Submarine pipeline steam conveying system

Abstract

The utility model discloses a submarine pipeline steam conveying system which comprises a steam conveying pipeline, and the steam conveying pipeline comprises a working inner pipe, a protective outer pipe and a heat preservation structure arranged between the working inner pipe and the protective outer pipe. The heat preservation structure comprises an inner heat preservation layer, a first reflecting layer and an outer heat preservation layer which are sequentially arranged on the outer side face of the working inner pipe from inside to outside, and an air layer is formed between the inner side face of the protective outer pipe and the outer heat preservation layer; an anti-corrosion layer is arranged on the outer surface of the protective outer pipe, the steam conveying pipeline is of a pipeline form that a heat preservation structure is embedded in a double-layer sleeve, the heat dissipating capacity of the pipeline is reduced, a better heat preservation effect is obtained, and economical efficiency can be considered under the condition that the heat dissipating capacity is guaranteed by means of the heat preservation structure and an air layer. Even if the thermal insulation structure is broken, seawater cannot be in direct contact with the working inner pipe due to the protection of the protective outer pipe, so that the safety of the working inner pipe is ensured. The requirements of the steam pipeline and the marine environment can be met, and the steam conveying pipeline can be laid on the seabed.

Description

Technical Field

[0001] This utility model relates to the field of submarine pipeline technology, and in particular to a submarine pipeline steam transport system. Background Technology

[0002] Currently, nuclear power plant steam supply pipelines mainly use burial on land to supply steam. However, since nuclear power plant sites are all located along the coast with many surrounding bays, burial on land inevitably requires laying steam pipelines around these bays, resulting in excessively long routes that affect terminal parameters and increase project investment. Using subsea pipelines to directly cross bays could significantly reduce the route length. However, current steam supply pipelines cannot be directly used for subsea laying; there are no existing application records for subsea steam supply pipelines, and related research information is extremely limited, essentially leaving the field blank.

[0003] Currently, steam supply pipelines mainly come in two forms: overhead and underground. A typical structural form of underground steam supply pipelines is shown below. Figure 1 The buried steam supply pipeline mainly includes a working steel pipe 100 and an insulation layer 200 and an anti-corrosion layer 300 located outside the working steel pipe 100.

[0004] Currently, buried steam pipelines used on land cannot be directly applied to transport steam underwater for the following reasons:

[0005] 1) Existing land-based buried steam supply pipelines use single-layer pipelines. If the pipeline uses the materials commonly used for land-based buried steam supply pipelines, it cannot adapt to the seabed environment. If the anti-corrosion layer 300 fails, there is a risk of rapid corrosion. If the pipeline uses the materials commonly used for submarine pipelines, since there is currently no practical application of the commonly used materials for submarine pipelines in high-temperature steam, it cannot be guaranteed that the pipeline can operate normally for a long time.

[0006] 2) The existing buried steam supply pipelines on land use insulation methods. If the insulation layer is broken, seawater will come into direct contact with the working steel pipe 100, causing the insulation to fail.

[0007] 3) Existing buried steam supply pipelines on land only rely on coatings and other methods for corrosion protection, which cannot adapt to the seabed environment and poses a risk of corrosion failure. Utility Model Content

[0008] The technical problem to be solved by this utility model is to provide a submarine pipeline steam transport system.

[0009] The technical solution adopted by this utility model to solve its technical problem is as follows: a subsea pipeline steam transportation system is constructed, including a steam transportation pipeline, the steam transportation pipeline including a working inner pipe, a protective outer pipe and a heat insulation structure disposed between the working inner pipe and the protective outer pipe; the heat insulation structure includes an inner heat insulation layer, a first reflective layer and an outer heat insulation layer disposed sequentially from the inside to the outside on the outer side of the working inner pipe, an air layer is formed between the inner side of the protective outer pipe and the outer heat insulation layer; the outer surface of the protective outer pipe is provided with an anti-corrosion layer.

[0010] In some embodiments, both the inner insulation layer and the outer insulation layer include an aerogel insulation layer; or, the inner insulation layer includes an aerogel insulation layer and the outer insulation layer includes a polyurethane insulation layer.

[0011] In some embodiments, the first reflective layer comprises an aluminum foil reflective layer.

[0012] In some embodiments, the anti-corrosion layer comprises a three-layer polyethylene composite anti-corrosion layer.

[0013] In some embodiments, the subsea pipeline steam transport system further includes an anchor, the anchor having a ring-shaped structure, and the inner wall of the anchor being fixedly connected to the outer wall of the working inner pipe.

[0014] One end of the protective outer tube and the thermal insulation structure along their length is fixedly connected to the end face of the anchor.

[0015] In some embodiments, the subsea pipeline steam transport system includes a temperature and humidity detection device disposed on the insulation structure.

[0016] In some embodiments, the subsea pipeline steam transport system includes a pressure sensor disposed within the insulation structure.

[0017] In some embodiments, the subsea pipeline steam transport system further includes a cathodic protection device installed on the outer surface of the anti-corrosion layer.

[0018] In some embodiments, the cathodic protection device includes a first semi-ring and a second semi-ring that are detachably connected.

[0019] In some embodiments, the working inner tube comprises a chromium-molybdenum steel tube.

[0020] The present invention offers the following advantages: The steam transport pipeline of this subsea pipeline steam transport system adopts a double-layered sleeve with an embedded insulation structure. By utilizing the combined effects of reducing heat radiation and heat conduction, it reduces heat loss from the pipeline, achieving better insulation. The insulation structure and air layer ensure both adequate heat dissipation and economic efficiency. Furthermore, because the insulation structure is located between the inner working pipe and the outer protective pipe, even if the insulation structure ruptures, the outer protective pipe prevents seawater from directly contacting the inner working pipe, ensuring its safety. This design satisfies both the requirements of steam pipelines and the requirements of the marine environment, allowing the steam transport pipeline to be laid on the seabed. Attached Figure Description

[0021] To more clearly illustrate the technical solution of this utility model, the present utility model will be further described below in conjunction with the accompanying drawings and embodiments. It should be understood that the following drawings only show some embodiments of this utility model and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort. In the drawings:

[0022] Figure 1 This is a simplified structural diagram of a land-based buried steam supply pipeline based on related technologies.

[0023] Figure 2 This is a schematic diagram of the structure of a subsea pipeline steam transport system in some embodiments of this utility model;

[0024] Figure 3 This is a schematic diagram of the steam conveying pipeline in some embodiments of this utility model;

[0025] Figure 4 This is a schematic diagram of the structure of the cathodic protection device in some embodiments of this utility model. Detailed Implementation

[0026] To provide a clearer understanding of the technical features, objectives, and effects of this utility model, the specific embodiments of this utility model are now described in detail with reference to the accompanying drawings. In the following description, it should be understood that the orientations or positional relationships indicated by terms such as "front," "rear," "upper," "lower," "left," "right," "longitudinal," "horizontal," "vertical," "horizontal," "top," "bottom," "inner," "outer," "head," and "tail" are based on the orientations or positional relationships shown in the accompanying drawings, and are constructed and operated in a specific orientation. They are only for the convenience of describing this technical solution and do not indicate that the device or component referred to must have a specific orientation; therefore, they should not be construed as limitations on this utility model.

[0027] It should also be noted that, unless otherwise explicitly specified and limited, terms such as "installation," "connection," "joining," "fixing," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. When an component is referred to as being "on" or "below" another component, the component can be located "directly" or "indirectly" on the other component, or there may be one or more intermediary components. The terms "first," "second," "third," etc., are only for the convenience of describing this technical solution and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first," "second," "third," etc., may explicitly or implicitly include one or more of that feature. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0028] In the following description, specific details such as particular system structures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the present invention. However, those skilled in the art will understand that the present invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

[0029] See Figures 2 to 4 This utility model discloses a subsea pipeline steam transport system, which includes a steam transport pipeline 10. The steam transport pipeline 10 includes a working inner pipe 11, a protective outer pipe 12, and a heat insulation structure disposed between the working inner pipe 11 and the protective outer pipe 12. The heat insulation structure includes an inner heat insulation layer 13, a first reflective layer 14, and an outer heat insulation layer 15 disposed sequentially from the inside to the outside on the outer side of the working inner pipe 11. An air layer 16 is formed between the inner side of the protective outer pipe 12 and the outer heat insulation layer 15. The outer surface of the protective outer pipe 12 is provided with an anti-corrosion layer 17.

[0030] In some embodiments, at least one second reflective layer is provided between the inner working tube 11 and the inner insulation layer 13. The second reflective layer may be an aluminum foil reflective layer, such as, but not limited to, aluminum foil reflective cloth. Of course, the second reflective layer may not be provided between the inner working tube 11 and the inner insulation layer 13, and no specific limitation is made here.

[0031] In some embodiments, both the inner insulation layer 13 and the outer insulation layer 15 include an aerogel insulation layer, such as, but not limited to, aerogel felt. Preferably, the inner insulation layer 13 and the outer insulation layer 15 can be silica aerogel insulation layers. Alternatively, the inner insulation layer 13 includes an aerogel insulation layer, and the outer insulation layer 15 includes a polyurethane insulation layer, wherein the aerogel insulation layer can be, but not limited to, aerogel felt. That is, the inner insulation layer 13 can be made of aerogel material, and the outer insulation layer 15 can be made of polyurethane material.

[0032] In some embodiments, the first reflective layer 14 includes an aluminum foil reflective layer, such as, but not limited to, aluminum foil reflective fabric. The inner insulation layer 13, the first reflective layer 14, and the outer insulation layer 15 together form a multilayer composite insulation layer.

[0033] In some embodiments, the air layer 16 is defined by the gap between the inner side of the protective outer tube 12 and the outer insulation layer 15. The air layer 16 does not flow and has a low thermal conductivity, thus enhancing the heat insulation effect.

[0034] In some embodiments, the anti-corrosion layer 17 comprises a three-layer polyethylene composite structure anti-corrosion layer. The anti-corrosion layer 17 uses a three-layer polyethylene composite structure anti-corrosion layer, namely 3LPE, and its structural composition is as follows: First layer: epoxy powder (FBE), typically thicker than 100 micrometers, directly bonded to the steel pipe surface, providing good chemical corrosion resistance and cathodic disbondment resistance. Second layer: adhesive (AD), with a thickness between 170 and 250 micrometers, ensuring good adhesion between the epoxy powder layer and the polyethylene layer. Third layer: polyethylene (PE), with a thickness between 2.5 and 3.7 millimeters, providing mechanical protection and exhibiting good chemical stability and corrosion resistance. Through the combined action of these three layers, a robust protective layer is formed, effectively isolating the outer protective pipe 12 from contact with the surrounding environment and preventing corrosion and wear.

[0035] Understandably, this three-layer polyethylene composite anti-corrosion layer has good corrosion resistance, water vapor permeability resistance and mechanical properties, and can adapt to different environmental conditions, such as high temperature, low temperature and chemical corrosion environments.

[0036] Understandably, the steam transmission pipe 10 of this subsea pipeline steam transmission system adopts a double-layered sleeve with an embedded insulation structure. By utilizing the combined effects of reducing heat radiation and heat conduction, the heat loss of the pipe is reduced, resulting in better insulation. The insulation structure and air layer 16 allow for both energy efficiency and reduced heat loss. Furthermore, since the insulation structure is located between the inner working pipe 11 and the outer protective pipe 12, even if the insulation structure ruptures, the outer protective pipe 12 prevents seawater from directly contacting the inner working pipe 11, ensuring the safety of the inner working pipe 11.

[0037] like Figure 2 As shown, the subsea pipeline steam transport system also includes an anchor 20, which has a ring-shaped structure. The inner wall of the anchor 20 is fixedly connected to the outer wall of the working inner pipe 11, such as by welding. One end of the protective outer pipe 12 and one end of the insulation structure along their length are fixedly connected to the end face of the anchor 20, such as by welding. The working inner pipe 11 is made of chromium-molybdenum steel, the protective outer pipe 12 is made of X65 steel, and the anchor 20 can be made of chromium-molybdenum steel. The three can be effectively welded together. Of course, the working inner pipe 11 can also be made of other types of high-quality steel that match the steam temperature and pressure, and the protective outer pipe 12 can be made of other types of steel that are suitable for the seabed environment. No specific limitations are made here.

[0038] Understandably, the protective outer pipe 12 and the insulation structure can be separated into independent pipe sections by the anchor 20. Even if the protective outer pipe 12 breaks, the broken section will only be affected by the segmented isolation measures, and maintenance will only require replacing a section of the pipe.

[0039] In some embodiments, the subsea pipeline steam transport system includes a temperature and humidity detection device 30 disposed on the insulation structure. Preferably, the temperature and humidity detection device 30 can be installed inside the air layer 16 or on the outer insulation layer 15. Understandably, the temperature and humidity detection device 30 determines whether the inner working pipe 11 is leaking by detecting temperature anomalies within the insulation structure, and determines whether the outer protective pipe 12 is leaking by detecting humidity anomalies, thus ensuring timely detection and location of pipeline damage, and timely control of the impact of anomalies through the anchor 20. The temperature and humidity detection device 30 can communicate with the onshore system via a wired method (including armored cables, etc.) or a wireless method (including wireless communication).

[0040] In some embodiments, the subsea pipeline steam transport system includes a pressure sensor 40 disposed within the insulation structure. Preferably, the pressure sensor 40 may be installed within the air layer 16 or on the outer insulation layer 15.

[0041] like Figure 2 and Figure 4 As shown, in some embodiments, the subsea pipeline steam transport system further includes a cathodic protection device 50, which is installed on the outer surface of the anti-corrosion layer 17.

[0042] In some embodiments, the cathodic protection device 50 includes a first semi-ring 51 and a second semi-ring 52 that are detachably connected. The first semi-ring 51 has first connecting ears 511 at both ends in the arc direction, and the second semi-ring 52 has second connecting ears 521 at both ends in the arc direction. A fastening bolt 53 passes through the first connecting ears 511 and the second connecting ears 512 and is connected and fixed to a fastening nut 54 to fix the cathodic protection device 50 to the steam conveying pipeline 10. Of course, the cathodic protection device 50 can also use other structural forms, which are not specifically limited here. In some embodiments, the cathodic protection device 50 may employ an aluminum-zinc-indium alloy for cathodic protection.

[0043] Understandably, unlike traditional steam transmission pipelines which only rely on coatings for corrosion protection, this application incorporates a cathodic protection device 50 along with an anti-corrosion layer 17 in the steam transmission pipeline 10, thereby increasing electrochemical corrosion protection measures to adapt to the seabed environment. In some embodiments, the steam transmission pipeline 10 may further include a concrete counterweight layer disposed on the outer surface of the anti-corrosion layer 17, in which case the cathodic protection device 50 is installed on the outer surface of the concrete counterweight layer.

[0044] Table 1 below shows the hydraulic calculation results for different insulation structure thicknesses (3.1 MPaA, starting from 270℃).

[0045] Table 1

[0046]

[0047] Based on calculations, at a pressure of 3.1 MPaA and a starting temperature of 270℃, with an insulation thickness of 70mm, the temperature drop is 2℃ / km, and there is no liquid phase precipitation during transport; the pipeline terminus remains superheated steam. Considering a certain margin in engineering practice, a insulation thickness of 75mm is recommended. Of course, the thickness and materials of this insulation structure and the anti-corrosion layer 17 can be adjusted appropriately according to actual needs; no specific limitations are made here.

[0048] Understandably, this subsea pipeline steam transmission system can directly transport steam across the sea to users, solving problems such as the excessively long route required for laying steam pipelines on land to bypass the bay and the need for land acquisition.

[0049] Unlike traditional single-layer steam pipelines, this subsea steam pipeline system innovatively features a double-layer pipe structure (10). The steam pipeline 10 includes a working inner pipe 11, a protective outer pipe 12, and an insulation structure located between the inner pipe 11 and the outer pipe 12. The inner pipe 11 is in direct contact with the steam, while the outer pipe 12 protects both the inner pipe 11 and the insulation structure, reducing heat loss. This design satisfies both the requirements of a steam pipeline and the requirements of the marine environment, allowing the steam pipeline 10 to be laid on the seabed.

[0050] It is understood that the above embodiments only illustrate preferred embodiments of the present utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present utility model patent. It should be noted that for those skilled in the art, the above technical features can be freely combined, and several modifications and improvements can be made without departing from the concept of the present utility model, all of which fall within the protection scope of the present utility model. Therefore, all equivalent transformations and modifications made within the scope of the claims of the present utility model should fall within the coverage of the claims of the present utility model.

Claims

1. A subsea pipeline steam transport system, characterized in that, The system includes a steam conveying pipe (10), which includes a working inner pipe (11), a protective outer pipe (12), and an insulation structure disposed between the working inner pipe (11) and the protective outer pipe (12). The insulation structure includes an inner insulation layer (13), a first reflective layer (14), and an outer insulation layer (15) disposed sequentially from the inside to the outside of the working inner pipe (11). An air layer (16) is formed between the inner side of the protective outer pipe (12) and the outer insulation layer (15). The outer surface of the protective outer pipe (12) is provided with an anti-corrosion layer (17).

2. The subsea pipeline steam transport system according to claim 1, characterized in that, Both the inner insulation layer (13) and the outer insulation layer (15) include an aerogel insulation layer; or, the inner insulation layer (13) includes an aerogel insulation layer and the outer insulation layer (15) includes a polyurethane insulation layer.

3. The subsea pipeline steam transport system according to claim 1, characterized in that, The first reflective layer (14) includes an aluminum foil reflective layer.

4. The subsea pipeline steam transport system according to claim 1, characterized in that, The anti-corrosion layer (17) includes a three-layer polyethylene composite structure anti-corrosion layer.

5. The subsea pipeline steam transport system according to claim 1, characterized in that, The subsea pipeline steam transport system also includes an anchor (20), which has a ring structure and the inner wall of the anchor (20) is fixedly connected to the outer wall of the working inner pipe (11). The protective outer tube (12) and one end of the thermal insulation structure along their length are fixedly connected to the end face of the anchor (20).

6. The subsea pipeline steam transport system according to claim 1, characterized in that, The subsea pipeline steam transport system includes a temperature and humidity detection device (30) installed on the insulation structure.

7. The subsea pipeline steam transport system according to claim 1, characterized in that, The subsea pipeline steam transport system includes a pressure sensor (40) installed within the insulation structure.

8. The subsea pipeline steam transport system according to claim 1, characterized in that, The subsea pipeline steam transport system also includes a cathodic protection device (50), which is installed on the outer side of the anti-corrosion layer (17).

9. The subsea pipeline steam transport system according to claim 8, characterized in that, The cathodic protection device (50) includes a first semi-ring and a second semi-ring that are detachably connected.

10. The subsea pipeline steam transport system according to any one of claims 1 to 9, characterized in that, The working inner tube (11) includes a chromium-molybdenum steel tube.

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