MABR-based railway domestic sewage treatment system and use method thereof

Abstract

The invention discloses an MABR-based railway domestic sewage treatment system and a use method thereof, and relates to the technical field of sewage treatment, the MABR-based railway domestic sewage treatment system mainly comprises a water inlet unit, an anaerobic zone, an anoxic MABR zone, a transition MABR zone, an aerobic MABR filler zone, a sedimentation tank, a filter unit and a clear water output unit which are connected in sequence, and also comprises a sludge external reflux system and a gas supply system; according to the present invention, the respective advantages of the MABR technology and the water treatment filler are fully utilized, the simultaneous nitrification and denitrification are performed to efficiently remove the pollutants, the denitrification is well achieved by using the transition MABR region, and the pollutants are further removed by using the filtration unit, such that the domestic sewage treatment problem of the staff along the railway line is effectively solved, and the high efficiency, the stability and the sustainability of the sewage treatment are achieved. The method has the advantages of high pollutant removal efficiency, no internal reflux of mixed liquid, reduction of sludge yield, energy conservation, carbon reduction, easiness in operation and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of sewage treatment, and particularly relates to a MABR-based railway domestic sewage treatment system and its usage method. Background Art

[0003] As a new sewage treatment technology - MABR technology, it has been widely used in surface water bodies, improving the quality and efficiency of urban sewage treatment, and rural sewage treatment in recent years. The MABR technology combines the traditional biofilm method and membrane separation technology, and provides oxygen for the biofilm through the aeration of the membrane, enabling the biofilm to achieve efficient sewage treatment with low energy consumption. The MABR system has the advantages of small floor area, stable operation, strong shock load resistance, simple maintenance and management, low energy consumption, etc., and is very suitable for treating decentralized and difficult-to-treat domestic sewage.

[0004] In view of this, the present invention aims to provide a MABR-based railway domestic sewage treatment system and method, which uses MABR technology to establish a biological treatment unit jointly with MABR and fillers, and at the same time sets up a filtration unit to form a coupled sewage treatment technology system and usage method, effectively solving the problem of domestic sewage treatment for railway employees along the line, and realizing the high efficiency, stability and sustainability of sewage treatment. Summary of the Invention

[0005] In summary, the present invention provides a MABR-based railway domestic sewage treatment system and method, including an inlet unit, an anaerobic reaction zone, an anoxic MABR zone, a transition MABR zone, an aerobic MABR filler zone, a sedimentation tank, a filtration unit and a clean water output unit connected in sequence. By constructing a MABR sludge membrane treatment system, using MABR technology in combination with the activated sludge method to degrade pollutants, and making full use of the efficient denitrification technology of MABR, a transition MABR zone is set to better meet the efficient removal of pollutants in the MABR area, realizing the efficient and energy-saving treatment of railway domestic sewage.

[0006] A MABR-based railway domestic sewage treatment system, characterized in that: it includes an inlet unit, an anaerobic zone, an anoxic MABR zone, a transition MABR zone, an aerobic MABR filler zone, a sedimentation tank, a filtration unit and a clean water output unit connected in sequence, and also includes a sludge external reflux system and a gas supply system; The anoxic MABR zone and the transition MABR zone are mainly composed of MABR membrane boxes; The aerobic MABR packing zone includes an MABR membrane treatment zone and a biological packing zone. The MABR membrane treatment zone is arranged at the front end of the biological packing zone. MABR membrane boxes are implanted in the MABR membrane treatment zone, and curtain-type water treatment packing units are implanted in the biological packing zone. The volume of the area where the MABR membrane boxes are located accounts for no more than 1 / 3 of the volume of the MABR packing zone. In the sludge external reflux system, the reflux ratio is set to 50%-100%. Among them, 0%-50% is refluxed to the anaerobic zone, and 50%-100% is refluxed to the anoxic MABR zone. The air supply system is mainly composed of an air supply device, an air supply pipeline, and a control valve. The air supply system supplies air to the anoxic MABR zone, the transitional MABR zone, and the aerobic MABR packing zone respectively, and the air supply volume and air supply pressure are adjusted through the control valve.

[0007] The method for using the MABR railway domestic sewage treatment system according to claim 1 is characterized in that it includes the following steps: (1) Construction of the sewage treatment system: Connect the anaerobic zone, the anoxic MABR zone, the transitional MABR zone, the aerobic MABR packing zone, and the sedimentation tank in sequence. MABR membrane boxes and curtain-type water treatment packing units are implanted in the anoxic MABR zone, the transitional MABR zone, and the aerobic MABR packing zone respectively. An overpass connecting pipe is provided between the aerobic MABR packing zone and the sedimentation tank, and the MABR packing zone and the sedimentation tank are directly connected through the overpass filtering unit and the clear water output unit. Start the air supply system to supply air to the anoxic MABR zone, the transitional MABR zone, and the aerobic MABR packing zone. (2) System film hanging and domestication: Domestic sewage and activated sludge are put into the anaerobic zone, the anoxic MABR zone, the transitional MABR zone, and the aerobic MABR packing zone from the water inlet unit. The anoxic MABR zone, the transitional MABR zone, and the aerobic MABR packing zone are aerated statically for 24 hours and then fed intermittently. The film hanging and domestication period is 5-7 days. (3) System commissioning and start-up: Close the overpass connecting pipe provided between the aerobic MABR packing zone and the sedimentation tank, and continuously feed water from the water inlet unit. The total hydraulic retention time of the anaerobic zone, the anoxic MABR zone, the transitional MABR zone, and the aerobic MABR packing zone is gradually reduced from 48 hours to 24 hours, with each reduction of 2 hours and each cycle running for 3-5 days. Regularly detect the water quality of the influent and effluent. (4) System operation: Connect the filtration unit, clean water output unit, and sludge external reflux system into step (3). The influent unit continuously feeds water. The total hydraulic retention time in the anaerobic zone, anoxic MABR zone, transition MABR zone, and aerobic MABR packing zone is maintained at 16 - 24 h and adjusted according to the treatment requirements. The air supply system supplies air to the anoxic MABR zone, transition MABR zone, and aerobic MABR packing zone, monitors the DO concentration in the pool bodies of each zone, and adjusts the air supply pressure and air supply flow of each zone through valves. The sludge external reflux system controls the sludge reflux ratio in the anaerobic zone and anoxic MABR zone respectively; monitor the water quality of the influent unit and clean water output unit.

[0008] Further, the DO content in the pool body of the transition MABR zone is controlled at 0.2 - 1.5 mg / L. When high limit requirements are put forward for the total nitrogen in the system effluent, the DO content in the pool body of the transition MABR zone is controlled at 0.2 - 0.5 mg / L; when the influent unit increases the influent treatment water volume, the DO content in the pool body of the transition MABR zone is controlled at 1.0 - 1.5 mg / L.

[0009] Further, the filtration unit filters or adsorbs impurities, suspended solids, and some microorganisms using granular filter media, and the granular filter media is selected from one or more of quartz sand, manganese sand, ceramsite, and activated carbon.

[0010] Further, metering devices are respectively designed in the anaerobic zone and anoxic MABR zone of the sludge external reflux system to control the reflux ratio respectively.

[0011] Further, in the method for using the MABR railway domestic sewage treatment system, monitoring systems are respectively set in the anoxic MABR zone, transition MABR zone, and aerobic MABR packing zone. The monitoring items include indicators such as ammonia nitrogen, nitrate nitrogen, total nitrogen, total phosphorus, dissolved oxygen, oxidation-reduction potential, etc. According to the monitoring results, the operating parameters of the air supply pressure, air supply flow, sludge reflux ratio, and hydraulic retention time in each zone are adjusted in a timely manner.

[0012] The present invention discloses a MABR-based railway domestic sewage treatment system and its usage method, which fully utilizes the respective advantages of the MABR technology and water treatment packing, efficiently removes pollutants through simultaneous nitrification and denitrification, better realizes nitrogen removal using the transition MABR zone, and further removes pollutants using the filtration unit, effectively solving the problem of railway line staff domestic sewage treatment, and achieving the high efficiency, stability, and sustainability of sewage treatment. The present invention has the advantages of high pollutant removal efficiency, no internal reflux of mixed liquor, reduced sludge production, energy conservation and carbon reduction, and easy operation. Specific Embodiments

[0013] To make the technical means, creative features, achieved purposes, and functions of the present invention easy to understand, the present invention is further described below in conjunction with specific embodiments.

[0014] A MABR-based railway domestic sewage treatment system, characterized in that it includes a sequentially connected inlet unit, anaerobic zone, anoxic MABR zone, transition MABR zone, aerobic MABR packing zone, sedimentation tank, filtration unit and clean water output unit, and also includes a sludge external reflux system and an air supply system; wherein, the anoxic MABR zone and the transition MABR zone are mainly composed of MABR membrane boxes; the aerobic MABR packing zone includes an MABR membrane treatment area and a biological packing area. The MABR membrane treatment area is arranged at the front end of the biological packing area. MABR membrane boxes are implanted in the MABR membrane treatment area, and curtain-type water treatment packing units are implanted in the biological packing area; the volume of the area where the MABR membrane boxes are located does not exceed 1 / 3 of the volume of the MABR packing zone; the reflux ratio in the sludge external reflux system is set to 50%-100%, 0%-50% is refluxed to the anaerobic zone, and 50%-100% is refluxed to the anoxic MABR zone; the air supply system is mainly composed of an air supply device, an air supply pipeline and a control valve. The air supply system supplies air to the anoxic MABR zone, the transition MABR zone and the aerobic MABR packing zone respectively, and the air supply volume and air supply pressure are adjusted through the control valve.

[0015] The usage method of the MABR-based railway domestic sewage treatment system includes the following steps: (1) Construction of the sewage treatment system: Connect the anaerobic zone, anoxic MABR zone, transition MABR zone, aerobic MABR packing zone and sedimentation tank in sequence. MABR membrane boxes and curtain-type water treatment packing units are implanted in the anoxic MABR zone, transition MABR zone and aerobic MABR packing zone respectively; an overpass connecting pipe is provided between the aerobic MABR packing zone and the sedimentation tank, and the MABR packing zone and the sedimentation tank are directly connected bypassing the filtration unit and the clean water output unit; turn on the air supply system to supply air to the anoxic MABR zone, transition MABR zone and aerobic MABR packing zone; (2) System film hanging and acclimation: Domestic sewage and activated sludge are put into the anaerobic zone, anoxic MABR zone, transition MABR zone and aerobic MABR packing zone from the inlet unit. The anoxic MABR zone, transition MABR zone and aerobic MABR packing zone are subjected to static aeration for 24 h and then intermittent water inlet. The film hanging and acclimation period is 5-7 d; (3) System commissioning and startup: Close the overpass connecting pipe provided between the aerobic MABR packing zone and the sedimentation tank, continuously inlet water from the inlet unit, and gradually reduce the total hydraulic retention time of the anaerobic zone, anoxic MABR zone, transition MABR zone and aerobic MABR packing zone from 48 h to 24 h, shortening by 2 h each time and operating for 3-5 d in each cycle, and regularly detect the water quality of the influent and effluent; (4)System operation: Connect the filtration unit, clean water output unit and sludge external reflux system into step (3). The influent unit continuously feeds water. The total hydraulic retention time in the anaerobic zone, anoxic MABR zone, transition MABR zone and aerobic MABR packing zone is maintained at 16 - 24 h and adjusted according to the treatment requirements. The air supply system supplies air to the anoxic MABR zone, transition MABR zone and aerobic MABR packing zone, monitors the DO concentration in the pool bodies of each zone, and adjusts the air supply pressure and air supply flow of each zone through valves. The sludge external reflux system respectively controls the sludge reflux ratios of the anaerobic zone and the anoxic MABR zone. Monitor the water quality of the influent unit and the clean water output unit.

[0016] During the use of the above system and method, the DO content in the pool body of the transition MABR zone is controlled at 0.2 - 1.5 mg / L. When a high limit requirement is put forward for the total nitrogen in the system effluent, the DO content in the pool body of the transition MABR zone is controlled at 0.2 - 0.5 mg / L. When the influent unit increases the influent treatment water volume, the DO content in the pool body of the transition MABR zone is controlled at 1.0 - 1.5 mg / L.

[0017] The filtration unit filters or adsorbs impurities, suspended solids and some microorganisms using granular filter media. The granular filter media is selected from one or more of quartz sand, manganese sand, ceramsite and activated carbon. Metering devices are respectively designed for the anaerobic zone and the anoxic MABR zone in the sludge external reflux system to respectively control the reflux ratios. In the method for using the MABR railway domestic sewage treatment system, monitoring systems are respectively set in the anoxic MABR zone, transition MABR zone and aerobic MABR packing zone. The monitoring items include indicators such as ammonia nitrogen, nitrate nitrogen, total nitrogen, total phosphorus, dissolved oxygen, oxidation-reduction potential, etc. The operating parameters of the air supply pressure, air supply flow, sludge reflux ratio and hydraulic retention time of each zone are adjusted in a timely manner according to the monitoring results.

[0018] Example 1: The domestic sewage treatment volume of a certain railway is 100 m 3 / d, with influent COD ≤ 300 mg / L, ammonia nitrogen ≤ 50 mg / L, and total nitrogen ≤ 60 mg / L, and the effluent indicators meeting the Class A standard of Discharge Standard of Pollutants for Municipal Wastewater Treatment Plants (GB 18918 - 2002). Using the MABR treatment system in the present invention, a railway domestic sewage treatment system based on MABR is established. Among them, the filtration unit uses quartz sand filter media. The system film hanging and acclimation period is selected as 7 days, and the commissioning period for large fluctuations in influent water quality is 30 days to reach stability. The total hydraulic retention time of the biochemical treatment unit is 22 h, and the DO content in the transition MABR area tank body is controlled at 0.2 - 1.5 mg / L, and the DO concentration is adjusted at any time according to the water quality situation. In the sludge external reflux system, the reflux ratio is set at 0% - 25% and refluxed to the anaerobic area, and about 50% is refluxed to the anoxic MABR area. The air supply system is equipped with 3 Roots blowers, operating in a mode of 2 in use and 1 standby, supplying air to the anoxic MABR area, the transition MABR area, and the aerobic MABR packing area. After 4 months of stable operation, the main effluent water quality indicators can meet the Class A standard of Discharge Standard of Pollutants for Municipal Wastewater Treatment Plants (GB 18918 - 2002) (COD ≤ 50 mg / L, ammonia nitrogen ≤ 5 mg / L).

[0019] The above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose is to enable ordinary technicians in the field to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention. Any technician familiar with the technical field, within the technical scope of the present invention, making equivalent substitutions or changes based on the technical solution and its concept of the present invention should be covered within the protection scope of the present invention.

Claims

1. A MABR-based railway domestic sewage treatment system, characterized in that: It includes a water inlet unit, an anaerobic zone, an anoxic MABR zone, a transition MABR zone, an aerobic MABR packing zone, a sedimentation tank, a filtration unit, and a clear water output unit that are connected in sequence, and also includes a sludge external reflux system and an air supply system; The anoxic MABR zone and the transition MABR zone are mainly composed of MABR membrane boxes; The aerobic MABR packing zone includes an MABR membrane treatment zone and a biological packing zone. The MABR membrane treatment zone is arranged at the front end of the biological packing zone. MABR membrane boxes are implanted in the MABR membrane treatment zone, and curtain-type water treatment packing units are implanted in the biological packing zone; the volume of the area where the MABR membrane boxes are located accounts for no more than 1 / 3 of the volume of the MABR packing zone; In the sludge external reflux system, the reflux ratio is set to 50%-100%, among which 0%-50% is refluxed to the anaerobic zone and 50%-100% is refluxed to the anoxic MABR zone; The air supply system is mainly composed of an air supply device, an air supply pipeline, and a control valve. The air supply system supplies air to the anoxic MABR zone, the transition MABR zone, and the aerobic MABR packing zone respectively, and the air supply volume and air supply pressure are adjusted through the control valve.

2. The usage method of the MABR-based railway domestic sewage treatment system according to claim 1, characterized in that: It includes the following steps: (1) Construction of the sewage treatment system: Connect the anaerobic zone, the anoxic MABR zone, the transition MABR zone, the aerobic MABR packing zone, and the sedimentation tank in sequence. MABR membrane boxes and curtain-type water treatment packing units are respectively implanted in the anoxic MABR zone, the transition MABR zone, and the aerobic MABR packing zone; an overpass connecting pipe is set between the aerobic MABR packing zone and the sedimentation tank, and the MABR packing zone and the sedimentation tank are directly connected bypassing the filtration unit and the clear water output unit; turn on the air supply system to supply air to the anoxic MABR zone, the transition MABR zone, and the aerobic MABR packing zone; (2) System film hanging and acclimation: Domestic sewage and activated sludge are put into the anaerobic zone, the anoxic MABR zone, the transition MABR zone, and the aerobic MABR packing zone from the water inlet unit. The anoxic MABR zone, the transition MABR zone, and the aerobic MABR packing zone are subjected to static aeration for 24 h and then intermittently fed with water. The film hanging and acclimation period is 5-7 d; (3) System commissioning and startup: Close the overpass connecting pipe set between the aerobic MABR packing zone and the sedimentation tank, continuously feed water from the water inlet unit, and gradually reduce the total hydraulic retention time of the anaerobic zone, the anoxic MABR zone, the transition MABR zone, and the aerobic MABR packing zone from 48 h to 24 h, shortening by 2 h each time and operating for 3-5 d in each cycle, and regularly detect the water quality of the influent and effluent; (4) System operation: Connect the filtration unit, the clear water output unit, and the sludge external reflux system into step (3). The water inlet unit continuously feeds water, and the total hydraulic retention time of the anaerobic zone, the anoxic MABR zone, the transition MABR zone, and the aerobic MABR packing zone is maintained at 16-24 h and adjusted according to the treatment requirements; the air supply system supplies air to the anoxic MABR zone, the transition MABR zone, and the aerobic MABR packing zone, monitors the DO concentration in the pool bodies of each zone, and adjusts the air supply pressure and air supply flow of each zone through the valve; the sludge external reflux system respectively controls the sludge reflux ratio of the anaerobic zone and the anoxic MABR zone; monitor the water quality of the water inlet unit and the clear water output unit.

3. The MABR-based railway domestic sewage treatment system and its usage method according to claims 1-2, characterized in that: The DO content in the transition MABR zone tank is controlled at 0.2 - 1.5 mg / L. When high limit requirements are put forward for the total nitrogen in the system effluent, the DO content in the transition MABR zone tank is controlled at 0.2 - 0.5 mg / L; when the influent unit increases the influent treatment water volume, the DO content in the transition MABR zone tank is controlled at 1.0 - 1.5 mg / L.

4. The MABR-based railway domestic sewage treatment system and its usage method according to claims 1-2, characterized in that: The filtration unit filters or adsorbs impurities, suspended solids and some microorganisms by using granular filter media, and the granular filter media is selected from one or more of quartz sand, manganese sand, ceramsite and activated carbon.

5. The MABR-based railway domestic sewage treatment system and its usage method according to claims 1-2, characterized in that: In the sludge external reflux system, metering devices are respectively designed for the anaerobic zone and the anoxic MABR zone to control the reflux ratio respectively.

6. The MABR-based railway domestic sewage treatment system and its usage method according to claims 1-2, characterized in that: In the usage method of the MABR-based railway domestic sewage treatment system, monitoring systems are respectively arranged in the anoxic MABR zone, the transition MABR zone and the aerobic MABR packing zone.