Air float outer pressure type membrane integrated water treatment system

Abstract

The application discloses a gas float outer pressure type membrane integrated water treatment system and belongs to the technical field of water treatment. The water treatment system comprises a gas float tank, a partition plate is arranged in the gas float tank, the gas float tank is divided into a dissolved gas releasing area and a filtering area, an air inlet is arranged at the bottom of the dissolved gas releasing area, a liquid inlet is arranged at the side of the dissolved gas releasing area, a filtering membrane group arranged with partitions is arranged in the filtering area, a first pipe body is connected to the upper portion of the filtering membrane group, the filtering membrane group has a hollow structure and is vertically arranged, and fine holes are uniformly distributed on the wall of the membrane filament. The system layout of the application has a small land occupation, the water treatment effect is strengthened through the gas float and membrane filtering modes, the water quality stability of effluent can be ensured, and the maintenance cost is low.

Description

Technical Field

[0001] This invention relates to the field of water treatment technology, specifically to an integrated air flotation and external pressure membrane water treatment system. Background Technology

[0002] In the field of water treatment technology, with the continuous improvement of drinking water hygiene standards and the increasing demand for the reuse of industrial wastewater and municipal sewage, water treatment systems require higher precision, operational efficiency, land area, and ease of maintenance. Currently, commonly used water treatment processes include a combination of air flotation (AF) and conventional processes. In the existing water supply sector, AF combined with conventional processes (such as coagulation, sedimentation, and filtration) using separate structures is a typical application. The advantages of this approach are abundant basic design data for each process, strong controllability, and high safety and reliability. However, its main disadvantages are that each process requires separate structures, resulting in a large land area, high initial investment costs, and a long construction period; the entire system has many devices, and the mechanical parts require regular inspection, leading to high maintenance costs. Another example is integrated AF and sand filtration technology, which is already relatively mature in the existing water supply sector. The advantages of this technology are short construction period, flexible installation, small land area, and the ability to perform AF and filtration simultaneously, achieving an effluent turbidity of less than 0.5 NTU. However, the main drawback of this technology is that it is difficult to control the effluent quality to a lower level and it has a weak ability to cope with sudden changes in water quality and quantity.

[0003] Meanwhile, in response to the aforementioned increased water treatment requirements, existing patented technologies have outlined upgraded processes for air flotation treatment. For example, WO2023102958A1 discloses an integrated air flotation filter device. This device includes at least one rapid mixing tank, at least one pair of water distribution tanks, at least one pair of flocculation tanks, at least one pair of flotation filter tanks, and at least one scum tank. This integrated device simultaneously implements air flotation and filtration processes, improving dissolved air release efficiency, extending backwashing cycles, reducing maintenance difficulty, lowering equipment operation and maintenance costs, and enhancing equipment operational stability while ensuring water treatment effectiveness. Another example is the existing patent technology, ATE1145282T1, which discloses a water treatment process and corresponding equipment combining flotation and gravity filtration. This invention can achieve water treatment that makes the water potable or desalinated. It is evident that existing water treatment technologies are continuously improving to meet water demand and quality requirements. However, current water treatment processes struggle to consistently meet standards when dealing with complex water qualities and are easily limited by site and cost constraints. Summary of the Invention

[0004] The purpose of this invention is to provide an integrated air flotation and external pressure membrane water treatment system that occupies a small area, enhances water treatment effect through air flotation and membrane filtration, ensures stable effluent quality, and has low maintenance costs.

[0005] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution: an integrated water treatment system using an external pressure membrane flotation system, comprising a flotation tank, which is divided into a dissolved air release zone and a filtration zone by a partition. The dissolved air release zone has an air inlet at its bottom and a liquid inlet on its side. The filtration zone contains compartmentalized filter membrane modules, with a first tube connected to the upper part of each module. The filter membrane modules have a hollow structure and consist of vertically arranged membrane fibers, with fine pores evenly distributed on the membrane fiber tube walls. A sludge discharge port is located at the bottom of the filtration zone for timely discharge of deposited sludge. The filter membrane modules use flat ceramic membranes, which are arranged in a module configuration. The membrane fibers form a flat ceramic membrane, which is then integrated into a single membrane module. The membrane fibers are external pressure membranes with a hollow structure, and a large number of fine pores with a diameter of 0.1 micrometers are evenly distributed on the membrane fiber tube walls. The membrane fibers constitute vertically arranged submerged perforated effluent pipes with an opening diameter of 0.1 micrometers.

[0006] This invention uses a partition inside the flotation tank to separate the dissolved air release zone and the filtration zone, achieving integrated dissolved air flotation and membrane filtration to reduce land occupation and simplify the water treatment system. The dissolved air release zone has an air inlet at the bottom and a liquid inlet on the side for media entry, enabling suspended solids to be separated by flotation. The filtration zone further features compartmentalized filter membrane modules, vertically arranged to form submerged perforated outlet pipes. The upper first pipe of the filter membrane module facilitates the transport of produced water. During the discharge of filtered water from the flotation tank, the water flows out through the pores in the membrane fiber tube wall. This process helps to generate a uniform upward flow velocity in the flotation tank, and the fluid movement direction is consistent with the solid-liquid separation direction of the flotation. This not only achieves the discharge of purified water but also improves the solid-liquid separation efficiency and, by enhancing fluid movement, helps to reduce the probability of adhesion to the inner wall of the flotation tank.

[0007] According to one embodiment of the present invention, the horizontal height of the baffle is lower than that of the dissolved air flotation tank, which is used to form a water level gradient. This allows the clear liquid after dissolved air flotation separation in the dissolved air release zone to naturally overflow into the filtration zone without the need for additional power supply. At the same time, it avoids the water in the dissolved air flotation tank from overflowing, ensuring that the dissolved air release zone has sufficient space to complete the floating and separation of suspended solids. Furthermore, the angle between the baffle and the filtration zone is smaller than the angle between the baffle and the dissolved air release zone. On the one hand, this extends the residence time of the liquid in the dissolved air release zone, ensuring that the bubbles and suspended solids fully contact and adhere, thereby improving the efficiency of dissolved air flotation for removing impurities. On the other hand, it guides the clarified liquid into the filtration zone at a stable flow rate, avoiding water flow impacting the filter membrane assembly and reducing the risk of unseparated impurities disturbing and contaminating the membrane fibers. It also helps to evenly distribute the liquid to the compartmented filter membrane assembly.

[0008] According to one embodiment of the present invention, a water collection tank is provided outside the flotation tank. The water collection tank is connected to the filter membrane assembly through a first pipe, which receives the filtered water from the filter membrane assembly and can supply water for backwashing when the filter membrane assembly needs backwashing. A suction pump is provided on the first pipe. Specifically, when the transmembrane pressure difference of the ceramic membrane reaches a certain value, rinsing is required. At this time, the scum generated by flotation is first scraped off, and the suction pump is used to pressurize and transport it from the water collection tank to the membrane fiber center tube. The water then enters the filtration zone through the tiny pores on the membrane fiber, achieving water washing of the membrane fiber pores and surface, making the membrane fiber clean again. If necessary, a blower is started to achieve air-water rinsing of the membrane fiber.

[0009] According to one embodiment of the present invention, an air compressor and a pressure dissolved air tank are provided outside the flotation tank. The air compressor is connected to the pressure dissolved air tank, which is connected to the air inlet at the bottom of the dissolved air release zone via a connecting pipe. The pressure dissolved air tank is connected to a water collection tank via a third pipe. The air compressor inputs compressed air into the pressure dissolved air tank and uses filtered water from the water collection tank transported by the third pipe. Sufficient mass transfer and dissolution of air and water are achieved within the pressure dissolved air tank, forming high-concentration dissolved air water. This dissolved air water is then transported to the air inlet at the bottom of the dissolved air release zone via the connecting pipe. After being depressurized by the release device, a large number of uniform microbubbles are generated, which can efficiently adhere to suspended solids in the water to form scum, improving the flotation separation efficiency. Simultaneously, using the clean water from the water collection tank as the dissolved air water source reduces the interference of impurities in the raw water on the dissolved air process and achieves water resource circulation within the system, reducing the filtration pressure on subsequent filter membrane modules.

[0010] According to one embodiment of the present invention, a mixing tank is provided outside the flotation tank. The mixing tank is connected to the liquid inlet on the side of the dissolved air release zone via a connecting pipe. A first agitator is provided on the mixing tank. The first agitator has a stirring blade and a driving component disposed in the mixing tank. The first agitator on the mixing tank can rotate under the drive of the driving component to fully mix the raw water and the coagulant, promoting the formation of structurally stable flocs of suspended solids in the water. This solves the problem of floc breakage or insufficient formation caused by uneven mixing in traditional methods. After the water is fully mixed by the first agitator enters the dissolved air release zone, it can efficiently combine with the microbubbles released from the dissolved air water input at the bottom air inlet, improving the flotation and separation efficiency of suspended solids and reducing the pollution of the filter membrane in the filtration zone by unseparated impurities.

[0011] According to one embodiment of the present invention, a separator is provided in the dissolved gas release zone. The separator is located on the air inlet at the bottom of the dissolved gas release zone, and its horizontal height is lower than that of the liquid inlet on the side of the dissolved gas release zone. The separator includes bent plates arranged at intervals in sequence. The bent plates are connected to each other by elastic members. The bent plates at the edge of the separator are connected to the flotation tank by fasteners. The bent plates include a first plate and a second plate, and there is an included angle between the first plate and the second plate. The first and second plates of the bending plate form an angle to guide the dissolved air and water released from the air inlet in different directions. Combined with the spaced arrangement, this solves the problem of concentrated release and easy aggregation of bubbles, achieving uniform distribution of microbubbles in the dissolved air release area. Furthermore, the bending plates are connected by elastic elements, which can produce slight deformation with the impact of water flow. This avoids water flow obstruction caused by rigid connection and can further disperse bubbles through elastic vibration. In addition, the horizontal height of the separator is lower than the side inlet of the dissolved air release area. This allows the water pretreated in the mixing tank to flow through the area above the separator after entering from the inlet, forming a cross-flow contact state with the dispersed microbubbles. That is, the raw water flows from top to bottom, and the bubbles float from bottom to top, prolonging the contact time between the two and ensuring that the bubbles fully adhere to the flocs and suspended solids in the raw water. This solves the problem of bubble breakage or insufficient contact caused by water directly impacting the bubbles at the air inlet.

[0012] According to one embodiment of the present invention, a mixing tank is provided outside the flotation tank. The mixing tank is connected to the liquid inlet on the side of the dissolved gas release zone through a connecting pipe. A second stirrer is provided on the mixing tank. The second stirrer includes a mounting base plate fixedly mounted on the mixing tank. A first rotating shaft and a second rotating shaft that can rotate are respectively provided on the mounting base plate. The axes of the first rotating shaft and the second rotating shaft are parallel to the liquid outlet direction of the mixing tank. A first stirring frame is provided on the first rotating shaft, and a second stirring frame is provided on the second rotating shaft.

[0013] The axes of the first and second rotating shafts are parallel to the liquid outlet direction of the mixing tank, so that the stirring direction of the first and second stirring frames is consistent with the water flow direction, solving the problem of water flow obstruction in traditional vertical stirring. Furthermore, when the first and second stirring frames rotate synchronously, they can cover a larger cross section of the mixing tank, avoiding stirring dead corners. They can also work with the frame structure to cut and disturb the water flow, allowing the coagulant to mix with the water quickly.

[0014] According to one embodiment of the present invention, a second gear is provided on the mounting base plate, and a first drive motor connected to the second gear is provided on one side of the mounting base plate. First gears are symmetrically provided on both sides of the second gear, one of the first gears being coaxially connected to a first rotating shaft, and the other first gear being coaxially connected to a second rotating shaft. The second gear on the mounting base plate rotates under the drive of the first drive motor. Through the symmetrical meshing of the first gears on both sides, the coaxial first rotating shaft and second rotating shaft are synchronously driven to rotate, ensuring that the rotation speeds of the first rotating shaft and the second rotating shaft are consistent, and avoiding the asynchronous stirring caused by traditional independent drives.

[0015] According to one embodiment of the present invention, the horizontal planes of the first stirring frame and the second stirring frame have an included angle, and the inner lining of the frame structure of the first stirring frame and the second stirring frame are provided with inclined plates arranged at intervals in sequence.

[0016] The ends of the first and second rotating shafts are rotatably connected to connecting plates. The first and second stirring frames are rectangular frame structures. The rectangular structure of the first and second stirring frames, with an angle between them on the horizontal plane, allows them to form a three-dimensional cross disturbance during stirring. Compared with a single-plane stirring method, this can better solve the problem of water stratification and avoid mixing dead zones. When the first and second stirring frames rotate synchronously with the first and second rotating shafts, the water flow will come into contact with the inclined plate multiple times. In this way, the inclined plate can cut the water flow. This not only achieves water propulsion, but also guides the water flow to form multiple small eddies through the inclination angle of the inclined plate itself, causing the coagulant particles to disperse from a locally aggregated state to a uniformly suspended state, thus solving the problem of uneven coagulant dispersion.

[0017] Furthermore, the connecting plates at the ends of the first and second rotating shafts further reinforce the first and second rotating shafts, preventing frame displacement due to vibration during rotation and improving overall operational stability.

[0018] The mounting base plate has an inlet opening, and the mixing tank has an inlet hole connected to the inlet opening and an inlet pipe with a valve on the inlet pipe.

[0019] According to one embodiment of the present invention, a blower is provided outside the flotation tank, and the blower is connected to the bottom of the filter module through a second pipe. During backwashing, the second pipe sends compressed air generated by the blower to the bottom of the filter module. In this way, the airflow can form a continuous scouring force on the fine impurities and floc residues attached to the outside of the membrane fibers, destroying the dense fouling layer formed by long-term filtration. Furthermore, the rising airflow during the gas scouring process can form a microflow field around the membrane fibers, reducing the probability of impurities re-attaching after backwashing.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: The dissolved air flotation and external pressure membrane integrated water treatment system of the present invention, by setting a partition in the dissolved air flotation tank to separate the dissolved air release zone and the filtration zone, integrates the dissolved air flotation and external pressure membrane filtration functions into the same equipment, reducing the footprint. Furthermore, the present invention sets the filtration membrane group into compartments. When a single membrane group is backwashed, the other membrane groups filter normally. Combined with the air-water backwashing of the blower and the suction pump, the operation and maintenance costs are reduced. In addition, the present invention improves the mixing uniformity of coagulant and raw water through the first or second agitator, forming flocs with uniform particle size and stable structure, enhancing the adhesion efficiency with the microbubbles in the dissolved air release zone, reducing the entry of unseparated impurities into the filtration zone, reducing the membrane group fouling load, and improving the overall treatment efficiency of the system. Attached Figure Description

[0021] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the air flotation external pressure membrane integrated water treatment system in Embodiment 1 of the present invention;

[0023] Figure 2 This is a schematic diagram of the internal structure of the air flotation tank in Embodiment 1 of the present invention;

[0024] Figure 3 This is a schematic diagram of the air flotation external pressure membrane integrated water treatment system in Embodiment 2 of the present invention;

[0025] Figure 4 This is a schematic diagram of the second agitator of the present invention installed in the mixing tank;

[0026] Figure 5 This is a schematic diagram of the second stirrer of the present invention from a first perspective.

[0027] Figure 6 This is a schematic diagram of the second stirrer of the present invention from a second perspective.

[0028] Figure 7 This is a schematic diagram showing the installation position of the separator in the dissolved gas release zone of the present invention;

[0029] Figure 8 This is a schematic diagram of the separator structure of the present invention;

[0030] Figure 9 This is a schematic diagram of the scum collector scheme of the present invention;

[0031] Figure 10This is a schematic diagram showing the connection between the end of the scum collector of the present invention and the flotation tank.

[0032] Explanation of reference numerals in the attached drawings: 10. Water collection tank; 11. First pipe body; 12. Suction pump; 20. Flotation tank; 21. Dissolved gas release zone; 22. Filter module; 23. Scum discharge collection plate; 24. Discharge trough; 25. Filter zone; 26. Separator; 261. Bending plate; 262. Elastic element; 27. Baffle plate; 30. Blower; 31. Second pipe body; 40. Air compressor; 41. Pressure dissolved gas tank; 42. Third pipe body; 50. Mixing tank; 60. First agitator; 70. Second agitator 71. Agitator; 72. First agitator frame; 73. Second agitator frame; 74. Connecting plate; 75. Second rotating shaft; 76. First rotating shaft; 77. Mounting base plate; 78. First drive motor; 79. Inlet opening; 710. Inclined plate; 711. First gear; 82. Second gear; 83. Scum collector; 84. Second drive motor; 85. Collection bucket; 86. Large-hole mesh plate; 87. Steel nail; 88. Collecting plate; 89. Main shaft; 80. Guide plate; 81. Bearing; 80. Discharge pipe. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] The concepts involved in this application will first be described with reference to the accompanying drawings. It should be noted that the following descriptions of various concepts are only for the purpose of making the content of this application easier to understand and do not constitute a limitation on the scope of protection of this application; furthermore, the embodiments and features in the embodiments of this application can be combined with each other unless otherwise specified. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0035] Example 1:

[0036] As shown in the attached figure Figure 1 -Appendix Figure 2As shown, the air flotation-based external pressure membrane integrated water treatment system includes an air flotation tank 20. A partition 27 divides the air flotation tank 20 into a dissolved air release zone 21 and a filtration zone 25. The dissolved air release zone 21 has an air inlet at its bottom and a liquid inlet on its side. The filtration zone 25 houses compartmentalized filter membrane modules 22. The upper part of each filter membrane module 22 is connected to a first tube 11. The filter membrane module 22 has a hollow structure and vertically arranged membrane fibers with uniformly distributed pores on the membrane fiber tube walls. A sludge discharge port is located at the bottom of the filtration zone 25 for timely discharge of deposited sludge. The filter membrane module 22 uses flat-plate ceramic membranes, which are arranged in a membrane module configuration. The membrane fibers form a flat-plate ceramic membrane, which is then integrated into a membrane module. The membrane fibers are external pressure membranes with a hollow structure and a large number of uniformly distributed pores with a diameter of 0.1 micrometers on the membrane fiber tube walls. The membrane filaments form vertically arranged submerged perforated water outlet pipes with an opening diameter of 0.1 micrometers.

[0037] The filter module 22 of the present invention is a ceramic membrane, but it can also be other membrane materials, such as traditional PVC ultrafiltration membrane. However, considering the micro sludge in plastic, it is recommended to use a ceramic membrane made of alumina or silicon carbide.

[0038] The entire water treatment system can be equipped with an automated control system to achieve real-time monitoring and automatic adjustment of the entire system, thereby improving the system's operating efficiency and stability.

[0039] This invention uses a partition 27 inside the flotation tank 20 to separate a dissolved air release zone 21 and a filtration zone 25, achieving integrated dissolved air flotation and membrane filtration to reduce land occupation and simplify the water treatment system. The dissolved air release zone 21 has an air inlet at the bottom and a liquid inlet on the side for media entry, enabling suspended solids to be separated by flotation. The filtration zone 25 is further divided into compartments of filter membrane assemblies 22, vertically arranged to form a submerged perforated outlet pipe. The first tube 11 at the top of the filter membrane assembly 22 facilitates the transport of produced water. During the discharge of filtered water from the flotation tank 20, the water flows out through the pores in the membrane fiber tube wall. This process helps to generate a uniform upward flow velocity in the flotation tank 20, and the fluid movement direction is consistent with the solid-liquid separation direction of the flotation. This not only achieves the discharge of purified water but also improves the solid-liquid separation efficiency and, by enhancing fluid movement, helps to reduce the probability of adhesion to the inner wall of the flotation tank 20.

[0040] The horizontal height of the baffle 27 is lower than that of the flotation tank 20, which is used to create a water level gradient. This allows the clear liquid after flotation separation in the dissolved air release zone 21 to naturally overflow into the filtration zone 25 without the need for additional power supply. At the same time, it prevents the water in the flotation tank 20 from overflowing, ensuring that the dissolved air release zone 21 has sufficient space to complete the floating and separation of suspended solids. Furthermore, the angle between the baffle 27 and the filtration zone 25 is smaller than the angle between the baffle 27 and the dissolved air release zone 21. On the one hand, this extends the residence time of the liquid in the dissolved air release zone 21, ensuring that the bubbles and suspended solids fully contact and adhere, thereby improving the flotation impurity removal efficiency. On the other hand, it guides the clarified liquid into the filtration zone 25 at a stable flow rate, avoiding water flow impacting the filter membrane module 22 and reducing the risk of unseparated impurities disturbing and contaminating the membrane fibers. It also helps to evenly distribute the liquid to the compartmentalized filter membrane module 22.

[0041] A water collection tank 10 is provided outside the flotation tank 20. The water collection tank 10 is connected to the filter membrane assembly 22 through a first pipe 11. The first pipe 11 receives the filtered water from the filter membrane assembly 22 and can supply water for backwashing when the filter membrane assembly 22 needs backwashing. A suction pump 12 is provided on the first pipe 11. Specifically, when the intermembrane pressure difference of the ceramic membrane reaches a certain value, rinsing is required. At this time, the scum generated by flotation is first scraped off, and the suction pump 12 is used to pressurize and transport it from the water collection tank 10 to the membrane fiber center tube. The water then enters the filtration zone 25 through the tiny pores on the membrane fiber, achieving water washing of the membrane fiber pores and surface, making the membrane fiber clean again. If necessary, the blower 30 is started to achieve air-water rinsing of the membrane fiber.

[0042] An air compressor 40 and a pressure dissolved air tank 41 are installed outside the dissolved air flotation tank 20. The air compressor 40 is connected to the pressure dissolved air tank 41, which is connected to the air inlet at the bottom of the dissolved air release zone 21 via a connecting pipe. The pressure dissolved air tank 41 is connected to the water collection tank 10 via a third pipe 42. The air compressor 40 inputs compressed air into the pressure dissolved air tank 41 and uses the filtered water from the water collection tank 10 transported by the third pipe 42. Within the pressure dissolved air tank 41, sufficient mass transfer and dissolution of air and water are achieved, forming high-concentration dissolved air water. This dissolved air water is then transported to the air inlet at the bottom of the dissolved air release zone 21 via the connecting pipe. After being depressurized by the release device, a large number of uniform microbubbles are generated, which can efficiently adhere to suspended solids in the water to form scum, improving the air flotation separation efficiency. Simultaneously, the clean water from the water collection tank 10 is used as the dissolved air water source, reducing the interference of raw water impurities on the dissolved air process and achieving water resource circulation within the system, thus reducing the filtration pressure on the subsequent filter membrane module 22.

[0043] A mixing tank 50 is provided outside the flotation tank 20. The mixing tank 50 is connected to the liquid inlet on the side of the dissolved air release zone 21 through a connecting pipe. A first agitator 60 is provided on the mixing tank 50. The first agitator 60 has a stirring blade and a driving component installed in the mixing tank 50. The first agitator 60 on the mixing tank 50 can rotate under the drive of the driving component to fully mix the raw water and coagulant, so as to promote the formation of structurally stable flocs of suspended solids in the water. This solves the problem of floc breakage or insufficient formation caused by uneven mixing in traditional methods. After the water is fully mixed by the first agitator 60 enters the dissolved air release zone 21, it can efficiently combine with the microbubbles released from the dissolved air water input at the bottom air inlet, improve the floating and separation efficiency of suspended solids, and reduce the pollution of the filter membrane module 22 in the filtration zone 25 by unseparated impurities.

[0044] A blower 30 is installed outside the flotation tank 20, and the blower 30 is connected to the bottom of the filter module 22 through a second pipe 31. During backwashing, the second pipe 31 sends the compressed air generated by the blower 30 to the bottom of the filter module 22. In this way, the airflow can form a continuous scouring force on the fine impurities and floc residues attached to the outside of the membrane fibers, destroying the dense fouling layer formed by long-term filtration. In addition, the rising airflow during the gas scouring process can form a microflow field around the membrane fibers, reducing the probability of impurities re-attaching after backwashing.

[0045] Example 2:

[0046] In this embodiment, see Appendix Figure 3-10 As shown, the air flotation-based external pressure membrane integrated water treatment system includes an air flotation tank 20. A partition 27 divides the air flotation tank 20 into a dissolved air release zone 21 and a filtration zone 25. The dissolved air release zone 21 has an air inlet at its bottom and a liquid inlet on its side. The filtration zone 25 houses compartmentalized filter membrane modules 22. The upper part of each filter membrane module 22 is connected to a first tube 11. The filter membrane module 22 has a hollow structure and vertically arranged membrane fibers with uniformly distributed pores on the membrane fiber tube walls. A sludge discharge port is located at the bottom of the filtration zone 25 for timely discharge of deposited sludge. The filter membrane module 22 uses flat-plate ceramic membranes, which are arranged in a membrane module configuration. The membrane fibers form a flat-plate ceramic membrane, which is then integrated into a membrane module. The membrane fibers are external pressure membranes with a hollow structure and a large number of uniformly distributed pores with a diameter of 0.1 micrometers on the membrane fiber tube walls. The membrane filaments form vertically arranged submerged perforated water outlet pipes with an opening diameter of 0.1 micrometers.

[0047] A separator 26 is provided within the dissolved gas release zone 21. The separator 26 is located at the bottom air inlet of the dissolved gas release zone 21, and its horizontal height is lower than that of the liquid inlet on the side of the dissolved gas release zone 21. The separator 26 includes bent plates 261 arranged at intervals in sequence. The bent plates 261 are connected by elastic members 262. The bent plates 261 at the edge of the separator 26 are connected to the flotation tank 20 by fasteners. The bent plate 261 includes a first plate and a second plate, and there is an included angle between the first plate and the second plate. The first and second plates of the bending plate 261 form an angle to guide the dissolved air and water released from the air inlet in different directions. Combined with the spaced arrangement, this solves the problem of concentrated release and easy aggregation of bubbles, and achieves uniform distribution of microbubbles in the dissolved air release zone 21. Furthermore, the bending plates 261 are connected by elastic members 262, which can undergo slight deformation with the impact of water flow. This avoids water flow obstruction caused by rigid connection and can further disperse bubbles through elastic vibration. In addition, the horizontal height of the separator 26 is lower than the side inlet of the dissolved air release zone 21. This allows the water pretreated by the mixing tank 50 to flow through the area above the separator 26 after entering from the inlet, forming a cross-flow contact state with the microbubbles dispersed by the separator. That is, the raw water flows from top to bottom, and the bubbles float from bottom to top, prolonging the contact time between the two and ensuring that the bubbles fully adhere to the flocs and suspended solids in the raw water. This solves the problem of bubble breakage or insufficient contact caused by the water directly impacting the bubbles at the air inlet.

[0048] A mixing tank 50 is provided outside the flotation tank 20. The mixing tank 50 is connected to the liquid inlet on the side of the dissolved gas release zone 21 through a connecting pipe. A second stirrer 70 is provided on the mixing tank 50. The second stirrer 70 includes a mounting base plate 76 fixedly installed on the mixing tank 50. A first rotating shaft 75 and a second rotating shaft 74 that can rotate are respectively provided on the mounting base plate 76. The axes of the first rotating shaft 75 and the second rotating shaft 74 are parallel to the liquid outlet direction of the mixing tank 50. A first stirring frame 71 is provided on the first rotating shaft 75, and a second stirring frame 72 is provided on the second rotating shaft 74.

[0049] The axes of the first rotating shaft 75 and the second rotating shaft 74 are parallel to the liquid outlet direction of the mixing tank 50, so that the stirring direction of the first stirring frame 71 and the second stirring frame 72 is consistent with the water flow direction, solving the problem of water flow obstruction in traditional vertical stirring. Furthermore, when the first stirring frame 71 and the second stirring frame 72 rotate synchronously, they can cover a larger cross section of the mixing tank 50, avoiding stirring dead corners, and can also cooperate with the frame structure to cut and disturb the water flow, so that the coagulant and water are quickly mixed.

[0050] A second gear 711 is provided on the mounting base plate 76. A first drive motor 77 connected to the second gear 711 is provided on one side of the mounting base plate 76. First gears 710 are symmetrically arranged on both sides of the second gear 711. One first gear 710 is coaxially connected to the first rotating shaft 75, and the other first gear 710 is coaxially connected to the second rotating shaft 74. The second gear 711 on the mounting base plate 76 rotates under the drive of the first drive motor 77. Through the symmetrical meshing of the first gears 710 on both sides, the coaxial first rotating shaft 75 and second rotating shaft 74 are synchronously driven to rotate, ensuring that the rotation speed of the first rotating shaft 75 and the second rotating shaft 74 is consistent, avoiding the asynchronous stirring caused by traditional independent drive.

[0051] The horizontal planes of the first stirring frame 71 and the second stirring frame 72 are at an angle, and the inner lining of the frame structure of the first stirring frame 71 and the second stirring frame 72 are provided with inclined plates 79 arranged at intervals.

[0052] The ends of the first rotating shaft 75 and the second rotating shaft 74 are rotatably connected to a connecting plate 73. The first stirring frame 71 and the second stirring frame 72 are rectangular frame structures. The first stirring frame 71 and the second stirring frame 72 adopt a rectangular structure and have an angle between their horizontal planes, which can form a three-dimensional cross disturbance when they are stirring. Compared with the single plane stirring method, this can better solve the problem of water flow stratification and avoid mixing dead corners. When the first stirring frame 71 and the second stirring frame 72 rotate synchronously with the first rotating shaft 75 and the second rotating shaft 74, the water flow will come into contact with the inclined plate 79 multiple times. In this way, the inclined plate 79 can cut the water flow. This not only realizes the propulsion of the water body, but also guides the water flow to form multiple small eddies through the tilt angle of the inclined plate 79 itself, so as to promote the dispersion of coagulant particles from a local aggregated state to a uniform suspension state, thus solving the problem of uneven coagulant dispersion.

[0053] Furthermore, the connecting plate 73 at the ends of the first rotating shaft 75 and the second rotating shaft 74 further reinforces the first rotating shaft 75 and the second rotating shaft 74, preventing the frame from shifting due to vibration during rotation and improving the overall operational stability.

[0054] The mounting base plate 76 has an inlet opening 78, and the mixing tank 50 has an inlet hole communicating with the inlet opening 78 and an inlet pipe on one side, and a valve is provided on the inlet pipe.

[0055] See appendix Figure 3 As shown, the flotation tank 20 has an opening above it and a scum collector 80 is provided above it. A scum discharge collection plate is provided above the flotation tank 20, and a discharge trough 24 is provided on one side of the flotation tank 20 for collecting scum. A discharge port is provided at the bottom of the discharge trough 24 for discharging scum.

[0056] The scum collector 80 includes a cylindrical collection tank 82, with a main shaft 86 coaxial with the center of the collection tank 82. Large-hole mesh plates 83 are spaced apart inside the collection tank 82, and the main shaft 86 is connected to the large-hole mesh plates 83. The surface of the large-hole mesh plates 83 is provided with through holes, and the main shaft 86 is fixedly connected to the collection tank 82 through the large-hole mesh plates 83. A second drive motor 81 connected to the main shaft 86 is provided outside the flotation tank 20. Openings communicating with the interior are arranged around the surface of the collection tank 82 at intervals, and steel nails 84 are provided on the collection tank 82 on one side of the opening. A collection plate 85 is spaced apart above the opening, and one end of the collection plate 85 is connected to the collection tank 82. The medium can enter the opening under the guidance of the collection plate 85.

[0057] A guide plate 87 is arranged around the side of the main shaft 86, and the guide plate 87 is connected and fixed to the side of the large-hole mesh plate 83.

[0058] During the scum collection process, the second drive motor 81 drives the main shaft 86 to rotate. The openings around the surface of the collection bucket 82 serve as channels for scum to enter. The collecting plate 85 above the openings can guide the scum on the surface of the flotation tank to converge towards the openings through an inclined angle, preventing the scum from spreading with the water flow. The steel nails 84 on one side of the openings help to break the sticky film on the surface of the scum, preventing the scum from sticking to the outer wall of the collection bucket and ensuring that the scum enters the bucket smoothly. Furthermore, the guide plate 87 around the side of the main shaft 86 pushes the scum in the bucket towards the discharge end when the main shaft rotates, preventing the scum from accumulating and clogging in the bucket. After entering the discharge trough 24, the scum is discharged from the bottom, preventing secondary pollution of the water in the flotation tank 20 by the scum. At the same time, the through holes of the large-pore mesh plate 83 can filter the excess water carried in the scum and reduce the moisture content of the scum.

[0059] The flotation tank 20 on one side of the discharge trough 24 has a mounting hole that allows the main shaft 86 of the scum collector 80 to pass through. A bearing 88 is installed in the mounting hole, and a discharge pipe 89 is interference-fitted to the inner ring of the bearing 88. The discharge pipe 89 is connected to the main shaft 86 through a large-hole mesh plate 83. The bearing 88 is used to ensure that the main shaft 86 drives the collection tank 82 to rotate smoothly, avoiding the impact of jamming on the scum collection efficiency. Furthermore, the connection between the discharge pipe 89 and the large-hole mesh plate 83 allows the scum in the collection tank 82 to be transported to the discharge trough 24, preventing scum from accumulating and clogging.

[0060] Example 3:

[0061] In this embodiment, see Appendix Figure 1 Appendix Figure 2As shown, a scum discharge and collection plate is provided above the flotation tank 20, and a discharge trough 24 is provided on one side of the flotation tank 20 for collecting scum. A discharge port is provided at the bottom of the discharge trough 24 for discharging scum. The scum discharge and collection plate above the flotation tank 20 is used to collect the scum generated by flotation, preventing the scum from spreading with the water flow into the filtration zone 25 inside the flotation tank 20, and preventing secondary pollution of the water to be filtered by the scum.

[0062] Example 4:

[0063] In this embodiment, a first agitator 60 is provided on the water collection tank 10. The first agitator 60 has a stirring blade and a driving component, which is a motor, disposed within the water collection tank 10. The stirring blade of the first agitator 60 on the water collection tank 10 rotates under the drive of the motor driving component, which is used to prevent impurities from accumulating and mud from forming at the bottom of the water collection tank 10.

[0064] Example 5:

[0065] The system of this invention can be integrated into a container to form a mobile integrated water production system, which enables the system to be quickly deployed to where it is needed. It is particularly suitable for emergency response scenarios, such as temporary water supply after natural disasters and temporary water supply in remote areas.

[0066] Example 6:

[0067] In this embodiment, depending on the quality of the raw water, when the organic matter content in the incoming water is high, the air source in the dissolved gas can be replaced with an ozone source.

[0068] It should also be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application 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, and therefore should not be construed as a limitation on this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," "linked," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0069] The embodiments and / or implementation methods described above are merely preferred embodiments and / or implementation methods for implementing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any way. Any person skilled in the art can make some modifications or alterations to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as the technology or embodiments that are substantially the same as the present invention.

[0070] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. An integrated air flotation and external pressure membrane water treatment system, characterized in that: The system includes an air flotation tank (20), which is provided with a partition (27) to divide the air flotation tank (20) into a dissolved gas release zone (21) and a filtration zone (25). The dissolved gas release zone (21) has an air inlet at the bottom and a liquid inlet on the side. The filtration zone (25) is equipped with a filter membrane assembly (22) arranged in compartments. The filter membrane assembly (22) is connected to a first tube (11) at the top. The filter membrane assembly (22) has a hollow structure and is composed of vertically arranged membrane filaments. Fine pores are evenly distributed on the wall of the membrane filament tube. The air flotation tank (20) is provided with a water collection tank (10) outside. The water collection tank (10) is connected to the filter membrane group (22) through a first pipe (11). A suction pump (12) is provided on the first pipe (11). An air compressor (40) and a pressure dissolved gas tank (41) are provided outside the flotation tank (20). The air compressor (40) is connected to the pressure dissolved gas tank (41), and the pressure dissolved gas tank (41) is connected to the air inlet at the bottom of the dissolved gas release area (21) through a connecting pipeline. The air flotation tank (20) is equipped with a blower (30), which is connected to the bottom of the filter module (22) through a second pipe (31).

2. The integrated air flotation and external pressure membrane water treatment system according to claim 1, characterized in that, The horizontal height of the partition (27) is lower than that of the flotation tank (20), and the angle between the partition (27) and the filtration zone (25) is smaller than the angle between the partition (27) and the dissolved gas release zone (21).

3. The integrated air flotation and external pressure membrane water treatment system according to claim 1, characterized in that, The flotation tank (20) is provided with a mixing tank (50) outside. The mixing tank (50) is connected to the liquid inlet on the side of the dissolved gas release zone (21) through a connecting pipe. The mixing tank (50) is provided with a first agitator (60). The first agitator (60) has a stirring blade and a driving component installed in the mixing tank (50).

4. The integrated air flotation and external pressure membrane water treatment system according to claim 3, characterized in that, The dissolved gas release zone (21) is provided with a separator (26), which is located on the bottom air inlet of the dissolved gas release zone (21), and the horizontal height of the separator (26) is lower than the liquid inlet on the side of the dissolved gas release zone (21).

5. The integrated air flotation and external pressure membrane water treatment system according to claim 1, characterized in that, The flotation tank (20) is provided with a mixing tank (50) outside. The mixing tank (50) is connected to the liquid inlet on the side of the dissolved gas release zone (21) through a connecting pipe. The mixing tank (50) is provided with a second stirrer (70). The second stirrer (70) includes a mounting base plate (76) fixedly installed on the mixing tank (50). The mounting base plate (76) is provided with a first rotating shaft (75) and a second rotating shaft (74) that can rotate. The axes of the first rotating shaft (75) and the second rotating shaft (74) are parallel to the liquid outlet direction of the mixing tank (50). The first rotating shaft (75) is provided with a first stirring frame (71), and the second rotating shaft (74) is provided with a second stirring frame (72).

6. The air flotation external pressure membrane integrated water treatment system according to claim 5, characterized in that, The mounting base plate (76) is provided with a second gear (711). A first drive motor (77) connected to the second gear (711) is provided on one side of the mounting base plate (76). First gears (710) are symmetrically provided on both sides of the second gear (711). One of the first gears (710) is coaxially connected to the first rotating shaft (75), and the other first gear (710) is coaxially connected to the second rotating shaft (74).

7. The air flotation external pressure membrane integrated water treatment system according to claim 6, characterized in that, The horizontal planes of the first stirring frame (71) and the second stirring frame (72) have an angle between them, and the inner lining of the frame structure of the first stirring frame (71) and the second stirring frame (72) are provided with inclined plates (79) arranged at intervals in sequence.

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