Gas sampling device based on liquid absorption technology

Abstract

The utility model provides a gas sampling device based on a liquid absorption technology, which comprises an absorption pipeline provided with a gas inlet, a liquid inlet and a liquid outlet; the first container is provided with a medium inlet and a medium outlet, and the absorption pipeline is located in the first container; the first pipeline communicates with the medium inlet; the second pipeline communicates with the medium outlet; the second container is lower than the first container; the flow path switching module is arranged on the first pipeline and the second pipeline and used for enabling the medium inlet to selectively communicate with the other end of the first pipeline or the first outlet and enabling the medium outlet to selectively communicate with the other end of the second pipeline or the second outlet. The positions of the first outlet and the second outlet are higher than the liquid level; the pump is arranged on the first pipeline and located on the upstream of the flow path switching module. Or the flow path switching module is arranged on the second pipeline and is positioned at the downstream of the flow path switching module. The utility model has the advantages of good reliability and the like.

Description

Technical Field

[0001] The utility model relates to gas sampling, in particular to a gas sampling device based on liquid absorption technology. Background Art

[0002] In the field of environmental monitoring, due to the high activity and short life of certain atmospheric pollutants (such as atmospheric nitrite), wet chemical methods are often used to absorb the sample gas into a stable liquid using an absorption liquid for further analysis and detection.

[0003] In order to improve the accuracy of sampling, in-situ sampling is usually adopted. The sampling port is placed outdoors, and the absorption liquid is transported to the outdoor sampling device to make the sample gas and the absorption liquid contact quickly to prevent the sample gas state from changing. At the same time, in order to ensure the stability of gas-liquid conversion, the sampling device (i.e. the gas-liquid conversion site) is often temperature-controlled. The water bath constant temperature device is the most commonly used and simplest temperature control method. It has the advantages of uniform heating and smooth process, avoiding excessive intensity and uncontrollable temperature caused by direct heating, but it also has the following risks:

[0004] When the power is unexpectedly cut off in winter, the water in the pipe cannot automatically flow back. The outdoor temperature is low, and the water stored in the pipe and the water bath insulation layer is very easy to freeze. As a result, when the power is turned on again, the circulating water cannot be turned on normally, and the constant temperature sampling device cannot be used normally. Even in the case of long-term freezing, the volume increases compared to before, which can easily cause the pipe and the water bath insulation layer to freeze and crack, thereby causing irreversible damage to the sampling device. Summary of the invention

[0005] In order to solve the deficiencies in the above-mentioned prior art solutions, the utility model provides a gas sampling device based on liquid absorption technology.

[0006] The purpose of this utility model is achieved through the following technical solutions:

[0007] A gas sampling device based on liquid absorption technology comprises an absorption pipeline, wherein the absorption pipeline has a gas inlet, a liquid inlet and a liquid outlet; the gas sampling device based on liquid absorption technology further comprises:

[0008] A first container, wherein the first container has a medium inlet and a medium outlet, and the absorption pipeline is located in the first container;

[0009] a first pipeline and a second pipeline, wherein one end of the first pipeline is connected to the medium inlet, and one end of the second pipeline is connected to the medium outlet;

[0010] a second container, wherein the second container is located lower than the first container; the other end of the first pipe and the other end of the second pipe are respectively below the liquid level in the second container;

[0011] a flow path switching module, the flow path switching module being arranged on the first pipeline and the second pipeline, and being used to selectively connect the medium inlet to the other end or the first outlet of the first pipeline, and selectively connect the medium outlet to the other end or the second outlet of the second pipeline, respectively, wherein the first outlet and the second outlet are located above the liquid surface;

[0012] A pump is disposed on the first pipeline and upstream of the flow path switching module; or, the pump is disposed on the second pipeline and downstream of the flow path switching module.

[0013] Compared with the prior art, the utility model has the following beneficial effects:

[0014] 1. Good job stability;

[0015] By setting the flow path switching module and the pump position, the gas sampling device has an automatic reflux function when power is off, so that when an unexpected power outage occurs, the medium in the first pipeline, the second pipeline and the interlayer (between the absorption pipeline and the first container) slowly and automatically flows back to the second container, which not only avoids water resource waste, but also avoids the freezing and cracking of the pipeline or the malfunction of the power-on device due to water freezing when an unexpected power outage occurs in winter, thereby improving the working stability and adaptability;

[0016] 2. Simple structure and automation;

[0017] Components such as flow path switching modules and pumps are all conventional components with simple structure and good reliability;

[0018] The flow path switching module adopts a three-way solenoid valve to realize automatic operation and realize automatic reflux function without human intervention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The disclosure of the present invention will become easier to understand with reference to the accompanying drawings. It is easy for those skilled in the art to understand that these drawings are only used to illustrate the technical solution of the present invention and are not intended to limit the scope of protection of the present invention. In the drawings:

[0020] Figure 1 It is a simplified structural diagram of a gas sampling device based on liquid absorption technology according to an embodiment of the utility model. DETAILED DESCRIPTION

[0021] Figure 1The following description describes optional specific embodiments of the present invention to teach those skilled in the art how to implement and reproduce the present invention. In order to teach the technical solution of the present invention, some conventional aspects have been simplified or omitted. Those skilled in the art should understand that variations or substitutions derived from these specific embodiments will be within the scope of the present invention. Those skilled in the art should understand that the following features can be combined in various ways to form multiple variations of the present invention. Thus, the present invention is not limited to the following optional specific embodiments, but is only limited by the claims and their equivalents.

[0022] Example 1

[0023] The gas sampling device based on liquid absorption technology in Example 1 of the utility model is as follows: Figure 1 As shown, the gas sampling device based on liquid absorption technology includes:

[0024] An absorption pipeline 15, wherein the absorption pipeline 15 has a gas inlet 12, a liquid inlet 13 and a liquid outlet 14;

[0025] A first container 11, wherein the first container 11 has a medium inlet 18 and a medium outlet 17, the absorption pipeline 11 is located in the first container 11, and the gas inlet 12, the liquid inlet 13 and the liquid outlet 14 extend to the outside of the first container 11;

[0026] A first pipe 31 and a second pipe 32, wherein one end of the first pipe 31 is connected to the medium inlet 18, and one end of the second pipe 32 is connected to the medium outlet 17;

[0027] A second container 21, wherein the second container 21 is located lower than the first container 11; the other ends of the first pipe 31 and the other ends of the second pipe 32 are respectively located below the liquid level in the second container 21;

[0028] a flow path switching module, which is disposed on the first pipe 31 and the second pipe 32, and is used to selectively connect the medium inlet 18 to the other end of the first pipe 31 or the first outlet 24, and selectively connect the medium outlet to the other end of the second pipe 32 or the second outlet 25, respectively. The first outlet 24 and the second outlet 25 are located above the liquid surface;

[0029] A pump is disposed on the first pipeline 31 and upstream of the flow path switching module; or, the pump is disposed on the second pipeline 32 and downstream of the flow path switching module.

[0030] In order to realize the automatic backflow function when power is off, the flow path switching module further includes three-way solenoid valves respectively arranged on the first pipeline 31 and the second pipeline 32. The three-way solenoid valve is used to make the medium inlet 18 connected to the other end of the first pipeline 31 and the medium outlet 17 connected to the other end of the second pipeline 32 when power is on; when power is off, the medium inlet 18 is connected to the first outlet 24, and the medium outlet 17 is connected to the second outlet 25.

[0031] In order to improve the integration, further, the pump is located below the liquid level of the second container 21 .

[0032] In order to prevent the liquid in the pipeline from freezing in cold weather, the gas sampling device further includes:

[0033] The constant temperature module is used to maintain the temperature of the liquid in the second container 21 constant, such as 15-25 degrees.

[0034] In order to improve the constant temperature effect and increase the contact area between the absorption pipe 15 and the interlayer 16, the absorption pipe 15 is further spiral.

[0035] In order to improve the constant temperature capability, further, the outside of the first pipe 31 , the outside of the second pipe 32 and the outside of the first container 11 are all wrapped with a thermal insulation layer.

[0036] Example 2

[0037] An example of application of the gas sampling device based on liquid absorption technology according to Example 1 of the utility model in atmospheric nitrous acid monitoring.

[0038] In this application example, Figure 1 As shown, the absorption pipe 15 and the first container 11 are arranged outdoors, and the second container 21, the first three-way solenoid valve 22 and the second three-way solenoid valve 23 are arranged indoors. The position of the second container 21 is lower than that of the first container 11.

[0039] The absorption pipe 15 is spirally shaped and is disposed in the first container 11. An interlayer 16 is formed between the absorption pipe 15 and the first container 11, and the heat-insulating liquid enters the interlayer 16 through the medium inlet 18 and is discharged from the medium outlet 17. The position of the medium inlet 18 is lower than the position of the medium outlet 17. The gas inlet 12, the liquid inlet 13 and the liquid outlet 14 of the absorption pipe 15 extend to the outside of the first container 11.

[0040] The pump is arranged below the liquid level of the second container 21 and is connected to the bottom end of the first pipe 31. The first three-way solenoid valve 22 is arranged on the first pipe 31 and is above the liquid level, downstream of the pump. When the power is on, the first pipe 31 is kept connected, that is, the pump is connected to the medium inlet 18. When the power is off, the medium inlet 18 is connected to the first outlet 24, the first outlet 24 is above the liquid level, and is connected to the second container 21 through the pipe. The second three-way solenoid valve 23 is arranged on the second pipe 32 and is above the liquid level. When the power is on, the second pipe 32 is kept connected. When the power is off, the medium outlet 17 is connected to the second outlet 25, the second outlet 25 is above the liquid level, and is connected to the second container 21 through the pipe.

[0041] The thermostatic module is used to heat / cool the liquid in the second container 21 and keep the temperature constant, such as maintaining it at 22 degrees. The outside of the first pipe 31, the outside of the second pipe 32 and the outside of the first container 11 are all wrapped with an insulation layer to prevent the liquid in the first pipe 31, the second pipe 32 and the first container 11 from cooling down.

[0042] The working mode of the gas sampling device of this embodiment is:

[0043] During normal operation, air enters the absorption pipe 15 from the gas inlet 12, and the absorption liquid enters the absorption pipe 15 from the liquid inlet 13. Nitrous acid in the air is absorbed by the absorption liquid, discharged from the liquid outlet 14, and sent to the downstream for analysis.

[0044] Under the pump's delivery, the liquid in the second container 21 enters the interlayer 16 through the first three-way solenoid valve 22 and the medium inlet 18 in turn, and then flows back to the second container 21 through the medium outlet 17 and the second three-way solenoid valve 23 in turn, so that the liquid in the absorption pipe 15 maintains a constant temperature.

[0045] When the power is suddenly cut off, the medium inlet 18 is connected to the first outlet 24 of the first three-way solenoid valve 22, and the medium outlet 17 is connected to the second outlet 25 of the second three-way solenoid valve 23, so that the liquid in the interlayer 16 and the first pipeline 31 automatically flows back from the first outlet 24 to the second container 21, and the liquid in the second pipeline 32 automatically flows back from the second outlet 25 to the second container 21.

[0046] Example 3

[0047] The application example of the gas sampling device based on liquid absorption technology in atmospheric nitrous acid monitoring according to Example 1 of the utility model is different from Example 2 in that:

[0048] 1. The three-way valves on the first pipeline 31 and the second pipeline 32 are manual. When the power is off, the staff switches the three-way valves so that the liquid in the interlayer 16, the first pipeline 31 and the second pipeline 32 flows back into the second container 21.

[0049] 2. The position of the medium inlet 18 is higher than the position of the medium outlet 17 .

[0050] When the power is off, the liquid in the interlayer 16 and the second pipe 32 flows back into the second container 21 from the second outlet 25 of the three-way valve, and the liquid in the first pipe 31 flows back into the second container 21 from the first outlet 24 of the three-way valve.

[0051] In the above embodiment, the liquid introduced into the interlayer 16 can be water or other liquids with a large specific heat, thereby ensuring a constant temperature effect of the liquid in the absorption pipe 11 .

Claims

1. A gas sampling device based on liquid absorption technology, comprising an absorption pipeline, wherein the absorption pipeline has a gas inlet, a liquid inlet and a liquid outlet; characterized in that: The gas sampling device based on liquid absorption technology also includes: A first container, wherein the first container has a medium inlet and a medium outlet, and the absorption pipeline is located in the first container; a first pipeline and a second pipeline, wherein one end of the first pipeline is connected to the medium inlet, and one end of the second pipeline is connected to the medium outlet; a second container, wherein the second container is located lower than the first container; the other end of the first pipe and the other end of the second pipe are respectively below the liquid level in the second container; a flow path switching module, the flow path switching module being arranged on the first pipeline and the second pipeline, and being used to selectively connect the medium inlet to the other end or the first outlet of the first pipeline, and selectively connect the medium outlet to the other end or the second outlet of the second pipeline, respectively, wherein the first outlet and the second outlet are located above the liquid surface; A pump is disposed on the first pipeline and upstream of the flow path switching module; or, the pump is disposed on the second pipeline and downstream of the flow path switching module.

2. The gas sampling device based on liquid absorption technology according to claim 1 is characterized in that: The flow path switching module includes three-way solenoid valves respectively arranged on the first pipeline and the second pipeline. The three-way solenoid valve is used to connect the medium inlet to the other end of the first pipeline and the medium outlet to the other end of the second pipeline when power is on, and connect the medium inlet to the first outlet and the medium outlet to the second outlet when power is off.

3. The gas sampling device based on liquid absorption technology according to claim 1 is characterized in that: The pump is below the liquid level.

4. The gas sampling device based on liquid absorption technology according to claim 1 is characterized in that: The first container and the absorption pipe are arranged outdoors, and the second container is arranged indoors.

5. The gas sampling device based on liquid absorption technology according to claim 1 or 4, characterized in that: The gas sampling device also includes: A constant temperature module is used to maintain a constant temperature of the liquid in the second container.

6. The gas sampling device based on liquid absorption technology according to claim 5 is characterized in that: The flow path switching module and the pump are arranged indoors.

7. The gas sampling device based on liquid absorption technology according to claim 1 is characterized in that: The absorption pipeline is spiral.

8. The gas sampling device based on liquid absorption technology according to claim 1 is characterized in that: The outside of the first pipe, the outside of the second pipe and the outside of the first container are all wrapped with a thermal insulation layer.

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