Enrichment and analysis device for trace components in gas detection

Abstract

The utility model relates to the technical field of trace gas detection, in particular to a trace component enrichment and analysis device in gas detection, which comprises a compressor, a condenser, a dry filter, an electronic expansion valve and an evaporator, an outlet of the compressor is connected with a copper pipe, the copper pipe is sequentially connected with a drying filter and an electronic expansion valve through a condenser, the evaporator is formed by tightly and spirally winding the copper pipe, a heat conduction round bar is fixedly arranged in the evaporator in a penetrating mode, a through hole penetrating through the two ends is formed in the heat conduction round bar, and a cold trap pipe is fixedly arranged in the through hole in a penetrating mode. The cold trap tube is filled with an adsorption filler; heating power supplies are applied to the two ends of the cold trap tube, and the heating power supplies are matched with the temperature sensors to control the temperature of the cold trap tube. The device can efficiently and stably realize low-temperature adsorption enrichment and high-temperature desorption of trace gas, so that the detection process of the trace gas is realized, and the device is convenient to use in trace gas detection.

Description

Technical Field

[0001] This utility model relates to the field of trace gas detection technology, specifically to a device for enriching and analyzing trace components in gas detection. Background Technology

[0002] Gas chromatography-flame photometric detector (GC-FPD) can be used to detect trace components in gases, but the trace gases need to be enriched before detection. Taking sulfides as an example, existing GC-FPDs can directly detect concentrations higher than 1.0 mg / m³. 3 The sulfide component in the gas, when the gas sulfide concentration is below 1.0 mg / m³ 3 In such cases, it is necessary to concentrate and enrich the gas sample.

[0003] Existing enrichment methods generally employ cold trap adsorption enrichment, which uses a semiconductor thermoelectric cooler to achieve adsorption and enrichment of trace components, followed by heating with a heating wire to desorb and desorb the enriched trace components, thereby enabling the detection of trace gases. However, this process involves high power consumption of the thermoelectric cooler, requiring a water-cooling system, making it prone to damage and requiring regular maintenance. Furthermore, the thermoelectric cooler needs to operate for extended periods, its surface is prone to frost formation, and a nitrogen purging structure is required, resulting in a complex overall structure and inconvenience for use. To address this, some methods use a compressor in conjunction with a condenser and evaporator to cool the cold trap tube. However, when existing evaporators are used with the cold trap tube, the cooling effect is not ideal, hindering the stable and efficient adsorption and concentration of trace components.

[0004] Therefore, this utility model proposes a device for enriching and analyzing trace components in gas detection. The copper tube for conveying refrigerant is tightly spirally wound into an evaporator, and a heat-conducting round bar is inserted inside the evaporator to cool the cold trap tube. The process is efficient and stable, bringing convenience to the detection of trace components in gas. Utility Model Content

[0005] The purpose of this invention is to address the shortcomings of the prior art by providing a device for enriching and analyzing trace components in gas detection, thereby achieving more stable and efficient concentration of trace components in gas.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a device for enriching and analyzing trace components in gas detection, comprising a compressor, a condenser, a drying filter, and an electronic expansion valve. The compressor outlet is connected to a copper tube, which is connected in sequence to the drying filter, the electronic expansion valve, and the evaporator via the condenser. The evaporator is made of tightly spirally wound copper tube, and the evaporator is connected to the compressor inlet to form a loop. The evaporator is hollow, and a heat-conducting rod is provided inside the evaporator. A through hole is provided in the heat-conducting rod, and a cold trap tube is provided in the through hole.

[0007] Furthermore, a heating power source is applied to both ends of the cold trap tube.

[0008] Furthermore, the heating power supply includes a transformer that converts 220V AC power into 4V 30A AC power and applies it to both ends of the cold trap tube through wires.

[0009] Furthermore, a temperature sensor is fixedly installed on the cold trap tube, and the temperature sensor is connected to the control motherboard and the control switch of the heating power supply of the control motherboard.

[0010] Furthermore, the heat-conducting round rod is provided with retaining rings at both ends, and the retaining rings are threadedly connected to the outer wall of the heat-conducting round rod. The retaining rings on both sides cooperate with the evaporator to fix the heat-conducting round rod.

[0011] Furthermore, the cold trap tube is detachably and fixedly installed in the through hole.

[0012] Furthermore, an annular groove is provided around the outer periphery of the cold trap tube; an installation groove is provided on the heat-conducting round rod, and two installation posts are provided in the installation groove. A connecting plate is slidably sleeved on the installation posts, and a cover plate is fixedly provided above the installation posts. A spring is compressed between the cover plate and the connecting plate and is sleeved on the installation posts; a clamping head is provided below the connecting plate. The front end of the clamping head is hemispherical, and part or all of the hemispherical front end of the clamping head extends into the through hole and fits tightly with the annular groove.

[0013] Furthermore, the evaporator is externally covered with an insulation layer.

[0014] The beneficial effects of this utility model are:

[0015] 1. The overall structure of this utility model is simpler, easier to assemble, and more convenient to use;

[0016] 2. This invention can achieve efficient cooling of the cold trap tube, which is conducive to the low-temperature enrichment of trace components. The process is efficient and stable, bringing convenience to the detection of trace components in gas. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0018] Figure 2 This is a utility model Figure 1 A magnified view of part A in the middle;

[0019] Figure 3 This is a schematic diagram of the overall structure of the heat-conducting round bar of this utility model;

[0020] Figure 4 This is a utility model Figure 3 A cross-sectional view of the AA surface;

[0021] Figure 5 This is a utility model Figure 4 A magnified view of part B in the diagram.

[0022] The names corresponding to each mark in the diagram:

[0023] 1. Compressor; 2. Copper pipe; 3. Condenser; 4. Dryer filter; 5. Electronic expansion valve; 6. Evaporator; 7. Heat transfer rod; 71. Retaining ring; 72. Through hole; 73. Mounting groove; 74. Mounting column; 75. Connecting plate; 76. Cover plate; 77. Spring; 78. Clip; 8. Cold trap tube; 81. Annular groove; 9. Heating power supply; 91. Wire. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model are within the protection scope of the present utility model.

[0025] Embodiments of this utility model:

[0026] like Figure 1-5 As shown, the enrichment and analysis device in this embodiment includes a compressor 1. The refrigerant (high temperature and high pressure gaseous state) output by the compressor 1 is connected to the condenser 3, the dryer filter 4, the electronic expansion valve 5 and the evaporator 6 in sequence through the copper pipe 2. Then the refrigerant in the copper pipe 2 returns to the compressor 1 to form a cycle.

[0027] The evaporator 6 is made of tightly spirally wound copper tube 2. A heat conduction rod 7 is inserted into the evaporator 6. The heat conduction rod 7 is in contact with the inner wall of the evaporator 6. A retaining ring 71 is provided at both ends of the heat conduction rod 7. The retaining rings 71 on both sides are threadedly connected to the outer wall 7 of the heat conduction rod and cooperate with each other to fix the heat conduction rod 7 in the evaporator 6.

[0028] The heat-conducting round rod 7 has through holes 72 extending through both ends. A cold trap tube 8 is inserted through the through holes 72 and filled with adsorbent packing material. The heat-conducting round rod 7 has an installation groove 73 with two installation posts 74 in it. A connecting plate 75 is slidably fitted onto the two installation posts 74. The upper parts of the two installation posts 74 are connected to a cover plate 76 by screws. Two springs 77 are provided between the cover plate 76 and the connecting plate 75 and are respectively fitted onto the installation posts 74. A clamp 78 is connected to the lower part of the connecting plate 75. The front end of the clamp 78 is hemispherical and extends into the through hole 72. An annular groove 81 is provided on the wall of the cold trap tube 8. The front end of the clamp 78 mates with the annular groove 81.

[0029] The cold trap tube 8 is connected to the heating power supply 9 at both ends. The heating power supply 9 includes a transformer that converts 220V AC power into 4V 30A AC power and applies it to the two ends of the cold trap tube 8 through wires 91. A temperature sensor is fixedly installed on the cold trap and is connected to the control main board. The control main board is connected to the control switch of the heating power supply 9.

[0030] The principle of this utility model is as follows:

[0031] The adsorption packing is filled in the cold trap tube 8. The adsorption packing is a mature existing technology. Taking the detection of trace sulfides in gas as an example, it is widely used in existing sulfide concentrators (such as SC-4223), including molecular sieves, etc. This utility model does not make any improvement to the packing itself, so it will not be described in detail.

[0032] In this invention, copper tube 2 is tightly spirally wound to form a hollow evaporator 6. The high-pressure, low-temperature refrigerant, passing through the condenser 3 (where a fan removes heat), is converted to a low-temperature, low-pressure refrigerant via electronic expansion valve 5. This refrigerant then undergoes a change from liquid to gaseous state within the evaporator 6, absorbing heat and lowering the temperature inside and around the evaporator 6. The cold trap tube 8 is located within the heat-conducting rod 7 inside the evaporator 6. The heat from the gas introduced into the cold trap tube 8 is conducted through the heat-conducting rod 7 and then absorbed by the refrigerant, thus cooling the introduced gas. As the gas temperature decreases, trace amounts of sulfide gas in the gas are adsorbed into the cold trap tube 8, completing the enrichment process of trace sulfides. In this invention, the cold trap tube 8 is made of stainless steel, and an annular groove 81 is provided on its outer wall. The heat conduction rod 7 can be made of copper, which can ensure good heat conduction effect. In the implementation of this invention, a heat insulation layer can be selectively wrapped around the copper tube 2 between the rear end of the condenser 3 and the front end of the evaporator 6 and the outside of the evaporator 6 to reduce heat exchange with the environment, ensure cooling effect and save energy.

[0033] To ensure the stability of the assembly of the heat conduction rod 7 and the cold trap tube 8, retaining rings 71 are threaded to both ends of the heat conduction rod 7. Tightening the retaining rings 71 makes the heat conduction rod 7 stably fixed in the evaporator 6. During the insertion of the cold trap tube 8, when one end of the cold trap tube 8 contacts the clamp 78, the front end of the clamp 78 is hemispherical and extends into the through hole 72 (it should not extend too far to avoid the clamp not being able to be pushed back under external force). At the same time, a spring 77 (in a compressed state) is set between the upper connecting plate 75 and the cover plate 76. Therefore, under the action of thrust, the clamp 78 will be pressed upward. When the annular groove 81 on the outer wall of the cold trap tube 8 cooperates with the clamp 78, the cold trap tube 8 can be fixed in the heat conduction rod 7. When it is necessary to remove the cold trap tube 8, simply push the cold trap tube 8 out.

[0034] The gas enriched by low-temperature adsorption needs to be desorbed during detection. By applying current to the cold trap tube 8, the cold trap tube 8 can be directly heated. The temperature sensor is used for temperature control. The adsorbed sulfide gas is desorbed and then used for detection. Since the sulfide is enriched, the detection process of trace sulfides is realized.

[0035] This utility model also involves compressor 1, condenser 3, electronic expansion valve 5, dryer filter 4, transformer, temperature sensor, etc. Since these are existing mature components, they are not difficult for those skilled in the art to understand, and their structural principles will not be described in detail.

Claims

1. A device for enriching and analyzing trace components in gas detection, comprising a compressor (1), a condenser (3), a drying filter (4), and an electronic expansion valve (5), characterized in that: The compressor (1) outlet is connected to the copper pipe (2), and the copper pipe (2) is connected to the dryer filter (4), the electronic expansion valve (5) and the evaporator (6) in sequence via the condenser (3). The evaporator (6) is made of copper pipe (2) tightly spirally wound. The evaporator (6) is connected to the compressor (1) inlet to form a circulation. The evaporator (6) is hollow. A heat conduction rod (7) is provided in the evaporator (6). A through hole (72) is provided in the heat conduction rod (7) with both ends connected. A cold trap tube (8) is provided in the through hole (72).

2. The device for enrichment and analysis of trace components in gas detection according to claim 1, characterized in that: Heating power (9) is applied to both ends of the cold trap tube (8).

3. The device for enrichment and analysis of trace components in gas detection according to claim 2, characterized in that: The heating power supply (9) includes a transformer that converts 220V AC power into 4V 30A AC power and applies it to both ends of the cold trap tube (8) through wires (91).

4. The device for enrichment and analysis of trace components in gas detection according to claim 2, characterized in that: A temperature sensor is fixedly installed on the cold trap tube (8), and the temperature sensor is connected to the control motherboard and the control switch of the heating power supply (9) of the control motherboard.

5. The apparatus for enrichment and analysis of trace components in gas detection according to claim 1, characterized in that: The heat-conducting round rod (7) is provided with retaining rings (71) at both ends. The retaining rings (71) are threaded to the outer wall of the heat-conducting round rod (7). The retaining rings (71) on both sides cooperate with the evaporator (6) to fix the heat-conducting round rod (7).

6. The apparatus for enrichment and analysis of trace components in gas detection according to claim 1, characterized in that: The cold trap tube (8) is detachably fixed in the through hole (72).

7. The apparatus for enrichment and analysis of trace components in gas detection according to claim 6, characterized in that: The cold trap tube (8) has an annular groove (81) around its outer periphery; an installation groove (73) is provided on the heat conduction rod (7), and two installation posts (74) are provided in the installation groove (73). A connecting plate (75) is slidably sleeved on the installation posts (74). A cover plate (76) is fixedly provided above the installation posts (74). A spring (77) is compressed between the cover plate (76) and the connecting plate (75), and the spring (77) is sleeved on the installation posts (74); a clamp (78) is provided below the connecting plate (75). The front end of the clamp (78) is hemispherical, and part or all of the hemispherical front end of the clamp (78) extends into the through hole (72) and fits tightly with the annular groove (81).

8. The apparatus for enrichment and analysis of trace components in gas detection according to claim 1, characterized in that: The evaporator (6) is covered with an insulation layer.

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