A method and apparatus for removing a wax or hydrate plug from an oil and gas pipeline

Abstract

The application relates to a kind of oil and gas pipeline wax or hydrate blockage unblocking devices, including main body part, flow guide head and jet pipe, flow guide head is arranged above main body part, and flow guide head is conical structure with opening towards main body part, jet pipe is arranged on main body part, and the top end of jet pipe is connected with flow guide head, the bottom end of jet pipe is used to connect reagent pump, there is buffer gap between flow guide head and main body part, and a plurality of jet holes are arranged on the pipe body of buffer gap where jet pipe is located.The reverse thrust of liquid jet acting on flow guide head can push the unblocking device to run along the pipeline to the blockage position, so that the chemical reagent can be brought to the blockage position, and the wax or hydrate blockage in oil and gas pipeline can be effectively removed.

Description

Technical Field

[0001] This invention relates to the field of petrochemical technology, specifically to a device and method for unblocking wax or hydrate blockages in oil and gas pipelines. Background Technology

[0002] Most of my country's crude oil has a high wax content, especially in offshore oil and gas fields. During the actual operation of oil pipelines, due to the low temperature of the seabed environment, the crude oil's wax-dissolving capacity decreases with decreasing temperature and pressure. Paraffin wax begins to crystallize and precipitate, adhering to the inner wall of the pipeline. The continuous precipitation and deposition of paraffin wax reduces the pipeline's throughput diameter, eventually leading to blockage. The problem of wax deposition in oil pipelines has long plagued normal oilfield production. Currently, common methods for unblocking pipelines with wax include physical and chemical methods. Physical methods utilize physical forces to break up the blockage, including high-pressure water jetting, mechanical methods, acoustic methods, electric field methods, and magnetic field methods. Chemical methods often involve injecting specialized chemical reagents into the pipeline to flush it and dissolve the blockage. However, for wax blockages in subsea pipelines, existing physical methods are difficult to implement and extremely expensive, and there is currently no better way to inject unblocking agents directly into the blockage for effective unblocking.

[0003] Furthermore, natural gas hydrates are cage-like compounds formed by the reaction of natural gas with water under low-temperature and high-pressure conditions. With the development of deep-water oil and gas fields, the high-pressure and low-temperature environment in deep water makes oil and gas gathering and transportation systems highly susceptible to hydrate formation, often accompanied by the risk of blockage. For hydrate blockages in pipelines, local heating of the pipeline or direct injection of hydrate inhibitors is commonly used for unblocking, or a double-sided depressurization method can also be employed. However, due to the significant differences between offshore operations and production processes and those onshore operations, simply copying the hydrate unblocking methods used in onshore oil and gas fields for hydrate blockages in subsea production facilities of offshore oil and gas fields is not effective in relieving hydrate blockages in subsea pipelines. Currently, double-sided depressurization is commonly used for hydrate unblocking, but due to pipeline undulations and other factors, effective double-sided depressurization at the hydrate blockage site is sometimes difficult to achieve. On the other hand, due to pipeline blockage, it is impossible to deliver the chemical reagents to the hydrate blockage site with the flowing medium, making hydrate unblocking difficult. Summary of the Invention

[0004] The purpose of this invention is to provide a device and method for unblocking wax or hydrate blockages in oil and gas pipelines, so as to solve the problem of difficulty in unblocking wax or hydrate blockages in oil and gas pipelines in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] This invention provides a device for unblocking oil and gas pipelines clogged with wax or hydrate, comprising a main body, a guide head, and an injection pipe. The guide head is disposed above the main body and has a tapered structure with its opening facing the main body. The injection pipe passes through the main body and its top end is connected to the guide head. The bottom end of the injection pipe is used to connect to a chemical pump. There is a buffer gap between the guide head and the main body, and the injection pipe has several injection holes on its body located in the buffer gap.

[0007] Furthermore, the flow guide head includes a first side plate and a second side plate, which are integrally formed and set at an angle. The top ends of the first side plate and the second side plate connected together constitute the tip of the flow guide head, and the bottom ends of the first side plate and the second side plate away from each other constitute the opening end of the flow guide head. The injection pipe is arranged along the central axis of the flow guide head.

[0008] Furthermore, the included angle between the first side plate and the second side plate is less than or equal to 90°.

[0009] Furthermore, the main body has a columnar structure, and the diameter of the open end of the guide head is the same as the diameter of the main body.

[0010] Furthermore, the bottom end of the main body has an arc-shaped round bottom structure.

[0011] Furthermore, a first fixed baffle is horizontally provided on the inner side of the flow guide head. One end of the first fixed baffle is fixed to the inner side plate of the first side plate, and the other end of the first fixed baffle is fixed to the inner side plate of the second side plate. A through hole for the spray pipe to pass through is provided in the middle of the first fixed baffle, and a limiting plate is fixed to the end of the spray pipe located above the first fixed baffle.

[0012] Furthermore, a second fixed baffle is horizontally provided on the inner side of the flow guide head above the first fixed baffle. One end of the second fixed baffle is fixed to the inner side plate of the first side plate, and the other end of the second fixed baffle is fixed to the inner side plate of the second side plate. There is a gap between the second fixed baffle and the first fixed baffle for the flow guide head to float up and down.

[0013] Based on the above-mentioned device for unblocking wax or hydrate blockages in oil and gas pipelines, the present invention also provides a method for unblocking wax or hydrate blockages in oil and gas pipelines, comprising:

[0014] Based on the pipe diameter and local curvature radius of the blocked oil and gas pipeline, select a deblocking device with appropriate diameter and length, and select a chemical delivery hose of appropriate length and diameter and a matching chemical pump based on the location of the blockage point in the oil and gas pipeline and the required flow rate of the injected agent.

[0015] Place the unblocking device into the blocked oil and gas pipeline, start the chemical pump to make the unblocking device run along the pipeline under the action of chemical reaction force, and adjust the flow rate of the chemical pump according to the running resistance of the unblocking device to adjust the movement speed of the unblocking device.

[0016] After the unblocking device reaches the blockage point, the agent is continuously injected and left to stand for a set time. Then, the unblocking device is moved continuously based on the decomposition of the blockage at the blockage point until the blockage in the oil and gas pipeline is completely cleared.

[0017] The present invention, by adopting the above technical solution, has the following beneficial effects:

[0018] The device consists of a main body, a guide head, and an injection pipe. The guide head has a tapered structure with its opening facing the main body. The injection pipe connects the guide head and a chemical pump. By activating the pump, chemical agents are injected into the injection pipe. These agents are then ejected from injection holes located in the buffer gap between the guide head and the main body. The liquid jet's reaction force on the guide head propels the device along the pipeline to the blockage location, facilitating the delivery of the chemical agents to the blockage point. This effectively removes wax or hydrate blockages in oil and gas pipelines. The device is simple to operate and significantly reduces costs and time compared to conventional methods, demonstrating promising application prospects. Attached Figure Description

[0019] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. In the drawings:

[0020] Figure 1 This is a schematic diagram of the overall structure of a device for unblocking wax or hydrate blockages in oil and gas pipelines provided in an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the unblocking state of an unblocking device for wax or hydrate blockage in oil and gas pipelines provided in an embodiment of the present invention.

[0022] The markings in the attached diagram are as follows:

[0023] 1. Main body; 2. Guide head; 21. First side plate; 22. Second side plate; 23. First fixed baffle; 24. Second fixed baffle; 3. Injection pipe; 4. Agent pump; 5. Injection hole; 6. Oil and gas pipeline; 7. Agent delivery hose. Detailed Implementation

[0024] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0025] Traditional methods of unblocking oil and gas pipelines due to wax or hydrate buildup are difficult. This invention provides a device for unblocking wax or hydrate blockages in oil and gas pipelines, comprising a main body, a guide head, and an injection pipe. The guide head is positioned above the main body and has a tapered structure with its opening facing the main body. The injection pipe passes through the main body, with its top end connected to the guide head and its bottom end connected to a chemical pump. A buffer gap exists between the guide head and the main body, and the injection pipe at the buffer gap has several injection holes. This invention utilizes the counter-propulsion force of the liquid injection acting on the guide head to propel the unblocking device along the pipeline to the blockage location, thereby facilitating the delivery of chemical agents to the blockage point and effectively relieving wax or hydrate blockages in oil and gas pipelines.

[0026] The present invention will be described in detail below through embodiments.

[0027] Example

[0028] like Figure 1 and Figure 2As shown, this invention provides a device for unblocking wax or hydrate blockages in oil and gas pipelines, comprising a main body 1, a guide head 2, and an injection pipe 3. The guide head 2 is positioned above the main body 1 and has a tapered structure with its opening facing the main body 1. The injection pipe 3 passes through the main body 1, with its top end connected to the guide head 2 and its bottom end used to connect to a chemical pump 4. A buffer gap exists between the guide head 2 and the main body 1, and the injection pipe 3 has several injection holes 5 on its body located in the buffer gap. The size and distribution of the injection holes 5 are uniformly distributed along the circumference of the injection pipe 3. With this structure, simply start the chemical pump 4 to inject chemical agents into the injection pipe 3, and the chemical agents will be sprayed out from the injection hole 5 on the pipe body located in the buffer gap between the guide head 2 and the main body 1. The liquid jet will act on the guide head 2 to push the unblocking device to the blockage position along the oil and gas pipeline 6, thus making it easier to carry the chemical agents to the blockage point and effectively remove the wax or hydrate blockage in the oil and gas pipeline 6.

[0029] Furthermore, the guide head 2 includes a first side plate 21 and a second side plate 22, which are integrally formed and arranged at an angle. The top ends of the first side plate 21 and the second side plate 22 connected together form the tip of the guide head 2, and the bottom ends of the first side plate 21 and the second side plate 22 far apart form the opening end of the guide head 2. The injection pipe 3 is arranged along the central axis of the guide head 2. Preferably, the angle between the first side plate 21 and the second side plate 22 is less than or equal to 90°. With this structure, when the unblocking device runs along the oil and gas pipeline 6, the conical structure of the guide head 2 can reduce the running resistance of the unblocking device and facilitate the reaction force of the liquid injection acting on the guide head 2 to push the unblocking device to run along the oil and gas pipeline 6. At the same time, the angle between the first side plate 21 and the second side plate 22 can be appropriately reduced according to the running resistance of the unblocking device to increase the reaction force generated by the injection.

[0030] Preferably, the main body 1 has a columnar structure, and the diameter of the open end of the guide head 2 is the same as the diameter of the main body 1, so as to avoid the device getting stuck when the unblocking device runs along the pipeline.

[0031] Furthermore, the bottom of the main body 1 has an arc-shaped round bottom structure, so as to maintain the stability of the unblocking device and prevent it from getting stuck when it exits the oil and gas pipeline 6.

[0032] Furthermore, a first fixed baffle 23 is horizontally provided on the inner side of the guide head 2. One end of the first fixed baffle 23 is fixed to the inner side plate of the first side plate 21, and the other end of the first fixed baffle 23 is fixed to the inner side plate of the second side plate 22. A through hole for the injection pipe 3 to pass through is provided in the middle of the first fixed baffle 23, and a limiting plate is fixed to the end of the injection pipe 3 located above the first fixed baffle 23. Through this structure, the guide head 2 is movably connected to the injection pipe 3, thereby allowing the guide head 2 to rotate due to the counter-thrust force generated by the injection of the agent, and preventing the agent delivery hose 7 from twisting during the advancement of the unblocking device.

[0033] Furthermore, a second fixed baffle 24 is horizontally arranged above the first fixed baffle 23 on the inner side of the guide head 2. One end of the second fixed baffle 24 is fixed to the inner side surface of the first side plate 21, and the other end of the second fixed baffle 24 is fixed to the inner side surface of the second side plate 22. There is a gap between the second fixed baffle 24 and the first fixed baffle 23 for the guide head 2 to float up and down. With this structure, the second fixed baffle 24 can slightly buffer the resistance encountered by the unblocking device during its forward movement, ensuring that the unblocking device can move forward stably.

[0034] Based on the above-mentioned device for unblocking wax or hydrate blockages in oil and gas pipelines, the present invention also provides a method for unblocking wax or hydrate blockages in oil and gas pipelines, comprising:

[0035] Based on the diameter and local curvature radius of the blocked oil and gas pipeline 6, select a suitable unblocking device with appropriate diameter and length, and select a suitable length and diameter of chemical delivery hose 7 and matching chemical pump 4 based on the location of the blockage point in the oil and gas pipeline 6 and the required flow rate of the injected agent.

[0036] Place the unblocking device into the blocked oil and gas pipeline 6, start the chemical pump 4 to make the unblocking device run along the pipeline under the action of chemical reaction force, and adjust the flow rate of the chemical pump 4 according to the running resistance of the unblocking device to adjust the movement speed of the unblocking device.

[0037] After the unblocking device reaches the blockage point, the agent is continuously injected and left to stand for a set time. Then, based on the decomposition of the blockage at the blockage point, it is determined whether to continue moving the unblocking device until the blockage in the oil and gas pipeline 6 is completely cleared.

[0038] The unblocking device for wax or hydrate blockages in oil and gas pipelines of the present invention utilizes a conical structure with the guide head 2 opening towards the main body 1. By activating the agent pump 4, chemical agents are injected into the injection pipe 3, causing the chemical agents to be sprayed out from the injection holes 5 on the injection pipe 3. The liquid jet acts on the guide head 2, pushing the unblocking device along the pipeline to the blockage location, thus facilitating the delivery of the chemical agents to the blockage point. This effectively removes wax or hydrate blockages in oil and gas pipelines. The device is simple to operate and significantly reduces unblocking costs and time compared to conventional unblocking methods, showing promising application prospects.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for unblocking wax or hydrate blockages in oil and gas pipelines, characterized in that: The unblocking device includes a main body, a guide head, and a spray pipe. The guide head is located above the main body and has a tapered structure with its opening facing the main body. The spray pipe passes through the main body and its top end is connected to the guide head. The bottom end of the spray pipe is used to connect to a chemical pump. There is a buffer gap between the guide head and the main body, and the spray pipe has several spray holes on its body located in the buffer gap. The flow guide head includes a first side plate and a second side plate, which are integrally formed and set at an angle. The top end of the first side plate and the second side plate connected together constitutes the tip of the flow guide head, and the bottom end of the first side plate and the second side plate away from each other constitutes the opening end of the flow guide head. The injection pipe is arranged along the central axis of the flow guide head. The inner side of the flow guide head is provided with a first fixed baffle. One end of the first fixed baffle is fixed to the inner side plate of the first side plate, and the other end of the first fixed baffle is fixed to the inner side plate of the second side plate. A through hole for the spray pipe to pass through is opened in the middle of the first fixed baffle, and a limit plate is fixed to the end of the spray pipe located above the first fixed baffle. The inner side of the flow guide head is provided with a second fixed baffle horizontally above the first fixed baffle. One end of the second fixed baffle is fixed to the inner side plate of the first side plate, and the other end of the second fixed baffle is fixed to the inner side plate of the second side plate. There is a gap between the second fixed baffle and the first fixed baffle for the flow guide head to float up and down.

2. The device for unblocking wax or hydrate blockages in oil and gas pipelines according to claim 1, characterized in that: The included angle between the first side plate and the second side plate is less than or equal to 90°.

3. The device for unblocking wax or hydrate blockages in oil and gas pipelines according to claim 2, characterized in that: The main body has a columnar structure, and the diameter of the open end of the guide head is the same as the diameter of the main body.

4. The device for unblocking wax or hydrate blockages in oil and gas pipelines according to claim 3, characterized in that: The bottom of the main body has an arc-shaped round bottom structure.

5. A method for unblocking oil and gas pipelines with wax or hydrate blockages, comprising the unblocking device for oil and gas pipelines with wax or hydrate blockages as described in any one of claims 1-4, characterized in that, The method includes: Based on the pipe diameter and local curvature radius of the blocked oil and gas pipeline, select a deblocking device with appropriate diameter and length, and select a chemical delivery hose of appropriate length and diameter and a matching chemical pump based on the location of the blockage point in the oil and gas pipeline and the required flow rate of the injected agent. Place the unblocking device into the blocked oil and gas pipeline, start the chemical pump to make the unblocking device run along the pipeline under the action of chemical reaction force, and adjust the flow rate of the chemical pump according to the running resistance of the unblocking device to adjust the movement speed of the unblocking device. After the unblocking device reaches the blockage point, the agent is continuously injected and left to stand for a set time. Then, the unblocking device is moved continuously based on the decomposition of the blockage at the blockage point until the blockage in the oil and gas pipeline is completely cleared.

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