Low consumption carrier gas cylinder connection switching device for ultrapure ammonia detection instrument

Abstract

The utility model discloses a kind of ultra-pure ammonia detection instrument low consumption carrier gas gas cylinder intercommunication switching device, including detection instrument, gas cylinder, intercommunication switching valve group is equipped between detection instrument and gas cylinder, pressure reducing valve, gas cylinder is equipped at least one, intercommunication switching valve group includes tee valve, vent valve, inlet valve, vent valve, inlet valve, the outlet valve of gas cylinder is connected with tee valve respectively, inlet valve is converged to pressure reducing valve, and pressure reducing valve is connected with detection instrument. After using the device, the helium gas consumed by replacement pipeline is reduced from about 1L / time to about 100ml / time;Replacement pipeline is more thorough, no dead gas remains, after replacing gas cylinder, analysis instrument data is almost undulation, can carry out sustained production, and the original gas cylinder needs about 16h time to make analysis instrument data stable after replacing, during which product cannot be discharged, and each time causes about 6.4t production reduction.

Description

Technical Field

[0001] This utility model relates to a gas cylinder connection device, and more particularly to a low-consumption carrier gas cylinder connection and switching device for an ultrapure ammonia detection instrument. Background Technology

[0002] The Pulse Discharge Helium Ionization Detector (PDHID) is a highly sensitive universal detector with a high response to almost all inorganic and organic compounds. It is particularly suitable for the analysis of high-purity gases and is the only detector capable of detecting down to the ppb level. The sample liquid ammonia is delivered to the PDD pretreatment chamber in the online analysis room via a sampling line on the high-boiling-point reflux line. The liquid ammonia sample is gradually vaporized into a gaseous phase in the sampling line using electric heating. The gaseous ammonia sample is then carried into the directional ring of the PDD helium ionization detector via the carrier gas (He) through the analysis pipeline. After separation by the chromatographic column, the gaseous ammonia sample enters the PDD detector for detection.

[0003] Carrier gas (He) is delivered to the testing instrument via a pipeline connected to a gas cylinder. The cylinder must be replaced with a new full cylinder before it runs out of helium. After replacing the cylinder, the delivery pipeline must be thoroughly purged to prevent air from being introduced, which could distort the analytical data or even damage the instrument. When replacing the full cylinder, the inlet valve is closed, and after connecting the pipeline to the cylinder, the vent valve must be opened to purge the pipeline. However, using this purging method with existing connecting pipelines would waste gas and would not easily remove stagnant gas from the inlet valve section, contaminating the pipeline and causing unstable analytical data, thus affecting efficiency. Utility Model Content

[0004] Purpose of the utility model: In view of the above problems, the purpose of this utility model is to provide a low-consumption carrier gas cylinder connection and switching device for an ultrapure ammonia detection instrument, which ensures thorough replacement of the pipeline without any dead gas residue, and that the pipeline is well sealed at all points.

[0005] Technical solution: A low-consumption carrier gas cylinder connection and switching device for an ultrapure ammonia detection instrument, comprising a detection instrument and a gas cylinder, wherein a connection and switching valve group and a pressure reducing valve are provided between the detection instrument and the gas cylinder, and at least one gas cylinder is provided. The connection and switching valve group includes a three-way valve, a vent valve, and an inlet valve. The vent valve, the inlet valve, and the outlet valve of the gas cylinder are respectively connected to the three-way valve. The inlet valve is connected to the pressure reducing valve, and the pressure reducing valve is connected to the detection instrument.

[0006] Furthermore, there are at least two gas cylinders, and the outlet valve of each gas cylinder is connected to a connecting switching valve group. The connecting switching valve groups are connected in parallel and are respectively connected to a pressure reducing valve.

[0007] The optimal vent valve model is ball valve BV-MS.

[0008] Ideally, the pressure reducing valve model is Sa-1H.

[0009] Ideally, the three-way valve should be a three-way rotary valve.

[0010] Ideally, all connections between valves and pipes in the device should be sealed.

[0011] During the gas cylinder replacement process, when opening the vent valve to replace the pipeline, it is essential to ensure that the pipeline is completely purged without any residual dead gas, and that all parts of the pipeline are properly sealed.

[0012] Before replacing the gas cylinder, close the inlet valve by switching the three-way valve to ensure that the inlet pipe of the three-way valve is uncontaminated during the replacement process. After connecting the front-end pipe to the gas cylinder, open the outlet valve of the gas cylinder and use the vent valve to purge the pipe between the gas cylinder interface and the three-way valve that has come into contact with air and is contaminated. Other pipes that have not come into contact with air do not need to be purged. After purging, switch to the inlet pipe and open the inlet valve to complete the replacement. By controlling the gas cylinder replacement using the three-way valve, the replacement time is short, the gas consumption is small, and the pipe replacement is thorough.

[0013] Beneficial effects: Compared with the prior art, the advantages of this utility model are:

[0014] 1. After using this device, the amount of helium required to replace the pipeline is reduced from approximately 1L / time to approximately 100ml / time;

[0015] 2. After using this device, the pipeline replacement is more thorough, with no dead gas residue. After replacing the gas cylinder, the analytical instrument data is almost stable, allowing for continuous production. In contrast, after replacing the original gas cylinder, it takes about 16 hours for the analytical instrument data to stabilize, during which time product discharge is impossible, resulting in a reduction of about 6.4 tons of output each time. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model. Detailed Implementation

[0017] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0018] A low-consumption carrier gas cylinder switching device for an ultrapure ammonia detection instrument, such as Figure 1 As shown, it includes a testing instrument 100, a gas cylinder 200, a connecting switching valve group, and a pressure reducing valve 5.

[0019] A connecting switching valve group and a pressure reducing valve 5 are provided between the testing instrument 100 and the gas cylinder 200. There is at least one gas cylinder 200. When there are two or more gas cylinders 200, the outlet valve 1 of each gas cylinder 200 is connected to a connecting switching valve group. The connecting switching valve groups are connected in parallel and are connected to the pressure reducing valve 5 respectively. All valves and pipelines in the device are sealed.

[0020] The connecting switching valve group includes a three-way valve 2, a vent valve 3, and an inlet valve 4. The vent valve 3, the inlet valve 4, and the outlet valve 1 of the gas cylinder 200 are respectively connected to the three-way valve 2. The inlet valve 4 flows to the pressure reducing valve 5, and the pressure reducing valve 5 is connected to the testing instrument 100.

[0021] The vent valve can be a ball valve BV-MS, material: 316L, model: 1 / 4 ferrule, 1 / 4 ferrule, high pressure 3000psi; the pressure reducing valve can be a pressure reducing device Sa-1H, material: 316L, model: 25MPa, 2.5MPa, 1 / 4 ferrule, 1 / 4 ferrule; the three-way valve can be a three-way rotary valve, material: 316L, model: 25MPa, 1 / 4 ferrule, 1 / 4 ferrule, 1 / 4 ferrule.

[0022] When performing the valve group switching operation, first switch the three-way valve to the vent pipe connected to the vent valve before replacing the gas cylinder with the new one. After the new gas cylinder is replaced, open the outlet valve of the gas cylinder to allow gas to flow to the vent valve for purging and replacement. After replacement, close the vent valve, switch the three-way valve to the inlet pipe connected to the inlet valve, open the inlet valve to supply auxiliary gas, and loosen the low-pressure regulating lever of the gas cylinder. Open the high-pressure valve of the gas cylinder and then slowly adjust the low-pressure regulating lever until the low-pressure gauge indicates 0.5 MPa; close the high-pressure valve of the gas cylinder. At this time, the low-pressure gauge on the pressure reducing valve should not drop. Otherwise, there is a leak in the external gas line, which should be carefully checked and eliminated. After completing the gas cylinder replacement, the analytical instrument can be put into production use.

Claims

1. A low-consumption carrier gas cylinder switching device for an ultrapure ammonia detection instrument, comprising a detection instrument (100) and a gas cylinder (200), characterized in that: A connecting switching valve group and a pressure reducing valve (5) are provided between the testing instrument (100) and the gas cylinder (200). The gas cylinder (200) has at least one such valve. The connecting switching valve group includes a three-way valve (2), a vent valve (3), and an inlet valve (4). The vent valve (3), the inlet valve (4), and the outlet valve (1) of the gas cylinder (200) are respectively connected to the three-way valve (2). The inlet valve (4) flows to the pressure reducing valve (5), and the pressure reducing valve (5) is connected to the testing instrument (100).

2. The low-consumption carrier gas cylinder switching device for an ultrapure ammonia detection instrument according to claim 1, characterized in that: At least two gas cylinders (200) are provided. The outlet valve (1) of each gas cylinder (200) is connected to a connecting switching valve group. The connecting switching valve groups are connected in parallel and are respectively connected to the pressure reducing valve (5).

3. The low-consumption carrier gas cylinder switching device for an ultrapure ammonia detection instrument according to claim 1, characterized in that: The vent valve (3) is a ball valve BV-MS.

4. The low-consumption carrier gas cylinder switching device for an ultrapure ammonia detection instrument according to claim 1, characterized in that: The pressure reducing valve (5) is model Sa-1H.

5. The low-consumption carrier gas cylinder switching device for an ultrapure ammonia detection instrument according to claim 1, characterized in that: The three-way valve (2) is a three-way rotary valve.

6. The low-consumption carrier gas cylinder switching device for an ultrapure ammonia detection instrument according to claim 1, characterized in that: All valve and pipeline connections in the device are sealed.

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