Remote distributed sampling and sample reserving system and sampling method

Abstract

The invention provides a remote distributed sampling and sample reserving system and a sampling method.The system comprises a plurality of sampling and sample reserving units, the sampling ends of the sampling and sample reserving units are connected to target sampling pools of different sampled fluids, and each sampling and sample reserving unit comprises a sample injection cabin, a liquid inlet pipe, a liquid drainage pipe, an air pressure adjusting assembly, a sample reserving assembly and a pipeline control valve; the air pressure adjusting assembly is used for forming a negative pressure state or a normal pressure state in the sampling cabin, and the negative pressure state is used for extracting sampled fluid or extracting residual fluid in the liquid discharging pipe after sampling is completed; and the sample reserving assembly is used for collecting the collected fluid. According to the invention, the plurality of sampling and sample reserving units are arranged, so that multi-point simultaneous sampling to the plurality of sampling and sample reserving units, multi-point sampling to different sample reserving cups of one sampling and sample reserving unit at different time periods, and single-point sampling to different sample reserving cups of one sampling and sample reserving unit at different time periods can be realized; and samples can be automatically reserved after sampling, so that the sampling efficiency is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of fluid sampling equipment technology, and in particular to a remote distributed sampling and retention system and sampling method. Background Technology

[0002] In scenarios such as large municipal wastewater treatment plants, electroplating wastewater treatment stations with diverse wastewater types, and industrial park wastewater treatment plants employing separate wastewater treatment processes, it is often necessary to collect wastewater samples from multiple locations frequently. Wastewater quality must be monitored in real time through online or manual water quality testing to provide reliable data support for wastewater treatment process adjustments and water quality compliance monitoring. Currently, the mainstream fluid sampling equipment on the market is mainly based on traditional positive pressure pump sampling systems. However, these systems have many insurmountable functional defects when adapting to the aforementioned application scenarios, failing to meet practical application requirements.

[0003] First, traditional positive pressure pump sampling systems struggle to achieve simultaneous multi-point sampling. These systems typically employ a "one-to-one" single-point sampling architecture. Even when attempting to expand multi-point sampling capabilities by switching pipelines using solenoid valves, they can only achieve sequential sampling between points, failing to meet the core requirement of simultaneous collection of multiple water samples. In scenarios such as industrial parks where wastewater is treated in a separate, differentiated manner, synchronous monitoring of water quality across different diversion pipelines is crucial. Sequential sampling leads to discrepancies in sampling times at each point, failing to reflect the overall water quality at any given time, thus impacting the timeliness and accuracy of process adjustments.

[0004] Secondly, traditional positive pressure pump sampling systems have poor sampling accuracy, which can easily lead to sample contamination or concentration distortion. On the one hand, residual liquid from previous batches of samples can easily remain inside the sampling pump and in the sampling pipeline, and most systems are not equipped with effective tap water backwashing facilities. On the other hand, even if some systems are equipped with backwashing facilities, the clean water remaining in the pipeline after backwashing will dilute the wastewater samples collected in the next batch, resulting in a decrease in sample concentration and an inability to accurately reflect the actual water quality.

[0005] Furthermore, traditional positive pressure pump sampling systems have low sampling efficiency and pose a risk of secondary pollution. The pipelines used in such systems are usually rigid pipes with specifications of DN15~DN32. Due to the limitations of pipeline structure and pumping method, only about 1% of the extracted liquid can be used for testing or sampling. If the large amount of excess liquid is not properly disposed of, it is very easy to leak or be discharged at will, causing secondary pollution.

[0006] In summary, the market urgently needs a new type of fully automatic sampling device that can simultaneously sample from multiple points, automatically retain samples after sampling, prevent secondary pollution, use small sampling pipe diameters, achieve high utilization of sampling fluid volume, and ensure that there is no residual sampling liquid or backwash water from the previous batch in the single sampling pipeline system. Summary of the Invention

[0007] The purpose of this invention is to overcome the problems of existing traditional positive pressure pump sampling systems, such as lack of simultaneous multi-point sampling capability, poor sampling accuracy, susceptibility to sample contamination by residual liquid or backwash liquid, low sampling efficiency, and high risk of secondary contamination. This invention provides a remote distributed sampling and retention system and method that enables simultaneous multi-point sampling, automatic sample retention after sampling, thorough removal of residual liquid and backwash water from previous batches in the pipeline, effectively avoids secondary contamination, adopts a small sampling pipe diameter design and improves the utilization rate of sampling fluid volume, and reduces manual intervention and operating costs.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a remote distributed sampling and retention system, characterized in that it includes a plurality of sampling and retention units, each of the sampling and retention units being an independent sampling fluid loop structure, the sampling end of each of the sampling and retention units being connected to different target sampling pools of the sampled fluid, and a single sampling and retention unit comprising: The sample inlet chamber is used to temporarily store the sampled fluid. The inlet pipe is connected at one end to the sample inlet chamber and at least one target sampling cell at the other end. The drain pipe has a sampling input end connected to the sample inlet chamber at one end and a sampling output end at the other end. The pressure regulating component is connected to the sample injection chamber to create a negative pressure or normal pressure state in the sample injection chamber and to achieve switching between at least two states. The negative pressure state is used to extract the sampled fluid or to extract the residual fluid in the drain pipe after sampling. The normal pressure state is used to release pressure after the negative pressure state is applied. A sample retention assembly is located below the sampling output end of the drain pipe for collecting the sampled fluid; and pipeline control valves are respectively installed on the inlet pipe, the drain pipe, and the pressure regulating assembly.

[0009] Furthermore, the pressure regulating component includes an atmospheric pressure pipeline and a negative pressure pipeline. The atmospheric pressure pipeline is connected to the atmosphere, and the negative pressure pipeline is connected to a negative pressure gas source. The atmospheric pressure pipeline and the negative pressure pipeline are connected in parallel and then connected to the sample injection chamber through the same gas pipe, or the atmospheric pressure pipeline and the negative pressure pipeline are connected to the sample injection chamber through different gas pipes.

[0010] Furthermore, the pressure regulating component also includes a positive pressure pipeline for creating a positive pressure state in the sample inlet chamber. The positive pressure state is used to output the sampled fluid to the sampling output end of the drain pipe or to return excess sampled fluid to the target sampling pool. The positive pressure pipeline is connected to a high-pressure gas source.

[0011] Furthermore, each of the sampling and retention units also includes a cleaning component disposed within the sample inlet chamber for cleaning the interior of the sample inlet chamber.

[0012] Furthermore, a waste sample container for collecting waste liquid is provided below the sampling output end of the drain pipe.

[0013] The present invention also provides a sampling method using the above-mentioned remote distributed sampling and retention system, comprising the following steps: Step 1: Activate the air pressure regulating component to bring the sample injection chamber to a negative pressure state; Step 2: Open the inlet tube and temporarily store the collected fluid in the sample injection chamber; Step 3: Activate the air pressure regulating component to bring the sample injection chamber to atmospheric pressure. Step 4: Open the drain pipe to distribute the fluid to the sample retention component to complete the sample retention; Step 5: Open the inlet pipe and drain the excess fluid back into the target sampling cell.

[0014] The beneficial effects of this invention are: 1. Multi-point sampling to meet complex monitoring needs: This invention, through the design of multiple parallel and independent sampling and retention units, can realize simultaneous sampling of sewage at multiple points, accurately obtain the overall water quality at the same time point, and also realize sampling from multiple points at different times to different retention cups of a single sampling and retention unit, as well as sampling from a single point at different times to different retention cups of a single sampling and retention unit. It is suitable for complex scenarios such as the separate flow of sewage in industrial parks and the monitoring of multiple structures in large municipal sewage treatment plants, which greatly improves sampling efficiency and reduces the safety risks of operators coming into contact with toxic and harmful sewage.

[0015] 2. Precise and contamination-free sampling ensures reliable test results: Through negative pressure pipeline suction, cleaning component cleaning, and positive pressure pipeline discharge and purging functions, residual liquid in the pipeline and sample inlet chamber can be thoroughly removed, avoiding contamination from previous batches and dilution of samples by backwash water. This fundamentally eliminates cross-contamination and concentration distortion, ensuring the authenticity of samples and the reliability of test data. In addition, the atmospheric pressure state is used for transition when switching between positive and negative pressure states, avoiding disturbance of the sampled fluid caused by sudden pressure changes.

[0016] 3. High fluid utilization rate and prevention of secondary pollution: Negative pressure suction for wastewater collection is compatible with small-diameter pipeline designs, improving fluid utilization. The collected fluid is temporarily stored in the sample inlet chamber. After collection, excess samples and cleaning waste can be returned to the target sampling pool, completely solving the problems of fluid waste and secondary pollution in traditional systems, and complying with environmental regulations. In addition, the sample retention component can accurately distribute multiple samples and can be directly connected to online detection equipment, meeting the requirements of a fully closed-loop automated design. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments will be briefly described below.

[0018] Figure 1 This is a schematic diagram of the overall structure of Embodiment 1 of the present invention.

[0019] Figure 2 This is a schematic diagram of the cabinet structure of Embodiment 1 of the present invention.

[0020] Figure 3 This is a schematic diagram of the cabinet assembly according to Embodiment 1 of the present invention.

[0021] Figure 4 This is a schematic diagram of the overall structure of Embodiment 2 of the present invention.

[0022] Explanation of reference numerals in the attached figures: 1. Sampling and retention unit; 2. Target sampling pool; 3. Sample inlet chamber; 4. Liquid inlet pipe; 5. Liquid outlet pipe; 501. Sampling output end; 6. Atmospheric pressure pipeline; 7. Positive pressure pipeline; 8. Negative pressure pipeline; 9. Cleaning nozzle; 10. Pipeline control valve; 11. Gas pipe; 12. Retention container; 1201. Conical funnel; 13. First level gauge; 14. Second level gauge; 15. Pressure sensor; 16. Guide rail; 17. Drive component; 18. Air compressor; 19. Vacuum pump; 20. Negative pressure gas tank; 21. Positive pressure gas tank; 22. Check valve; 23. Water supply pipeline; 24. Sampling pipeline; 25. Control unit; 26. Cabinet; 27. Wiring compartment; 28. Retention compartment; 29. ​​Valve compartment; 30. Waste sample container. Detailed Implementation

[0023] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0024] Example 1: like Figure 1As shown in the figure, this embodiment of a remote distributed sampling and retention system includes several sampling and retention units 1 arranged in parallel. Each sampling and retention unit 1 has an independent fluid loop structure and corresponds to different target sampling pools 2 (such as multiple sewage pools in environmental monitoring, multiple reactor discharge pools in industrial production, etc.). In this embodiment, one sampling and retention unit 1 corresponds to one target sampling pool 2. By setting up multiple sampling and retention units 1 in parallel, sampling can be achieved from multiple target sampling pools 2, meeting the needs of multi-point sampling. A single sampling and retention unit 1 includes a sample inlet chamber 3, a liquid inlet pipe 4, a liquid outlet pipe 5, a pressure regulating component, a cleaning component, a sample retention component, and several pipeline control valves 10. The sample inlet chamber 3 is used to temporarily store the sampled fluid. The liquid inlet pipe 4 is used to transport the fluid from the target sampling pool 2 to the sample inlet chamber 3. The air pressure regulating component adjusts the air pressure inside the sample inlet chamber 3 to achieve the intake and discharge of the fluid. The liquid outlet pipe 5 is used to distribute the sampled fluid temporarily stored in the sample inlet chamber 3 to the sample retention component. The cleaning component is used to clean the inner wall of the sample inlet chamber 3. Several pipeline control valves 10 are used to control the opening and closing of each pipeline.

[0025] The sample inlet chamber 3 has a sealed cavity made of stainless steel, providing excellent sealing and corrosion resistance. The volume of the sample inlet chamber 3 is designed according to actual sampling requirements. A first level gauge 13, a second level gauge 14, and a pressure sensor 15 are fixedly installed on the inner wall of the sample inlet chamber 3. Both the first level gauge 13 and the second level gauge 14 are float-type level gauges. The height of the first level gauge 13 matches the rated fluid capacity required for one sampling. When the fluid in the sample inlet chamber 3 reaches the height of the first level gauge 13, it indicates that the sampling volume has reached the rated value, and the sample inlet chamber 3 stops inputting fluid. The height of the second level gauge 14 is higher than that of the first level gauge 13. When the fluid reaches the height of the second level gauge 14, it indicates a malfunction in the first level gauge 13 or a certain pipeline control valve 10, triggering a fault alarm. In this embodiment, the pressure sensor 15 is located above the second level gauge 14, near the top of the sample inlet chamber 3. The pressure sensor 15 is a diffused silicon pressure sensor used to monitor the air pressure inside the sample inlet chamber 3 in real time. In another embodiment, the pressure sensor 15 may also be disposed on the pipeline of the air pressure regulating assembly.

[0026] Both the inlet pipe 4 and the outlet pipe 5 are made of corrosion-resistant plastic pipes, possessing excellent corrosion resistance and flexibility. One end of the inlet pipe 4 is connected to the bottom of the sample injection chamber 3 via a flange connection, and this end of the inlet pipe 4 extends upward into the interior of the sample injection chamber 3, bending to form an inverted U-shaped structure, with its outlet extending downward to the bottom of the sample injection chamber 3. The other end of the inlet pipe 4 is connected to the target sampling cell 2 via the sampling pipeline 24. The inverted U-shaped structure design plays a crucial role: First, it creates a liquid seal effect. When the sample inlet chamber 3 is filled with fluid or cleaning solution, the inverted U-shaped pipe section can retain some liquid, preventing gas in the sample inlet chamber 3 from flowing back into the target sampling pool 2 through the liquid inlet pipe 4. This ensures stable gas pressure in the sample inlet chamber during sampling and prevents excessive backflow of sewage into the target sampling pool due to negative pressure. Second, it guides the directional flow of fluid. With the outlet facing downwards and directly opposite the bottom of the sample inlet chamber 3, the sucked-in fluid can fall smoothly into the sample inlet chamber, avoiding fluid splashing that could cause errors in the level gauge. It also reduces the impact of fluid on the inner wall of the sample inlet chamber 3, lowering the risk of residual adhesion. One end of the drain pipe 5 is connected to the lower side wall of the sample inlet chamber 3, serving as the sampling input end, while the other end is the sampling output end 501.

[0027] The pressure regulation assembly includes an atmospheric pressure line 6, a positive pressure line 7, a negative pressure line 8, and a gas pipe 11. All three lines are made of stainless steel. One end of the atmospheric pressure line 6 is connected to the atmosphere, and the other end is connected to the gas pipe 11. One end of the positive pressure line 7 is connected to a high-pressure gas source, and the other end is connected to the gas pipe 11. One end of the negative pressure line 8 is connected to a negative pressure gas source, and the other end is connected to the gas pipe 11. The atmospheric pressure line 6, positive pressure line 7, and negative pressure line 8 are connected in parallel and then connected to the sample injection chamber 3 via the same gas pipe 11, achieving centralized pressure regulation within the sample injection chamber 3. This also simplifies the piping structure, improves the compactness and rationality of the overall equipment layout, and reduces installation and maintenance costs. Alternatively, depending on the piping layout, the atmospheric pressure line 6, positive pressure line 7, and negative pressure line 8 can be connected to the sample injection chamber 3 via separate pipes.

[0028] In this embodiment, the high-pressure gas source and the negative-pressure gas source are provided by independent devices. The high-pressure gas source is an air compressor 18 located at the far end of the positive pressure pipeline 7, and the negative-pressure gas source is a vacuum pump 19 located at the far end of the negative pressure pipeline 8. The exhaust end of the air compressor 18 is connected to a positive pressure gas tank 21. The intake end of the vacuum pump 19 is connected to a negative pressure gas tank 20, and a check valve 22 is provided at the exhaust end of the vacuum pump 19. In another embodiment, the high-pressure gas source and the negative-pressure gas source can be provided by the same vacuum pump 19. The intake end of the vacuum pump 19 is connected to the negative pressure pipeline 8 through the negative pressure gas tank 20, and the exhaust end of the vacuum pump 19 is connected in sequence to the check valve 22, the positive pressure gas tank 21, and the positive pressure pipeline 7. By discharging the gas in the negative pressure gas tank 20 into the positive pressure gas tank 21, gas circulation is achieved, and both positive and negative pressure gas sources are generated simultaneously. This integrated solution eliminates the need for an additional air compressor, significantly simplifying equipment structure, reducing floor space, and lowering energy consumption, making it more suitable for wastewater treatment scenarios with limited space.

[0029] The cleaning assembly includes a cleaning nozzle 9 and a water supply line 23. The cleaning nozzle 9 is an atomizing nozzle, located at the top inside the sample injection chamber 3, facing the inner wall and bottom of the sample injection chamber 3, enabling all-round cleaning of the inside of the sample injection chamber 3; one end of the water supply line 23 is connected to an external tap water source, and the other end is connected to the cleaning nozzle 9, used to provide tap water cleaning solution to the cleaning nozzle 9.

[0030] The sample retention assembly is located below the sampling output end 501 of the drain pipe 5 and includes several sample retention containers 12 and a driving mechanism. The sample retention containers 12 are arranged in an array, each using a transparent glass cup with a capacity of 500 mL. The driving mechanism is a planar two-dimensional linear motion module, including two orthogonally arranged guide rails 16 on a horizontal plane and a driving component 17 that slides along the guide rails. The driving component 17 is a slider driven by a servo motor. The slider is fixedly connected to the sampling output end 501 of the drain pipe 5. Driven by the servo motor, the slider moves along the two guide rails 16, thereby moving the sampling output end 501 directly above the different sample retention containers 12, thus distributing the fluid to the different sample retention containers 12. It should be noted that the driving mechanism can also be connected to the sample retention containers 12 via a tray, and the above fluid distribution function can be achieved by driving the tray to move the sample retention containers 12.

[0031] Several pipeline control valves 10 are respectively installed on the inlet pipe 4, the outlet pipe 5, the atmospheric pressure pipeline 6, the positive pressure pipeline 7, the negative pressure pipeline 8, and the tap water pipeline 23. They are electromagnetic reversing valves, which have the characteristics of fast response speed, good sealing performance, and long service life.

[0032] Each sampling and retention unit 1 in this embodiment also includes a control unit 25. The control unit 25 adopts a PLC controller and is connected to each pipeline control valve 10, air compressor 18, vacuum pump 19, drive mechanism, first liquid level gauge 13, second liquid level gauge 14, and pressure sensor 15 respectively. It is used to receive the detection signals from the first liquid level gauge 13, second liquid level gauge 14, and pressure sensor 15, and output control signals to each pipeline control valve 10, air compressor 18, vacuum pump 19, and drive mechanism to realize the automated control of the entire process of sampling, retention, and cleaning.

[0033] In addition, such as Figure 2 As shown, each sampling and retention unit 1 is equipped with a cabinet 26, which has four compartments: a sample inlet compartment 3, a wiring compartment 27, a sample retention compartment 28, and a valve compartment 29. The sample inlet compartment 3 is used to install the liquid inlet pipe 4, the air pipe 11, the cleaning nozzle 9, the first level gauge 13, the second level gauge 14, and the pressure sensor 15; the wiring compartment 27 is used to install the drive mechanism, the control unit 25, and the various circuit connection wires; the sample retention compartment 28 is used to accommodate the sample retention container 12 and the sampling output end 501 of the drain pipe 5; the valve compartment 29 is used to install and arrange the various pipelines and the pipeline control valves 10. The cabinets 26 of the sampling and retention unit 1 can be combined and installed according to the actual sampling target point requirements to achieve multi-point sampling, such as... Figure 3 The diagram shows nine sets of cabinets (26 combinations), which can be used to sample nine target sampling pools (2).

[0034] In this embodiment, the sampling method of the above-mentioned remote distributed sampling system specifically includes the following steps: Step 1: Impress the sample injection chamber 3. The control unit 25 sends a control signal to close the pipeline control valve 10 on the atmospheric pressure pipeline 6 and open the pipeline control valve 10 and vacuum pump 19 on the negative pressure pipeline 8. The pressure sensor 15 monitors the air pressure in the sample injection chamber 3 in real time. When the air pressure reaches the set target negative pressure value, the pressure sensor 15 feeds back the signal to the control unit 25. The control unit 25 then closes the vacuum pump 19 and the pipeline control valve 10 on the negative pressure pipeline 8, thus completing the establishment of negative pressure in the sample injection chamber 3.

[0035] Step 2: Fluid is drawn into the sample inlet chamber 3. The control unit 25 opens the pipeline control valve 10 on the inlet pipe 4. Under the negative pressure inside the sample inlet chamber 3, the fluid in the target sampling pool 2 is drawn into the sample inlet chamber 3 through the inlet pipe 4. The first level gauge 13 monitors the fluid level in the sample inlet chamber 3 in real time. When the level reaches the height of the first level gauge 13, the first level gauge 13 sends a signal to the control unit 25, and the control unit 25 immediately closes the pipeline control valve 10 on the inlet pipe 4, completing the quantitative fluid aspiration. If oversampling occurs (due to a malfunction of the first level gauge 13 or the pipeline control valve 10 on the inlet pipe 4), when the level reaches the height of the second level gauge 14, the second level gauge 14 triggers a fault alarm, reminding personnel to troubleshoot the fault.

[0036] Step 3: The sample injection chamber 3 is restored to atmospheric pressure. The control unit 25 opens the pipeline control valve 10 on the atmospheric pressure pipeline 6, and the air pressure in the sample injection chamber 3 gradually equalizes with the atmosphere. When the pressure sensor 15 detects that the air pressure has returned to atmospheric pressure (0 MPa), it sends a feedback signal to the control unit 25, which then closes the pipeline control valve 10 on the atmospheric pressure pipeline 6. This step prevents fluid splashing due to sudden pressure changes during subsequent positive pressure drainage, ensuring a stable drainage process.

[0037] Step 4: Establish positive pressure in sample injection chamber 3. Control unit 25 opens pipeline control valve 10 and air compressor 18 on positive pressure line 7 to introduce high-pressure gas into sample injection chamber 3; pressure sensor 15 monitors the air pressure in real time, and when the air pressure reaches the set target positive pressure value, it sends a feedback signal to control unit 25, which then closes air compressor 18 and pipeline control valve 10 on positive pressure line 7 to complete the establishment of positive pressure.

[0038] Step 5: Automatic Sample Retention. The control unit 25 sends a control signal to the drive mechanism based on the preset position of the sample container 12. The servo motor drives the slider to move along the guide rail 16, moving the sampling output end 501 of the drain pipe 5 directly above the target sample container 12. The control unit 25 opens the pipeline control valve 10 on the drain pipe 5, allowing the fluid in the sample inlet chamber 3 to be discharged from the sampling output end 501 through the drain pipe 5 under positive pressure and flow into the target sample container 12. The required fluid volume for sample retention can be controlled by the opening time of the pipeline control valve 10 on the drain pipe 5. When sample retention is complete, the control unit 25 closes the pipeline control valve 10 on the drain pipe 5. If multiple samples are needed, this step is repeated, with the drive mechanism moving the sampling output end 501 to the next sample container 12 position and the drain pipe 5 opening again to complete the sample retention.

[0039] Step 6: Excess fluid recovery. Control unit 25 opens pipeline control valve 10 on positive pressure line 7 and air compressor 18 to restore positive pressure in sample injection chamber 3, and simultaneously opens pipeline control valve 10 on liquid inlet pipe 4; under positive pressure, excess fluid remaining in sample injection chamber 3 is discharged back to target sampling pool 2 through liquid inlet pipe 4, realizing fluid recovery and avoiding waste and secondary pollution; after the excess fluid is discharged (pressure sensor 15 detects that the pressure in sample injection chamber is stable and there is no significant pressure drop), close air compressor 18, positive pressure line 7 and pipeline control valve 10 on liquid inlet pipe 4.

[0040] Step 7: Cleaning of pipelines and sample inlet chamber 3. Control unit 25 opens pipeline control valve 10 on tap water pipeline 23, and tap water is delivered to cleaning nozzle 9 through tap water pipeline 23; after rinsing, the pipeline control valve 10 of the corresponding pipeline is closed, and the pipeline control valve 10 on positive pressure pipeline 7 and liquid inlet pipe 4 is opened again to discharge the cleaned waste liquid back to target sampling pool 2 or to be directed to waste liquid treatment system.

[0041] Step 8: Residual waste liquid removal. Control unit 25 closes the pipeline control valve 10 on inlet pipe 4 and positive pressure line 7, and opens the pipeline control valve 10 on negative pressure line 8 and vacuum pump 19 to establish negative pressure in sample injection chamber 3; under negative pressure, a small amount of residual cleaning waste liquid in drain pipe 5 is sucked into sample injection chamber 3; then, the pipeline control valve 10 on negative pressure line 8 is closed, and the pipeline control valve 10 on positive pressure line 7 and inlet pipe 4 is opened to discharge the residual waste liquid sucked into sample injection chamber 3; after discharge, all pipeline control valves 10 are closed, the system returns to its initial state, and waits for the next sampling command.

[0042] When multi-point synchronous sampling is required, in step S1, the pipeline control valves 10 of each negative pressure pipeline 8 in several sampling and retention units 1 are opened simultaneously, and subsequent steps are executed synchronously. It should be noted that the sampling method of the remote distributed sampling and retention system based on this embodiment can be adjusted and expanded according to actual usage requirements: In terms of adjustment, the target negative pressure value of step 1 and the target positive pressure value of step 4 can be adjusted according to the fluid viscosity difference, or the atmospheric pressure balancing step of step 3 can be omitted to directly perform positive pressure drainage (suitable for low viscosity fluids), and step 8 can be repeated before the cleaning work in step 7 to first suck the residual waste liquid in the drain pipe 5 into the sample chamber 3; In terms of expansion, a sample marking step can be added after the sample retention in step 5 (such as the drive mechanism linked to the coding device to mark the sampling time and location), and a positive pressure purging step can be added after step 7 or step 8, the air pressure regulating component can be activated to make the sample chamber 3 reach a positive pressure state and continuously use positive pressure airflow to purge the inlet pipe 4, drain pipe 5 and sample chamber 3 to remove the residual fluid attached to the pipes; after purging, the air pressure regulating component can be activated to restore the sample chamber 3 to an atmospheric pressure state to prepare for the next sampling.

[0043] In addition, in this embodiment, a conical funnel 1201 can be selectively fixedly installed on one side of the sample container 12, and a waste sample tank 30 is set below the conical funnel 1201. In order to further improve the accuracy of sampling and testing, before formal sampling and testing, a portion of the target sampling fluid can be drawn into the sample inlet chamber 3 and discharged into the waste sample tank 30 through the conical funnel 1201, thereby flushing the sample inlet chamber 3 and any remaining sample fluid from the previous batch in the pipeline.

[0044] Example 2: Compared to Example 1, this example provides a simpler and more economical system configuration: First, it omits the cleaning components, positive pressure pipelines, and related air sources; the system relies solely on switching between negative and normal pressure and utilizes gravity for fluid discharge and recovery. Second, a waste sample container is installed below the drain pipe to discharge pipeline residues before formal sampling, further enhancing the ability to prevent cross-contamination. Other parts not mentioned are the same as or similar to those in Example 1 and will not be described further here.

[0045] like Figure 4 As shown, the remote distributed sampling and retention system of this embodiment has the same basic framework as that of Embodiment 1. The following focuses on describing the differences between it and Embodiment 1.

[0046] Target sampling pool connection method: The inlet pipe 4 of each sampling and retention unit 1 is connected to the target sampling pool 2. By controlling the opening and closing of the corresponding valves, time-sharing sampling of the points under the responsibility of the unit can be achieved.

[0047] Pressure regulating assembly: The pressure regulating assembly in this embodiment only includes an atmospheric pressure pipeline 6 and a negative pressure pipeline 8, and does not have a positive pressure pipeline. Its connection method is similar to that of Embodiment 1. The atmospheric pressure pipeline 6 is connected to the atmosphere, and the negative pressure pipeline 8 is connected to the negative pressure gas tank 20. Both are connected to the sample injection chamber 3 through different gas pipes. By controlling the pipeline control valves 10 on these two pipelines, the sample injection chamber 3 can be switched between two states: negative pressure (sampling and aspiration) and atmospheric pressure (pressure relief, gravity drainage).

[0048] Waste sample container and its connections: such as Figure 4 As shown, a conical funnel 1201 is installed below the sampling output end 501 of the drain pipe 5, and the conical funnel 1201 is fixedly installed on one side of the sample retention container 12. A waste sample container 30 is installed below the conical funnel 1201 to receive the waste liquid used for cleaning before formal sampling.

[0049] Sampling method flow (specific steps corresponding to the system in this embodiment): The sampling method of this embodiment is automated and controlled by the control unit 25, and mainly includes the following steps: Step A (Preparation): According to the sampling plan, the control unit 25 opens the pipeline control valve 10 on the inlet pipe 4 of the target sampling pool 2.

[0050] Step B (Negative Pressure Suction): Same as steps 1 and 2 in Example 1. Close the valve of the atmospheric pressure line 6, open the valve of the negative pressure line 8 and the negative pressure source to generate negative pressure in the sample injection chamber 3, and quantitatively suck the fluid from the target sampling pool A into the sample injection chamber 3.

[0051] Step C (Relieve pressure to atmospheric pressure): Same as step 3 in Example 1. Close the negative pressure line 8 and open the atmospheric pressure line 6 to restore the sample injection chamber 3 to atmospheric pressure.

[0052] Step D (Waste Discharge and Contamination Prevention): Open the main pipeline control valve 10 connected to the drain pipe 5. Under normal pressure and gravity, any residual fluid that may be present in the sample injection chamber 3 from the previous sampling will be discharged into the waste sample tank 30 through the conical funnel 1201, thereby ensuring the purity of subsequent samples. After waste discharge is completed, close the main pipeline control valve 10 of the drain pipe 5.

[0053] Step E (Formal Sampling and Retention): Repeat steps B and C, again drawing in the fresh fluid to be retained into the sample inlet chamber 3 under negative pressure, and then depressurizing it to atmospheric pressure. Then, open the main pipeline control valve 10 of the drain pipe 5. Under the action of gravity, the fresh fluid in the sample inlet chamber 3 flows through the drain pipe 5 to the sampling output end 501, and then flows into the retention container 12, completing the retention.

[0054] Step F (Excess Fluid Recovery): After the sample retention is completed, open the pipeline control valve 10 of the inlet pipe 4. Under the action of gravity, the remaining excess fluid in the sample injection chamber 3 can flow back to the original target sampling pool A through the inlet pipe 4.

[0055] The two embodiments described above respectively cover two core combinations: "positive pressure + cleaning component + waste sample container" and "waste sample container + no positive pressure and no cleaning component". Based on the technical features defined in the claims of this invention, each technical feature is independent and compatible (without mutually exclusive technical conflicts). In addition to the two combinations described above, various other reasonable combinations can be formed, all of which fall within the protection scope of this invention. Moreover, their implementation principles and operating logic can be derived from the two embodiments described above, and can be implemented without adding new complete embodiments. The specific combination methods and descriptions are as follows: Combination 1: Equipped with positive pressure regulation, waste sample container 30, but without cleaning components. The following components are retained from Example 1: positive pressure pipeline 7 (for rapid drainage and positive pressure purging under positive pressure), sample retention assembly driven by a planar two-dimensional linear motion module, first level gauge 13, pressure sensor 15, and air compressor + vacuum pump supply method. A return pipe 32 and waste sample container 30 from Example 2 are added, and the cleaning assembly is removed. The implementation principle is as follows: drainage efficiency is improved through positive pressure regulation, and residual samples from previous sampling are removed through the waste sample container 30, eliminating the need for a cleaning assembly (suitable for scenarios with low fluid viscosity, low residue, and low cleaning requirements). The sampling method integrates rapid positive pressure drainage, positive pressure purging, and pre-drainage of waste samples, and can be directly adapted to the operation procedures of Examples 1 and 2 without requiring additional design of new operation steps.

[0056] Combination 2: Equipped with cleaning components and a waste sample container (30), but without positive pressure regulation. The cleaning components and first level gauge 13 from Example 1 are retained, as are the waste sample tank 30, basic air pressure regulation (atmospheric pressure + negative pressure), and vacuum pump air supply method from Example 2. The positive pressure pipeline 7 is removed. The implementation principle is as follows: the cleaning components remove residue from the inner wall of the sample inlet chamber, and the waste sample tank 30 removes pipeline residue. A basic air pressure regulation of negative pressure + atmospheric pressure is used (suitable for scenarios where drainage efficiency requirements are not high and cost is sensitive). The sampling method is as described in claims 12, 15, and 16, integrating the pre-drainage waste sample and cleaning steps. Gravity is used to achieve drainage and residual liquid removal. Its operation logic is consistent with Example 2, only adding a cleaning step (refer to the operation method of the cleaning components in Example 1).

[0057] Combination 3: Equipped with positive pressure regulation, cleaning components, and a waste sample tank (30), but without a second level gauge (14). The system retains the positive pressure pipeline 7, cleaning assembly, sample retention assembly driven by a planar two-dimensional linear motion module, first level gauge 13, pressure sensor 15, and air compressor + vacuum pump supply method from Example 1. It adds a return pipe + waste sample container 30 from Example 2 and removes the second level gauge 14. The implementation principle is as follows: It integrates the triple pollution control measures of positive pressure, cleaning, and waste sample container 30. The sampling volume is controlled by the first level gauge 13, and the second level gauge 14 is removed (suitable for scenarios with stable sampling environments and no need for overflow alarms). The sampling method integrates pre-discharge of waste samples, positive pressure sample retention, cleaning, and positive pressure purging steps. The operation process can be directly integrated based on the steps of Examples 1 and 2 without additional optimization.

[0058] Combination 4: Equipped with positive pressure regulation, a second level gauge 14, and a pressure sensor 15, but without cleaning components or a waste sample tank 30. The positive pressure pipeline 7, the sample retention component driven by the planar two-dimensional linear motion module, the first liquid level gauge 13, the second liquid level gauge 14, the pressure sensor 15, and the air supply method of air compressor + vacuum pump are retained from Example 1, while the cleaning component and waste sample tank 30 are removed. Its implementation principle is as follows: pipeline residue is removed by positive pressure purging, and the sampling volume is controlled and overflow alarm is achieved through the first and second liquid level gauges. The cleaning component and waste sample tank 30 are not required (suitable for clean fluid sampling in scenarios with no risk of residual contamination). The sampling method only retains the steps of negative pressure pumping, positive pressure sample retention, positive pressure discharge of residual liquid, and positive pressure purging. The operation process is simplified from Example 1 and can be directly implemented.

[0059] Combination 5: Includes waste sample container 30, second level gauge 14, and drive mechanism; lacks positive pressure regulation and cleaning components. The waste sample container 30, basic air pressure regulation (atmospheric pressure + negative pressure), vacuum pump air supply method, and pressure sensor 15 from Example 2 are retained. A sample retention component driven by a planar two-dimensional linear motion module and a second liquid level gauge 14 from Example 1 are added. The positive pressure pipeline 7 and cleaning component are removed. Its implementation principle is as follows: residue is removed through the waste sample container 30; fully automatic sample retention switching is achieved through the drive mechanism; and overflow alarm is triggered by the second liquid level gauge 14. It is suitable for scenarios with high automation requirements, cost sensitivity, and no need for positive pressure or cleaning. The sampling operation logic is consistent with Example 2.

[0060] It should be noted that the above combinations are merely illustrative examples and not exhaustive. Based on the technical features defined in the claims of this invention, all combinations of non-exclusive dependent technical features are within the scope of protection of this invention. The core implementation principles, structural connections, and sampling procedures of all combinations can be derived from the technical content of the above two embodiments. The selection of components and parameter settings (such as the number of sample containers, guide rail specifications, level gauge height, and air pressure range) can be adjusted according to actual needs without the need to add a new complete embodiment.

[0061] Further explanation: the compatibility of each technical feature is based on the following: the positive pressure pipeline 7 and the waste sample container 30 have no technical conflict and can both be used in conjunction with the basic air pressure regulation; the cleaning component can be independently installed in the sample inlet chamber without affecting the operation of other components such as air pressure regulation, waste sample container 30, and level gauge; the drive mechanism of the sample retention component can be selected according to automation requirements and has no association or conflict with features such as positive pressure, cleaning, and waste sample container 30; the level gauge, pressure sensor 15, and air supply method are all auxiliary functional components and can be independently added to any combination without changing the core sampling logic. Therefore, all feature combinations based on the claims are feasible.

[0062] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A remote distributed sampling and retention system, characterized in that, It includes several sampling and retention units (1), each of which is an independent sampling fluid loop structure. The sampling end of each sampling and retention unit (1) is connected to a different target sampling pool (2) of the sampled fluid. Each sampling and retention unit (1) includes: Sample inlet chamber (3) is used to temporarily store the sampled fluid; The liquid inlet pipe (4) is connected at one end to the sample inlet chamber (3) and at least one target sampling pool (2) at the other end; The drain pipe (5) has a sampling input end connected to the sample inlet chamber (3) at one end and a sampling output end (501) at the other end. The air pressure regulating component is connected to the sample injection chamber (3) to form a negative pressure or normal pressure state in the sample injection chamber (3) and realize the switching of at least two states. The negative pressure state is used to extract the sampled fluid or to extract the residual fluid in the drain pipe (5) after sampling. The normal pressure state is used to release pressure after the negative pressure state is applied. A sample retention assembly is located below the sampling output end (501) of the drain pipe (5) for collecting the sampled fluid; and pipeline control valves (10) are respectively installed on the inlet pipe (4), the drain pipe (5) and the pressure regulating assembly.

2. The remote distributed sampling and retention system according to claim 1, characterized in that, The pressure regulating component includes an atmospheric pressure pipeline (6) and a negative pressure pipeline (8). The atmospheric pressure pipeline (6) is connected to the atmosphere, and the negative pressure pipeline (8) is connected to a negative pressure gas source. The atmospheric pressure pipeline (6) and the negative pressure pipeline (8) are connected in parallel and then connected to the sample injection chamber (3) through the same gas pipe (11), or the atmospheric pressure pipeline (6) and the negative pressure pipeline (8) are connected to the sample injection chamber (3) through different gas pipes.

3. The remote distributed sampling and retention system according to claim 1, characterized in that, The pressure regulating component also includes a positive pressure pipeline (7) for creating a positive pressure state in the sample inlet chamber (3). The positive pressure state is used to output the sampled fluid to the sampling output end (501) of the drain pipe (5) or to return excess sampled fluid to the target sampling pool (2). The positive pressure pipeline (7) is connected to a high-pressure gas source.

4. The remote distributed sampling and retention system according to claim 1, characterized in that, Each of the sampling and retention units (1) also includes a cleaning component disposed in the sample inlet chamber (3) for cleaning the interior of the sample inlet chamber (3).

5. The remote distributed sampling and retention system according to claim 1, characterized in that, Below the sampling output end (501) of the drain pipe (5), there is a waste sample tank (30) for collecting waste liquid.

6. The remote distributed sampling and retention system according to claim 1, characterized in that, The sample retention assembly includes a plurality of sample retention containers (12) disposed below the sampling output end (501), and a driving mechanism for driving the sampling output end (501) or sample retention containers (12) of the drain pipe (5) to move so as to realize the flow of fluid to different sample retention containers (12).

7. The remote distributed sampling and retention system according to claim 6, characterized in that, The driving mechanism is a planar two-dimensional linear motion module, including two guide rails (16) orthogonally arranged on a horizontal plane, and a driving component (17) that slides with the two guide rails (16). The driving component (17) is fixedly connected to the sampling output end (501) of the drain pipe (5).

8. The remote distributed sampling and retention system according to claim 1, characterized in that, The inner wall of the sample inlet chamber (3) is provided with a first liquid level gauge (13), the height of which matches the rated fluid capacity required for one sampling.

9. The remote distributed sampling and retention system according to claim 8, characterized in that, The inner wall of the sample injection chamber (3) is provided with a second level gauge (14) which is higher than the first level gauge (13) in the height direction. The second level gauge (14) is used to trigger a fault alarm when the volume of the temporarily stored sampled fluid reaches the height of the second level gauge (14).

10. The remote distributed sampling and retention system according to claim 1, characterized in that, A pressure sensor (15) for monitoring the air pressure inside the sample inlet chamber (3) or on the pipeline of the air pressure regulating assembly is provided.

11. A sampling method using the remote distributed sampling and retention system as described in claim 1 or 3, characterized in that, The sampling method includes: Step 1: Activate the air pressure regulating component to bring the sample injection chamber (3) to a negative pressure state; Step 2: Open the inlet pipe (4) and temporarily store the collected fluid in the sample injection chamber (3); Step 3: Activate the air pressure regulating component to bring the sample injection chamber (3) to atmospheric pressure. Step 4: Open the drain pipe (5) to distribute the fluid to the sample retention component to complete the sample retention; Step 5: Open the inlet pipe (4) and drain the excess fluid back to the target sampling cell (2).

12. The sampling method according to claim 11, characterized in that, Using the pressure regulating assembly as described in claim 3, in steps 4 and 5, a positive pressure is created inside the sample injection chamber (3) to facilitate the rapid discharge of fluid.

13. The sampling method according to claim 11, characterized in that, Using the pressure regulating component as described in claim 3, a positive pressure purging step is further included after step 5: the pressure regulating component is activated to bring the sample injection chamber (3) to a positive pressure state and the positive pressure airflow is continuously used to purge the liquid inlet pipe (4), the liquid outlet pipe (5) and the sample injection chamber (3) to remove the residual fluid attached to the pipes; after the purging is completed, the pressure regulating component is activated to restore the sample injection chamber (3) to a normal pressure state to prepare for the next sampling.

14. The sampling method according to claim 11, characterized in that, Using the cleaning assembly as described in claim 4, cleaning is performed after step 5 is completed, and after cleaning is completed, the inlet pipe (4) is opened to discharge the cleaned fluid.

15. The sampling method according to claim 11, characterized in that, Using the waste sample container (30) as described in claim 5, after step 3 is completed, the fluid in the sample inlet chamber (3) is discharged into the waste sample container (30) by gravity or positive pressure to avoid the residual fluid from the previous sampling cycle from affecting the sampling results of this time. After completing this step, steps 1 to 3 are repeated to collect the fluid to be retained in this time.

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