Nitrogen purging source system of gas turbine power plant

Abstract

The utility model belongs to the field of gas turbines, and provides a gas turbine power plant nitrogen purging source system which comprises a nitrogen cylinder set, a nitrogen storage tank, a nitrogen input mother pipe, a nitrogen output pipeline, a safety valve exhaust pipeline and a blow-off pipeline. The nitrogen cylinder group is communicated with a nitrogen storage tank through a nitrogen input mother pipe; a first ball valve, a first filter, a first manual pressure reducing valve and a second ball valve are sequentially arranged on the nitrogen input main pipe; one end of the nitrogen output pipeline is communicated with the nitrogen storage tank, and the other end is communicated with the gas turbine; the safety valve exhaust pipeline is arranged at the top of the nitrogen storage tank; and the blow-off pipeline is arranged at the bottom of the nitrogen storage tank, so that the operation stability of the gas turbine unit can be improved.

Description

Technical Field

[0001] The utility model belongs to the field of gas turbines, and in particular relates to a nitrogen purge source system for a gas turbine power plant. Background Art

[0002] The statements in this section merely provide background technical information related to the present invention and do not necessarily constitute prior art.

[0003] When the gas turbine (hereinafter referred to as the gas turbine) fails to ignite or the combustion mode is switched, the natural gas pipeline needs to be purged and cooled, that is, the natural gas remaining in the pipeline needs to be purged and cooled. The existing technology uses air to purge and cool the natural gas pipeline, that is, the natural gas in the pipeline is purged clean by air purge. After the natural gas is purged clean, the air needs to be continuously passed to cool the natural gas pipeline. However, the explosion limit range of natural gas is 5%-15%. That is, when the natural gas concentration drops to 5%-15% when air is used to purge the natural gas, it will explode when it encounters an open flame, which poses a safety hazard.

[0004] In order to solve the above-mentioned drawbacks, nitrogen purge is adopted to purge the natural gas pipeline. However, in the prior art, the nitrogen cylinder is directly used to purge the downstream pipelines and equipment after the pressure is reduced by the pressure reducing valve. There is a possibility of pressure reduction failure of the pressure reducing valve. If the pressure reducing valve fails, the high-pressure nitrogen directly enters the downstream pipelines and equipment, which will cause damage to the pipelines and equipment. Utility Model Content

[0005] In order to solve the technical problems existing in the above-mentioned background technology, the utility model provides a nitrogen purge source system for a gas turbine power plant, which can improve the operating stability of the gas turbine unit.

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

[0007] A nitrogen purge source system for a gas turbine power plant, comprising:

[0008] Nitrogen cylinder group, nitrogen storage tank, nitrogen input main pipe, nitrogen output pipeline, safety valve exhaust pipeline and sewage pipeline;

[0009] The nitrogen cylinder group is connected to the nitrogen storage tank through the nitrogen input main pipe;

[0010] The nitrogen input main pipe is provided with a first ball valve, a first filter, a first manual pressure reducing valve and a second ball valve in sequence;

[0011] One end of the nitrogen output pipeline is connected to the nitrogen storage tank, and the other end is connected to the gas turbine;

[0012] The safety valve exhaust pipe is arranged on the top of the nitrogen storage tank;

[0013] The sewage discharge pipe is arranged at the bottom of the nitrogen storage tank.

[0014] As an implementation manner, the first manual pressure reducing valve is also arranged in parallel with the second manual pressure reducing valve.

[0015] As an implementation mode, the first manual pressure reducing valve and the second manual pressure reducing valve are both used as a backup valve.

[0016] As an implementation manner, manual ball valves are respectively connected in series at both ends of the first manual pressure-reducing valve and the second manual pressure-reducing valve.

[0017] As an implementation mode, the outlet of each nitrogen cylinder in the nitrogen cylinder group is connected to the nitrogen input main pipe in sequence through a third ball valve and a check valve.

[0018] As an implementation manner, the safety valve exhaust pipe is formed by the convergence of a first exhaust branch and a second exhaust branch.

[0019] As an implementation mode, the first exhaust branch is connected to the nitrogen storage tank through a fourth ball valve.

[0020] As an implementation mode, the second exhaust branch is connected to the nitrogen storage tank through a safety valve.

[0021] As an implementation manner, there is at least one sewage valve on the sewage pipe.

[0022] As an implementation mode, the nitrogen output pipeline is connected to the gas engine through a second filter and a fifth ball valve in sequence.

[0023] The beneficial effects of the utility model are:

[0024] (1) The nitrogen purge source system of the gas turbine power plant of the utility model introduces a nitrogen storage tank. First, the high-pressure nitrogen in the nitrogen bottle is used to fill the nitrogen storage tank with nitrogen to a preset pressure. During the process of filling the nitrogen storage tank with nitrogen, the valve of the nitrogen pipeline from the nitrogen storage tank outlet to the gas turbine is closed. Even if the pressure reducing valve fails during the nitrogen filling process, the high-pressure nitrogen will not enter the downstream gas turbine and will not damage the downstream equipment and pipelines. The over-pressure nitrogen is discharged into the air through the safety valve of the nitrogen storage tank.

[0025] (2) The utility model provides a first manual pressure reducing valve and a second manual pressure reducing valve in parallel on the nitrogen input main pipe. The first manual pressure reducing valve and the second manual pressure reducing valve are used as a backup valve. If the pressure reducing valve fails during use, the isolation ball valves before and after the pressure reducing valve are closed, the pressure reducing valve can be removed for maintenance, and the backup pressure reducing valve can be used to work, thereby improving the reliability of the system.

[0026] Advantages of additional aspects of the present invention will be partially given in the following description, and partially become apparent from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention.

[0028] Figure 1 It is a structural schematic diagram of a nitrogen purge source system for a gas turbine power plant according to an embodiment of the utility model.

[0029] Among them, 1. Nitrogen cylinder group; 2. Nitrogen input main pipe; 3. Nitrogen storage tank; 4. Nitrogen output pipeline; 5. Gas turbine; 6. Safety valve exhaust pipeline; 7. First ball valve; 8. First filter; 9. First manual pressure reducing valve; 10. Second manual pressure reducing valve; 11. Second ball valve; 12. Third ball valve; 13. Check valve; 14. Second filter; 15. Fifth ball valve; 16. Fourth ball valve; 17. Safety valve; 18. Sewage pipeline; 19. Sewage valve; 20. Manual ball valve. DETAILED DESCRIPTION

[0030] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0031] It should be noted that the following detailed descriptions are all exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0032] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the utility model. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0033] Terminology explanation:

[0034] Gas engine: It is the abbreviation of gas turbine, which is a device that burns natural gas to drive the impeller to rotate at high speed and output power.

[0035] according to Figure 1A nitrogen purge source system for a gas turbine power plant in this embodiment comprises: a nitrogen bottle group 1, a nitrogen storage tank 3, a nitrogen input mother pipe 2, a nitrogen output pipeline 4, a safety valve exhaust pipeline 6 and a sewage pipeline 18; the nitrogen bottle group 1 is connected to the nitrogen storage tank 3 through the nitrogen input mother pipe 2; the nitrogen input mother pipe 2 is sequentially provided with a first ball valve 7, a first filter 8, a first manual pressure reducing valve 9 and a second ball valve 11; one end of the nitrogen output pipeline 4 is connected to the nitrogen storage tank 3, and the other end is connected to the gas turbine 5; the safety valve exhaust pipeline 6 is arranged at the top of the nitrogen storage tank 3; the sewage pipeline 18 is arranged at the bottom of the nitrogen storage tank 3.

[0036] In this embodiment, the first manual pressure reducing valve 9 is also arranged in parallel with the second manual pressure reducing valve 10. The first manual pressure reducing valve 9 and the second manual pressure reducing valve 10 are both used as a backup.

[0037] Among them, the first manual pressure reducing valve 9 and the second manual pressure reducing valve 10 are respectively connected in series with manual ball valves 20. The manual ball valve 20 is used for isolation. For example, when the first manual pressure reducing valve 9 needs to be removed for maintenance, the ball valves before and after the first manual pressure reducing valve 9 are closed before the first manual pressure reducing valve 9 can be removed.

[0038] In this embodiment, a first manual pressure reducing valve and a second manual pressure reducing valve are arranged in parallel on the nitrogen input mother pipe. The first manual pressure reducing valve and the second manual pressure reducing valve are used as a backup valve. If the pressure reducing valve fails during use, the isolation ball valves before and after the pressure reducing valve are closed, the pressure reducing valve can be removed for maintenance, and the backup pressure reducing valve can be used to work, thereby improving the reliability of the system.

[0039] In some specific implementation processes, the number of nitrogen cylinder groups can be selected according to actual conditions, such as 30 nitrogen cylinder groups, each nitrogen cylinder has a volume of 40L and a pressure resistance of P=15MPa.

[0040] In this embodiment, the outlet of each nitrogen cylinder in the nitrogen cylinder group 1 is connected to the nitrogen input main pipe 2 through the third ball valve 12 and the check valve 13 in sequence.

[0041] In this embodiment, taking the nitrogen storage tank with a volume of 2m3 and a withstand pressure of P=5MPa as an example, the nitrogen storage tank is first filled with nitrogen during operation, and the third ball valve at the outlet of the nitrogen bottle is opened in sequence. The nitrogen with a pressure of 15MPa in the cylinder enters the nitrogen storage tank after being reduced in pressure by the first manual pressure reducing valve or the second manual pressure reducing valve. When the pressure in the nitrogen storage tank reaches 5MPa, the third ball valve at the outlet of the nitrogen bottle is closed to complete one-time nitrogen filling.

[0042] In this embodiment, the nitrogen output pipeline 4 is connected to the engine 5 through the second filter 14 and the fifth ball valve 15 in sequence. The fifth ball valve at the outlet of the nitrogen storage tank is opened to provide purge nitrogen to the engine, and the supply of purge nitrogen to the engine is stopped when the pressure of the nitrogen storage tank drops to 4MPa. The ball valve at the outlet of the nitrogen bottle is opened again to inflate the nitrogen storage tank. When the pressure of the nitrogen bottle is reduced and the nitrogen storage tank cannot be inflated with nitrogen, the nitrogen bottle is replaced.

[0043] In this embodiment, the safety valve exhaust pipe 6 is formed by the first exhaust branch and the second exhaust branch. The first exhaust branch is connected to the nitrogen storage tank 3 through the fourth ball valve 16. The second exhaust branch is connected to the nitrogen storage tank 3 through the safety valve 17. If the nitrogen storage tank is over-pressured, it is discharged through the safety valve on the top of the storage tank. The safety valve exhaust pipe is discharged to the air.

[0044] In this embodiment, the sewage pipe 18 is provided with at least one sewage valve 19 for discharging the water accumulated in the storage tank 3. The sewage pipe 18 is connected to a channel or a temporary water bucket.

[0045] The nitrogen purge source system of the gas turbine power plant in this embodiment introduces a nitrogen storage tank. First, the high-pressure nitrogen in the nitrogen bottle is used to fill the nitrogen storage tank with nitrogen, and the pressure of the nitrogen storage tank is filled to a preset pressure. During the process of filling the nitrogen storage tank with nitrogen, the valve of the nitrogen pipeline from the nitrogen storage tank outlet to the gas turbine is closed. Even if the pressure reducing valve fails during the nitrogen filling process, the high-pressure nitrogen will not enter the downstream gas turbine and will not damage the downstream equipment and pipelines. The over-pressure nitrogen is discharged into the air through the safety valve of the nitrogen storage tank.

[0046] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A nitrogen purge source system for a gas turbine power plant, characterized in that: include: Nitrogen cylinder group, nitrogen storage tank, nitrogen input main pipe, nitrogen output pipeline, safety valve exhaust pipeline and sewage pipeline; The nitrogen cylinder group is connected to the nitrogen storage tank through the nitrogen input main pipe; The nitrogen input main pipe is provided with a first ball valve, a first filter, a first manual pressure reducing valve and a second ball valve in sequence; One end of the nitrogen output pipeline is connected to the nitrogen storage tank, and the other end is connected to the gas turbine; The safety valve exhaust pipe is arranged on the top of the nitrogen storage tank; The sewage discharge pipe is arranged at the bottom of the nitrogen storage tank.

2. The nitrogen purge source system for a gas turbine power plant according to claim 1, characterized in that: The first manual pressure reducing valve is also arranged in parallel with the second manual pressure reducing valve.

3. The nitrogen purge source system for a gas turbine power plant according to claim 2, characterized in that: The first manual pressure reducing valve and the second manual pressure reducing valve are used as a backup valve.

4. The nitrogen purge source system for a gas turbine power plant according to claim 2, characterized in that: Manual ball valves are respectively connected in series at both ends of the first manual pressure reducing valve and the second manual pressure reducing valve.

5. The nitrogen purge source system for a gas turbine power plant according to claim 1, characterized in that: The outlet of each nitrogen cylinder in the nitrogen cylinder group is connected to the nitrogen input main pipe through the third ball valve and the check valve in sequence.

6. The nitrogen purge source system for a gas turbine power plant according to claim 1, characterized in that: The safety valve exhaust pipeline is formed by the convergence of a first exhaust branch and a second exhaust branch.

7. The nitrogen purge source system for a gas turbine power plant according to claim 6, characterized in that: The first exhaust branch is connected to the nitrogen storage tank through a fourth ball valve.

8. The nitrogen purge source system for a gas turbine power plant according to claim 6, characterized in that: The second exhaust branch is connected to the nitrogen storage tank through a safety valve.

9. The nitrogen purge source system for a gas turbine power plant according to claim 1, characterized in that: The sewage pipe is provided with at least one sewage valve.

10. The nitrogen purge source system for a gas turbine power plant according to claim 1, characterized in that: The nitrogen output pipeline is connected to the combustion engine through the second filter and the fifth ball valve in sequence.

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