Liquid level automatic maintaining device for air floatation equipment

Abstract

The utility model discloses a kind of liquid level automatic maintenance devices of air floatation equipment, belong to sewage treatment equipment technical field.The device includes liquid level signal acquisition device, liquid level electric regulating device and control system.Liquid level signal acquisition device real-time monitoring air floatation pool liquid level;Control system exports control instruction according to the deviation of monitoring signal and set value;Liquid level electric regulating device receives instruction, drives electric actuator to act, and water weir plate is lifted by T type screw rod, to automatically regulate water flow, so that pool liquid level is stably maintained in preset optimal working range.The utility model solves the problem of traditional manual regulating mode lag, inaccuracy, realizes the closed-loop automatic control of liquid level, effectively improves the air floatation equipment anti-inflow fluctuation ability and the stability of operation, ensures good scum scraping effect and lower scum water content.

Description

Technical Field

[0001] This utility model belongs to the technical field of sewage treatment equipment and relates to an automatic liquid level maintenance device for an air flotation device. Background Technology

[0002] The scum removal rate and scum moisture content of the air flotation equipment are important indicators for measuring the effectiveness of air flotation and are one of the criteria for judging whether the effluent meets the standards.

[0003] In existing horizontal flow air flotation technology, the liquid level is adjusted manually by adjusting the height of the effluent weir plate to control the overall liquid level in the flotation tank. The conventional setting for this liquid level is 2-5 cm below the highest point of the scum trough. The liquid level affects the scum removal efficiency of the air flotation. A low liquid level makes it difficult to scrape scum into the scum trough, resulting in a lower scum removal rate; a high liquid level allows a large amount of water to enter the scum trough, leading to excessively high water content in the scum. Both of these situations negatively impact the operation of the air flotation system.

[0004] Currently, the liquid level in the dissolved air flotation tank is usually adjusted manually according to the operating conditions. During normal operation, fluctuations in the influent (unstable influent volume, sometimes large and sometimes small), untimely equipment inspection and observation, and failure to make timely adjustments to the effluent regulating weir plate often lead to the overall liquid level of the dissolved air flotation tank rising or falling compared to stable operation, resulting in the above-mentioned situation. Summary of the Invention

[0005] To address the aforementioned problems, this utility model provides an automatic liquid level maintenance device for an air flotation equipment. This device aims to overcome the problem of unstable liquid level in the tank caused by lag in manual adjustment, fluctuations in influent, and untimely observation, thereby avoiding a decrease in scum removal rate due to excessively low liquid level or an increase in scum moisture content due to excessively high liquid level, ultimately improving the overall treatment effect and operational stability of the air flotation equipment.

[0006] According to the technical solution of this utility model: an automatic liquid level maintaining device for an air flotation equipment, characterized in that it includes: A liquid level signal acquisition device is used to acquire liquid level signals in an air flotation tank. An electric liquid level regulating device is used to automatically adjust the height of the outlet weir plate according to the liquid level signal; The control system is used to receive the liquid level signal and control the operation of the electric liquid level regulating device to keep the liquid level in the flotation tank within a set range.

[0007] As a further improvement of this utility model, the liquid level signal acquisition device includes a hydrostatic liquid level gauge or a liquid level gauge with analog signal output.

[0008] As a further improvement of this utility model, the liquid level signal acquisition device is installed on the pool wall of the air flotation contact zone or air flotation separation zone.

[0009] As a further improvement of this utility model, the electric liquid level regulating device includes an electric actuator and a water outlet weir plate connected to the electric actuator.

[0010] As a further improvement of this utility model, the electric liquid level regulating device also includes a drive support and a T-shaped lead screw, wherein the T-shaped lead screw connects the electric actuator and the outlet weir plate.

[0011] As a further improvement of this utility model, the outlet weir plate is connected to the T-shaped lead screw via a pin.

[0012] As a further improvement of this utility model, the liquid level signal acquisition device also includes a bracket structure for mounting the liquid level gauge.

[0013] As a further improvement of this utility model, the support structure includes a level gauge hanging plate, a sleeve support, and U-bolts for fixing the protective sleeve.

[0014] As a further improvement of this utility model, the electric actuator can rotate forward or reverse to drive the outlet weir plate to rise or fall.

[0015] As a further improvement of this utility model, when the control system detects that the liquid level exceeds the set range, it sends an adjustment command to the electric liquid level adjustment device until the liquid level returns to the set range.

[0016] The technical advantages of this invention are as follows: The invention features a reasonable and ingenious structure. By installing a hydrostatic level gauge (or other level gauge with analog signal output) in the air flotation separation zone, the conventional manual adjustment of the level regulating weir plate is replaced with electric adjustment. Through signal feedback of the liquid level height within the air flotation separation zone, the electric effluent weir plate makes timely and accurate adjustments to its height. This ensures that a reasonable operating liquid level is maintained during normal operation of the air flotation system, improving the equipment's resistance to fluctuations and stability. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the original air flotation equipment's liquid level adjustment device.

[0018] Figure 2 This is a schematic diagram of the structure of this utility model.

[0019] Figure 3 This is a schematic diagram of a liquid level signal acquisition device.

[0020] Figure 4 This is a schematic diagram of an electric liquid level regulating device. Detailed Implementation

[0021] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings.

[0022] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. The described embodiments are merely 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 should fall within the protection scope of the present invention.

[0023] In the description of this utility model, it should be understood that the terms "upper", "lower", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0024] The core of this invention lies in providing an automatic liquid level maintenance device for air flotation equipment, aiming to solve the problems of unstable liquid level, poor scum scraping effect, and substandard scum moisture content or removal rate caused by the reliance on manual adjustment of the effluent weir plate in existing horizontal flow air flotation equipment. Through automated liquid level monitoring and adjustment, the air flotation tank is ensured to always maintain the optimal working liquid level.

[0025] like Figure 2-4 As shown, the present invention provides an automatic liquid level maintenance device for an air flotation equipment, which mainly includes: a liquid level signal acquisition device 1, a liquid level electric adjustment device 2, and a control system (not shown separately in the figure, usually a PLC, DCS or a dedicated controller).

[0026] The liquid level signal acquisition device 1 is used to acquire the liquid level height in the flotation tank, especially in the flotation contact area (or set in the separation area according to process requirements), in real time and accurately, and convert it into an electrical signal that can be recognized by the control system.

[0027] like Figure 3 As shown, the liquid level signal acquisition device 1 mainly consists of a liquid level gauge body, a mounting bracket, and a protective structure.

[0028] The liquid level gauge body is preferably a hydrostatic liquid level gauge 1.6. Of course, those skilled in the art will know that any liquid level gauge capable of outputting a continuous analog signal (such as a 4-20mA current signal or a 0-10V voltage signal), such as a radar liquid level gauge or an ultrasonic liquid level gauge, can be used here. The selection can be determined based on factors such as the specific characteristics of the medium, the installation environment, and the cost.

[0029] To stably mount the level gauge onto the pool wall 1.4, a mounting bracket structure is provided. This structure mainly includes a level gauge suspension plate 1.1 and a sleeve bracket 1.2. The level gauge suspension plate 1.1 is fixed to a suitable position on the top or side wall of the pool wall to suspend the level gauge 1.6. The sleeve bracket 1.2 is also fixed to the pool wall to provide support for the protective sleeve 1.3.

[0030] To protect the sensing element of the level gauge 1.6 from water flow impact, floating debris interference, or mechanical damage, a protective sleeve 1.3 is installed. This protective sleeve 1.3 is securely fixed to the sleeve support 1.2 using U-bolts 1.5. The sensing element of the level gauge 1.6 extends into this protective sleeve 1.3 for measurement. The bottom of the protective sleeve 1.3 is usually open or equipped with a filter to ensure communication between the water and the sensing element. The specific dimensions and materials (e.g., stainless steel, corrosion-resistant carbon steel) of each component (hanging plate 1.1, support 1.2, sleeve 1.3, bolts 1.5) need to be designed and selected based on the specific operating conditions, such as the pool size, the corrosiveness of the medium, and the weight of the level gauge.

[0031] The electric level regulating device 2 is used to receive instructions from the control system and automatically and accurately adjust the height of the outlet weir plate 2.7, thereby changing the water flow area of ​​the outlet and realizing level control.

[0032] like Figure 4 As shown, the electric liquid level regulating device 2 mainly includes a drive part and a weir plate regulating part.

[0033] The core of the drive system is an electric actuator 2.1 (such as an electric push rod, electric cylinder, or a worm gear mechanism driven by a motor). This actuator 2.1 is mounted on the clear water zone wall 2.4 of the flotation tank via a drive support 2.2. The drive support 2.2 is securely connected to the tank wall via fasteners 2.3 (such as bolts), providing a stable foundation for the entire adjustment device. The electric actuator 2.1 has forward and reverse rotation functions, corresponding to linear drive in two directions respectively.

[0034] The weir plate adjustment section transmits the linear motion of the electric actuator 2.1 to the outlet weir plate 2.7, and mainly includes a T-shaped lead screw 2.5 and the outlet weir plate 2.7. One end of the T-shaped lead screw 2.5 is connected to the output rod of the electric actuator 2.1, and the other end is hinged to the outlet weir plate 2.7 via a pin 2.6. This hinged connection (pin connection) can compensate for minor misalignments that may occur during installation or operation, ensuring smooth transmission and allowing the weir plate a certain degree of freedom of swing, preventing jamming. The outlet weir plate 2.7 is installed vertically at the outlet, and its up-and-down movement directly changes the height of the outlet weir plate. The specific parameters (such as the thrust / stroke of the actuator, lead screw diameter and pitch, and weir plate size) and forms (such as the type of actuator) of each component need to be determined according to the specific working conditions such as the size of the weir plate, the required adjustment force, and the adjustment speed.

[0035] The control system is usually integrated in the main control cabinet of the equipment. It receives the real-time simulated liquid level height signal from the liquid level signal acquisition device 1 and compares and judges the signal with the internally preset "normal working liquid level range" (usually set to 2-5cm below the highest point of the scum tank).

[0036] The automatic holding process of the entire device is as follows: 1. Signal acquisition: The hydrostatic level gauge 1.6 continuously measures the liquid level in the air flotation contact area and converts the liquid level height value into a continuous 4-20mA current signal, which is then transmitted to the control system.

[0037] 2. Judgment and decision-making: The internal program of the control system compares the current liquid level signal with the set value in real time.

[0038] If the current liquid level is higher than the upper limit of the set range, it indicates that the water level in the pool is too high, and there is a risk of too much clean water entering the scum tank. The control system then generates a "lower liquid level" adjustment command.

[0039] If the current liquid level is below the lower limit of the set range, it indicates that the water level in the tank is too low, which may make it difficult to remove scum. The control system then generates an adjustment command to "raise the liquid level".

[0040] If the liquid level is within the set range, it is considered normal and no action command is issued.

[0041] 3. Execution of Regulation: Upon receiving the "lower liquid level" command, the control system drives the electric actuator 2.1 to rotate forward (assuming it is in the forward lifting direction), which in turn drives the outlet weir plate 2.7 upward via the T-screw 2.5. As the weir plate height increases, the outlet flow area decreases, and the outflow rate in the pool is temporarily less than the inflow rate, causing the liquid level to gradually decrease.

[0042] When a "raise liquid level" command is received, the control system drives the electric actuator 2.1 to reverse, which in turn drives the outlet weir plate 2.7 downwards via the T-screw 2.5. The weir plate height decreases, the outlet flow area increases, and the water flow rate in the pool increases, causing the liquid level to gradually rise.

[0043] 4. Feedback and Holding: During the adjustment process, the liquid level signal acquisition device 1 continuously feeds back new liquid level values. The control system performs closed-loop control based on the feedback values ​​until the liquid level returns to the set normal operating range. Once the liquid level returns to the set range, the control system commands the electric actuator 2.1 to stop operating, and the outlet weir 2.7 is fixed at a new height, thus completing one adjustment cycle and achieving automatic, continuous, and precise maintenance of the liquid level.

[0044] Through the above method, this utility model successfully upgrades manual adjustment to automatic closed-loop control, which can respond instantly to changes in liquid level caused by factors such as fluctuations in influent volume, significantly improving the stability and anti-interference ability of the flotation equipment, and ensuring constant sludge scraping conditions and excellent flotation treatment effect.

[0045] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although this utility model has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the claims of this utility model.

Claims

1. An automatic liquid level maintaining device for an air flotation equipment, characterized in that, include: Liquid level signal acquisition device (1) is used to acquire liquid level signals in the flotation tank; An electric liquid level regulating device (2) is used to automatically adjust the height of the outlet weir plate (2.7) according to the liquid level signal; The control system is used to receive the liquid level signal and control the operation of the liquid level electric regulating device (2) so that the liquid level in the flotation tank is maintained within a set range.

2. The automatic liquid level maintaining device for the air flotation equipment as described in claim 1, characterized in that: The liquid level signal acquisition device (1) includes a hydrostatic liquid level gauge (1.6) or a liquid level gauge with analog signal output.

3. The automatic liquid level maintaining device for the air flotation equipment as described in claim 1, characterized in that: The liquid level signal acquisition device (1) is installed on the pool wall of the air flotation contact zone or air flotation separation zone.

4. The automatic liquid level maintaining device for the air flotation equipment as described in claim 1, characterized in that: The electric level regulating device (2) includes an electric actuator (2.1) and an outlet weir plate (2.7) connected to the electric actuator (2.1).

5. The automatic liquid level maintaining device for the air flotation equipment as described in claim 4, characterized in that: The electric level regulating device (2) further includes a drive support (2.2) and a T-shaped lead screw (2.5), which connects the electric actuator (2.1) and the outlet weir plate (2.7).

6. The automatic liquid level maintaining device for the air flotation equipment as described in claim 5, characterized in that: The outlet weir plate (2.7) is connected to the T-shaped lead screw (2.5) via a pin (2.6).

7. The automatic liquid level maintaining device for the air flotation equipment as described in any one of claims 1 to 6, characterized in that: The liquid level signal acquisition device (1) also includes a bracket structure for installing the liquid level gauge.

8. The automatic liquid level maintaining device for the air flotation equipment as described in claim 7, characterized in that: The support structure includes a level gauge hanging plate (1.1), a sleeve support (1.2), and U-bolts (1.5) for fixing the protective sleeve (1.3).

9. The automatic liquid level maintaining device for the air flotation equipment as described in any one of claims 4 to 6, characterized in that: The electric actuator (2.1) can rotate forward or backward to drive the outlet weir plate (2.7) to rise or fall.

10. The automatic liquid level maintaining device for the air flotation equipment as described in any one of claims 1 to 6, characterized in that: When the control system detects that the liquid level exceeds the set range, it sends an adjustment command to the electric liquid level regulating device (2) until the liquid level returns to the set range.

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