Reinforced membrane hanging type hollow fiber membrane stack for MABR (Membrane Aerated Baffled Reactor) process

Abstract

The invention relates to the technical field of sewage treatment equipment, in particular to a reinforced biofilm culturing type hollow fiber membrane stack for an MABR process. The membrane comprises a membrane shell, a plurality of groups of membrane elements are arranged in the membrane shell, each membrane element consists of a plurality of hollow fiber membranes which are arranged in parallel, the upper end and the lower end of each membrane element are respectively connected with a membrane frame and are arranged in the membrane shell through the membrane frames, and a three-dimensional net-shaped filler layer is arranged between every two adjacent hollow fiber membranes; an additional biological attachment carrier is provided by adopting the three-dimensional net-shaped filler, so that the system can maintain higher microorganism concentration, the treatment capacity and the impact load resistance are stronger, and the biomass is obviously improved; the inclined aeration is adopted, so that bubbles are more fully contacted with a membrane, a filler and a liquid phase, the oxygen utilization rate and the pollutant degradation rate are improved, and the mass transfer efficiency is optimized; in the application, the directional transverse shearing force can more effectively control the thickness of a biological membrane on the surface of the membrane, reduce membrane pollution, prolong the cleaning period and the service life of the membrane, and enhance the anti-pollution performance.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment equipment technology, and specifically to a reinforced biofilm-attached hollow fiber membrane stack for MABR process. Background Technology

[0002] MABR technology is a highly efficient, low-energy wastewater treatment technology. Its core component is a hollow fiber membrane stack. In the MABR process, oxygen diffuses through the micropores of the hollow fiber membrane to the outside of the membrane, forming an aerobic biofilm on the membrane surface. Wastewater flows outside the membrane, and pollutants are degraded by the biofilm. This bubble-free aeration method has extremely high oxygen utilization.

[0003] However, existing MABR membrane stacks have certain shortcomings: (1) The biofilm mainly adheres to a limited membrane surface, and the total biomass is limited, which restricts the further increase of the treatment load; (2) In order to control membrane fouling, an aeration system needs to be installed at the bottom of the membrane stack for scrubbing. However, the shear force generated by the traditional vertical upward aeration method is unevenly distributed, resulting in poor scrubbing effect on the middle area of ​​the membrane. In addition, the bubble path is short, which has limited effect on the overall mixing and mass transfer of the reactor.

[0004] Therefore, there is an urgent need for a MABR membrane stack structure that can increase biofilm formation while optimizing aeration and scrubbing effects to improve overall performance. Summary of the Invention

[0005] The purpose of this invention is to address the deficiencies and shortcomings of existing technologies by providing a rationally designed reinforced attached hollow fiber membrane stack for MABR processes, which can solve the aforementioned deficiencies.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: it includes a membrane shell, and a number of membrane elements are provided inside the membrane shell. The membrane elements are composed of multiple hollow fiber membrane sheets arranged in parallel, and their upper and lower ends are respectively connected to membrane frames and installed inside the membrane shell through the membrane frames. A three-dimensional mesh filler layer is provided between adjacent hollow fiber membrane sheets.

[0007] Preferably, the bottom of the membrane shell is provided with an aeration mechanism, which includes an aeration pipe and a plurality of aeration heads, all of which are inclined upward.

[0008] Preferably, the material of the three-dimensional mesh filler layer is composed of one of polyethylene, polypropylene, polyamide or polyurethane.

[0009] Preferably, the edges of the three-dimensional mesh filler layer are connected to the diaphragm frame by straps or buckles.

[0010] Preferably, the three-dimensional mesh packing layer is one of elastic three-dimensional mesh packing, Pall ring packing, or volcanic rock fiber braided packing.

[0011] Preferably, the three-dimensional mesh filler layer fills the gaps between the hollow fiber membranes.

[0012] Preferably, all hollow fiber membranes are arranged vertically.

[0013] Preferably, the angle between the opening direction of the aeration head and the hollow fiber membrane is in the range of 15 degrees to 75 degrees.

[0014] Preferably, the angle between the opening direction of the aeration head and the hollow fiber membrane is in the range of 30 degrees to 60 degrees.

[0015] Preferably, the membrane shell is cylindrical or cuboid in shape.

[0016] The beneficial effects of the present invention after adopting the above structure are: 1. This application uses a three-dimensional mesh packing material to provide an additional biological attachment carrier, enabling the system to maintain a higher microbial concentration, stronger processing capacity and resistance to shock loads, and significantly improved biomass.

[0017] 2. This application uses inclined aeration to make the contact between bubbles and membranes, packing materials and liquid phase more sufficient, thereby improving oxygen utilization and pollutant degradation rate and optimizing mass transfer efficiency.

[0018] 3. In this application, the directional transverse shear force can more effectively control the thickness of the biofilm on the membrane surface, reduce membrane fouling, extend the membrane cleaning cycle and service life, and enhance the antifouling performance.

[0019] 4. This application has a simple structure and is easy to implement. It only adds filler and adjusts the aeration direction on the existing membrane stack structure. The modification cost is low and it is easy to promote and apply in existing products or projects. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the membrane stack in this invention; Figure 2 This is a partial side view of the membrane element in this invention; Figure 3 This is a top-view structural diagram of the aeration pipe in this invention; Figure 4 This is a schematic diagram showing the angle between the aeration direction and the membrane plane in this invention.

[0021] Explanation of reference numerals in the attached figures: 1. Membrane shell; 2. Membrane element; 21. Hollow fiber membrane; 22. Membrane frame; 3. Three-dimensional mesh packing layer; 4. Aeration mechanism; 41. Aeration pipe; 42. Aeration head. Detailed Implementation

[0022] 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.

[0023] See Figures 1-3 As shown, it includes a membrane shell 1. In this embodiment, the membrane shell 1 is cuboid in shape. The membrane shell 1 contains several sets of membrane elements 2. The membrane elements 2 are composed of multiple hollow fiber membrane sheets 21 arranged in parallel. The hollow fiber membrane sheets 21 are all vertically arranged, and their upper and lower ends are respectively connected to membrane frames 22. They are installed in the membrane shell 1 through the membrane frames 22. A three-dimensional mesh packing layer 3 is provided between adjacent hollow fiber membrane sheets 21. The bottom of the membrane shell 1 is provided with an aeration mechanism 4. The aeration mechanism 4 includes an aeration pipe 41 and several evenly distributed aeration heads 42. The aeration heads 42 are all inclined upward. The material of the three-dimensional mesh packing layer 3 is made of one of polyethylene, polypropylene, polyamide or polyurethane. The edge of the three-dimensional mesh packing layer 3 is connected to the membrane frame 22 by nylon cable ties for positioning. The thickness of the packing layer is less than the spacing between the membranes to ensure that the filling space can be reused without excessive compression that would affect the water flow and air flow. The cable tie installation is simple and convenient. The angle between the opening direction of the aeration head 42 and the hollow fiber membrane 21 is 45 degrees, that is, the angle α is 225 degrees. An angle between 30-60° can achieve a balance between scrubbing and mass transfer, so 45° is chosen. An angle between 15-75° can maintain normal operation, so this is also acceptable. Figure 4 During aeration, the bubbles rise obliquely upwards while moving laterally, creating a lateral scouring force on the surface of the hollow fiber membrane 21. At the same time, they pass obliquely through the reaction zone between the hollow fiber membrane 21 and the three-dimensional mesh packing layer 3, which greatly improves the mixing and mass transfer effect.

[0024] In actual operation, oxygen is supplied from inside the membrane filaments, forming an aerobic biofilm on the membrane surface. At the same time, a large number of facultative and anaerobic bacteria attach to the three-dimensional mesh packing layer 3, forming a complete micro-ecological environment, realizing advanced treatment functions such as simultaneous nitrification and denitrification. The inclined aeration at the bottom ensures the long-term stable and efficient operation of the entire system.

[0025] Example 2: Compared with the above embodiment one, the difference in this embodiment is that: the three-dimensional mesh packing layer 3 is one of elastic three-dimensional mesh packing, Pall ring packing or volcanic rock fiber braided packing, that is, the packing layer is formed in the form of packing. The three-dimensional mesh packing layer 3 fills the gaps between the hollow fiber membranes 21 to form packing. Compared with the above-mentioned integrated packing layer, this method has lower cost, smaller fluid pressure drop, and is more convenient to install and replace. There is no need to consider installation angle and fixing issues, and maintenance is convenient.

[0026] The installation, connection, or setting methods of the components not detailed above are all common mechanical methods, and the specific structure, model, and coefficient indicators of all their components are their own technologies. As long as they can achieve their beneficial effects, they can be implemented, so they will not be elaborated further.

[0027] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of the invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the invention should be included within the protection scope of the invention. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. A reinforced attached hollow fiber membrane stack for MABR process, comprising a membrane shell (1), characterized in that: The membrane shell (1) is provided with several sets of membrane elements (2). Each membrane element (2) consists of multiple hollow fiber membrane sheets (21) arranged in parallel, and its upper and lower ends are respectively connected to membrane frames (22). It is installed in the membrane shell (1) through the membrane frames (22). A three-dimensional mesh filler layer (3) is provided between adjacent hollow fiber membrane sheets (21).

2. The reinforced attached hollow fiber membrane stack for MABR process according to claim 1, characterized in that: The membrane shell (1) is provided with an aeration mechanism (4) at the bottom. The aeration mechanism (4) includes an aeration pipe (41) and several aeration heads (42). All aeration heads (42) are inclined upward.

3. The reinforced attached hollow fiber membrane stack for MABR process according to claim 1, characterized in that: The material of the three-dimensional mesh filler layer (3) is composed of one of polyethylene, polypropylene, polyamide or polyurethane.

4. A reinforced attached hollow fiber membrane stack for MABR process according to claim 3, characterized in that: The edge of the three-dimensional mesh filler layer (3) is connected to the diaphragm frame (22) by straps or buckles.

5. A reinforced attached hollow fiber membrane stack for MABR process according to claim 1, characterized in that: The three-dimensional mesh packing layer (3) is one of elastic three-dimensional mesh packing, Pall ring packing or volcanic rock fiber braided packing.

6. A reinforced attached hollow fiber membrane stack for MABR process according to claim 5, characterized in that: The three-dimensional mesh filler layer (3) fills the gaps between the hollow fiber membranes (21).

7. A reinforced attached hollow fiber membrane stack for MABR process according to claim 2, characterized in that: The angle between the opening direction of the aeration head (42) and the hollow fiber membrane (21) ranges from 15 degrees to 75 degrees.

8. A reinforced attached hollow fiber membrane stack for MABR process according to claim 7, characterized in that: The angle between the opening direction of the aeration head (42) and the hollow fiber membrane (21) is between 30 degrees and 60 degrees.

9. A reinforced attached hollow fiber membrane stack for MABR process according to claim 1, characterized in that: All hollow fiber membranes (21) are vertically arranged.

10. A reinforced attached hollow fiber membrane stack for MABR process according to claim 1, characterized in that: The membrane shell (1) is cylindrical or cuboid.

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