Batch preparation device of gas standard substance

Abstract

The utility model discloses a batch preparation device of a gas standard substance, which belongs to the field of gas standard substance preparation and comprises a vacuum pump, a raw material gas cylinder and a gas cylinder to be filled, the vacuum pump is connected with one end of a main pipeline, and the other end of the main pipeline is connected with one ends of two branch pipelines; the other ends of the two branch pipelines are respectively connected with a raw material gas cylinder and a balancer, the balancer is also connected with one ends of a plurality of to-be-filled pipelines, the other ends of the plurality of to-be-filled pipelines are all connected with a to-be-filled gas cylinder, and the to-be-filled pipelines, the two branch pipelines and the main pipeline are all provided with pipeline valves; a raw material gas cylinder valve is arranged on the branch pipeline at the joint of the raw material gas cylinder and the branch pipeline, and a to-be-filled gas cylinder valve is arranged on the to-be-filled pipeline at the joint of the to-be-filled gas cylinder and the to-be-filled pipeline; according to the utility model, by arranging a structure for filling a plurality of gas cylinders to be filled at the same time, the gas cylinder filling efficiency is higher, and the filling speed is higher.

Description

Technical Field

[0001] The utility model belongs to the field of preparation of gas reference materials, and particularly relates to a batch preparation device for gas reference materials. Background Art

[0002] At present, the gravimetric method for preparing gas reference materials is a widely used method at home and abroad. The gravimetric method is only applicable to gas mixtures of gaseous or fully vaporizable components, and there is no reaction between the components of the gas mixture and between each component and the bottle wall.

[0003] The gravimetric method for preparing standard gas mixtures is to transfer the gas mixture with known components and concentrations into gas cylinders, and use a high-load precision balance to weigh the mass of the gas cylinders before and after filling. The difference between the two weighings is the amount of the component gas added.

[0004] First, determine the filling pressure and the composition of the raw gas, and safety factors such as potential mutual reactions between the components of the gas mixture and between the components and the gas cylinder need to be considered. Then, determine the filling method, namely the direct dilution method, the multi-stage dilution method, and the transfer method. According to the theoretical calculation, the mass of the gas components to be filled is obtained for direct dilution or multi-stage dilution; finally, the final concentration and uncertainty of the gas mixture components are calculated according to the actual mass of the filled gas.

[0005] The existing gravimetric preparation technology mainly prepares gas reference materials bottle by bottle. However, in actual situations, the efficiency of preparing gas reference materials bottle by bottle is low, and multiple gas reference materials cannot be quickly prepared.

[0006] Therefore, how to provide a batch preparation device for gas reference materials is an urgent problem to be solved by those skilled in the art. Summary of the Utility Model

[0007] The main purpose of the utility model is to provide a batch preparation device for gas reference materials to solve the above technical problems. The device makes the filling of gas cylinders more efficient and faster by setting a structure for simultaneously filling multiple gas cylinders to be filled.

[0008] To achieve the above purpose, the utility model adopts the following technical solutions:

[0009] A batch preparation device for gas reference materials, comprising a vacuum pump, a raw material gas cylinder and a gas cylinder to be filled. The vacuum pump is connected to one end of a main pipeline, and the other end of the main pipeline is connected to one end of two branch pipelines. The other ends of the two branch pipelines are respectively connected to the raw material gas cylinder and a balancer. The balancer is also connected to one end of a plurality of pipelines to be filled, and the other ends of the plurality of pipelines to be filled are all connected to the gas cylinder to be filled. Pipeline valves are provided on the pipelines to be filled, the two branch pipelines and the main pipeline. A raw material gas cylinder valve is provided on the branch pipeline at the connection of the raw material gas cylinder and the branch pipeline, and a gas cylinder valve to be filled is provided on the pipeline to be filled at the connection of the gas cylinder to be filled and the pipeline to be filled.

[0010] Further, a vent pipeline and a balance pipeline are also connected to the main pipeline. The end of the vent pipeline far from the main pipeline extends to a gas vent collection place. The end of the balance pipeline far from the main pipeline is connected to a balance gas cylinder. A gas vent valve is provided on the vent pipeline, and a balance gas cylinder valve is provided on the balance pipeline.

[0011] Further, a vacuum gauge is provided on the main pipeline, a low-precision pressure gauge is provided on the branch pipeline connected to the pipeline to be filled, and a high-precision pressure gauge is provided on the pipeline to be filled.

[0012] Compared with the prior art, the present utility model has the following beneficial effects:

[0013] By setting a structure for simultaneously filling a plurality of gas cylinders to be filled, the present utility model has a higher filling efficiency and a faster filling speed for the gas cylinders.

[0014] The present utility model changes the original method of preparing standard gases one by one by the weighing method to a method of passing the raw material gas through a balancer device. By designing the materials, diameters and lengths of the connecting pipelines of the balancer to be the same, the effects of the same resistance, pressure and flow rate of the gas passing through the balancer are achieved, so as to control the same quality of the filled gas and achieve the purpose of simultaneously preparing multiple bottles of standard gases with the same concentration. The preparation process of the present utility model is easy to operate, the results are accurate and reliable, and the preparation efficiency is greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0016] Figure 1 It is a schematic structural diagram of the present utility model.

[0017] Among them, 1 - raw material gas cylinder, 2 - cylinder to be filled, 3 - valve of the cylinder to be filled, 4 - pipeline valve, 5 - vacuum gauge, 6 - low-precision pressure gauge, 7 - high-precision pressure gauge, 8 - vacuum pump, 9 - valve of the raw material gas cylinder, 10 - gas vent valve, 11 - valve of the balance gas cylinder, 12 - balancer. Detailed implementation manners

[0018] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0019] As Figure 1 shown, the present invention provides a batch preparation device for gas reference materials, including a vacuum pump 8, a raw material gas cylinder 1, and a cylinder 2 to be filled. One end of the vacuum pump 8 is connected to one end of the main pipeline, and the other end of the main pipeline is connected to one end of two branch pipelines. The other ends of the two branch pipelines are respectively connected to the raw material gas cylinder 1 and the balancer 12. The balancer 12 is also connected to one end of a plurality of pipelines to be filled. The other ends of the plurality of pipelines to be filled are all connected to the cylinder 2 to be filled. Pipeline valves 4 are provided on the pipelines to be filled, the two branch pipelines, and the main pipeline. A valve 9 of the raw material gas cylinder is provided on the branch pipeline at the connection of the raw material gas cylinder 1 and the branch pipeline. A valve 3 of the cylinder to be filled is provided on the pipeline to be filled at the connection of the cylinder 2 to be filled and the pipeline to be filled; the vacuum pump 8 is used to evacuate the gas in the main pipeline, the branch pipelines, and the pipelines to be filled to form a vacuum environment; the raw material gas cylinder 1 is used to store the gas to be filled; the cylinder 2 to be filled is used to fill the gas; the materials, diameters, lengths, etc. of the balancer 12 connecting the pipelines to be filled and the branch pipelines are the same, achieving the effect that the gas has the same resistance, pressure, and flow rate when passing through the balancer, so as to control the same quality of the filled gas and achieve the purpose of simultaneously preparing multiple bottles of standard gases with the same concentration.

[0020] In this embodiment, an exhaust pipeline and a balance pipeline are further connected to the main pipeline. One end of the exhaust pipeline far from the main pipeline extends to the gas exhaust collection place. One end of the balance pipeline far from the main pipeline is connected to a balance gas cylinder. A gas vent valve 10 is provided on the exhaust pipeline, and a valve 11 of the balance gas cylinder is provided on the balance pipeline; the gas vent valve 10 on the exhaust pipeline is used to discharge the gas in the main pipeline, the branch pipelines, and the pipelines to be filled; the valve 11 of the balance gas cylinder on the balance pipeline is used to fill nitrogen into the main pipeline, the branch pipelines, and the pipelines to be filled; the balance gas cylinder is filled with balance gas nitrogen.

[0021] In this embodiment, a vacuum gauge 5 is provided on the main pipeline, a low-precision pressure gauge 6 is provided on the branch pipeline connected to the pipeline to be filled, and a high-precision pressure gauge 7 is provided on the pipeline to be filled. The vacuum gauge 5 is used to detect the vacuum degree of the main pipeline, the branch pipeline and the pipeline to be filled. The detectable range of the low-precision pressure gauge 6 is (0 - 25 MPa), and the detectable pressure range of the high-precision pressure gauge 7 is (0 - 4 MPa).

[0022] According to: P i = P 0 * X i

[0023] Wherein:

[0024] <![CDATA[P i > The pressure of component i in the mixed gas, in MPa <![CDATA[P 0 > The final filling pressure of the mixed gas, in MPa <![CDATA[X i > The concentration of component i in the mixed gas

[0025] Introduction to the example of batch preparation of standard gas:

[0026] Initial parameters: oxygen in 20% nitrogen; pressure: 9.5 MPa; N 2 : 99.999%, O 2 : 99.999%; 8L aluminum alloy steel cylinder;

[0027] A method for batch preparation of a gas reference material, comprising the following steps:

[0028] S1. Connect all cylinders 2 to be filled to the pipeline to be filled. At this time, the cylinder valves 3 of the cylinders to be filled, the cylinder valves 9 of the raw material cylinders, the gas vent valves 10, the cylinder valves 11 of the balance gas cylinders and all pipeline valves 4 are in the closed state;

[0029] S2. Open all pipeline valves 4, and then turn on the vacuum pump 8 to evacuate the main pipeline, the branch pipeline and the pipeline to be filled. The vacuum degree is not higher than 3 Pa (measured by the vacuum gauge 8);

[0030] S3. Close the vacuum pump 8 and the pipeline valve 4 on the main pipeline, then open the cylinder valve 11 of the balance gas cylinder, fill the main pipeline, the branch pipeline and the pipeline to be filled with balance gas (nitrogen), and then close the cylinder valve 11 of the balance gas cylinder;

[0031] S4. Then open the gas vent valve 10 to vent the balance gas in the main pipeline, the branch pipeline and the pipeline to be filled, then close the gas vent valve 10, open the pipeline valve 4 on the main pipeline, start the vacuum pump 8, and evacuate the pressure in the pipeline to about 3 Pa (measured by the vacuum gauge 8), and then close the pipeline valve 4 on the main pipeline;

[0032] S5. Repeat steps S2 - S4 at least 3 times;

[0033] S6. Slowly open the raw material gas cylinder valve 9 on the raw material gas cylinder 1 and the gas cylinder valve 3 of the gas cylinder to be filled, and fill the gas components into the gas cylinder 2 to be filled.

[0034] S7. Observe the pressure change of the high-precision pressure gauge 7 (0 - 4 MPa). When the reading of the high-precision pressure gauge 7 reaches the target filling pressure, after a certain period of time, observe whether the indication of the high-precision pressure gauge 7 is stable. After it is stable, close the raw material gas cylinder valve 9, and then close the gas cylinder valve 3 of the gas cylinder to be filled in sequence.

[0035] S8. Close the raw material gas cylinder valve 9 and the pipeline valve 4 on the branch pipeline connecting the raw material gas cylinder 1, open the gas vent valve 10, and discharge the raw material component gas in the main pipeline, branch pipeline, and the pipeline to be filled.

[0036] S9. Close the gas vent valve 10, open the pipeline valve 4 on the main pipeline, start the vacuum pump 8, pump the pressure in the pipeline to about 3 Pa, and then close the pipeline valve 4 on the main pipeline.

[0037] S10. Slowly open the balance gas cylinder valve 11, fill the balance gas nitrogen, observe the reading change of the low-precision pressure gauge 6 (0 - 25 MPa). When the reading reaches the target filling pressure, close the gas cylinder valve 3 of the target gas cylinder to be filled.

[0038] S11. Close the balance gas cylinder valve 11, open the gas vent valve 10, and discharge the balance gas nitrogen in all pipelines.

[0039] S12. Mix the mixed gas, for example, by rolling the gas cylinders. The prepared gas reference material is obtained in the gas cylinder 2 to be filled. According to the filling pressure, the concentration of oxygen in nitrogen can be calculated to be 20.0%. Analyze the oxygen content of multiple bottles of 20.0% oxygen in nitrogen standard gas prepared by using a fuel cell oxygen analyzer, and the analysis result is consistent with the calculation result.

[0040] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and for the relevant parts, reference can be made to the description in the method part.

[0041] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A batch preparation device for gas standard substances, characterized in that: The invention comprises a vacuum pump (8), a raw gas cylinder (1) and a gas cylinder to be filled (2), wherein the vacuum pump (8) is connected to one end of a main pipeline, the other end of the main pipeline is connected to one end of two branch pipelines, the other ends of the two branch pipelines are respectively connected to the raw gas cylinder (1) and a balancer (12), the balancer (12) is also connected to one end of a plurality of pipelines to be filled, the other ends of the plurality of pipelines to be filled are all connected to the gas cylinder to be filled (2), the pipeline to be filled, the two branch pipelines and the main pipeline are all provided with pipeline valves (4), the branch pipeline at the connection between the raw gas cylinder (1) and the branch pipeline is provided with a raw gas cylinder valve (9), and the pipeline to be filled is provided with a gas cylinder valve (3) at the connection between the gas cylinder to be filled (2) and the pipeline to be filled.

2. The batch preparation device for gas standard substances according to claim 1, characterized in that: The main pipeline is also connected to a venting pipeline and a balancing pipeline. The end of the venting pipeline away from the main pipeline extends to a gas venting collection point. The end of the balancing pipeline away from the main pipeline is connected to a balancing gas cylinder. The venting pipeline is provided with a gas venting valve (10), and the balancing pipeline is provided with a balancing gas cylinder valve (11).

3. The batch preparation device for gas standard substances according to claim 1, characterized in that: The main pipeline is provided with a vacuum gauge (5), the branch pipeline connected to the pipeline to be filled is provided with a low-precision pressure gauge (6), and the pipeline to be filled is provided with a high-precision pressure gauge (7).

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