Sewage treatment device
By introducing a rotary biological filter into the sewage treatment system, the problems of low oxygen utilization rate of the aerobic tank and blockage of the microporous aerator are solved, and more efficient oxygen utilization and a more stable treatment process are achieved.
Patent Information
- Application Number
- CN202520465842.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-18
- Publication Date
- 2025-05-02
- Estimated Expiration
- 2035-03-18
AI Technical Summary
In the existing sewage treatment technology, the oxygen utilization rate of the aerobic tank is low, resulting in an increase in aeration energy consumption and the microporous aerator is prone to clogging.
The rotary biological filter is used to expose the biofilm to the air through the rotation of the biological filter, which improves oxygen utilization and avoids the problem of blockage in pipeline aeration.
It improves the oxygen utilization rate during sewage treatment, reduces aeration energy consumption, and avoids the problem of blockage of microporous aerators, and improves the processing efficiency and equipment reliability.
Smart Images
Figure CN222821351U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of water treatment technology, and in particular to a sewage treatment device. Background Art
[0002] In existing aerobic processes such as AO, A2O, MBR, and MBBR, a blower is usually used to connect a microporous aerator to aerate the aerobic tank. Under the optimal water depth of 4-6 meters, the oxygen utilization rate is 19~27%, and most of the microporous bubbles escape back into the air without being completely dissolved.
[0003] In small-scale integrated domestic sewage treatment processes or systems, the water depth of the aerobic pool is less than 2 meters. At the same water temperature, the reduced water depth leads to a decrease in oxygen utilization, which drops to about 10%. This results in additional aeration energy consumption at the aerobic end to maintain dissolved oxygen at 2-4 mg / L.
[0004] In addition, the internal reflow water at the outlet of the aerobic pool has a very short return journey into the denitrification pool and a high dissolved oxygen content. The denitrification pool can only operate under anaerobic conditions (dissolved oxygen ≤ 0.5 mg / L). When the nitrification reflow is relatively high, it is easy to cause the dissolved oxygen concentration in the denitrification pool to rise, and it is difficult to control the anaerobic environment, thereby affecting the removal efficiency of total nitrogen in the denitrification process.
[0005] In addition, the pores of the microporous aerator are prone to clogging as the running time accumulates, and need to be cleaned, maintained or replaced regularly. Utility Model Content
[0006] In order to solve the problem of low oxygen utilization and blockage caused by long-term aeration mentioned in the background technology, the present application provides a sewage treatment device, which uses a rotary biofilter to improve oxygen utilization and fundamentally avoids the blockage problem. The above-mentioned purpose of the present application is achieved through the following technical solutions:
[0007] The present application provides a sewage treatment device, comprising:
[0008] A denitrification tank, a rotary biofilter and a conveying member, wherein the conveying member is used to convey the water in the denitrification tank to the rotary biofilter;
[0009] A diverter and a precipitator, wherein the diverter is connected to an output end of the rotary biofilter, the diverter has two output ends, a first output end of the diverter is connected to a denitrification tank, and a second output end of the diverter is connected to a precipitator;
[0010] The rotary biofilter comprises: a shell;
[0011] A rotating shaft is disposed on the housing and is rotatably connected to the housing; a plurality of carrier discs are disposed on the rotating shaft at intervals;
[0012] Wherein, a portion of the carrier disc is located below the liquid level in the shell.
[0013] In a possible implementation of the present application, a delivery pump is further included in the regulating tank, and an output end of the delivery pump is located in the denitrification tank;
[0014] An ejector is arranged on the output end of the delivery pump, and the ejector is used to drive the water in the denitrification tank to circulate.
[0015] In a possible implementation of the present application, the ejector has multiple output ends, and the multiple output ends of the ejector face different directions respectively.
[0016] In a possible implementation of the present application, the carrier disc includes a disc and carriers uniformly distributed on the disc.
[0017] In a possible implementation of the present application, the number of the rotary biofilters is one or more, and the connection modes of the rotary biofilters include series connection and parallel connection.
[0018] In a possible implementation of the present application, the rotary biofilter is also connected to a denitrification tank and a precipitator.
[0019] In a possible implementation of the present application, a primary sedimentation tank and a regulating tank are provided before the denitrification tank.
[0020] The beneficial effects of this application are:
[0021] The present application provides a sewage treatment device which uses a rotary biofilter to improve oxygen utilization. A portion of the rotary biofilter is located inside the water body and a portion is located outside the water body. During the treatment process, the biofilter rotates continuously so that the biofilm attached to the biofilter can be directly exposed to the air. This method can effectively improve oxygen utilization, while ensuring the treatment speed and avoiding the blockage problem that is prone to occur in pipeline aeration. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a structural schematic diagram of a sewage treatment device provided in this application.
[0023] Figure 2 It is a schematic diagram of the working principle of an ejector provided in this application.
[0024] Figure 3 It is a three-dimensional structural schematic diagram of a rotary biological filter provided in the present application.
[0025] Figure 4 This is a schematic diagram of a plurality of rotary biofilters connected in series provided by the present application.
[0026] Figure 5 It is a structural schematic diagram of a carrier disc provided in this application.
[0027] In the figure, 1. conveying member, 2. rotary biofilter, 3. precipitator, 4. diverter, 10. sedimentation tank, 11. regulating tank, 12. denitrification tank, 13. conveying pump, 14. ejector, 21. shell, 22. rotating shaft, 23. carrier disc, 231. disc, 232. carrier. DETAILED DESCRIPTION
[0028] The technical solution in this application is further described in detail below in conjunction with the accompanying drawings.
[0029] This application discloses a sewage treatment device, see Figure 1 In some examples, the sewage treatment device disclosed in the present application includes a primary sedimentation tank 10, a regulating tank 11 and a denitrification tank 12, a conveying member 1, a rotary biofilter 2, a precipitator 3 and a diverter 4, and the primary sedimentation tank 10, the regulating tank 11 and the denitrification tank 12 are connected in sequence.
[0030] The primary sedimentation tank 10 is used to pre-treat the water body to be treated, mainly to remove suspended solids in the water body.
[0031] The function of the regulating tank 11 is to regulate the water quality of the pretreated water body. The reason for water quality regulation is that domestic sewage usually has three peak water use periods in the morning, noon and evening. The regulating tank can store peak water. Generally, the hydraulic retention time is at least 12 hours to ensure that the peak water and the trough water are fully mixed to achieve average and average volume, so that the sewage concentration entering the denitrification tank 12 is stable, reducing the impact and influence on subsequent treatment processes.
[0032] The denitrification tank 12 is used to re-treat the water treated by the primary sedimentation tank 10, with the purpose of removing ammonia nitrogen and other pollutants in the wastewater.
[0033] In some examples, a grid is placed on the primary sedimentation tank 10, and the grid is used to intercept garbage, and the intercepted garbage is sent to a garbage treatment station for treatment.
[0034] In some examples, the water in the regulating tank 11 is transported using a delivery pump 13 , the main body of the delivery pump 13 is located at the bottom of the regulating tank 11 , and the output end of the delivery pump 13 is located in the denitrification tank 12 .
[0035] See also Figure 1 and Figure 2 In some possible implementations, an ejector 14 may be added to the output end of the delivery pump 13 , and the ejector 14 is used to drive the water in the denitrification tank 12 to circulate. Figure 2 The dotted line in is the flow trajectory of the water body. Figure 1 The above contents are further explained as follows: the horizontal lines and wavy lines inside the rotary biofilter 2 indicate the water level, the horizontal lines inside the sedimentator 3 indicate the water level, the symmetrical triangles arranged in the pipeline indicate valves for controlling the opening and closing of the pipeline, and the arrows inside the denitrification tank 12 indicate the direction of water flow.
[0036] for Figure 1 The above contents are further explained as follows: the horizontal lines and wavy lines inside the rotary biofilter 2 indicate the water level, the horizontal lines inside the sedimentator 3 indicate the water level, the symmetrical triangles arranged in the pipeline indicate valves for controlling the opening and closing of the pipeline, and the arrows inside the denitrification tank 12 indicate the direction of water flow.
[0037] In some implementations, the ejector 14 has multiple output ends, and the multiple output ends of the ejector 14 face different directions respectively.
[0038] The function of the conveying member 1 is to convey the water in the denitrification tank 12 into the rotary biofilter 2. The conveying member 1 can be a pump or a pipe. When the conveying member 1 uses a pipe, the water in the denitrification tank 12 flows into the rotary biofilter 2 by gravity.
[0039] The diverter 4 is connected to the output end of the rotary biofilter 2. The diverter 4 has two output ends. The first output end of the diverter 4 is connected to the denitrification tank 12, and the second output end of the diverter 4 is connected to the precipitator 3. The water filtered by the precipitator 3 flows out of the precipitator 3.
[0040] The water entering the denitrification tank 12 carries sufficient carbon sources and is mixed with the water flowing out of the rotary biofilter 2 and the returned sludge. This process mainly removes nitrogen in the water through denitrifying bacteria.
[0041] The returned sludge has two sources. The first is the sludge generated during the operation of the rotary biofilter 2, and the second is the sludge generated during the subsequent treatment process. The subsequent treatment process is further introduced in the following content.
[0042] For some examples, see Figure 3 and Figure 4 The rotary biofilter 2 includes a shell 21, a rotating shaft 22 and a carrier disc 23. The rotating shaft 22 is installed on the shell 21. The connection between the two is a rotational connection. The carrier disc 23 is fixedly installed on the rotating shaft 22 and is located inside the shell 21.
[0043] One function of the rotating shaft 22 is to drive the carrier disc 23 to rotate at a fixed speed. The power source of the rotating shaft 22 can be a motor. The motor is deployed outside the housing 21 and connected to the rotating shaft 22 using a connecting piece such as a coupling.
[0044] The aerobic microorganisms on the carrier disc 23 continuously grow and multiply by absorbing organic matter and ammonia nitrogen in the sewage, and gradually form a layer of biofilm on the carrier disc 23 .
[0045] About 40% of the volume of the carrier disc 23 is immersed in water, and the dissolved oxygen in the water is increased during the continuous rotation process, providing the necessary oxygen for the growth of aerobic microorganisms, thereby reciprocatingly purifying pollutants.
[0046] In some examples, the rotary biofilter 2 is modularly designed, and a single unit has a treatment flow rate of 50 m³ / d. The rotary biofilters can be connected in series or in parallel to form different treatment scales according to the number of devices matched to the pollution load of domestic sewage.
[0047] See also Figure 5 The carrier disc 23 includes a disc 231 and carriers 232 evenly distributed on the disc 231. One function of the carrier 232 is to increase the surface area of the disc 231, and the other function is to provide a basis for the attachment of aerobic microorganisms.
[0048] It should also be understood that the sludge at the bottom of the primary settling tank 10 is regularly discharged using a sludge pump.
[0049] The precipitator 3 uses an inclined plate precipitator, in which a plurality of inclined inclined plates are arranged. The sludge produced by filtration is precipitated to the bottom of the inclined plate precipitator, and the liquid produced by filtration is transported through a pipeline.
[0050] Furthermore, according to some specific domestic sewage treatment implementation cases, for example, the treatment flow rate is 20m³ / d, the system influent pollution concentration is COD≤200mg / L, ammonia nitrogen≤35mg / L, total nitrogen≤35mg / L, and suspended solids≤150mg / L.
[0051] The number of rotary biofilters 2 used is 1, and the removal rate of suspended solids in the primary sedimentation tank 10 is 30-50%, and the removal rates of COD, ammonia nitrogen and TN are 10-20% on average.
[0052] The average carbon-nitrogen ratio of the influent of denitrification pool 12 is 5.5 (in terms of TN), which is preliminarily judged to meet the carbon source required for denitrification. According to the influence curve of water temperature and reflux ratio on denitrification, by adjusting the reflux ratio and maintaining it at 2 times reflux, when the water temperature is greater than 20°C, the total nitrogen removal rate is 40%~50%, which meets the total nitrogen concentration of ≤20mg / L and reaches the urban standard level B. When the reflux ratio is adjusted and maintained at 3 times reflux, the total nitrogen removal rate is 50%~60%, which meets the total nitrogen concentration of ≤15mg / L and reaches the urban standard level A.
[0053] The denitrification process simultaneously consumes a certain amount of carbon source. In actual operation, the COD removal rate of the denitrification pool 12 is 55%~65%, the average COD concentration of the denitrification pool inlet is ≤170mg / L, and the average COD concentration of the effluent is ≤70mg / L.
[0054] The COD concentration in the influent of the rotary biofilter 2 is ≤70mg / L, the ammonia nitrogen is ≤15mg / L, the organic area load is 5~10g COD / ㎡`d, and the ammonia nitrogen load is 1.0~2.0g NH3-N / ㎡`d. The removal rate of the rotary biofilter 2 for COD is 50%~60%, and the removal rate for ammonia nitrogen is 80%~85%.
[0055] Inclined plate sedimentation has almost no removal rate for ammonia nitrogen and total nitrogen, and has a small removal rate for COD, which is 5%~15%. Inclined plate sedimentation mainly removes suspended residual sludge, and has a good removal rate for suspended solids, which is about 50%~60%. The SS concentration of the inlet water of the inclined plate sedimentation is 20~40mg / L, and the SS concentration of the outlet water is 10~20mg / L, and the suspended solids concentration reaches Class I B.
[0056] The embodiments of this specific implementation method are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore, all equivalent changes made based on the structure, shape, and principle of the present application should be included in the protection scope of the present application.
Claims
1. A sewage treatment device, characterized in that: include: A denitrification tank (12), a rotary biological filter (2) and a conveying member (1), wherein the conveying member (1) is used to convey water in the denitrification tank (12) to the rotary biological filter (2); A flow divider (4) and a sedimentation tank (3), wherein the flow divider (4) is connected to an output end of the rotary biofilter (2), and the flow divider (4) has two output ends, wherein a first output end of the flow divider (4) is connected to a denitrification tank (12), and a second output end of the flow divider (4) is connected to the sedimentation tank (3); The rotary biofilter (2) comprises: Housing (21); A rotating shaft (22) is disposed on the housing (21) and is rotatably connected to the housing (21); A plurality of carrier discs (23) are arranged on the rotating shaft (22) at intervals; Part of the carrier disc (23) is located below the liquid level in the housing (21).
2. The sewage treatment device according to claim 1, characterized in that: The carrier disc (23) comprises a disc (231) and carriers (232) evenly distributed on the disc (231).
3. The sewage treatment device according to claim 1 or 2, characterized in that: The number of the rotary biofilters (2) is one or more, and the connection modes of the rotary biofilters (2) include series connection and parallel connection.
4. The sewage treatment device according to claim 1, characterized in that: It also includes a delivery pump (13) disposed in the regulating tank (11), wherein the output end of the delivery pump (13) is located in the denitrification tank (12); An ejector (14) is provided at the output end of the delivery pump (13), and the ejector (14) is used to drive the water in the denitrification tank (12) to circulate.
5. The sewage treatment device according to claim 4, characterized in that: The ejector (14) has a plurality of output ends, and the plurality of output ends of the ejector (14) face in different directions respectively.
6. The sewage treatment device according to claim 1, characterized in that: The rotary biofilter (2) is also connected to the denitrification tank (12) and the precipitator (3).
7. The sewage treatment device according to claim 1, characterized in that: A primary sedimentation tank (10) and a regulating tank (11) are provided before the denitrification tank (12).