A pressure and liquid flow rate control device for a positive pressure solid phase extraction instrument and methods of use thereof

Abstract

The present application belongs to the technical field of testing devices, and particularly relates to a positive pressure solid phase extraction instrument gas pressure and liquid flow rate control device and a use method thereof. The device comprises a plurality of extraction columns, a measuring cylinder is arranged directly below the lower end outlet of each extraction column, and a multi-point laser sensor is arranged on the side surface of the measuring cylinder and the lower end outlet of the extraction column. An adsorbent filler sieve plate is arranged at the bottom of each extraction column, a sample liquid B is arranged above the adsorbent filler sieve plate, and a pressure air or inert gas is arranged between the liquid surface of the sample liquid B and the lower surface of a cover. The cover is screwed on the upper opening of the extraction column, a pressure sensor is arranged on the cover, a gas slip ring is arranged at the center of the cover, a gas hose is connected to the gas inlet of the gas slip ring, the other end of the gas hose is connected to an electric pressure regulating valve, and the gas inlet end of the electric pressure regulating valve is connected to a gas source. The device solves the problem of liquid flow rate control at the outlet of the extraction column, prevents the explosion of the individual extraction column caused by blockage, and improves the detection quality and efficiency.

Description

Technical Field

[0001] This invention belongs to the field of testing equipment technology, and specifically relates to a gas pressure and liquid flow rate control device for a positive pressure solid phase extraction instrument and its usage method. Background Technology

[0002] Solid-phase extraction (SPE) is a sample pretreatment step in the testing process. It utilizes a solid adsorbent to adsorb the target compound from the sample matrix and interfering compounds in a liquid sample, followed by elution with an eluent or desorption by heating, achieving the separation and enrichment of the target compound. SPE devices are classified as positive-pressure and negative-pressure. Positive-pressure SPE devices use air as a power source to pass through the solid-phase extraction column, while negative-pressure SPE devices use vacuum as a power source to pass through the solid-phase extraction column. The solid-phase extraction column is often a syringe-type polypropylene tube, with adsorbent packing and a sieve plate in the lower part of the column. The upper end of the solid-phase extraction column is open, and the liquid exits from the lower outlet of the extraction column through the adsorbent packing and sieve plate. Positive pressure solid-phase extraction (PSPE) involves vertically inserting a plunger into the extraction column and using positive air pressure to force the sample liquid through the adsorbent sieve and out through the lower outlet of the extraction column. Alternatively, the upper end of the extraction column can be sealed with a cap, and pressurized air or inert gas can be introduced to force the sample liquid through the adsorbent sieve and out through the lower outlet of the extraction column. The outflow velocity of the liquid is strictly controlled; if the flow rate does not meet the requirements, impurities will not be thoroughly filtered, affecting the determination of the target analyte content. Although the extractor can be set to adjust the pressure of the air or inert gas entering the sealed cap, it cannot guarantee the outlet liquid flow rate. This is because the reaction of each individual sample liquid through the adsorbent packing sieve is different, while the gas pressure entering the extraction column cavity is basically the same. This results in varying droplet flow rates at the lower outlet of some extraction columns, making it impossible to effectively control the outlet liquid flow rate of each extraction column. Sometimes, blockages can occur in individual extraction columns as the sample liquid passes through the adsorbent packing sieve, leading to excessive pressure in the extraction column cavity and cap rupture, resulting in an unsafe situation. All of these factors contribute to a decrease in detection quality and efficiency.

[0003] Purpose of the invention

[0004] To overcome the shortcomings of existing technologies, a pressure and liquid flow rate control device for a positive pressure solid phase extraction instrument and its usage method are provided. This device controls the flow rate of liquid at the outlet of each extraction column and prevents the cap from bursting in the event of a "blockage", thereby improving detection quality and efficiency. Summary of the Invention

[0005] This invention is achieved through the following technical solution:

[0006] A pressure and liquid flow rate control device for a positive pressure solid phase extractor includes several extraction columns, a measuring cylinder is provided directly below the lower end outlet of each extraction column, and a multi-point laser sensor is provided on the common side of the measuring cylinder and the lower end outlet of the extraction column.

[0007] An adsorbent packing sieve plate is placed at the bottom of the single extraction column. The sample liquid B is above the adsorbent packing sieve plate. The liquid level of the sample liquid B to the lower surface of the cap is pressurized air or inert gas. The cap is screwed onto the upper opening of the extraction column. A pressure sensor is installed on the cap. An air slip ring is installed in the center of the cap. The air inlet of the air slip ring is connected to a gas hose. The other end of the gas hose is connected to an electric pressure regulating valve. The air inlet of the electric pressure regulating valve is connected to a gas source.

[0008] Based on the above scheme, preferably, several extraction columns are vertically placed in holes provided in the upper plate and lower plate of the support, wherein the holes in the upper plate of the support are radially positioned at the upper part of the extraction column, and the holes in the lower plate of the support are radially and axially positioned at the lower part of the extraction column.

[0009] Based on the above scheme, the preferred embodiment is that the electrical control wires of the multi-point laser sensor, pressure sensor, and electric pressure regulating valve are all connected to the display PLC controller via wired or wireless connection.

[0010] The method of using the gas pressure and liquid flow rate control device of the positive pressure solid phase extraction instrument includes the following steps:

[0011] S1. Place the adsorbent packing sieve plate into each extraction column, inject the sample liquid B, and tighten the cap. Vertically insert it into the holes set in the upper and lower plates of the support. Press the working button in the display PLC controller, and each electrical control component will enter the working state.

[0012] S2, the PLC controller controls the electric pressure regulating valve to slowly open to the programmed setting range, and each multi-point laser sensor sends the image data of the droplet falling speed and the liquid level of liquid A in the measuring cylinder and the position of the measuring scale line to the PLC controller in real time.

[0013] S3. When the PLC controller determines, based on the programming, that the image and monitoring data of the droplets falling from the lower end of an extraction column are about to exceed the programmed upper limit, the PLC controller controls the electric pressure regulating valve connected to the extraction column to appropriately reduce the pressure and supply gas.

[0014] S4. When the PLC controller determines, based on the programming, that the image and monitoring data of the droplets falling from the lower end of an extraction column are about to fall below the programmed lower limit, the PLC controller controls the electric pressure regulating valve connected to that extraction column to appropriately increase the gas supply; through steps S3 and S4, the flow rate of the droplets at the lower end of each extraction column is controlled to always conform to the programming setting;

[0015] S5. When the PLC controller determines, based on the programming, that the image and monitoring data of the droplet falling from the lower end of an extraction column are about to fall below the programmed lower limit, the PLC controller controls the electric pressure regulating valve connected to the extraction column to appropriately increase the gas supply. However, if the image and monitoring data of the droplet falling from the lower end of the extraction column do not improve significantly, and the pressure value of the pressure sensor on the extraction column cap is about to reach the specified limit, the PLC controller controls the electric pressure regulating valve connected to the extraction column to stop supplying gas. This indicates that a blockage has occurred between the sample liquid B and the adsorbent packing sieve plate 8 in the extraction column.

[0016] Beneficial technical effects of the present invention:

[0017] This invention replaces the original extractor, which simultaneously delivers the same pressure gas to all extraction columns and whose individual extraction column pressure cannot be individually adjusted, with the gas pressure in each individual extraction column now allowing for individual control. Furthermore, the original extractor cannot effectively control the outlet liquid flow rate; this invention enables quantitative control of the outlet flow rate (volume flow) and eliminates the possibility of extraction column cap bursting.

[0018] The positive pressure solid phase extraction instrument described in this invention has a gas pressure and liquid flow rate control device that solves the problem of liquid flow rate control at the extraction column outlet and also prevents individual extraction columns from becoming blocked and bursting, thereby improving detection quality and efficiency. Attached Figure Description

[0019] The structural features and usage of the present invention will be further described with reference to the accompanying drawings:

[0020] Figure 1 This is a main sectional view of the present invention;

[0021] Figure 2 It is a control principle diagram;

[0022] In the diagram: 1. Multi-point laser sensor, 2. Liquid A, 3. Measuring cylinder, 4. Workbench surface, 5. Display PLC controller, 6. Adsorbent packing sieve plate, 7. Sample liquid B, 8. Extraction column, 9. Cap, 10. Air slip ring, 11. Air hose, 12. Electric pressure regulating valve, 13. Pressure sensor, 14. Upper plate of the support, 15. Lower plate of the support. Detailed Implementation

[0023] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0024] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, unless otherwise expressly indicated by the invention, the singular form is also intended to include the plural form. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0025] For ease of description, the words "up," "down," "left," and "right" appearing in this invention only indicate that they are consistent with the up, down, left, and right directions of the accompanying drawings themselves, and do not limit the structure. They are merely for the purpose of facilitating the description of this invention and simplifying the description, and do not indicate or imply that the device or component 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 invention.

[0026] Terminology Explanation: The terms "installation," "connection," "linking," and "fixing" in this invention should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction relationship between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0027] Figure 1-2 This is one of the embodiments of the present invention.

[0028] A pressure and liquid flow rate control device for a positive pressure solid phase extractor mainly consists of: an electric pressure regulating valve 12, a pressure sensor 13, a multi-point laser sensor 1, and a display PLC controller 5.

[0029] In this embodiment, multiple extraction columns 8 are vertically placed within holes in the upper plate 14 and lower plate 15 of the support. The holes in the upper plate 14 provide radial positioning for the upper part of the extraction columns 8, while the holes in the lower plate 15 provide radial and axial positioning for the lower part of the extraction columns 8. A measuring cylinder 3 is positioned directly below the lower outlet of the extraction columns 8. The measuring cylinder 3 is horizontally placed on the worktable surface 4 and has measuring scale lines. A multi-point laser sensor 1 is located on the common side of the measuring cylinder 3 and the outlet. The multi-point laser sensor 1 is placed on the worktable surface 4 via a tripod. The function of the multi-point laser sensor 1 is to confirm the position of the target object using a high-definition camera and to acquire multi-point change information using laser tracking. That is, to monitor the changes in the droplet falling speed and the position of the liquid level A2 in the measuring cylinder 3 relative to the measuring scale lines. An adsorbent packing sieve plate 6 is placed at the bottom of the extraction column 8. The sample liquid B7 is placed above the adsorbent packing sieve plate 6. The liquid level of the sample liquid B7 to the lower surface of the cap 9 is filled with pressurized air or inert gas. The cap 9 is screwed onto the upper opening of the extraction column 8. A pressure sensor 13 is installed on the cap 9. An air slip ring 10 is installed in the center of the cap 9. The air inlet of the air slip ring 10 is connected to a gas hose 11. The other end of the gas hose 11 is connected to an electric pressure regulating valve 12. The air inlet of the electric pressure regulating valve 12 is connected to a gas source.

[0030] The electrical control wires of each multi-point laser sensor 1, pressure sensor 13, and electric pressure regulating valve 12 are connected to the display PLC controller 5 via wired or wireless connection. The control program, image analysis, and self-learning adaptive program are input into the PLC controller. For example, the adjustment range of the electric pressure regulating valve 12 corresponding to the normal droplet falling frequency range is set, and the electric pressure regulating valve 12 stops supplying gas to the extraction column 8 when the pressure sensor 13 reaches the specified upper limit value.

[0031] Instructions for use: Place the adsorbent packing sieve plate 6 into each extraction column 8, inject the sample liquid B7, and tighten the cap 9. Insert the column vertically into the holes provided on the upper plate 14 and lower plate 15 of the support. Press the working button on the PLC controller 5, and all electrical control components will enter the working state. The PLC controller controls the electric pressure regulating valve 12 to slowly open to the programmed setting range. Each multi-point laser sensor 1 sends real-time image data of the droplet falling speed and the liquid level and measurement scale position in the measuring cylinder 3 to the PLC controller. When the PLC controller determines, based on the programming, that the image and monitoring data of the droplet falling at the lower end of an extraction column 8 are about to exceed the programmed upper limit, the PLC controller controls the electric pressure regulating valve 12 connected to that extraction column 8 to appropriately reduce the pressure and supply gas; conversely, it increases the pressure and supplies gas. This effectively controls the flow rate of the droplets at the lower end of each extraction column 8 to always conform to the programmed setting. When the PLC controller determines, based on its programming, that the image and monitoring data of the droplets falling from the lower end of extraction column 8 are about to fall below the programmed lower limit, the PLC controller controls the electric pressure regulating valve 12 connected to extraction column 8 to appropriately increase the gas supply. However, the image and monitoring data of the droplets falling from the lower end of extraction column 8 still show no significant improvement. When the pressure value of the pressure sensor 13 on the cap 9 of extraction column 8 is about to reach the specified limit, the PLC controller controls the electric pressure regulating valve 12 connected to extraction column 8 to stop the gas supply. This indicates that a blockage has occurred between the sample liquid B7 and the adsorbent packing sieve plate 6 inside extraction column 8 (see attached image). Figure 1 Since gas is no longer supplied to the extraction column 8, the possibility of the extraction column 8 cap bursting is avoided. The entire process of image measurement data of the droplets falling from the lower end of each extraction column 8 and the change of the liquid level of liquid A2 in the measuring cylinder 3 relative to the measuring scale line can be traced in the display PLC controller 5.

[0032] This device solves the problem of liquid flow rate control at the outlet of extraction column 8, and also prevents individual extraction columns 8 from becoming blocked and bursting, thus improving detection quality and efficiency.

[0033] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A positive pressure solid phase extraction instrument gas pressure and liquid flow rate control device, characterized in that: comprising several extraction columns (8), the lower end outlet of a single extraction column (8) is provided with a measuring cylinder (3) directly below, and a multi-point laser sensor (1) is arranged on the side of the measuring cylinder (3) and the lower end outlet of the extraction column (8); a single extraction column (8) is placed with an adsorbent filler sieve plate (6) at the bottom, and a sample liquid B (7) is arranged above the adsorbent filler sieve plate (6), the liquid surface of the sample liquid B (7) to the lower surface of a cover (9) is a pressure air or inert gas, the cover (9) is screwed on the upper opening of the extraction column (8), a pressure sensor (13) is arranged on the cover (9), a gas slip ring (10) is arranged at the center of the cover (9), a gas hose (11) is connected to the gas inlet of the gas slip ring (10), the other end of the gas hose (11) is connected to an electric pressure regulating valve (12), and the gas inlet end of the electric pressure regulating valve (12) is connected to a gas source; several extraction columns (8) are vertically placed in the holes arranged on the upper plate (14) and the lower plate (15) of the support, wherein the holes of the upper plate (14) of the support are radially positioned on the upper part of the extraction column (8), and the holes of the lower plate (15) of the support are radially and axially positioned on the lower part of the extraction column (8); the electric control wires of the multi-point laser sensor (1), the pressure sensor (13), and the electric pressure regulating valve (12) are connected to the display PLC controller (5) by wire or wirelessly; a control program, image analysis and self-learning adaptive program are input to the PLC controller (5), the adjustment range of the electric pressure regulating valve (12) corresponding to the normal liquid drop falling frequency range is set, and when the pressure sensor (13) reaches the specified upper limit value, the electric pressure regulating valve (12) no longer supplies gas to the extraction column (8). The method comprises the following steps: S1, placing the adsorbent filler sieve plate (6) in each extraction column (8), injecting the sample liquid B (7), and screwing the cover (9), vertically inserting into the holes arranged on the upper plate (14) and the lower plate (15) of the support, and pressing the working button in the display PLC controller (5), so that each electric control component enters the working state; S2, the PLC controller controls the electric pressure regulating valve (12) to slowly open to the programmed setting range, and each multi-point laser sensor (1) sends the image data of the liquid drop falling speed change and the liquid surface of the liquid A (2) in the measuring cylinder (3) to the PLC controller in real time; S3, when the PLC controller determines that the image and monitoring data of the liquid drop falling at the lower end outlet of the extraction column (8) will be higher than the programmed upper limit according to the programming, the PLC controller controls the electric pressure regulating valve (12) connected to the extraction column (8) to appropriately reduce the gas supply pressure; S4, when the PLC controller determines that the image and monitoring data of the liquid drop falling at the lower end outlet of the extraction column (8) will be lower than the programmed lower limit according to the programming, the PLC controller controls the electric pressure regulating valve (12) connected to the extraction column (8) to appropriately increase the gas supply pressure; through steps S3 and S4, the flow rate of the liquid drop at the lower end outlet of each extraction column (8) always meets the programmed setting.

2. The method of using a pressure and liquid flow rate control device for a positive pressure solid phase extraction instrument of claim 1, wherein: ​ ​ ​ ​ ​ S5, when the PLC controller determines that the image and monitoring data of the liquid droplet falling from the lower end outlet of the extraction column (8) is about to be lower than the programmed lower limit, the PLC controller controls the electric pressure regulating valve (12) connected to the extraction column (8) to appropriately increase the pressure of the gas supply, but the image and monitoring data of the liquid droplet falling from the lower end outlet of the extraction column (8) still do not improve significantly, and when the pressure value of the pressure sensor (13) on the cover (9) of the extraction column (8) reaches the specified limit, the PLC controller controls the electric pressure regulating valve (12) connected to the extraction column (8) to stop the gas supply, indicating that a blockage state has occurred between the sample liquid B (7) in the extraction column (8) and the adsorbent filler screen plate (6).

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