WO2021238983A1

WO2021238983A1 - Thermal desorption sampling apparatus, thermal desorption device, and ion migration spectrometer detection device

Info

Publication number: WO2021238983A1
Application number: PCT/CN2021/096051
Authority: WO
Inventors: 张清军; 陈志强; 李元景; 李荐民; 刘耀红; 严李李; 李鸽; 曹彪; 朱伟平; 赵玉平
Original assignee: 同方威视技术股份有限公司; 清华大学
Priority date: 2020-05-29
Filing date: 2021-05-26
Publication date: 2021-12-02
Also published as: CN113804747A; CN113804747B; CN117074504A

Abstract

A thermal desorption sampling apparatus, a thermal desorption device, and an ion migration spectrometer detection device. The thermal desorption sampling apparatus comprises a holder (01) for holding a carrier (04) for an absorbed sample, and a desorption chamber (07) defining a closed desorption chamber (07) space for heating the carrier (04) for the absorbed sample within the desorption chamber (07) space, such that the sample is desorbed from the carrier (04), wherein the desorption chamber (07) is capable of allowing the carrier (04) held by the holder (01) to be inserted into the desorption chamber (07) from a first end of the desorption chamber (07); and part of the carrier (04) is held by the holder (01) when the desorption chamber (07) is heated to thermally desorb the absorbed sample on the carrier (04), the holder (01) seals the first end of the desorption chamber (07), and at least a part of the carrier (04) is sealed within the desorption chamber (07).

Description

Thermal desorption sampling device, thermal desorption equipment and ion mobility spectrometer detection equipment

This application claims the priority of the Chinese patent application 202010475289.8 filed on May 29, 2020, the content of which is incorporated herein by reference.

Technical field

The present invention relates to the field of security inspection, in particular to thermal desorption sampling devices, thermal desorption equipment and ion mobility spectrometer detection equipment.

Background technique

As a broad-spectrum analysis technology, ion mobility spectroscopy detection technology has the advantages of fast detection speed, high sensitivity, easy miniaturization, and low power consumption. It can detect different shapes such as letters, packages and luggage in a few seconds. Explosives and drugs in objects of a small size can also be used to detect human body carry-on objects. In the current security market, ion mobility spectroscopy detection technology is mainly used to detect dangerous goods (such as explosives and drugs). In ion mobility spectrometry instruments, there are thermal desorption sampling devices, which can vaporize and desorb incoming solid particles or gases. After that, the vaporized sample molecules enter the ionization zone under the guidance of the gas flow and are ionized. The sample ions enter the migration zone, and the molecular identification is realized according to the difference of flight time.

The thermal desorption sampling device is an indispensable component used in the ion mobility spectrometer detector. Its performance directly determines the sampling efficiency and the overall performance of the ion mobility spectrum. The existing thermal desorption sampling devices all use membrane injection methods. Sample, membrane sampling cannot guarantee that the sample enters the device completely, which will reduce the sensitivity of the device.

Summary of the invention

The embodiment of the present disclosure provides a thermal desorption sampling device, including:

Holder, used to hold the carrier for adsorbing the sample; and

A desorption cavity, defining a closed desorption cavity space for heating the carrier that adsorbs the sample in the desorption cavity space so that the sample is desorbed from the carrier;

Wherein, the desorption cavity can allow the carrier held by the holder to be inserted into the desorption cavity from the first end of the desorption cavity, and when the desorption cavity is heated to thermally desorb the sample adsorbed on the carrier, A part of the carrier is clamped by a holder, which seals the first end of the desorption cavity, and at least a part of the carrier is sealed in the desorption cavity.

In one embodiment, the thermal desorption sampling device further includes a closed cavity defining an internal space, and the desorption cavity is in the internal space of the closed cavity;

The closed cavity includes a sample inlet, and the carrier can be inserted into the desorption cavity through the sample inlet and the first end of the desorption cavity connected to the sample inlet.

In one embodiment, the holder includes a first holding head and a second holding head, the first holding head and the second holding head can hold the carrier by being close to each other, and the first holding head At least a part of the outer surface of the first end of the clamping head and the outer surface of the first end of the second clamping head has a slope, so that the first clamping head and the second clamping head can clamp the carrier and insert the carrier into the When the inlet of the cavity is sealed, the inclined first end outer surface of the first clamping head located on the opposite side of the carrier and the first end outer surface of the second clamping head together form a surface contact and sealing place. The injection port of the closed cavity.

The first end of the first clamping head is provided with a first gasket, the first end of the second clamping head is provided with a second gasket, and at least a part of the outer surface of the first end of the first gasket has an inclined surface and a second gasket. At least a part of the outer surface of the first end of the gasket has a slope, so that when the first gasket and the second gasket clamp the carrier and insert the carrier into the sampling port of the closed cavity, the first gasket of the first gasket The surface formed by the inclined surface portion of the outer surface of one end and the inclined surface portion of the outer surface of the first end of the second sealing gasket together contacts and seals the injection port of the closed cavity.

In one embodiment, the holder further includes a first holding handle and a second holding handle, which constitute reverse tweezers, so that the first ends of the first holding handle and the second holding handle are respectively connected to the first end of the first holding handle and the second holding handle. The clamping head is connected to the second end opposite to the first end of the second clamping head, and the second end opposite to the first end of the first clamping handle and the second clamping handle are connected together; the first clamp The holding handle and the second holding handle can make the first holding head and the second holding head abut against each other so as to hold the carrier.

In one embodiment, the thermal desorption sampling device further includes: a first heating film and a second heating film, respectively attached to the opposite side surfaces of the desorption chamber.

The carrier is a test paper.

On the one hand, a thermal desorption device is also provided, including:

In the above thermal desorption sampling device, the desorption chamber further includes an air inlet, which is arranged on a part of the desorption chamber located in the closed cavity near the first end of the desorption chamber, and is used to introduce gas into the desorption chamber. Cavity; and

The sampling pipeline is configured to introduce the gas including the sample from the desorption chamber in the first state.

In one embodiment, the sampling pipeline includes:

Heating pipe,

The solenoid valve fluidly connects the heating tube and the desorption chamber, and is used to introduce the gas including the sample in the desorption chamber through the NC end of the solenoid valve in the first state of the sampling pipeline, and send it from the COM end of the solenoid valve to the heating tube In the sampling tube, so that the heating tube heats the gas including the sample;

Among them, the COM end of the solenoid valve is disconnected from the NO end of the solenoid valve in the first state of the sample injection pipeline.

In one embodiment, the sampling pipeline includes:

The carrier gas tube of the heating tube is used to receive the carrier in the second state of the sampling pipeline so that the heating tube heats the carrier gas, and guides the carrier gas to the NO end of the solenoid valve and to the COM end of the solenoid valve ；

Wherein, the COM end of the solenoid valve is disconnected from the NC end of the solenoid valve in the second state of the sample injection pipeline.

In one embodiment, the air inlet pipeline further includes a blowback port for blowing air into the air inlet pipeline in the second state of the sampling pipeline, so that the air flows from the NC end of the solenoid valve to the desorption chamber along the air inlet pipeline Blow in the direction to clean the air inlet pipe.

In an embodiment, the sample inlet tube and/or the carrier gas tube of the heating tube are a plurality of pores distributed in the heating tube body of the heating tube.

In an embodiment, the heating tube includes:

Heating tube body,

The heating element is arranged in the heating tube body;

The temperature measuring element is arranged in the heating tube body; and

The heat preservation element covers the heating tube body of the heating tube in order to reduce heat loss.

On the one hand, an ion mobility spectrometer detection device is provided, which includes:

The above-mentioned thermal desorption equipment; and

Ion mobility spectrometer, used to detect the nature of the sample;

Wherein, in the second state of the thermal desorption device, a part of the carrier gas of the ion mobility spectrometer is introduced into the carrier gas pipeline.

Description of the drawings

Fig. 1 is a schematic diagram of a thermal desorption device according to an embodiment of the present disclosure, the upper figure is a schematic cross-sectional view along the line A-A, and the lower figure is a schematic cross-sectional view along the line B-B of the upper figure;

Figure 2 is a schematic cross-sectional view of a heating tube according to an embodiment of the present disclosure, the drawing is a schematic cross-sectional view along the line B-B, and the right figure is a schematic cross-sectional view along the line A-A in the left figure;

Fig. 3 is a schematic diagram of a pipeline of a thermal desorption device according to an embodiment of the present disclosure, in which the air inlet pipeline is in a first state;

Fig. 4 is a schematic diagram of a pipeline of a thermal desorption device according to an embodiment of the present disclosure, wherein the intake pipeline is in a second state;

Fig. 5 and Fig. 6 are respectively partial enlarged views of Fig. 1.

Detailed ways

The present disclosure has multiple embodiments, which are provided to better understand the technical solutions and inventive concepts of the present disclosure in conjunction with the accompanying drawings. It should be understood that the embodiments of the present disclosure are not intended to limit the scope of the present disclosure.

Fig. 1 shows a specific product according to an embodiment of the present disclosure. However, it should be noted that multiple components of the specific product shown in Fig. 1 are not necessary, and other embodiments of the present disclosure may have the same features as those shown in Fig. 1 The different structures and different components are shown. FIG. 1 is only an example of the technical solution of the present disclosure.

The embodiment of the present disclosure provides a thermal desorption sampling device. With reference to Figures 1 and 5-6, the thermal desorption sampling device may include: a holder 01, which is used to hold a carrier 04 for adsorbing the sample; and a desorption chamber 07, which defines a closed desorption chamber space for use in the desorption chamber space The carrier 04 that adsorbs the sample is heated inside so that the sample is desorbed from the carrier 04; wherein, the desorption cavity 07 can allow the carrier 04 held by the holder 01 to pass from the first end of the desorption cavity 07 (as shown in FIG. 1 The left end) is inserted into the desorption chamber 07, and when the desorption chamber 07 is heated to thermally desorb the sample adsorbed on the carrier 04, a part of the carrier 04 is clamped by the holder 01, the The holder 01 seals the first end of the desorption cavity 07, and at least a part of the carrier 04 is sealed in the desorption cavity 07. It should be noted that the thermal desorption sampling device provided in this embodiment is different from the mechanism shown in FIG. 1, and FIG. 1 is only to help understand this embodiment. The latter embodiment may also have only the part of the structure shown in Fig. 1.

In this embodiment, the carrier 04 can be a test paper, such as Nomex (aromatic polyamide) paper, which has fine cavities on the surface, which is easy to adsorb samples, is resistant to high temperatures, and can maintain its original characteristics at 250°C. , The test paper is used to wipe the surface of various tested samples. After wiping, it is inserted into the thermal desorption chamber, and the sample is vaporized for analysis. According to this embodiment, the first end of the desorption chamber 07 allows the carrier 04 clamped by the holder 01 to enter the desorption chamber 07, and the desorption chamber 07 is sealed by the holder 01, where the closed refers to the desorption chamber 07 The first end is sealed, and the other parts of the desorption chamber 07 are sealed. That is to say, the holder of the present disclosure can be a separate component from the desorption chamber 07, and is used solely to hold the carrier for sampling test paper and the like, and then inserted into the desorption chamber, thereby allowing convenient sampling through the test paper, and at the same time conveniently The holder is fed into the desorption chamber 07, which makes the actual inspection operation easy and quick; the holder 01 holding the carrier 04 can be directly inserted into the desorption chamber, and the closed desorption chamber starts to desorb the sample, which has good convenience.

In an embodiment, the thermal desorption sampling device may further include a closed cavity defining an internal space, and the desorption cavity is in the internal space of the closed cavity. For example, as shown in FIGS. 1 and 5-6, a space is defined between the desorption cavity and the inner cavity wall of the closed cavity, that is, the desorption cavity does not contact the inner cavity wall of the closed cavity. The closed cavity includes a sampling port 03, and the carrier can be inserted into the desorption cavity 07 through the sampling port 03 and the first end of the desorption cavity 07 connected to the injection port 03. In this embodiment, the first end of the desorption cavity 07 (the left end in FIG. 5) is connected to the closed cavity, or in other words, the first end of the desorption cavity 07 is connected to the sampling port 03 of the closed cavity. In this embodiment, the holder 01 may not be directly connected to the first end of the desorption cavity 07, and the holder 01 may be connected to the injection port 03 of the closed cavity when the carrier is inserted into the desorption cavity 07. For example, in one embodiment, the holder 01 includes a first holding head 012 and a second holding head 013, and the first holding head 012 and the second holding head 013 can pass close to each other so that the The carrier 04 is clamped. In an embodiment, the holder 01 further includes a first gasket 014 and a second gasket 015, the first gasket 014 and the second gasket 015 are respectively arranged on the first clamping head 012 and the second clamp Holding the first end of the head 013 (the right end in FIG. 5, the end close to the closed cavity), the first gasket 014 and the second gasket 015 can be formed of elastic materials such as rubber, so as to have a better sealing function. The first gasket 014 and the second gasket 015 clamp the carrier of the sample. The outer surface of the first end of the first gasket 014 (the right end in FIG. 5, the end close to the closed cavity) and at least a part of the outer surface of the first end of the second gasket 015 are inclined to facilitate the first sealing When the gasket 014 and the second gasket 015 clamp the carrier and insert it into the injection port of the closed cavity, the slope part of the outer surface of the first end of the first gasket 014 and the outer surface of the first end of the second gasket 015 The inclined surface part of the surface together constitutes a surface that contacts and seals the flared part of the injection port 03 of the airtight cavity. Since at least a part of the outer surface of the first end of the first sealing gasket 014 and the outer surface of the first end of the second sealing gasket 015 has an inclined surface, when the first clamping head 012 and the second clamping head 013 are respectively disposed thereon When the first sealing gasket 014 and the second sealing gasket 015 are inserted into the injection port 03 of the closed cavity, an interference fit can be realized to seal the injection port of the closed cavity, that is, with the first clamping head The first end of the 012 and the first end of the second clamping head 013 are inserted forward, and the inclined surface applies force to the injection port of the closed cavity so that the contact interface can be tightly sealed. In another embodiment, unlike the situation shown in the figure, at least a part of the first clamping head 012 and the second clamping head 013, for example, the first end is formed of an elastic material such as rubber, and the first clamping head 012 At least a part of the outer surface of the first end of the first end has a slope, at least a part of the outer surface of the first end of the second clamping head 013 has a slope, and the slope part of the first end outer surface of the first clamping head 012 and the second clamping The inclined surface part of the outer surface of the first end of the head 013 together constitutes a surface contacting and sealing the flared part of the injection port 03. This embodiment thus realizes quick insertion and sealing, facilitates operation, isolates external air, and reduces interference.

The holder 01 may also include a gasket 016 made of, for example, stainless steel. The left end of the gasket 016 (the end close to the first clamping head and the second clamping head) extends into the first clamping head and the second clamping head. The space between is used to support the test paper. The gasket 016 is preferably fixedly connected to one of the first clamping head 012 and the second clamping head 013. Of course, the gasket 016 may not be fixedly connected to the clamping head but only by the first clamping head 012 and the second clamping head. The elastic force between the head 013 is clamped.

In one embodiment, the holder 01 further includes a first holding handle 011A and a second holding handle 011B, which constitute reverse tweezers, that is, the first holding handle 011A and the second holding handle 011B The first end (the end on the right side of the first clamping handle 011A and the second clamping handle 011B in FIG. 1) is respectively opposite to the first end of the first clamping head 012 and the second clamping head 013. The two ends (that is, the end on the left side of the first clamping head 012 and the second clamping head 013 in FIG. 1) are connected, and the first clamping handle 011A and the second clamping handle 011B are opposite to their first ends The second ends (the left ends of the first clamping handle 011A and the second clamping handle 011B in FIGS. 1 and 5) are connected together. With this structure, the first clamping handle 011A and the second clamping handle 011B can make the first clamping head 012 and the second clamping head 013 abut against each other so as to clamp the carrier. In this embodiment, the first clamping handle 011A and the second clamping handle 011B are convenient for users to grasp, and the first clamping handle 011A and the second clamping handle 011B can make the first clamping head 012 and the second clamping The heads 013 abut against each other in order to clamp the carrier, without the user's force holding, and it is convenient to clamp the test paper.

In one embodiment, the thermal desorption sampling device further includes a first heating film 076 and a second heating film 074, which are respectively attached to the opposite side surfaces of the desorption chamber 07. Other heating elements, such as heating wires, can be used, wound or embedded on the opposite side surface of the desorption chamber 07.

The thermal desorption sampling device of the present disclosure may also include other elements for connecting, fixing, and sealing. For example, the sealing ring may be arranged around the air inlet. Details are not repeated here, and examples will be given later in the present disclosure to help understand the technical solutions of the present disclosure.

An aspect of the present disclosure also provides a thermal desorption device. The thermal desorption equipment includes the above-mentioned thermal desorption sampling device and a sampling pipeline, and is configured to introduce a gas including a sample from the desorption chamber 07 in the first state. In this embodiment, the desorption chamber 07 of the thermal desorption sampling device further includes an air inlet 072, which is arranged on a part of the desorption chamber 07 that is located in the closed cavity and close to the first end of the desorption chamber 07 , Used to introduce gas into the desorption chamber 07. In this embodiment, the gas inlet 072 is different from the inlet used to introduce the carrier. This allows the sample on the carrier to be thermally desorbed while introducing, for example, pulse gas from the gas inlet 072, and the sample is sent to the detection device for detection. . The air inlet 072 is shown as the upper side wall of the desorption chamber 07 in FIG. 1; however, the air inlet 072 may be provided on the lower side wall of the desorption chamber 07.

In one embodiment, the sample injection pipeline includes: a heating tube 13; a solenoid valve 11, which fluidly communicates the heating tube 13 with the desorption chamber 07, and is used to remove the sample in the desorption chamber 07 in the first state of the sample injection pipeline. The gas is introduced through the NC end of the solenoid valve 11, and sent from the COM end of the solenoid valve 11 to the sampling tube 135 of the heating tube 13, so that the heating tube 13 heats the gas including the sample. In the first state of the sampling pipeline, the COM end of the solenoid valve 11 is disconnected from the NO end of the solenoid valve 11. In this embodiment, the gas introduced from the gas inlet 072 is pulsed gas, and the sample in the desorption chamber 07 can be quickly introduced into the heating tube 13; at this time, as shown in FIG. 3, the sampling pipeline is at In the first state, the COM terminal of the solenoid valve 11 is disconnected from the NO terminal of the solenoid valve 11, and the gas containing the sample cannot enter the NO terminal. At the same time, the carrier gas tube 136 in the ion mobility spectrometer in FIG. 3 is disconnected, and the reverse blowing The gas blowback port 112 is disconnected from the NC end.

After the sample has entered the heating tube 13, the sample can enter the detection device, that is, enter, for example, an ion mobility spectrometer for detection. The sampling pipeline includes a carrier gas tube 136 of a heating tube for receiving the carrier in the second state of the sampling pipeline so that the heating tube heats the carrier gas, and guides the carrier gas to the NO end of the solenoid valve 11 and To the COM terminal of the solenoid valve 11. In the second state of the sample injection pipeline, the COM end of the solenoid valve 11 is disconnected from the NC end of the solenoid valve 11, and the gas and sample introduced at the air inlet 072 cannot enter the heating tube 13 at this time. The carrier gas can circulate in the carrier gas pipe 136, the NO end of the solenoid valve, the COM end of the solenoid valve, and the gas path of, for example, an ion mobility spectrometer.

In the second state of the sample injection pipeline, the reverse blowing port 112 of the reverse blowing can be communicated with the NC end. The blowback port 112 blows air into the air inlet pipe. At this time, the NC end of the solenoid valve is disconnected from the COM end of the solenoid valve. The air is blown from the NC end of the solenoid valve 11 along the inlet pipe toward the desorption chamber 07 to clean the inlet pipe. . The gas flow of the reverse blowing is opposite to the gas flow of the inlet, so the reverse gas can clean the inlet pipe, sweep the residual sample in the inlet pipe from the inlet pipe and the desorption chamber 07, avoiding the next sample injection Bring pollution.

The air intake pipeline may also include a pump 25, which pumps the gas into the blowback port 112 when the gas is blown in the reverse direction.

In Figures 3 and 4, the dashed line indicates that this part of the pipeline is disconnected.

In one embodiment, as shown in FIG. 2, the heating tube 13 has a heating tube body 133, and the sampling tube 135 and/or the carrier gas tube 136 are multiple air holes distributed in the heating tube body 133 of the heating tube 13. A plurality of air holes can allow gas to be transferred through each of the air holes, thereby increasing the contact between the gas and the heating tube body of the heating tube, and improving the heat exchange rate. The heating tube may further include: a heating element 1310, which is arranged in the heating tube body 133; a temperature measuring element 139, which is arranged in the heating tube body 133; and a heat preservation element 134, which covers the heating tube body 133 of the heating tube so that Reduce heat loss. The heating element is arranged in the heating tube body 133. The embedded heating element can realize the rapid temperature rise of the heating tube body 133. Because the temperature measuring element 139 is configured, the temperature control of the heating tube body 133 can be realized. The heat preservation element 134 can improve thermal efficiency. The setting of the heating tube 13 can allow the sample-containing gas to be tested to have a desired temperature, thereby improving the detection efficiency; and, the sample-containing gas has a predetermined temperature, thereby improving the detection accuracy. In addition, at a certain temperature, the sample is not easy to adhere to the pipe wall of the inlet pipe, which improves the equipment's ability to avoid contamination.

Another aspect of the present disclosure provides an ion mobility spectrometer detection device, including: the aforementioned thermal desorption device; and an ion mobility spectrometer. Ion mobility spectrometers are well-known devices for detecting the properties of samples. In this embodiment, in the second state of the thermal desorption device, a part of the carrier gas of the ion mobility spectrometer is introduced into the carrier gas pipeline 36. The structure and working mode of the ion mobility spectrometer are well-known, so I won’t go into details here. For example, in the ion mobility spectrometer shown in FIGS. 3 and 4, the carrier gas circulates in the migration pipe 18, the exhaust buffer tank 19, the first pump 20, the intake buffer tank 21, and the first filter 22; It also enters the carrier gas pipe 136 of the heating pipe 13 through the carrier gas pipe 36 and enters the migration pipe 18 together with the sample-containing gas.

In the following, specific products according to the embodiments of the present disclosure are taken as examples to illustrate the technical solutions of the present disclosure.

As shown in Fig. 1, the test paper holder 01 may include clamping tweezers 011, a first clamping head 012, a second clamping head 013, a first sealing gasket 014; a second sealing gasket 015, a (stainless steel) gasket 016 composition. The clamping tweezers 011 are reverse tweezers, composed of a first clamping handle 011A and a second clamping handle 011B. Their material is generally spring steel. The ends of the first clamping handle 011A and the second clamping handle 011B are welded Together, the free front end of the tweezers is in the closed state. After pressing the first gripping handle 011A and the second gripping handle 011B by hand, the front end opens.

The first clamping head 012 is fixed to the front end of the first clamping handle 011A by screws, and the first sealing gasket 014 and washer 016 are fixed on the first clamping head 012 by screws. The main function of the gasket 016 is to wipe the test paper 04 It plays a supporting role when wiping the surface of the measured object, increasing the wiping force and improving the wiping efficiency; the second clamping head 013 is fixed on the front end of the second clamping handle 011B by screws, and the second gasket 015 is fixed on the second clamping by screws On the head 013, a test paper positioning groove is provided on the second clamping head 013.

The first gasket 014 and the second gasket 015 can be inserted into the injection port 03 to seal the injection port 03, and they can be soft materials such as silica gel or rubber.

The photoelectric switch 02 is generally a slot-type photoelectric switch, which is fixed on the injection port 03 and has a light-transmitting hole on the injection port 03. Its main function is to block the light of the photoelectric switch 02 when the wipe test paper 04 is inserted into the injection port 03. After the signal, the photoelectric switch 02 sends a signal to the device to start the sampling operation.

The injection port 03 can be made of temperature-resistant and heat-insulating materials such as PTFE or PEEK. It mainly prevents hands from directly contacting the thermal desorption chamber 07 and can play a guiding role; it can be omitted, that is, the holder can be directly connected to the desorption chamber. 07 connection, the inclined surface of the first end of the first clamping head 012 and the second clamping head 013 can be connected to the desorption cavity 07 to seal the desorption cavity 07.

In FIG. 1, the closed cavity can be formed by a sealed box 05, a bottom plate 09, a side plate 15 and a sample inlet 03. Wiping the test paper 04 requires high temperature to desorb the sample, so the desorption chamber 07 needs to be heated. In order to maintain heat and reduce energy loss, they should be a kind of temperature-resistant and heat-insulating materials such as PTFE and PEEK and not easy to release odors; In order to further heat insulation and reduce energy loss, the sealing box 04, the second bottom plate 09 and the side plate 09 are respectively fixed with a sealed box insulation cotton 08, a bottom plate insulation cotton 10, and a side plate insulation cotton 16, which are generally resistant to heat. A soft thermal insulation material that keeps heat and does not release odor easily.

The thermal desorption cavity 07 may be provided with a sealing gasket 071, an air inlet 072, a thermal desorption cavity 073, a second heating film 074, a first heating film fixing clip 075, a first heating film 076, and a second heating film fixing clip 077, filter screen 078, air outlet 079, sealing ring 0710, sealing gasket 0711.

The thermal desorption cavity 073 is composed of a first desorption cavity 073A, a second desorption cavity 073B and a desorption cavity tail plate 073C by welding and other methods. The thermal desorption cavity 073 is mainly used to heat and vaporize the sample on the surface of the test paper 04. There may be multiple air passages on the desorption chamber tail plate 073C. When the surfaces of the first desorption chamber part 073A and the second desorption chamber part 073B are blown back through the air outlet 079, dead spots are reduced and the cleaning speed is improved.

The first and second surfaces of the thermal desorption chamber 073 are respectively attached with a first heating film 076 and a second heating film 074, which are clamped by a heating film fixing clip one 075 and a heating film fixing clip two 077, the first heating film 076 And the second heating film 074 is a heating element with its own temperature measurement, which can control the heating temperature of the desorption chamber. Other connection methods may be used to attach the first heating film 076 and the second heating film 074 to the outer surface of the thermal desorption cavity 073.

The gasket 071 is used to seal the inlet 03 and the thermal desorption chamber 073, and should be made of high temperature resistant soft materials such as silica gel, fluoro rubber, and perfluoro rubber.

The isolation column 06 is mainly used to fix the thermal desorption chamber 073 and the injection port 03. The isolation column 06 should be made of temperature-resistant and heat-insulating materials such as polytetrafluoroethylene and PEEK to reduce energy loss and reduce the surface of the injection port 03. temperature.

The air inlet joint 072 is screwed on the first desorption chamber 073A. The air inlet joint 072 should have a gasket to ensure that the air inlet joint 072 and the first desorption chamber 073A are sealed. The gasket should be resistant to high temperature. The air port joint 072 is generally a pagoda head structure.

The air inlet connector 072 is connected to the outlet of the second filter 23 through a PTFE tube. The PTFE tube should be wound around the thermal desorption chamber 07 and connected to the outlet of the second filter 23 to ensure that it enters the thermal desorption chamber 073 The gas is hot, which improves the sensitivity of the device.

The inlet of the second filter 23 is in communication with the air, and is mainly filled with filtering agents such as silica gel, activated carbon, molecular sieve, etc., with the purpose of filtering water vapor and organic matter in the air, and providing clean sample gas for the thermal desorption chamber 073.

The filter screen 078 is placed in the desorption chamber tail plate 073C, and is mainly used to block dust, wool and other sundries in the air. The filter screen 078 should be made of stainless steel, sintered copper and other materials.

The air outlet connector 079 is fixed on the desorption chamber tail plate 073C by threads. The air outlet connector 079 should have a gasket to ensure that the outlet connector 079 is sealed with the desorption chamber tail plate 073C. The gasket should be resistant to high temperatures.

The other end of the air outlet connector 079 is inserted into the NC port 111 of the solenoid valve seat 113, and double sealing is realized by the sealing ring 0710 and the sealing gasket 0711. The sealing ring 0710 and the sealing gasket 0711 should be high temperature resistant and not easy to release organic matter soft materials .

The solenoid valve 11 is composed of an NC port 111, a blowback port connector 112, a valve seat 113, an NO port connector 114, a valve body 115, and a COM port connector 116.

The valve body 115 is a two-position three-way pulse solenoid valve. The opening and closing time of the solenoid valve is only a few ms, which can realize pulse injection. It is an isolation solenoid valve to ensure that the sample does not contact the valve core. NO terminal, COM terminal, NC terminal, when the solenoid valve is not energized, COM terminal and NO terminal are connected, NC terminal is closed, when the solenoid valve is energized, COM terminal and NC terminal are connected, and NO terminal is closed.

The valve body 115 is fixed on the valve seat 113 by screws, and the blowback port connector 112, the NO port connector 114, and the COM port connector 116 are fixed on the valve seat 113 by threads. The threaded end should have a gasket to ensure the seal between the connector and the valve seat 113. , The other end is the structure of the pagoda head; the blowback port connector 112, the NO port connector 114, and the COM port connector 116 communicate with the NC, NO, and COM ends of the solenoid valve body 115 through the air holes in the valve seat 113, respectively.

The valve seat 113 is fixed on the bottom plate 09 by screws.

The pagoda head end of the blowback connector 112 is connected to the outlet of the on-off solenoid valve 24 through a PTFE tube. The PTFE tube can be reserved in the sealed box for a certain distance, and then connected to the outlet of the on-off solenoid valve 24 outside to ensure access The back blow air of the thermal desorption chamber 073 is hot air, which improves the cleaning speed.

The on-off solenoid valve 24 should be a pulse solenoid valve, which can open and close the solenoid valve within a few mm, so as to realize the pulse back-blowing airflow and increase the speed of the back-blowing airflow to sweep the inner surface of the thermal desorption chamber 073 to improve the equipment The cleaning speed.

The inlet of the on-off solenoid valve 24 is connected with the outlet of the second pump 25, the inlet of the second pump 25 is connected with the outlet of the third filter 26, and the third filter 26 is in communication with air.

The main function of the second pump 25 is to provide power for the blowback gas.

The third filter 26 is mainly filled with filtering agents such as silica gel, activated carbon, molecular sieve, etc., with the purpose of filtering water vapor and organic matter in the air, and providing clean back-blowing gas.

The main function of the heating tube fixing plate 12 is to fix the heating tube 13 on the sealed box 5, and it should be made of heat-insulating and temperature-resistant materials such as PTFE and PEEK.

The heating tube 13 mainly includes a carrier gas tube outlet connector 131, a sample tube inlet connector 132, a heating tube body 133, a thermal insulation cotton 134, a sample tube 135, a carrier gas tube 136, a sample tube outlet connector 137, a carrier gas tube inlet connector 138, and a test tube. It is composed of temperature element 139 and heating rod 1310.

The heating tube body 133 is a metal material that is easy to conduct heat. For example, a heating element 1310 in the form of a heating rod is placed to heat the heating tube body. , Such as thermal insulation cotton, to reduce energy loss.

The sampling tube 135 and the carrier gas tube 136 are composed of a plurality of tiny pores processed on the heating tube body 133. The diameter of the tiny pores is about φ. Therefore, the sampling tube 135 and the carrier gas tube 136 can be regarded as pore bundles respectively. The gas passing through the sampling pipe 135 and the carrier gas pipe 136 fully contacts the surface of the heating pipe 133, and the sample is fully vaporized.

The two ends of the sampling pipe 135 are respectively connected with a sampling pipe inlet connector 132 and a sampling pipe outlet connector 137, and both ends of the carrier gas pipe 136 are respectively connected with a carrier gas pipe outlet connector 131 and a carrier gas pipe inlet connector 138.

One end of the sampling tube inlet connector 132, the sampling tube outlet connector 137, the carrier gas tube outlet connector 131 and the carrier gas tube inlet connector 138 are screwed into the heating tube body 133 through threads. The threaded ends should have gaskets to ensure that the joints are connected to the heating tube body. For the 133 seal, the gasket should be a soft material that is resistant to high temperature and does not easily release odors, and the other end is the structure of the pagoda head.

The sample inlet connector 132 is connected to the COM port connector 116 of the solenoid valve 11 through a PTFE tube, and the sample inlet connector 137 is connected to the sample inlet of the migration tube 18 through a PTFE tube.

The carrier gas pipe outlet connector 131 is connected to the NO port connector 114 of the solenoid valve 11 through a PTFE pipe, and the carrier gas pipe inlet connector 138 is connected to the outlet of the first filter 22.

The ion mobility spectrometer mainly consists of a migration tube 18, an exhaust buffer tank 19, a first pump 20, an intake buffer tank 21, and a first filter 22.

The migration tube 18 has three connectors: migration gas, exhaust gas, and injection port, which are respectively connected to the outlet of the first filter 22, the inlet of the exhaust buffer tank 19, and the NO port connector 114 of the injection solenoid valve 11.

The main function of the migration tube 18 is to detect the vaporized sample coming in from the injection port.

The first pump 20 provides power for the circulation of gas, generally a diaphragm pump; the main purpose of the exhaust buffer tank 19 and the intake buffer tank 21 is to buffer the fluctuation of the air flow of the first pump 20 of the diaphragm; the main purpose of the first filter 22 is In order to purify the sample carrier gas and migration gas of the migration tube, filter agents such as silica gel, activated carbon, molecular sieve, etc. are generally filled; the indicator light 14 is fixed on the injection port 2 to reflect the state of the thermal desorption system;

The fan 17 is fixed on the bottom plate 09 to cool the valve body 115.

The following describes the entire thermal desorption sampling process:

Pinch the end of the wipe test paper 04 with your hand, and press the holding tweezers 011 with the other hand to open the tweezers, and put the wipe test paper 04 into the second holding head 013 and connect it to the second holding head 013. Align the positioning grooves, and then loosen the gripping tweezers 011; hold the gripping tweezers 011, wipe the test paper 04 downwards and wipe the surface of the object to be tested;

After wiping the surface of the tested object, insert the test paper holder 01 into the sample inlet 03, and the photoelectric switch 02 senses

The light signal is blocked by the wipe test paper 04, and a signal is sent to the main control board to start the thermal desorption sampling process, and the second pump 25 is powered off;

The first gasket 014 and the second gasket 015 of the test paper holder 01 are in interference fit with the injection port 03 to seal the injection port 03 to ensure that the thermal desorption cavity 073 forms a closed cavity;

Wait 1-10s for the sample on the test paper 04 to be fully vaporized, energize the solenoid valve body 115 for 50-500ms, the COM terminal and the NC terminal are connected, the NO terminal is closed, and the negative pressure formed by the migration tube 18 is caused by the first pump 20 Inhale the clean gas from the inlet connector 072 and the sample into the sampling tube 135, and the sampling is completed;

After the sampling is completed, enter the sampling state, pull out the test paper holder, the solenoid valve body 115 is powered off, the COM end is connected to the NO end, the NC end is closed, the carrier gas pipeline 36 is connected to the sampling pipe 135, and the carrier gas will be The gas in the sampling tube 135 is sent to the migration tube 18 for detection, the second pump 25 is energized and turned on, the on-off solenoid valve 24 is in a pulse state, and pulsed back-purge gas is supplied to the thermal desorption chamber 073 to purge the thermal desorption chamber Body 073, clean thermal desorption chamber 073.

It should be noted that the wording "comprise" does not exclude other elements or steps, the wording "a" or "one" does not exclude a plurality; "upper", "lower", "bottom", "upper", "lower" are merely It indicates the orientation of the components in the illustrated structure, rather than limiting their absolute orientation; “first” and “second” are used to distinguish the names of different components, not for ordering or indicating importance or priority. In addition, any element reference signs in the claims should not be construed as limiting the scope of the present disclosure.

Although some embodiments of the present general inventive concept have been shown and described, those of ordinary skill in the art will understand that changes can be made to these embodiments without departing from the principle and spirit of the present general inventive concept. The scope is defined by the claims and their equivalents.

Claims

A thermal desorption sampling device, including:

Holder (01), used to hold the carrier for adsorbing the sample; and

The desorption cavity (07) defines a closed desorption cavity space for heating the carrier (04) that adsorbs the sample in the desorption cavity space so that the sample is desorbed from the carrier;

Wherein, the desorption cavity (07) can allow the carrier held by the holder (01) to be inserted into the desorption cavity from the first end of the desorption cavity (07), and be heated in the desorption cavity for thermal desorption When the sample is adsorbed on the carrier, a part of the carrier is held by a holder, and the holder seals the first end of the desorption chamber (07), and at least a part of the carrier is sealed in the In the desorption chamber (07).
The thermal desorption sampling device according to claim 1, further comprising a closed cavity defining an internal space, and the desorption cavity is in the internal space of the closed cavity;

The closed cavity includes a sample inlet (03), and the carrier can be inserted into the desorption cavity (07) through the sample inlet and the first end of the desorption cavity (07) connected to the sample inlet.
The thermal desorption sampling device according to claim 2, wherein the holder (01) comprises a first holding head (012) and a second holding head (013), the first holding head ( 012) and the second clamping head (013) can clamp the carrier by being close to each other.
The thermal desorption sampling device according to claim 3, wherein:

At least a part of the outer surface of the first end of the first clamping head (012) and the outer surface of the first end of the second clamping head (013) has a slope, so that the first clamping head (012) and the second clamping head (012) When the clamping head (013) clamps the carrier and inserts it into the injection port of the closed cavity, the inclined surface part of the first end outer surface of the first clamping head (012) and the second clamping head (013) The surface formed by the inclined surface part of the outer surface of the first end contacts and seals the injection port of the closed cavity; or,

The first end of the first clamping head (012) is provided with a first gasket (014), the first end of the second clamping head (013) is provided with a second gasket (015), the first gasket (014) ) At least a part of the outer surface of the first end has a slope and at least a part of the outer surface of the first end of the second gasket (015) has a slope, so that the first gasket (014) and the second gasket (015) ) When inserting the carrier into the sampling port of the closed cavity, the inclined surface of the first end outer surface of the first gasket (014) and the inclined surface of the first end outer surface of the second gasket (015) The partially formed surface contacts and seals the injection port of the closed cavity.
The thermal desorption sampling device according to claim 3, wherein the holder (01) further comprises a first holding handle (011A) and a second holding handle (011B), which constitute reverse tweezers, so that the first The first ends of the clamping handle (011A) and the second clamping handle (011B) are respectively connected to the second ends of the first clamping head (012) and the second clamping head (013) opposite to the first ends thereof, And the second end of the first clamping handle (011A) and the second clamping handle (011B) opposite to the first end are connected together; the first clamping handle (011A) and the second clamping handle (011B) can The first clamping head (012) and the second clamping head (013) abut against each other to clamp the carrier.
The thermal desorption sampling device according to claim 1, further comprising: a first heating film (076) and a second heating film (074), respectively attached to the opposite side surfaces of the desorption chamber (07).
The thermal desorption sampling device according to claim 1, wherein the carrier is a test paper.
A thermal desorption equipment, including:

The thermal desorption sampling device according to any one of claims 1-7, wherein the desorption chamber (07) further comprises an air inlet (072), which is arranged in the closed cavity of the desorption chamber (07) On the part close to the first end of the desorption chamber (07) for introducing gas into the desorption chamber (07); and

The sampling pipeline is configured to introduce the gas including the sample from the desorption chamber (07) in the first state.
The thermal desorption device according to claim 8, wherein the sampling pipeline comprises:

Heating tube (13),

The solenoid valve (11) fluidly communicates the heating tube (13) with the desorption chamber (07), and is used to pass the sample-containing gas in the desorption chamber (07) through the solenoid valve (11) in the first state of the sampling pipeline The NC end is introduced and sent from the COM end of the solenoid valve (11) to the sampling tube (135) of the heating tube (13), so that the heating tube heats the gas including the sample;

Wherein, the COM end of the solenoid valve (11) is disconnected from the NO end of the solenoid valve (11) in the first state of the sample injection pipeline.
The thermal desorption device according to claim 9, wherein the sampling pipeline comprises:

The carrier gas pipe (136) of the heating pipe (13) is used to receive the carrier in the second state of the sampling pipe so that the heating pipe heats the carrier gas and guides the carrier gas to the NO end of the solenoid valve (11), And lead to the COM terminal of the solenoid valve (11);

Wherein, the COM end of the solenoid valve (11) is disconnected from the NC end of the solenoid valve (11) in the second state of the sample injection pipeline.
According to the thermal desorption device according to claim 9, the air inlet pipeline further includes a blowback port (112) for blowing air into the air inlet pipeline in the second state of the sampling pipeline, so that the air flows from the solenoid valve ( The NC end of 11) is purged along the inlet pipe towards the desorption chamber (07) to clean the inlet pipe.
The thermal desorption device according to claim 10, wherein the sampling tube (135) and/or the carrier gas tube (136) of the heating tube is distributed in the heating tube body (133) of the heating tube (13) Multiple pores.
The thermal desorption device according to claim 9, wherein the heating pipe comprises:

Heating tube body (133),

The heating element (1310) is arranged in the heating tube body (133);

The temperature measuring element (139) is arranged in the heating tube body (133); and

The heat preservation element (134) covers the heating tube body (133) of the heating tube so as to reduce heat loss.
An ion mobility spectrometer detection equipment, including:

The thermal desorption device according to any one of claims 8-13; and

Ion mobility spectrometer, used to detect the nature of the sample;

Wherein, in the second state of the thermal desorption device, a part of the carrier gas of the ion mobility spectrometer is introduced into the carrier gas pipe (136).