Aerobic reactor and wastewater treatment method for wastewater treatment

Abstract

This invention provides an aerobic reactor for wastewater treatment, comprising a tank, a sludge-water separation device disposed at the upper and lower parts of the tank, and at least one set of hydraulic mixing and oxygen supply devices. A clear liquid outlet is provided at the top of the side wall of the tank. The hydraulic mixing and oxygen supply device includes a liquid distributor and several upward-spraying and downward-spraying hydraulic agitators evenly distributed on both sides of the tank, with the number of upward-spraying hydraulic agitators not less than the number of downward-spraying hydraulic agitators. The inlet and outlet of the liquid distributor are respectively connected to the wastewater source and the hydraulic agitators. The sludge-water separation device includes a sludge-water separation module and a horizontal annular baffle sandwiched between the upper outer part of the sludge-water separation module and the inner side wall of the tank. The horizontal annular baffle is located below the clear liquid outlet. The aerobic reactor of this invention can achieve mixed oxygen supply for wastewater treatment, with high oxygenation efficiency, high oxygen utilization rate, good treatment effect and sludge-water separation effect, and low oxygenation energy consumption.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, specifically relating to an aerobic reactor and a wastewater treatment method for wastewater treatment. Background Technology

[0002] Urban sewage mainly includes two types: domestic sewage and industrial sewage. Domestic sewage and many types of industrial sewage contain a large amount of organic pollutants, and some industrial sewage also contains toxic and harmful synthetic organic pollutants.

[0003] Aerobic activated sludge processes all require aeration devices to provide sufficient dissolved oxygen for microorganisms. Aeration devices are the core of biological treatment and a major source of energy consumption in urban wastewater treatment plants. The aeration system is a crucial component of urban domestic water treatment systems, playing a decisive role in wastewater treatment efficiency. The biological treatment unit is the most energy-intensive unit in a wastewater treatment plant, with the aeration system consuming approximately 40%-60% of the total energy for oxygen supply during biological treatment. Therefore, saving electricity is a vital way to achieve energy conservation and cost reduction in wastewater treatment plants, and reducing the electricity consumption of the aeration system for oxygen supply is the most effective and direct method.

[0004] CN 206553260 U discloses an aerobic reactor and wastewater treatment equipment. The aerobic reactor includes an aerobic reaction chamber and a gas-liquid separation chamber, and is equipped with an aeration disc, a gas external circulation pipe, and a turbulence-inducing mechanism. The wastewater treatment equipment includes the aforementioned aerobic reactor, and circulates gas from the gas-liquid separation chamber into the aerobic reaction chamber. Although this equipment can recycle gas, the aeration is insufficient, the oxygen mass transfer efficiency is low, and the effect on improving oxygen utilization is minimal.

[0005] CN 210367127 U discloses a novel aerobic reactor. This utility model relates to a novel aerobic reactor whose structure includes a tank, an aeration zone, a microbial reaction zone, a sludge-water separation zone, an inlet device, an outlet pipe, an air inlet device, and a sludge circulation device, all housed within the tank. The tank also includes a degassing chamber, and the degassing chamber, sludge-water separation zone, microbial reaction zone, and aeration zone are arranged from top to bottom. Although this reactor achieves wastewater recycling and effective sludge-water separation, its reliance on aeration results in low oxygen transfer efficiency, high aeration energy consumption, and limited energy-saving effect.

[0006] Therefore, it is essential to develop a more efficient and energy-saving wastewater treatment equipment, which is of great significance to the field of ecological environmental protection and the promotion of wastewater resource utilization. Summary of the Invention

[0007] In view of the above problems, the present invention provides an aerobic reactor for wastewater treatment, and a method for wastewater treatment using the aerobic reactor, so as to achieve more efficient and energy-saving wastewater treatment.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] An aerobic reactor for wastewater treatment includes a tank, a sludge-water separation device disposed at the upper part of the tank, and at least one set of hydraulic mixing and oxygen supply devices spaced apart along the height of the tank below the sludge-water separation device. The upper part of the side wall of the tank has a clear liquid outlet, the lower part has a wastewater inlet, and the top of the tank has at least one exhaust port.

[0010] A hydraulic mixing oxygen supply device includes a liquid distributor and a plurality of upper spray hydraulic agitators and lower spray hydraulic agitators evenly distributed on the left and right sides of the tank along the liquid distributor, wherein the number of upper spray hydraulic agitators is not less than the number of lower spray hydraulic agitators, and the liquid inlet and outlet of the liquid distributor are respectively connected to the sewage inlet and the liquid inlet of the hydraulic agitator.

[0011] A mud-water separation device includes a mud-water separation module and a horizontal annular baffle sandwiched between the upper outer part of the mud-water separation module and the inner side wall of the tank. The horizontal annular baffle is located below the clear liquid outlet. The area above the horizontal annular baffle is the clear liquid zone, and the area below it is the mud-water mixing zone.

[0012] In this invention, the tank contains activated sludge for the biodegradation of wastewater.

[0013] The present invention is further configured such that each of the hydraulic agitators includes an injection section, a mixing section, a contraction section and a diffusion section arranged sequentially from bottom to top. The bottom of the injection section is provided with a liquid inlet, the top of the diffusion section is provided with a liquid outlet, and at least one self-suction port is provided on the side wall of the mixing section. After the sewage entering through the injection section and the fluid sucked in through the self-suction port are mixed in the mixing section, they are sprayed out through the diffusion section.

[0014] It should be noted that the upward-spraying hydraulic agitator and the downward-spraying hydraulic agitator have the same structure, differing only in their placement when connected to the liquid distributor. In the upward-spraying hydraulic agitator, the nozzle of the diffuser section faces vertically upwards, and the inlet at the bottom of the injection section is connected to the outlet of the liquid distributor. Conversely, in the downward-spraying hydraulic agitator, the nozzle of the diffuser section faces vertically downwards, and the inlet of the injection section is connected to the outlet of the liquid distributor. In this invention, under the action of the opposing upward-spraying and downward-spraying hydraulic agitators, the mud-water mixture is sprayed upwards and downwards from both sides of the tank body, forming a vertical circulation inside the tank body below the mud-water separation device. The self-suction port on the hydraulic agitator is used to entrain the fluid inside the tank. Under the action of pressure difference, sewage outside the hydraulic agitator is sucked into the hydraulic agitator through the self-suction port and strongly mixed with sewage entering through the injection section in the mixing section, then sprayed out as a uniform fluid from the top outlet of the hydraulic agitator.

[0015] The present invention is further configured such that the lengths of the incident section L1, the mixing section L2, the contraction section L3, and the diffusion section L4, and the total length L of the hydraulic agitator have the following relationships: L1 / L = 0.35~0.43, L2 / L = 0.17~0.25, L3 / L = 0.04~0.08, L4 / L = 0.2~0.32; and the width d of the contraction section is greater than the length L3 of the contraction section.

[0016] The present invention is further configured such that the inner end of the incident section is a tapered section extending into the mixing section, the tapered section being frustum-shaped, and the angle β between its outer side wall and the vertical direction being 10°~32°; preferably, the angle β being 15°~25°.

[0017] The present invention is further configured such that the diameter of the injection nozzle of the tapered section is 10~15mm.

[0018] The present invention is further configured such that the mud-water separation module includes a plurality of separation partitions arranged in parallel at intervals along the horizontal direction, each separation partition including a vertical part and a bent part extending downward at an incline below the vertical part, and the upper middle two sides of the vertical part of each separation partition are connected to the horizontal annular baffle.

[0019] The present invention is further configured such that the included angle between the bent portion and the vertical portion is 15~35°.

[0020] The present invention is further configured such that the top of the vertical portion of the two outermost separation partitions in the mud-water separation module extends outward and upward at a second bend, which serves as an overflow weir for the clear liquid outlet.

[0021] The present invention is further configured such that the distance between two adjacent separation baffles is 15-30 mm. When the distance between two adjacent separation baffles is less than 15 mm, the activated sludge flocs are prone to clogging the channels, making it difficult for liquid to pass through, and the separation effect decreases; when the distance between adjacent separation baffles is greater than 30 mm, the activated sludge and the treated wastewater rise together, making it difficult to separate effectively, and the separation effect decreases.

[0022] The present invention is further configured such that a sludge collection tank is provided below the sludge-water separation device for collecting the sludge separated by the sludge-water separation module; a sludge circulation outlet is provided on the side wall of the tank between the bottom of the sludge collection tank and the top of the hydraulic mixing oxygen supply device; a sludge circulation inlet is provided on the side wall of the bottom of the tank below the hydraulic mixing oxygen supply device; a first sludge discharge port is provided at the bottom of the sludge collection tank; and the first sludge discharge port, the sludge circulation outlet, and the sludge circulation inlet are connected in sequence by pipes.

[0023] The present invention is further configured such that the sludge circulation inlet is also connected to a sludge inlet pipe for replacing new sludge.

[0024] The present invention is further configured such that a second sludge discharge port is provided at the bottom of the tank, the second sludge discharge port is connected to the sludge pool on the outside, and the sludge deposited at the bottom of the tank is discharged through the second sludge discharge port and then transported to the sludge pool by a sludge pump.

[0025] The invention is further configured such that the clear liquid outlet is connected to an outer water collection tank via a drain pipe, and a clear liquid return pipe is connected to the drain pipe, the other end of which is connected to the sewage inlet of the tank. This configuration allows a portion of the clear liquid discharged through the clear liquid outlet to return to the sewage inlet pipe.

[0026] The invention is further configured such that an exhaust valve is installed at the top of the tank to regulate the pressure inside the tank and ensure that the internal pressure of the reactor is maintained within a certain range. When the internal pressure is lower or higher than this range, the exhaust valve automatically adjusts its opening to regulate the pressure, thereby increasing the dissolved oxygen limit in the water and preventing damage to the reactor tank due to overpressure or vacuum.

[0027] The present invention is further configured such that a spare gas supply device is provided at the bottom of the tank below the hydraulic mixing oxygen supply device, the gas supply device being connected to an external oxygen source for supplementing oxygen supply.

[0028] The present invention is further configured such that the air intake device includes a plurality of bubble generators evenly distributed at the bottom of the tank; preferably, the bubble generators are micro-nano bubble generators.

[0029] In this invention, valves are installed on each connecting pipe in the aerobic reactor.

[0030] The present invention also provides a wastewater treatment method using the above-mentioned aerobic reactor, comprising the following steps:

[0031] (1) The mixture of wastewater to be treated and oxygen-enriched water enters the tank through the hydraulic mixing and oxygen supply device and is subjected to biological treatment by activated sludge. The liquid sprayed by the upper spray hydraulic agitator and the lower spray hydraulic agitator arranged opposite to each other forms a circulation in the tank.

[0032] (2) As the liquid level in the tank gradually rises, the mud-water mixture enters the mud-water separation module for mud-water separation. The separated clear liquid is discharged through the clear liquid outlet, and the separated sludge is deposited on the sludge collection tank and can be recycled.

[0033] (3) Part of the clear liquid discharged through the clear liquid outlet is collected, and part of it is returned to the tank through the liquid distributor.

[0034] The invention is further configured such that, after a certain amount of sludge has accumulated on the sludge collection tank, the sludge is discharged from the sludge collection tank and sequentially enters the tank through the sludge circulation outlet and sludge circulation inlet for recycling. After the wastewater treatment process is completed, the non-biologically active dead sludge deposited at the bottom of the tank is discharged through the second sludge discharge port.

[0035] Compared with the prior art, the present invention has the following beneficial technical effects:

[0036] (1) The present invention provides oxygen supply by adding a hydraulic mixing oxygen supply device in the sewage treatment tank, so that the oxygen-rich sewage mixture is mixed with the activated sludge, thereby strengthening the contact between the activated sludge and oxygen, improving the oxygen mass transfer efficiency, and thus providing sufficient oxygen for the survival of microorganisms and the decomposition of organic matter.

[0037] (2) The present invention uses a hydraulic stirrer as a mixing and oxygen supply device. Since it can self-suction the mixed liquid in the sewage treatment area through the self-suction inlet and then spray it out, the mixed liquid in the pool circulates. The upper and lower arrangement makes the liquid circulation in the microbial reaction zone generate liquid circulation. The hydraulic stirring of the sewage treatment pool is strengthened, avoiding the deposition of microorganisms at the bottom of the pool, increasing the contact area between microorganisms and oxygen and reactants, and promoting efficient sewage treatment.

[0038] (3) The present invention designs an integrated aerobic reactor structure for wastewater treatment, which integrates the reaction zone, mud-water separation zone and degassing zone. It has the advantages of small footprint and easy installation and operation. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the structure of the aerobic reactor used for wastewater treatment in this invention.

[0040] Figure 2 This is a front view of the hydraulic stirrer in this invention.

[0041] Figure 3 This is a side view of the hydraulic stirrer in this invention.

[0042] Figure 4 This is a vertical cross-sectional view of the hydraulic stirrer in this invention.

[0043] Figure 5 This is a top view of the mud-water separation module.

[0044] Figure 6 A top view of the liquid mixing oxygen supply device.

[0045] The components include: 1. Tank body; 1-1. Clear liquid outlet; 1-2. Sewage inlet; 1-3. Exhaust port; 1-4. Sludge circulation outlet; 1-5. Sludge circulation inlet; 1-6. Second sludge discharge port; 1-7. Exhaust valve; 2. Hydraulic mixing and oxygen supply device; 2-1. Liquid distributor; 2-2. Upper spray hydraulic agitator; 2-3. Lower spray hydraulic agitator; 2-1-1. Injection section; 2-1-2. Mixing section; 2-1-3. Contraction section; 2-1-4. Diffusion section; 2-1-5. Self-priming port; 2-1-6. Gradual contraction section; 3. Sludge-water separation device; 3-1. Sludge-water separation module; 3-1-1. Vertical section; 3-1-2. Bending section; 3-1-3. Second bending section; 3-2. Horizontal annular baffle; 4. Sludge collection tank; 5. Clear liquid return pipe; 6. Air supply device. Detailed Implementation

[0046] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. It should be understood that the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of the present invention.

[0047] Unless otherwise specified, the experimental methods described in the following examples are generally performed under standard conditions or as recommended by the manufacturer.

[0048] Example 1

[0049] refer to Figure 1 The present invention provides an aerobic reactor for wastewater treatment, comprising a tank 1, a mud-water separation device 3 disposed on the upper part of the tank 1, and at least one set of hydraulic mixing oxygen supply devices 2 disposed below the mud-water separation device 3 and spaced apart in the vertical direction. The upper part of the side wall of the tank 1 is provided with a clear liquid outlet 1-1, the lower part is provided with a wastewater inlet 1-2, and the top of the tank 1 is provided with at least one exhaust port 1-3.

[0050] The hydraulic mixing oxygen supply device 2 includes a liquid distributor 2-1, and a plurality of upward spray hydraulic agitators 2-2 and downward spray hydraulic agitators 2-3 evenly distributed along the liquid distributor 2-1 on the left and right sides of the tank body 1, respectively. The number of upward spray hydraulic agitators 2-2 is not less than the number of downward spray hydraulic agitators 2-3. The inlet and outlet of the liquid distributor 2-1 are respectively connected to the sewage inlet 1-2 and the inlet of the hydraulic agitators.

[0051] The mud-water separation device 3 includes a mud-water separation module 3-1 and a horizontal annular baffle 3-2 sandwiched between the upper outer part of the mud-water separation module 3-1 and the inner side wall of the tank 1. The horizontal annular baffle 3-2 is located below the clear liquid outlet 1-1.

[0052] In this embodiment, the water source entering the tank 1 is a mixture of sewage and oxygen-enriched water, and the tank 1 contains activated sludge.

[0053] In this embodiment, an exhaust valve 1-7 is also provided at the top of the tank body to regulate the pressure inside the tank body 1.

[0054] like Figure 2-4 As shown, each of the hydraulic agitators includes, from bottom to top, an injection section 2-1-1, a mixing section 2-1-2, a contraction section 2-1-3, and a diffusion section 2-1-4. The bottom of the injection section 2-1-1 is provided with a liquid inlet, and the top of the diffusion section 2-1-4 is provided with a liquid outlet. At least one self-suction port 2-1-5 is provided on the side wall of the mixing section 2-1-2. The sewage entering through the injection section 2-1-1 and the fluid sucked in through the self-suction port 2-1-5 are mixed in the mixing section 2-1-2 and then discharged through the diffusion section 2-1-4.

[0055] The following relationships exist between the length L1 of the incident section 2-1-1, the length L2 of the mixing section 2-1-2, the length L3 of the contraction section 2-1-3, the length L4 of the diffusion section 2-1-4, and the total length L of the hydraulic agitator: L1 / L = 0.35~0.43, L2 / L = 0.17~0.25, L3 / L = 0.04~0.08, L4 / L = 0.2~0.32; the width of the contraction section 2-1-3 is greater than the length L3 of the contraction section 2-1-3; the inner end of the incident section 2-1-1 is a tapered section 2-1-6 extending into the mixing section, the tapered section 2-1-6 is frustum-shaped, and the angle β between its outer wall and the vertical direction is 10°~32°.

[0056] Furthermore, the nozzle diameter of the tapered section 2-1-6 is 10~15mm.

[0057] like Figure 1 and 5As shown, the sludge-water separation module 3-1 includes several separation baffles arranged parallel to each other at intervals along a horizontal direction. Each separation baffle includes a vertical portion 3-1-1 and a bent portion 3-1-2 extending downwards at an incline below the vertical portion 3-1-1. The upper middle two sides of the vertical portion 3-1-1 of each separation baffle are connected to the horizontal annular baffle 3-2. The distance between two adjacent separation baffles is 15~30mm. The two outermost separation baffles in the sludge-water separation module 3-1 have a second bent portion 3-1-3 extending upwards and outwards from the vertical portion 3-1-1, which serves as an overflow weir for the clear liquid outlet. After the activated sludge settles, the clear liquid overflows into the overflow weir and is discharged through the clear liquid outlet 1-1.

[0058] Below the sludge-water separation device 3 is a sludge collection tank 4 for collecting the sludge separated by the sludge-water separation module 3-1. A sludge circulation outlet 1-4 is provided on the side wall of the tank body between the bottom of the sludge collection tank 4 and the top of the hydraulic mixing oxygen supply device 2. A sludge circulation inlet 1-5 is provided on the side wall of the bottom of the tank body 1 below the hydraulic mixing oxygen supply device 2. A first sludge discharge port is provided at the bottom of the sludge collection tank 4. The first sludge discharge port, the sludge circulation outlet 1-4, and the sludge circulation inlet 1-5 are connected sequentially by pipes. The sludge circulation inlet 1-5 is also connected to a sludge inlet pipe for replenishing new sludge. In this embodiment, the sludge collection tank 4 is shaped like a flat-bottomed funnel, which facilitates the collection of concentrated activated sludge.

[0059] The bottom of the tank 1 is provided with a second sludge discharge port 1-6, which is connected to the outer sludge pool. The sludge deposited at the bottom of the tank is transported to the sludge pool by a sludge discharge pump to discharge the dead sludge accumulated at the bottom of the tank.

[0060] The clear liquid outlet 1-1 is connected to the outer collection tank via a drain pipe. A clear liquid return pipe 5 is connected to the drain pipe, and the other end of the clear liquid return pipe 5 is connected to the sewage inlet 1-2 of the tank. This achieves the circulation treatment of sewage in the aerobic reactor, reduces the pollutant concentration of the inlet sewage, increases the reactor inlet flow rate, provides more powerful hydraulic stirring, and enhances the sewage treatment effect.

[0061] In this embodiment, a backup gas supply device 6 is also provided at the bottom of the tank 1 below the hydraulic mixing oxygen supply device 2. The gas supply device 6 is connected to an external oxygen source for supplementing oxygen supply. Preferably, the gas supply device 6 is a micro-nano bubble generator, which supplements oxygen supply through micro-nano bubbles. It should be noted that under normal conditions, the gas supply device is not turned on.

[0062] When using the aforementioned aerobic reactor for wastewater treatment, the wastewater to be treated and the oxygen-enriched water mixture are transported into the tank 1, where they undergo a biological reaction with aerobic microorganisms. Dissolved organic matter in the wastewater is decomposed by the microorganisms. The hydraulic mixing oxygen supply device 2 provides the necessary oxygen to the microorganisms and agitates the wastewater-activated sludge mixture through jet self-aspiration, keeping the microorganisms in suspension. Due to the different orientations of the hydraulic agitators in the hydraulic mixing oxygen supply device 2, circulation is generated within the microbial reaction area, resulting in more uniform dissolved oxygen in the water and enhancing the aerobic microbial reaction. As the liquid level in the tank gradually rises, the wastewater flows into the sludge-water separation device 3. After passing through the separation baffle, the activated sludge settles into the sludge collection tank 4, and the clear liquid enters the overflow weir and flows out of the reactor from the clear liquid outlet 1-1. A portion of the clear liquid returns to the hydraulic mixing and oxygen supply device 2 through the clear liquid return pipe 5 to increase the hydraulic stirring intensity. The activated sludge concentrated in the sludge collection tank 4 returns to the bottom of the tank 1 through the sludge circulation outlet 1-4 and the sludge circulation inlet 1-5 to achieve recycling. The waste gas generated by microbial respiration and reaction rises to the top of the tank 1 and is discharged through the exhaust port 1-3.

[0063] Example 2

[0064] A certain biochemical wastewater treatment pond uses the aerobic reactor and wastewater treatment process described in Example 1 to treat wastewater. Aerobic activated sludge is used as the microorganism for treating wastewater. After several days of stable operation, the COD concentration in the wastewater at the inlet and outlet of the wastewater treatment pond is recorded. The results are recorded in Table 1.

[0065] In this embodiment, as Figure 6 As shown, the hydraulic mixing oxygen supply device 2 has two sets, one above the other. The hydraulic distributors of the two sets are placed horizontally and vertically so that the hydraulic agitators are evenly distributed on both sides of the tank. The diameter of the tank is 1.8m, and the distance between the two sets of hydraulic agitators is 0.5m. Each set includes 5 hydraulic agitators, namely 3 upward spray hydraulic agitators and 2 downward spray hydraulic agitators. The hydraulic mixing of the liquid is achieved through the self-priming action of the jet, forming a circulation in the microbial reaction zone below the sludge collection tank, making the dissolved oxygen water more evenly distributed and enhancing the aerobic microbial reaction. The number of upward-spraying hydraulic mixing oxygen supply devices is greater than that of downward-spraying ones in order to overcome the influence of gravity. In the downward spraying area, the jet force combined with gravity makes it easier for the activated sludge to move downward; in the upward spraying area, the jet force provides the power for the activated sludge to move upward, but it needs to overcome gravity. Therefore, this area requires a greater jet force, i.e., more hydraulic mixing oxygen supply devices.

[0066] The hydraulic agitator has a self-priming inlet on its side wall. The length L of the hydraulic agitator is 120mm, and the diameter of the spray nozzle of the tapered section 2-1-6 is 10mm. The angle β between its outer side wall and the vertical direction is 20°. It has high liquid-liquid mixing efficiency, good mixing effect, and good jet stirring effect.

[0067] In this embodiment, the lower part of the tank 1 contains activated sludge with a concentration controlled at 3000 mg / L, and the dissolved oxygen concentration in the microbial reaction zone 2 is controlled at 0.4 mg / L. In this embodiment, the backup aeration device is not activated.

[0068] Comparative Example

[0069] Compared to Example 2, the difference lies in the absence of a hydraulic stirring device. Instead, a traditional aeration biological water treatment method is used, employing an aeration disc as the aeration device. An air compressor is used to supply gas to the aeration disc, and aeration occurs directly within the tank. The wastewater and microorganisms are the same as in Example 2. Under the same inlet flow rate, the COD concentrations at the wastewater inlet and outlet were recorded after the device had been running stably for several days, and compared with the results of Example 2. The results are recorded in Table 1. It should be noted that the COD concentration detected at the wastewater outlet is the same as the COD concentration detected in the clear liquid discharged through the clear liquid outlet 1-1.

[0070] Table 1. Inlet and outlet COD concentrations and removal rates

[0071]

[0072] According to the results of Example 2 and the comparative example, the technical solution adopted in Example 2 saves 81.37% of the energy consumption in the aeration system compared with the traditional aerated biological water treatment method, that is, reduces the daily power consumption by 166 kWh.

[0073] As can be seen from the results in Table 1, under the same inlet COD concentration, the outlet COD concentration of wastewater in Example 2 is significantly lower than that of the comparative example, its absorption efficiency is significantly higher, and its daily power consumption is also significantly lower. In conclusion, applying the wastewater treatment device and method improved by this invention in actual production will significantly reduce wastewater treatment costs.

[0074] Although the technical solutions of the present invention have been described and enumerated in detail, it should be understood that any modifications to the above embodiments or the adoption of equivalent alternatives shall fall within the scope of protection claimed by the present invention.

Claims

1. An aerobic reactor for sewage treatment, characterized by, The tank body is provided with a sludge-water separation device at the upper part of the tank body, and at least one set of liquid mixing oxygen supply devices is arranged along the height direction of the tank body below the sludge-water separation device, the upper part of the side wall of the tank body is provided with a clear liquid outlet, and the lower part is provided with a sewage inlet, and at least one exhaust port is arranged at the top end of the tank body. The liquid mixing oxygen supply device comprises a liquid distributor and a plurality of upper and lower liquid force mixers which are uniformly distributed on the left and right sides of the tank body along the liquid distributor, and the number of the upper liquid force mixers is not less than that of the lower liquid force mixers, the liquid inlet end and the liquid outlet end of the liquid distributor are connected to the sewage inlet and the liquid inlet end of the liquid force mixer respectively, each liquid force mixer comprises an incident section, a mixing section, a contraction section and a diffusion section arranged in sequence from bottom to top, the bottom of the incident section is provided with a liquid inlet, the top of the diffusion section is provided with a liquid outlet, at least one self-suction port is arranged on the side wall of the mixing section, the sewage entering through the incident section and the fluid sucked through the self-suction port are mixed in the mixing section and then sprayed out through the diffusion section, the length L1 of the incident section, the length L2 of the mixing section, the length L3 of the contraction section and the length L4 of the diffusion section and the total length L of the liquid force mixer satisfy the following relationships: L1 / L=0.35~0.43, L2 / L=0.17~0.25, L3 / L=0.04~0.08, L4 / L=0.2~0.32, the width d of the contraction section is greater than the length L3 of the contraction section, the inner side end of the incident section is a tapered section extending into the mixing section, the tapered section is a circular truncated cone, and the angle β between the outer side wall and the vertical direction is 10°~32°. The sludge-water separation device comprises a sludge-water separation module and a horizontal circular ring baffle arranged between the upper part of the outer side of the sludge-water separation module and the inner side wall of the tank body, and the horizontal circular ring baffle is arranged below the clear liquid outlet, the sludge-water separation module comprises a plurality of separation partitions arranged in parallel along the horizontal direction, the separation partition comprises a vertical part and a bent part extending downward and downward below the vertical part, and the upper middle part of the vertical part of each separation partition is connected to the horizontal circular ring baffle.

2. The aerobic reactor for sewage treatment according to claim 1, characterized in that, The top end of the vertical part of the outermost two separation partitions in the sludge-water separation module extends outward and upward with a second bent part as the overflow weir of the clear liquid outlet.

3. The aerobic reactor for sewage treatment according to claim 1, characterized in that, The distance between the two adjacent separation partitions is 15-30mm.

4. The aerobic reactor for sewage treatment according to claim 1, characterized in that, The sludge-water separation device is provided with a sludge collecting tank below for collecting the settled sludge, the side wall of the tank body between the bottom of the sludge collecting tank and the top of the liquid mixing oxygen supply device is provided with a sludge circulation outlet, the side wall of the bottom of the tank body below the liquid mixing oxygen supply device is provided with a sludge circulation inlet, the bottom end of the sludge collecting tank is provided with a first sludge discharge port, and the first sludge discharge port, the sludge circulation outlet and the sludge circulation inlet are sequentially connected by pipelines.

5. The aerobic reactor for sewage treatment according to claim 1, characterized in that, The bottom end of the tank body is provided with a second sludge discharge port connected to an external sludge pool, and the sludge deposited at the bottom of the tank body is transported into the sludge pool by a sludge discharge pump.

6. The aerobic reactor for sewage treatment according to claim 1, characterized in that, The clear liquid outlet is connected to an external water collecting tank through a drain pipe, a clear liquid return pipe is connected to the drain pipe, and the other end of the clear liquid return pipe is connected to the sewage inlet of the tank body.

7. A sewage treatment method using the aerobic reactor for sewage treatment according to any one of claims 1 to 6, characterized by, The method comprises the following steps: (1) the sewage to be treated and the mixed solution of oxygen-rich water enter the tank body through the liquid mixing and oxygen supply device, and are subjected to activated sludge biological treatment, wherein the liquid sprayed by the oppositely arranged upper and lower liquid jet mixers forms a circulating flow in the tank body; (2) as the liquid level in the tank body gradually rises, the sludge-water mixture enters a sludge-water separation module for sludge-water separation, the separated clear liquid is discharged through the clear liquid outlet, and the separated sludge is deposited on the sludge collecting tank and can be recycled; (3) part of the clear liquid discharged through the clear liquid outlet is collected, and part of the clear liquid is returned to the tank body through the liquid distributor.

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