Preparation device of liquid component standard gas

Abstract

The utility model discloses a preparation device of liquid component standard gas, which belongs to the technical field of standard gas preparation equipment and is characterized in that heating wires are mounted at two ends outside a cavity, a heat insulation protection layer is arranged outside the cavity and the heating wires, and a microsyringe penetrates through the heat insulation protection layer to be communicated with the cavity through a pipeline. The vacuum pump, the bottom gas pipe and the blow-down pipe are respectively communicated with the breather pipe, the breather pipe is communicated with the cavity, the standard gas cylinder is communicated with the cavity, a valve A is arranged on a pipeline for communicating the micro-pressure gauge and the breather pipe, a valve B is arranged on a pipeline for communicating the vacuum pump and the breather pipe, and the valve A is communicated with the valve B; a valve C is mounted on the bottom gas pipe, a valve D is mounted on the blow-down pipe, and a valve E is mounted on a pipeline for communicating the standard gas cylinder with the cavity. The device disclosed by the utility model can be used for trace preparation, and liquid cannot be remained on the sample injection valve and cannot be attached to the side wall of the standard gas cylinder due to the action of negative pressure, so that the error is smaller.

Description

Technical Field

[0001] The utility model belongs to the technical field of standard gas preparation equipment, and more specifically relates to a device for preparing a standard gas of liquid components. Background Art

[0002] The main method for preparing standard gas is the weighing method. First, weigh the empty bottle, then calculate the mass of each component required for the target concentration using the ideal gas state equation, and use a precision balance to weigh each component. In the prior art, the standard gas of liquid components is mainly prepared by the method of direct injection with a micro syringe, that is, use a micro syringe to suck in the liquid component, connect the injection valve and the standard gas cylinder, open the injection valve, then place the micro syringe at the injection valve port, open the valve of the standard gas cylinder that has been vacuum treated in advance, and suck in the liquid component in the micro syringe with negative pressure. After complete inhalation, close the cylinder valve, remove the injection valve, and introduce the background gas calculated according to the ideal gas state equation into the standard gas cylinder. After inflation is completed, close each valve, and the preparation is completed. In the field of standard gas preparation, there have always been many difficulties in the preparation of standard gas of liquid components. In the actual application process of the method of directly injecting liquid components with a micro syringe to prepare standard gas of liquid components currently used, it is impossible for the micro syringe to inject all the liquid completely. At lower concentrations, the mass of the liquid component will be very small. With the existing balance weighing technology, at least more than 5 g needs to be filled to obtain effective weighing data. Therefore, it is impossible to use the weighing method for preparation, so it is necessary to minimize the error in the preparation process.

[0003] After entering the standard gas cylinder, a part of the liquid component will adhere to the inner wall, and even under the action of pressure when the liquid enters the standard gas cylinder, a part of it is still difficult to be vaporized, resulting in the actual concentration value of the standard gas being lower than the target concentration value.

[0004] Therefore, how to provide a device for preparing a standard gas of liquid components is an urgent problem to be solved by those skilled in the art. Summary of the Utility Model

[0005] In view of this, the utility model provides a device for preparing a standard gas of liquid components, which can perform micro-preparation, and due to the action of negative pressure, there will be no residual liquid in the injection valve, nor will it adhere to the side wall of the standard gas cylinder, and the error is smaller.

[0006] In order to achieve the above object, the utility model adopts the following technical scheme:

[0007] An apparatus for preparing a standard gas of liquid components, comprising: a micro syringe, a liquid vaporization device, a sampling valve, a micro pressure gauge, valve A, a vacuum pump, valve B, a bottom gas pipe, valve C, a vent pipe, valve D, a standard gas cylinder, valve E and a ventilation pipe; the liquid vaporization device comprises a cavity, a heating wire and a heat insulation protection layer; heating wires are installed at both outer ends of the cavity, the heat insulation protection layer is arranged outside the cavity and the heating wire, the micro syringe passes through the heat insulation protection layer and is connected to the cavity through a pipeline, a sampling valve is arranged on the pipeline connecting the micro syringe and the cavity, the micro pressure gauge, the vacuum pump, the bottom gas pipe and the vent pipe are respectively connected to the ventilation pipe, the ventilation pipe is connected to the cavity, the standard gas cylinder is connected to the cavity through a pipeline, valve A is installed on the pipeline connecting the micro pressure gauge and the ventilation pipe, valve B is installed on the pipeline connecting the vacuum pump and the ventilation pipe, valve C is installed on the bottom gas pipe, the bottom gas pipe is used for filling the inside of the standard gas cylinder with bottom gas, valve D is installed on the vent pipe, and valve E is installed on the pipeline connecting the standard gas cylinder and the cavity.

[0008] Furthermore, a pressure gauge is also connected to the ventilation pipe, and valve F is installed on the pipeline connecting the pressure gauge and the ventilation pipe.

[0009] Furthermore, valve G is installed on the ventilation pipes between the bottom gas pipe, the vent pipe and the pressure gauge and the vacuum pump.

[0010] The beneficial effects of the present utility model are as follows:

[0011] 1) During the preparation of the standard gas of liquid components, after being processed by the liquid vaporization device, the liquid components turn into gas and enter the standard gas cylinder. Compared with the traditional method of directly injecting liquid components, the vaporized liquid components are not easily attached to the inner wall of the gas cylinder and can be evenly distributed inside the standard gas cylinder, greatly reducing the error caused during the preparation process.

[0012] 2) After filling the liquid components, when filling the bottom gas into the standard gas cylinder, the bottom gas can purge the residual liquid component gas in the liquid vaporization device and the pipeline, reducing the error.

[0013] 3) Since the vacuum pump is used to evacuate the inside of the cavity to a negative pressure, even for micro-preparation, the micro syringe can inject all the liquid into the cavity with the assistance of the cavity in a negative pressure environment. Description of the Drawings

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the provided drawings.

[0015] Figure 1 It is a schematic structural diagram of the present invention.

[0016] Figure 2 It is a schematic structural diagram of the liquid vaporization device of the present invention.

[0017] Among them, in the figure:

[0018] 1 - Microsyringe; 2 - Liquid vaporization device; 21 - Cavity; 22 - Heating wire; 23 - Thermal insulation protective layer; 3 - Sampling valve; 4 - Micro pressure gauge; 5 - Valve A; 6 - Vacuum pump; 7 - Valve B; 8 - Bottom gas pipe; 9 - Valve C; 10 - Vent pipe; 11 - Valve D; 12 - Pressure gauge; 13 - Valve F; 14 - Valve G; 15 - Standard gas cylinder; 16 - Valve E; 17 - Vent pipe. Specific embodiments

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the 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 belong to the scope of protection of the present invention.

[0020] Please refer to the attached Figure 1-2, the present utility model provides a preparation device for a liquid component standard gas, comprising: a micro syringe 1, a liquid vaporization device 2, a sampling valve 3, a micro pressure gauge 4, a valve A 5, a vacuum pump 6, a valve B 7, a bottom gas pipe 8, a valve C 9, a vent pipe 10, a valve D 11, a standard gas cylinder 15, a valve E 16 and a ventilation pipe 17; the liquid vaporization device 2 includes a cavity 21, a heating wire 22 and a heat insulation protective layer 23; heating wires 22 are installed at both outer ends of the cavity 21, and the heat insulation protective layer 23 is arranged outside the cavity 21 and the heating wires 22. The micro syringe 1 passes through the heat insulation protective layer 23 and is connected to the cavity 21 through a pipeline. An injection valve 3 is arranged on the pipeline connecting the micro syringe 1 and the cavity 21. The micro pressure gauge 4, the vacuum pump 6, the bottom gas pipe 8 and the vent pipe 10 are respectively connected to the ventilation pipe 17. The ventilation pipe 17 is connected to the cavity 21. The standard gas cylinder 15 is connected to the cavity 21 through a pipeline. A valve A 5 is installed on the pipeline connecting the micro pressure gauge 4 and the ventilation pipe 17. A valve B 7 is installed on the pipeline connecting the vacuum pump 6 and the ventilation pipe 17. A valve C 9 is installed on the bottom gas pipe 8. The bottom gas pipe 8 is used to fill the inside of the standard gas cylinder 15 with base gas. A valve D 11 is installed on the vent pipe 10. A valve E 16 is installed on the pipeline connecting the standard gas cylinder 15 and the cavity 21. The heat insulation protective layer 23 can reduce the operation risk and protect the safety of the operator. The temperature of the heating wire 22 is set at different temperatures according to the boiling points of different liquid components. When filling the base gas, the liquid vaporization device 2 and the pipeline are purged, so that the preparation is more accurate and the error is reduced.

[0021] A pressure gauge 12 is further connected to the ventilation pipe 17. A valve F 13 is installed on the pipeline connecting the pressure gauge 12 and the ventilation pipe 17.

[0022] A valve G 14 is installed on the ventilation pipe 17 between the bottom gas pipe 8, the vent pipe 10 and the pressure gauge 12 and the vacuum pump 6.

[0023] The present utility model is operated according to the following steps when in use:

[0024] S1. According to m 液 =X 液 PVM 液 / RTZ, calculate the mass of the liquid component to be filled, where m 液 is the mass of the liquid component to be filled, in g, X 液 is the target concentration of the liquid component, in mol / mol, P is the final filling pressure of the standard gas cylinder, in Pa, V is the volume of the standard gas cylinder, in m 3 , M 液where \(M\) is the molar mass of the liquid component in g / mol, \(R\) is the gas constant (8.31451 J / mol×K), \(T\) is the ambient temperature in K, and \(Z\) is the compressibility factor at temperature \(T\) and pressure \(P\).

[0025] S2. Calculate the volume of the liquid component to be filled according to \(V = m / \rho\), where \(V\) is the volume of the liquid component to be filled, \(m\) is the mass of the liquid component to be filled, and \(\rho\) is the density of the liquid component. 液 =m 液 / ρ 液 Calculate the volume of the liquid component to be filled according to \(V = m / \rho\), where \(V\) is the volume of the liquid component to be filled, \(m\) is the mass of the liquid component to be filled, and \(\rho\) is the density of the liquid component. 液 is the volume of the liquid component to be filled, \(m\) 液 is the mass of the liquid component to be filled, and \(\rho\) 液 is the density of the liquid component.

[0026] S3. Close the injection valve 3, valve A5, valve C9, and valve D11. Open the vacuum pump 6, and open valve E16, valve B7, valve G14, and valve F13 to evacuate the standard gas cylinder 15, the cavity 21, and the pipeline.

[0027] S4. After the reading of the pressure gauge 12 stabilizes, close valve E16, valve B7, and valve G14. Use a micro syringe 1 to aspirate the target volume of the liquid component. Open the injection valve 3, and use negative pressure to suck the liquid component in the micro syringe 1 into the cavity 21. After all is sucked in, close the injection valve 3 and open valve A5.

[0028] S5. Turn on the switch of the liquid vaporization device 2, and start vaporizing the liquid component using the heating wire 22. Wait until the reading of the micro pressure gauge 4 no longer changes, indicating complete vaporization.

[0029] S6. Close valve A5, open valve E16, and use the negative pressure in the standard gas cylinder 15 to suck the vaporized liquid component in the cavity 21 into the standard gas cylinder 15. Then close valve E16.

[0030] S7. Calculate the mass of the base gas to be filled according to \(m = X\frac{PVM}{RTZ}\), where \(m\) is the mass of the base gas required in g, \(X\) is the target concentration of the base gas component in mol / mol, \(P\) is the final filling pressure of the standard gas cylinder in Pa, \(V\) is the volume of the standard gas cylinder in \(m^3\), \(M\) is the molar mass of the liquid component in g / mol, \(R\) is the gas constant (8.31451 J / mol×K), \(T\) is the ambient temperature in K, and \(Z\) is the compressibility factor at temperature \(T\) and pressure \(P\). Calculate the required mass of the base gas. 底 =X 底 PVM 底 / RTZ Calculate the mass of the base gas to be filled according to \(m = X\frac{PVM}{RTZ}\), where \(m\) 底 is the mass of the base gas required, in g, \(X\) 底 is the target concentration of the base gas component, in mol / mol, \(P\) is the final filling pressure of the standard gas cylinder, in Pa, \(V\) is the volume of the standard gas cylinder, in \(m^3\), 3 M 底 is the molar mass of the liquid component, in g / mol, \(R\) is the gas constant (8.31451 J / mol×K), \(T\) is the ambient temperature, in K, and \(Z\) is the compressibility factor at temperature \(T\) and pressure \(P\).

[0031] S8. Place the standard gas cylinder 15 on a precision balance. Open valves C9, F13, and E16 to zero the precision balance. Control P5 to fill the standard gas cylinder 1 to the target mass and then close valves E16, G14, and C9.

[0032] S9. Open valve D11 to vent the excess base gas, remove the standard gas cylinder 15, and the preparation is completed.

[0033] In this specification, the various embodiments are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple. For the relevant parts, reference can be made to the description in the method section.

[0034] 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. An apparatus for preparing a standard gas of liquid components, characterized in that, Including: A micro syringe (1), a liquid vaporization device (2), a sampling valve (3), a micro pressure gauge (4), a valve A (5), a vacuum pump (6), a valve B (7), a bottom gas pipe (8), a valve C (9), a vent pipe (10), a valve D (11), a standard gas cylinder (15), a valve E (16) and a ventilation pipe (17); the liquid vaporization device (2) includes a cavity (21), a heating wire (22) and a heat insulation protection layer (23); heating wires (22) are installed at both outer ends of the cavity (21), the heat insulation protection layer (23) is arranged outside the cavity (21) and the heating wire (22), the micro syringe (1) passes through the heat insulation protection layer (23) and is communicated with the cavity (21) through a pipeline, a sampling valve (3) is arranged on the pipeline where the micro syringe (1) is communicated with the cavity (21), the micro pressure gauge (4), the vacuum pump (6), the bottom gas pipe (8) and the vent pipe (10) are respectively communicated with the ventilation pipe (17), the ventilation pipe (17) is communicated with the cavity (21), the standard gas cylinder (15) is communicated with the cavity (21) through a pipeline, a valve A (5) is installed on the pipeline where the micro pressure gauge (4) is communicated with the ventilation pipe (17), a valve B (7) is installed on the pipeline where the vacuum pump (6) is communicated with the ventilation pipe (17), a valve C (9) is installed on the bottom gas pipe (8), the bottom gas pipe (8) is used for filling the inside of the standard gas cylinder (15) with bottom gas, a valve D (11) is installed on the vent pipe (10), and a valve E (16) is installed on the pipeline where the standard gas cylinder (15) is communicated with the cavity (21).

2. The preparation device of a standard gas of liquid components according to claim 1, characterized in that, A pressure gauge (12) is further connected to the ventilation pipe (17), and a valve F (13) is installed on the pipeline where the pressure gauge (12) is communicated with the ventilation pipe (17).

3. The preparation device of a standard gas of liquid components according to claim 2, characterized in that, A valve G (14) is installed on the ventilation pipe (17) between the bottom gas pipe (8), the vent pipe (10) and the pressure gauge (12) and the vacuum pump (6).

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