Device and method for preparing trace moisture standard gas

Abstract

The invention discloses a trace moisture standard gas preparation device and method, and relates to the technical field of standard gas. The device comprises: a high-purity gas source; the flow control module is connected with the high-purity gas source and used for controlling the flow of the high-purity gas source; the permeation system comprises a sealing cavity, a permeation pipe and a thermostat, distilled water is contained in the sealing cavity and heated through the thermostat, and the permeation pipe is arranged in the sealing cavity; the high-purity gas enters the permeation pipe through the flow control module and the connecting pipeline and is fully mixed with water permeating into the permeation pipe to form trace water standard gas, and the invention further provides a preparation method of the trace water standard gas based on the device. The device realizes the preparation of the trace moisture standard gas, and has the advantages of simple structure, convenience in operation, low cost, short production preparation period, high stability and accurate concentration of the trace moisture standard gas, and can be used for quickly preparing a large amount of the trace moisture standard gas.

Description

Technical Field

[0001] The present invention relates to the technical field of standard gases, and in particular to a device and method for preparing trace moisture standard gas. Background Art

[0002] With the rapid development of commerce and science and technology, the demand for standard gases has increased dramatically, and they are widely used in the fields of oil and gas development, chemical production, environmental monitoring, scientific research, etc. In industrial production, standard gases are used to calibrate and detect analytical instruments, and can also be used to monitor and adjust the concentration during the production of standard gases; in scientific research experiments, standard gases are used for benchmark calibration, material detection and quantitative analysis, etc.

[0003] In the preparation method of trace moisture standard gas, the dual pressure method has the disadvantages of complex equipment, difficult operation and maintenance, high cost and high energy consumption. The weighing method also has the disadvantages of many operating steps, time-consuming preparation process, long stabilization period and high cost. Therefore, a device and method for preparing trace moisture standard gas with simple operation, more economical cost and rapid large-scale preparation is provided. Summary of the invention

[0004] The present invention aims to solve the technical problems of complex operation, high cost and high energy consumption in the prior art of preparing trace moisture standard gas. The present invention aims to provide a device and method for preparing trace moisture standard gas, which realizes the preparation of trace moisture standard gas. The device has a simple structure, convenient operation, economical cost and short production preparation cycle. It can quickly prepare trace moisture standard gas in large quantities, has high stability and accurate standard gas concentration.

[0005] The present invention is achieved through the following technical solutions:

[0006] The first object of the present invention is to provide a trace moisture standard gas preparation device, comprising:

[0007] High purity gas source;

[0008] A flow control module, connected to a high-purity gas source, for controlling the flow of the high-purity gas source;

[0009] The permeation system comprises a sealed cavity, a permeation tube and a thermostat, wherein the sealed cavity is filled with distilled water and heated by the thermostat, and the permeation tube is arranged inside the sealed cavity;

[0010] The high-purity gas enters the permeation tube through the flow control module and the connecting pipeline, and is fully mixed with the moisture that has permeated into the permeation tube to form a trace moisture standard gas.

[0011] Furthermore, the high-purity gas source is nitrogen, helium or argon.

[0012] Furthermore, an air inlet and an air outlet are provided on the top of the sealed cavity, and both ends of the permeation tube are connected to the air inlet and the air outlet respectively.

[0013] Furthermore, the permeation tubes are arranged in a serpentine shape inside the sealed cavity.

[0014] Furthermore, a heat-insulating layer is arranged outside the sealed cavity.

[0015] Furthermore, the thermostat is arranged at the bottom of the sealed cavity, and the thermostat comprises a temperature sensor and a heater, which are used to heat and stabilize the temperature in the sealed cavity.

[0016] Furthermore, it also includes a moisture detection device, which is connected to the outlet of the infiltration system.

[0017] The second object of the present invention is to provide a method for preparing a trace moisture standard gas, which is based on the above-mentioned device and comprises the following steps:

[0018] The flow rate of the high-purity gas is controlled by a flow control module, and the high-purity gas is passed into the permeation tube of the permeation system;

[0019] The distilled water in the sealed chamber is heated, and the water penetrates into the permeation tube and is fully mixed with the high-purity gas to obtain trace moisture standard gas.

[0020] Furthermore, it also includes:

[0021] The obtained trace moisture standard gas is tested by a moisture detection device, and the prepared trace moisture standard gas is collected and stored after meeting the requirements.

[0022] Furthermore, the flow rate range of the high-purity gas is 0.3-10 L / min, the relative pressure in the sealed cavity is 0-0.5 MPa, and the temperature range in the sealed cavity is 0-99° C.

[0023] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0024] 1. The present invention realizes the preparation of trace moisture standard gas by sequentially connecting a high-purity gas source, a flow control module and a permeation system. The device has a simple structure, convenient operation, economical cost, and a short production preparation cycle. It can quickly prepare a large amount of trace moisture standard gas with high stability and accurate standard gas concentration.

[0025] 2. The infiltration system of the present invention effectively avoids the influence of external interference factors on the water permeability by setting up a sealed chamber and provides a stable pressure environment. By setting a thermostat to stabilize the temperature in the sealed chamber, the fluctuation of ambient temperature is avoided from interfering with the water permeability. At the same time, the permeation tube made of polymer composite materials is used to make the permeation more stable. Therefore, based on these structural designs, the influence of various factors on the water permeability can be effectively avoided, thereby ensuring the stability of water penetrating into the permeation tube and improving the stability of the device in preparing trace moisture standard gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0027] Figure 1 It is a schematic diagram of the structure of the device of the present invention.

[0028] Marks and corresponding parts names in the attached drawings:

[0029] 1-high purity gas source, 2-connecting pipeline, 3-flow control module, 4-permeation system, 5-moisture detection device, 6-finished product container, 41-air inlet, 42-air outlet, 43-permeation tube, 44-sealed cavity, 45-insulation layer, 46-thermostat, 461-temperature sensor, 462-heater. DETAILED DESCRIPTION

[0030] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the technical solutions in the embodiments of the present invention are clearly and completely described below in combination with the embodiments and drawings. Obviously, the schematic implementation modes of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0031] The following is a detailed description of the embodiment of a trace moisture standard gas preparation device and method of the present invention with appropriate reference to the accompanying drawings. However, there may be cases where unnecessary detailed descriptions are omitted. For example, there are cases where detailed descriptions and repeated descriptions of well-known matters are omitted. This is to avoid the following description from becoming unnecessarily lengthy and facilitate the understanding of those skilled in the art.

[0032] The "range" disclosed in this application is defined in the form of a lower limit and an upper limit, and a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of the particular range. The range defined in this way can be inclusive or exclusive of the end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a range.

[0033] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0034] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form a new technical solution.

[0035] Unless otherwise specified, the terms "include" and "comprising" mentioned in this application may be open-ended or closed-ended. For example, the terms "include" and "comprising" may mean that other substances not listed may also be included or only the listed substances may be included.

[0036] If there is no special explanation, all the steps of the present application can be performed sequentially or randomly, preferably sequentially.

[0037] The technical solution of the present invention is further described in detail below in conjunction with embodiments.

[0038] Example 1

[0039] A device for preparing a trace moisture standard gas, such as Figure 1 As shown, including:

[0040] High purity gas source 1;

[0041] A flow control module 3, connected to the high-purity gas source 1 via a connecting pipeline 2, and used to control the flow of the high-purity gas source 1;

[0042] The permeation system 4 comprises a sealed chamber 44, a permeation tube 43 and a thermostat 46. The sealed chamber 44 is filled with distilled water and heated by the thermostat 46. The permeation tube 43 is arranged inside the sealed chamber 44.

[0043] The high-purity gas enters the permeation tube 43 through the flow control module 3 and the connecting pipeline 2, and is fully mixed with the moisture that has permeated into the permeation tube 43 to form a trace moisture standard gas.

[0044] The present invention realizes the preparation of trace moisture standard gas by sequentially connecting a high-purity gas source 1, a flow control module 3 and a permeation system 4. The device has a simple structure, convenient operation, economical cost, and a short production preparation cycle. It can quickly prepare a large amount of trace moisture standard gas with high stability and accurate standard gas concentration.

[0045] The infiltration system 4 of the present invention effectively avoids the influence of external interference factors on the water permeability by setting up a sealed chamber 44, and provides a stable pressure environment. By setting a thermostat 46 for stabilizing the temperature in the sealed chamber 44, the fluctuation of ambient temperature is avoided from interfering with the water permeability. At the same time, the permeation tube 43 made of polymer composite materials is adopted to make the permeation more stable. Therefore, based on these structural designs, the influence of various factors on the water permeability can be effectively avoided, thereby ensuring the stability of the water infiltrated into the permeation tube 43 and improving the stability of the device in preparing trace moisture standard gas.

[0046] As a further technical solution of the present invention, the high-purity gas source 1 is usually an inert gas, such as nitrogen, helium or argon.

[0047] As a further technical solution of the present invention, an air inlet 41 and an air outlet 42 are provided at the top of the sealed cavity 44. The air inlet 41 at the top of the sealed cavity 44 is connected to the flow control module 3 through a pipeline, and both ends of the permeation tube 43 are respectively connected to the air inlet 41 and the air outlet 42. The air inlet 41 and the air outlet 42 facilitate the connection of both ends of the permeation tube 43 with the connecting pipeline 2 to achieve the introduction of high-purity gas.

[0048] As a further technical solution of the present invention, a heat-insulating layer 45 is disposed outside the sealed cavity 44 , and the heat-insulating layer 45 is used to stabilize the temperature inside the sealed cavity 44 , further preventing fluctuations in ambient temperature from interfering with the water permeability.

[0049] As a further technical solution of the present invention, the permeation tube 43 is arranged in a serpentine shape inside the sealed cavity 44. By arranging the permeation tube 43 in a serpentine shape, the moisture and the high-purity gas can be mixed more fully and evenly, thereby improving the quality of the prepared trace moisture standard gas.

[0050] As a further technical solution of the present invention, the thermostat 46 is arranged at the bottom of the sealed cavity 44. The thermostat 46 includes a temperature sensor 461 and a heater 462, which are used to heat and stabilize the temperature in the sealed cavity 44. The temperature sensor 461 can detect temperature changes in real time and transmit signals to the heater 462. The heater 462 automatically adjusts the heating temperature according to the temperature changes, thereby ensuring that the temperature in the sealed cavity 44 is always maintained at a stable level, avoiding fluctuations in ambient temperature from interfering with the permeability of moisture.

[0051] As a further technical solution of the present invention, it also includes a moisture detection device 5, which is connected to the gas outlet 42 of the infiltration system 4 through the connecting pipeline 2. The present invention precisely controls the flow rate and temperature by setting the flow control module 3 and the thermostat 46, and detects and calibrates the trace moisture standard gas through the moisture detection device 5, so as to ensure the preparation and production of the trace moisture standard gas within a certain concentration range, and ensure stable performance; the qualified trace moisture standard gas is passed into the finished product container 6 for storage or directly passed into the user device for use.

[0052] It should be noted that the connections between the connecting pipeline 2 and the high-purity gas source 1, the connecting pipeline 2 and the flow control module 3, the connection and the permeation system 4, the connection and the moisture detection device 5, and the connection and the finished product container 6 are all sealed, which can effectively avoid the influence of external interference factors.

[0053] Example 2

[0054] This example is a method for preparing a standard gas of trace moisture in nitrogen, which is carried out based on the apparatus of Example 1.

[0055] A method for preparing a trace moisture standard gas comprises the following steps:

[0056] S1. Use liquid nitrogen with a water content of less than 0.05ppm or purified high-purity nitrogen as the high-purity gas source 1, maintain the output pressure of 0.1MPa through a pressure regulating valve, and control the flow rate of the high-purity gas through a flow control module 3. The flow control module 3 uses a mass flow controller to stably output a flow rate of 1L / min through the mass flow controller.

[0057] S2. The distilled water in the sealed chamber 44 is heated by the thermostat 46, and the temperature in the sealed chamber 44 is controlled to be 80°C±0.1°C. The pressure in the sealed chamber 44 is 96Kpa. The high-purity gas is introduced into the permeation tube 43 of the permeation system 4 and flows in the permeation tube 43, and is fully mixed with the water that permeates into the permeation tube 43 to obtain a trace moisture standard gas.

[0058] S3. The trace moisture standard gas is introduced into the moisture detection device 5. The moisture detection device 5 adopts a cold mirror dew point meter. The nitrogen concentration value of a certain water content produced by the test is 12ppm. The standard gas can meet the 0-100ppm trace gas measurement error requirement.

[0059] S4. Collect and store the prepared trace moisture standard gas, and the obtained nitrogen gas with a certain water content can be used as a standard gas for calibrating the dew point instrument.

[0060] Example 3

[0061] The difference between this embodiment and embodiment 2 is that the temperature in the sealed cavity 44 is controlled to be 0°C±0.1°C. The specific preparation method is as follows:

[0062] S1. Use liquid nitrogen with a water content of less than 0.05ppm or purified high-purity nitrogen as the high-purity gas source 1, maintain the output pressure of 0.1MPa through a pressure regulating valve, and control the flow rate of the high-purity gas through a flow control module 3. The flow control module 3 uses a mass flow controller to stably output a flow rate of 1L / min through the mass flow controller.

[0063] S2. The distilled water in the sealed chamber 44 is heated by the thermostat 46, and the temperature in the sealed chamber 44 is controlled to be 0°C±0.1°C. The pressure in the sealed chamber 44 is 96Kpa. The high-purity gas is introduced into the permeation tube 43 of the permeation system 4 and flows in the permeation tube 43, and is fully mixed with the water that permeates into the permeation tube 43 to obtain a trace moisture standard gas.

[0064] S3. The trace moisture standard gas is introduced into the moisture detection device 5. The moisture detection device 5 adopts a cold mirror dew point meter. The nitrogen concentration value of a certain water content produced by the test is 0.2ppm. The standard gas can meet the 0-100ppm trace gas measurement error requirement.

[0065] S4. Collect and store the prepared trace moisture standard gas, and the obtained nitrogen gas with a certain water content can be used as a standard gas for calibrating the dew point instrument.

[0066] Example 4

[0067] The difference between this embodiment and embodiment 2 is that the temperature in the sealed cavity 44 is controlled to be 99°C ± 0.1°C. The specific preparation method is as follows:

[0068] S1. Use liquid nitrogen with a water content of less than 0.05ppm or purified high-purity nitrogen as the high-purity gas source 1, maintain the output pressure of 0.1MPa through a pressure regulating valve, and control the flow rate of the high-purity gas through a flow control module 3. The flow control module 3 uses a mass flow controller to stably output a flow rate of 1L / min through the mass flow controller.

[0069] S2. The distilled water in the sealed chamber 44 is heated by the thermostat 46, and the temperature in the sealed chamber 44 is controlled to be 99°C±0.1°C. The pressure in the sealed chamber 44 is 96Kpa. The high-purity gas is introduced into the permeation tube 43 of the permeation system 4 and flows in the permeation tube 43, and is fully mixed with the water that permeates into the permeation tube 43 to obtain a trace moisture standard gas.

[0070] S3. The trace moisture standard gas is introduced into the moisture detection device 5. The moisture detection device 5 adopts a cold mirror dew point meter. The nitrogen concentration value of a certain water content produced by the test is 42ppm. The standard gas can meet the 0-100ppm trace gas measurement error requirement.

[0071] S4. Collect and store the prepared trace moisture standard gas, and the obtained nitrogen gas with a certain water content can be used as a standard gas for calibrating the dew point instrument.

[0072] Example 5

[0073] The difference between this embodiment and embodiment 2 is that the flow control module 3 controls the output flow rate to be 5 L / min. The specific preparation method is as follows:

[0074] S1. Use liquid nitrogen with a water content of less than 0.05ppm or purified high-purity nitrogen as the high-purity gas source 1, maintain the output pressure of 0.1MPa through a pressure regulating valve, and control the flow rate of the high-purity gas through a flow control module 3. The flow control module 3 uses a mass flow controller to stably output a flow rate of 5L / min through the mass flow controller.

[0075] S2. The distilled water in the sealed chamber 44 is heated by the thermostat 46, and the temperature in the sealed chamber 44 is controlled to be 80°C±0.1°C. The pressure in the sealed chamber 44 is 96Kpa. The high-purity gas is introduced into the permeation tube 43 of the permeation system 4 and flows in the permeation tube 43, and is fully mixed with the water that permeates into the permeation tube 43 to obtain a trace moisture standard gas.

[0076] S3. The trace moisture standard gas is introduced into the moisture detection device 5. The moisture detection device 5 adopts a cold mirror dew point meter. The nitrogen concentration value of a certain water content produced by the test is 10ppm. The standard gas can meet the 0-100ppm trace gas measurement error requirement.

[0077] S4. Collect and store the prepared trace moisture standard gas, and the obtained nitrogen gas with a certain water content can be used as a standard gas for calibrating the dew point instrument.

[0078] Example 6

[0079] The difference between this embodiment and embodiment 2 is that the flow control module 3 controls the output flow rate to be 10 L / min. The specific preparation method is as follows:

[0080] S1. Use liquid nitrogen with a water content of less than 0.05ppm or purified high-purity nitrogen as the high-purity gas source 1, maintain the output pressure of 0.1MPa through a pressure regulating valve, and control the flow rate of the high-purity gas through a flow control module 3. The flow control module 3 uses a mass flow controller to stably output a flow rate of 10L / min through the mass flow controller.

[0081] S2. The distilled water in the sealed chamber 44 is heated by the thermostat 46, and the temperature in the sealed chamber 44 is controlled to be 80°C±0.1°C. The pressure in the sealed chamber 44 is 96Kpa. The high-purity gas is introduced into the permeation tube 43 of the permeation system 4 and flows in the permeation tube 43, and is fully mixed with the water that permeates into the permeation tube 43 to obtain a trace moisture standard gas.

[0082] S3. The trace moisture standard gas is introduced into the moisture detection device 5. The moisture detection device 5 adopts a cold mirror dew point meter. The nitrogen concentration value of a certain water content produced by the test is 8ppm. The standard gas can meet the 0-100ppm trace gas measurement error requirement.

[0083] S4. Collect and store the prepared trace moisture standard gas, and the obtained nitrogen gas with a certain water content can be used as a standard gas for calibrating the dew point instrument.

[0084] In summary, the output concentration range of the trace moisture standard gas of the present invention can be controlled by temperature adjustment, and the temperature adjustment range is 0-99°C, realizing the preparation of standard gas in the range of 0.2-42ppm (fluctuation range: ±0.05ppm), which can meet the error requirements of trace gas determination of 0-100ppm.

[0085] Finally, it should be noted that the above specific embodiments are only used to explain in detail the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific implementation method of the present invention and is not used to limit the protection scope of the present invention. Although the present invention is described in detail with reference to the above specific embodiments, ordinary technicians in this field should understand that it is still possible to modify the technical solutions recorded in the above embodiments, or to replace or improve some or all of the technical features therein. These modifications, equivalent replacements and improvements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and description of the present invention.

Claims

1. A device for preparing a trace moisture standard gas, characterized in that: include: High purity gas source (1); A flow control module (3), connected to the high-purity gas source (1) and used to control the flow of the high-purity gas source (1); The permeation system (4) comprises a sealed chamber (44), a permeation tube (43) and a thermostat (46), wherein the sealed chamber (44) is filled with distilled water and heated by the thermostat (46), and the permeation tube (43) is arranged inside the sealed chamber (44); The high-purity gas enters the permeation tube (43) through the flow control module (3) and the connecting pipeline (2), and is fully mixed with the moisture that has permeated into the permeation tube (43) to form a trace moisture standard gas.

2. A trace moisture standard gas preparation device according to claim 1, characterized in that: The high-purity gas source (1) is nitrogen, helium or argon.

3. A trace moisture standard gas preparation device according to claim 1, characterized in that: An air inlet (41) and an air outlet (42) are provided at the top of the sealed cavity (44), and two ends of the permeation tube (43) are respectively connected to the air inlet (41) and the air outlet (42).

4. A trace moisture standard gas preparation device according to claim 1, characterized in that: The permeation tube (43) is arranged in a serpentine shape inside the sealed cavity (44).

5. The device for preparing a trace moisture standard gas according to claim 1, characterized in that: A thermal insulation layer (45) is arranged outside the sealed cavity (44).

6. The device for preparing a trace moisture standard gas according to claim 1, characterized in that: The thermostat (46) is arranged at the bottom of the sealed cavity (44), and comprises a temperature sensor (461) and a heater (462), and is used to heat and stabilize the temperature in the sealed cavity (44).

7. The device for preparing a trace moisture standard gas according to claim 1, characterized in that: It also comprises a moisture detection device (5), wherein the moisture detection device (5) is connected to the outlet of the infiltration system (4).

8. A method for preparing a trace moisture standard gas, characterized in that: Based on the device according to any one of claims 1 to 7, the method comprises the following steps: The flow rate of the high-purity gas is controlled by a flow control module (3), and the high-purity gas is passed into a permeation tube (43) of a permeation system (4); The distilled water in the sealed cavity (44) is heated, and the water penetrates into the inside of the permeation tube (43) and is fully mixed with the high-purity gas to obtain a trace water standard gas.

9. The method for preparing a trace moisture standard gas according to claim 8, characterized in that: Also includes: The obtained trace moisture standard gas is tested by a moisture detection device (5), and the prepared trace moisture standard gas is collected and stored after meeting the requirements.

10. The method for preparing a trace moisture standard gas according to claim 8, characterized in that: The flow rate range of the high-purity gas is 0.3-10 L / min, the relative pressure in the sealed cavity (44) is 0-0.5 MPa, and the temperature range in the sealed cavity (44) is 0-99° C.

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