Natural gas junction station pipe network blowdown system

Abstract

The utility model relates to a natural gas junction station pipe network pollution discharge system, which belongs to the field of natural gas pipe network pollution discharge and comprises an in-use separation branch and a standby separation branch. The in-use separation branch comprises a first separator connected with the main pipe network, a gas outlet of the first separator is connected with a second separator, a pollution discharge outlet of the first separator is connected to a pollution discharge pool through a pollution discharge pipe, and when desilting is needed, pressure difference pressure relief on the in-use separation branch is equalized to the standby separation branch in a balanced mode; by means of switching of the standby separation branch, the problems of emptying waste and low efficiency in the cleaning process of the pipe network with the separation branch are solved, the standby separation branch can be balanced through emptying pressure, sudden change of the pressure difference in the pipe network is reduced, meanwhile, the gas conveying efficiency of the pipe network is improved, excessive resource waste caused by emptying is avoided, and the energy consumption is reduced. The main blow-down valve is additionally arranged at the main blow-down pipe, the main blow-down valve is closed in the desilting process, the dual-protection effect is achieved, and therefore the desilting operation is conducted safely and stably.

Description

Technical Field

[0001] The utility model belongs to the field of sewage discharge of natural gas pipeline networks, and particularly relates to a sewage discharge system for a natural gas hub pipeline network. Background Art

[0002] With the increase in the laying of rural natural gas pipeline networks, it is necessary to use gas hubs for the separation, dust removal, pressure regulation, metering, and pigging of the incoming gas from each branch line, and to undertake the transmission and distribution work for downstream users. For gas hubs with a large volume of incoming gas, the load of the separators for separation and dust removal is large, and sewage discharge must be carried out regularly every week to ensure the normal processing capacity of the separators; currently, before each sewage discharge, it is necessary to first carry out venting, and then carry out sewage discharge after the pressure drops below 0.5 mpa. For a three-line gas transmission design pressure of 8.0 mpa and a maximum operating pressure of up to 7.6 ma, depending on the incoming station pressure, the venting volume can reach hundreds of standard cubic meters, greatly reducing the pipeline transportation efficiency and increasing the transmission difference, not only increasing the cleaning cost, but also increasing the risk of pipeline cleaning. Content of the Utility Model

[0003] The purpose of the utility model is to provide a sewage discharge system for a natural gas hub pipeline network, so as to overcome the low exhaust efficiency and large resource waste of the existing single-pipe exhaust for sewage discharge of natural gas hub pipeline networks.

[0004] A sewage discharge system for a natural gas hub pipeline network includes an in-use separation branch and a standby separation branch;

[0005] The in-use separation branch includes a first separator connected to the main pipeline network. The gas outlet of the first separator is connected to a second separator. The sewage discharge outlet of the first separator is connected to a sewage discharge tank through a sewage discharge pipe; a venting port is provided on the second separator and is connected to a venting area through a venting pipeline. A first gate valve and a first venting valve are sequentially arranged on the venting pipeline; an exhaust port is provided on the second separator, and the exhaust port on the second separator is connected to an exhaust pipe network through a first exhaust pipe. A first ball valve is arranged on the first exhaust pipe;

[0006] The standby separation branch includes a third separator connected to the main pipeline network. The gas outlet of the third separator is connected to a fourth separator. The sewage discharge outlet of the third separator is connected to a sewage discharge tank through a sewage discharge pipe; a venting port is provided on the fourth separator and is communicated with the venting pipeline of the second separator through a venting pipe. A second gate valve and a second venting valve are sequentially arranged on the venting pipe. The end of the second venting valve is communicated with the end of the first venting valve, and a third venting valve is arranged at the end of the venting pipeline; an exhaust port is provided on the fourth separator, and the exhaust port on the fourth separator is connected to an exhaust pipe network through a second exhaust pipe. A second ball valve is arranged on the second exhaust pipe.

[0007] Preferably, both the third separator and the first separator adopt cyclone separators.

[0008] Preferably, both the fourth separator and the second separator adopt filter separators.

[0009] Preferably, both the first vent valve and the second vent valve adopt throttle valves.

[0010] Preferably, a first stop valve and a first blowdown valve are arranged on the pipeline connected to the blowdown port of the first separator.

[0011] Preferably, a blowdown port is arranged at the bottom of the second separator, and a second stop valve and a second blowdown valve are arranged on the pipeline connected to the blowdown port of the second separator.

[0012] Preferably, a third stop valve and a third blowdown valve are arranged on the pipeline connected to the blowdown port of the third separator.

[0013] Preferably, a blowdown port is arranged at the bottom of the fourth separator, and a fourth stop valve and a fourth blowdown valve are arranged on the pipeline connected to the blowdown port of the fourth separator.

[0014] Preferably, the pipelines connected to the blowdown ports of the first separator, the second separator, the third separator and the fourth separator are connected to the main blowdown pipe, and a main blowdown valve is arranged on the main blowdown pipe.

[0015] Preferably, the first blowdown valve, the second blowdown valve and the third blowdown valve all adopt sleeve type blowdown valves. Compared with the prior art, the utility model has the following beneficial technical effects:

[0016] For a natural gas hub station pipe network blowdown system of the utility model, a standby separation branch is connected in parallel with an in-use separation branch. The standby separation branch serves as a standby pipeline for the in-use separation branch and is used as a standby pipe during the silt cleaning process of the in-use separation branch. When silt cleaning is required, the pressure difference on the in-use separation branch is equalized to the standby separation branch in an equalizing manner. By using the standby separation branch for switching, it avoids the problems of waste during venting and low efficiency during the cleaning process of the in-use separation branch pipe network. The standby separation branch can be equalized by the venting pressure, reducing the sudden change of the pressure difference in the pipe network. At the same time, it improves the gas transmission efficiency of the pipe network and avoids excessive waste of resources caused by venting.

[0017] A main blowdown valve is added at the main blowdown pipe. During the silt cleaning process, the main blowdown valve is closed, playing a dual protection role, so that the silt cleaning operation can be carried out safely and smoothly. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of the natural gas hub station pipe network blowdown system in the embodiment of the utility model.

[0019] In the figure, 1 is the first separator; 2 is the second separator; 3 is the sewage discharge pit; 4 is the vent pipe; 5 is the third separator; 6 is the fourth separator; 7 is the vent tube; 8 is the first gate valve; 9 is the first vent valve; 10 is the second gate valve; 11 is the second vent valve; 12 is the third vent valve; 13 is the first exhaust pipe; 14 is the first ball valve; 15 is the second exhaust pipe; 16 is the second ball valve; 17 is the first globe valve; 18 is the first sewage discharge valve; 19 is the second globe valve; 20 is the second sewage discharge valve; 21 is the third globe valve; 22 is the third sewage discharge valve; 23 is the fourth globe valve; 24 is the fourth sewage discharge valve; 25 is the main sewage discharge valve; 26 is the third ball valve; 110 is the in-use separation branch; 220 is the standby separation branch. Detailed implementation manners

[0020] In order to enable those skilled in the art of this technology to better understand the solution of the present utility model, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present utility model.

[0021] It should be noted that the terms "first", "second", etc. in the description and claims of the present utility model and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present utility model described herein can be implemented in an order different from those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0022] As Figure 1 shown, a sewage discharge system for a natural gas hub station pipe network includes an in-use separation branch 110 and a standby separation branch 220;

[0023] When the separation branch 110 is used as a common separation pipeline of a gas transmission pipeline network, it includes a first separator 1 connected to the main pipeline network. The gas outlet of the first separator 1 is connected to a second separator 2, and the sewage discharge outlet of the first separator 1 is connected to a sewage pool 3 through a sewage pipe. The gas outlet of the first separator 1 is arranged at the upper end of the first separator 1, and its sewage discharge port is arranged at the lower end of the first separator 1. A venting port is arranged on the second separator 2 and is connected to a venting area through a venting pipeline 4. A first gate valve 8 and a first venting valve 9 are sequentially arranged on the venting pipeline 4, which are used to vent and depressurize the first separator 1 and the second separator 2 on the in-use separation branch 110, so as to facilitate the subsequent silt cleaning treatment of the in-use separation branch 110. An exhaust port is arranged on the second separator 2, and the exhaust port on the second separator 2 is connected to an exhaust pipeline network through a first exhaust pipe 13. A first ball valve 14 is arranged on the first exhaust pipe 13 to control the discharge of the filtered gas of the second separator 2 of the in-use separation branch 110 by using the first ball valve 14.

[0024] The standby separation branch 220 serves as a standby pipeline for the in-use separation branch 110 and is used as a standby pipe during the silt cleaning process of the in-use separation branch 110 to improve the gas transmission efficiency of the pipeline network and avoid the shutdown of the pipeline network due to silt cleaning. Multiple groups of in-use separation branches 110 are simultaneously arranged in the gas hub station for different main line gas transmissions; the standby separation branch 220 can be connected in parallel to each in-use separation branch 110, or a group of standby separation branches 220 can be arranged on each in-use separation branch 110;

[0025] The standby separation branch 220 has the same structure as the in-use separation branch 110 and includes a third separator 5 connected to the main pipeline network. The gas outlet of the third separator 5 is connected to a fourth separator 6, and the sewage discharge outlet of the third separator 5 is connected to a sewage pool 3 through a sewage pipe. The third separator 5 has the same structure as the first separator 1, and both adopt a cyclone separator for the preliminary filtration of gas; the fourth separator 6 has the same structure as the second separator 2, and both adopt a filter separator for the purification and impurity removal of gas; the venting port of the fourth separator 6 is communicated with the venting pipeline 4 of the second separator 2 through a venting pipe 7. A second gate valve 10 and a second venting valve 11 are sequentially arranged on the venting pipe 7. The end of the second venting valve 11 is communicated with the end of the first venting valve 9, and a third venting valve 12 is arranged at the end of the venting pipeline 4; the fourth separator 6 is provided with an exhaust port, and the exhaust port on the fourth separator 6 is connected to an exhaust pipeline network through a second exhaust pipe 15. A second ball valve 16 is arranged on the second exhaust pipe 15 to control the discharge of the filtered gas of the fourth separator 6 of the standby separation branch 220 by using the second ball valve 16.

[0026] Both the first venting valve 9 and the second venting valve 11 adopt throttle valves.

[0027] In use, the first ball valve 14 on the first exhaust pipe 13 of the second separator 2 is closed, and the second ball valve 16 on the second exhaust pipe 15 of the fourth separator 6 is closed; the first gate valve 8 and the first vent valve 9 are both opened, the third vent valve 12 is closed, the second gate valve 10 and the second vent valve 11 are both opened. At this time, the in-use separation branch 110 and the standby separation branch 220 are connected, and the pressure of the in-use separation branch 110 can be equalized with that of the standby separation branch 220. After the pressures of the in-use separation branch 110 and the standby separation branch 220 are equalized, the second gate valve 10 and the second vent valve 11 are closed, and the third vent valve 12 at the end of the vent pipe 4 is opened. At this time, the in-use separation branch 110 is vented and depressurized to 0.5 mpa for subsequent sewage discharge operations; the second ball valve 16 on the second exhaust pipe 15 is opened to enable the standby separation branch 220 to filter the gas; after the in-use separation branch 110 is cleared of silt, the standby separation branch 220 can be switched to the in-use separation branch 110 using the same steps, and the standby separation branch 220 can be cyclically used to switch and clear the silt of other in-use separation branches 110 connected to the standby separation branch 220, realizing the switching and silt cleaning work of different in-use separation branches 110.

[0028] This application uses the standby separation branch 220 to be connected in parallel with the in-use separation branch 110. When silt cleaning is required, the pressure difference on the in-use separation branch 110 is depressurized and equalized to the standby separation branch 220 in an equalizing manner. By using the standby separation branch 220 for switching, it avoids the problems of waste during venting and low efficiency during the cleaning process of the in-use separation branch 110 pipeline network. The standby separation branch 220 can be equalized by using the venting pressure, reducing the sudden change of the pressure difference in the pipeline network and improving the gas transmission efficiency of the pipeline network at the same time.

[0029] A first stop valve 17 and a first sewage discharge valve 18 are provided on the pipeline connected to the sewage discharge port of the first separator 1. The second separator 2 is provided with a sewage discharge port at the bottom, and a second stop valve 19 and a second sewage discharge valve 20 are provided on the pipeline connected to the sewage discharge port of the second separator 2; a third stop valve 21 and a third sewage discharge valve 22 are provided on the pipeline connected to the sewage discharge port of the third separator 5. The fourth separator 6 is provided with a sewage discharge port at the bottom, and a fourth stop valve 23 and a fourth sewage discharge valve 24 are provided on the pipeline connected to the sewage discharge port of the fourth separator 6. The pipelines connected to the sewage discharge ports of the first separator 1, the second separator 2, the third separator 5, and the fourth separator 6 are aggregated into the main sewage pipe, and a main sewage valve 25 is provided on the main sewage pipe. For the pipeline network connected by multiple in-use separation branches 110, there are many sewage discharge pipelines, and the risk factors during the silt cleaning process are complex. If any pipeline valve is not tightly closed and leaks, it will pose a great hidden danger to the completion of the silt cleaning operation. Therefore, a main sewage valve 25 is added at the main sewage pipe, and the main sewage valve 25 is closed during the silt cleaning process to play a dual protection role, so that the silt cleaning operation can be carried out safely and smoothly.

[0030] The first blowdown valve 18, the second blowdown valve 20 and the third blowdown valve 22 all adopt the valve sleeve type blowdown valve.

[0031] A third ball valve 26 is arranged on the pipeline connecting the first separator 1 to the main pipeline network, and a fourth ball valve 27 is arranged on the pipeline connecting the third separator 5 to the main pipeline network; it is used for switching between the in-use separation branch 110 and the standby separation branch 220 to connect to the main pipeline network.

[0032] In this application, a pressure device and other monitoring instruments are also arranged on the in-use separation branch 110 and the standby separation branch 220, which are not drawn in the figure and belong to the commonly used monitoring devices on the existing in-use separation branch 110.

[0033] During the daily blowdown process, the impurities and moisture separated by the separator enter the blowdown pool through the blowdown pipeline. Control valves are arranged at the bottom of each separator to improve the individual control of each separator and improve control safety.

Claims

1. A natural gas hub station pipeline network sewage system, characterized in that: It includes an in-use separation branch (110) and a standby separation branch (220); The separation branch (110) in use comprises a first separator (1) connected to a main network, the gas outlet of the first separator (1) is connected to a second separator (2), and the sewage outlet of the first separator (1) is connected to a sewage tank (3) through a sewage pipe; the second separator (2) is provided with a vent port, which is connected to a vent area through a vent pipe (4), and the vent pipe (4) is provided with a first gate valve (8) and a first vent valve (9) in sequence; the second separator (2) is provided with an exhaust port, and the exhaust port on the second separator (2) is connected to an exhaust network through a first exhaust pipe (13), and the first exhaust pipe (13) is provided with a first ball valve (14); The standby separation branch (220) comprises a third separator (5) connected to the main network, the gas outlet of the third separator (5) is connected to the fourth separator (6), and the sewage outlet of the third separator (5) is connected to the sewage tank (3) through the sewage pipe; the fourth separator (6) is provided with a vent port, which is connected to the vent pipe (4) of the second separator (2) through the vent pipe (7), the vent pipe (7) is provided with a second gate valve (10) and a second vent valve (11) in sequence, the end of the second vent valve (11) is connected to the end of the first vent valve (9), and the end of the vent pipe (4) is provided with a third vent valve (12); the fourth separator (6) is provided with an exhaust port, the exhaust port on the fourth separator (6) is connected to the exhaust pipe network through the second exhaust pipe (15), and the second exhaust pipe (15) is provided with a second ball valve (16).

2. A natural gas hub station pipeline network sewage discharge system according to claim 1, characterized in that: The third separator (5) and the first separator (1) both adopt cyclone separators.

3. A natural gas hub station pipeline network sewage discharge system according to claim 1, characterized in that: The fourth separator (6) and the second separator (2) are both filter separators.

4. A natural gas hub station pipeline network sewage discharge system according to claim 1, characterized in that: The first vent valve (9) and the second vent valve (11) are both throttle valves.

5. A natural gas hub station pipeline network sewage discharge system according to claim 1, characterized in that: A first stop valve (17) and a first sewage valve (18) are provided on the pipeline connected to the sewage outlet of the first separator (1).

6. A natural gas hub station pipeline network sewage discharge system according to claim 5, characterized in that: A sewage outlet is provided at the bottom of the second separator (2), and a second stop valve (19) and a second sewage valve (20) are provided on the pipeline connected to the sewage outlet of the second separator (2).

7. A natural gas hub station pipeline network sewage discharge system according to claim 6, characterized in that: A third stop valve (21) and a third sewage valve (22) are provided on the pipeline connected to the sewage outlet of the third separator (5).

8. A natural gas hub station pipeline network sewage discharge system according to claim 7, characterized in that: A sewage outlet is provided at the bottom of the fourth separator (6), and a fourth stop valve (23) and a fourth sewage valve (24) are provided on the pipeline connected to the sewage outlet of the fourth separator (6).

9. A natural gas hub station pipeline network sewage discharge system according to claim 8, characterized in that: The pipes connected to the sewage outlets of the first separator (1), the second separator (2), the third separator (5) and the fourth separator (6) are connected to a main sewage pipe, and a main sewage valve (25) is provided on the main sewage pipe.

10. A natural gas hub station pipeline network sewage discharge system according to claim 1, characterized in that: The first sewage discharge valve (18), the second sewage discharge valve (20) and the third sewage discharge valve (22) are all valve sleeve type sewage discharge valves.

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