A kind of MABR membrane module integrated device for high ammonia nitrogen wastewater

Abstract

The application provides a MABR membrane assembly integrated device for high-ammonia-nitrogen wastewater, comprising: a reaction tank body which is an anoxic biological treatment tank; a membrane assembly unit which is immersed in the reaction tank body, the membrane assembly unit comprising a membrane frame and a plurality of flat sheet hollow fiber membranes fixed on the membrane frame; an aeration system comprising a fan, a main gas supply pipeline and a membrane internal aeration pipeline, the fan being in communication with the hollow cavities of the flat sheet hollow fiber membranes through the main gas supply pipeline and the membrane internal aeration pipeline, and being used for providing bubbleless aeration in the membranes; a control system connected with the aeration system and used for controlling aeration parameters; the material of the flat sheet hollow fiber membranes is PVDF, and the aeration system further comprises a gas flow meter. The application utilizes the reverse diffusion mechanism to simultaneously perform nitrification and denitrification on the membrane surface, and effectively solves the problems of low denitrification efficiency, high carbon source demand and high energy consumption of high-ammonia-nitrogen and low C / N ratio industrial wastewater.

Description

Technical Field

[0001] This utility model relates to the field of industrial wastewater treatment technology, and more specifically, to an integrated device for MABR membrane modules used in high ammonia nitrogen wastewater treatment. Background Technology

[0002] High ammonia nitrogen industrial wastewater (ammonia nitrogen > 100 mg / L) is commonly found in industries such as printing and dyeing, pharmaceuticals, and coking, and its treatment faces three major technical bottlenecks: (1) High ammonia nitrogen has a biological inhibitory effect on nitrifying bacteria, resulting in low nitrogen removal efficiency of traditional AO process (ammonia nitrogen removal rate <60%). (2) The carbon-to-nitrogen ratio (C / N) is low (generally below 5:1), resulting in insufficient carbon source for the denitrification process and limited total nitrogen removal rate; (3) Traditional aeration processes have low oxygen transfer efficiency (OTE) (only 1530%), resulting in high energy consumption (≥0.8 kWh / m³) and large tank volume, leading to high land costs.

[0003] While existing MABR technology can improve oxygen utilization, its application in treating high ammonia nitrogen industrial wastewater, especially wastewater with a low C / N ratio, is mostly concentrated in the aerobic stage. Directly applying MABR to the anoxic stage, utilizing its unique "reverse diffusion" mechanism for simultaneous nitrification and denitrification, and fully utilizing the carbon source within the wastewater, is an effective way to solve the aforementioned problems. However, existing MABR membrane modules still have shortcomings in terms of long-term stable operation in anoxic environments, anti-clogging, and ease of maintenance; therefore, we propose an integrated MABR membrane module device for high ammonia nitrogen wastewater treatment. Utility Model Content

[0004] The purpose of this invention is to provide a compact and stable integrated device for high ammonia nitrogen wastewater MABR membrane modules, which can achieve simultaneous nitrification and denitrification reactions under anoxic conditions.

[0005] To achieve the above-mentioned objectives, this utility model provides the following technical solution: An integrated MABR membrane module device for high ammonia nitrogen wastewater is proposed to improve the aforementioned problems.

[0006] The application is as follows: An integrated MABR membrane module device for high ammonia nitrogen wastewater includes: The reaction tank is an anoxic biological treatment tank. The membrane module unit is immersed in the reaction tank and includes a membrane frame and several flat hollow fiber membranes fixed on the membrane frame. The aeration system includes a blower, a main air supply pipeline, and an in-membrane aeration pipeline. The blower is connected to the hollow cavity of the flat-plate hollow fiber membrane through the main air supply pipeline and the in-membrane aeration pipeline to provide bubble-free aeration to the membrane. The control system, connected to the blower via a power harness, is used to regulate the gas flow rate and aeration pressure of the aeration system.

[0007] As a preferred technical solution of this application, the flat hollow fiber membrane is made of PVDF, and its filling rate on the membrane frame is 15%.

[0008] As a preferred technical solution of this application, the aeration system also includes a gas flow meter, and the control system adjusts the fan output according to the feedback signal of the gas flow meter to maintain the set air-water ratio.

[0009] As a preferred technical solution of this application, it also includes a flushing pipeline, which is connected in parallel with the main air supply pipeline and is equipped with an independent control valve for periodically air-washing or water-washing the surface of the flat hollow fiber membrane.

[0010] As a preferred technical solution of this application, the membrane module unit is installed in the reaction tank via a liftable bracket.

[0011] As a preferred technical solution of this application, the flat hollow fiber membranes are arranged vertically side by side on the membrane frame.

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows: In the scheme of this application: 1. By forming reverse diffusion oxygen transfer through bubble-free aeration inside the membrane, the nitrification on the membrane surface and the denitrification on the outer layer are realized simultaneously. 2. Integrated flushing pipeline and liftable support effectively reduce membrane fouling and facilitate maintenance; 3. The system has low energy consumption and high carbon source utilization, making it suitable for industrial wastewater with high ammonia nitrogen and low C / N ratio. Attached Figure Description

[0013] Figure 1 This application provides an overall structural schematic diagram of an integrated MABR membrane module device for high ammonia nitrogen wastewater. Figure 2 This application provides a schematic diagram of the piping distribution of an integrated MABR membrane module device for high ammonia nitrogen wastewater.

[0014] The image shows: 1. Reaction tank body; 2. Membrane module unit; 21. Membrane frame; 22. Flat hollow fiber membrane; 3. Aeration system; 31. Blower; 32. Main air supply pipeline; 33. In-membrane aeration pipeline; 34. Gas flow meter; 4. Flushing pipeline; 5. Liftable support; 6. Control system. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model.

[0016] Therefore, the following detailed description of the embodiments of this utility model is not intended to limit the scope of the claimed utility model, but merely illustrates some embodiments of the utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model. It should be noted that, unless otherwise specified, the embodiments, features, and technical solutions in the embodiments of this utility model can be combined with each other.

[0017] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0018] like Figures 1-2 As shown, this embodiment proposes an integrated device for MABR membrane modules used in high ammonia nitrogen wastewater, comprising: Reaction tank 1 is an anoxic biological treatment tank, which contains high ammonia nitrogen wastewater to be treated. Membrane module unit 2 is immersed in the anoxic wastewater in reaction tank 1. Membrane module unit 2 includes membrane frame 21 and several flat hollow fiber membranes 22 fixed on membrane frame 21. The flat hollow fiber membranes 22 are made of PVDF and their filling rate on membrane frame 21 is 15%. The aeration system 3 includes a blower 31, a main air supply pipeline 32, and an in-membrane aeration pipeline 33. The blower 31 is connected to the hollow cavity of the flat hollow fiber membrane 22 through the main air supply pipeline 32 and the in-membrane aeration pipeline 33 to provide bubble-free aeration to the membrane. The aeration system 3 also includes a gas flow meter 34. The control system 6 adjusts the blower output according to the feedback signal of the gas flow meter 34 to maintain the set air-water ratio. The control system 6 is connected to the blower 31 via a power line harness signal and is used to adjust the gas flow rate and aeration pressure of the aeration system 3.

[0019] It also includes a flushing pipeline 4, which is connected in parallel with the main air supply pipeline 32 and is equipped with an independent control valve for periodically washing the surface of the flat hollow fiber membrane 22 with air or water. It can be periodically switched to high-intensity airflow or water flow to periodically flush the biofilm on the membrane surface and control the biofilm thickness to about 200μm.

[0020] The membrane module unit 2 is installed in the reaction tank 1 via a liftable bracket 5, which facilitates its removal from the water surface for maintenance or mechanical cleaning.

[0021] The flat hollow fiber membranes 22 are arranged vertically side by side on the membrane frame 21 with uniform spacing between the membrane sheets to facilitate smooth water flow and uniform growth of the biofilm.

[0022] In use, the anoxic MABR membrane module integrated device operates as follows: First, the membrane module unit 2 is submerged and installed in the anoxic reaction tank 1 via the liftable support 5. Ammonia-resistant nitrifying bacteria are added and the sludge system is activated to maintain the mixed liquor suspended solids concentration at 8 g / L. Subsequently, the aeration system 3 is started, and the blower 31 delivers air to the cavity of the flat hollow fiber membrane 22 through the main air supply pipeline 32 and the membrane aeration pipeline 33. The control system 6 precisely adjusts the air-to-water ratio to 0.05:1, and oxygen diffuses backward through the membrane wall through a bubble-free aeration method, forming a dissolved oxygen microenvironment of 1-2 mg / L on the membrane surface. During steady-state operation, ammonia nitrogen in the wastewater diffuses from the liquid phase to the membrane surface, undergoing nitrification with ammonia-oxidizing and nitrite-oxidizing bacteria enriched on the membrane surface. Simultaneously, organic carbon sources in the wastewater are utilized by denitrifying bacteria in the anoxic zone of the outer biofilm, completing the simultaneous nitrification and denitrification process. During this process, the biofilm gradually forms a stratified structure, with an inner aerobic nitrification zone and an outer anoxic denitrification zone. To maintain stable system operation, the parallel flushing pipeline 4 is periodically activated to control the biofilm thickness to approximately 200 μm through periodic combined air-water flushing, preventing membrane pore blockage and ensuring mass transfer efficiency. Through this process, the device achieved a technological breakthrough by increasing the ammonia nitrogen removal load from 1.2 to ≥2.0 kgN / m³·d under anoxic conditions. Simultaneously, by utilizing an endogenous carbon source, the system's carbon-to-nitrogen ratio requirement was reduced from 8:1 to 5:1, and aeration energy consumption was reduced by more than 70% compared to traditional processes. Ultimately, the effluent ammonia nitrogen concentration was stably controlled below 15 mg / L. The entire operation process utilizes an integrated control system 6 to achieve real-time parameter monitoring and precise control, ensuring the efficient and stable operation of the device in the treatment of high-ammonia-nitrogen wastewater.

[0023] The above embodiments are only used to illustrate the present utility model and are not intended to limit the technical solutions described in the present utility model. Although the present utility model has been described in detail with reference to the above embodiments, the present utility model is not limited to the specific embodiments described above. Therefore, any modifications or equivalent substitutions to the present utility model, and all technical solutions and improvements that do not depart from the spirit and scope of the utility model, are covered within the scope of the claims of the present utility model.

Claims

1. An integrated device for MABR membrane modules used in high ammonia nitrogen wastewater, characterized in that, include: The reaction tank (1) is an anoxic biological treatment tank; The membrane module unit (2) is immersed in the reaction tank (1). The membrane module unit (2) includes a membrane frame (21) and a plurality of flat hollow fiber membranes (22) fixed on the membrane frame (21). The aeration system (3) includes a blower (31), a main air supply pipeline (32) and an in-membrane aeration pipeline (33). The blower (31) is connected to the hollow cavity of the flat hollow fiber membrane (22) through the main air supply pipeline (32) and the in-membrane aeration pipeline (33) to provide bubble-free aeration to the membrane. The control system (6) is connected to the blower (31) via a power line harness signal and is used to adjust the gas flow rate and aeration pressure of the aeration system (3).

2. The MABR membrane module integration device for high ammonia nitrogen wastewater according to claim 1, characterized in that, The flat hollow fiber membrane (22) is made of PVDF and has a filling rate of 15% on the membrane frame (21).

3. The MABR membrane module integration device for high ammonia nitrogen wastewater according to claim 1, characterized in that, The aeration system (3) also includes a gas flow meter (34), and the control system (6) adjusts the fan output according to the feedback signal of the gas flow meter (34) to maintain the set air-water ratio.

4. The MABR membrane module integration device for high ammonia nitrogen wastewater according to claim 1, characterized in that, It also includes a flushing pipeline (4), which is connected in parallel with the main air supply pipeline (32) and is equipped with an independent control valve for periodically air washing or water washing of the surface of the flat hollow fiber membrane (22).

5. The MABR membrane module integration device for high ammonia nitrogen wastewater according to claim 1, characterized in that, The membrane module unit (2) is installed in the reaction tank body (1) via a liftable bracket (5).

6. The MABR membrane module integration device for high ammonia nitrogen wastewater according to claim 1, characterized in that, The flat hollow fiber membrane (22) is arranged vertically side by side on the membrane frame (21).

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