High-speed service area sewage treatment system and sewage treatment method thereof

Abstract

The invention relates to a high-speed service area sewage treatment system and a sewage treatment method thereof, and belongs to the technical field of sewage treatment. The device structurally comprises a grating, an adjusting tank, a biological selection tank, an MABR reaction tank, a secondary sedimentation tank, an intermediate water tank, a sand filter tank and a clean water tank which are connected in sequence, the secondary sedimentation tank is connected with a sludge concentration tank, and a small amount of sludge in the sludge concentration tank and a small amount of sludge in the clean water tank are discharged into a residual sludge discharge tank; most of the sludge in the sludge thickening tank passes through the stacked spiral sludge dewatering machine and the sludge in the residual sludge discharge tank to be transported outwards. The sewage treatment system for the high-speed service area can effectively realize resource utilization of sewage, reduce environmental pollution and protect a surrounding ecological system.

Description

Technical Field

[0001] The invention relates to a high-speed service area sewage treatment system and a sewage treatment method thereof, belonging to the technical field of sewage treatment. Background Art

[0002] With the continuous expansion and improvement of my country's highway network, the number of highway service areas, as important places that provide rest, dining, refueling and other services for passing vehicles and drivers and passengers, is also increasing. Highway service areas generate a large amount of sewage during operation, which mainly comes from toilet flushing water, catering wastewater, vehicle flushing water and staff living water in the service area. If it is discharged directly without proper treatment, it will cause serious pollution to the surrounding soil and water environment, affect the balance of the surrounding ecosystem, and may even pollute nearby rivers, lakes and other water resources, thereby endangering the water safety and biodiversity of downstream areas. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a high-speed service area sewage treatment system, which can effectively realize sewage resource utilization, reduce environmental pollution, and protect the surrounding ecosystem.

[0004] To solve the above problems, the specific technical scheme of the present invention is as follows: a high-speed service area sewage treatment system, comprising a grid, a regulating tank, a biological selection tank, a MABR reaction tank, a secondary sedimentation tank, an intermediate water tank, a sand filter tank, and a clear water tank connected in sequence; a sludge thickening tank is connected to the secondary sedimentation tank, and a small amount of sludge in the sludge thickening tank and a small amount of sludge in the clear water tank are discharged into a residual sludge discharge tank; most of the sludge in the sludge thickening tank is transported out through a screw stack sludge dewatering machine and the sludge in the residual sludge discharge tank.

[0005] A sludge return pipeline is provided between the secondary sedimentation tank and the biological selection tank.

[0006] A carbon source dosing system is arranged between the regulating tank and the biological selection tank; the carbon source dosing system adds carbon source.

[0007] A phosphorus removal dosing system is installed between the MABR reaction tank and the secondary sedimentation tank; the phosphorus removal agent of the phosphorus removal dosing system is polyaluminium chloride.

[0008] The MABR reaction tank is composed of a plurality of membrane modules. The membrane materials in the membrane modules have good air permeability and bio-affinity, and are installed in a container in a modular assembly manner to reduce civil construction.

[0009] The secondary sedimentation tank is a radial flow secondary sedimentation tank, and the slope of the tank bottom is not less than 0.05.

[0010] A flow metering device is provided between the sand filter tank and the clean water tank.

[0011] A sewage treatment method based on a high-speed service area sewage treatment system comprises the following steps: 1) After being lifted and merged by the inlet pump, the wastewater from the highway service area first flows to the screen, where larger suspended particles can be filtered and removed. The filtered wastewater flows into the biological selection tank by gravity in the regulating tank, and the return sludge also flows back to the selection tank. The chemical oxygen demand, biological oxygen demand, suspended solids, etc. are first treated in order to improve the operating conditions of the MABR reaction tank and reduce the load; 2) Then it enters the MABR reaction tank. The MABR reaction tank uses the synergistic effect between the selective permeable membrane and the attached growth type biofilm to transfer oxygen to the biofilm attached to the surface of the permeable membrane through the permeable membrane. At the same time, pollutants diffuse from the sewage into the biofilm for treatment; 3) After the MABR process, the biological oxygen demand and ammonia nitrogen components in the sewage are effectively removed, but the sewage still needs to pass through the radial flow secondary sedimentation tank to achieve the effect of mud and water separation. The liquid in the secondary sedimentation tank flows to the sand filter tank and the clear water tank in turn through the buffering effect of the intermediate water tank, and a small amount of residual sludge in the clear water tank is discharged; 4) Part of the remaining sludge in the secondary sedimentation tank is returned to the biological selection tank by the pump. Finally, the sludge produced by the biological selection tank, MABR reaction tank and secondary sedimentation tank is pumped into the sludge thickening tank. It is dehydrated by the dosing system and the spiral sludge dewatering machine to form a mud cake, which is then transported out together with the remaining sludge in step 3).

[0012] This application adopts the above technical solution, which has the following beneficial effects: 1. Effectively provide sewage treatment system for highway service areas. The system has compact structure and small footprint, which is suitable for installation and use in highway service areas with limited land resources; 2. This application has a high degree of automation, simple operation and maintenance, low aeration energy consumption, long service life of core equipment, and low maintenance frequency. These multiple advantages make the operation and maintenance cost of the MABR process much lower than traditional processes such as AO+MBR. From the perspective of the 15-year full life cycle, the MABR process can achieve low life cycle costs, while meeting national and local high emission standards, and gaining greater economic benefits; 3. The setting of the sludge dewatering device in this application realizes the reduction, stabilization and harmless treatment of sludge, and reduces the secondary pollution of sludge to the environment; 4. The flow metering equipment of this application can accurately measure the discharge of sewage and provide data support for the rational use and management of water resources; 5. This application proposes an operational solution to the common problems faced by highway service areas. The effluent treated by this technical solution can eventually meet the reuse water standards due to the MABR process, which greatly reduces production costs and complies with the development concept of green environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a structural diagram of the sewage treatment system in the highway service area.

[0014] Figure 2 This is the structural diagram of the MABR reaction tank. DETAILED DESCRIPTION

[0015] like Figure 1 As shown, a sewage treatment system for a highway service area includes a grille 1, a regulating tank 2, a biological selection tank 3, a MABR reaction tank 4, a secondary sedimentation tank 5, an intermediate water tank 6, a sand filter 7, a clean water tank 8 and a residual sludge discharge tank 12 connected in sequence; a sludge concentration tank 9 is connected in sequence to the secondary sedimentation tank 5, and a small amount of sludge in the sludge concentration tank 9 and a small amount of sludge in the clean water tank 8 are discharged into the residual sludge discharge tank 14; most of the sludge in the sludge concentration tank 9 passes through a screw stacking sludge dewatering machine 10 and the sludge in the residual sludge discharge tank 14 for sludge transport.

[0016] In this embodiment, the outlet of the clean water tank 8 can be connected to a drain pipe so that the qualified water can be directly discharged; or, the outlet of the clean water tank 8 can be connected to a water unit of a highway service area through a return pipe so that the water treated by the sewage treatment system can flow back to the water unit, thereby realizing the recycling of sewage. Here, the qualified water can be discharged into the drain pipe or the water unit through a pump.

[0017] A sludge return pipeline is provided between the secondary sedimentation tank 5 and the biological selection tank 3. The secondary sedimentation tank adopts a common radial flow sedimentation tank and is circular. The slope of the bottom of the tank is not less than 0.05, and a return pump is installed with a design flow rate of 10 m 3 / h, head is 10m, power is 0.75 kW. Most of the bottom sludge is returned to the biological selection tank, and a small amount of sludge is dehydrated by the desludging machine as residual sludge and then transported out.

[0018] A carbon source dosing system 11 is provided between the regulating tank 2 and the biological selection tank 3; a dephosphorization dosing system 12 is provided between the MABR reaction tank 4 and the secondary sedimentation tank 5. The carbon source dosing system 11 is charged with a carbon source; and the dephosphorization agent of the dephosphorization dosing system 12 is polyaluminum chloride.

[0019] like Figure 2As shown in FIG. 1 , the MABR reaction tank 4 is composed of four MABR membrane modules. The membrane materials in the membrane modules have good air permeability and bioaffinity and are installed in a container in a modular assembly manner. The specific surface area of ​​each membrane module is not less than 1 200 m 2 / m 3 , a total of 2 containers, each container has an effective volume of 70 m 3 , HRT is 16.8 h, thus reducing civil construction.

[0020] The sand filter 7 removes suspended solids, microorganisms and fine particles through the filter medium. The sand filter 7 is integrated in the comprehensive equipment room and is equipped with a sand filter backwash pump with a design flow rate of 53 m 3 / h, the power is 5.5 kW. A flow metering device 13 is provided between the sand filter 7 and the clean water tank 8.

[0021] The sewage treatment method based on the above-mentioned high-speed service area sewage treatment system comprises the following steps: 1) After being lifted and merged by the inlet pump, the wastewater from the highway service area first flows to the screen 1, where larger suspended particles can be filtered and removed. The filtered wastewater flows into the biological selection tank 3 by gravity in the regulating tank 2, and the return sludge also flows back to the selection tank 3. The chemical oxygen demand, biological oxygen demand, suspended solids, etc. are first treated in order to improve the operating conditions of the MABR reaction tank 4 and reduce the load; the effective volume of the regulating tank is 159.1 m 3 , HRT is 19.1 h. A mechanical screen is installed, the screen width is 750 mm, the screen gap is 3 mm; 2 submersible sewage pumps, the head is 9 m, the flow rate is 10 m 3 / h, 1 set of liquid level control system. Regulating valves and flow meters are respectively set at the water inlet ends of the regulating tank 2, biological selection tank 3, and MABR reaction tank 4, so as to adjust the flow rate at any time according to the actual situation.

[0022] 2) Then it enters the MABR reaction tank 4, which uses the synergistic effect between the selective permeable membrane and the attached growth type biofilm to transfer oxygen to the biofilm attached to the surface of the permeable membrane through the permeable membrane, and at the same time, pollutants diffuse from the sewage into the biofilm for treatment; 3) After the MABR process, the biological oxygen demand, ammonia nitrogen and other components in the sewage are effectively removed, but the sewage still needs to pass through the radial flow secondary sedimentation tank 5 to achieve the effect of mud and water separation. The liquid in the secondary sedimentation tank 5 flows to the sand filter 7 and the clean water tank 8 in turn through the buffering effect of the intermediate water tank 6. A small amount of residual sludge in the clean water tank 8 can be discharged; 4) Part of the remaining sludge in the secondary sedimentation tank 5 is returned to the biological selection tank 3 by the action of the pump. Finally, the sludge produced by the biological selection tank 3, the MABR reaction tank 4 and the secondary sedimentation tank 5 is pumped into the sludge thickening tank 9, and is dehydrated by the dosing system and the spiral sludge dewatering machine 10 to form a mud cake, which is then transported out together with the remaining sludge in step 3).

Claims

1. A high-speed service area sewage treatment system, characterized by: The invention comprises a screen (1), a regulating tank (2), a biological selection tank (3), a MABR reaction tank (4), a secondary sedimentation tank (5), an intermediate water tank (6), a sand filter tank (7), and a clear water tank (8) which are connected in sequence; a sludge thickening tank (9) is connected to the secondary sedimentation tank (5); a small amount of sludge in the sludge thickening tank (9) and a small amount of sludge in the clear water tank (8) are discharged into a residual sludge discharge tank (14); most of the sludge in the sludge thickening tank (9) passes through a screw stacking sludge dewatering machine (10) and the sludge in the residual sludge discharge tank (14) for sludge transport.

2. The high-speed service area sewage treatment system according to claim 1 is characterized by: A sludge return pipeline is provided between the secondary sedimentation tank (5) and the biological selection tank (3).

3. The highway service area sewage treatment system according to claim 2 is characterized by: A carbon source dosing system (11) is provided between the regulating tank (2) and the biological selection tank (3); the carbon source dosing system (11) adds a carbon source.

4. The highway service area sewage treatment system according to claim 3 is characterized by: A phosphorus removal dosing system (12) is provided between the MABR reaction tank (4) and the secondary sedimentation tank (5); the phosphorus removal agent of the phosphorus removal dosing system (12) is polyaluminium chloride.

5. The highway service area sewage treatment system according to claim 1, characterized in that: The MABR reaction tank (4) is composed of a plurality of membrane modules. The membrane materials in the membrane modules have good air permeability and biocompatibility, and are installed in a container in a modular assembly manner to reduce civil construction.

6. The highway service area sewage treatment system according to claim 1, characterized in that: The secondary sedimentation tank (5) is a radial flow secondary sedimentation tank, and the slope of the tank bottom is not less than 0.

05.

7. The highway service area sewage treatment system according to claim 1, characterized in that: A flow metering device (13) is provided between the sand filter tank (7) and the clean water tank (8).

8. A sewage treatment method based on the high-speed service area sewage treatment system according to claim 4, characterized in that The following steps are involved: 1) After being lifted and merged by the inlet pump, the wastewater from the highway service area first flows to the screen (1), where larger suspended particles can be filtered and removed. The filtered wastewater flows into the biological selection tank (3) by gravity in the regulating tank (2), and the return sludge also flows back to the selection tank (3) to firstly treat the chemical oxygen demand, biological oxygen demand, suspended solids, etc., so as to improve the operating conditions of the MABR reaction tank (4) and reduce the load; 2) Then it enters the MABR reaction tank (4). The MABR reaction tank (4) uses the synergistic effect between the selective permeable membrane and the attached growth type biofilm to transfer oxygen to the biofilm attached to the surface of the permeable membrane through the permeable membrane. At the same time, pollutants diffuse from the sewage into the biofilm for treatment; 3) After the MABR process, the biological oxygen demand and ammonia nitrogen components in the sewage are effectively removed, but the sewage still needs to pass through the radial flow secondary sedimentation tank (5) to achieve the effect of mud and water separation. The liquid in the secondary sedimentation tank (5) flows to the sand filter tank (7) and the clean water tank (8) in turn through the buffering effect of the intermediate water tank (6), and a small amount of residual sludge in the clean water tank (8) is discharged; 4) Part of the remaining sludge in the secondary sedimentation tank (5) is returned to the biological selection tank (3) by the action of the pump. Finally, the sludge produced by the biological selection tank (3), the MABR reaction tank (4) and the secondary sedimentation tank (5) is pumped into the sludge thickening tank (9) and dehydrated by the dosing system and the screw-type sludge dewatering machine (10) to form a sludge cake, which is then transported out together with the remaining sludge in step 3).

Images