TWM674389U - Online pre-concentration sampling and injection device - Google Patents

Abstract

The present utility model provides an online pre-concentration sampling and injection device, comprising: an absorption bottle with double-layer structure, having a bubbling device and an injection tube inside; a multi-way flow control valve with multiple ports for controlling flow directions between multiple pipelines; an injection valve set at the detector end; a liquid transfer pump for extracting liquid from the absorption bottle; and a gas suction pump connected to the absorption bottle and the multi-way flow control valve. This online pre-concentration sampling and injection device adopts a rear-drawing design, which can reduce dead corners and residue possibilities during the sampling process, improve analysis repeatability, and can be integrated with various detectors to realize online analysis of compounds in various types of gases.

Description

Online pre-concentration sampling device

The present invention is an online pre-concentration sampling and injection device, in particular a device that can be used for collecting and analyzing gas and liquid samples.

In the existing technology, most of the same type of collection devices adopt a forward-push design. The forward-push design is to install a pressurized or pushed gas extraction pump on the sampling pipeline to push the sample into the system through mechanical force. This design requires more valves to control the pressurized and pushed samples, which increases the complexity of the system. At the same time, the internal structure of the gas extraction pump is prone to forming dead corners, and little attention is paid to avoiding dead corners. This design has the following problems: 1. The sample is affected by the mechanical pushing force, which may change the physical state of the sample. 2. The internal structure of the pump will form dead corners, resulting in sample residue. 3. The pump needs to be inspected and maintained regularly, and it is difficult to clean. 4. Cross-contamination is prone to occur.

Currently, most similar devices on the market use PTFE absorption bottles. However, different substances require different absorption bottle materials. For example, metal analysis requires PFA, strong acid analysis requires glass, strong bases/amines require PTFE, and weak acids and weak bases are suitable for glass. This limitation of a single material reduces the application range of the device.

Furthermore, few devices on the market can directly accommodate a wide range of components and detectors, and none utilize a single pipeline flow path design for online analysis of multiple components. Existing absorption bottles are mostly made of PTFE, which limits their applicability.

In light of the above, the purpose of this new device is to provide an online pre-concentration sampling and injection device. This device uses a back-introduction design to reduce dead spots and the possibility of residual gas during the sampling process, improve analytical repeatability, and can be integrated with a variety of detectors to enable online analysis of compounds in various gas types.

According to the present disclosure, an online pre-concentration sampling and injection device is provided, which includes: an absorption bottle with a double-layer structure for capturing and concentrating the components to be tested in the sample; a multi-way flow control valve with multiple interfaces for controlling the flow between multiple pipelines; an injection valve, arranged at a detector end and connected to the multi-way flow control valve and a flushing liquid pipeline; a liquid transfer pump, connected to the multi-way flow control valve, for extracting the liquid in the absorption bottle. a gas extraction pump connected to the absorption bottle and the multi-way flow control valve, for generating negative pressure to introduce the gas sample into the absorption bottle; wherein the multi-way flow control valve has ten interfaces, one of which is connected to the absorption bottle, and another interface is connected to the injection valve; the absorption bottle is connected to the gas extraction pump through a first pipeline and to the liquid transfer pump through a second pipeline; and the injection valve is connected to the flushing liquid pipeline.

In one embodiment, the device further includes: a constant temperature absorption liquid quantitative loop, which is a pipeline with a fixed volume, connected to the multi-way flow control valve, and is used to quantitatively control the amount of absorption liquid used; and an injection quantitative loop, which is a pipeline with a fixed volume, connected to the injection valve, and is used to quantitatively control the volume of the liquid to be tested entering the detector.

In one embodiment, the gas extraction pump includes a metering valve for controlling the flow rate to ensure a fixed sample volume.

In one embodiment, a foaming device and a sampling tube are provided inside the absorption bottle. The foaming device is used to increase the contact area between the gas sample and the absorption liquid to improve the capture efficiency. The sampling tube is used to introduce the captured components into a detector at the rear end.

In one embodiment, the multi-way flow control valve has multiple interfaces for introducing pure water into the absorption bottle through the multi-way flow control valve for connecting a nitrogen pipeline, a pure water pipeline and the injection tube. The pure water pipeline is used to introduce pure water into the absorption bottle through the multi-way flow control valve, and the nitrogen pipeline is used to introduce nitrogen into the absorption bottle through the multi-way flow control valve. One end of the injection tube is arranged in the absorption bottle, and the other end is connected to the multi-way flow control valve.

In one embodiment, the constant temperature absorption liquid quantitative loop and the injection quantitative loop are used for the injection of fixed volume samples. These quantitative loops are actually fixed volume pipelines. By switching the valve, the liquid remaining in the fixed volume pipeline is introduced into the required pipeline during the switching, thereby achieving the injection of fixed volume liquid.

The present invention also provides a sampling method for an online pre-concentration sampling and injection device, which includes the following steps: generating negative pressure in an absorption bottle through a gas extraction pump to introduce a gas sample into the absorption bottle; allowing the gas sample to fully contact the absorption liquid through a foaming device in the absorption bottle to capture the target substance in the sample; extracting the absorption liquid containing the sample through a liquid transfer pump; introducing the absorption liquid into a constant temperature absorption liquid quantitative loop by switching the multi-way flow control valve; controlling the sample volume entering the detector through the injection quantitative loop; and introducing the quantified sample into the detector 11 through the injection valve for analysis.

In one embodiment, before the gas sample is introduced into the absorption bottle, a preliminary step is included: a predetermined amount of pure water is introduced into the absorption bottle as an absorption liquid through the multi-way flow control valve; nitrogen is used to push the predetermined amount of pure water into the absorption bottle; and the analyte in the gas sample can be captured by the absorption liquid.

In one embodiment, after the sample analysis is completed, a cleaning step is included: pure water is introduced through the multi-way flow control valve to clean the absorption bottle and the pipeline; nitrogen is introduced through the multi-way flow control valve to flush the pipeline to remove residual substances and prepare for the next sampling.

In one embodiment, the absorption liquid can be selected according to the characteristics of the substance to be detected: when the substance to be detected is a metal, nitric acid is used as the absorption liquid; when the substance to be detected is an ionic or polar substance, pure water is used as the absorption liquid.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

The following description contains specific information about illustrative embodiments of the present invention. The drawings and accompanying detailed descriptions herein are directed only to these illustrative embodiments. However, the present invention is not limited to these illustrative embodiments. Those skilled in the art will recognize other variations and embodiments of the present invention. In addition, the drawings and illustrations herein are generally not drawn to scale and do not correspond to actual relative dimensions.

For the sake of consistency and ease of understanding, the same features are identified by reference numerals in the exemplary drawings. However, features in different embodiments may differ in other respects and should not be limited to the features shown in the drawings. For the sake of consistency and ease of understanding, the same features are identified by reference numerals in the exemplary drawings. However, features in different embodiments may differ in other respects and should not be limited to the features shown in the drawings.

The terms used in this disclosure are used only to describe specific embodiments and are not intended to limit the scope of this disclosure. Unless otherwise specified, the singular forms "a," "an," "the," and "the" are intended to include the plural forms. The terms "include," "including," or "having" as used herein specify the presence of a feature, region, integer, step, operation, element, and/or component, but do not preclude the presence or addition of other features, regions, integers, steps, operations, elements, components, and/or groups thereof.

The term "and/or" is understood to include any and all combinations of one or more of the related listed items. Although terms such as "first," "second," and "third" may appear in the present invention to describe different elements, components, regions, parts, and/or cross-sections, these elements, components, regions, parts, and/or cross-sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, part, and/or cross-section from another element, component, region, layer, or cross-section. Therefore, without departing from the teachings of the present invention, a first element, component, region, part, or cross-section described below may also be named a second element, component, region, layer, or cross-section.

Please refer to Figure 1, which is a schematic diagram of the composition of this new detection system. The online pre-concentration sampling and injection device 10 includes an absorption bottle 101, which has a double-layer structure for capturing and concentrating the components to be tested in the sample. The double-layer structure can provide thermal insulation function, reduce heat loss, and add a water-cooled low-temperature circulation method to cool and control the temperature when low-temperature absorption is required. Furthermore, the absorption bottle 101 of the present invention can be made of different materials according to the substance to be tested. For example, when the substance to be tested is metal, PFA material with good chemical stability is used; when the substance to be tested is a strong acid, glass material is used; when the substance to be tested is a strong base or amine, PTFE material is used; when the substance to be tested is a weak acid or weak base, glass material is used. The selection of different materials mainly considers properties such as corrosion resistance and dissolution resistance to ensure the accuracy of the analysis. In one embodiment, a foaming device 102 and a sampling tube 103 are provided inside the absorption bottle 101. The foaming device 102 is used to form bubbles in the water with the introduced gas sample, increasing the contact opportunity and area between the gas sample and the absorption liquid, thereby improving the absorption probability and capture efficiency of water-soluble or polar molecules. One end of the sampling tube 103 is set in the absorption bottle 101, and the other end is connected to a multi-way flow control valve 104, which is used to introduce the absorption liquid that has captured the air sample components into the pipeline of a detector 11 at the rear end. The present invention can be integrated with various detectors 11, such as ion chromatography (IC) for analyzing acid and base components and amines; liquid chromatography (LC) for analyzing industrial oxidants, fluorescent agents, and solvents; and inductively coupled plasma mass spectrometry (ICP-MS) for analyzing metal components. As long as the detector 11 has an injection valve, the absorbent to be tested can be introduced into the detector 11 for analysis via the present pipeline connection method.

In addition, the multi-way flow control valve 104 has several interfaces for controlling the flow direction between multiple pipelines and changing the connection relationship between these interfaces by switching positions. One interface is connected to the absorption bottle 101, and the other interface is connected to an injection valve 105; the interfaces of the multi-way flow control valve 104 are also used to connect a nitrogen pipeline and a pure water pipeline. The pure water pipeline is used to introduce pure water into the absorption bottle 101 as an absorption liquid through the multi-way flow control valve 104. The nitrogen pipeline is used to introduce nitrogen into the absorption bottle 101 through the multi-way flow control valve 104 to assist in pushing a quantitative amount of pure water into the absorption bottle 101, and is used to flush the pipeline to remove residual substances. The multi-way flow control valve 104 is a 10-port, two-way valve with two switching positions. In the first position, the nitrogen line is connected to the absorption bottle 101, and the pure water line is closed. In the second position, the pure water line is connected to the absorption bottle 101, and the nitrogen line is closed. This switching method allows for flexible control of the timing of the introduction of different fluids.

The online pre-concentration sampling and injection device 10 also includes a liquid transfer pump 106 and a gas extraction pump 107. The liquid transfer pump 106 is connected to the multi-way flow control valve 104 and is specifically used to extract liquid and drain water from the absorption bottle 101, while the gas extraction pump 107 is also connected to the multi-way flow control valve 104. In one embodiment, the gas extraction pump 107 includes a certain metering valve 1071. The metering valve 1071 is used to control the flow rate to ensure that the sampling volume is fixed and the sampling is accurate. The gas extraction pump 107 is used to generate negative pressure in the absorption bottle 101, so that the gas sample is introduced into the absorption bottle 101.

In one embodiment, the online pre-concentration sampling and injection device 10 includes a constant temperature absorption liquid quantitative loop 108 and a sampling quantitative loop 109. The constant temperature absorption liquid quantitative loop 108 and the sampling quantitative loop 109 are pipelines with fixed volumes. The constant temperature absorption liquid quantitative loop 108 is connected to the multi-way flow control valve 104 to quantitatively control the amount of absorption liquid used, ensuring that a fixed volume of absorption liquid is used each time. The sampling loop 109 is connected to the sampling valve 105 and is used to quantitatively control the volume of the test liquid entering the detector 11, ensuring that the same volume of sample is used for each analysis. Furthermore, the sampling valve 105 can be further positioned near the detector 11 and connected to a flushing liquid line 1051. This flushing liquid line 1051 is used to push the test liquid in the sampling loop 109 into the detector 11 for analysis. The constant temperature absorption liquid loop 108 and the sampling loop 109 are switched by valves, directing the liquid remaining in the fixed volume pipeline to the required pipeline during switching, achieving fixed volume liquid sampling.

As mentioned above, this new model utilizes a rear-stage gas pipeline design, placing the gas extraction pump at the rear end of the sampling flow path. This pump draws the sample into the absorption bottle. This design reduces the presence of residual gas and dead spots in the sampling pipeline caused by the gas extraction pump. With fewer valves and piping components, the repeatability of online sampling and analysis is improved. Furthermore, the absorption bottle utilizes a double-layered glass design, which not only provides insulation and reduces heat loss, but also allows for a water-cooled low-temperature circulation system for temperature control when low-temperature absorption is required, increasing the stability of the operating environment.

Please refer to Figure 2, which shows the operation steps of the novel sampling method. The novel online pre-concentration sampling method mainly includes the following steps: a sample introduction step 201: a negative pressure is generated in the absorption bottle 101 by the gas extraction pump 107 to introduce the gas sample into the absorption bottle 101. The use of this back-introduction design can reduce the problem of dead corners and residues; a sample capture step 202: the gas sample is fully contacted with the absorption liquid in the absorption bottle 101 through the foaming device 102, and the contact area is increased by foaming to improve the absorption of the substance to be tested. Capture efficiency; an absorption liquid extraction step 203: The absorption liquid containing the sample is extracted through the liquid transfer pump 106 and the absorption liquid that has captured the substance to be tested is discharged; a fixed amount control step 204: By switching the multi-way flow control valve 104, the absorption liquid is introduced into the constant temperature absorption liquid quantitative loop 108, and the injection quantitative loop 109 controls the volume of the sample entering the detector 11 to ensure that a fixed volume of sample is used for analysis; a sample analysis step 205: After the quantified sample is introduced through the injection valve 105, it is further analyzed in the detector 11.

Referring to FIG. 3 , in one embodiment, the following preparatory steps are performed before the sample introduction step 201 : an absorption liquid preparation step 301 : introducing a predetermined amount of pure water into the absorption bottle 101 via the multi-way flow control valve 104 to serve as the absorption liquid for capturing the analyte; and an auxiliary pushing step 302 : using nitrogen to push a predetermined amount of pure water to ensure that the pure water enters the absorption bottle 101 so that the analyte in the gas sample can be captured by the absorption liquid.

Referring to FIG. 4 , in one embodiment, after the sample analysis step 205 is completed, the following steps are performed: a pure water cleaning step 2051 : pure water is introduced through the multi-way flow control valve 104 to clean the absorption bottle 101 and the piping system; a nitrogen flushing step 2052 : nitrogen is introduced through the multi-way flow control valve 104 to flush and remove residual substances in the piping in preparation for the next sampling.

In one embodiment, different absorption liquids can be selected based on the characteristics of the substance to be measured. For example, if metal composition analysis is performed, nitric acid is used as the absorption liquid, which is suitable for capturing metal substances in the gas; if ionic or polar substance analysis is performed, pure water is used as the absorption liquid, which is suitable for capturing water-soluble or highly polar substances.

In summary, the novel method features a back-introduction design that uses negative pressure to guide the sample, effectively reducing dead spots and carryover issues, thereby improving analytical accuracy and reproducibility. Furthermore, the design of the quantitative loop ensures precise control of sample volume. Combined with the choice of different absorbents, this method is applicable to the analysis of a wide range of analytes.

While the embodiments of the present invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments and encompasses design modifications that do not deviate from the spirit of the present invention. Furthermore, the present invention is susceptible to various modifications within the scope of the patent application, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also encompassed by the technical scope of the present invention. Furthermore, configurations obtained by interchanging elements described in the above embodiments that achieve the same effects are also encompassed.

10: On-line Pre-concentration Sampling and Injection Device 101: Absorption Bottle 102: Foaming Device 103: Injection Tube 104: Multi-Directional Flow Control Valve 105: Injection Valve 1051: Flushing Liquid Pipeline 106: Liquid Transfer Pump 107: Gas Extraction Pump 1071: Dosing Valve 108: Constant Temperature Absorption Liquid Loop 109: Injection Loop 11: Detector 201: Sample Introduction Step 202: Sample Capture Step 203: Absorption Liquid Extraction Step 204: Quantitative Control Step 205: Sample Analysis Step 2051: Pure Water Rinse Step 2052: Nitrogen Flushing Step 301: Absorption Liquid Preparation Step 302: Auxiliary Pushing Step

Figure 1 is a schematic diagram of the novel detection system. Figure 2 is a schematic diagram of the sample introduction method. Figure 3 is a schematic diagram of the preparatory steps before the sample introduction step. Figure 4 is a schematic diagram of the steps required after the sample analysis step.

10: Online pre-concentration sampling device

101: Absorption bottle

102: Foaming device

103: Sample injection tube

104: Multi-way flow control valve

105: Inlet valve

1051: Flushing liquid pipeline

106: Liquid transfer pump

107: Gas extraction pump

1071: Dosing Valve

108: Constant temperature absorption liquid quantitative ring

109: Injection loop

11: Detector

Claims (6)

An on-line pre-concentration sampling and injection device comprises: an absorption bottle with a double-layer structure for capturing and concentrating the components to be tested in the sample; a multi-way flow control valve with multiple interfaces for controlling the flow direction between multiple pipelines; an injection valve provided at a detector end and connected to the multi-way flow control valve and a flushing liquid pipeline; a liquid transfer pump connected to the multi-way flow control valve for extracting liquid from the absorption bottle. a gas extraction pump connected to the multi-way flow control valve, for generating negative pressure to introduce the gas sample into the absorption bottle; wherein the multi-way flow control valve has multiple interfaces, one of which is connected to the absorption bottle, and another interface is connected to the injection valve, the absorption bottle is connected to the gas extraction pump through a first pipeline, and is connected to the liquid transfer pump through a second pipeline, and the injection valve is connected to the flushing liquid pipeline. An online pre-concentration sampling and injection device as described in claim 1, wherein the device further includes: a constant temperature absorption liquid quantitative loop, which is a pipeline with a fixed volume, connected to the multi-way flow control valve, and is used to quantitatively control the amount of absorption liquid used; and an injection quantitative loop, which is a pipeline with a fixed volume, connected to the injection valve, and is used to quantitatively control the volume of the liquid to be tested entering the detector. An on-line pre-concentration sampling and injection device as described in claim 1, wherein the gas extraction pump includes a certain metering valve, which is used to control the flow rate to ensure that the sampling volume is fixed. As described in claim 1, the online pre-concentration sampling and injection device comprises a foaming device and an injection tube inside the absorption bottle, wherein the foaming device is used to increase the contact area between the gas sample and the absorption liquid to improve the capture efficiency, and the injection tube is used to introduce the captured components into a detector at the rear end. An online pre-concentration sampling and injection device as described in claim 4, wherein the multi-way flow control valve has multiple interfaces for introducing pure water into the absorption bottle through the multi-way flow control valve for connecting a nitrogen pipeline, a pure water pipeline and the injection tube, the pure water pipeline is used to introduce pure water into the absorption bottle through the multi-way flow control valve, the nitrogen pipeline is used to introduce nitrogen into the absorption bottle through the multi-way flow control valve, and one end of the injection tube is arranged in the absorption bottle, and the other end is connected to the multi-way flow control valve. As described in claim 2, the online pre-concentration sampling and injection device, wherein the constant temperature absorption liquid quantitative loop and the injection quantitative loop are used for injecting fixed volume samples. These quantitative loops are actually fixed volume pipelines. By switching the valve, the liquid remaining in the fixed volume pipeline is introduced into the required pipeline during the switching, thereby achieving the injection of fixed volume liquid.