the magnetic powder therein. The concentrate from the ultrafiltration device 6 is returned to the magnetic powder mixing zone of the front-end mixing tank 1. In addition, the magnetic powder is also returned to the magnetic powder mixing zone of the front-end mixing tank 1 by backwashing.

[0024] Combination Figure 2As shown, the ultrafiltration device 6 includes a water storage tank 6-1 and an external pressure hollow fiber membrane module 6-2. The inlet of the water storage tank 6-1 is connected to a water pump installed at the top of the sedimentation tank 2 via a pipeline. The external pressure hollow fiber membrane module 6-2 is installed inside the water storage tank 6-1. The product water outlet of the external pressure hollow fiber membrane module 6-2 extends out of the water storage tank 6-1 and is connected to a product water pipeline. The product water efficiency is improved by using a vacuum pump at the end of the product water pipeline. A magnetic powder return pipe is additionally installed inside the water storage tank 6-1. The magnetic powder return pipe extends out of the water storage tank 6-1 and is connected to a water pump installed inside the magnetic powder mixing zone of the mixing tank 1 via a pipeline. Control valves are installed on the pipeline corresponding to the inlet of the water storage tank 6-1, the pipeline corresponding to the magnetic powder return pipe, and the product water pipeline, respectively. During the process of supplying the upper layer of clear water from sedimentation tank 2 to ultrafiltration device 6, only the control valve of the pipeline corresponding to the magnetic powder return pipe is closed. The upper layer of clear water from sedimentation tank 2 acts on the outer wall of the external pressure hollow fiber membrane module 6-2 through the feed water pump. The magnetic powder is blocked in the water storage tank 6-1, while the water enters the central cavity of the external pressure hollow fiber membrane module 6-2. The ultrafiltered water flows through the product water outlet of the external pressure hollow fiber membrane module 6-2 to the product water pipeline for water production. During the backwashing and recovery of magnetic powder, the water storage tank 6-1 is closed. The control valve of the pipeline corresponding to the inlet of the ultrafiltration device 6 pressurizes the end of the product water pipeline to make the product water of the ultrafiltration device 6 flow back under pressure, and backwash the external pressure hollow fiber membrane module 6-2. The backwash liquid passes through the membrane fibers in reverse to wash away the magnetic powder accumulated on the outer wall of the external pressure hollow fiber membrane module 6-2. Under the action of the water pump, the water in the water storage tank 6-1 flows back to the magnetic powder mixing zone of the mixing tank 1 through the magnetic powder return pipe and its corresponding pipeline, so as to realize the recovery of magnetic powder in the upper clear water.

[0025] Combination Figure 3As shown, the high-speed shearing machine 4 includes a cylindrical outer shell 4-1, a rotating shaft 4-2, and a drive motor 4-3. The outer wall of the cylindrical outer shell 4-1 is connected to a feed inlet 4-11 and a discharge outlet 4-12. The feed inlet 4-11 is located below the cylindrical outer shell 4-1, and the discharge outlet 4-12 is located above the cylindrical outer shell 4-1. The rotating shaft 4-2 is coaxially rotatably mounted inside the cylindrical outer shell 4-1, and multiple impellers 4-4 are evenly fixed along its sidewalls along the axial direction. The drive motor 4-3 is fixedly mounted on the top of the cylindrical outer shell 4-1 and connected to the rotating shaft 4-2. Multiple conical guide shields 4-13 are evenly arranged along the axial direction on the inner wall of the cylindrical outer shell 4-1. Each conical guide shield 4-13 corresponds to one impeller 4-4, and two or more shearing blades 4 are evenly fixed to the edge of each impeller 4-4. -5, the shearing blades 4-5 are arranged along the generatrix of the conical guide shroud 4-13. The angle between the generatrix of the conical guide shroud 4-13 and the inner wall of the cylindrical shell 4-1 is 30°~45°. The structure can be made by integral casting to ensure structural strength. This design optimizes and improves the high-speed shear machine 4. It mainly utilizes the inner cavity configuration of the special cylindrical shell 4-1 with the conical guide shroud 4-13, combined with the impeller 4-4 and the shearing blades 4-5 that cooperate with the conical guide shroud 4-13, to increase the turbulence of the sludge, so that the flocs are broken up more quickly and thoroughly, which is convenient for subsequent magnetic powder recycling. At the same time, the inclined structure of the conical guide shroud 4-13 increases the flow guidance state and helps to reduce clogging.

[0026] Combination Figure 4 As shown, the sedimentation tank 2 preferably adopts a rectangular trough structure with its bottom sides set as V-shaped trough bottoms inclined towards the central discharge outlet. Two opening and closing chute plates 2-1 are hinged to the inner walls of both sides of the sedimentation tank 2 near the bottom. Hydraulic telescopic rods 2-2 are respectively hinged between the center of the bottom of the two opening and closing chute plates 2-1 and the corresponding position of the V-shaped trough bottom of the sedimentation tank 2. When the two hydraulic telescopic rods 2-2 reach their maximum extension, the free ends of the two opening and closing chute plates 2-1 are fitted together. In this way, during the settling period, the contraction of the two hydraulic telescopic rods 2-2 can separate the two opening and closing chute plates 2-1, which helps the sludge to gather towards the discharge outlet. During the discharge period, the extension of the two hydraulic telescopic rods 2-2 to the maximum can close the two opening and closing chute plates 2-1, thereby separating the bottom sludge from the upper clear water and preventing the disturbance caused by the discharge from causing the flocs to float to the top. In addition, to facilitate the flow of sludge, it is advisable to mirror-finish the surfaces of both opening and closing chute 2-1. A reduction motor 2-3 can also be fixedly installed above the discharge port of the sedimentation tank 2. The reduction motor 2-3 is connected to drive the spiral blade shaft 2-4. The spiral blade shaft 2-4 extends coaxially into the discharge port to avoid clogging the discharge port during sludge discharge.

[0027] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of the equivalents of the claims are intended to be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0028] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A magnetic coagulation sewage treatment system, characterized in that: The system includes a mixing tank (1), a sedimentation tank (2), a sludge pump (3), and an ultrafiltration device (6). The mixing tank (1) supplies water to the sedimentation tank (2). The mixing tank (1) includes a magnetic powder mixing zone and is equipped with a mixer. The sedimentation tank (2) has a sludge outlet at the bottom and is connected to the sludge pump (3) for sludge discharge. The ultrafiltration device (6) includes a water storage tank (6-1) and an external pressure hollow fiber membrane module (6-2). The inlet of the water storage tank (6-1) is connected to... The external pressure hollow fiber membrane module (6-2) is installed inside the water storage tank (6-1) and the water outlet of the external pressure hollow fiber membrane module (6-2) extends out of the water storage tank (6-1) and is connected to the water production pipeline. A magnetic powder return pipe is additionally installed inside the water storage tank (6-1). The magnetic powder return pipe extends out of the water storage tank (6-1) and is connected to the water pump installed inside the magnetic powder mixing zone of the mixing tank (1) through the pipeline.

2. The magnetic coagulation sewage treatment system according to claim 1, characterized in that: The mixing tank (1) also includes a coagulant dosing area and a flocculant dosing area connected at the beginning and end of the magnetic powder mixing zone. Both the coagulant dosing area and the flocculant dosing area are equipped with a mixer. The coagulant dosing area is the inlet side, and the flocculant dosing area is the outlet side connected to the sedimentation tank (2).

3. The magnetic coagulation wastewater treatment system according to claim 1 or 2, characterized in that: A magnetic powder recovery mechanism is installed between the magnetic powder mixing zone of the mixing tank (1) and the sludge pump (3). The magnetic powder recovery mechanism includes a high shear machine (4) and a magnetic separator (5). The feed end of the high shear machine (4) is connected to the sludge pump (3) through a pipeline, and the discharge end of the high shear machine (4) is connected to the magnetic separator (5) through a pipeline. The magnetic separator (5) sends the recovered magnetic powder back to the magnetic powder mixing zone of the mixing tank (1).

4. The magnetic coagulation sewage treatment system according to claim 3, characterized in that: The high-speed shear machine (4) includes a cylindrical outer shell (4-1), a rotating shaft (4-2), and a drive motor (4-3). The outer wall of the cylindrical outer shell (4-1) is connected to a feed inlet (4-11) and a discharge outlet (4-12). The feed inlet (4-11) is located below the cylindrical outer shell (4-1), and the discharge outlet (4-12) is located above the cylindrical outer shell (4-1). The rotating shaft (4-2) is coaxially and rotatably installed inside the cylindrical outer shell (4-1), and multiple impellers are evenly fixed along its side wall along the axial direction. (4-4) The drive motor (4-3) is fixedly installed on the top of the cylindrical shell (4-1) and connected to the transmission rotating shaft (4-2). Multiple conical guide shields (4-13) are evenly arranged along the axial direction on the inner wall of the cylindrical shell (4-1). The conical guide shields (4-13) are arranged one-to-one with the impellers (4-4), and two or more shearing blades (4-5) are evenly fixed on the edge of each impeller (4-4). The shearing blades (4-5) are arranged along the generatrix direction of the conical guide shields (4-13).

5. The magnetic coagulation wastewater treatment system according to claim 4, wherein: The angle between the generatrix of the conical shroud (4-13) and the inner wall of the cylindrical shell (4-1) is 30°~45°.

6. The magnetic coagulation wastewater treatment system according to claim 3, wherein: A sludge return pipeline is also installed between the magnetic powder mixing zone of the mixing tank (1) and the sludge pump (3).

7. The magnetic coagulation wastewater treatment system according to claim 1, wherein: The sedimentation tank (2) is a rectangular trough structure with V-shaped trough bottoms on both sides that are inclined toward the center of the sewage outlet. Two opening and closing slides (2-1) are hinged to the inner walls on both sides of the sedimentation tank (2) near the bottom. Hydraulic telescopic rods (2-2) are respectively hinged between the center of the bottom of the two opening and closing slides (2-1) and the corresponding position of the V-shaped trough bottom of the sedimentation tank (2). When the two hydraulic telescopic rods (2-2) reach their maximum extension, the free ends of the two opening and closing slides (2-1) are fitted together.

8. The magnetic coagulation wastewater treatment system according to claim 7, wherein: A speed reduction motor (2-3) is fixedly installed above the sewage outlet of the sedimentation tank (2). The speed reduction motor (2-3) is connected to a drive spiral blade shaft (2-4). The spiral blade shaft (2-4) extends coaxially into the sewage outlet.

9. The magnetic coagulation wastewater treatment system according to claim 7, wherein: The surfaces of both opening and closing slides (2-1) are mirror-finished.

10. The magnetic coagulation wastewater treatment system according to claim 1, wherein: Control valves are respectively installed on the pipeline corresponding to the water inlet of the water storage tank (6-1), the pipeline corresponding to the magnetic powder return pipe, and the water production pipeline.

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