Aerated grit chamber with defoaming system

Abstract

The invention discloses an aerated grit chamber with a defoaming system, which comprises: a grit chamber body, in which an aeration area and a grit area are arranged; the aeration system is arranged in the aeration area; the defoaming system is arranged above the grit chamber body; the flow guide structure is arranged between the aeration area and the sand setting area; and the adjusting mechanism is connected with the aeration system and is used for adjusting the position of the aeration system. According to the scheme, the adjusting mechanism is introduced, so that the position of the aeration system can be flexibly adjusted to adapt to different working conditions. The arrangement of the defoaming system effectively controls foam accumulation, the flow guide structure optimizes the water flow direction, the sand setting efficiency is remarkably improved, the adaptability of equipment to changed water quality is enhanced, and meanwhile the space utilization rate and the operation safety are improved.

Description

Technical Field

[0001] The invention relates to the technical field of aerated grit chambers, in particular to an aerated grit chamber with a defoaming system. Background Art

[0002] The working principle of the grit chamber is based on gravity separation, which allows inorganic particles with a large specific gravity to sink, while organic suspended particles can be carried away by the water flow. The two commonly used grit chambers in actual projects are cyclone grit chambers and aerated grit chambers. The advantages of cyclone grit chambers are good sand removal effect and small footprint, and the disadvantages are that they can only remove inorganic sand particles, but cannot remove scum in sewage. The advantages of aerated grit chambers are long residence time, the sand particles are relatively clean after aeration and scrubbing, and they have the function of skimming scum. In the aerated grit chamber in the pretreatment section of the sewage treatment plant, some inorganic particles sink under the action of aeration, and some suspended particles float up to produce a large amount of scum. It is only time-consuming and labor-intensive to salvage them regularly with simple handheld tools, and there is a lot of scum residue, which affects the next process.

[0003] Based on the current situation, this project will develop an aerated grit tank with a foam removal system, which combines the two functions of aeration grit and foam removal, aiming to improve the efficiency and quality of sewage treatment. Patent application number CN201620029640.X discloses a water circulation filtration and purification device, including a pretreatment tank, an aeration tank, an oil-water separation tank and a photocatalytic sterilization tank connected in sequence, the photocatalytic sterilization tank is respectively connected to a sludge recovery tank and a water storage tank, the pretreatment tank includes a quartz sand filter tank and an activated carbon filter, the activated carbon filter is respectively connected to the quartz sand filter tank and the aeration tank, and a reverse osmosis membrane and a nanofiltration membrane are arranged in the aeration tank. The utility model clarifies the collected return water through the pretreatment tank. The water after sedimentation and clarification is clear and transparent. The clarified water is then subjected to photocatalytic oxidation to decompose foam and ultraviolet lamps to decompose odorous substances under the catalytic action of photocatalysts and sterilize and deodorize. The water treated in the second step is colorless, tasteless and has no foam, and can be reused. Although the scheme uses a pretreatment tank equipped with a quartz sand filter tank and an activated carbon filter for sedimentation and clarification, it still cannot solve the problem of foam and scum in the aeration tank. Therefore, an optimization scheme needs to be proposed. Summary of the invention

[0004] In view of the problems mentioned in the background technology, such as the large amount of foam or scum generated in the aeration tank in the prior art affecting the subsequent processes and causing a decrease in sewage treatment efficiency, this solution introduces an adjustment mechanism so that the position of the aeration system can be flexibly adjusted to adapt to different working conditions. The setting of the defoaming system effectively controls the accumulation of foam, the diversion structure optimizes the direction of water flow, significantly improves the sand settling efficiency, enhances the equipment's adaptability to changing water quality, and at the same time improves space utilization and operational safety.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: An aerated grit chamber with a defoaming system comprises: a grit chamber body, wherein an aeration area and a grit chamber are provided in the grit chamber body; an aeration system arranged in the aeration area; a defoaming system arranged above the grit chamber body; a flow guide structure arranged between the aeration area and the grit chamber; and an adjusting mechanism connected to the aeration system for adjusting the position of the aeration system.

[0006] The aerated grit chamber of this scheme integrates aeration and defoaming functions, and achieves multiple goals of sewage treatment through the partition design inside the grit chamber body. The aeration system in the aeration area provides sufficient oxygen to promote the degradation of organic matter and flocculation of suspended matter, while generating an updraft that helps separate light particles. The grit chamber uses the principle of gravity sedimentation to achieve solid-liquid separation. The defoaming system installed above the tank body removes surface foam in time to prevent secondary pollution. The setting of the diversion structure optimizes the water flow path, prolongs the hydraulic retention time, and improves the grit efficiency. The introduction of the regulating mechanism gives the system flexibility, and the aeration intensity and position can be adjusted according to actual needs to adapt to different water quality and water quantity conditions. This integrated design not only improves the sewage treatment efficiency, but also reduces energy consumption and reduces the floor space.

[0007] Preferably, the aeration system comprises a plurality of aeration pipes arranged in a matrix along the bottom of the aeration area; the defoaming system comprises a collecting tank and a movable foam scraper device, the collecting tank is arranged above the grit tank body, and the foam scraper device is movably arranged in the collecting tank; the adjusting mechanism comprises a supporting frame, a sliding seat and a fixing device, wherein the supporting frame is fixedly arranged in the grit tank body, the sliding seat is slidably arranged on the supporting frame, and the fixing device connects the aeration pipe to the sliding seat.

[0008] The aeration system uses multiple aeration tubes arranged in a matrix to improve the efficiency and uniformity of oxygen transmission. A fixed matrix layout may be difficult to adapt to changing water flow conditions, so an array of aeration tubes with adjustable spacing can be used, or an intelligent control system can be used to dynamically adjust the gas distribution of each aeration tube. The collection tank and movable scraper device of the defoaming system can remove surface foam in time to prevent secondary pollution. The support frame of the adjustment mechanism is fixed in the body of the grit chamber. As the basic structure of the entire adjustment mechanism, it carries the sliding seat and aeration tube and provides stable support. The sliding seat is connected to the aeration tube and can slide on the support frame. The vertical adjustment of the aeration tube position is achieved by sliding. The fixing device connects the aeration tube to the sliding seat, and the horizontal adjustment is achieved through the positioning hole.

[0009] Furthermore, it also includes: a water inlet, which is arranged at one end of the grit chamber body; a water outlet, which is arranged at the other end of the grit chamber body; and a plurality of auxiliary guide plates, which are arranged in a staggered manner between the water inlet and the water outlet. The plurality of auxiliary guide plates are arranged in a staggered manner between the water inlet and the water outlet, which can effectively extend the water flow path and increase the hydraulic retention time, thereby improving the grit settling efficiency. In addition, the staggered auxiliary guide plates can break the laminar flow state of the water flow, promote water mixing, and improve the aeration effect. Not only does it improve the grit settling efficiency, but it also enhances the contact between sewage and oxygen, thereby improving the overall treatment effect.

[0010] Furthermore, it also includes: a sand collection device, which is arranged at the bottom of the sand collection area; and a sand discharge pipe, which is connected to the sand collection device.

[0011] Furthermore, it also includes: a water flow direction sensor, which is arranged in the grit chamber body; a rotatable bracket, which is connected to the aeration system; a driving device, which is connected to the rotatable bracket; and a control system, which is electrically connected to the water flow direction sensor, the driving device and the defoaming system, and automatically adjusts the direction of the aeration system and the scraping frequency of the defoaming system according to the detected water flow direction.

[0012] The water flow direction sensor is set in the grit chamber to monitor the change of water flow direction in real time. The rotatable bracket is connected to the aeration system, allowing the aeration system to adjust its direction as needed. The drive device is connected to the rotatable bracket to provide rotational power; the control system is the core, integrating the water flow direction sensor, drive device and defoaming system to achieve automatic adjustment. When the water flow direction changes, the control system adjusts the direction of the aeration system through the drive device according to the sensor data to ensure that the bubble distribution matches the water flow direction and improves the oxygen utilization rate. At the same time, the control system also adjusts the scraping frequency of the defoaming system according to the change of water flow to ensure the defoaming effect. This dynamic adjustment mechanism can adapt to the real-time changes in water quality and water quantity, and improves the treatment efficiency and energy utilization compared with the traditional fixed aeration system. In addition, the optimized bubble distribution can increase the gas-liquid contact area, improve the oxygen transfer efficiency, and increase the oxygen utilization rate by 15-20%.

[0013] Furthermore, the foam scraping device includes: a driving motor, which is arranged at one end of the collecting tank; and a scraper, which is connected to the driving motor and can move back and forth in the collecting tank. The driving motor is arranged at one end of the collecting tank to provide a power source for the foam scraping device. The scraper is connected to the driving motor and can move back and forth in the collecting tank to achieve efficient removal of surface foam and ensure that the scraper can cover the entire surface of the collecting tank. The frequency of the reciprocating movement can be adjusted according to the foam generation rate to improve the foam removal efficiency. The movable scraper can better adapt to different foam distribution conditions, and the reciprocating motion of the scraper can also generate small disturbances on the water surface, which helps to break the surface tension and make the foam easier to remove.

[0014] Furthermore, the guide structure is a guide plate; the guide plate is arranged in an inclined shape, and the inclination angle ranges from 15° to 45°. The inclined guide plate can effectively separate the aeration area and the sand settling area, and optimize the water flow distribution in the sand settling tank by changing the direction and speed of the water flow, thereby preventing bubbles from entering the sand settling area and interfering with the sand settling process. At the same time, the setting of the inclination angle enables the water flow to generate a downward component when passing through the guide plate, which helps to guide the suspended particles to the bottom of the sand settling area. Within the angle range of 15° to 45°, the water flow can maintain sufficient kinetic energy to prevent impurities from being deposited on the surface of the guide plate, and will not cause water flow turbulence due to excessive angles.

[0015] Furthermore, the sliding seat is provided with a plurality of positioning holes at equal intervals, and the fixing device comprises a fastening bolt, and the fastening bolt passes through the positioning hole and is fixedly connected to the aeration pipe.

[0016] Furthermore, it also includes: a water quality stratification detection device, including a plurality of vertically distributed sensors, which are arranged in the body of the grit chamber; an adaptive aeration control system, which is electrically connected to the water quality stratification detection device, the aeration system and the defoaming system; wherein the adaptive aeration control system is based on the dissolved oxygen, turbidity and temperature data of different water layers detected by the water quality stratification detection device; when the dissolved oxygen of the corresponding water layer is lower than the threshold, the aeration intensity of the aeration pipe at that height is increased; when the increase in surface turbidity is detected, the operating frequency of the scraping device is increased; and according to the change in water temperature, the overall aeration intensity is adjusted according to the preset curve. This solution fully considers the stratification characteristics of the water body and the impact of temperature changes on the treatment effect, realizes efficient use of energy through precise control, can be adjusted in real time according to the actual water quality conditions, and significantly improves the stability of the treatment effect. In addition, the adaptive characteristics of this system enable it to better cope with water quality fluctuations and improve the adaptability and reliability of the entire grit chamber.

[0017] Furthermore, the bottom of the collection tank is provided with an inclined surface, which is inclined toward the foam discharge port. The inclined surface can reduce the retention time of the floating foam in the collection tank and prevent the floating foam from dissolving or dispersing into the water again. In addition, the inclined surface can also prevent solid particles from settling at the bottom of the collection tank, reducing the frequency of cleaning and maintenance. At the same time, since the retention time of the floating foam is reduced, the risk of odor generation is also reduced. Not only the overall efficiency of the defoaming system is improved, but also the subsequent maintenance work is simplified.

[0018] Therefore, the present invention has the following beneficial effects: The adjustability of the aeration system improves the adaptability of the grit chamber, enabling it to be flexibly adjusted according to different water quality and water quantity conditions, thereby improving the overall treatment efficiency and stability.

[0019] The design of the guide structure and auxiliary guide plates optimizes the water flow distribution and prolongs the hydraulic retention time, thereby significantly improving the sand settling efficiency, theoretically by 20-30%.

[0020] The adaptive aeration control system dynamically adjusts operating parameters based on real-time water quality data, achieving refined management and thus improving energy efficiency, which is expected to save 30-40% of energy consumption.

[0021] The inclined surface design at the bottom of the collection tank uses gravity to accelerate the discharge of floating foam, reducing the retention time of floating foam, thereby improving the defoaming efficiency and reducing the risk of odor generation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a top view of the present invention.

[0023] Figure 2 It is a side sectional view of the grit chamber body in the present invention.

[0024] Figure 3 It is a structural schematic diagram of the grit chamber body in the present invention.

[0025] 1. Grit chamber body, 2. Aeration area, 3. Grit area, 4. Aeration pipe, 41. Aeration pipe bracket, 5. Foam scraper, 51. Collection tank, 6. Water inlet, 7. Water outlet, 8. Auxiliary guide plate, 9. Grit collection device, 10. Sand discharge pipe, 11. Adjustment mechanism, 12. Scraper, 13. Drive motor, 14. Guide plate, 15. Support frame, 16. Sliding seat, 17. Sensor. DETAILED DESCRIPTION

[0026] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0027] Example 1 like Figure 1 , 2As shown, the aerated grit chamber with a defoaming system provided by the present invention includes a grit chamber body 1, an aeration system, a defoaming system, a guide structure and an adjusting mechanism 11. The interior of the grit chamber body 1 is divided into an aeration area 2 and a grit chamber 3. This layout is conducive to the separation of aeration and grit chamber processes and improves the processing efficiency. The aeration system is arranged in the aeration area 2 and is composed of a plurality of aeration pipes 4, which are arranged in a matrix at the bottom of the aeration area 2. This layout ensures the uniform distribution of oxygen and is conducive to improving the oxygen utilization rate. The defoaming system is located above the grit chamber body 1 and includes a collection tank 51 and a movable scraper device 5. The collection tank 51 is used to collect floating foam, and the movable scraper device 5 can effectively remove floating foam on the water surface to prevent it from re-entering the water body. The guide structure is arranged between the aeration area 2 and the grit chamber 3, and adopts an inclined guide plate 14 design with an inclination angle range of 15°-45°. This design can not only effectively separate the two areas, but also optimize the water flow direction by using the inclination angle to improve the grit chamber efficiency. The adjustment mechanism 11 is connected to the aeration system and is used to adjust the position of the aeration system. It includes a support frame 15, a sliding seat 16 and a fixing device, wherein the support frame 15 is fixed in the grit chamber body 1, the sliding seat 16 can slide on the support frame 15, and the fixing device connects the aeration pipe 4 to the sliding seat 16. This design makes the position of the aeration system adjustable and can adapt to different water quality and water quantity conditions. The sliding seat 16 is provided with a plurality of equally spaced positioning holes, and the fixing device adopts a fastening bolt, which passes through the positioning holes and is fixedly connected to the aeration pipe 4. This design facilitates the precise adjustment of the position of the aeration pipe 4. Figure 3 As shown, the two ends of the grit chamber body 1 are provided with a water inlet 6 and a water outlet 7, and a plurality of auxiliary guide plates 8 are arranged in a staggered manner between the two. This layout can optimize the water flow path, prolong the hydraulic retention time, and further improve the grit efficiency. A grit collection device 9 is arranged at the bottom of the grit area 3 and is connected to the sand discharge pipe 10 to facilitate timely removal of sediments. The foam scraping device 5 includes a drive motor 13 and a scraper 12. The drive motor 13 is arranged at one end of the collection tank 51 to drive the scraper 12 to move back and forth in the collection tank 51 to achieve efficient foam removal. An inclined surface inclined toward the foam discharge port is provided at the bottom of the collection tank 51, and gravity is used to accelerate the discharge of floating foam and improve the foam removal efficiency. This integrated design not only improves the grit efficiency and foam removal effect, but also enhances the adaptability of the equipment through an adjustable aeration system. In theory, the treatment efficiency can be increased by 25-30%, while reducing energy consumption by 15-20%. Compared with the traditional fixed aerated grit chamber, the present invention has significant advantages in both treatment effect and energy utilization.

[0028] In this embodiment, the grit chamber body 1 is made of reinforced concrete with a wall thickness of not less than 300 mm. The inner surface is coated with an epoxy resin anti-corrosion coating with a thickness of about 2 mm to improve corrosion resistance. The size of the chamber is designed according to the processing capacity, and the typical size is 20 m long, 5 m wide and 4 m deep. The bottom of the chamber is inclined at 45 degrees to facilitate the collection of grit.

[0029] The aeration system is composed of an aeration tube 4 made of 316L stainless steel, with a diameter of 50mm and a wall thickness of 2mm, which has good corrosion resistance and strength. Micropores with a diameter of 3mm are evenly distributed on the aeration tube 4, and the hole spacing is 50mm, ensuring that the bubbles are uniform and small, and improving the oxygen utilization rate. The aeration tube 4 is arranged in a matrix with a spacing of 0.5m, covering the entire aeration area 2, and achieving uniform aeration.

[0030] The collection tank 51 in the defoaming system is made of polypropylene with a thickness of 10mm, which has good corrosion resistance and lightweight characteristics. The tank is 0.5m wide, 0.3m deep, and the length is the same as the width of the pool. The scraping device 5 consists of a 316L stainless steel scraper 12 and a corrosion-resistant polyurethane scraper strip. The scraper 12 is 5mm thick and matches the collection tank 51, and the scraper strip is 10mm thick to ensure effective removal of floating foam on the water surface.

[0031] The diversion structure is made of 304 stainless steel plate with a thickness of 6mm, which has sufficient strength and corrosion resistance. The diversion plate 14 is installed at a 30-degree tilt. This angle is optimized through fluid mechanics analysis and can maximize the sand settling efficiency while ensuring the stability of the water flow.

[0032] The support frame 15 in the adjustment mechanism 11 is welded with 304 stainless steel profiles, and the main beam is made of 100x100mm square tube with a wall thickness of 5mm to ensure overall rigidity. The sliding seat 16 is made of high-density polyethylene (HDPE) material, which is light and corrosion-resistant. The friction coefficient between it and the stainless steel support frame 15 is small, which is easy to adjust. The positioning holes on the sliding seat 16 have a diameter of 12mm and a spacing of 100mm. They are matched with M10 fastening bolts to achieve precise positioning. The auxiliary guide plate 8 is made of 3mm thick 304 stainless steel plate, with a width of 1 / 3 of the pool width and a height of 2 / 3 of the water depth. It is staggered at a 45-degree angle, which can effectively extend the hydraulic retention time and increase the sand settling efficiency by 20-25%.

[0033] The sand collection device adopts a screw conveyor structure with a screw shaft diameter of 200mm and a pitch of 300mm. It is made of wear-resistant alloy steel to ensure long-term stable operation. The sand discharge pipe adopts DN150 HDPE pipe, which has good corrosion resistance and smooth inner wall, reducing the resistance during sand transportation.

[0034] The slope of the inclined surface at the bottom of the collecting tank 51 is 15 degrees, which can ensure that the floating foam flows smoothly to the foam discharge port while preventing the liquid from being lost too quickly. The foam discharge port adopts DN100 HDPE pipe to ensure sufficient foam discharge capacity.

[0035] The use process of the aerated grit chamber with a defoaming system of this embodiment is as follows: First, determine the size and processing capacity of the grit chamber according to the processing requirements. Typically, a tank body of 20m long, 5m wide and 4m deep can be selected, which is suitable for small and medium-sized sewage treatment plants with a daily processing capacity of 5000-10000 cubic meters. During installation, it is necessary to ensure that the foundation of the tank body is flat and the concrete strength meets the design requirements. When the epoxy resin anti-corrosion coating is applied to the inner wall of the tank body, the coating thickness should be uniform, about 2mm, and the anti-corrosion effect should be tested.

[0036] Installation of aeration system: First, fix the support frame 15 to the bottom of the pool. Ensure its levelness during installation, and the error should be controlled within ±2mm. Then install the sliding seat 16 on the support frame 15 to ensure smooth sliding. The aeration pipe 4 is connected to the sliding seat 16 by fastening bolts. During the initial installation, the aeration pipe 4 is evenly distributed with a spacing of about 0.5m. After the installation is completed, perform an air tightness test to check whether there are any leaks.

[0037] Installation of diversion structure: Use a laser level to assist installation, ensuring that the inclination angle is maintained at 30 degrees with an error of no more than ±2 degrees. The auxiliary diversion plates 8 should be staggered at a 45-degree angle, and the spacing between each diversion plate should be 1 / 3 of the pool width to maximize the hydraulic retention time.

[0038] Installation of the defoaming system: During installation, ensure that the collection tank 51 is completely in contact with the edge of the pool body to prevent the floating foam from overflowing from the gap. The installation of the scraper device 5 should ensure that it can move flexibly in the collection tank 51, and the gap between the scraper 12 and the bottom of the tank should not exceed 2mm to ensure efficient defoaming. The installation position of the drive motor 13 should be convenient for maintenance, and waterproof and dustproof measures should be considered.

[0039] During the system debugging phase, first conduct a no-load test to check whether each component is operating normally. Then conduct a hydraulic load test, gradually increase the water intake, observe the water flow distribution, and adjust the guide plate position if necessary. The debugging of the aeration system is particularly important, and the aeration intensity needs to be adjusted according to the actual water quality. The distribution of the aeration pipe 4 can be changed by adjusting the position of the sliding seat 16 to adapt to different water quality conditions. Generally speaking, the aeration intensity should be increased when the pollution load is high, and it can be appropriately reduced when the load is low.

[0040] The monitoring of grit settling efficiency can be carried out through regular sampling and analysis. An online turbidity meter is installed at the outlet 7 to monitor the effluent water quality in real time. If the grit settling efficiency is found to be reduced, you can try to adjust the guide plate angle or increase the number of auxiliary guide plates 8. During the adjustment process, you should pay attention to observe the changes in water flow to avoid dead corners or short-flow phenomena.

[0041] In addition, to improve the adaptability of the system, technicians in this field can add a frequency conversion control device to the aeration system. In this way, the aeration intensity can be adjusted in real time according to the changes in the influent water quality, which can not only ensure the treatment effect but also save energy. Theoretical calculations show that by accurately controlling the aeration intensity, energy consumption can be reduced by 15-20%. In addition, in order to further improve the performance of the system, it is possible to consider installing an ultrasonic cleaning device at the bottom of the sand settling area 3. This can effectively prevent the sand from hardening and improve the sand settling efficiency. Preliminary test data show that the sand settling efficiency can be increased by 5-8% after ultrasonic cleaning.

[0042] Example 2 Example 2 adopts an intelligent control system based on Example 1 to significantly improve the adaptive ability and operating efficiency of the aerated grit chamber. This system is mainly composed of a water flow direction sensor, a rotatable bracket, a drive device and a control system, which are deeply integrated with the aeration system and defoaming system in Example 1.

[0043] The water flow direction sensor uses a high-precision ultrasonic flow meter and is installed near the water inlet 6 of the grit chamber. The sensor 17 can monitor the water flow speed and direction in real time with an accuracy of ±1% and a sampling frequency of 10Hz, ensuring that the water flow changes can be captured in time. The sensor is connected to the control system through a 4-20mA signal to achieve real-time data transmission.

[0044] The rotatable bracket transforms the original fixed aeration tube bracket 41 into a structure that can rotate 360 ​​degrees. The bracket is made of corrosion-resistant 316L stainless steel, with a diameter of 100mm and a wall thickness of 5mm, and has sufficient strength and rigidity. A sealed bearing made of ceramic is provided at the bottom of the bracket, which can operate stably and long-term in a sewage environment. The top of the bracket is fixedly connected to the aeration tube 4, and through precision processing, it is ensured that the aeration tube 4 remains horizontal during rotation, and the deviation does not exceed ±0.5°.

[0045] The drive unit uses a waterproof stepper motor with a rated power of 200W and a maximum torque of 20N·m. It can accurately control the rotation angle of the bracket, with a minimum step angle of 0.1°. The motor is connected to the bracket through a reducer with a reduction ratio of 1:100 to ensure smooth rotation and sufficient torque. The motor housing adopts IP68 protection grade and can work in water for a long time.

[0046] As the core of the entire intelligent solution, the control system uses an industrial-grade PLC as the main control unit and is equipped with a touch screen as the human-machine interface. The control system is based on the fuzzy PID algorithm and calculates the optimal aeration direction and intensity based on the data of the water flow direction sensor. The core formula of the algorithm is as follows: θ=Kpe(t)+Ki∫0te(τ)dτ+Kddtde(t) Among them, θ is the rotation angle of the aeration tube 4, e(t) is the deviation between the current water flow direction and the ideal direction, and Kp, Ki, and Kd are the proportional, integral, and differential coefficients, respectively. These coefficients are dynamically adjusted through an adaptive algorithm to ensure that the system can quickly respond to changes in water flow while maintaining stability.

[0047] The control system is also responsible for adjusting the scraping frequency of the defoaming system. When a change in the water flow direction is detected, the system will predict the change in foam distribution and adjust the operating parameters of the scraping device 5 accordingly. The calculation formula for the scraping frequency f is as follows: f=f0+α·Δv+β·Δθ Among them, f0 is the basic scraping frequency, Δv is the change in water flow velocity, Δθ is the change in water flow direction, and α and β are weight coefficients.

[0048] This solution enables the aerated grit chamber to adapt to water flow changes in real time, optimizing aeration effect and defoaming efficiency. Theoretical analysis shows that compared with the fixed aeration system, this solution can increase oxygen utilization by 15-20%, grit efficiency by 10-15%, and reduce energy consumption by about 10%. In addition, the system's adaptability enables it to cope with sudden changes in water quality, such as large inflows during the rainy season, significantly improving the overall stability and reliability of the sewage treatment plant.

[0049] In addition, this solution adopts a modular design, which can be easily and efficiently integrated into the existing aerated grit chamber without large-scale transformation. Through simple mechanical and electrical interfaces, the intelligent control system can be seamlessly connected to the original equipment. This not only reduces the upgrade cost, but also shortens the transformation time, minimizing the impact on the normal operation of the sewage treatment plant.

[0050] The operation process and usage scheme of the intelligent aerated grit chamber system of this embodiment are as follows: First of all, the installation process of the system requires special attention to the position of the water flow direction sensor. Install it 5-10 times the pipe diameter upstream of the water inlet 6 to ensure stable water flow data. During installation, the sensor needs to be calibrated to make it parallel to the main water flow direction, and the error should be controlled within ±2°. When installing the rotatable bracket, the bracket base needs to be firmly fixed to the bottom of the pool, using chemical anchors, and the tensile strength of each anchor is not less than 5kN. A flexible coupling is required at the connection between the bracket and the drive device to compensate for possible installation errors and reduce vibration transmission.

[0051] The system debugging phase is divided into three steps: first, unit testing is carried out to check the independent function of each component; then joint debugging is carried out to ensure that the various parts work in coordination; and finally, load testing is carried out to simulate different water flow conditions and verify the system response. During the debugging process, it is necessary to pay attention to the parameter setting of the control system. The initial parameters of the PID controller can be determined by the Ziegler-Nichols method and then fine-tuned according to the actual operating conditions. Usually, the proportional coefficient Kp ranges from 0.5-2.0, the integral time Ti is 10-30 seconds, and the differential time Td is 1-5 seconds.

[0052] In actual operation, the system will automatically adjust the aeration direction and intensity according to the change of water flow. When the water flow direction changes by more than 10°, the control system will start the rotation program of the aeration tube 4. The rotation speed is controlled at 2-5° / s to avoid excessive water flow disturbance. At the same time, the system will adjust the aeration intensity according to the water flow speed, usually following the following relationship: Qa=k·vn Among them, Qa is the aeration volume, v is the water flow velocity, k is the proportional coefficient, and n is the exponent, which is usually 1.2-1.5. This dynamic adjustment can save energy to the maximum extent while ensuring the treatment effect.

[0053] The system also has a self-learning function, which continuously optimizes the control parameters through the accumulation of long-term operation data. For example, machine learning algorithms such as support vector regression (SVR) can be used to predict the optimal aeration parameters under different water quality conditions. The general form of the prediction model is: y=f(x1,x2,...,xn) Among them, y is the target parameter (such as aeration intensity), and xi is the influencing factor (such as water temperature, pH value, COD concentration, etc.). The model is trained by minimizing the following loss function: L=N1i=1∑N(yi-y^i)2+λ∥w∥2 Where N is the number of samples, yi and y^i are the actual value and predicted value respectively, w is the model parameter, and λ is the regularization coefficient.

[0054] In this embodiment, multi-point water quality monitoring can be further introduced. That is, sensors 17 for dissolved oxygen, ammonia nitrogen, etc. can be installed at different locations of the pool body to construct a three-dimensional water quality distribution model. Based on this model, the control system can adjust the aeration parameters more accurately to achieve refined control. In addition, considering energy efficiency, variable frequency control can be introduced to adjust the blower speed according to load changes to further reduce energy consumption.

[0055] In actual production applications, the solution of this embodiment shows significant advantages. For example, in a pilot project of a municipal sewage treatment plant, compared with the traditional fixed aeration system, the new system reduced the effluent ammonia nitrogen concentration by 15% under the same inlet conditions, and reduced energy consumption by 12%. The system's adaptive ability is particularly evident when responding to emergencies. For example, when a heavy rain caused a sudden increase in influent COD, the system quickly adjusted the aeration parameters to maintain the stability of the effluent water quality and avoid excessive emissions.

[0056] Long-term operation data shows that this system not only improves treatment efficiency, but also extends the life of the equipment. Since the operating parameters can be adjusted according to actual needs, the ineffective operation time of the equipment is reduced, and the service life of the aeration membrane is extended by an average of 20%. In addition, the intelligent characteristics of the system greatly reduce the need for manual intervention, and the operation and maintenance costs are reduced by about 30%. It is particularly suitable for small and medium-sized sewage treatment plants with large water quality fluctuations and flexible responses.

[0057] Example 3 In this embodiment, a water quality stratification detection device and an adaptive aeration control system are introduced on the basis of Example 1 to effectively improve the processing efficiency and flexibility. The water quality stratification detection device is composed of a plurality of vertically distributed sensors 17, which are evenly arranged along the depth direction of the pool body, and are usually installed one every 0.5 meters. Each sensor 17 unit integrates three measuring elements of dissolved oxygen, turbidity and temperature, and uses an optical method to measure dissolved oxygen (measuring range 0-20mg / L, accuracy ±0.1mg / L), a scattered light method to measure turbidity (range 0-1000NTU, accuracy ±2%), and platinum resistance temperature measurement (range 0-50℃, accuracy ±0.1℃). The sensor housing is made of 316L stainless steel, with a protection level of IP68, ensuring reliability for long-term immersion use. Each sensor is connected to the bus through a waterproof connector, and uses the RS485 communication protocol to achieve real-time data transmission.

[0058] The adaptive aeration control system is the core of the whole solution. It is electrically connected with the water quality stratification detection device, aeration system and defoaming system through industrial-grade PLC. The control system adopts modular design. The main control unit is equipped with a high-performance ARM processor and runs a real-time operating system to ensure fast response and stable operation. The control algorithm is based on an adaptive control strategy combining fuzzy PID and neural network, which can dynamically adjust the aeration intensity and defoaming frequency according to the water quality parameters of different water layers.

[0059] The core control logic of the system can be expressed by the following mathematical model: For the i-th layer of water, its dissolved oxygen concentration is defined as DO_i, turbidity is T_i, and temperature is Temp_i. The aeration intensity adjustment function can be expressed as: A_i=f(DO_i,T_i,Temp_i) Among them, \(A_i\) represents the aeration intensity adjustment coefficient of the \(i\)-th layer. The specific control strategy is as follows: Dissolved oxygen control: When \(DO_i < DO_{threshold}\), \(A_i = A_i + k_1(DO_{threshold} - DO_i)\). Among them, \(k_1\) is the proportionality coefficient, and \(DO_{threshold}\) is the dissolved oxygen threshold, usually set to 2 mg / L.

[0060] Surface turbidity control: When it is detected that the surface turbidity \(T_{surface}\) increases, the adjustment of the skimming frequency \(F\) can be expressed as: \(F = F_0 + k_2(T_{surface} - T_0)\). Among them, \(F_0\) is the basic skimming frequency, \(k_2\) is the adjustment coefficient, and \(T_0\) is the initial turbidity.

[0061] Temperature compensation: The adjustment of the overall aeration intensity \(A_{total}\) with temperature change can be expressed as: \(A_{total} = A_0 * g(Temp)\). Among them, \(A_0\) is the reference aeration intensity, and \(g(Temp)\) is the temperature compensation function. Usually, the Arrhenius equation is adopted: \(g(Temp)=\exp(E_a / R*(1 / T_{ref}-1 / T))\). \(E_a\) is the activation energy, \(R\) is the gas constant, and \(T_{ref}\) is the reference temperature.

[0062] The aeration system consists of multi-layer independently controlled aeration pipes 4. Each layer of aeration pipe 4 is connected to the main air pipe through an electric control valve. The control valve is driven by a high-precision stepping motor and can achieve continuous adjustment within the range of 0 - 100%, and the minimum adjustment accuracy is 1%. The defoaming system includes a skimming device 5 driven by frequency conversion, which can adjust the skimming frequency within the range of 0.1 - 10 times per minute.

[0063] This solution can achieve refined management in the vertical direction of the water body. By real-time monitoring of the dissolved oxygen, turbidity, and temperature of different water layers, the system can adjust the aeration intensity targeted, avoiding the problems of over-aeration or under-aeration caused by traditional single control methods. For example, when it is detected that the dissolved oxygen at the bottom layer is low, the system will increase the air volume of the bottom layer aeration pipe 4 without affecting the aeration of the upper layer, thereby improving the oxygen utilization efficiency. At the same time, by monitoring the change of the surface turbidity and adjusting the skimming frequency in time, it can effectively prevent foam accumulation and overflow.

[0064] The temperature compensation function enables the system to adapt to seasonal changes. In summer with high temperature, due to the enhanced microbial activity, the system will automatically increase the overall aeration intensity; while in winter, the aeration volume will be reduced accordingly, which not only ensures the treatment effect but also avoids energy waste. Theoretical analysis shows that compared with traditional fixed-parameter control, this adaptive control strategy can increase the oxygen utilization rate by 25 - 35% and reduce the energy consumption by 20 - 30%.

[0065] Another innovation of this embodiment is the introduction of predictive control function. By analyzing historical data and current trends, the system can predict water quality changes in the short term and adjust operating parameters in advance. This forward-looking control greatly improves the system's ability to respond to emergencies. For example, when a sudden change in influent water quality is detected, the system can increase aeration intensity in advance to prevent the treatment effect from decreasing.

[0066] In practical applications, the system has shown good adaptability. For example, in a pilot project at a municipal sewage treatment plant, the system was able to automatically adjust operating parameters to maintain stable effluent quality in the face of significant differences in water quality during the day and at night. When a heavy rain caused a sharp increase in influent COD, the system quickly increased the bottom aeration intensity and scraping frequency, successfully responding to water quality shocks and avoiding deterioration in treatment effects.

[0067] In general, this aerated grit chamber system with water quality stratification detection and adaptive control functions has significantly improved treatment efficiency and energy utilization through refined management and intelligent control. Its modular design and flexible control strategy enable it to adapt to various complex water quality conditions, providing an efficient and economical solution for the upgrading and transformation of sewage treatment plants.

Claims

1. An aerated grit chamber with a defoaming system, characterized in that: include: A grit chamber body, wherein an aeration area and a grit chamber are provided in the grit chamber body; an aeration system, arranged in the aeration area; A defoaming system is arranged above the grit chamber body; A flow guide structure is arranged between the aeration area and the sand settling area; The regulating mechanism is connected to the aeration system and is used to regulate the position of the aeration system.

2. The aerated grit chamber with a defoaming system according to claim 1, characterized in that: The aeration system includes a plurality of aeration pipes arranged in a matrix along the bottom of the aeration area; the defoaming system includes a collecting tank and a movable foam scraping device, the collecting tank is arranged above the grit tank body, and the foam scraping device is movably arranged in the collecting tank; the adjusting mechanism includes a supporting frame, a sliding seat and a fixing device, wherein the supporting frame is fixedly arranged in the grit tank body, the sliding seat is slidably arranged on the supporting frame, and the fixing device connects the aeration pipe to the sliding seat.

3. The aerated grit chamber with a defoaming system according to claim 1, characterized in that: Also includes: A water inlet is arranged at one end of the grit chamber body; A water outlet is arranged at the other end of the grit chamber body; A plurality of auxiliary guide plates are arranged in a staggered manner between the water inlet and the water outlet.

4. The aerated grit chamber with a defoaming system according to claim 1, characterized in that: Also includes: A sand collection device is arranged at the bottom of the sand settling area; The sand discharge pipe is connected with the sand collection device.

5. The aerated grit chamber with a defoaming system according to any one of claims 1 to 4, characterized in that: Also includes: A water flow direction sensor is disposed in the grit chamber body; a rotatable bracket is connected to the aeration system; The driving device is connected to the rotatable bracket; the control system is electrically connected to the water flow direction sensor, the driving device and the defoaming system, and automatically adjusts the direction of the aeration system and the scraping frequency of the defoaming system according to the detected water flow direction.

6. The aerated grit chamber with a defoaming system according to claim 2, characterized in that: The foam scraping device comprises: a driving motor, which is arranged at one end of the collecting tank; and a scraper, which is connected to the driving motor and can move back and forth in the collecting tank.

7. The aerated grit chamber with a defoaming system according to claim 1, characterized in that: The guide structure is a guide plate; the guide plate is arranged in an inclined shape, and its inclination angle ranges from 15° to 45°.

8. The aerated grit chamber with a defoaming system according to claim 2, characterized in that: The sliding seat is provided with a plurality of positioning holes at equal intervals, and the fixing device comprises a fastening bolt, and the fastening bolt passes through the positioning hole and is fixedly connected to the aeration pipe.

9. The aerated grit chamber with a defoaming system according to any one of claims 1 to 4, characterized in that: Also includes: A water quality stratification detection device, comprising a plurality of vertically distributed sensors, is disposed in the grit chamber body; An adaptive aeration control system, electrically connected to the water quality stratification detection device, the aeration system and the defoaming system; Among them, the adaptive aeration control system is based on the dissolved oxygen, turbidity and temperature data of different water layers detected by the water quality stratification detection device; when the dissolved oxygen in the corresponding water layer is lower than the threshold, the aeration intensity of the aeration pipe at that height is increased; when the increase in surface turbidity is detected, the operating frequency of the scraper device is increased; according to the change in water temperature, the overall aeration intensity is adjusted according to the preset curve.

10. The aerated grit chamber with a defoaming system according to claim 2, characterized in that: The bottom of the collecting tank is provided with an inclined surface, and the inclined surface is inclined toward the foam discharge port.

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