Concentration device for gas sample

Abstract

The utility model discloses a concentration device for a gas sample. The concentration device comprises a cold trap tube, a heating mechanism, a cooling mechanism and a protection system, and the cold trap tube can be filled with a solid-phase adsorption material. The heating mechanism comprises an electric heating wire and a temperature sensor. The cooling mechanism comprises a heat dissipation assembly and a refrigeration assembly, the refrigeration assembly comprises a semiconductor refrigeration sheet and two oppositely-arranged heat conduction plates, and the opposite sides of the two heat conduction plates are provided with grooves capable of containing the electric heating wires. And the electric clamping jaw is used for driving the two heat conducting plates to be opened and closed. The protection system comprises a bottom plate, a sealing cover, an air inlet and an air outlet, and the air inlet is used for being externally connected with the inert gas source. According to the concentration device, the water vapor content in the sealing cover is kept in an extremely low state, it is guaranteed that the heat conduction plate cannot be frosted during refrigeration, and the water vapor is prevented from affecting the service life of the electric heating wire.

Description

Technical Field

[0001] The utility model belongs to the technical field of gas analysis equipment, in particular to a gas sample concentration device. Background Art

[0002] A gas sample concentrator is an instrument used to analyze the concentration of specific components (such as sulfides) in emission sources and the atmospheric environment. It is widely used for industrial and medical purposes. A general gas sample concentrator includes a cold trap tube (cold trap tube), a six-way valve, a heating and refrigeration device, and a quantitative gas storage tank. The cold trap tube is usually made of quartz tube. As a cooling device, a low-temperature surface can be obtained through the refrigeration device to condense and capture gas molecules whose condensation point temperature is higher than the temperature of the cold trap tube. Specific gas molecules can also be captured by setting the condensation temperature, which can separate the gas. After the capture is completed, the gas molecules are released into the quantitative gas storage tank by heating for analysis.

[0003] However, in the process of implementing the technical solution in the embodiments of the present application, the utility model of the present application found that the above-mentioned prior art has at least the following technical problems: thick frost will condense on the refrigeration device and the cold trap tube during the refrigeration process, which will affect the normal operation of the device and also affect the service life of the heating wire. Utility Model Content

[0004] The utility model aims to provide a gas sample concentrator capable of preventing frosting in view of the above-mentioned deficiencies in the prior art.

[0005] In order to solve the above technical problems, the technical solution adopted by the utility model is:

[0006] A gas sample concentration device comprises a cold trap tube, a heating mechanism, a cooling mechanism and a protection system.

[0007] The cold trap tube is tubular and can be filled with solid adsorption material.

[0008] The heating mechanism comprises an electric heating wire and a temperature sensor. The electric heating wire is wound around the cold trap tube, and the temperature sensor is closely attached to the electric heating wire.

[0009] The cooling mechanism includes a refrigeration component and a heat dissipation component. The refrigeration component includes two semiconductor refrigeration plates and two oppositely arranged heat-conducting plates. The cold end of the semiconductor refrigeration plate is in contact with the heat-conducting plate. The opposite side of the two heat-conducting plates is provided with a groove that can accommodate the electric heating wire. The heat dissipation component is used for dissipating the heat of the hot end of the semiconductor refrigeration plate.

[0010] The electric clamp is used to drive the opening and closing of the two heat conducting plates.

[0011] The protection system comprises a base plate, a sealing cover, an air inlet and an air outlet, wherein the sealing cover is detachably connected to the base plate, the air inlet is arranged on the base plate, and the air inlet is used for connecting to an external inert gas source.

[0012] Preferably, the air outlet is arranged on the sealing cover, and a one-way valve is provided on the air outlet.

[0013] Preferably, the protection system further comprises a humidity sensor and / or an oxygen sensor, and the humidity sensor and / or the oxygen sensor are fixedly connected to the base plate.

[0014] Preferably, a sealing ring is provided at the lower portion of the sealing cover, and the sealing ring is used for sealing the sealing cover and the bottom plate.

[0015] Preferably, the heat dissipation component includes a water-cooled plate, a water pump, a cooling fan, a cold water drain and a circulation pipe. The water-cooled plate is bonded to the hot end of the semiconductor refrigeration plate, and the water-cooled plate, the water pump and the cold water drain are connected through the circulation pipe.

[0016] Preferably, the inert gas source externally connected to the gas inlet is dry nitrogen.

[0017] Preferably, conversion joints are provided at both ends of the cold trap tube, and the cold trap tube is connected to an external six-way valve and a gas sample delivery pipeline through the conversion joints.

[0018] Preferably, the cold trap tube is a stainless steel tube. A waterproof connector for connecting external cables is provided on the bottom plate.

[0019] The beneficial effect of the utility model is that when the gas sample concentration device is in operation, the cold trap tube is cooled by the semiconductor refrigeration sheet, and when the water vapor content in the sealing cover is higher than the preset value (or when the inert gas is lower than the set value), dry inert gas is injected to keep the water vapor content in the sealing cover at an extremely low state, ensuring that the heat conduction plate will not frost during refrigeration, and preventing water vapor from affecting the service life of the electric heating wire. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of an embodiment;

[0021] Figure 2 is a top view of an embodiment;

[0022] Figure 3 This is a schematic diagram of the embodiment with the sealing cover hidden;

[0023] Figure 4 yes Figure 3 Side view of

[0024] Marking description: 1-cold trap tube, 21-electric heating wire, 22-temperature sensor, 31-refrigeration component, 32-heat dissipation component, 311-semiconductor refrigeration plate, 312-heat conduction plate, 313-groove, 321-water cooling plate, 322-circulation pipe, 4-electric clamp, 51-bottom plate, 52-sealing cover, 53-air inlet, 54-air outlet, 55-check valve, 56-sealing ring, 6-oxygen sensor, 7-conversion joint, 8-waterproof joint. DETAILED DESCRIPTION

[0025] The following is a description of the implementation of the present invention by means of specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0026] like Figures 1 to 4 As shown, a gas sample concentration device includes: a cold trap tube 1, a heating mechanism, a cooling mechanism and a protection system.

[0027] The cold trap tube 1 is tubular, and the interior thereof can be filled with solid-phase adsorption material.

[0028] The heating mechanism comprises an electric heating wire 21 and a temperature sensor 22 . The electric heating wire 21 is wound around the cold trap tube 1 , and the temperature sensor 22 is closely attached to the electric heating wire 21 .

[0029] The temperature sensor 22 is closely attached to the electric heating wire 21 to detect the temperature of the electric heating wire and the cold trap tube 1 in real time. After the electric heating wire 21 is energized, high temperature is rapidly generated. The temperature sensor 22 feeds back the detected temperature to the control circuit, and controls the temperature by controlling the current size, thereby heating and analyzing the cold trap tube 1, desorbing the concentrated sample, and the sample enters the chromatographic injection port along with the carrier gas to complete the injection.

[0030] The cooling mechanism includes a heat dissipation component 32 and a refrigeration component 31. The refrigeration component 31 includes a semiconductor refrigeration plate 311 and two oppositely arranged heat conducting plates 312. The cold end of the semiconductor refrigeration plate 311 is in contact with the heat conducting plate 312. The two heat conducting plates 312 have grooves 313 on opposite sides thereof for accommodating the electric heating wire 21. The heat dissipation component 32 is used for dissipating the heat of the hot end of the semiconductor refrigeration plate 311.

[0031] There are 6 semiconductor refrigeration plates 311 in total, 3 in a group, two groups, one refrigeration plate at the bottom and two refrigeration plates at the top. In this way, the two-stage refrigeration structure can achieve a cold end of -40°C (room temperature 20°C).

[0032] In order to make the cold trap tube 1 reach a lower temperature working environment, a two-stage or multi-stage semiconductor refrigeration sheet 311 is used. It is also possible to use multiple single-stage semiconductor refrigeration sheets 311 to form a multi-stage refrigeration structure. An aluminum plate is attached to the cold end of the last stage semiconductor refrigeration sheet 311 as a heat conduction plate 312.

[0033] The electric clamp 4 is used to drive the opening and closing of the two heat conducting plates 312. When entering the concentration process, the electric clamp 4 is closed, driving the cooling mechanism to close, and the upper and lower heat conducting plates 312 are closed, covering the electric heating wire 21 and the cold trap tube 1, so that the cold end temperature is transferred to the cold trap, and the sample is concentrated.

[0034] The protection system includes a base plate 51, a sealing cover 52, an air inlet 53 and an air outlet 54. The sealing cover 52 is detachably connected to the base plate 51. The air inlet 53 is arranged on the base plate 51 and is used for connecting to an external inert gas source.

[0035] The air outlet 54 is disposed on the sealing cover 52 , and a one-way valve 55 is disposed on the air outlet 54 .

[0036] The protection system further comprises a humidity sensor and an oxygen sensor 6, which are fixedly connected to the bottom plate 51. A sealing ring 56 is provided at the lower part of the sealing cover 52, and the sealing ring 56 is used for sealing the sealing cover 52 and the bottom plate 51.

[0037] The heat dissipation assembly 32 includes a water-cooled plate 321, a water pump, a heat dissipation fan, a cold water row and a circulation pipe 322. The water-cooled plate 321 is attached to the hot end of the semiconductor cooling sheet 311, and the water-cooled plate 321, the water pump and the cold water row are connected through the circulation pipe 322. The semiconductor cooling sheet 311 transfers heat to the water-cooled plate 321, the water pump transfers heat from the water-cooled plate 321 to the cold water row through cooling water, and the heat dissipation fan takes away the heat from the cold water row through airflow to achieve the purpose of heat dissipation.

[0038] The water pump provides power for the entire cooling circulation system. The water cooling plate 321 is made of copper or aluminum alloy or other heat-conducting materials with good thermal conductivity and a smooth surface. It is closely attached to the hot surface of the semiconductor cooling plate 311 to conduct the heat surface temperature. There are multi-channel water flow channels inside. The flowing coolant takes away the temperature from the hot surface of the cooling plate, and dissipates the heat through the cooling fan when flowing through the cold water discharge. This water cooling structure can take away the heat in the sealing cover 52 through the circulation pipe 322, and prevent the heat from accumulating in the sealing cover 52 and affecting the cooling effect.

[0039] The inert gas source externally connected to the gas inlet 53 is dry nitrogen.

[0040] The cold trap tube 1 is provided with conversion joints 7 at both ends, and the cold trap tube 1 is connected to the external gas sample delivery pipeline through the conversion joints 7, and the six-way valve adjusts the delivery route of the gas sample. The cold trap tube 1 is a stainless steel tube. Compared with a quartz tube, a stainless steel tube will not be broken by the action of the clamping claw. A waterproof joint 8 is provided on the bottom plate 51.

[0041] When working, the gas sample concentrator cools the cold trap tube 1 through the semiconductor refrigeration sheet 311, and injects dry inert gas when the humidity sensor detects that the water vapor content in the sealing cover 52 is higher than the preset value (or when the oxygen sensor 6 detects that the inert gas is lower than the set value). The water vapor content in the sealing cover 52 is kept at an extremely low state, ensuring that the heat conducting plate 312 will not frost during cooling, increasing the service life of the electric heating wire 21, and preventing the cold trap tube 1 from bursting during heating.

[0042] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only for explaining the principle of the utility model. The utility model may have various changes and improvements without departing from the spirit and scope of the utility model. These changes and improvements fall within the scope of the utility model to be protected. The scope of protection claimed by the utility model is defined by the attached claims and their equivalents.

[0043] In the description of the present invention, it is necessary to understand that the terms "front", "rear", "left", "right", "center", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the protection content of the present invention.

Claims

1. A gas sample concentration device, characterized in that: include: The cold trap tube (1) is in a tubular shape and can be filled with a solid-phase adsorption material; The heating mechanism comprises an electric heating wire (21) and a temperature sensor (22), wherein the electric heating wire (21) is wound around the cold trap tube (1), and the temperature sensor (22) is closely attached to the electric heating wire (21); A cooling mechanism comprises a refrigeration component (31) and a heat dissipation component (32), wherein the refrigeration component (31) comprises a semiconductor refrigeration plate (311) and two heat conduction plates (312) arranged opposite to each other, the cold end of the semiconductor refrigeration plate (311) is in contact with the heat conduction plate (312), and a groove (313) capable of accommodating the electric heating wire (21) is provided on opposite sides of the two heat conduction plates (312), and the heat dissipation component (32) is used for dissipating the heat of the hot end of the semiconductor refrigeration plate (311); An electric clamp (4) for driving the opening and closing of the two heat conducting plates (312); as well as A protection system comprises a base plate (51), a sealing cover (52), an air inlet (53) and an air outlet (54); the sealing cover (52) is detachably connected to the base plate (51); the air inlet (53) is arranged on the base plate (51); and the air inlet (53) is used for connecting to an external inert gas source.

2. The gas sample concentration device according to claim 1, characterized in that: The air outlet (54) is arranged on the sealing cover (52), and a one-way valve (55) is provided on the air outlet (54).

3. The gas sample concentration device according to claim 1, characterized in that: The protection system further comprises a humidity sensor and / or an oxygen sensor (6), wherein the humidity sensor and / or the oxygen sensor (6) is fixedly connected to the base plate (51).

4. The gas sample concentration device according to claim 1, characterized in that: A sealing ring (56) is provided at the lower part of the sealing cover (52), and the sealing ring (56) is used for sealing the sealing cover (52) and the bottom plate (51).

5. The gas sample concentration device according to claim 1, characterized in that: The heat dissipation component (32) comprises a water cooling plate (321), a water pump, a cold water drain and a circulation pipeline (322); the water cooling plate (321) is bonded to the hot end of the semiconductor refrigeration plate (311); and the water cooling plate (321), the water pump and the cold water drain are connected via the circulation pipeline (322).

6. The gas sample concentration device according to claim 1, characterized in that: The inert gas source externally connected to the gas inlet (53) is dry nitrogen.

7. The gas sample concentration device according to claim 1, characterized in that: Both ends of the cold trap tube (1) are provided with conversion joints (7), and the cold trap tube (1) is connected to a gas sample delivery pipeline via the conversion joints (7).

8. The gas sample concentration device according to claim 7, characterized in that: The cold trap tube (1) is a stainless steel tube.

9. The gas sample concentration device according to claim 1, characterized in that: The bottom plate (51) is provided with a waterproof connector (8) for connecting an external cable.

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