Device and method for treating electron-poor sewage by strengthening iron-carbon mud membrane based on bubble-free aeration

Abstract

A device and method for treating electron-poor sewage enhanced by iron-carbon sludge membrane based on bubble-free aeration belongs to the technical field of sewage treatment. The present invention solves the problems that the existing membrane oxygen transfer biofilm technology cannot adapt to low carbon-nitrogen ratio sewage, the electron donors generated by the carbon source in the denitrification process are insufficient, and the operating cost of the external carbon source is high. A porous partition plate is vertically fixed in the reactor body, and the inside of the reactor body is divided into an iron-carbon filling chamber and a bubble-free aeration chamber on the left and right by the porous partition plate. The MABR membrane assembly is fixed in the bubble-free aeration chamber and connected to the gas cylinder through an air supply pipeline. An iron-carbon micro-electrolysis filler is arranged in the iron-carbon filling chamber. The water inlet tank is connected to the water inlet of the reactor body through the water inlet pipeline, and the water outlet tank is connected to the water outlet of the reactor body through the water outlet pipeline. The sewage is coupled with the microbial metabolic process of the biofilm attached to the surface of the MABR membrane assembly through the iron-carbon sludge micro-electrolysis process to synergistically remove pollutants in the water.

Description

Technical Field

[0001] The invention relates to a device and method for treating electron-poor sewage by strengthening an iron-carbon mud membrane based on bubble-free aeration, and belongs to the technical field of sewage treatment. Background Art

[0002] Most of the existing domestic sewage has the problem of insufficient carbon source. The electron donors required for denitrification are insufficient, resulting in the need to add external carbon sources for conventional activated sludge denitrification. On the one hand, this increases costs, and on the other hand, the external carbon source will also increase sludge production and increase the burden of subsequent sludge treatment.

[0003] Iron-carbon micro-electrolysis uses the corrosion reaction of the iron anode to produce Fe 2+ , enriching nitrate-reducing ferrous iron oxidizing bacteria (NRFOB), which transfers oxidized Fe 2+ After the electrons are transferred to ubiquinone, Nar on the cell membrane reduces nitrate nitrogen by accepting electrons from ubiquinone, reducing the demand for additional organic matter in the treatment of electron-poor wastewater. In addition, the iron coagulation produced during the electron supply process can also improve the removal of phosphate in wastewater. However, iron corrosion and Fe 2+ The oxidation process requires the participation of oxygen. The oxygen utilization rate of aeration methods such as forced aeration used in existing iron-carbon micro-electrolysis technology is not high, and the energy consumption of traditional forced aeration accounts for 50-70% of the energy consumption of sewage treatment plants, resulting in high energy consumption. At the same time, in the field of water treatment, hydraulic disturbances do not cause great damage to the system, but the shear force generated by the action of air and water is huge, so traditional forced aeration will inevitably cause greater disturbances in the system, and it is also easy to shear the mud film formed on the surface of iron-carbon, and then it is easy to cause the iron mud formed by the oxidized iron to fall off, which ultimately leads to a longer start-up time for the reactor; in addition, ordinary aeration will cause the dissolved oxygen in the reactor to reach 6-7 mg / L, causing a large amount of ineffective oxidation loss of the exposed iron, and the large amount of iron loss will cause a large amount of iron hydroxide (iron mud) to be produced, blocking the reaction tank.

[0004] In addition, in the prior art, sewage treatment equipment using iron-carbon micro-electrolysis technology mostly has iron-carbon piled at the bottom or top of the equipment. After the equipment has been running for a certain period of time, iron-carbon needs to be replenished into the equipment. When the iron-carbon is located at the bottom of the equipment, the sewage in the equipment will inevitably be disturbed to a large extent during the replenishment process. If there are other structures above the iron-carbon, the structure needs to be moved before the iron-carbon can be replenished, resulting in a more cumbersome process of replenishing the iron-carbon. When the iron-carbon is located at the top of the equipment, it will hinder other structures below the iron-carbon, which is not conducive to equipment maintenance. Summary of the invention

[0005] The present invention aims to solve the problems that the existing membrane oxygen transfer biofilm technology cannot adapt to low carbon-nitrogen ratio sewage, the electron donors generated by the carbon source in the denitrification process are insufficient, and the operating cost of the external carbon source is high, and further provides an iron-carbon mud membrane-enhanced electron-poor sewage treatment device and method based on bubble-free aeration.

[0006] The technical solution adopted by the present invention to solve the above technical problems is:

[0007] A device for treating electron-poor sewage enhanced by iron-carbon mud membrane based on bubble-free aeration comprises a reactor body, an inlet water tank, an outlet water tank, a gas cylinder and a MABR membrane assembly, wherein a porous partition plate is vertically fixed in the reactor body, and the interior of the reactor body is divided into an iron-carbon filling chamber and a bubble-free aeration chamber on the left and right sides by the porous partition plate; the MABR membrane assembly is fixed in the bubble-free aeration chamber and connected to the gas cylinder through an air supply pipeline; an iron-carbon micro-electrolysis filler is arranged in the iron-carbon filling chamber; the inlet water tank is connected to the water inlet of the reactor body through the inlet water tank, and the outlet water tank is connected to the water outlet of the reactor body through the outlet water tank.

[0008] Furthermore, there are multiple MABR membrane modules, which are fixed side by side in the horizontal direction on a side wall of the reactor body.

[0009] Furthermore, the MABR membrane assembly adopts a hydrophobic organic membrane.

[0010] Furthermore, the top cover of the reactor body is provided with a top cover.

[0011] Furthermore, an air intake valve, a pressure gauge and a gas flow meter are provided on the air supply pipeline.

[0012] Furthermore, a water inlet valve, a water inlet pump and a water inlet flow meter are arranged on the water inlet pipeline, and a water outlet valve is arranged on the water outlet pipeline.

[0013] Furthermore, the water inlet and the water outlet of the reactor body are respectively arranged on the front and rear side walls of the reactor body, and the water inlet is arranged lower than the water outlet.

[0014] Furthermore, the diameter of the water outlet is set to be greater than or equal to the diameter of the water inlet.

[0015] A sewage treatment method using the above device comprises the following steps:

[0016] Step 1: The raw water in the water inlet tank enters the reactor body through the water inlet pipeline, and the water inlet volume is controlled so that the ratio of the effective volume in the reactor body to the water inlet volume is the set hydraulic retention time;

[0017] Step 2: The gas cylinder performs bubble-free aeration into the reactor body through the gas supply pipeline and the membrane assembly;

[0018] Step 3: The sewage in the reactor body is coupled with the iron-carbon sludge micro-electrolysis process in the iron-carbon filling chamber and the microbial metabolism process of the biofilm attached to the surface of the MABR membrane assembly to synergistically remove pollutants in the water;

[0019] Step 4: The sewage in the reactor body is discharged into the outlet water tank through the outlet pipe.

[0020] Furthermore, the hydraulic retention time set in step 1 is 8 to 48 hours.

[0021] Compared with the prior art, the present invention has the following effects:

[0022] The sewage in the reactor body is coupled with the iron-carbon sludge micro-electrolysis process in the iron-carbon filling chamber and the microbial metabolic process of the biofilm attached to the surface of the MABR membrane assembly to synergistically remove pollutants in the water. Compared with the existing technology, it effectively improves the treatment effect of domestic sewage and proposes a simple, effective and low-energy treatment strategy to solve the problem of denitrification of electron-lean sewage.

[0023] The present invention couples iron-carbon sludge and bubble-free aerated biofilm. On the one hand, bubble-free aeration is used to improve gas supply efficiency, avoiding the problem of high oxygen concentration in the mixed liquid caused by ordinary oxygen supply methods, which in turn causes iron loss due to rapid oxidation of iron. Secondly, iron-carbon micro-electrolysis is used to supply electrons to reduce the dependence of the denitrification process on organic matter. Finally, the iron coagulation generated in the electron supply process can efficiently remove phosphorus. Compared with the prior art, the iron-carbon sludge membrane-based bubble-free aeration enhanced electron-poor sewage treatment device of the present invention has better effluent quality, is less affected by organic carbon concentration, has less oxygen supply, occupies a smaller area, has lower operating costs, is simpler to operate and manage, has less maintenance workload, and has lower requirements on the operating technical level of workers.

[0024] The present invention adopts bubble-free aeration technology to diffuse the oxygen in the membrane cavity into the mixed liquid through the membrane pores. The efficient oxygen mass transfer improves the oxygen utilization efficiency and avoids the problems of high oxygen concentration in the mixed liquid and iron loss caused by large-scale oxidation of iron caused by ordinary oxygen supply methods.

[0025] In the present invention, by adopting MABR membrane components, the biological process can achieve true bubble-free aeration of membrane aeration. The gas diffuses out from the membrane pores and is quickly utilized by the organisms attached to the surface of the aeration membrane before visible bubbles are formed, thereby forming bubble-free aeration and effectively preventing the iron sludge formed by oxidized iron from falling off.

[0026] In the present invention, the gas enters the reactor body through the biofilm in the MABR membrane assembly and does not come into direct contact with the iron and carbon, thereby further avoiding a large loss of iron and carbon.

[0027] An iron-carbon filling chamber is provided in the reactor body 1, and the problem of insufficient carbon source of low carbon-nitrogen ratio sewage is alleviated by adding iron-carbon micro-electrolysis filler 10;

[0028] The iron-carbon micro-electrolysis filler 10 of the present invention has a longer service life and only needs to be added once during the startup phase of the device to maintain efficient operation of the device. The operation is simple and the operating cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a front view schematic diagram of the present invention.

[0030] In the figure: 1. Reactor body; 1-1. Water inlet; 1-2. Water outlet; 2. Water inlet tank; 3. Water outlet tank; 4. Gas cylinder; 5. MABR membrane assembly; 6. Porous partition plate; 9. Gas supply pipeline; 10. Iron-carbon micro-electrolysis filler; 11. Water inlet pipeline; 12. Water outlet pipeline; 13. Top cover; 14. Air inlet valve; 15. Pressure gauge; 16. Gas flow meter; 17. Water inlet valve; 18. Water inlet pump; 19. Water inlet flow meter; 20. Water outlet valve. DETAILED DESCRIPTION

[0031] Specific implementation method 1: Combination Figure 1 This embodiment is explained, and the technical scheme in the embodiment of the present invention is clearly and completely described. Obviously, the described embodiment is only a part of the embodiment of the present invention, rather than all the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0032] It should be noted that the descriptions of the present invention regarding directions such as "front", "back", "left", "right", "inside", "outside", "left side", "right side", "upper", "lower", "top", "bottom", etc. are all defined based on the relationship between the orientations or positions shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the structure must be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention. In the description of the present invention, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0033] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] A device for treating electron-poor sewage by strengthening iron-carbon mud membrane based on bubble-free aeration comprises a reactor body 1, an inlet tank 2, an outlet tank 3, a gas cylinder 4 and an MABR membrane assembly 5, wherein a porous partition plate 6 is vertically fixed in the reactor body 1, and the inside of the reactor body 1 is divided into an iron-carbon filling chamber and a bubble-free aeration chamber on the left and right sides by the porous partition plate 6; the MABR membrane assembly 5 is fixed in the bubble-free aeration chamber and connected to the gas cylinder 4 through an air supply pipeline 9; an iron-carbon micro-electrolysis filler 10 is arranged in the iron-carbon filling chamber; the inlet tank 2 is connected to the water inlet 1-1 of the reactor body 1 through an inlet pipeline 11; and the outlet tank 3 is connected to the water outlet 1-2 of the reactor body 1 through an outlet pipeline 12.

[0035] The reactor body 1 is provided with a water inlet 1 - 1 and a water outlet 1 - 2 , which are used for water inlet and water outlet of the reactor body 1 , respectively.

[0036] The porous partition plate 6 is, for example, a wire mesh, a porous plate or the like.

[0037] The MABR membrane assembly 5 (MABR, i.e., membrane aerated biofilm reactor) is a detachable structure. The MABR membrane assembly 5 is connected to the gas cylinder 4 to perform bubble-free aeration inside the reactor body 1. The MABR membrane assembly 5 is provided with an air inlet, and an air supply line 9 connects the gas cylinder 4 and the air inlet of the MABR membrane assembly 5.

[0038] The reactor body 1 is a square box structure made of organic glass.

[0039] The sewage in the reactor body 1 is coupled with the iron-carbon sludge micro-electrolysis process in the iron-carbon filling chamber and the microbial metabolism process of the biofilm attached to the surface of the MABR membrane assembly 5 to synergistically remove pollutants in the water. Compared with the existing technology, it effectively improves the treatment effect of domestic sewage and proposes a simple, effective and low-energy treatment strategy to solve the problem of denitrification of electron-poor sewage.

[0040] The present invention adopts bubble-free aeration technology to diffuse the oxygen in the membrane cavity into the mixed liquid through the membrane pores. The efficient oxygen mass transfer improves the oxygen utilization efficiency and avoids the problems of high oxygen concentration in the mixed liquid and iron loss caused by large-scale oxidation of iron caused by ordinary oxygen supply methods.

[0041] In the present invention, by adopting the MABR membrane module 5, the biological process can realize the true bubble-free aeration of membrane aeration, the gas diffuses out from the membrane pores, and is quickly utilized by the organisms attached to the surface of the aeration membrane before the bubbles visible to the naked eye are formed, thereby forming bubble-free aeration, effectively preventing the iron mud formed by the oxidized iron from falling off. If there is no such layer of organisms, the diffused gas will gather into bubbles to form gas-water purge, which will eventually lead to greater disturbance in the system, and it is also easy to shear the mud film formed on the iron-carbon surface, thereby making it easy for the iron mud formed by the oxidized iron to fall off.

[0042] In the present invention, the gas enters the reactor body 1 through the biofilm in the MABR membrane assembly 5 and does not come into direct contact with the iron and carbon, thereby further avoiding a large loss of iron and carbon.

[0043] Under membrane aeration, the disturbance in the reactor body 1 is small, the iron sludge formed by the oxidized iron is not easy to fall off, the organisms are effectively captured, the film is quickly formed on the iron-carbon surface, and the reactor startup time is shortened;

[0044] Iron-carbon and organisms form a mud film system. Through bubble-free aeration, the mud film formed on the surface of iron-carbon will not be sheared to cause the mud film to fall off, effectively avoiding the exposure of iron-carbon.

[0045] The membrane aeration system is in an oxygen-deficient state, and the dissolved oxygen in the mixed liquid in contact with iron and carbon is around 1 mg / L, forming the characteristic of slow release of iron.

[0046] The iron-carbon filler is placed on one side of the membrane assembly, and the two do not interfere with each other, thus avoiding damage to the membrane assembly during replacement or addition of the iron-carbon filler;

[0047] Under membrane aeration, iron and carbon form a part of the coagulation and capture effect, which captures phosphate to the surface of the iron-carbon mud membrane, strengthens phosphorus removal, and makes up for the poor phosphorus removal efficiency of the existing membrane aeration biofilm reactor;

[0048] The iron-carbon biofilm system will form a large number of bacteria that use micro-electrolysis electrons for denitrification and complete the autotrophic denitrification process with less carbon source supply.

[0049] In the iron-carbon mud membrane-enhanced electron-poor sewage treatment device based on bubble-free aeration of the present invention, an iron-carbon filling chamber is arranged in the reactor body 1, and the problem of insufficient carbon source of low carbon-nitrogen ratio sewage is alleviated by adding iron-carbon micro-electrolysis filler 10. The iron-carbon filler forms countless tiny corrosion cells in the sewage, and the Fe generated by the corrosion reaction of the iron anode is used. 2+ , enriching nitrate-reducing ferrous iron oxidizing bacteria (NRFOB), thereby promoting the reduction of nitrate nitrogen. 2+ The addition of additional electron donors also increased the activity of nitric oxide reductase NorB and NosZ, promoting the further reduction of denitrification intermediate NO to N2, thereby promoting the removal of total nitrogen and reducing the influence of organic matter on the denitrification process.

[0050] In addition, by setting up an iron-carbon filling chamber, the Fe 2+ The iron coagulation produced by oxidation during the electron donation process can further improve the removal effect of phosphate in wastewater.

[0051] By setting up an iron-carbon filling chamber, the iron-carbon micro-electrolysis filling 10 anode Fe 2+ The oxidation product FeOOH can enrich ferric iron reducing bacteria (FRB).3+ The degradation of organic matter can be improved in the process, and Fe 2+ and Fe 3+ Therefore, the iron-carbon micro-electrolysis filler 10 of the present invention has a longer service life, and only needs to be added once during the startup phase of the device to maintain the efficient operation of the device, which is simple to operate and has low operating costs.

[0052] In the iron-carbon mud membrane enhanced electron-poor sewage treatment device based on bubbleless aeration of the present invention, bubbleless aeration is adopted. Compared with traditional aeration heads or blower aeration, the oxygen transfer rate is higher, energy consumption is more saved, and the stripping of volatile pollutants or greenhouse gases caused by bubble aeration is avoided, thereby reducing pollution to the atmosphere.

[0053] The iron-carbon mud membrane-enhanced electron-poor sewage treatment device based on bubble-free aeration of the present invention adopts a detachable MABR membrane component 5, and the number and size of the membrane components can be adjusted according to different influent water qualities, thereby expanding the adaptability of the membrane oxygen transfer biofilm reactor to sewage with different carbon-nitrogen ratios.

[0054] The present invention couples iron-carbon sludge and bubble-free aerated biofilm. On the one hand, bubble-free aeration is used to improve gas supply efficiency, avoiding the problem of high oxygen concentration in the mixed liquid caused by ordinary oxygen supply methods, which in turn causes iron loss due to rapid oxidation of iron. Secondly, iron-carbon micro-electrolysis is used to supply electrons to reduce the dependence of the denitrification process on organic matter. Finally, the iron coagulation generated in the electron supply process can efficiently remove phosphorus. Compared with the prior art, the iron-carbon sludge membrane-based bubble-free aeration enhanced electron-poor sewage treatment device of the present invention has better effluent quality, is less affected by organic carbon concentration, has less oxygen supply, occupies a smaller area, has lower operating costs, is simpler to operate and manage, has less maintenance workload, and has lower requirements on the operating technical level of workers.

[0055] The number of the MABR membrane components 5 is multiple, and they are fixedly mounted side by side in the horizontal direction on one side wall of the reactor body 1. In this design, the number of MABR membrane components 5 is related to the volume of the reactor body 1. The larger the volume of the reactor body 1, the more MABR membrane components 5 are installed. The MABR membrane components 5 use a hydrophobic organic membrane, not limited to an inorganic membrane such as a ceramic membrane.

[0056] The MABR membrane assembly 5 adopts a hydrophobic organic membrane. The membrane material is polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polypropylene (PP) or polydimethylsiloxane (PDMS), and the membrane pore size is 0.01m~0.20μm; the number and size of the membrane assembly can be changed, and the effective area of ​​the membrane is 0.01~0.04m 2 .

[0057] The top cover of the reactor body 1 is provided with a top cover 13 .

[0058] The gas supply pipeline 9 is provided with an air intake valve 14 , a pressure gauge 15 and a gas flow meter 16 .

[0059] The water inlet pipe 11 is provided with a water inlet valve 17, a water inlet pump 18 and a water inlet flow meter 19, and the water outlet pipe 12 is provided with a water outlet valve 20. With such a design, the oxygen supply mode can be designed to be continuous oxygen supply or intermittent oxygen supply according to the water quality of the outlet water.

[0060] The water inlet 1-1 and the water outlet 1-2 of the reactor body 1 are respectively arranged on the front and rear side walls of the reactor body 1, and the water inlet 1-1 is arranged lower than the water outlet 1-2.

[0061] The diameter of the water outlet 1-2 is set to be greater than or equal to the diameter of the water inlet 1-1.

[0062] A sewage treatment method using the above device comprises the following steps:

[0063] Step 1: The raw water in the water inlet tank 2 enters the reactor body 1 through the water inlet pipe 11. By controlling the water inlet amount, the ratio of the effective volume in the reactor body 1 to the water inlet amount is made to be the set hydraulic retention time; the raw water in the water inlet tank 2 enters the reactor body 1 through the water inlet pipe 11 under the lifting of the water inlet pump 18.

[0064] Step 2: The gas cylinder 4 performs bubble-free aeration into the reactor body 1 through the gas supply pipeline 9 and the membrane assembly; the aeration pressure is controlled at 10-300 kPa and the gas flow rate is controlled at 1-5 mL / min by adjusting the air inlet valve 14, the pressure gauge 15 and the gas flow meter 16, so that no bubbles visible to the naked eye appear on the surface of the membrane assembly. The gas supply mode can be continuous gas supply or intermittent gas supply, and the gas supply type can be air or pure oxygen.

[0065] Step 3: The sewage in the reactor body 1 is coupled with the iron-carbon sludge micro-electrolysis process in the iron-carbon filling chamber and the microbial metabolism process of the biofilm attached to the surface of the MABR membrane assembly 5 to synergistically remove pollutants in the water; because the oxygen supply is bubble-free aeration, in order to make the system completely mixed, dynamic stirring is used, and the speed of the stirrer used is 20-1000rpm. The dosage of the iron-carbon micro-electrolysis filler 10 in the iron-carbon filling chamber is 0-300g / L, the particle size of the iron-carbon micro-electrolysis filler 10 is spherical 3-14mm, and the specific surface area is 0.8-1.6m 2 / g.

[0066] Step 4: The sewage in the reactor body 1 is discharged into the outlet water tank 3 through the outlet pipe 12. The sewage flows upward from the bottom of the reactor body 1 and overflows into the outlet pipe 12 through the outlet 1-2.

[0067] The hydraulic retention time set in step 1 is 8 to 48 hours.

[0068] Specific implementation method 2: Combination Figure 1 To illustrate this embodiment, a sewage treatment method using the device described in the above specific embodiment 1 includes the following steps:

[0069] Step 1: Biofilm formation in the reactor. Add 4000 mg / L of sludge from the secondary sedimentation tank to the reactor body 1, and at the same time add 50 g of carbon with a specific surface area of ​​1.2 m2 to the iron-carbon filling chamber in the reactor body 1. 2 / g, spherical iron-carbon filler with a particle size of 3 to 6 mm. In the startup phase, the reactor body 1 operates in SBR (sequencing batch reactor) mode at room temperature, with a cycle of 12 hours, including 20 minutes of water inlet, 11 hours of mixed aeration, and 40 minutes of sedimentation and drainage. The raw water is lifted by the water inlet pump 18 and enters the reactor body 1 through the water inlet pipeline 11. The air inlet valve 14 on the air supply pipeline 9 is opened to supply oxygen to the MABR membrane assembly 5, and the aeration volume is controlled at 2mL / min. The raw water is artificial synthetic wastewater, in which COD is 300mg / L, ammonia nitrogen is 40mg / L, and phosphate is 3mg / L. Effluent water samples are collected daily and water quality analysis is performed regularly. After 1 to 2 weeks, when the iron-carbon surface in the iron-carbon filling chamber is covered with brown sludge, and the microporous membrane surface on the MABR membrane assembly 5 is tightly attached to the biofilm, the reactor is deemed to have successfully formed a biofilm.

[0070] Step 2, stable operation stage. In the stable operation stage, the reactor body 1 operates in a continuous flow mode at room temperature. The experiment sets three stages, with carbon-nitrogen ratios of 2, 5, and 8, respectively. The hydraulic retention time is set to 24h and the stirring speed is 500rpm. The raw water in the inlet tank 2 enters the reactor body 1 through the inlet pipe 11 under the lifting of the inlet pump 18. The inlet volume is adjusted by controlling the inlet pump 18 so that the ratio of the effective volume of the reactor body 1 to the inlet volume is 24h. The gas is supplied by the gas cylinder 4 and enters the MABR membrane assembly 5 through the gas supply pipe 9 to aerate the reactor body 1; the gas flow rate is controlled at 2mL / min by adjusting the inlet valve 14, the pressure gauge 15 and the gas flow meter 16, so that no bubbles visible to the naked eye appear on the surface of the MABR membrane assembly 5; the dissolved oxygen concentration in the reactor body 1 is controlled to be below 0.5mg / L. The sewage in the reactor body 1 is coupled with the microbial process in the biofilm attached to the surface of the membrane assembly through the iron-carbon micro-electrolysis process in the iron-carbon filling chamber to achieve the removal of pollutants in the water. The sewage flows upward from the bottom of the reactor body 1 , overflows through the outlet 1 - 2 into the outlet pipe 12 , and then flows into the outlet tank 3 .

[0071] The effluent samples collected regularly were measured, and the removal rates of COD, TN and TP were calculated. The results are shown in Table 1. Compared with the single bubbleless aeration device, the Fe / C-MABR reactor of the present invention has a significant effect, and the removal rate of total nitrogen can reach up to 90.74%. The ammonia nitrogen removal efficiency is slightly improved compared with the conventional MABR, and the total nitrogen and phosphate effects are significantly improved.

[0072] The results of the sewage inlet and outlet quality of this experiment are shown in Table 1.

[0073]

[0074] Table 1

[0075] As can be seen from Table 1, the sewage treatment device and method of the present invention have ideal pollution removal effect. Compared with the traditional MABR, the bubble-free aerated iron-carbon mud membrane system of the present application has good stability, which provides a reference for the effective removal of total nitrogen and phosphate in electron-lean sewage.

[0076] Other components and connection relationships are the same as those in the first specific implementation mode.

[0077] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A sewage treatment method, characterized in that: The invention discloses an iron-carbon mud membrane enhanced electron-poor sewage treatment device based on bubble-free aeration, the device comprising a reactor body (1), an inlet water tank (2), an outlet water tank (3), a gas cylinder (4) and an MABR membrane assembly (5), wherein a porous partition plate (6) is vertically fixed in the reactor body (1), and the inside of the reactor body (1) is divided into an iron-carbon filling chamber and a bubble-free aeration chamber on the left and right sides by the porous partition plate (6); the MABR membrane assembly (5) is fixed in the bubble-free aeration chamber and connected to the gas cylinder (4) through an air supply pipeline (9); an iron-carbon micro-electrolysis filler (10) is arranged in the iron-carbon filling chamber; the inlet water tank (2) is connected to the water inlet (1-1) of the reactor body (1) through an inlet water tank (11); and the outlet water tank (3) is connected to the water outlet (1-2) of the reactor body (1) through an outlet water tank (12); the MABR membrane assembly (5) is a detachable structure; The MABR membrane modules (5) are multiple in number and are fixedly mounted side by side on a side wall of the reactor body (1) in a horizontal direction; The sewage treatment method includes a reactor biofilm formation stage and a stable operation stage, wherein: The reactor biofilm formation stage comprises the following steps: Secondary sedimentation tank sludge is added to the reactor body (1), and spherical iron-carbon fillers are added to the iron-carbon filling chamber in the reactor body (1); during the startup phase, the reactor body (1) operates in SBR mode at room temperature, with a cycle of 12 hours, including 20 minutes of water intake, 11 hours of mixed aeration, and 40 minutes of sedimentation and drainage; raw water enters the reactor body (1), and oxygen is supplied to the MABR membrane assembly (5) through the air supply pipeline (9); effluent water samples are collected daily, and water quality analysis is performed regularly; after 1 to 2 weeks, when the iron-carbon surface in the iron-carbon filling chamber is covered with brown sludge, and a dense biofilm is attached to the microporous membrane surface of the MABR membrane assembly (5), it is determined that the reactor biofilm is successfully formed; The stable operation stage includes the following steps: Step 1: Raw water in the water inlet tank (2) enters the reactor body (1) through the water inlet pipeline (11), and the water inlet volume is controlled so that the ratio of the effective volume in the reactor body (1) to the water inlet volume is equal to the set hydraulic retention time; Step 2: The gas cylinder (4) performs bubble-free aeration into the reactor body (1) through the gas supply pipeline (9) and the membrane assembly; Step 3: The sewage in the reactor body (1) is coupled with the iron-carbon sludge micro-electrolysis process in the iron-carbon filling chamber and the microbial metabolism process of the biofilm attached to the surface of the MABR membrane assembly (5) to synergistically remove pollutants in the water; Step 4: The sewage in the reactor body (1) is discharged into the outlet water tank (3) through the outlet water pipeline (12).

2. The sewage treatment method according to claim 1, characterized in that: The MABR membrane assembly (5) adopts a hydrophobic organic membrane.

3. The sewage treatment method according to claim 1, characterized in that: The top cover of the reactor body (1) is provided with a top cover (13).

4. The sewage treatment method according to claim 1, characterized in that: An air inlet valve (14), a pressure gauge (15) and a gas flow meter (16) are provided on the air supply pipeline (9).

5. The sewage treatment method according to claim 1, characterized in that: The water inlet pipeline (11) is provided with a water inlet valve (17), a water inlet pump (18) and a water inlet flow meter (19), and the water outlet pipeline (12) is provided with a water outlet valve (20).

6. The sewage treatment method according to claim 1, characterized in that: The water inlet (1-1) and the water outlet (1-2) of the reactor body (1) are respectively arranged on the front and rear side walls of the reactor body (1), and the water inlet (1-1) is arranged lower than the water outlet (1-2).

7. The sewage treatment method according to claim 1 or 6, characterized in that: The diameter of the water outlet (1-2) is set to be greater than or equal to the diameter of the water inlet (1-1).

8. The sewage treatment method according to claim 1, characterized in that: The hydraulic retention time set in step 1 is 8 to 48 hours.

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