An aeration device for a hollow fiber membrane module

Abstract

The application discloses an aeration device of a hollow fiber membrane assembly, which comprises a support, a driving mechanism, a sliding seat and an aeration head; the support comprises a gas pipe, an inner cylinder and an outer cylinder which are sequentially arranged from inside to outside; the gas pipe, the inner cylinder and the outer cylinder are fixedly connected together through a plurality of radial partitions which are arranged in a circumferential direction around the gas pipe; two adjacent radial partitions form an installation space between the inner cylinder and the outer cylinder; the lower end of a membrane filament bundle of the hollow fiber membrane assembly is installed in the installation space; the aeration head is fixedly connected to the upper side of the sliding seat; a first gas channel is arranged in the aeration head; gas outlets which are in communication with the first gas channel are arranged on the opposite sides of the upper end of the aeration head; the gas outlet gas direction is perpendicular to the radial partition; the lower end of the first gas channel penetrates to the lower side of the sliding seat; a gas storage cavity and a second gas channel are arranged on the upper side and the inner side of the radial partition respectively. The application provides an aeration device, so that the bubbles can deeply enter the interior of the membrane filament bundle to scrub the internal membrane filaments, and the scrubbing effect of the internal membrane filaments of the membrane filament bundle is improved.

Description

Technical Field

[0001] This invention relates to the field of hollow fiber membrane module technology, and in particular to an aeration device for a hollow fiber membrane module. Background Technology

[0002] Columnar hollow fiber membrane modules are a commonly used wastewater treatment device. The core of the device is to encapsulate hollow fiber membrane filaments with a specific pore size distribution in a columnar structure to form a standardized membrane module. Under pressure, it can achieve efficient separation of macromolecules (such as proteins, colloids, and suspended solids) from small molecule solvents and ions in the feed liquid.

[0003] During long-term wastewater treatment, a large number of microscopic pollutant particles will adhere to the outer surface of the membrane fibers in column-type hollow fiber membrane modules. If not cleaned in time, these pollutants, such as microorganisms and their high-viscosity metabolites, dissolved macromolecular organic matter, etc., will accumulate on the membrane surface, causing membrane fouling and reducing membrane filtration capacity. Therefore, it is necessary to remove pollutants from the surface of the membrane fibers regularly.

[0004] Existing hollow fiber membrane modules such as Figure 8 As shown, it includes a housing 91, a support 92, and membrane fibers. The membrane fibers are vertically and tightly packed in the housing to perform ultrafiltration. The support divides the membrane fibers into multiple circumferentially arranged fan-shaped membrane fiber bundles 93, such as... Figure 9 A vertical flow channel 94 is formed between two adjacent membrane fiber bundles 93. The existing hollow fiber membrane module has an aeration device 95 installed at the lower end of the flow channel. When rinsing the membrane fibers, the aeration device outputs air bubbles upward. The air bubbles move upward along the flow channel and form a gas-liquid mixture in the flow channel to achieve the scrubbing of the membrane fibers. However, since the membrane fibers in the membrane fiber bundle are arranged tightly, the gas-liquid mixture can only scrub the membrane fibers on the surface of the membrane fiber bundle, and cannot penetrate into the membrane fibers inside the membrane fiber bundle. Therefore, the cleaning effect on the membrane fibers inside the membrane fiber bundle is not good. Summary of the Invention

[0005] In order to solve the shortcomings of existing aeration devices where bubbles cannot penetrate deep into the membrane fiber bundle to clean the internal membrane fibers, this invention proposes an aeration device that allows bubbles to penetrate deep into the membrane fiber bundle to clean the internal membrane fibers, thereby improving the cleaning effect on the internal membrane fibers.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An aeration device for a hollow fiber membrane module includes a support, a drive mechanism, a sliding seat, and an aeration head; The support includes an air tube, an inner cylinder and an outer cylinder arranged sequentially from the inside to the outside. The air tube, the inner cylinder and the outer cylinder are fixedly connected together by multiple radial partitions arranged around the circumference of the air tube. Two adjacent radial partitions form an installation space between the inner cylinder and the outer cylinder. The lower end of the membrane bundle of the hollow fiber membrane module is installed in the installation space. The sliding seat is slidably connected to the upper side of the radial partition and is driven by a drive mechanism; The aeration head is fixedly connected to the upper side of the sliding seat. The aeration head is provided with a first air channel. The upper end of the aeration head is provided with air outlets on both sides that communicate with the first air channel. The air outlets are perpendicular to the radial partition. The lower end of the first air channel extends to the lower side of the sliding seat. An air storage chamber and a second air passage are respectively provided on the upper side and inside of the radial partition. The upper side of the air storage chamber is connected to the lower end of the first air passage, and the lower side of the air storage chamber is connected to the air pipe through the second air passage. The air blowing device blows air into the air pipe, and the air outlet at the upper end of the aeration head outputs bubbles in a pulse manner.

[0007] Furthermore, the aeration device also includes a pressure bar, the two ends of which are locked to the upper side of the radial partition. The pressure bar slides in conjunction with the upper side of the sliding seat, and the pressure bar is provided with a clearance opening for avoiding the aeration head.

[0008] Furthermore, the drive mechanism includes a turntable, a connecting rod, and a motor. The turntable includes a central component and a connecting component. The central component is rotatably connected to the upper end of the airway and is driven by the motor. One end of the connecting component is radially fixed to the central component. One end of the connecting rod is hinged to the sliding seat, and the other end is connected to the connecting component.

[0009] Furthermore, the turntable also includes a circular component located on the upper side of the inner cylinder, with the end of the connector away from the central component being fixedly connected to the circular component.

[0010] Furthermore, the drive mechanism also includes a rotating tube, which is rotatably connected in the air pipe. The lower end of the rotating tube is connected to the motor drive, and the upper end of the rotating tube is fixedly connected to the central component. An annular groove is provided along the inner circumference of the air pipe, and the second air passage is connected to the annular groove. The rotating tube is provided with an air hole, and the rotating tube is connected to the annular groove through the air hole.

[0011] Furthermore, the drive mechanism also includes an encoder installed between the rotating tube and the bracket.

[0012] Furthermore, a first annular mounting groove and a second annular mounting groove are provided on the inner circumference of the trachea. The first annular mounting groove and the second annular mounting groove are respectively located on the upper and lower sides of the annular groove, and sealing rings are installed in the first annular mounting groove and the second annular mounting groove.

[0013] Furthermore, the bracket is made of PVDF material.

[0014] Furthermore, the diameter of the air outlet is 0.8-1.2mm.

[0015] Furthermore, each sliding seat is provided with at least four aeration heads at equal intervals.

[0016] Through the above improvements, the aeration device of the present invention has the following beneficial effects: 1. The air outlet at the upper end of the aeration pipe outputs air bubbles laterally, which can penetrate deeper into the membrane fiber bundle and scrub the membrane fibers inside the bundle; 2. The pulsed jet of air bubbles allows low-pressure gas to be ejected in a high-pressure form, which saves energy on the one hand, and facilitates the air bubbles to penetrate deeper into the membrane fiber bundle and scrub the membrane fibers inside the bundle on the other hand; 3. The sliding seat can slide radially to cover more membrane fibers and further improve the scrubbing effect. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the aeration device in an embodiment.

[0018] Figure 2 for Figure 1 Enlarged view of point A.

[0019] Figure 3 This is a top view of the aeration device in an embodiment.

[0020] Figure 4 for Figure 3 BB cross-sectional view.

[0021] Figure 5 for Figure 4 Enlarged view of point C.

[0022] Figure 6 This is a schematic diagram of the aeration device in an embodiment discharging air bubbles into the membrane fiber bundle.

[0023] Figure 7 This is a schematic diagram of the turntable rotation as shown in the embodiment.

[0024] Figure 8 This is a cross-sectional view of an existing hollow fiber membrane module.

[0025] Figure 9 This is a schematic diagram of the aeration process for an existing hollow fiber membrane module. Detailed Implementation

[0026] The technical solution of the present invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings.

[0027] like Figures 1 to 7This invention proposes an aeration device for a hollow fiber membrane module, used for aeration and rinsing of cylindrical hollow fiber membrane modules. The aeration device includes a support 3, a drive mechanism, a sliding seat 4, and an aeration head 5. The support 3 includes an air pipe 31, an inner cylinder 32, and an outer cylinder 33 arranged sequentially from the inside to the outside. The outer circumferential surface of the outer cylinder 33 mates with the inner circumferential surface of the lower end of the outer shell of the hollow fiber membrane module. The inner cylinder 32 is coaxially arranged inside the outer cylinder 33, and the air pipe 31 is coaxially arranged inside the inner cylinder 32. The air pipe 31, the inner cylinder 32, and the outer cylinder 33 are fixedly connected by multiple radial partitions 34 arranged circumferentially around the air pipe 31. In this embodiment, six radial partitions 34 are specifically provided. The radial partitions 34 extend radially and are arranged at equal intervals around the circumference of the air tube 31. The radial partitions 34, the air tube 31, the inner cylinder 32 and the upper side of the outer cylinder 33 are flush. Two adjacent radial partitions 34 form an installation space 6 between the inner cylinder 32 and the outer cylinder 33. The membrane filaments 200 of the hollow fiber membrane module are tightly packed in the outer shell of the hollow fiber membrane module to form a membrane filament bundle. The lower end of the membrane filament bundle of the hollow fiber membrane module is installed in the installation space 6. The radial partitions 34 separate two adjacent membrane filament bundles, and a vertical flow channel is formed between two adjacent membrane filament bundles. The sliding seat 4 is sealed and slidably connected to the upper side of the radial partition 34. There is no air leakage between the lower side of the sliding seat 4 and the upper side of the radial partition 34. Under the action of the driving mechanism, the sliding seat 4 can slide radially along the upper side of the radial partition 34. The width of the sliding seat 4 is less than the thickness of the radial partition 34 to prevent the sliding seat 4 from contacting the membrane filament. The aeration head 5 is fixedly connected to the upper side of the sliding seat 4. Multiple aeration heads 5 are arranged radially on the upper side of each sliding seat 4 to increase the aeration coverage area. The aeration head 5 has a first air passage 7 inside, and air outlets 8 connected to the first air passage 7 are provided on opposite sides of the upper end of the aeration head 5. Figure 6 The air outlet 8 is perpendicular to the radial partition 34 so that the bubbles can penetrate deep into the membrane fiber bundle. The lower end of the first air channel 7 extends to the lower side of the sliding seat 4. Multiple air storage chambers 9 are provided on the upper side of the radial partition 34. Each air storage chamber 9 corresponds one-to-one with a first air passage 7 of aeration heads 5. The upper side of each air storage chamber 9 is connected to the lower end of the corresponding first air passage 7. The width of the air storage chamber 9 is greater than the width of the first air passage 7. This allows for a larger volume of the air storage chamber 9, facilitating pressure stabilization and air storage. Furthermore, it ensures that the first air passage 7 remains connected to the air storage chamber 9 during the movement of the sliding seat 4. A second air passage 10 is provided inside the radial partition 34. The diameter of the second air passage 10 is smaller than the width of the air storage chamber 9. One end of the second air passage 10 is connected to the lower end of the air storage chamber 9, and the other end is connected to the air pipe 31. Figure 4 When multiple air storage chambers 9 are provided on the upper side of the radial partition 34, the multiple air storage chambers 9 are connected in series on the second air passage 10, and the inner diameter of the air pipe 31 is large so as to smoothly deliver gas to the air pipe 31. The aeration device operates as follows: It is installed at the bottom of the hollow fiber membrane module's outer shell. The lower end of the membrane fiber bundle is installed in the installation space 6. Adjacent membrane fiber bundles are separated by radial partitions 34, forming a vertical flow channel between them. Aeration heads 5 are positioned at the lower end of this vertical flow channel. When rinsing the membrane fibers, clean water is introduced into the lower end of the inner cylinder 32. The water moves upward, forming an upward flow in the vertical flow channel to wash away contaminants on the membrane fiber surface. An air blower is connected to the lower end of the air pipe 31. The air blower can... A low-pressure gas is supplied to the air pipe 31 by an air pump and a blower. The gas passes through the air pipe 31 and the second air passage 10 into the air storage chamber 9. The gas pressure in the air storage chamber 9 increases slowly. The diameter of the air outlet 8 is small, and the water outside the air outlet 8 has a large surface tension. When the gas pressure in the air storage chamber 9 is low, the air outlet 8 basically does not release gas. As the gas pressure in the air storage chamber 9 rises to the threshold, the gas pressure inside the air outlet 8 overcomes the surface tension of the water, and high-pressure gas is ejected outward. The resulting bubbles have better penetrating power. Figure 6 Some bubbles are injected into the inner side of the membrane fiber bundle, while others remain in the vertical flow channel. Under the action of buoyancy, the bubbles move upward along the membrane fiber to scrub the membrane fiber. In this embodiment, when the gas is ejected from the outlet 8, the air pressure in the gas storage chamber 9 is released and the air pressure drops. The outlet 8 stops ejecting air, and the aeration device continues to aerate the gas storage chamber 9 through the air pipe 31 and the second air channel 10 to increase the air pressure in the gas storage chamber 9 in preparation for the next ejection of bubbles from the aeration head 5. Finally, the effect of pulsed output of bubbles from the outlet 8 at the upper end of the aeration head 5 is achieved. In this embodiment, the time interval between two adjacent air bubbles output from the air outlet 8 is t1. t1 can be adjusted by changing the volume of the air storage chamber 9 or the diameter of the air outlet 8, or other parameters. The driving mechanism drives the sliding seat 4 to move along the upper side of the radial partition 34. Under the action of the driving mechanism, the sliding seat 4 moves closer to or further away from the air pipe 31. The stroke of the sliding seat 4 is L1, and the distance between two adjacent aeration heads 5 is L2, where L1 = L2. The driving mechanism drives the sliding seat 4 to move a distance of L1 / 2 every t1 interval. For example, if t1 is 10 seconds, at time zero, such as... Figure 4 With the sliding seat 4 at the outermost end, after 10 seconds, the drive mechanism drives the sliding seat 4 to move closer to the trachea 31 by a distance of L1 / 2, moving to the midpoint. After 10 seconds, the drive mechanism drives the sliding seat 4 to move further towards the trachea 31 by a distance of L1 / 2, moving the sliding seat 4 to the innermost end. After 10 seconds, the drive mechanism drives the sliding seat 4 to move away from the trachea 31 by a distance of L1 / 2, moving the sliding seat 4 to the midpoint. After another 10 seconds, the drive mechanism drives the sliding seat 4 to move away from the trachea 31 by a distance of L1 / 2, and the sliding seat 4 returns to the outermost end. This process repeats, with the sliding seat 4 moving back and forth. Through the above settings, the bubbles output by the aeration head 5 can cover more membrane fibers, resulting in more thorough rinsing.

[0028] In one embodiment, such as Figure 2The aeration device also includes a pressure strip 11, which extends radially. Both ends of the pressure strip 11 are locked to the upper side of the radial partition 34. The lower side of the pressure strip 11 is in contact with the upper side of the sliding seat 4, and the pressure strip 11 slides in contact with the upper side of the sliding seat 4, so that the lower side of the sliding seat 4 is in contact with the upper side of the radial partition 34, ensuring the sliding seal between the sliding seat 4 and the radial partition 34. The pressure strip 11 is provided with a clearance opening 12 for avoiding the aeration head 5.

[0029] In one embodiment, such as Figure 1 and Figure 3 and Figure 4 The drive mechanism includes a turntable 13, a connecting rod 14, and a motor (not shown in the figure). The turntable 13 includes a central component 131 and connecting components 132. The central component 131 is rotatably connected to the upper end of the air pipe 31 and is driven by the motor. The number of connecting components 132 is the same as the number of radial partitions 34. Each connecting component 132 corresponds to one radial partition 34 and is located on the upper side of the corresponding radial partition 34. One end of the connecting component 132 is radially fixedly connected to the central component 131. One end of the connecting rod 14 is hinged to the sliding seat 4, and the other end is connected to the connecting component 132. Figure 7 When the motor drives the turntable 13 to rotate clockwise, the connecting piece 132 of the turntable 13 drives the sliding seat 4 to move inward. When the motor drives the turntable 13 to rotate counterclockwise, the connecting piece 132 of the turntable 13 drives the sliding seat 4 to move outward through the connecting rod 14. The motor is specifically set as a servo motor to improve the motion accuracy of the sliding seat 4.

[0030] In one embodiment, such as Figure 1 The turntable 13 also includes a circular component 133 disposed on the upper side of the inner cylinder 32, and the end of the connecting component 132 away from the center component 131 is fixedly connected to the circular component 133. The turntable 13 is a one-piece molded structure, and the circular component 133 supports the end of the connecting component 132 away from the center component 131 to improve the stability of the connecting component 132 and reduce the deformation of the connecting component 132, thereby improving the movement stability of the sliding seat 4.

[0031] In one embodiment, such as Figure 4 The drive mechanism also includes a rotating tube 15, which is adapted to the air tube 31. The outer circumferential surface of the rotating tube 15 mates with the inner circumferential surface of the air tube 31 to prevent air leakage between the rotating tube 15 and the air tube 31. The rotating tube 15 is rotatably connected in the air tube 31. The lower end of the rotating tube 15 is connected to the motor drive. For example, a gear assembly 16 is provided on the outer circumference of the lower end of the rotating tube 15. The motor drives the rotating tube 15 through the gear assembly 16. The upper end of the rotating tube 15 is fixedly connected to the center piece 131. An annular groove 17 is provided along the inner circumference of the air tube 31. The annular groove 17 on the inner circumference of the air tube 31 is connected to the second air passage 10. The rotating tube 15 is provided with an air hole 18. The rotating tube 15 is connected to the annular groove 17 on the inner circumference of the air tube 31 through the air hole 18. With the above configuration, firstly, the motor is connected to the center part 131 of the turntable 13 via the rotating tube 15, so that the motor drives the turntable 13, and then drives the sliding seat 4 to move through the turntable 13 and the connecting rod 14; secondly, after the air blowing device is connected to the lower end of the rotating tube 15, it is convenient to replenish air to the air storage chamber 9 through the rotating tube 15, the air hole 18, the annular groove 17, and the second air passage 10.

[0032] In one embodiment, the drive mechanism further includes an encoder (not shown in the figure) installed between the rotating tube 15 and the bracket 3. The encoder can measure the rotation angle of the rotating tube 15 in order to control the rotation angle of the turntable 13, thereby facilitating the control of the movement distance of the sliding seat 4.

[0033] In one embodiment, such as Figure 5 The inner circumference of the air tube 31 is provided with a first annular mounting groove 19 and a second annular mounting groove 20. The first annular mounting groove 19 and the second annular mounting groove 20 are respectively located on the upper and lower sides of the annular groove 17. Sealing rings are installed in the first annular mounting groove 19 and the second annular mounting groove 20. Through the above arrangement, air leakage between the inner circumferential surface of the air tube 31 and the outer circumferential surface of the rotating tube 15 is prevented.

[0034] In one embodiment, the bracket 3 is made of PVDF material to improve the durability, corrosion resistance and stability of the bracket 3.

[0035] In one embodiment, the diameter of the air outlet 8 is 0.8-1.2 mm. With the above arrangement, the water outside the air outlet 8 has a large surface tension at the air outlet 8, and the air pressure in the air storage chamber 9 is basically leak-free before reaching the threshold.

[0036] In one embodiment, at least four aeration heads 5 are evenly spaced on each sliding seat 4. This arrangement allows more membrane fibers to be scrubbed by air bubbles, improving the aeration and scrubbing effect.

[0037] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. An aeration device for a hollow fiber membrane module, characterized in that, Includes a support frame, drive mechanism, sliding seat, and aeration head; The support includes an air tube, an inner cylinder and an outer cylinder arranged sequentially from the inside to the outside. The air tube, the inner cylinder and the outer cylinder are fixedly connected together by multiple radial partitions arranged around the circumference of the air tube. Two adjacent radial partitions form an installation space between the inner cylinder and the outer cylinder. The lower end of the membrane bundle of the hollow fiber membrane module is installed in the installation space. The sliding seat is slidably connected to the upper side of the radial partition and is driven by a drive mechanism; The aeration head is fixedly connected to the upper side of the sliding seat. The aeration head is provided with a first air channel. The upper end of the aeration head is provided with air outlets communicating with the first air channel on both sides. The air outlets are perpendicular to the radial partition. The lower end of the first air channel extends to the lower side of the sliding seat. The radial partition plate has an air storage chamber and a second air channel respectively on its upper side and inside. The upper side of the air storage chamber is connected to the lower end of the first air channel, and the lower side of the air storage chamber is connected to the air pipe through the second air channel. The air blowing device blows air into the air pipe, and the air outlet at the upper end of the aeration head outputs bubbles in a pulse manner.

2. The aeration device for a hollow fiber membrane module according to claim 1, characterized in that, The aeration device also includes a pressure bar, the two ends of which are locked to the upper side of the radial partition. The pressure bar slides in conjunction with the upper side of the sliding seat, and the pressure bar is provided with a clearance opening for avoiding the aeration head.

3. The aeration device for a hollow fiber membrane module according to claim 1, characterized in that, The driving mechanism includes a turntable, a connecting rod, and a motor. The turntable includes a central component and a connecting component. The central component is rotatably connected to the upper end of the airway and is driven by the motor. One end of the connecting component is radially fixed to the central component. One end of the connecting rod is hinged to the sliding seat, and the other end is connected to the connecting component.

4. The aeration device for a hollow fiber membrane module according to claim 3, characterized in that, The turntable also includes a circular component disposed on the upper side of the inner cylinder, and the end of the connecting component away from the central component is fixedly connected to the circular component.

5. The aeration device for a hollow fiber membrane module according to claim 3, characterized in that, The driving mechanism also includes a rotating tube, which is rotatably connected in the air pipe. The lower end of the rotating tube is connected to the motor drive, and the upper end of the rotating tube is fixedly connected to the central component. An annular groove is provided along the inner circumference of the air pipe. The second air passage is connected to the annular groove. The rotating tube is provided with an air hole, and the rotating tube is connected to the annular groove through the air hole.

6. The aeration device for a hollow fiber membrane module according to claim 5, characterized in that, The drive mechanism also includes an encoder installed between the rotating tube and the bracket.

7. The aeration device for a hollow fiber membrane module according to claim 5, characterized in that, The trachea is provided with a first annular mounting groove and a second annular mounting groove on its inner circumference. The first annular mounting groove and the second annular mounting groove are respectively located on the upper and lower sides of the annular groove. Sealing rings are installed in the first annular mounting groove and the second annular mounting groove.

8. The aeration device for a hollow fiber membrane module according to claim 1, characterized in that, The bracket is made of PVDF material.

9. The aeration device for a hollow fiber membrane module according to claim 1, characterized in that, The diameter of the air outlet is 0.8-1.2 mm.

10. An aeration device for a hollow fiber membrane module according to claim 1, characterized in that, Each of the sliding seats has at least four aeration heads spaced at equal intervals.

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