Online dissolved oxygen ratioing calibration apparatus

Abstract

The utility model relates to the field of on -line dissolved oxygen determination appearance calibration, disclose a kind of on -line dissolved oxygen comparison calibration equipment, including the closed solution pool being separated into bubbling pool and detection pool, bubbler, circulating pump, standard dissolved oxygen determination appearance, thermometer and control module. Bubbling pool cooperation bubbler preparation dissolved oxygen solution;Circulating pump drives solution circulation between bubbling pool and detection pool, and forms loop by overflow port;Detection pool built-in standard instrument real -time measurement and provide calibration standard value, thermometer auxiliary acquisition temperature data to revise calibration result. Control module receives data, and automatically controls circulating pump and prompts calibration. The present application can complete calibration on site quickly, substantially shorten the measurement period, improve calibration accuracy by real -time comparison and temperature correction, reduce standard liquid consumption and professional institution calibration cost, effectively meet the demand of large -scale equipment high frequency calibration.

Description

Technical Field

[0001] This utility model relates to the field of online dissolved oxygen meter calibration, specifically to an online dissolved oxygen comparison and calibration device. Background Technology

[0002] In fields such as environmental monitoring, wastewater treatment, aquaculture, and industrial process control, online dissolved oxygen meters are key devices for real-time monitoring of dissolved oxygen content in water bodies. The accuracy of their measurement data directly affects the reliability of water quality assessment, process control, and ecological environment analysis. As the application scope of online dissolved oxygen meters continues to expand and the number of devices increases dramatically, the need for their metrological calibration is becoming increasingly urgent.

[0003] Traditional calibration methods primarily rely on laboratory calibration, which typically requires disassembling the equipment and sending it to a professional metrology institution for calibration using standard solutions. However, a single round trip for calibration can take several weeks, resulting in a lengthy calibration cycle that cannot meet the demands of high-frequency on-site calibration. Furthermore, the service fees of professional institutions are high, and errors may be introduced during transportation, leading to numerous long-term risks. Laboratory standard solution methods use saturated dissolved oxygen water or chemical reagents to prepare standard solutions, but the preparation of standard solutions is cumbersome and requires strict control of conditions such as temperature and air pressure. In open environments, these conditions are easily affected by fluctuations in atmospheric oxygen partial pressure, temperature changes, and human operation, resulting in significant calibration errors. Standard solutions are also single-use, leading to high costs and waste liquid pollution.

[0004] Therefore, there is an urgent need to develop a device that can quickly and accurately calibrate online dissolved oxygen meters to overcome the shortcomings of traditional calibration methods, such as long cycles, high costs, and large errors, and to ensure the reliability and effectiveness of online monitoring data. Utility Model Content

[0005] This invention aims to provide an online dissolved oxygen comparison and calibration device. By integrating oxygen input, circulation drive, overflow circulation, and intelligent control functions in a closed solution tank, it achieves rapid and stable generation of dissolved oxygen solution and real-time comparison and calibration of the dissolved oxygen meter being calibrated.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An online dissolved oxygen comparison and calibration device includes: a sealed solution tank, wherein the sealed solution tank is internally divided into a bubbling tank and a detection tank by a partition; The bubbling tank includes a pure water injection port, a pressurized oxygen standard substance inlet port, and a bubbler. The bubbler is connected to the pressurized oxygen standard substance inlet port and is used to introduce the pressurized oxygen standard substance into the pure water in the form of bubbles to change the dissolved oxygen content of the pure water. The bubbling tank and the detection tank are connected through an overflow outlet, and the system also includes a circulation pump, the inlet of which is connected to the bubbling tank and the outlet of which is connected to the detection tank. The detection pool includes an inlet for a standard dissolved oxygen meter, an inlet for a dissolved oxygen meter to be calibrated, and an inlet for a thermometer, which are used to fix the standard dissolved oxygen meter, the dissolved oxygen meter to be calibrated, and the thermometer, respectively. It also includes a control module, which is electrically connected to the circulating pump, the standard dissolved oxygen meter, and the thermometer, respectively. It is used to receive data transmitted from the standard dissolved oxygen meter and the thermometer, control the start and stop of the circulating pump and the flow rate according to the set program, and also to provide calibration prompts.

[0007] The principle and advantages of this scheme are as follows: In practical application, a bubble pool and a detection pool are separated within a sealed solution tank. Pure water is injected into the bubble pool through the pure water inlet port, and pressurized oxygen standard material is introduced through the pressurized oxygen standard material inlet port. A bubbler dissolves the oxygen into the pure water in a bubbling manner, preparing a dissolved oxygen solution. A circulation pump transports the solution prepared in the bubble pool to the detection pool. When the solution in the detection pool reaches a certain volume, it overflows back to the bubble pool through the overflow port, forming a solution circulation and accelerating the uniform mixing of the solution. In the detection pool, a standard dissolved oxygen analyzer measures the dissolved oxygen content of the solution in real time, providing an accurate standard value; a thermometer measures the solution temperature, facilitating the lookup of the corresponding standard value using a saturated dissolved oxygen reference table; the control module receives data from the standard dissolved oxygen analyzer and the thermometer, and controls the start / stop and flow rate adjustment of the circulation pump according to a set program. When the dissolved oxygen content and temperature of the solution reach preset conditions, a calibration prompt is issued, realizing an automated calibration process.

[0008] This solution enables rapid on-site preparation and calibration of dissolved oxygen solutions, significantly shortening the metrology cycle and meeting the high-frequency calibration requirements of large-scale equipment. It provides standard values ​​through real-time measurements using a standard dissolved oxygen analyzer, and corrects for errors introduced by environmental factors and human operation using a saturated dissolved oxygen reference table, reducing the accuracy of calibration results. Solution circulation accelerates solution preparation, improves the uniformity of dissolved oxygen, and further enhances calibration accuracy. Simultaneously, it reduces the use of standard solutions and the calibration costs of professional institutions, achieving long-term cost optimization.

[0009] Preferably, as an improvement, the circulating pump is a peristaltic pump with adjustable flow rate.

[0010] Technical benefits: It facilitates the adjustment of pump flow rate, controls the speed at which the solution is injected from the bubbling tank area into the detection tank area, thereby controlling the solution circulation rate, accelerating solution preparation, and reducing the unevenness of dissolved oxygen in the solution.

[0011] Preferably, as an improvement, the overflow outlet is provided with a one-way valve.

[0012] Technical effect: Prevents the solution from flowing directly back from the bubbling tank to the detection tank, ensuring the uniqueness of the circulation direction.

[0013] Preferably, as an improvement, the bubbler is a porous titanium alloy or ceramic microporous aeration head with a pore size of 10-50 μm.

[0014] Technical benefits: It facilitates the formation of microbubbles with a diameter of ≤1 mm by a bubbler for pressurized oxygen standard substances, thereby improving oxygen dissolution efficiency and reducing solution disturbance.

[0015] Preferably, as an improvement, the sealed solution tank is made of stainless steel or polytetrafluoroethylene, and the inner wall of the sealed solution tank is coated with a hydrophobic coating.

[0016] Technical benefits: It helps reduce oxygen adsorption and solution contamination.

[0017] Preferably, as an improvement, the pressure of the pressurized oxygen standard material is greater than 4 MPa.

[0018] Technical benefits: Facilitates the provision of stable traffic output.

[0019] Preferably, as an improvement, the bottom of the detection pool is provided with a drain outlet, and a solenoid valve is provided at the drain outlet, the solenoid valve being controlled to open and close by a control module.

[0020] Technical benefits: Facilitates the discharge of waste liquid.

[0021] Preferably, as an improvement, it also includes a portable housing with shock-absorbing feet on the bottom and a handle on the top.

[0022] Technical benefits: Facilitates on-site relocation and deployment. Attached Figure Description

[0023] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model.

[0024] The reference numerals in the accompanying drawings of the instruction manual include: 1. Detection tank; 2. Bubbling tank; 3. Bubbler; 4. Overflow outlet; 5. Circulation pump; 6. Standard dissolved oxygen analyzer; 7. Dissolved oxygen analyzer under calibration; 8. Thermometer; 9. Pressurized oxygen standard substance. Detailed Implementation

[0025] The following detailed description illustrates the specific implementation method: The basic implementation examples are as follows: Figure 1 As shown: The online dissolved oxygen comparison and calibration equipment includes: a sealed solution tank, the sealed solution tank being made of stainless steel or polytetrafluoroethylene, and the inner wall of the sealed solution tank being coated with a hydrophobic coating to reduce oxygen adsorption and solution contamination.

[0026] The sealed solution pool is divided into a bubbling pool 2 and a detection pool 1 by a partition.

[0027] The bubbling tank 2 includes a pure water injection port, a pressurized oxygen standard substance inlet port, and a bubbler 3. The bubbler 3 is connected to the pressurized oxygen standard substance inlet port and is used to introduce the pressurized oxygen standard substance into the pure water in a bubbling form to change the dissolved oxygen content of the pure water. Specifically, the bubbling tank 2 also includes a pressure reducing valve and a flow controller. The flow controller is electrically connected to the control module, and the bubbler 3 is immersed in the pure water of the bubbling tank 2. The pressurized oxygen standard substance serves as the oxygen source, and the flow rate and pressure are controlled by the flow controller to ensure that it enters the system at a constant rate. The gas enters the liquid through the tiny holes in the bubbler 3. The holes disperse the gas into countless tiny bubbles, increasing the contact area between the gas and the liquid. When the bubbles enter the liquid, they gradually rise to the surface. During this process, the bubble surface area is large and the residence time is relatively long, giving oxygen molecules the opportunity to diffuse into the water, thereby increasing the dissolved oxygen content in the water. The smaller the bubbles, the larger the total surface area, and the higher the dissolution efficiency. In addition to directly increasing dissolved oxygen, the bubbling process also produces a certain stirring effect, promoting mixing inside the liquid, further enhancing the uniform distribution of oxygen, and avoiding local oversaturation or undersaturation.

[0028] During the bubbling process, higher temperatures reduce the water's ability to dissolve oxygen. In this embodiment, a constant temperature device is also installed around the outside of the solution pool to maintain the stability of the solution temperature inside the pool and avoid temperature fluctuations affecting the dissolved oxygen measurement and calibration results.

[0029] The bubbler is a porous titanium alloy or ceramic microporous aeration head with a pore size of 10-50μm, which facilitates the formation of microbubbles with a diameter ≤1 mm by pressurized oxygen standard substances through the bubbler, thereby improving oxygen dissolution efficiency and reducing solution disturbance.

[0030] The pressurized oxygen standard material has a pressure greater than 4 MPa, which helps to ensure the dissolution rate of oxygen in pure water and provide a stable flow output.

[0031] The bubbling tank 2 and the detection tank 1 are connected by an overflow port 4. When the solution in the detection tank reaches a certain volume, the solution flows back to the bubbling tank 2 through the overflow port 4. The overflow port is equipped with a one-way valve to prevent the solution from flowing directly back from the bubbling tank to the detection tank, ensuring the uniqueness of the circulation direction. A circulation pump 5 is also included, with its inlet connected to the bubbling tank 2 and its outlet connected to the detection tank 1; it is used to drive the solution to circulate between the bubbling tank 2 and the detection tank 1.

[0032] The detection pool 1 includes an inlet for a standard dissolved oxygen meter, an inlet for a dissolved oxygen meter to be calibrated, and an inlet for a thermometer, which are used to fix the standard dissolved oxygen meter 6, the dissolved oxygen meter to be calibrated 7, and the thermometer 8, respectively.

[0033] It also includes a control module, which is electrically connected to the circulating pump 5, the standard dissolved oxygen meter 6, and the thermometer 8. The control module receives data transmitted from the standard dissolved oxygen meter 6 and the thermometer 8, controls the start / stop and flow regulation of the circulating pump 5 according to a set program, and also provides calibration prompts. Specifically, the control module includes a data acquisition unit, a PID control unit, and a calibration algorithm unit. The data acquisition unit collects the dissolved oxygen value from the standard dissolved oxygen meter, the water temperature value from the thermometer, and the measured value from the dissolved oxygen meter being calibrated in real time. The PID control unit dynamically adjusts the flow controller opening and the rotation speed of the circulating pump 5 based on the deviation between the dissolved oxygen value and the target value. The calibration algorithm unit generates calibration coefficients through differential calculation based on the real-time data from the standard dissolved oxygen meter and the measured value from the dissolved oxygen meter being calibrated, and corrects the output signal of the dissolved oxygen meter being calibrated.

[0034] For easy on-site deployment, a portable casing is also included, with shock-absorbing feet at the bottom and a handle at the top. The bottom of the testing pool has a drain outlet equipped with a solenoid valve, which is controlled by a control module to facilitate waste liquid discharge. To reduce oxygen adsorption and solution contamination, the sealed solution pool is made of stainless steel or polytetrafluoroethylene, and its inner wall is coated with a hydrophobic coating.

[0035] In practical applications, pure water is injected into the bubbling tank through the pure water injection port, and then oxygen is injected through the pressurized oxygen standard substance inlet port. The dissolved oxygen content of the pure water is changed by the bubbler 3 until the target requirement is met. Then the circulation pump 5 is started to transport the solution from the bubbling tank 2 to the detection tank 1. When the liquid level reaches the overflow port 4, it automatically flows back, and the circulation ensures uniformity.

[0036] The standard dissolved oxygen analyzer 6 measures dissolved oxygen levels in real time, while the thermometer 8 measures water temperature. The control module automatically calculates the deviation based on a saturated dissolved oxygen reference table (e.g., theoretical value of 8.26 mg / L at 25℃). When the deviation meets the requirements (e.g., error ≤ ±0.05 mg / L for 5 consecutive measurements), a calibration prompt is triggered. The probe of the instrument to be calibrated is inserted into the detection cell to complete the comparison calibration. After calibration, the control module opens the drain solenoid valve, discharging the waste liquid into a dedicated recovery container, and the system automatically enters standby mode.

[0037] The above descriptions are merely embodiments of this utility model. Commonly known technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solution of this utility model. These modifications and improvements should also be considered within the scope of protection of this utility model, and will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. An online dissolved oxygen comparison and calibration device, characterized in that, include: A closed solution tank is internally divided into a bubbling tank and a detection tank by a partition. The bubbling tank includes a pure water injection port, a pressurized oxygen standard substance inlet port, and a bubbler. The bubbler is connected to the pressurized oxygen standard substance inlet port to introduce the pressurized oxygen standard substance into the pure water in a bubbling manner, thereby changing the dissolved oxygen content of the pure water. The bubbling tank and the detection tank are connected through an overflow outlet. The tank also includes a circulation pump, with its inlet connected to the bubbling tank and its outlet connected to the detection tank. The detection tank includes an inlet for a standard dissolved oxygen meter, an inlet for a dissolved oxygen meter under calibration, and a thermometer inlet, used to fix the standard dissolved oxygen meter, the dissolved oxygen meter under calibration, and the thermometer, respectively. The tank also includes a control module electrically connected to the circulation pump, the standard dissolved oxygen meter, and the thermometer, used to receive data transmitted from the standard dissolved oxygen meter and the thermometer, control the start / stop and flow rate adjustment of the circulation pump according to a set program, and provide calibration prompts.

2. The online dissolved oxygen comparison and calibration device according to claim 1, characterized in that: The circulating pump is a peristaltic pump with adjustable flow rate.

3. The online dissolved oxygen comparison and calibration device according to claim 1, characterized in that: The overflow outlet is equipped with a one-way valve.

4. The online dissolved oxygen comparison and calibration device according to claim 1, characterized in that: The bubbler is a porous titanium alloy or ceramic microporous aeration head with a pore size of 10-50μm.

5. The online dissolved oxygen comparison and calibration device according to claim 1, characterized in that: The sealed solution tank is made of stainless steel or polytetrafluoroethylene, and the inner wall of the sealed solution tank is coated with a hydrophobic coating.

6. The online dissolved oxygen comparison and calibration device according to claim 1, characterized in that: The pressure of the pressurized oxygen standard material is greater than 4 MPa.

7. The online dissolved oxygen comparison and calibration device according to claim 1, characterized in that: The bottom of the detection pool is equipped with a drain outlet, and a solenoid valve is installed at the drain outlet. The solenoid valve is controlled to open and close by the control module.

8. The online dissolved oxygen comparison and calibration device according to claim 1, characterized in that: It also includes a portable housing with shock-absorbing feet on the bottom and a handle on the top.

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