Adjustable low-temperature sewage treatment device suitable for plateau cold region

Abstract

The invention discloses an adjustable low-temperature sewage treatment device applicable to plateau cold regions, which belongs to the technical field of sewage treatment and comprises a water inlet system, a biochemical treatment system and an automatic adjusting system. The water inlet system comprises a water inlet adjusting tank and a water inlet pump; the biochemical treatment system is of a funnel-shaped structure and comprises an anoxic zone, an anaerobic zone, an aerobic zone and a settling zone, one end of the water inlet pump is connected with the water inlet regulating tank, and the other end of the water inlet pump is connected with the top of the anoxic zone; a mixer is arranged in the anaerobic zone, and a stirrer and an aeration disc are arranged in the aerobic zone; the automatic adjusting system comprises an ammonia nitrogen online detector, a temperature online detector and a precise aeration system. The automatic regulating system can regulate and control the DO value and the aeration time in real time according to the water quality and temperature change, so that the sewage treatment cost and the sewage treatment capacity are greatly reduced; meanwhile, the influence of water quality and temperature fluctuation in the plateau cold region on the sewage nitrogen removal performance is effectively solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of sewage treatment, and particularly relates to an adjustable low-temperature sewage treatment device applicable to high-altitude cold regions. Background Art

[0002] The AAO process is widely used in sewage treatment due to its good nitrogen and phosphorus removal efficiency. However, since activated sludge is extremely sensitive to temperature, it makes the AAO process difficult to operate stably in alpine and high-altitude regions.

[0003] Due to geographical location differences, the water temperature in alpine and high-altitude regions is relatively low, with an annual average water temperature between 10 and 15 °C, and the water temperature will further drop to 4 °C in winter. It is reported that the most suitable operating temperature of the AAO process is between 25 and 35 °C. If the temperature drops to 15 °C, it will cause a significant decline in the nitrogen removal performance of the AAO process. Compared with 25 °C, the removal rates of ammonia nitrogen and total nitrogen by the AAO process at 15 °C decrease by 15% and 45% respectively. When the temperature is below 10 °C, the nitrification rate and denitrification rate of the AAO process will decrease by more than 30% and 70%. When the temperature drops to 4 - 5 °C, the AAO process loses its nitrification and denitrification functions.

[0004] Although some scholars have ensured the stable operation of the AAO process at low temperatures by adding microbial agents or fillers, etc., it can only ensure the stable operation of the system for a short period of time. At the same time, this also greatly increases the sewage treatment cost in the region. Therefore, aiming at the deficiencies of the AAO process in alpine and high-altitude regions, it is urgent to develop a new type of low-temperature resistant sewage treatment process.

[0005] In addition, the traditional AAO process often adopts a reflux method to achieve nitrogen removal, which requires the additional construction of an anaerobic tank and an anoxic tank to achieve denitrification and nitrogen removal, which greatly increases the construction and operation costs of the sewage treatment plant. Therefore, if an internal reflux method can be adopted for nitrogen removal, the sewage treatment cost can be reduced. Based on the deficiencies of the existing process, there is an urgent need to develop a sewage treatment device with a small footprint, strong low-temperature resistance, low treatment cost, and capable of automatically adjusting according to regional environment and water quality changes to meet the sewage treatment in alpine and high-altitude regions. Summary of the Invention

[0006] Aiming at the challenges faced by the AAO process in alpine and high-altitude regions, the purpose of the present invention is to innovatively develop a sewage treatment device with a small footprint, strong low-temperature resistance, low treatment cost, and capable of automatically adjusting according to regional environment and water quality changes.

[0007] The purpose of the present invention is achieved through the following technical solutions: An adjustable low-temperature sewage treatment device applicable to high-altitude cold regions, comprising an inlet water system, a biochemical treatment system, and an automatic adjustment system; The water inlet system includes a water inlet regulating tank and a water inlet pump; The biochemical treatment system is of a funnel-shaped structure. The biochemical treatment system includes an anoxic zone, an anaerobic zone, an aerobic zone, and a sedimentation zone. The aerobic zone and the anaerobic zone are arranged vertically and on one side of the anoxic zone. The sedimentation zone is on the other side of the aerobic zone and is in a funnel shape. The bottom of the anoxic zone communicates with the anaerobic zone, the bottom of the aerobic zone communicates with the sedimentation zone, the anoxic zone, the aerobic zone, and the sedimentation zone are arranged adjacent to each other. A first one-way baffle from the aerobic zone to the anoxic zone is provided between the tops of the aerobic zone and the anoxic zone. A second one-way baffle from the aerobic zone to the sedimentation zone is provided between the tops of the aerobic zone and the sedimentation zone. An outlet pipe is provided on the side of the top of the sedimentation zone away from the aerobic zone; One end of the water inlet pump is connected to the water inlet regulating tank, and the other end of the water inlet pump is connected to the top of the anoxic zone; A mixer is arranged in the anaerobic zone, and a stirrer and an aeration disc are arranged in the aerobic zone; The automatic regulation system includes an ammonia nitrogen on-line detector, a temperature on-line detector, and a precise aeration system. The precise aeration system includes a DO on-line detector, a variable-frequency aeration fan, a rotameter, a vortex flowmeter, and a micro-pressure relief system. The detection heads of the ammonia nitrogen on-line detector, the temperature on-line detector, and the DO on-line detector are located in the aerobic zone. The output ends of the ammonia nitrogen on-line detector and the temperature on-line detector are electrically connected to the DO on-line detector. The output end of the DO on-line detector is connected to the variable-frequency aeration fan, and the other end of the variable-frequency aeration fan is connected to the aeration disc.

[0008] Further, the stirrer is located above the aeration disc, and an aeration pump is provided between the variable-frequency aeration fan and the aeration disc.

[0009] Further, the rotameter, the vortex flowmeter, and the micro-pressure relief system are located on the pipeline between the aeration disc and the variable-frequency aeration fan.

[0010] Further, an inclined first baffle is provided at the bottom of the anoxic zone, and inclined second baffles are provided at the top and bottom of the sedimentation zone.

[0011] Further, sludge discharge ports are provided at the bottoms of the anoxic zone and the sedimentation zone.

[0012] Further, the stirring rate of the stirrer is controlled at 60 - 70 rpm / min.

[0013] Further, the sludge concentration in the biochemical tank is controlled between 3000 - 3500 mg / L.

[0014] Furthermore, the DO concentration in the biochemical pool was controlled between 4 and 7 mg / L according to the influent ammonia nitrogen concentration and water temperature, and the aeration time was controlled between 2.5 and 4 h.

[0015] Furthermore, the operating frequency of the variable frequency aeration fan is controlled at 30~50 Hz.

[0016] The beneficial effects of the present invention are: 1) The device has dual denitrification capabilities at low temperatures, that is, it can remove nitrogen through denitrification in the anoxic zone and through heterotrophic nitrification-aerobic denitrification in the aerobic zone.

[0017] 2) The automatic adjustment system can adjust the DO value and aeration time in real time according to changes in water quality and temperature, thereby greatly reducing sewage treatment costs and increasing sewage treatment capacity.

[0018] 3) The automatic adjustment system can not only greatly improve the nitrogen removal efficiency, but also effectively solve the impact of water quality and temperature fluctuations in plateau cold areas on sewage nitrogen removal performance.

[0019] 4) Precise control of the DO value in the aerobic zone can not only ensure the stable growth of nitrifying and denitrifying bacteria under low temperature, but also enhance the sedimentation performance of sludge, thus overcoming the problem of sludge expansion caused by low temperature.

[0020] 5) Controlling DO through the automatic adjustment system can promote the enrichment of nitrifying bacteria and denitrifying bacteria in the sludge at low temperature (4°C), thereby ensuring that the nitrogen in the sewage meets the discharge standards. In sewage treatment, there is no need to add chemicals to ensure that the total nitrogen in the effluent meets the discharge standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of an adjustable low-temperature sewage treatment device suitable for plateau cold regions according to the present invention, wherein the solid arrows indicate the direction of water flow, and the dotted arrows indicate the direction of electrical signals or aeration; Figure 2 It is a graph showing the change in the total relative abundance of nitrifying bacteria and denitrifying bacteria in the sludge after adjustment by the automatic adjustment system in the present invention; Figure 3 This is a graph showing the relative abundance change of heterotrophic nitrification-aerobic denitrification bacteria (Flavobacterium) in sludge after adjustment by the automatic adjustment system in the present invention; Figure 4 This is a graph showing the concentration change of ammonia nitrogen after adjustment by the automatic adjustment system in the present invention; In the figure, 11 is the influent regulation tank, 12 is the influent pump, 3 is the anoxic zone, 31 is the first baffle, 32 is the sludge discharge port, 4 is the anaerobic zone, 41 is the mixer, 5 is the aerobic zone, 51 is the stirrer, 52 is the aeration disk, 53 is the first one-way baffle, 6 is the sedimentation zone, 61 is the second one-way baffle, 62 is the outlet pipe, 63 is the second baffle, 7 is the ammonia nitrogen on-line detector, 8 is the temperature on-line detector, 91 is the DO on-line detector, 92 is the variable-frequency aeration fan, 93 is the aeration pump, and 94 is the micro pressure relief system. Detailed implementation manners

[0022] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present invention.

[0023] Refer to Figure 1 , the present invention provides an adjustable low-temperature sewage treatment device applicable to high-altitude cold regions, including an influent system, a biochemical treatment system, and an automatic regulation system; The influent system includes an influent regulation tank 11 and an influent pump 12; wherein the influent regulation tank 11 can store and regulate the amount of sludge water entering the treatment system to ensure that the subsequent biochemical treatment system can operate under a stable flow rate. When the influent flow rate is uneven, the regulation tank can buffer the change of water volume to prevent the treatment equipment from being unable to work properly due to flow fluctuations. At the same time, the influent regulation tank 11 can mix the sludge water at different times or from different sources to make the outflow water quality more uniform and reduce the impact of water quality fluctuations on the biochemical treatment system.

[0024] The biochemical treatment system is of a funnel-shaped structure. The biochemical treatment system includes an anoxic zone 3, an anaerobic zone 4, an aerobic zone 5, and a sedimentation zone 6. The aerobic zone 5 and the anaerobic zone 4 are arranged up and down and are located on one side of the anoxic zone 3. The sedimentation zone 6 is located on the other side of the aerobic zone 5 and is in a funnel shape. The bottom of the anoxic zone 3 is communicated with the anaerobic zone 4, the bottom of the aerobic zone 5 is communicated with the sedimentation zone 6, the anoxic zone 3, the aerobic zone 5, and the sedimentation zone 6 are arranged adjacent to each other. A second one-way baffle 61 from the aerobic zone 5 to the sedimentation zone 6 is provided between the tops of the aerobic zone 5 and the sedimentation zone 6, and an outlet pipe 62 is provided on one side of the top of the sedimentation zone 6 away from the aerobic zone 5.

[0025] Through the above technical solution, one end of the influent pump 12 is connected to the influent regulation tank 11, and the other end of the influent pump 12 is connected to the top of the anoxic zone 3. And the direct connection of the influent to the anoxic zone 3 can provide sufficient carbon source for the growth of denitrifying bacteria, thereby strengthening the reduction ability of nitrate.

[0026] Meanwhile, the water flow sequentially passes through the anoxic zone 3, the anaerobic zone 4, the aerobic zone 5, and the sedimentation zone 6, and finally discharges from the outlet pipe 62. The use of the internal circulation method for denitrification can ensure the synchronous progress of nitrification-denitrification reaction, eliminating the need to separately construct anoxic and anaerobic ponds.

[0027] Taking the AAO process adopted in this solution as an example, the anoxic zone 3, the anaerobic zone 4, and the aerobic zone 5 form a complete biological nitrogen and phosphorus removal system. In the anoxic zone 3, denitrification and nitrogen removal occur; in the anaerobic zone 4, phosphorus is released and part of the organic matter is decomposed; in the aerobic zone 5, nitrification and phosphorus absorption take place. Through the synergistic effect of these three zones, the AAO process can effectively remove BOD, nitrogen, and phosphorus in sewage, and is applicable to sewage treatment occasions with strict requirements for nitrogen and phosphorus removal.

[0028] Specifically, the main function of the anoxic zone 3 is to carry out the denitrification reaction and remove nitrate in the sewage. Under anoxic conditions, denitrifying bacteria use the organic matter in the sewage as a carbon source to reduce nitrate to nitrogen gas, thereby removing nitrate. In addition, the anoxic zone 3 can also remove part of the organic matter and ammonia nitrogen, solving the problem of high organic nitrogen concentration in the influent in plateau areas.

[0029] The functions of the aerobic zone 5 include nitrification, denitrification, phosphorus absorption, and further removal of organic matter. Under aerobic conditions, nitrifying bacteria oxidize ammonia nitrogen to nitrate nitrogen. Aerobic denitrifying bacteria and heterotrophic nitrification-aerobic denitrifying bacteria can convert ammonia nitrogen or nitrate nitrogen into nitrogen gas. Polyphosphate-accumulating organisms use the carbon source in the cells to absorb phosphate and remove phosphorus by discharging excess sludge. The aerobic zone 5 can also further degrade organic matter.

[0030] The functions of the aerobic zone 5 include nitrification, phosphorus absorption, and further removal of organic matter. Under aerobic conditions, nitrifying bacteria oxidize ammonia nitrogen to nitrate nitrogen. Polyphosphate-accumulating organisms use the carbon source in the cells to absorb phosphate and remove phosphorus by discharging excess sludge. The aerobic zone 5 can also further degrade organic matter.

[0031] The main function of the sedimentation zone 6 is to separate mud and water. The mixed liquid after biological treatment enters the sedimentation zone 6, and through the action of gravity, the sludge and water are separated, thus realizing the separation of mud and water. The setting of the sedimentation zone 6 helps to improve the effluent quality and reduce the sludge discharge.

[0032] Furthermore, the anaerobic zone 4 is set at the bottom of the aerobic zone 5 to strengthen the hydrolysis ability of anaerobic microorganisms for refractory organic matter (such as proteins, polysaccharides, etc.), ensuring that microorganisms can store the hydrolyzed carbon source in the cells and providing an internal carbon source for subsequent denitrification.

[0033] Furthermore, a first one-way baffle 53 from the aerobic zone 5 to the anoxic zone 3 is provided between the tops of the aerobic zone 5 and the anoxic zone 3. After the reaction in the aerobic zone 5 ends, part of the sewage can directly flow back to the anoxic zone 3 through the first one-way baffle 53 for denitrification reaction, ensuring the up-to-standard discharge of total nitrogen.

[0034] Furthermore, a second one-way baffle 61 from the aerobic zone 5 to the sedimentation zone 6 is provided between the tops of the aerobic zone 5 and the sedimentation zone 6. When the sewage that cannot be treated in the aerobic zone 5 can enter the sedimentation zone 6 through the second one-way baffle 61.

[0035] A mixer 41 is provided in the anaerobic zone 4, and a stirrer 51 and an aeration disc 52 are provided in the aerobic zone 5; Among them, the mixer 41 is provided in the anaerobic zone 4, aiming to enhance the hydrolysis and acidification ability of microorganisms to organic matter. On the one hand, it provides a carbon source for the growth of microorganisms in the aerobic zone 5. On the other hand, it ensures that part of the hydrolyzed carbon source can be stored in the cells by microorganisms to form an internal carbon source, providing an internal carbon source for the denitrification in the anoxic zone 3. The stirrer 51 provided in the aerobic zone 5 can promote the mixing of water flow and bubbles, increase the contact area and time between bubbles and liquid, thereby improving the oxygen transfer efficiency. This helps to more effectively transfer the oxygen in the air to the sewage in the aeration tank to meet the respiratory needs of microorganisms. At the same time, the core role of the aeration disc 52 is to increase the dissolved oxygen content in the water body, promote the biodegradation process, and improve the water quality environment.

[0036] Furthermore, the automatic regulation system includes an ammonia nitrogen on-line detector 7, a temperature on-line detector 8 and a precise aeration system. The precise aeration system includes a DO on-line detector 91, a variable-frequency aeration fan 92, a rotameter, a vortex flowmeter and a micro-pressure relief system 94. The detection heads of the ammonia nitrogen on-line detector 7, the temperature on-line detector 8 and the DO on-line detector 91 are located in the aerobic zone 5. The output ends of the ammonia nitrogen on-line detector 7 and the temperature on-line detector 8 are electrically connected to the DO on-line detector 91. The output end of the DO on-line detector 91 is connected to the variable-frequency aeration fan 92, and the other end of the variable-frequency aeration fan 92 is connected to the aeration disc 52.

[0037] Through the above technical solutions, the automatic regulation system automatically regulates the DO value and aeration time according to the changes in the ammonia nitrogen concentration and water temperature in the aerobic zone 5. At the same time, the variable-frequency aeration fan 92 and the aeration disc 52 can achieve intermittent aeration and variable-frequency aeration according to the DO value feedback by the automatic regulation system.

[0038] The automatic regulation system can greatly enhance the system's resistance to water quality and temperature impacts, ensuring that the system can still operate stably at 4°C. Controlling the DO value through the automatic regulation system can promote the enrichment of heterotrophic nitrification-aerobic denitrification bacteria (HN-AD), and synchronous nitrification and denitrification reactions can be achieved in the aerobic zone 5.

[0039] Combining the automatic regulation system and the aeration device can enhance the hydraulic impact force on the sludge, effectively achieve the screening of microorganisms, and thus form heavy sludge resistant to low temperatures.

[0040] Furthermore, the stirrer 51 is located above the aeration disc 52, and an aeration pump 93 is provided between the variable-frequency aeration blower 92 and the aeration disc 52.

[0041] Through the above technical solution, the variable-frequency aeration blower 92 and the aeration pump 93 compress oxygen into fine bubbles and input them into the water in the aerobic zone 5 through the aeration disc 52, directly increasing the contact area between oxygen and water, thereby increasing the dissolved oxygen content. Among them, the stirrer 51 starts to operate during the aeration stage. On the one hand, it can promote the aggregation of microorganisms and enhance the tolerance of microorganisms to low-temperature environments; on the other hand, it can enhance the ability of material and electron transfer between microorganisms, thereby promoting the enrichment of nitrifying bacteria.

[0042] Furthermore, the rotameter, vortex flowmeter, and micro-pressure relief system 94 are located on the pipeline between the aeration disc 52 and the variable-frequency aeration blower 92.

[0043] Through the above technical solution, the micro-pressure relief system 94 can automatically exhaust gas according to the feedback data of the rotameter and the vortex flowmeter, avoiding large fluctuations in the DO value.

[0044] Furthermore, an inclined first baffle 31 is provided at the bottom of the anoxic zone 3, and inclined second baffles 63 are provided at the top and bottom of the sedimentation zone 6.

[0045] Through the above technical solution, an inclined first baffle 31 is provided at the bottom of the anoxic zone 3, so that the water flowing out from the bottom of the anoxic zone 3 enters the anaerobic zone 4, and the sludge can be blocked by the first baffle 31; while the inclined second baffles 63 provided at the top and bottom of the sedimentation zone 6 facilitate the sedimentation of sludge.

[0046] Furthermore, sludge discharge ports 32 are provided at the bottom of the anoxic zone 3 and the bottom of the sedimentation zone 6.

[0047] Through the above technical solution, setting the sludge discharge ports 32 can facilitate sludge discharge, avoid the formation of dead sludge areas and blockages, and the sludge discharge ports 32 are provided with on-off valves for opening and closing.

[0048] Furthermore, the stirring rate of the stirrer 51 is controlled at 60 - 70 rpm / min to keep the rotation speed appropriate and avoid over-stirring or under-stirring.

[0049] Furthermore, the sludge concentration in the influent regulation tank 11 is controlled between 3000 and 3500 mg / L to avoid excessive concentration affecting subsequent sewage treatment.

[0050] Furthermore, the operating frequency of the variable-frequency aeration fan is controlled between 30 and 50 Hz.

[0051] Preferably, the automatic regulation system according to the changes of ammonia nitrogen and temperature needs to control the DO value and reaction time in the aerobic zone 5 between 4 and 7 and between 2.5 and 4 h respectively.

[0052] As Figure 2 shown, after being regulated by the automatic regulation system, the total relative abundances of nitrifying bacteria and denitrifying bacteria in the sludge increased by 95.33% and 66.07% respectively.

[0053] As Figure 3 shown, after being regulated by the automatic regulation system, the relative abundance of heterotrophic nitrification-aerobic denitrifying bacteria (Flavobacterium) in the sludge increased by 231.58%.

[0054] As Figure 4 shown, after being regulated by the automatic regulation system, the ammonia nitrogen removal rate increased by 64.36%.

[0055] The above are only the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be changed within the scope of the concept described herein through the above teachings or the technology or knowledge in related fields. And the changes and alterations made by those skilled in the art without departing from the spirit and scope of the present invention shall fall within the protection scope of the appended claims of the present invention.

Claims

1. An adjustable low-temperature sewage treatment device suitable for plateau cold areas, characterized by: Including water intake system, biochemical treatment system and automatic adjustment system; The water inlet system comprises a water inlet regulating tank (11) and a water inlet pump (12); The biochemical treatment system is a funnel-shaped structure, comprising an anoxic zone (3), an anaerobic zone (4), an aerobic zone (5) and a sedimentation zone (6), wherein the aerobic zone (5) and the anaerobic zone (4) are arranged vertically and located on one side of the anoxic zone (3), and the sedimentation zone (6) is located on the other side of the aerobic zone (5) and is in a funnel shape, wherein the bottom of the anoxic zone (3) is connected to the anaerobic zone (4), and the bottom of the aerobic zone (5) is connected to the sedimentation zone (6). The anoxic zone (3), the aerobic zone (5) and the sedimentation zone (6) are arranged adjacent to each other; a first one-way baffle plate (53) from the aerobic zone (5) to the anoxic zone (3) is provided between the tops of the aerobic zone (5) and the anoxic zone (3); a second one-way baffle plate (61) from the aerobic zone (5) to the sedimentation zone (6) is provided between the tops of the aerobic zone (5) and the sedimentation zone (6); and a water outlet pipe (62) is provided on a side of the top of the sedimentation zone (6) away from the aerobic zone (5); One end of the water inlet pump (12) is connected to the water inlet regulating tank (11), and the other end of the water inlet pump (12) is connected to the top of the anoxic zone (3); The anaerobic zone (4) is provided with a mixer (41), and the aerobic zone (5) is provided with a stirrer (51) and an aeration plate (52); The automatic adjustment system comprises an online ammonia nitrogen detector (7), an online temperature detector (8) and a precision aeration system. The precision aeration system comprises an online DO detector (91), a variable frequency aeration fan (92), a rotor flowmeter, a vortex flowmeter and a micro pressure relief system (94). The detection heads of the online ammonia nitrogen detector (7), the online temperature detector (8) and the online DO detector (91) are located in the aerobic zone (5). The output ends of the online ammonia nitrogen detector (7) and the online temperature detector (8) are electrically connected to the online DO detector (91). The output end of the online DO detector (91) is connected to the variable frequency aeration fan (92). The other end of the variable frequency aeration fan (92) is connected to the aeration disk (52).

2. The adjustable low-temperature sewage treatment device suitable for plateau cold regions according to claim 1 is characterized by: The stirrer (51) is located above the aeration plate (52), and an aeration pump (93) is provided between the variable frequency aeration fan (92) and the aeration plate (52).

3. The adjustable low-temperature sewage treatment device suitable for plateau cold regions according to claim 1 is characterized by: The rotor flowmeter, vortex flowmeter and micro-pressure relief system (94) are located on the pipeline between the aeration disk (52) and the variable frequency aeration fan (92).

4. The adjustable low-temperature sewage treatment device suitable for plateau cold regions according to claim 1 is characterized by: The bottom of the anoxic zone (3) is provided with an inclined first baffle (31), and the top and bottom of the precipitation zone (6) are provided with inclined second baffles (63).

5. The adjustable low-temperature sewage treatment device suitable for plateau cold regions according to claim 1 is characterized by: Mud discharge ports (32) are provided at the bottom of the anoxic zone (3) and the bottom of the sedimentation zone (6).

6. The adjustable low-temperature sewage treatment device suitable for plateau cold regions according to claim 1 is characterized by: The stirring speed of the stirrer (51) is controlled at 60-70 rpm / min.

7. The adjustable low-temperature sewage treatment device suitable for plateau cold regions according to claim 1 is characterized by: The sludge concentration in the inlet regulating tank (11) is controlled between 3000 and 3500 mg / L.

8. The adjustable low-temperature sewage treatment device suitable for plateau cold regions according to claim 1 is characterized by: The operating frequency of the variable frequency aeration fan (92) is controlled at 30-50 Hz.

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