Methane detection device used in krypton-xenon-containing liquid oxygen production system

Abstract

The utility model relates to a methane detection device used in a krypton-xenon-containing liquid oxygen production system. Comprising a de-heavy rectifying tower in a liquid oxygen production system, a reboiler connected with a heat source nitrogen pipeline is arranged in the de-heavy rectifying tower, a detection pipeline and a tower kettle liquid discharge pipeline are arranged at the bottom of the de-heavy rectifying tower, and the tower kettle liquid discharge pipeline is connected with a krypton-xenon concentrate storage tank of a subsequent working section. The detection pipeline is connected with the methane detection unit through the gasification uniform mixing unit; the device has the characteristics that the content of methane in the tower kettle liquid in the de-heavy rectifying tower can be monitored in real time, so that the de-heavy rectifying tower can stably run for a long time under the condition that the risk is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of methane content detection, especially to a methane detection device used in a krypton-xenon-containing liquid oxygen production system. BACKGROUND

[0002] Krypton and xenon are rare gases, which have important uses in many industrial and scientific fields, such as semiconductor manufacturing, lighting, low-temperature superconducting research, etc. in the electronic industry. However, impurities such as methane are often mixed in the production process of extracting krypton-xenon concentrate. Specifically, krypton and xenon mainly exist in liquid oxygen, and as krypton and xenon are concentrated, the hydrocarbons in the gas mixture will also be concentrated (because their boiling points are close to those of krypton and xenon). In the presence of a large amount of oxygen, the concentration of methane, a hydrocarbon, poses an explosion risk. Therefore, it is important to control the content of methane, a hydrocarbon, in liquid oxygen during the process of extracting krypton-xenon mixture. Further, methane exists in liquid state in the tower kettle of the rectifying column, so methane is not uniformly distributed in liquid oxygen. Under the influence of pressure and temperature, the gasification process is unstable, which ultimately leads to fluctuations in the analyzed methane content, frequent adjustments of the system, and safety risks. Therefore, how to accurately detect the content of methane to ensure stable operation of the rectifying column has become a technical problem to be solved. SUMMARY

[0003] The utility model aims at solving the defects in the prior art and provides a methane detection device used in a krypton-xenon-containing liquid oxygen production system.

[0004] To achieve the above-mentioned purpose, the utility model provides the following technical scheme:

[0005] A methane detection device used in a krypton-xenon-containing liquid oxygen production system, the detection device comprising a heavy-removal rectifying column in the liquid oxygen production system, a reboiler connected to a heat source nitrogen gas pipeline in the interior of the heavy-removal rectifying column, a detection pipeline and a tower kettle liquid discharge pipeline provided at the bottom of the heavy-removal rectifying column, the tower kettle liquid discharge pipeline being connected to a krypton-xenon concentrate storage tank in a subsequent process section, and the detection pipeline being connected to a methane detection unit through a gasification and uniform mixing unit.

[0006] The utility model has the beneficial effects that: the utility model sets a methane detection unit for detecting the content of methane in the heavy-removal rectifying column in the liquid oxygen production system to realize real-time monitoring of the content of methane in the tower kettle liquid in the heavy-removal rectifying column, thereby realizing long-term stable operation of the heavy-removal rectifying column with reduced risk. Specifically, the utility model uses a gasification and uniform mixing unit to gasify the tower kettle liquid and make the gas phase after gasification in a homogeneous state, thereby laying a foundation for accurate detection of the content of methane.

[0007] Preferably, the gasification and mixing unit comprises at least a water bath vaporizer and a gas phase mixing assembly connected to the water bath vaporizer.

[0008] Preferably, the gas phase mixing assembly comprises at least a first buffer tank and a second buffer tank connected in series, the inlet of the first buffer tank is connected to the outlet of the water bath vaporizer, and the outlet of the second buffer tank is connected to the methane detection unit.

[0009] Preferably, the gas phase mixing assembly further comprises a connecting pipeline arranged between the outlet of the second buffer tank and the methane detection unit, and the length of the connecting pipeline is 10-15 meters.

[0010] Preferably, the methane detection unit comprises an analysis panel, the inlet of the analysis panel is connected to the connecting pipeline, the outlet of the analysis panel is connected to an analysis instrument through a filter, and a sample gas outlet pipeline is arranged on the analysis instrument.

[0011] Preferably, an adjusting valve and a flow meter are arranged between the filter and the analysis instrument.

[0012] Preferably, a liquid oxygen pipeline with a first valve is arranged on the decontamination rectification tower.

[0013] Preferably, a second valve is arranged on the tower kettle liquid discharge pipeline.

[0014] Preferably, a condenser is arranged at the top of the decontamination rectification tower, the liquid phase outlet of the condenser is connected to a reflux tank, a third valve is arranged between the outlet of the lower part of the reflux tank and the reflux liquid inlet of the decontamination rectification tower, and a fourth valve is arranged between the outlet of the lower part of the reflux tank and the liquid oxygen product tank.

[0015] The methane detection device used in the krypton-xenon-containing liquid oxygen production system prepared according to the above scheme mainly detects the methane content in the liquid oxygen production system to ensure the safe operation of the rectification tower. Specifically, it detects the methane content in the tower kettle liquid of the decontamination rectification tower in cooperation with the decontamination rectification tower. The detection pipeline of the decontamination rectification tower passes through the gasification and mixing unit to make the tower kettle liquid into a gaseous state, and cooperates with the gas phase mixing assembly to uniformly mix the gas phase, thereby ensuring the accuracy of the methane content detection and providing data support for the safe operation of the decontamination rectification tower. In the utility model, the water bath vaporizer is arranged in the gasification and mixing unit to realize the gasification of most of the tower kettle liquid, the gas phase mixing assembly is arranged to effectively buffer the pressure fluctuation, promote the separation of gas from liquid, and make the gas fully mixed and uniform, so that the analysis data is more real and stable. Further, the long connecting pipeline can further uniformly mix the gas phase from the buffer tank to realize the characteristic that the gas phase is in a homogeneous state. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The utility model discloses a structure schematic diagram.

[0017] In the drawing,

[0018] 1, the heavy fraction distillation column is removed;2, reboiler;3, krypton-xenon concentrate storage tank;4, water bath vaporizer;5, first buffer tank;6, second buffer tank;7, connecting pipeline;8, analysis panel;9, filter;10, analysis instrument;11, sample gas outlet pipeline;12, regulating valve;13, flow meter;14, liquid oxygen pipeline;15, condenser;16, reflux tank;17, liquid oxygen product tank;18, first valve;19, second valve;20, third valve;21, fourth valve. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments.

[0020] In the description of the utility model, it needs to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, therefore, it cannot be understood as a limitation on the utility model.

[0021] With reference to Figure 1 The utility model discloses a kind of methane detection devices used in krypton-xenon liquid oxygen production system, which includes heavy fraction distillation column 1 in liquid oxygen production system, reboiler 2 connected with heat source nitrogen gas pipeline in the inside of heavy fraction distillation column 1, detection pipeline and tower kettle liquid discharge pipeline are provided at the bottom of heavy fraction distillation column 1, tower kettle liquid discharge pipeline is connected with krypton-xenon concentrate storage tank 3 of subsequent section, detection pipeline is connected with methane detection unit by gasification uniform mixing unit.The methane detection unit in the utility model is used to detect the content of methane in tower kettle liquid in heavy fraction distillation column 1 in real time, and lay foundation for the safe and stable operation of heavy fraction distillation column 1;The gasification uniform mixing unit in the utility model can realize the vaporization of tower kettle liquid, and realize the homogeneity of gas phase after vaporization, to achieve the purpose of accurate detection result;The purpose of the gasification uniform mixing unit in the utility model is mainly to realize the complete vaporization of tower kettle liquid and realize the homogeneity of gas phase after vaporization.

[0022] Further, the gasification and mixing unit comprises at least a water bath vaporizer 4 and a gas phase mixing assembly connected with the water bath vaporizer 4.

[0023] Further, the gas phase mixing assembly comprises at least a first buffer tank 5 and a second buffer tank 6 connected in series, the inlet end of the first buffer tank 5 is connected with the outlet of the water bath vaporizer 4, and the outlet end of the second buffer tank 6 is connected with a methane detection unit. The first buffer tank 5 and the second buffer tank 6 are used to effectively buffer pressure fluctuation, promote gas separation from liquid, realize sufficient mixing of gas, and realize vaporization of a small amount of liquid oxygen.

[0024] Further, the gas phase mixing assembly further comprises a connecting pipeline 7 arranged between the outlet end of the second buffer tank 6 and the methane detection unit, and the length of the connecting pipeline 7 is 10-15 meters. The connecting pipeline 7 is arranged at the rear end of the second buffer tank 6 to realize uniform mixing of gas phase after vaporization of all liquid oxygen.

[0025] Further, the methane detection unit comprises an analysis panel 8, the inlet end of the analysis panel 8 is connected with the connecting pipeline, the outlet end of the analysis panel 8 is connected with an analysis instrument 10 through a filter 9, and a sample gas outlet pipeline 11 is arranged on the analysis instrument 10. The filter 9 is arranged to remove impurities in the gas phase, so as to prolong the service life of the analysis instrument 10. Meanwhile, the pressure difference between the front end and the rear end of the filter 9 can be detected in actual use, so as to judge whether the filter 9 is blocked, and the filter 9 needs to be cleaned when it is blocked.

[0026] Further, an adjusting valve 12 and a flow meter 13 are arranged between the filter 9 and the analysis instrument 10.

[0027] Further, the liquid oxygen pipeline 14 provided on the de-heavy rectification tower 1 is provided with a first valve 18.

[0028] Further, the tower kettle liquid discharge pipeline is provided with a second valve 19.

[0029] Further, the top of the de-heavy rectification tower 1 is provided with a condenser 15, the liquid phase outlet of the condenser 15 is connected with a reflux tank 16, a third valve 20 is arranged between the outlet of the lower part of the reflux tank 16 and the reflux liquid inlet of the de-heavy rectification tower 1, and a fourth valve 21 is arranged between the outlet of the lower part of the reflux tank 16 and a liquid oxygen product tank 17.

[0030] The working principle of the utility model discloses: the liquid oxygen in the liquid oxygen pipeline 14 with the first valve 18 enters the heavy-removing rectifying tower 1 to carry out rectification, the gaseous phase after rectification enters the condenser 15 in the top of the heavy-removing rectifying tower 1 to carry out condensation, the liquid phase after condensation enters the reflux tank 16 and enters the heavy-removing rectifying tower 1 and the liquid oxygen product tank 17 respectively, the tower kettle liquid in the rectification process before enters the krypton-xenon concentrate storage tank 3 through the tower kettle liquid outlet pipeline to be used for purifying krypton-xenon, the methane detection unit detects the methane content in the tower kettle liquid in the operation process of the heavy-removing rectifying tower 1, and the specific process is: the tower kettle liquid of the heavy-removing rectifying tower 1 enters the water bath type vaporizer 4 through the detection pipeline to carry out vaporization (makes most of the tower kettle liquid vaporize), the gas-liquid mixture enters the first buffer tank 5 to effectively buffer pressure fluctuation, promotes the gas to separate from the liquid, makes the gas mix fully and uniformly, and part of the liquid phase vaporizes, then enters the second buffer tank 6 to make the gas mix fully and uniformly and all the liquid oxygen realize vaporization, on the basis, the connecting pipeline 7 can be arranged to realize the uniform mixing of the gaseous phase and be in homogeneous state, the homogeneous gaseous phase first enters the filter 9 after passing through the analysis panel 8 to filter impurities, then the amount of gaseous phase entering the analysis instrument 10 is controlled through the regulating valve 12, and the flow of gaseous phase is monitored through the flowmeter 13 (the flow is generally controlled at about 0.10L / min), the gaseous phase enters the analysis instrument 10 to carry out continuous real-time detection, and finally the gas after detection is discharged through the sample gas outlet pipeline 11, under the state of normal operation, the content of methane is ≤2500ppm, when the content of methane exceeds the threshold value, the following measures can be adopted: 1, improve the opening of the second valve 19, 2, improve the opening of the third valve 20, and reduce the opening of the fourth valve 21, 3, improve the opening of the first valve 18, the above three measures can be implemented simultaneously or individually to realize the reduction of the content of methane in the methane detection unit. Through the above setting, the accuracy of methane content detection can be ensured, thereby realizing the safe and stable operation of the heavy-removing rectifying tower 1.

[0031] The above only for the preferred embodiment of the utility model, but the protection scope of the utility model does not limit to this, any skilled in the art person in the utility model disclosed technical range, according to the utility model technical scheme and the utility model concept add up to equivalent replacement or change, all should be covered in the protection scope of the utility model.

Claims

1. A methane detection device used in a krypton-xenon liquid oxygen production system, characterized by, The detection device comprises a heavy-removing rectifying tower (1) in a liquid oxygen production system, a reboiler (2) connected with a heat source nitrogen pipeline in the heavy-removing rectifying tower (1), a detection pipeline and a tower bottom liquid discharge pipeline provided on the heavy-removing rectifying tower (1), the tower bottom liquid discharge pipeline being connected with a krypton-xenon concentrate storage tank (3) in a subsequent section, and the detection pipeline being connected with a methane detection unit through a gasification and uniform mixing unit.

2. The methane detection device for use in a krypton-xenon liquid oxygen production system according to claim 1, characterized in that, The gasification and uniform mixing unit at least comprises a water bath type vaporizer (4) and a gas phase uniform mixing assembly connected with the water bath type vaporizer (4).

3. The methane detection device for use in a krypton-xenon liquid oxygen production system according to claim 2, characterized in that, The gas phase uniform mixing assembly at least comprises a first buffer tank (5) and a second buffer tank (6) arranged in series, the inlet end of the first buffer tank (5) being connected with the outlet of the water bath type vaporizer (4), and the outlet end of the second buffer tank (6) being connected with the methane detection unit.

4. The methane detection device for use in a krypton-xenon liquid oxygen production system according to claim 3, characterized in that, The gas phase uniform mixing assembly further comprises a connecting pipeline (7) arranged between the outlet end of the second buffer tank (6) and the methane detection unit, and the length of the connecting pipeline (7) is 10-15 meters.

5. The methane detection device for use in a krypton-xenon liquid oxygen production system according to claim 4, characterized in that, The methane detection unit comprises an analysis panel (8), the inlet end of the analysis panel (8) being connected with the connecting pipeline, the outlet end of the analysis panel (8) being connected with an analysis instrument (10) through a filter (9), and a sample gas outlet pipeline (11) being arranged on the analysis instrument (10).

6. The methane detection device for use in a krypton-xenon liquid oxygen production system according to claim 5, characterized in that, An adjusting valve (12) and a flow meter (13) are arranged between the filter (9) and the analysis instrument (10).

7. The methane detection device for use in a krypton-xenon liquid oxygen production system according to claim 1, characterized in that, A liquid oxygen pipeline (14) with a first valve (18) is arranged on the heavy-removing rectifying tower (1).

8. The methane detection device for use in a krypton-xenon liquid oxygen production system according to claim 1, characterized in that, A second valve (19) is arranged on the tower bottom liquid discharge pipeline.

9. The methane detection device for use in a krypton-xenon liquid oxygen production system according to claim 1, characterized in that, A condenser (15) is arranged on the top of the heavy-removing rectifying tower (1), the liquid phase outlet of the condenser (15) being connected with a reflux tank (16), a third valve (20) being arranged between the outlet of the lower part of the reflux tank (16) and the reflux liquid inlet of the heavy-removing rectifying tower (1), and a fourth valve (21) being arranged between the outlet of the lower part of the reflux tank (16) and a liquid oxygen product tank (17).

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