Accurate aeration rate control valve provided with flow velocity detection device and application of accurate aeration rate control valve

Abstract

The invention particularly relates to a regulating valve provided with a flow velocity detection device and capable of accurately controlling aeration flow, which is characterized by comprising a polygonal flow regulating valve and the flow velocity detection device, and the flow velocity detection device is arranged on the polygonal flow regulating valve. And a detection head of the flow velocity detection device is positioned in a valve body flow channel of the polygonal flow regulating valve. According to the accurate aeration rate control valve, the defects in the prior art are overcome, the aeration rate in an accurate aeration system can be accurately controlled, the requirements of all process stages for the aeration rate are completely met, and therefore energy can be further saved while the sewage treatment quality is guaranteed; and a good foundation is laid for comprehensive popularization of the accurate aeration system in the sewage treatment industry.

Description

Technical Field

[0001] The present invention belongs to the field of mechanical equipment, and relates to an aeration volume precision control valve provided with a flow rate detection device, and more specifically, to a regulating valve capable of precisely controlling the aeration volume flow rate in a sewage treatment scenario. Background Art

[0002] In the prior art, the aeration volume of the sewage treatment aeration system is generally controlled by adjusting the flow rate of each blower. Due to the limitation of the flow rate adjustment range of the blower itself, it cannot meet the synchronous adjustment requirements of the oxygen supply of the entire biochemical pool, resulting in power waste. With the further improvement of emission reduction and energy saving requirements, a precise aeration control system has been developed in China. The system integrates the automatic detection of the index content of the entire unit and the biochemical pool into an intelligent system. According to the detection results of the biochemical pool, the intelligent system will adjust the air supply of the unit in real time. The gas flow entering each biochemical pool is controlled by the flow control valve. According to the requirements of the precise aeration system, the control valve should meet the following technical requirements: (1) The pressure loss is not greater than 10mbar; (2) It has stable continuous adjustment characteristics within the set 0-100% stroke range. Therefore, it is imperative to develop a control valve dedicated to precise aeration.

[0003] In the current precise aeration system for sewage treatment, the regulation of aeration volume is achieved by controlling the opening of the regulating valve. Regulating valves generally use butterfly valves, diamond valves and aperture valves, among which the aperture valve has the highest control accuracy (i.e. "precision control valve for sewage treatment aeration volume", patent number ZL202321951819.7). Each aeration branch of the valve is equipped with an independent flow regulating valve and flow meter. The accuracy of the flow meter reading affects the distribution of branch aeration volume, thereby affecting the quality of sewage treatment. To ensure the measurement accuracy of the flow meter, the flow meter should be set on a relatively long straight pipe with a relatively stable flow field. Under normal circumstances, the straight pipe length is required to be not less than 20DN, where DN is the nominal diameter of the pipe. In actual projects, due to the influence of different site and pipeline structures, it is difficult to meet the above straight pipe length requirements, resulting in a large difference between the flow meter reading and the actual flow, which seriously affects the stability of water treatment quality and also limits the promotion and application of precise aeration systems in the sewage treatment industry. Summary of the invention

[0004] The present invention proposes an aeration volume precision control valve provided with a flow rate detection device, which solves the defects of the prior art and enables the aeration volume in the precision aeration system to be precisely controlled, fully meeting the aeration volume requirements of each process stage, thereby further saving energy while ensuring the quality of sewage treatment, and is suitable for all types of pipelines.

[0005] On the one hand, the aeration volume precision control valve of the present invention includes a polygonal flow regulating valve and a flow velocity detection device, wherein the flow velocity detection device is arranged on the polygonal flow regulating valve, and the detection head of the flow velocity detection device is located inside the valve body flow channel of the polygonal flow regulating valve.

[0006] In a preferred embodiment, the detection head of the flow velocity detection device is located at the center of the valve body flow channel, and the stability of the airflow in the center of the flow channel is used to ensure the accuracy of the data detected by the flow meter.

[0007] In a preferred embodiment, the flow rate detection device is a thermal flow meter.

[0008] The polygonal flow regulating valve of the present invention comprises: a valve body, a worm gear, a worm, a valve plate, and a slider. The valve body is composed of two left and right half valve bodies. The worm gear and the worm are arranged in the middle of the two half valve bodies. The worm gear and the boss on one of the half valve bodies form a positioning rotation pair, and the worm gear and the worm form a transmission pair. The side wall of the worm gear is provided with a plurality of rotation guide grooves distributed in an annular shape and at equal intervals. A plurality of sliders move in the rotation guide groove, and one end of the slider extends out of the rotation guide groove on the worm gear and is tightly engaged with the valve plate and extends into the translation guide groove provided on the valve body. The valve plate is tightly engaged with the slider. As the worm gear rotates, the plurality of valve plates open and close driven by the slider.

[0009] The number of the valve plates is the same as the number of the guide grooves on the valve body and the number of the rotating guide grooves on the worm gear, which is 3-12.

[0010] On the other hand, the aeration volume precision control valve of the present invention further includes a driving motor or a universal electric device for valves.

[0011] The drive motor can be a stepper motor, a servo motor or other motors.

[0012] In one embodiment, the drive motor of the present invention is directly connected to the polygonal flow regulating valve in a horizontal manner.

[0013] In another embodiment, the drive motor of the present invention is connected to the polygonal flow control valve in a horizontal manner or in a vertical manner through a transitional connection piece.

[0014] The transitional connection may be a steering transmission component, such as a right angle gearbox.

[0015] On the other hand, the aeration volume precision control valve of the present invention is also provided with an encoder or other positioner and a limit switch at one end of the worm. During the adjustment process, the encoder can detect the actual opening and convert it into a signal to be fed back to the electronic control system, thereby issuing a compensation instruction to compensate (correct) the valve opening and improve the adjustment accuracy. At the same time, since the encoder can dynamically feedback the actual opening of the valve adjustment and correct the opening error in time, this greatly reduces the positioning error of the valve caused by the manufacturing error of the drive device and the moving parts, and significantly improves the repeated positioning accuracy.

[0016] In another aspect, the aeration volume precision control valve of the present invention further includes a display screen, which is used for on-site debugging and observation.

[0017] On the other hand, the aeration volume precision control valve of the present invention further includes a protective cover, and the electrical components such as the driving motor, display screen, surge protector, terminal block, switching power supply and control circuit board are all arranged inside the protective cover.

[0018] Taking the thermal flow meter as an example, the working principle of the flow velocity detection device of the present invention is as follows. Two probes are arranged at one end of the detection head of the thermal calorimeter, one is a temperature measuring probe for measuring the gas temperature, and the other is a velocity measuring probe for measuring the gas flow velocity. The temperature measuring probe measures the gas temperature T1, and the velocity measuring probe obtains the corresponding temperature T2 through electrical heating, so that a temperature difference ΔT=T2-T1 is formed between the two probes. When gas passes through the patented control valve at a speed V, T2 will decrease. In order to keep ΔT constant, the velocity measuring probe must be continuously heated to keep T2 unchanged. When the airflow is stable, there is a corresponding heating power P, and the flow rate between the two probes of the flow meter can be obtained: q1=P÷(Cp*ΔT*ρ), Cp——isobaric specific heat capacity, ρ——gas density, so that the gas flow rate V=q1÷S1 can be calculated, S1——the flow channel area between the two probes, which is converted into the gas flow rate through the patented control valve q2=V*S2*k=k*q1*(S2÷S1)=k*P*S2÷(Cp*ΔT*ρ*S1), S2——control valve opening area, k——correction coefficient (measured in the laboratory).

[0019] Compared with the prior art, the technical solution of the present invention produces the following beneficial effects:

[0020] (1) High flow detection and control accuracy. The flow center of the polygonal regulating valve coincides with the center of the pipeline, and the flow meter probe is located in the flow channel, preferably on the center line of the flow channel. Since the flow field in the center of the flow channel is relatively stable, the data detected by the flow meter is also relatively stable. The flow data based on this is multiplied by the correction coefficient obtained by the experiment to obtain the actual flow with higher accuracy, which overcomes the defect that the original technology is easily affected by the unstable flow field and affects the flow accuracy.

[0021] (2) Compact structure and strong applicability. Since the flow meter and the regulating valve are integrated together, the structure is more compact and is no longer affected by the site and pipeline structure, and is suitable for all types of pipelines. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 It is a structural schematic diagram of an implementation scheme of the present invention. Figure 1 (A) is a schematic diagram showing the product of the embodiment in a closed state; Figure 1 (B) is a schematic diagram showing the product of this embodiment in a fully open state.

[0023] Figure 2 It is a partial cross-sectional view taken along line AA of the present invention.

[0024] Figure 3 It is a structural schematic diagram of another embodiment of the present invention. Figure 3 (A) is a schematic diagram showing the product of this embodiment driven by a driving motor in a closed state; Figure 3 (B) is a schematic diagram showing the product of this embodiment driven by a drive motor in a fully open state.

[0025] Figure 4 A schematic structural diagram of another embodiment of the present invention. Figure 4 A schematic diagram showing the product of this embodiment driven by a drive motor in a fully open state. Figure 4 No flow meter)

[0026] Figure 5 It is a structural schematic diagram of another embodiment of the present invention. Figure 5 (A) is a schematic diagram showing the embodiment product of the universal electric device connected to the valve in the closed state; Figure 5 (B) is a schematic diagram showing the product of this embodiment of the universal electric device connected to the valve in the fully open state.

[0027] Figure 6 The figure is a flow chart of the application of the present invention in precise aeration of sewage treatment.

[0028] Specific implementation scheme (the detection head labels of the thermal flowmeter in each figure are supplemented with labels in the embodiment)

[0029] 1) Combine the following Figure 1-2 , describing Example 1 of the present invention.

[0030] The present embodiment 1 provides an aeration volume precision control valve provided with a thermal flow meter, which mainly includes a polygonal flow regulating valve 20 and a thermal flow meter 10. The polygonal flow regulating valve 20 mainly includes a left half valve body 91, a right half valve body 92, a worm gear 5, a worm 4, a valve plate 8, a slider 19, etc.

[0031] like Figure 2As shown, the valve body is composed of a left half valve body 91 and a right half valve body 92, the worm wheel 5 is positioned on the boss of the right half valve body 92 and forms a rotating pair, the worm wheel 5 and the worm 4 form a transmission pair, a valve plate 8 is provided between the worm wheel 5 and the left half valve body 91, the slider 19 is tightly engaged with the valve plate 8, one end of the slider 19 extends into the corresponding translation guide groove 7 of the left half valve body 91, and the other end is provided with a bearing 18, the bearing 18 and the guide groove 6 on the worm wheel 5 form a kinematic pair; the thermal flow meter 10 is arranged on the side wall of the left half valve body 91, and the detection heads 101 and 102 of the flow meter are located at the center of the valve body flow channel.

[0032] The working principle of this embodiment is as follows: the worm 4 drives the worm wheel 5 to rotate, and the bearing 18 moves in the guide groove 6, forcing the slider 19 to drive the valve plate 8 to translate along the translation guide groove 7. Since the six valve plates 8 move synchronously, the hexagonal flow channel formed by the valve plates does not change its center while scaling in parallel (coinciding with the center line of the valve and the pipeline). The detection heads 101 and 102 of the thermal flow meter 10 are located in the center of the flow channel. The flow field stability in the center of the flow channel ensures the accuracy of the detected data, and is fed back to the electronic control system through the corresponding signal, forming a corresponding relationship between the signal and the valve opening, thereby realizing intelligent control of precise flow regulation.

[0033] 2) Combine the following Figure 2-3 , describing Example 2 of the present invention.

[0034] This embodiment 2 provides an aeration volume precision control valve equipped with a thermal flow meter, which mainly includes a drive motor 1, a polygonal flow regulating valve 20 and a thermal flow meter 10. The drive motor 1 is a stepper motor, a servo motor or other drive motors.

[0035] The specific structure of this embodiment 2 mainly includes a motor 1, a thermal flowmeter 10, a right-angle gearbox 2, a left half valve body 91, a right half valve body 92, a worm gear 5, a worm 4, a valve plate 8, a slider 19, an encoder 16, a handwheel component 3, a protective cover 17, a surge protector 14, a terminal block 15, a switching power supply 11, a circuit board 12, a display screen 13, etc.

[0036] like Figure 3 As shown, the motor 1 is indirectly connected to the worm 4 through the right-angle gearbox 2, so that the motor 1 and the worm are vertically connected, the horizontal end of the right-angle gearbox is connected to the handwheel component 3, and the other end of the worm is provided with an encoder 16; a protective cover 17 is provided at the upper end of the valve body, and the protective cover is provided with electrical components such as the motor 1, a surge protector 14, a terminal block 15, a switching power supply 11, a circuit board 12, and a display screen 13.

[0037] The working principle of this embodiment is as follows: the motor 1 indirectly drives the horizontal worm 4 through the right-angle gear box 2, and the worm 4 drives the worm wheel 5 to rotate, so that the rolling bearing 18 moves in the rotating guide groove 6, and the slider 19 drives the valve plate 8 to move along the translation guide groove 7. Since the six valve plates 8 move synchronously, the hexagonal flow channel composed of the valve plates 8 does not change its center while scaling in parallel, ensuring the stability of the flow field. The thermal flow meter 10 can measure the flow rate more accurately and feed back the signal to the electronic control system. The encoder 16 on the worm 4 can detect the actual number of revolutions of the worm 4 and feed back to the electronic control system, correct the valve opening, and ensure the accuracy of the flow regulation. The protective cover 17 can protect the electronic components from the adverse effects of the environment, ensuring the accuracy and safety of the action of the present invention, wherein the display screen 13 can facilitate on-site debugging and observation.

[0038] 3) Combine the following Figure 4 , describing Example 3 of the present invention.

[0039] like Figure 4 As shown, the motor 1 is indirectly connected to the worm 4 horizontally through the right-angle gearbox 2, the upper end (vertical end) of the right-angle gearbox is connected to the handwheel component 3, and the other end of the worm 4 is provided with an encoder 16.

[0040] The working principle of this embodiment is exactly the same as that of embodiment 2), except that the motor 1, the worm 4 and the right-angle gearbox 2 are installed in different positions. The hand wheel component 3 is mainly provided to facilitate the debugging and maintenance of the present invention.

[0041] 4) Combine the following Figure 5 , describing Example 4 of the present invention.

[0042] like Figure 5 As shown, this embodiment 4 provides an aeration volume precision control valve provided with a thermal flow meter, and the specific structure mainly includes a valve universal electric device 1, a polygonal flow regulating valve 20 and a thermal flow meter 10. Except for the valve universal electric device 1, the other structures are exactly the same as those of the embodiment 1.

[0043] The working principle of this embodiment is the same as that of Embodiment 2, except that the driving method is different. Embodiment 2 adopts direct motor drive, while this embodiment adopts a universal electric device to drive the regulating valve.

[0044] 5) Combine the following Figure 6 , illustrating the application of a specific embodiment of the present invention in sewage treatment.

[0045] The precise aeration system for sewage treatment mainly includes a master control system MCP, a blower, a main pipe, a branch pipe, a pressure gauge, a control valve of the present invention, an aeration tank, and a DO detection head (dissolved oxygen meter). The pressure gauge is arranged on the main pipe, the blower outlet is connected to the main pipe, and the control valve of the present invention is arranged on several branch pipes, and the outlet of the control valve is connected to the aeration pipeline system of the aeration tank. Figure 6 The application process of the present invention in precise aeration of sewage treatment is explained.

[0046] At each stage of the aeration process, the aeration amount is different, such as Figure 6 As shown, the total amount of oxygen required for each stage of the aeration tank is achieved by the master control cabinet MCP by controlling the guide vane opening of each blower of the blower unit. Even in the same process stage, the amount of oxygen required for each zone of the aeration tank (i.e., DO1, DO2, and DO3 positions) is different, and the distribution of aeration volume in each zone is achieved by adjusting the opening of the patented control valve. During the entire aeration process, the intelligent dissolved oxygen meter installed in each zone of the aeration tank will dynamically monitor the dissolved oxygen content (i.e., DO value) and regularly feed back the DO value signal to the master control cabinet MCP. The MCP then adjusts the opening of each blower and the patented control valve until the DO value meets the process requirements.

[0047] Figure 6 In the embodiment, the embodiment of the present invention mainly includes a polygonal flow control valve 20 and a thermal flow meter 10 (refer to Figure 1 ), the calorimeter 10 mainly has two types: constant power type and constant temperature difference type. This patent adopts a constant temperature difference flowmeter. Two probes are arranged at one end of the calorimeter detection head, one is a temperature probe 101 for measuring the gas temperature, and the other is a velocity probe 102 for measuring the gas flow rate. The temperature probe 101 measures the gas temperature T1, and the velocity probe 102 obtains the corresponding temperature T2 (T2>T1) through electrical heating. In this way, a temperature difference ΔT=T2-T1 is formed between the two probes. When the gas velocity V passes through the control valve of this patent, T2 will decrease. In order to keep ΔT constant, the velocity probe 102 must be continuously heated to keep T2 constant. When the airflow is stable, With the corresponding heating power P, the flow rate q1=P÷(Cp*ΔT*ρ) between the two probes of the flow meter can be obtained, Cp is isobaric specific heat capacity, ρ is gas density, so the gas flow rate V=q1÷S1 can be calculated, S1 is the flow channel area between the two probes, and converted into the gas flow rate q2=V*S2*k=k*q1*(S2÷÷÷÷S1)=k*P*S2÷(Cp*ΔT*ρ*S1) through the control valve of this patent, S2 is the opening area of ​​the control valve, k is the correction coefficient (measured in the laboratory).

[0048] In engineering applications ( Figure 6), when the master control cabinet MCP receives the D0 value signal, it will automatically analyze and calculate the opening area S2 of the control valve and the heating power P of the flow meter speed probe, and instruct the patented control valve to operate through an electrical signal, thereby realizing intelligent control of the flow.

[0049] It can be seen that the precise aeration process is to dynamically adjust the aeration volume according to the real-time monitoring data of the DO value in each process stage. It is a process of intelligent linkage between the blower and the patented control valve. The blower group controls the total aeration volume in each stage, and the control valve group is responsible for accurately allocating the aeration volume in each location and can realize real-time adjustment, thereby improving the aeration utilization rate and achieving the purpose of energy saving.

[0050] To sum up, the technical ideas and solutions of the present invention can be applied to any technical field that requires aeration flow regulation and control, including but not limited to sewage treatment, energy conservation and environmental protection, etc.; on the other hand, the technical ideas and solutions of the present invention cover a variety of implementation methods, which are difficult to list one by one through the embodiments of the present invention. All local changes or modifications made to the implementation methods of the present invention are still covered by the technical solutions of the present invention.

Claims

1. A precise aeration control valve, characterized in that It comprises a polygonal flow regulating valve and a flow velocity detection device. The flow velocity detection device is arranged on the polygonal flow regulating valve. The detection head of the flow velocity detection device is located inside the flow channel of the valve body of the polygonal flow regulating valve.

2. According to the aeration volume precision control valve of claim 1, the detection head of the flow rate detection device is located at the center of the valve body flow channel.

3. According to the aeration volume precision control valve of claim 1, the flow rate detection device is a thermal flow meter.

4. The aeration volume precision control valve according to claim 1, wherein the polygonal flow regulating valve comprises: A valve body, a worm gear, a worm, a valve plate and a slider, wherein the valve body is composed of two left and right half valve bodies, the worm gear and the worm are arranged in the middle of the two half valve bodies, the worm gear and the boss on one of the half valve bodies form a positioning rotation pair, and the worm gear and the worm form a transmission pair; a plurality of rotation guide grooves equidistantly distributed in an annular shape are provided on the side wall of the worm gear; a plurality of sliders move in the rotation guide groove, and one end of the slider extends out of the rotation guide groove on the worm gear and is tightly engaged with the valve plate and extends into the translation guide groove provided on the valve body, the valve plate is tightly engaged with the slider, and as the worm gear rotates, the plurality of valve plates open and close driven by the slider.

5. The aeration volume precision control valve according to claim 1, characterized in that Also included are drive motors or general electric devices for valves.

6. The aeration volume precision control valve according to claim 5, characterized in that The driving motor is a stepping motor, a servo motor or other motors.

7. According to the aeration volume precision control valve of claim 6, the drive motor is directly connected to the polygonal flow regulating valve in a horizontal manner, or the drive motor is connected to the polygonal flow regulating valve in a horizontal manner or in a vertical manner through a transitional connection.

8. The aeration volume precision control valve according to claim 7, wherein the transitional connection piece is a steering transmission component, such as a right-angle gear.

9. According to the aeration volume precision control valve of claim 4, one end of the worm is provided with an encoder or other positioner and a limit switch.

10. The aeration volume precision control valve according to claim 4, wherein the number of the valve plates is the same as the number of the guide grooves on the valve body and the number of the rotating guide grooves on the worm gear, which is 3-12.

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