MABR-based comprehensive treatment method for park water

Abstract

The invention discloses an MABR-based park water comprehensive treatment method, and belongs to the technical field of sewage treatment, the system comprises a water inlet system, an adjusting tank, an MABR system, a second MABR system, a sedimentation tank, a filtration, disinfection and reuse water tank, an air supply system, and a treatment system taking mixed water of park toilet flushing discharge water and park lake water as a water source, a first set of MABR system is arranged in a lake, pollutants in an inflow water mixed solution are degraded by utilizing an MABR technology, a second set of MABR system is arranged in the lake to further degrade the pollutants and provide dissolved oxygen content for water in the lake, and effluent of the MABR system is subjected to advanced treatment by combining with a filtration and disinfection technology and then is recycled and pumped into a toilet flushing water system, so that the recycling of water resources is achieved; water resources are saved, meanwhile, sewage discharge is reduced, and the park water environment is improved. The sewage treatment method has the advantages of being simple in process, small in occupied area, small in sludge amount, good in treatment effect, easy to popularize and apply and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of sewage treatment, and specifically relates to a comprehensive water treatment method for parks based on MABR. Background Art

[0002] Urban parks are a vital component of urban ecosystems, playing an irreplaceable role in improving the urban environment and providing recreational spaces. However, flushing water from public restrooms in parks contains large amounts of organic matter and nutrients and cannot be discharged directly. High-load discharge into the urban sewage network also places a strain on the receiving system. Furthermore, the long-term use of the park's lake is subject to multiple factors, including rainwater erosion and boating activities, which gradually deteriorate its water quality and disrupt the lake's ecological balance.

[0003] Traditional methods mostly involve collecting park wastewater and discharging it into the municipal sewer network, which increases the burden on sewage treatment plants. Furthermore, park lake water is often treated through methods such as water exchange or physical filtration, which are relatively costly, have limited effectiveness, and do not fully utilize water resources. Conventional water treatment processes for park wastewater treatment require consideration of various requirements, such as land area and effluent reuse. Simple treatment cannot be used for public restroom flushing, and the effluent from public restroom flushing is not well treated.

[0004] The membrane aerated biofilm reactor (MABR) is an emerging wastewater treatment technology. Its core technology is the oxygen-permeable membrane and the biofilm on its surface. The MABR is used to supply oxygen to the biofilm, allowing microorganisms to attach to the outer surface of the membrane filaments to form a biofilm. The outer surface of the MABR membrane filaments forms an aerobic / anoxic / anaerobic microbial structure from the inside out, which forms an opposite direction of mass transfer with the pollutants in the sewage, thereby achieving efficient degradation of water pollutants and improving sewage treatment efficiency. At the same time, MABR technology has the advantages of small footprint, low energy consumption and simple operation. When combined with processes such as filtration and disinfection, it can further improve the effluent water quality and achieve efficient reuse of water resources. The development of a comprehensive water management method for parks based on MABR has important practical significance and broad application prospects for improving the efficiency of water resource utilization and the ecological environment of parks. Summary of the Invention

[0005] In summary, the present invention provides a treatment system that uses the mixed water of park toilet flushing discharge and lake water in the park as the water source. It uses MABR technology combined with filtration and disinfection to form an integrated technology to improve the efficiency of pollutant degradation, and reuse the treated water to achieve water resource management and reuse, thereby saving water resources, reducing sewage discharge and improving the park water environment.

[0006] The present invention is achieved through the following technical solutions: The MABR park water management method is characterized by the following features: the system consists of a water inlet system, a regulating tank, a MABR system, a second MABR system, a sedimentation tank, a filtration tank, a disinfection tank, a reuse tank, and an air supply system. The method of using the system includes the following steps: 1) Obtaining the influent mixture: Park lake water and toilet flushing water are mixed in the regulating tank to obtain the influent mixture; 2) Construction of the secondary biochemical treatment system: The MABR system consists of an anoxic tank and an aerobic tank connected in series. A second MABR system is set up in the non-recreational area of ​​the lake with enclosures, and both systems are equipped with at least one MABR treatment unit. 3) Biofilm cultivation and acclimation: The MABR system uses activated sludge, influent mixture, and nutrients to inoculate and cultivate microorganisms in the MABR system. All effluent from the MABR system enters the second MABR system. The second MABR system uses the natural biofilm cultivation method for acclimation. The influent receives a mixture of MABR system effluent and lake water, with a mixed water ratio of 1:5-1:1. 4) Process selection: Different process flows are adopted based on the required volume of toilet flush water. When toilet flush water is in use, part of the water from the MABR system enters the advanced treatment and reuse system and is pumped into the toilet flush water system. The advanced treatment system mainly includes a filtration unit, a disinfection unit, and a reuse water tank. When toilet flush water is not in use, the water discharged from the MABR system enters the second MABR system, where it is further treated and discharged into the lake. 5) Operation: After the acclimation of the MABR system and the 2#MABR system is completed, the system operates continuously. The influent mixture enters the MABR system and the sedimentation tank in sequence. The effluent after sedimentation and separation enters the 2#MABR system and the deep treatment and reuse system respectively. The HRT, air supply pressure and DO content of the MABR system and the 2#MABR system are adjusted according to the water quality and treatment requirements of the influent mixture. After treatment, they meet the requirements for lake water and toilet flushing water respectively. In step 1), the proportion of toilet flushing water in the total water volume in the influent mixture is controlled to be 20% or less; In step 2), an inlet area and a discharge area are set up in the 2#MABR system area, and the water is discharged into the lake; The MABR treatment unit in step 2) is mainly composed of a MABR membrane box, an air supply system and a control and monitoring system, and one or more MABR membrane boxes are used in parallel; In steps 2) and 3), the MABR system and the 2#MABR system share a common air supply system; The MABR system acclimation period in step 3) is divided into three stages: stage 1: activated sludge is inoculated once, nutrients are added, and after 24 hours of aeration, the influent mixture is 100% lake water, the hydraulic retention time (HRT) is 24 hours, and the cycle is 7-14 days; stage 2: the proportion of toilet flush water in the influent mixture is 5%, 10%, 15% and 20% respectively, and each concentration gradient acclimation cycle is 5-7 days, with an HRT of 24 hours; stage 3: the influent mixture is maintained at the level of stage 2, the HRT is shortened to 20 hours, and the cycle is 5-7 days; the acclimation is completed when a dense biofilm is formed on the outer surface of the membrane fibers and the removal rate of major pollutants in the MABR system reaches 80% or above; The natural biofilm culture acclimatization period of the 2#MABR system in step 3) is the same as the total period of the MABR system, and the HRT is 24 hours.

[0007] Preferably, the regulating tank receives toilet flushing water and lake water, and the tank body is designed to be semi-underground or underground, and the volume meets the water consumption of 0.5d.

[0008] Preferably, the MABR system equipment is configured as an above-ground type, a semi-above-ground type or an underground type according to the land occupation requirements.

[0009] Preferably, a water pump and a valve are provided in the deep treatment and reuse system, and the water pump supplies water to the toilet flushing water system through a water supply pipeline.

[0010] Preferably, the filtration unit adopts at least one of quartz sand, manganese sand, anthracite and activated carbon, and the filtration unit adopts one-stage or two-stage series filtration.

[0011] Preferably, the disinfection unit uses at least one of sodium hypochlorite, ozone or ultraviolet rays.

[0012] Comprehensive management of toilet flushing water and lake water in the park can bring the following good results: (1) After comprehensive treatment, the sewage in the park has been well treated, achieving resource reuse of the park’s sewage, reducing dependence on municipal water supply, and lowering the park’s operating costs; (2) Part of the water is discharged into the park water body after treatment, and a 2#MABR system is installed in the park water body to achieve in-situ purification of the lake water, which helps to improve and maintain the water quality of the park water body and restore the self-purification capacity of the water body, enhance the ecological environment function of the park, and has good environmental benefits.

[0013] (3) MABR technology combines sedimentation, filtration and disinfection processes, and its treatment effect is stable and reliable. It can effectively remove organic matter in sewage and the effluent water quality is good.

[0014] (4) The entire treatment system has a high degree of automation and is easy to operate and manage. It can be used in above-ground, semi-underground or underground types, saving a lot of public space for the park and is suitable for promotion and application in the park.

[0015] The present invention discloses a comprehensive park water management method based on MABR (Manufactured Refrigeration and Braking) technology. The treatment system uses a mixture of park toilet flushing discharge and park lake water as its water source. MABR technology is used to degrade pollutants in the influent mixture. A second MABR system is installed in the lake to further degrade pollutants and simultaneously provide dissolved oxygen to the lake water. The MABR system effluent is deeply treated with filtration and disinfection technology before being reused. The water is then pumped into the toilet flushing water system, achieving water resource reuse, saving water resources, reducing sewage discharge, and improving the park water environment. This sewage treatment method has the advantages of simple process, small footprint, low sludge volume, good treatment effect, and easy application. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Attachment Figure 1 It is a schematic diagram of the process flow of the present invention. DETAILED DESCRIPTION

[0017] In order to make the technical means, creative features, objectives and effects of the present invention easier to understand, please refer to Figure 1 , the present invention is further explained below in conjunction with specific implementation methods.

[0018] A treatment system and its use method were invented, which uses a mixture of park toilet flushing discharge water and lake water in the park as the water source. MABR technology is used to degrade pollutants in the influent mixture. A second MABR system is installed in the lake to further degrade the pollutants. At the same time, part of the MABR system's effluent is filtered and disinfected to meet the reuse requirements of toilet flushing water, and is collected and reused.

[0019] The system used in the MABR park water comprehensive treatment method includes the water inlet system, regulating tank, MABR system, 2#MABR system, sedimentation tank, filtration, disinfection, reuse water tank and air supply system. The specific use method includes the following steps: 1) Obtaining the influent mixture: Park lake water and toilet flushing water are mixed in the regulating tank to obtain the influent mixture; 2) Construction of the secondary biochemical treatment system: The MABR system consists of an anoxic tank and an aerobic tank connected in series. A second MABR system is set up in the non-recreational area of ​​the lake with enclosures, and both systems are equipped with at least one MABR treatment unit. 3) Biofilm cultivation and acclimation: The MABR system uses activated sludge, influent mixture, and nutrients to inoculate and cultivate microorganisms in the MABR system. All effluent from the MABR system enters the second MABR system. The second MABR system uses the natural biofilm cultivation method for acclimation. The influent receives a mixture of MABR system effluent and lake water, with a mixed water ratio of 1:5-1:1. 4) Process selection: Different process flows are adopted based on the required volume of toilet flush water. When toilet flush water is in use, part of the water from the MABR system enters the advanced treatment and reuse system and is pumped into the toilet flush water system. The advanced treatment system mainly includes a filtration unit, a disinfection unit, and a reuse water tank. When toilet flush water is not in use, the water discharged from the MABR system enters the second MABR system, where it is further treated and discharged into the lake. 5) Operation: After the acclimation of the MABR system and the 2#MABR system is completed, the system operates continuously. The influent mixture enters the MABR system and the sedimentation tank in sequence. The effluent after sedimentation and separation enters the 2#MABR system and the deep treatment and reuse system respectively. The HRT, air supply pressure and DO content of the MABR system and the 2#MABR system are adjusted according to the water quality and treatment requirements of the influent mixture. After treatment, they meet the requirements for lake water and toilet flushing water respectively.

[0020] In the above steps, it is required that the proportion of toilet flushing water in the influent mixture in step 1) be controlled at 20% or less; in step 2) an influent area and a drainage area are set up in the 2#MABR system area, and the water is discharged into the lake; in step 2) the MABR treatment unit is mainly composed of a MABR membrane box, an air supply system and a control and monitoring system, and one or more MABR membrane boxes are used in parallel; in steps 2) and 3), the MABR system and the 2#MABR system share a set of air supply systems; in step 3) the MABR system cultivation and acclimation period is divided into three stages, stage 1: one-time inoculation of activated sludge, addition of nutrients, and 24 hours of exposure after the influent mixture is 100% Lake water, hydraulic retention time (HRT) 24h, cycle 7-14d; Stage 2: the proportion of toilet flushing water in the influent mixture is 5%, 10%, 15% and 20% respectively, each concentration gradient acclimation cycle is 5-7d, HRT is 24h; Stage 3: maintain the influent mixture of Stage 2, shorten the HRT to 20h, cycle 5-7d; a dense biofilm is formed on the outer surface of the membrane fibers, and the removal rate of major pollutants in the MABR system reaches 80% or above, indicating that the cultivation acclimation is completed; the natural biofilm cultivation acclimation cycle of the 2#MABR system in step 3) is the same as the total cycle of the MABR system, and the HRT is selected as 24h.

[0021] Example 1: The total flushing water volume of adjacent toilets in a park is about 15m 3 / d, there is an artificial lake, some areas have boating entertainment activities, and the MABR system is designed to treat 100m3 of water. 3 / d, the water treatment capacity of the enclosed area of ​​2#MABR system is about 500-800m 3 / d, since the park flushing water collection pipeline is an underground pipeline, the regulating tank is designed to be underground, and the volume of the regulating tank is 50m 3 , and a water pump is set in the regulating tank, and the influent mixed liquid is supplied to the MABR system by the water pump. The MABR system is designed as a semi-underground type, with four zones: the MABR anoxic treatment zone, the MABR microaerobic treatment zone, the second MABR anoxic treatment zone and the MABR aerobic treatment zone, which are connected in sequence. MABR treatment units are installed in each of the MABR anoxic treatment zone, the MABR microaerobic treatment zone, the second MABR anoxic treatment zone and the MABR aerobic treatment zone. The difference is that the number of MABR treatment units in each zone is different, and the biofilm growth conditions and dissolved oxygen control conditions controlled in each zone are different. The number of MABR treatment units installed in the MABR anoxic treatment zone, the MABR microaerobic treatment zone, the second MABR anoxic treatment zone and the MABR aerobic treatment zone are 2 groups, 4 groups, 4 groups and 8 groups respectively; the hydraulic retention time of each zone during the culture acclimation period is 24h. The MABR system and the 2#MABR system are constructed according to the above method. The stages of biofilm culture acclimation period are as follows: MABR system: Phase 1: One-time inoculation of activated sludge. The activated sludge comes from the sedimentation sludge of the sewage treatment plant. Carbon, nitrogen and phosphorus nutrients are added. After 24 hours of aeration, water is added. The hydraulic retention time (HRT) is 24 hours. Water is continuously added. The water source is lake water. The cycle is 10 days. Phase 2: In Phase 1, a layer of biofilm forms on the outer surface of the MABR membrane fibers. The influent mixture begins to mix with toilet flush water. The proportion of toilet flush water is 5%, 10%, 15% and 20% respectively. Each concentration gradient acclimation cycle is 5 days. The HRT of each concentration gradient is 24 hours. Water is continuously added to optimize the bacterial species in the microbial film. At the same time, the water quality indicators of the MABR system effluent are monitored. Phase 3: Continuous operation is continued. The proportion of toilet flush water in the influent mixture is 20%. The HRT of the MABR system is shortened to 20 hours. The cycle is 7 days. The dense biofilm formed on the outer surface of the membrane fibers is more abundant. The removal rate of major pollutants in the MABR system reaches 80% or above, indicating that the culture acclimation is complete.

[0022] The effluent from the MABR system is closed and enters the deep treatment pipeline, and then enters the 2#MABR system for further treatment. After treatment, it is directly discharged into the park lake. When the MABR system is undergoing biofilm cultivation and acclimation, the 2#MABR system undergoes natural biofilm formation without adding nutrients during the period. The HRT is 24h, and the lake water body is used for continuous water inflow and outflow for biofilm cultivation and acclimation.

[0023] After the cultivation and acclimation of the MABR system, it was officially put into use. The dissolved oxygen content in the MABR anoxic treatment zone and the second MABR anoxic treatment zone was controlled at 0.2-0.5 mg / L, the dissolved oxygen content in the MABR microaerobic treatment zone was controlled at 0.5-1.5 mg / L, and the dissolved oxygen content in the MABR aerobic treatment zone was controlled at 1.5-2.5 mg / L. The dissolved oxygen content in each zone was regulated according to the influent water quality and toilet flushing water requirements. After sedimentation in the MABR system, the effluent entered the deep treatment and reuse system. The deep treatment mainly consisted of a filtration unit and a disinfection unit. The filtration unit adopted a dual filtration system - filtration system 1 was a quartz sand and anthracite dual filter media filtration unit, and filtration system 2 was an activated carbon filtration unit; disinfection adopted an ozone + sodium hypochlorite dual disinfection system. The water after deep treatment was supplied to the toilet flushing water through the water pump supply pipeline and was controlled by a valve at the same time.

[0024] The 2#MABR system receives the remaining water that is not used for toilet flushing in the MABR system, and also continuously enters the lake water. Through the MABR technology, the pollutants in the water are further degraded to meet the standards for lake water reception, thereby better realizing the purification and utilization of lake water.

[0025] The water output from the MABR system and the 2#MABR system meets the requirements for toilet flushing water and lake water respectively, realizing the management of water resources while greatly improving the park's water body. MABR technology has the advantages of high efficiency and low energy consumption, providing good technical support for park water body management.

[0026] The above embodiments are merely illustrative of the technical concepts and features of the present invention, and are intended to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent replacement or modification made by a person skilled in the art based on the technical solutions and concepts of the present invention within the technical scope of the present invention shall be encompassed within the scope of protection of the present invention.

Claims

1. A comprehensive water management method for parks based on MABR, characterized by: The system consists of a water inlet system, a regulating tank, a MABR system, a second MABR system, a sedimentation tank, a filtration tank, a disinfection tank, a recycled water tank and an air supply system. The method of using the system includes the following steps: 1) Obtaining the influent mixture: Park lake water and toilet flushing water are mixed in the regulating tank to obtain the influent mixture; 2) Construction of the secondary biochemical treatment system: The MABR system consists of an anoxic tank and an aerobic tank connected in series. A second MABR system is set up in the non-recreational area of ​​the lake with enclosures, and both systems are equipped with at least one MABR treatment unit. 3) Biofilm cultivation and acclimation: The MABR system uses activated sludge, influent mixture, and nutrients to inoculate and cultivate microorganisms in the MABR system. All effluent from the MABR system enters the second MABR system. The second MABR system uses the natural biofilm cultivation method for acclimation. The influent receives a mixture of MABR system effluent and lake water, with a mixed water ratio of 1:5-1:

1. 4) Process selection: Different process flows are adopted based on the required volume of toilet flush water. When toilet flush water is in use, part of the water from the MABR system enters the advanced treatment and reuse system and is pumped into the toilet flush water system. The advanced treatment system mainly includes a filtration unit, a disinfection unit, and a reuse water tank. When toilet flush water is not in use, the water discharged from the MABR system enters the second MABR system, where it is further treated and discharged into the lake. 5) Operation: After the acclimation of the MABR system and the 2#MABR system is completed, the system operates continuously. The influent mixture enters the MABR system and the sedimentation tank in sequence. The effluent after sedimentation and separation enters the 2#MABR system and the deep treatment and reuse system respectively. The HRT, air supply pressure and DO content of the MABR system and the 2#MABR system are adjusted according to the water quality and treatment requirements of the influent mixture. After treatment, they meet the requirements for lake water and toilet flushing water respectively. In step 1), the proportion of toilet flushing water in the total water volume in the influent mixture is controlled to be 20% or less; In step 2), an inlet area and a outlet area are set up in the 2#MABR system area, and the water is discharged into the lake; The MABR treatment unit in step 2) is mainly composed of a MABR membrane box, an air supply system and a control and monitoring system, and one or more MABR membrane boxes are used in parallel; In steps 2) and 3), the MABR system and the 2#MABR system share a common air supply system; The MABR system acclimation period in step 3) is divided into three stages: stage 1: activated sludge is inoculated once, nutrients are added, and after 24 hours of aeration, the influent mixture is 100% lake water, the hydraulic retention time (HRT) is 24 hours, and the cycle is 7-14 days; stage 2: the proportion of toilet flush water in the influent mixture is 5%, 10%, 15% and 20% respectively, and each concentration gradient acclimation cycle is 5-7 days, with an HRT of 24 hours; stage 3: the influent mixture is maintained at the level of stage 2, the HRT is shortened to 20 hours, and the cycle is 5-7 days; the acclimation is completed when a dense biofilm is formed on the outer surface of the membrane fibers and the removal rate of major pollutants in the MABR system reaches 80% or above; The natural biofilm culture acclimatization period of the 2#MABR system in step 3) is the same as the total period of the MABR system, and the HRT is 24 hours.

2. The MABR-based park water comprehensive treatment method according to claim 1, characterized in that: The regulating pool receives toilet flushing water and lake water, and the pool body is designed to be semi-underground or underground, and the volume meets the water consumption of 0.5d.

3. The MABR-based park water comprehensive treatment method according to claim 1, characterized in that: The MABR system equipment is configured as an above-ground type, a semi-above-ground type or an underground type according to the land occupation requirements.

4. The MABR-based park water comprehensive treatment method according to claim 1, characterized in that: A water pump and a valve are provided in the deep treatment and reuse system, and the water pump supplies water to the toilet flushing water system through a water supply pipeline.

5. The MABR-based park water comprehensive treatment method according to claim 1, characterized in that: The filtering unit adopts at least one of quartz sand, manganese sand, anthracite and activated carbon, and the filtering unit adopts one-stage or two-stage series filtration.

6. The MABR-based park water comprehensive treatment method according to claim 1, characterized in that: The disinfection unit uses at least one of sodium hypochlorite, ozone or ultraviolet rays.

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