CN216306724U - Sealing gas supply system for safe operation of liquid oxygen pump - Google Patents
Sealing gas supply system for safe operation of liquid oxygen pump Download PDFInfo
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- CN216306724U CN216306724U CN202122751959.7U CN202122751959U CN216306724U CN 216306724 U CN216306724 U CN 216306724U CN 202122751959 U CN202122751959 U CN 202122751959U CN 216306724 U CN216306724 U CN 216306724U
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- liquid oxygen
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- oxygen pump
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Abstract
The application provides a sealing gas supply system for safe operation of a liquid oxygen pump, which comprises an air separation molecular sieve, a nitrogen gas supply header pipe, the liquid oxygen pump, a booster first-stage meter-removing air storage tank, a first gas supply pipeline, a second gas supply pipeline and a third gas supply pipeline; the first gas supply pipeline is connected with a first-stage instrument-removing air storage tank of the supercharger, is used as a main sealing gas conveying pipeline and is connected with a sealing gas interface of the liquid oxygen pump, and is used for providing sealing gas for the liquid oxygen pump; the second gas supply pipeline is used as a standby sealing gas conveying pipeline and connected with a sealing gas interface of the liquid oxygen pump, the second gas supply pipeline is connected with the nitrogen gas supply main pipe, and the second gas supply pipeline is used for supplying standby sealing gas to the liquid oxygen pump; the air separation molecular sieve is communicated with a liquid outlet pipeline of the liquid oxygen pump through a third air supply pipeline and is used for providing heating air for the liquid oxygen pump. This application can obtain the enough and comparatively stable sealed gas of pressure, and then prevents that sealed gas pressure from taking place the phenomenon of liquid oxygen leakage inadequately.
Description
Technical Field
The application relates to sealed gas supply technical field, especially relates to a liquid oxygen pump safe operation is with sealed gas feed system.
Background
The air separation system is a set of industrial equipment for separating the component gases in the air to produce oxygen and nitrogen. The liquid oxygen pump is a cryogenic liquid pump, belongs to a component part in an air separation system, and realizes the transportation of liquid oxygen by improving the pressure of the liquid oxygen. The liquid oxygen pump of the air separation system generally uses dry and clean sealing gas with stable pressure to ensure the safe and stable operation of the equipment, and the sealing gas in the liquid oxygen pump can be used for preventing liquid from leaking and damaging the equipment, so that the reasonable supply of the sealing gas of the liquid oxygen pump is very important.
In the prior art, the sealing gas of the liquid oxygen pump is provided by a conveying pipeline from a molecular sieve of an air separation system, and because the sources of the sealing gas and the heating gas of the liquid oxygen pump in the prior art are both molecular sieves and the conveying of the sealing gas and the heating gas is the same pipeline, the pressure of the sealing gas of the liquid oxygen pump is easily too low, and therefore the flow of the sealing gas cannot be ensured. Because the sealing gas system in the prior art is unreasonable in design and causes low sealing gas pressure, low-temperature liquid leaks to generate frozen blockage, the problem that how to solve the low sealing gas pressure of the liquid oxygen pump is urgently needed to be solved.
SUMMERY OF THE UTILITY MODEL
The application provides a liquid oxygen pump safe operation is with sealed gas feed system for the sealed gas supply in-process of liquid oxygen pump appears sealed gas pressure easily among the solution prior art and hangs down and cause the problem of cryogenic liquids leakage.
The application provides a sealing gas supply system for safe operation of a liquid oxygen pump, which comprises an air separation molecular sieve, a nitrogen gas supply header pipe, the liquid oxygen pump, a booster first-stage instrument-removing air storage tank pipeline, a first gas supply pipeline, a second gas supply pipeline and a third gas supply pipeline;
the first gas supply pipeline is connected with a pipeline of the first section of the supercharger to the instrument-removing air storage tank, the first gas supply pipeline is used as a main sealing gas conveying pipeline and connected with a sealing gas interface of the liquid oxygen pump, and the first gas supply pipeline is used for providing sealing gas for the liquid oxygen pump;
the second gas supply pipeline is used as a standby sealed gas conveying pipeline and connected with a sealed gas interface of the liquid oxygen pump, the second gas supply pipeline is connected with the nitrogen gas supply main pipe, and the second gas supply pipeline is used for providing standby sealed gas for the liquid oxygen pump;
the air separation molecular sieve is communicated with a liquid outlet pipeline of the liquid oxygen pump through the third gas supply pipeline and is used for providing heating gas for the liquid oxygen pump.
In one possible implementation, the sealing form of the liquid oxygen pump adopts an inflation labyrinth type seal.
In a possible implementation manner, a first valve and a first pressure reducing valve are arranged on the first gas supply pipeline, a second valve and a second pressure reducing valve are arranged on the second gas supply pipeline, and a third valve is arranged on the third gas supply pipeline.
In a possible implementation manner, a first pressure gauge located behind the first pressure reducing valve is further arranged on the first gas supply pipeline, and the first pressure reducing valve is located between the first valve and the first pressure gauge; and a second pressure gauge behind the second pressure reducing valve is further arranged on the second gas supply pipeline, and the second pressure reducing valve is positioned between the second valve and the second pressure gauge.
In a possible implementation manner, the liquid oxygen pump further comprises a fourth gas supply pipeline and a blind plate, the fourth gas supply pipeline is connected with the third gas supply pipeline, the fourth gas supply pipeline is provided with a sealing gas interface which is used for cutting off the flowing direction of a gas source of the third gas supply pipeline to the blind plate, the fourth gas supply pipeline is further connected with the sealing gas interface of the liquid oxygen pump, and the first gas supply pipeline and the second gas supply pipeline are both connected to the fourth gas supply pipeline and pass through the fourth gas supply pipeline to the liquid oxygen pump provides sealing gas.
The application provides a sealing gas supply system for safe operation of a liquid oxygen pump, which comprises an air separation molecular sieve, a nitrogen gas supply header pipe, the liquid oxygen pump, a booster first-stage instrument-removing air storage tank pipeline, a first gas supply pipeline, a second gas supply pipeline and a third gas supply pipeline; the first gas supply pipeline is connected with a pipeline of the instrument-removing air storage tank at the first section of the supercharger, is used as a main sealing gas conveying pipeline and is connected with a sealing gas interface of the liquid oxygen pump, and is used for providing sealing gas for the liquid oxygen pump; the second gas supply pipeline is used as a standby sealing gas conveying pipeline and connected with a sealing gas interface of the liquid oxygen pump, the second gas supply pipeline is connected with the nitrogen gas supply main pipe, and the second gas supply pipeline is used for supplying standby sealing gas to the liquid oxygen pump; the air separation molecular sieve is communicated with a liquid outlet pipeline of the liquid oxygen pump through a third air supply pipeline and is used for providing heating air for the liquid oxygen pump.
In the application, by arranging the first air supply pipeline and connecting the first air supply pipeline with the pipeline of the supercharger for removing the instrument air storage tank, an air source from the pipeline of the supercharger for removing the instrument air storage tank can be connected into the liquid oxygen pump through the first air supply pipeline to be used as the sealing air of the independent liquid oxygen pump for supplying, so that the sealing air with enough pressure and stable stability can be obtained, and the phenomenon that the liquid oxygen leaks due to insufficient pressure of the sealing air is prevented; in addition, the second gas supply pipeline is arranged and connected with the nitrogen gas supply main pipe, so that the second gas supply pipeline can be used as spare sealing gas for supply, and particularly, when the air separation unit stops, the sealing gas of the liquid oxygen pump can be changed into the sealing gas which is prepared by decompressing the nitrogen gas provided by the nitrogen gas supply main pipe, so that the liquid oxygen leakage accident caused by the sealing gas breakage of the air separation unit is avoided; simultaneously this application can regard as the gas that heats of liquid oxygen pump with the air supply from empty molecular sieve through third gas supply line to prevent to produce the gas cross with the sealed gas that first gas supply line or second gas supply line provided.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a schematic diagram of a sealing gas supply method of a liquid oxygen pump in the prior art;
fig. 2 is a schematic composition diagram of a seal gas supply system for safe operation of a liquid oxygen pump according to an embodiment of the present disclosure;
fig. 3 is a schematic composition diagram of a seal gas supply system for safe operation of a liquid oxygen pump according to another embodiment of the present disclosure.
Description of reference numerals:
1. air separation molecular sieve, 2, liquid oxygen pump, 3, first gas supply pipeline, 4, second gas supply pipeline, 5, third gas supply pipeline, 6, nitrogen gas air supply house steward, 7, the booster compressor is one section to go to instrument air storage tank pipeline, 8, fourth gas supply pipeline, 9, the blind plate, 10, first valve, 11, first relief pressure valve, 12, the second valve, 13, the second relief pressure valve, 14, the third valve, 15, first manometer, 16, the second manometer.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application are clearly and completely described below, and it is obvious that the described embodiments are a part of the embodiments of the present application, but not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
FIG. 1 is a schematic diagram of a seal gas supply method of a liquid oxygen pump in the prior art. As shown in fig. 1, in the prior art, the sealing gas of the liquid oxygen pump is obtained from an air separation molecular sieve of an air separation unit, and the air separation molecular sieve simultaneously conveys the sealing gas and the warming gas to the liquid oxygen pump through a pipeline, which may cause the situation that the pressure of the sealing gas of the liquid oxygen pump is too low, thereby easily causing the leakage of low-temperature liquid oxygen and causing freezing blockage. In order to obtain the stable, higher air supply of quality of pressure as liquid oxygen pump seal gas air supply, the following improvement is made to this application.
Fig. 2 is a schematic composition diagram of a seal gas supply system for safe operation of a liquid oxygen pump according to an embodiment of the present application. As shown in fig. 2, the embodiment of the present application provides a seal gas supply system for safe operation of a liquid oxygen pump, which includes an air separation molecular sieve 1, a nitrogen gas supply header pipe 6, a liquid oxygen pump 2, a first-stage instrument-removing air storage tank pipeline 7 of a supercharger, a first gas supply pipeline 3, a second gas supply pipeline 4, and a third gas supply pipeline 5; the first gas supply pipeline 3 is connected with a pipeline 7 of the first section of the supercharger to the instrument air storage tank, the first gas supply pipeline 3 is used as a main sealing gas conveying pipeline and connected with a sealing gas interface of the liquid oxygen pump 2, and the first gas supply pipeline 3 is used for supplying sealing gas to the liquid oxygen pump 2; the second gas supply pipeline 4 is used as a standby sealed gas conveying pipeline and connected with a sealed gas interface of the liquid oxygen pump 2, the second gas supply pipeline 4 is connected with a nitrogen gas supply header 6, and the second gas supply pipeline 4 is used for supplying standby sealed gas to the liquid oxygen pump 2; the air separation molecular sieve 1 is communicated with a liquid outlet pipeline of the liquid oxygen pump 2 through a third gas supply pipeline 5 and is used for providing heating gas for the liquid oxygen pump 2. The air supply pressure of one section of the booster to the instrument air storage tank pipeline 7 and the nitrogen gas supply main pipe 6 in the air-enriched separation system can meet the use requirement of the sealing gas of the liquid oxygen pump, and the air supply is pure and can supply the sealing gas to the liquid oxygen pump after the pressure is adjusted.
According to the sealing gas supply system for the safe operation of the liquid oxygen pump, the first gas supply pipeline 3 is arranged, the first gas supply pipeline 3 is connected with the first section of the booster to the instrument air storage tank pipeline 7, and the gas source from the first section of the booster to the instrument air storage tank pipeline 7 is connected into the liquid oxygen pump 2 through the first gas supply pipeline 3 to be used as the sealing gas of the independent liquid oxygen pump for supply, so that the sealing gas with enough pressure and stable pressure can be obtained, and the phenomenon that the liquid oxygen leaks due to the fact that the pressure of the sealing gas is not enough is prevented; in addition, the second gas supply pipeline 4 is arranged, the second gas supply pipeline 4 is connected with the nitrogen gas supply main pipe 6, the second gas supply pipeline 4 can be used as spare sealing gas for supply, specifically, when the air separation unit stops, the sealing gas of the liquid oxygen pump can be changed into the sealing gas of nitrogen gas provided by the nitrogen gas supply main pipe 6 after being decompressed, and the liquid oxygen leakage accident caused by the sealing gas breaking of the air separation unit is avoided; simultaneously this application is through third gas supply line 5, can only regard as the gas that heats of liquid oxygen pump 2 with the air supply from empty molecular sieve 1 of dividing to prevent to cross the gas with the sealed gas that first gas supply line 3 or second gas supply line 4 provided.
In the embodiment of the application, the pressure of the sealing gas in the first gas supply pipeline 3 and the second gas supply pipeline 4 is 0.7MPa when the sealing gas is supplied to the liquid oxygen pump 2, and the sealing gas pressure can be increased by adopting the sealing gas pressure design, so that the liquid oxygen is prevented from leaking due to insufficient sealing gas pressure. And first gas supply pipeline 3 alone supplies the seal gas to the liquid oxygen pump, can avoid the pressure of seal gas not enough. Alternatively, the sealing form of the liquid oxygen pump 2 employs a gas-filled labyrinth seal.
In the specific application, the liquid oxygen pump 2 adopts a frequency converter to control the rotating speed, the liquid oxygen pump 2 adopts an inflatable labyrinth seal mode, and a strand of gas can be led out from the inlet side of the inducer of the liquid oxygen pump to serve as a reference gas of the sealing gas of the liquid oxygen pump, so that the sealing gas with the pressure higher than that of the reference gas can be conveniently provided according to the pressure of the reference gas. The gas-filled labyrinth seal is a sealing manner which utilizes a labyrinth-type structure and introduces sealing gas into the labyrinth-type structure so as to prevent low-temperature liquid from leaking along a pump shaft. The purpose of introducing the sealing gas into the liquid oxygen pump is to reduce the leakage of low-temperature liquid and prevent the motor bearing from being damaged at low temperature. But the pressure of the sealing gas cannot be too high, so that the gas is prevented from entering the pump body through the labyrinth seal to form cavitation. Therefore, the pressure of the seal gas was 0.7MPa in the examples of the present application.
As an optional mode of the embodiment of the present application, the first air supply pipeline 3 is provided with a first valve 10 and a first pressure reducing valve 11, the second air supply pipeline 4 is provided with a second valve 12 and a second pressure reducing valve 13, and the third air supply pipeline 5 is provided with a third valve 14.
In the normal use process, the first valve 10 on the first gas supply pipeline 3 and the third valve 14 on the third gas supply pipeline 5 are opened, the second valve 12 on the second gas supply pipeline 4 is closed, the first pressure reducing valve 11 is adjusted, so that the gas source pressure in the first gas supply pipeline 3 is adjusted to 0.7MPa, and the gas source pressure is connected into the liquid oxygen pump as the sealing gas of the liquid oxygen pump. When the air separation unit needs to stop, the sealing gas of the liquid oxygen pump can be changed into the sealing gas provided by the second gas supply pipeline 4 to the liquid oxygen pump, a user can open the second valve 12 on the second gas supply pipeline 4 and adjust the second pressure reducing valve 13 to adjust the gas source pressure in the second gas supply pipeline 4 to 0.7MPa, the sealing gas serving as the standby sealing gas of the liquid oxygen pump is connected into the liquid oxygen pump, and the liquid oxygen leakage accident caused by the sealing gas cut of the air separation unit is avoided.
As an optional mode of the embodiment of the application, the first gas supply pipeline 3 is further provided with a first pressure gauge 15 located behind the first pressure reducing valve 11, and the first pressure reducing valve 11 is located between the first valve 10 and the first pressure gauge 15; a second pressure gauge 16 is further arranged on the second gas supply pipeline 4 and behind the second pressure reducing valve 13, and the second pressure reducing valve 13 is arranged between the second valve 12 and the second pressure gauge 16. In the embodiment of the application, the sealing air pressure can be conveniently observed by arranging the first pressure gauge 15 and the second pressure gauge 16, so that the sealing air pressure can be adjusted as required.
As an optional mode of the embodiment of the present application, as shown in fig. 3, the sealing gas supply system for safe operation of a liquid oxygen pump provided in the embodiment of the present application further includes a fourth gas supply pipeline 8 and a blind plate 9, the fourth gas supply pipeline 8 is connected to the third gas supply pipeline 5, the blind plate 9 for blocking the flow direction of the gas source of the third gas supply pipeline 5 is provided on the fourth gas supply pipeline 8, the fourth gas supply pipeline 8 is further connected to a sealing gas interface of the liquid oxygen pump 2, and the first gas supply pipeline 3 and the second gas supply pipeline 4 are both connected to the fourth gas supply pipeline 8 and provide sealing gas to the liquid oxygen pump 2 through the fourth gas supply pipeline 8. In the embodiment of the application, the fourth gas supply pipeline 8 and the blind plate 9 are arranged, the first gas supply pipeline 3 and the second gas supply pipeline 4 are connected to the fourth gas supply pipeline 8, and the sealing gas is provided for the liquid oxygen pump 2 through the fourth gas supply pipeline 8, so that the improvement can be conveniently carried out on the basis of the prior art that the air separation molecular sieve is adopted to provide the sealing gas for the liquid oxygen pump through a pipeline, on the basis of not changing the existing pipeline system of the original air separation molecular sieve for providing sealing gas and heating gas for the liquid oxygen pump, the original air source serving as the sealing air from the air separation molecular sieve is plugged outside the liquid oxygen pump through the blind plate 9 on the fourth air supply pipeline 8, and then the air source with stable pressure and high quality is provided for the liquid oxygen pump through the first air supply pipeline 3 to serve as the sealing air of the liquid oxygen pump, and the air source serves as the air supply pipeline for providing the standby sealing air through the second air supply pipeline 4. After the mode is adopted for transformation, the operation of the liquid oxygen pump is stable, the phenomenon of accidental vehicle jumping of the liquid oxygen pump caused by the pressure reduction of the sealing gas is avoided, and the long-period stable operation of the air separation equipment is ensured.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art; the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present application.
Claims (5)
1. A sealed gas supply system for safe operation of a liquid oxygen pump is characterized by comprising an air separation molecular sieve, a nitrogen gas supply header pipe, the liquid oxygen pump, a booster first-stage instrument-removing air storage tank pipeline, a first gas supply pipeline, a second gas supply pipeline and a third gas supply pipeline;
the first gas supply pipeline is connected with a pipeline of the first section of the supercharger to the instrument-removing air storage tank, the first gas supply pipeline is used as a main sealing gas conveying pipeline and connected with a sealing gas interface of the liquid oxygen pump, and the first gas supply pipeline is used for providing sealing gas for the liquid oxygen pump;
the second gas supply pipeline is used as a standby sealed gas conveying pipeline and connected with a sealed gas interface of the liquid oxygen pump, the second gas supply pipeline is connected with the nitrogen gas supply main pipe, and the second gas supply pipeline is used for providing standby sealed gas for the liquid oxygen pump;
the air separation molecular sieve is communicated with a liquid outlet pipeline of the liquid oxygen pump through the third gas supply pipeline and is used for providing heating gas for the liquid oxygen pump.
2. The seal gas supply system for the safe operation of a liquid oxygen pump according to claim 1, wherein the seal form of the liquid oxygen pump employs a gas-filled labyrinth seal.
3. The seal gas supply system for the safe operation of a liquid oxygen pump according to claim 1, wherein the first gas supply line is provided with a first valve and a first pressure reducing valve, the second gas supply line is provided with a second valve and a second pressure reducing valve, and the third gas supply line is provided with a third valve.
4. The seal gas supply system for the safe operation of the liquid oxygen pump according to claim 3, wherein a first pressure gauge is further disposed on the first gas supply pipeline after the first pressure reducing valve, and the first pressure reducing valve is disposed between the first valve and the first pressure gauge; and a second pressure gauge behind the second pressure reducing valve is further arranged on the second gas supply pipeline, and the second pressure reducing valve is positioned between the second valve and the second pressure gauge.
5. The system for supplying sealing gas for the safe operation of liquid oxygen pump according to any one of claims 1 to 4, further comprising a fourth gas supply pipeline and a blind plate, wherein the fourth gas supply pipeline is connected with the third gas supply pipeline, the blind plate for isolating the gas source flowing direction of the third gas supply pipeline is arranged on the fourth gas supply pipeline, the fourth gas supply pipeline is further connected with the sealing gas interface of the liquid oxygen pump, and the first gas supply pipeline and the second gas supply pipeline are connected to the fourth gas supply pipeline and provide sealing gas for the liquid oxygen pump through the fourth gas supply pipeline.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122751959.7U CN216306724U (en) | 2021-11-11 | 2021-11-11 | Sealing gas supply system for safe operation of liquid oxygen pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122751959.7U CN216306724U (en) | 2021-11-11 | 2021-11-11 | Sealing gas supply system for safe operation of liquid oxygen pump |
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| Publication Number | Publication Date |
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| CN216306724U true CN216306724U (en) | 2022-04-15 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202122751959.7U Active CN216306724U (en) | 2021-11-11 | 2021-11-11 | Sealing gas supply system for safe operation of liquid oxygen pump |
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| CN (1) | CN216306724U (en) |
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2021
- 2021-11-11 CN CN202122751959.7U patent/CN216306724U/en active Active
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