Pressure relief device and system for crude oil pipeline

Abstract

The present application discloses a pressure relief device and system for crude oil transportation pipeline, belonging to the technical field of oil and gas pipeline pressure relief. The pressure relief device is located on the pipeline in the low-lying part of the large drop pipe section, including a pressure relief pipe, an isolation tank, a pressure relief tank and an elastic airbag; the upper part of the pipeline has a through hole, and the pressure relief pipe is connected to the pipeline through the through hole; the pressure relief pipe, the isolation tank and the pressure relief tank are connected in sequence, and the isolation tank and the pressure relief tank both have an inert liquid that is not miscible with crude oil, the elastic airbag is located in the pressure relief tank, and the elastic airbag is filled with gas, and the opening of the elastic airbag is sealed and connected to the first upper outlet of the pressure relief tank; there is a first control valve between the isolation tank and the pressure relief tank, and there is a second control valve on the upper part of the pressure relief tank, and the device is configured so that when it is used, the first control valve and the second control valve are both in an open state. The device can achieve pressure relief in the low-lying part of the large drop pipeline while occupying relatively less space, ensuring the safe and stable operation of the pipeline.

Description

Technical Field

[0001] The present application relates to the technical field of oil and gas pipeline pressure relief, and in particular to a pressure relief device and system for a crude oil transportation pipeline. Background Art

[0002] In order to facilitate the long-distance transportation of oil and gas, it is usually achieved by laying oil pipelines. For oil pipelines laid on large elevation terrain, the crude oil in the low-lying section has a fast flow rate and strong erosion force, which can easily cause the downstream pipeline in the low-lying section to vibrate. If the crude oil flow rate increases instantly, it will also cause damage to the pipeline, thereby affecting the safe and stable operation of the pipeline.

[0003] In the related technology, a pressure reducing station is usually set up in the low-lying part of the large drop pipe section. A buffer tank is provided in the station. A connecting branch with a valve is provided on the pipeline. The buffer tank is connected to the pipeline through the connecting branch. When the crude oil flow rate increases instantly and pressure relief is required, the valve can be opened to introduce part of the crude oil into the buffer tank to achieve pressure relief.

[0004] However, since the volume of the buffer tank is generally large and is set parallel to the pipeline, the installation of a pressure reducing station will occupy relatively more land. If there is not enough land in the low-lying area, the buffer tank cannot be laid out, and pressure relief cannot be achieved in the low-lying area of ​​the large drop pipe section, affecting the safe and smooth operation of the pipeline. Summary of the invention

[0005] In view of this, the present application provides a pressure relief device and system for a crude oil transportation pipeline, which can achieve pressure relief in low-lying areas of a large drop pipeline while occupying relatively less space, thereby ensuring safe and stable operation of the pipeline.

[0006] Specifically, the following technical solutions are included:

[0007] In a first aspect, a pressure relief device for a crude oil transportation pipeline is provided, the device being located on a pipeline at a low-lying part of a large drop section, comprising: a pressure relief pipe, an isolation tank, a pressure relief tank and an elastic airbag;

[0008] The upper portion of the pipeline is provided with a through hole, and the pressure relief pipe is communicated with the pipeline through the through hole;

[0009] The pressure relief pipe, the isolation tank and the pressure relief tank are connected in sequence, the isolation tank and the pressure relief tank both contain an inert liquid that is immiscible with crude oil, the elastic airbag is located in the pressure relief tank, and the elastic airbag is filled with gas, and the opening of the elastic airbag is sealed and connected to the first upper outlet of the pressure relief tank;

[0010] A first control valve is provided between the isolation tank and the pressure relief tank, and a second control valve is provided on the upper portion of the pressure relief tank. When the device is configured to be in use, both the first control valve and the second control valve are in an open state.

[0011] In a possible design, the axial direction of the pressure relief pipe is perpendicular to the ground.

[0012] In one possible design, the volume of the isolation tank is 45m 3 ~60m 3 , and a filling valve is provided at the lower part of the isolation tank.

[0013] In one possible design, the density of the inert liquid is greater than the density of the crude oil in the pipeline.

[0014] In a possible design, the second lower outlet of the isolation tank is connected to the first lower outlet of the pressure relief tank through a second connecting piece, and the first control valve is located on the second connecting piece;

[0015] The second connecting member is connected to the pipeline via a fixing member.

[0016] In one possible design, the volume of the pressure relief tank is 25m 3 ~40m 3 .

[0017] In a possible design, the elastic airbag is made of glass fiber.

[0018] In a possible design, the first upper outlet of the pressure relief tank has a first connecting piece, and the second control valve is located on the first connecting piece;

[0019] The first connecting member is also provided with an inflation valve.

[0020] In one possible design, both the first control valve and the second control valve are remote control valves;

[0021] The first control valve and the second control valve are connected to a control system signal.

[0022] In a second aspect, a pressure relief system for a crude oil pipeline is provided, the system comprising a pipeline and a pressure relief device for a crude oil pipeline according to any one of the first aspects;

[0023] The upper portion of the pipeline is provided with a through hole, and the pressure relief device is communicated with the pipeline through the through hole.

[0024] The beneficial effects of the technical solution provided by the embodiments of the present application include at least:

[0025] When the crude oil flow in the pipeline located in the low-lying part of the large drop pipe section increases instantly and needs to be relieved, the first control valve and the second control valve are opened. Due to the opening of the first control valve and the second control valve, the pressure in the device is atmospheric pressure. Since the pressure in the pipeline is greater than the atmospheric pressure, the crude oil in the pipeline will enter the pressure relief pipe through the through hole under the action of the pressure difference, and the crude oil will impact the pressure relief pipe to achieve the pressure relief of the crude oil; then, when the crude oil flows into the isolation tank through the pressure relief pipe, the pressure relief of the crude oil can be continued by impacting the isolation tank; due to the impact of the crude oil, the inert liquid in the isolation tank that is not miscible with the crude oil will continuously flow into the pressure relief tank to squeeze the elastic airbag located in the pressure relief tank, so that the gas in the elastic airbag continuously flows out through the second control valve, converts the hydraulic pressure into air pressure and then releases it, further achieving the pressure relief of the crude oil;

[0026] Since the device is located on the pipeline at the low point of the large drop section instead of being set parallel to the pipeline, the land required for setting up the pressure reducing station is greatly reduced;

[0027] By filling the isolation tank and the pressure relief tank with an inert liquid that is immiscible with crude oil, the crude oil is prevented from entering the pressure relief tank, thereby effectively preventing the corrosion of the pressure relief tank by crude oil. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 A schematic structural diagram of a pressure relief device for a crude oil pipeline provided in an embodiment of the present application;

[0030] Figure 2 A schematic diagram of the connection between a first control valve 7 and a second control valve 8 and a control system 14 in a pressure relief device for a crude oil pipeline provided in an embodiment of the present application.

[0031] The reference numerals in the figures represent respectively:

[0032] 1- Pipeline,

[0033] 101 - through hole,

[0034] 2-Pressure relief pipe,

[0035] 3- Isolation tank,

[0036] 31-Second lower exit,

[0037] 32-Second upper exit,

[0038] 4- Pressure relief tank,

[0039] 41-First upper exit,

[0040] 42-First exit,

[0041] 5- Elastic airbag,

[0042] 51-Opening,

[0043] 6- Inert liquid,

[0044] 7- First control valve,

[0045] 8- Second control valve,

[0046] 9-Filling valve,

[0047] 10- first connecting member,

[0048] 1001- Second connecting elbow,

[0049] 1002- Third connecting elbow,

[0050] 11-Fixer,

[0051] 1101-first sub-component,

[0052] 1102-Second sub-component,

[0053] 12- Second connecting piece,

[0054] 13-Inflation valve,

[0055] 14- Control system,

[0056] 15- The third connecting piece.

[0057] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0058] Before further describing the embodiments of the present application in detail, the directional nouns involved in the embodiments of the present application, such as "upper part", "lower part", "upper exit", and "lower exit", are all referred to as "upper part", "lower exit ... Figure 1 The orientation shown in is a reference and is only used to clearly describe the structure of the pressure relief device and system for the crude oil pipeline in the embodiment of the present application, and does not limit the protection scope of the present application.

[0059] Unless otherwise defined, all technical terms used in the embodiments of the present application have the same meanings as commonly understood by those skilled in the art.

[0060] In order to make the technical solutions and advantages of the present application more clear, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0061] In order to facilitate the long-distance transportation of oil and gas, it is currently a common practice to achieve this by laying long-distance oil pipelines. In the process of laying long distances, it is inevitable to encounter large-drop terrain. The large drop here refers to the area from high altitude to low altitude. It is understandable that when oil and gas pass through large-drop terrain, the gravitational potential energy will be converted into kinetic energy, so the crude oil flow rate in the low-lying pipe section with a large drop is fast and the erosion force is large, which can cause the downstream pipeline in the low-lying pipe section to vibrate. If the crude oil flow rate increases instantly, it will also cause damage to the pipeline, affecting the safe and stable operation of the pipeline.

[0062] In view of this, the relevant technology usually sets up a pressure relief station in the low-lying part of the large drop pipe section. The station is equipped with a buffer tank, which is connected to the pipeline through a branch pipe connected to the pipeline. When the crude oil flow rate increases instantly to the point where pressure relief is required, pressure relief can be achieved by introducing part of the crude oil into the buffer tank. However, since the volume of the buffer tank is generally large and is set parallel to the pipeline, it occupies a large area. If there is not enough land in the low-lying area, the tank cannot be laid and pressure relief cannot be performed, which affects the safe and stable operation of the pipeline.

[0063] In order to solve the problem that the buffer tank provided in the related art occupies a large area and cannot achieve pressure relief in the low-lying parts of the pipeline with a large drop, the present application provides a pressure relief device and system for a crude oil transportation pipeline.

[0064] like Figure 1 , which is a schematic diagram of a pressure relief device for a crude oil pipeline provided in an embodiment of the present application. The device is located on the pipeline 1 at a low-lying part of a large drop section, rather than being arranged parallel to the pipeline 1, which can effectively reduce the land occupation.

[0065] See also Figure 1 The device includes: a pressure relief pipe 2, an isolation tank 3, a pressure relief tank 4 and an elastic airbag 5.

[0066] The upper part of the pipeline 1 has a through hole 101, and the pressure relief pipe 2 is connected to the pipeline 1 through the through hole 101. The pipeline 1 is a main pipe for crude oil transportation, and the pressure relief pipe 2 is equivalent to a branch pipe of the main pipe. The crude oil in the pipeline 1 can enter the pressure relief pipe 2 through the through hole 101, and then enter the pressure relief device for the crude oil transportation pipeline.

[0067] It is understandable that the pressure relief pipe 2 needs to be sealed and fixedly connected to the pipeline 1 at the through hole 101 to prevent leakage of crude oil from entering the pressure relief pipe 2 from the pipeline 1. The connection between the lower end of the pressure relief pipe 2 and the pipeline 1 can be welded.

[0068] The pressure relief pipe 2 , the isolation tank 3 and the pressure relief tank 4 are connected in sequence, that is, the pressure relief pipe 2 is connected to the isolation tank 3 , and the isolation tank 3 is connected to the pressure relief tank 4 .

[0069] Both the isolation tank 3 and the pressure relief tank 4 contain an inert liquid 6 that is immiscible with crude oil. The inert liquid 6 can flow between the isolation tank 3 and the pressure relief tank 4, so that the crude oil cannot leave the isolation tank 3 and enter the pressure relief tank 4, which can effectively prevent the crude oil from corroding the pressure relief tank 4.

[0070] The elastic airbag 5 is located in the pressure relief tank 4 and is filled with gas. The opening 51 of the elastic airbag 5 is sealedly connected to the first upper outlet 41 of the pressure relief tank 4, so that the first upper outlet 41 of the pressure relief tank 4 can only discharge the gas in the elastic airbag 5 but cannot discharge the inert liquid 6 in the pressure relief tank 4 to prevent the inert liquid 6 from leaking out.

[0071] There is a first control valve 7 between the isolation tank 3 and the pressure relief tank 4, and a second control valve 8 is provided on the upper part of the pressure relief tank 4. When the device is configured to be used, the first control valve 7 and the second control valve 8 are both in an open state. Since the first control valve 7 and the second control valve 8 are both open, the device is connected to the atmospheric pressure, that is, the pressure of the device is the atmospheric pressure. Since the pressure in the pipeline 1 is greater than the atmospheric pressure, the liquid in the pipeline 1 can enter the device under the action of the pressure difference.

[0072] The working principle of the pressure relief device for crude oil pipeline provided in the embodiment of the present application is:

[0073] When the crude oil flow in the pipeline 1 located in the low-lying part of the large drop pipe section increases instantly and needs to be depressurized, the first control valve 7 and the second control valve 8 are opened. Due to the opening of the first control valve 7 and the second control valve 8, the pressure in the device is atmospheric pressure. Since the pressure in the pipeline 1 is greater than the atmospheric pressure, the crude oil in the pipeline 1 will enter the pressure relief pipe 2 through the through hole 101 under the action of the pressure difference, and the crude oil will impact the pressure relief pipe 2 to achieve the pressure relief of the crude oil;

[0074] Then, when the crude oil flows into the isolation tank 3 through the pressure relief pipe 2, the pressure relief of the crude oil can be further achieved by impacting the isolation tank 3;

[0075] Due to the impact of crude oil, the inert liquid 6 in the isolation tank 3 that is not miscible with the crude oil will continuously flow into the pressure relief tank 4 to squeeze the elastic airbag 5 located in the pressure relief tank 4, so that the gas in the elastic airbag 5 continuously flows out through the second control valve 8, converting the hydraulic pressure into air pressure and then releasing it, thereby further achieving the pressure relief of the crude oil.

[0076] Therefore, by setting the device on the pipeline 1, replacing the buffer tank body set parallel to the pipeline 1 in the related technology, the land required for setting up the pressure reducing station is greatly reduced. When the crude oil flow in the pipeline 1 located in the low-lying part of the large drop pipe section increases instantly, the first control valve 7 and the second control valve 8 can be opened, and the pressure relief pipe 2, the isolation tank 3 and the pressure relief tank 4 can be used to perform layer-by-layer pressure relief. The pressure relief device for the crude oil transportation pipeline in the embodiment of the present application can achieve pressure relief in the low-lying part of the large drop pipeline while occupying relatively less space, thereby ensuring the safe and smooth operation of the pipeline 1.

[0077] In one possible design, see Figure 1 The axial direction of the pressure relief pipe 2 is perpendicular to the ground, that is, the pressure relief pipe 2 is arranged perpendicular to the ground, so that when the crude oil enters the pressure relief pipe 2, it can not only achieve pressure relief by impacting the pressure relief pipe 2, but also the crude oil can convert its own kinetic energy into gravitational potential energy to further achieve pressure relief.

[0078] Optionally, the length of the pressure relief pipe 2 can be set according to the numerical value of the step difference in the large drop area. When the value of the drop is large, the length of the pressure relief pipe 2 is set longer; when the value of the drop is small, the length of the pressure relief pipe 2 is set shorter.

[0079] Optionally, when the height difference is large and the pressure relief pipe 2 is long, in order to ensure the stability of the pressure relief pipe 2 , a fixed bracket (not shown in the figure) may be provided around the pressure relief pipe 2 to support and fix the pressure relief pipe 2 .

[0080] Optionally, the pressure relief pipe 2 is made of stainless steel to prevent corrosion by crude oil.

[0081] For example, the pressure relief pipe 2 may be made of Q345 steel, which is easy to obtain and manufacture.

[0082] Optionally, the applicable pressure of the pressure relief pipe 2 may be 0.5 MPa to 10 MPa, and the applicable temperature may be -5°C to 65°C.

[0083] It is understandable that crude oil can only flow at a certain temperature, which is generally between 20°C and 60°C. If the temperature is too low, the viscosity of the crude oil increases, resulting in poor fluidity and difficulty in transportation.

[0084] In one possible design, see Figure 1In order to realize the connection between the pressure relief pipe 2 and the isolation tank 3, a third connecting piece 15 is provided between the upper end of the pressure relief pipe 2 and the second upper outlet 32 ​​of the isolation tank 3. At the same time, by providing the third connecting piece 15, the isolation tank 3 can be located on one side of the pressure relief pipe 2.

[0085] Optionally, the third connecting member 15 may be a first connecting elbow.

[0086] It is understandable that, for the connecting elbow structure, its essence is a curved pipe body, which is hollow inside and can provide a circulation channel for gas or liquid. For the first connecting elbow, the first connecting elbow can provide a circulation channel for crude oil.

[0087] Optionally, the connection between the third connecting member 15 and the pressure relief pipe 2, and the connection between the third connecting member 15 and the isolation tank 3 can both be threaded connections, which are convenient for installation and disassembly.

[0088] In one possible design, the volume of the isolation tank 3 is 45m 3 ~60m 3 , which is convenient for fixed installation on pipeline 1. When the crude oil flow in pipeline 1 located in the low-lying part of the large drop pipeline increases instantly, partial pressure relief is required. By setting the volume of isolation tank 3 to 45m 3 ~60m 3 , it is possible to divert the crude oil in pipeline 1 within 2 to 5 minutes, so that the on-site operators can adjust the crude oil flow upstream of pipeline 1 during this period of time to avoid continuous impact on pipeline 1 located in the low-lying part of the large drop pipeline.

[0089] Optionally, for ease of operation, the isolation tank 3 is provided with a liquid level display, through which the liquid level of the liquid in the isolation tank 3 can be easily obtained.

[0090] Optionally, the liquid level display is connected to the control system 14 signal, and the staff can obtain the liquid level value in the isolation tank 3 in the monitoring station. The liquid level value may include the liquid level value after the inert liquid 6 is injected, the liquid level value after the pressure is released, and the like.

[0091] In one possible design, see Figure 1 The lower part of the isolation tank 3 is provided with a filling valve 9, through which an inert liquid 6 that is immiscible with crude oil can be filled into the isolation tank 3.

[0092] In a possible design, the inert liquid 6 is not only immiscible with the crude oil, but also has a density greater than the density of the crude oil in the pipeline 1, so that when the crude oil enters the isolation tank 3 filled with the inert liquid 6, the inert liquid 6 will not splash around.

[0093] Optionally, the inert liquid 6 may be glycerol.

[0094] Optionally, the inert liquid 6 may be liquid paraffin. When the inert liquid 6 is liquid paraffin, it is necessary to ensure that the environment in which the liquid paraffin is located is above 20° C. to ensure that the liquid paraffin is liquid.

[0095] In one possible design, see Figure 1 In order to connect the isolation tank 3 with the pressure relief tank 4 , the second lower outlet 31 of the isolation tank 3 is connected with the first lower outlet 42 of the pressure relief tank 4 through the first connecting piece 10 , and the first control valve 7 is located on the first connecting piece 10 .

[0096] Optionally, the first connecting member 10 includes a second connecting elbow 1001 and a third connecting elbow 1002 .

[0097] Among them, the second lower outlet 31 of the isolation tank 3 is connected to one end of the second connecting elbow 1001, the other end of the second connecting elbow 1001 is connected to one end of the first control valve 7, the other end of the first control valve 7 is connected to one end of the third connecting elbow 1002, and the other end of the third connecting elbow 1002 is connected to the first lower outlet 42 of the pressure relief tank 4, that is, the first control valve 7 is located between the second connecting elbow 1001 and the third connecting elbow 1002.

[0098] As for the second connecting elbow 1001 and the third connecting elbow 1002 , both can provide a circulation channel for the inert liquid 6 .

[0099] Optionally, threaded connections can be made between the second lower outlet 31 of the isolation tank 3 and the second connecting elbow 1001, between the other end of the second connecting elbow 1001 and the first control valve 7, between the other end of the first control valve 7 and the third connecting elbow 1002, and between the other end of the third connecting elbow 1002 and the first lower outlet 42 of the pressure relief tank 4 to facilitate installation and disassembly.

[0100] In a possible design, the first connecting member 10 is connected to the pipeline 1 through a fixing member 11 to ensure that the isolation tank 3 and the pressure relief tank 4 can be stably fixed on the pipeline 1 .

[0101] Optional, see Figure 1 The fixing member 11 includes a first sub-member 1101 and a second sub-member 1102. The second connecting elbow 1001 is connected to the pipeline 1 through the first sub-member 1101, and the third connecting elbow 1002 is connected to the pipeline 1 through the second sub-member 1102 to ensure the stability of the connection.

[0102] In one possible design, the volume of the pressure relief tank 4 is 25m 3 ~40m 3 , which is smaller than the volume of the isolation tank 3 and is also convenient for installation on the pipeline 1.

[0103] In a possible design, the elastic airbag 5 is made of glass fiber, which has good corrosion resistance and heat resistance, and can effectively separate the gas in the elastic airbag 5 from the inert liquid 6 .

[0104] In one possible design, see Figure 1 The first upper outlet 41 of the pressure relief tank 4 has a second connecting piece 12, and the second control valve 8 is located on the second connecting piece 12. By providing the second connecting piece 12, the second control valve 8 is conveniently provided.

[0105] Optionally, the second connecting member 12 may be a fourth connecting elbow.

[0106] Here, the fourth connecting elbow can provide a circulation channel for the gas.

[0107] In one possible design, see Figure 1 The second connecting member 12 also has an inflation valve 13 to facilitate inflation into the elastic airbag 5.

[0108] Optionally, the gas in the elastic airbag 5 may be air or nitrogen.

[0109] Among them, the gas is preferably air, which is easy to obtain and has low cost.

[0110] In a possible design, the first control valve 7 and the second control valve 8 are both remote control valves. Since the crude oil flow in the pipeline located in the low-lying part of the large drop pipe section may increase instantaneously due to various complex reasons, for example, the upstream flow increases instantaneously, and the increase is discovered by a pressure measuring instrument installed on the pipe section located in the low-lying part, the measuring instrument sends the value in the form of an electrical signal to the control system 14 located in the monitoring station, so that the staff can find that the crude oil flow in the pipeline located in the low-lying part of the large drop pipe section has increased instantaneously and needs to release the pressure. When it is found that the crude oil flow in the pipeline located in the low-lying part of the large drop pipe section has increased instantaneously, the danger has already occurred, and the staff cannot rush to the scene to open the first control valve 7 and the second control valve 8 in a short time (for example, within 5 minutes). Therefore, in order to facilitate the control of the first control valve 7 and the second control valve 8, the first control valve 7 and the second control valve 8 can be set as remote control valves, that is, see Figure 2 , the first control valve 7 and the second control valve 8 can be connected to the control system 14 by signal. When it is found that the crude oil flow in the pipeline at the low-lying part of the large drop pipe section has increased instantly, the staff can send an opening signal to the first control valve 7 and the second control valve 8 through the control system 14, so that the first control valve 7 and the second control valve 8 are opened, and the pressure relief of the pressure relief device for the crude oil transportation pipeline provided by the embodiment of the present application is realized.

[0111] The first control valve 7 and the second control valve 8 are both provided with a signal receiving component and an execution component. The signal receiving component is used to receive the control signal sent by the control system 14, and the execution component is used to control the opening and closing of the valve.

[0112] It is understandable that when the crude oil flow in the pipeline at the low-lying part of the large drop pipe section no longer increases, the control system 14 can send a closing signal to the first control valve 7 and the second control valve 8 .

[0113] Due to the pressure relief, part of the crude oil is stored in the isolation tank 3. In order not to affect the next use of the pressure relief device for the crude oil pipeline provided by the embodiment of the present application, when the crude oil flow in the pipeline located in the low-lying part of the large drop pipe section is within the normal value range, the operator needs to open the first control valve 7 on site, and inflate the elastic airbag 5 from the inflation valve 13. Under the push of air pressure, the crude oil enters the pressure relief pipe 2 from the isolation tank 3, and then returns to the pipeline 1 from the pressure relief pipe 2. During this operation, the staff can judge whether the operation can be ended by observing the liquid level display located on the isolation tank 3, that is, when the liquid level returns to the liquid level value after the inert liquid 6 is injected, it means that the operation is ended.

[0114] In one possible design, before the pipeline 1 is laid, the pressure relief device for a crude oil transportation pipeline provided in an embodiment of the present application can be set on the pipeline 1, that is, before the pipeline 1 is laid, the various components in the device have been connected; or before the pipeline 1 is laid, only the pressure relief pipe 2 is connected, and before the pipeline 1 needs to be operated, other components of the pressure relief device for a crude oil transportation pipeline provided in an embodiment of the present application except the pressure relief pipe 2 are connected, which are not specifically limited here.

[0115] In a possible design, when the pipeline 1 is located above the ground, the pressure relief device can be installed and fixed on the pipeline 1.

[0116] In a possible design, when the pipeline 1 is located below the ground, part of the pressure relief pipe 2 is also located below the ground, while other structures of the device are located above the ground and fixed on the ground, while ensuring that they are located above the pipeline 1 .

[0117] In one possible example, before the pipeline 1 is laid, the pressure relief device for the crude oil transportation pipeline provided in the embodiment of the present application is set on the pipeline 1. When the control system 14 detects that the crude oil flow in the pipeline 1 located in the low-lying part of the large drop pipe section increases instantly and needs pressure relief, the staff operates the control system 14 to open the first control valve 7 and the second control valve 8 to achieve pressure relief.

[0118] The embodiment of the present application also provides a pressure relief system for a crude oil transportation pipeline, comprising a pipeline 1 and the above-mentioned pressure relief device for a crude oil transportation pipeline.

[0119] See also Figure 1 The upper portion of the pipeline 1 has a through hole 101 , and the pressure relief device is connected to the pipeline 1 through the through hole 101 .

[0120] It can be understood that the specific structure and usage of the pressure relief device have been described in detail in the above embodiments and will not be repeated here.

[0121] In the present application, the terms "first", "second" and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. The term "plurality" refers to two or more than two, unless otherwise clearly defined.

[0122] The above is only to facilitate those skilled in the art to understand the technical solution of this application and is not intended to limit this application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included in the protection scope of this application.

Claims

1. A pressure relief device for a crude oil pipeline, characterized in that: The device is located on a pipeline (1) at a low-lying part of a large drop pipe section, and comprises: a pressure relief pipe (2), an isolation tank (3), a pressure relief tank (4) and an elastic air bag (5); The upper portion of the pipeline (1) has a through hole (101), the pressure relief pipe (2) is connected to the pipeline (1) through the through hole (101), and the axial direction of the pressure relief pipe (2) is perpendicular to the ground; The pressure relief pipe (2), the isolation tank (3) and the pressure relief tank (4) are connected in sequence; the isolation tank (3) and the pressure relief tank (4) both contain an inert liquid (6) that is immiscible with crude oil; the density of the inert liquid (6) is greater than the density of the crude oil in the pipeline (1); the elastic airbag (5) is located in the pressure relief tank (4), and the elastic airbag (5) is filled with gas; the opening (51) of the elastic airbag (5) is sealedly connected to the first upper outlet (41) of the pressure relief tank (4); A first control valve (7) is provided between the isolation tank (3) and the pressure relief tank (4), and a second control valve (8) is provided on the upper part of the pressure relief tank (4). When the device is configured to be in use, both the first control valve (7) and the second control valve (8) are in an open state.

2. The pressure relief device for crude oil transportation pipeline according to claim 1, characterized in that: The volume of the isolation tank (3) is 45 m 3 ~60m 3 , and a filling valve (9) is provided at the lower part of the isolation tank (3).

3. The pressure relief device for a crude oil pipeline according to claim 1, characterized in that: The second lower outlet (31) of the isolation tank (3) is connected to the first lower outlet (42) of the pressure relief tank (4) via a first connecting piece (10), and the first control valve (7) is located on the first connecting piece (10); The first connecting member (10) is connected to the pipeline (1) via a fixing member (11).

4. The pressure relief device for a crude oil pipeline according to claim 1, characterized in that: The volume of the pressure relief tank (4) is 25 m 3 ~40m 3 .

5. The pressure relief device for crude oil transportation pipeline according to claim 1, characterized in that: The elastic airbag (5) is made of glass fiber.

6. The pressure relief device for a crude oil pipeline according to claim 1, characterized in that: The first upper outlet (41) of the pressure relief tank (4) has a second connecting piece (12), and the second control valve (8) is located on the second connecting piece (12); The second connecting member (12) is also provided with an inflation valve (13).

7. The pressure relief device for a crude oil pipeline according to claim 1, characterized in that: The first control valve (7) and the second control valve (8) are both remote control valves; The first control valve (7) and the second control valve (8) are connected to a control system (14) via signals.

8. A pressure relief system for a crude oil pipeline, characterized in that: The system comprises a pipeline (1) and a pressure relief device for a crude oil transportation pipeline according to any one of claims 1 to 7; The upper portion of the pipeline (1) is provided with a through hole (101), and the pressure relief device is connected to the pipeline (1) through the through hole (101).

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