Gas pipeline heat preservation system

Abstract

The utility model relates to the field of high-pressure natural gas conveying pipelines, and discloses a gas pipeline heat preservation system which is arranged on the periphery of a conveying pipeline and comprises a heating layer, a heat preservation layer and a sealing sleeve, a heating pipe is arranged in the heating layer and tightly attached to the conveying pipeline, and the heating layer comprises a second heating area and a first heating area right opposite to an icing position on the conveying pipeline. The heat preservation layer comprises first heat insulation areas and second heat insulation areas which are integrally arranged, the second heat insulation areas are located on the periphery of the heating layer, the two first heat insulation areas are located at the two ends of the heating layer respectively, and the two second heat insulation areas are located at the two ends of the heating layer respectively. The heat preservation layer completely wraps the heating layer, and the sealing sleeve completely wraps the heat preservation layer. According to the utility model, the heating layer for segmented heating is arranged at the easy-to-freeze part of the conveying pipeline, and the thermal insulation layer is arranged outside the heating layer, so that the pipeline has the advantages of simple structure, uniform heating, excellent thermal insulation effect and the like, and the pipeline is effectively prevented from being frozen and blocked.

Description

Technical Field

[0001] The utility model relates to the technical field of high-pressure natural gas transmission pipelines, in particular to a gas pipeline heat preservation system. Background Technique

[0002] Liquefied Natural Gas (LNG) is recognized as the cleanest fossil energy on earth. The manufacturing process of liquefied natural gas involves the purification of natural gas, including the removal of impurities such as carbon dioxide, sulfides, hydrocarbons, water, etc., and then cooling the gaseous natural gas under normal pressure to -162 °C to condense it into a liquid state. The volume of liquefied natural gas is about 1 / 625 of the volume of the same amount of gaseous natural gas. Therefore, ultra-low temperature and normal pressure liquefaction of natural gas can greatly save storage and transportation space, and the liquefied natural gas can be re-vaporized during use.

[0003] Although the manufacturing process of liquefied natural gas includes its purification treatment, there are still inevitably a small amount of water vapor, carbon dioxide, nitrogen, etc. doped in the finished natural gas. These impurity components will have an adverse impact on the subsequent production and transportation of natural gas. Taking water vapor as an example, since the density of water is greater than that of natural gas, more water is likely to accumulate at the horizontal low points of the high-pressure natural gas transmission pipelines and the bottoms of vertical channels in natural gas stations during long-term use. When the external temperature drops below 0 °C in winter, or at the throttling part of the high-pressure natural gas transmission pipeline, a small amount of water in the high-pressure natural gas transmission pipeline will turn into ice crystals. And at the horizontal low points and other positions where water is likely to accumulate in the high-pressure natural gas transmission pipeline, it will directly freeze to form ice blocks, directly causing the blockage of the natural gas transmission pipeline. Therefore, how to deal with the problem of water accumulation and icing in the high-pressure natural gas transmission pipeline is the key measure to solve the pipeline blockage problem. Content of the Utility Model

[0004] Aiming at the problem existing in the prior art: the accumulated water in the high-pressure natural gas transmission pipeline freezes when the external temperature drops, which is likely to cause pipeline blockage. The purpose of the utility model is to provide a gas pipeline heat preservation system, which sets a segmented heating layer at the easy-to-freeze part of the transmission pipeline and sets a heat preservation layer outside the heating layer, with the advantages of simple structure, uniform heating, excellent heat preservation effect, etc., and effectively prevents the pipeline from icing and blocking.

[0005] To achieve the above purpose, the technical solution of the utility model is as follows:

[0006] A gas pipeline insulation system is arranged around the conveying pipeline and includes a heating layer, a heat insulation layer, and a sealing sleeve. A heating pipe capable of generating heat is arranged in the heating layer, and the heating layer is closely attached to the conveying pipeline. The heating layer includes a first heating area and a second heating area integrally arranged. The first heating area faces the icing position on the conveying pipeline, and the two second heating areas are respectively arranged at both ends of the first heating area. The density of the heating pipes in the first heating area is greater than that in the second heating area. The heat insulation layer includes a first heat insulation area and a second heat insulation area integrally arranged. The second heat insulation area is arranged on the periphery of the heating layer, and the two first heat insulation areas are respectively arranged at both ends of the heating layer and the first heat insulation area is closely attached to the conveying pipeline. The heat insulation layer completely wraps the heating layer, and the sealing sleeve completely wraps the heat insulation layer.

[0007] The present utility model is further configured such that the density of the heating pipes in the first heating area is twice that of the heating pipes in the second heating area.

[0008] The present utility model is further configured such that the heating layer further includes a heat conducting sleeve and an isolation sleeve. The heat conducting sleeve is closely attached to the conveying pipeline, and the isolation sleeve is inserted and matched with the end of the heat conducting sleeve to form a cavity for accommodating the heating pipes. The heating pipes are wound and fixed around the periphery of the heat conducting sleeve.

[0009] The present utility model is further configured such that a first connection head is arranged at the end of the heat conducting sleeve, a second connection head is arranged at the end of the isolation sleeve, and the first connection head and the second connection head are engaged with each other.

[0010] The present utility model is further configured such that the isolation sleeve is made of polyethylene material.

[0011] The present utility model is further configured such that the heat conducting sleeve is made of metal material.

[0012] The present utility model is further configured such that a first temperature sensor for detecting the temperature of the first heating area and a second temperature sensor for detecting the temperature of the second heating area are arranged in the cavity formed by the isolation sleeve and the heat conducting sleeve.

[0013] The present utility model is further configured to further include a controller for controlling the heating time of the heating pipes. The first temperature sensor and the second temperature sensor are both electrically connected to the controller.

[0014] The present utility model is further configured such that the temperature range of the second heating area is 10 - 30 degrees Celsius, and the temperature range of the first heating area is 10 - 50 degrees Celsius.

[0015] The present utility model is further configured such that the sealing sleeve is made of stainless steel material, and the heat insulation layer is made of heat insulation cotton.

[0016] In summary, the beneficial effects achieved by the present utility model are as follows:

[0017] (1) The heating layer is closely attached to the conveying pipeline. Therefore, when the heating pipes in the heating layer generate heat, the heat can be quickly conducted to the conveying pipeline to melt the ice crystals in the conveying pipeline or prevent ice formation in the conveying pipeline. At the same time, the heat insulation layer wrapping the heating layer isolates the heat exchange between the space where the heating layer is located and the external environment to a certain extent, greatly reducing the loss of heat generated by the heating layer and delaying the influence of the external temperature on the conveying pipeline wrapped by the heating layer. The sealing sleeve outside the heat insulation layer provides strict protection for the heating layer and the heat insulation layer, preventing the external environment from damaging the heat insulation layer and the heating layer;

[0018] (2) The heating layer is provided with three heating zones in total, namely the first heating zone facing the ice formation position on the conveying pipeline and two second heating zones respectively arranged at both ends of the first heating zone. Moreover, the density of the heating pipes in the first heating zone is greater than that in the second heating zone. This setting not only makes the heating at the ice formation position of the conveying pipeline more uniform, preventing a large temperature difference at local positions on the conveying pipeline from causing large stress inside the conveying pipeline and shortening the service life, but also can further enhance the overall ice melting or ice prevention ability of the heating layer, avoiding the blockage caused by the steam generated by the heating at the ice formation position on the conveying pipeline from condensing again when encountering cold near the conveying pipeline;

[0019] (3) The heating layer is formed by inserting a separation sleeve made of polyethylene material and a heat conduction sleeve made of metal material. The heat conduction sleeve has high heat conduction efficiency and is closely attached to the conveying pipeline, so as to quickly transfer the heat generated by the heating pipes to the conveying pipeline. The separation sleeve has poor heat conduction performance, which can prevent the heat generated by the heating pipes from affecting the heat insulation layer and also has the effect of preventing heat conduction to the heat insulation layer and causing heat loss;

[0020] (4) The temperature sensors arranged in the heating layer can detect the temperatures of different heating zones in real time and transmit signals to the controller. The controller receives the signals and controls the heating time of the heating pipes according to the preset logic, controlling the temperature range of the second heating zone to be 10 - 30 degrees Celsius and the temperature range of the first heating zone to be 10 - 50 degrees Celsius, realizing automatic control. Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model, the following will briefly introduce the drawings required to be used in the specification. Obviously, the drawings described below are only some embodiments recorded in the present utility model. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0022] Figure 1 Schematic cross-sectional structure of the gas pipeline heat insulation system in the present utility modelFigure 1 ;

[0023] Figure 2 This is a schematic cross-sectional structure of the gas pipeline insulation system in the present utility model. Figure 2 ;

[0024] Figure 3 This is a schematic cross-sectional structure of the gas pipeline insulation system in the present utility model. Figure 3 .

[0025] In the figure: 1, conveying pipeline; 2, heating layer; 21, first heating area; 22, second heating area; 3, heat preservation layer; 31, first heat insulation area; 32, second heat insulation area; 4, sealing sleeve; 5, heat conduction sleeve; 51, first connector; 6, isolation sleeve; 61, second connector; 7, heating pipe; 8, first temperature sensor; 9, second temperature sensor. Specific embodiments

[0026] Next, in combination with the accompanying drawings in the embodiments of the present utility model, the technical solutions in the embodiments of the present utility model will be clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present utility model, rather than all of the embodiments. For ease of description, the terms "vertical", "horizontal", "left", "right", "upper", "lower", "inner", "outer", "bottom", etc. used in this specification indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application.

[0027] Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present utility model.

[0028] As shown in the attached Figure 1 attachment Figure 2 attachment Figure 3 and the attached

[0029] A gas pipeline insulation system is provided on the periphery of the conveying pipeline 1 and includes a heating layer 2, a heat preservation layer 3 and a sealing sleeve 4.

[0030] The heating layer 2 is in close contact with the conveying pipeline 1, and the conveying pipeline 1 is usually made of seamless steel pipe. The heating layer 2 includes a heat conduction sleeve 5, an isolation sleeve 6 and a heating pipe 7.

[0031] The first connector 51 has an annular structure, and its diameter is larger than that of the heat-conducting sleeve 5. Therefore, an annular groove is formed between the first connector 51 and the outer wall of the heat-conducting sleeve 5.

[0032] The heat-conducting sleeve 5 is made of a metal material with excellent heat-conducting performance. In this embodiment, the heat-conducting sleeve 5 can be made of aluminum material, and the inner wall of the heat-conducting sleeve 5 closely adheres to the outer wall of the conveying pipeline 1.

[0033] The isolation sleeve 6 has a cylindrical tubular structure and is horizontally arranged. It is made of polyethylene material.

[0034] Polyethylene (abbreviation: PE) is a thermoplastic plastic in the prior art. It has good elasticity, flexibility and low stiffness, and can withstand large deformations without breaking. At the same time, polyethylene is a plastic with low thermal conductivity and low heat conduction characteristics. Its thermal conductivity is much lower than that of traditional materials such as metals and ceramics. And it has excellent low-temperature resistance, and the service temperature range is between -70 degrees Celsius and 80 degrees Celsius.

[0035] At both ends of the isolation sleeve 6, second connectors 61 integrally provided with the isolation sleeve 6 are respectively arranged. The second connector 61 has an annular structure, and its diameter is smaller than that of the isolation sleeve 6. And the shape and size of the second connector 61 are both adapted to those of the first connector 51, and the two can be engaged with each other. Therefore, by applying an external force to slightly deform the isolation sleeve 6 and the second connector 61, the plug-in fit between the first connector 51 and the second connector 61 can be completed, so that a closed cavity for accommodating the heating pipe 7 is formed between the isolation sleeve 6 and the heat-conducting sleeve 5.

[0036] In this embodiment, the heating pipe 7 is an electric heating pipe and can generate heat when powered on. The heating pipe 7 is wound and fixed around the heat-conducting sleeve 5 and closely adheres to the heat-conducting sleeve 5 to uniformly transfer the heat to the conveying pipeline 1 through the heat-conducting sleeve 5.

[0037] The closed cavity formed between the isolation sleeve 6 and the heat-conducting sleeve 5 can be divided into a first heating area 21 and a second heating area 22 which are integrally provided.

[0038] The first heating area 21 is opposite to the ice-prone position on the conveying pipeline 1, and the two second heating areas 22 are respectively arranged at both ends of the first heating area 21. And the density of the heating pipe 7 in the first heating area 21 is greater than that of the heating pipe 7 in the second heating area 22. In this embodiment, the density of the heating pipe 7 in the first heating area 21 is twice that of the heating pipe 7 in the second heating area 22.

[0039] When the heating pipe 7 is energized and generates heat, since a large amount of heat is rapidly generated in the first heating zone 21, the temperature of the conveying pipeline 1 wrapped by the first heating zone 21 rises rapidly. To prevent excessive local temperature difference on the conveying pipeline 1 from causing large stress inside the conveying pipeline 1 and shortening its service life, and at the same time make the heated area at the ice-covered position of the conveying pipeline 1 more uniform, it is necessary to make the second heating zones 22 at both ends of the first heating zone 21 work and generate heat while the first heating zone 21 is working and generating heat. This can not only further enhance the overall ice melting or anti-icing ability of the heating layer 2, but also prevent the water vapor generated by heating at the ice-covered position on the conveying pipeline 1 from condensing again when it meets cold near the conveying pipeline 1 and causing blockage.

[0040] In this embodiment, the heat insulation layer 3 is made of heat insulation cotton. The heat insulation layer 3 can be divided into a first heat insulation zone 31 and a second heat insulation zone 32 which are integrally arranged.

[0041] The second heat insulation zone 32 is arranged on the periphery of the heating layer 2. The isolation sleeve 6 made of polyethylene material has poor thermal conductivity, which can prevent the heat generated by the heating pipe 7 from affecting the heat insulation layer, and at the same time also has the effect of preventing heat from being conducted to the heat insulation layer 3 and causing heat loss.

[0042] The two first heat insulation zones 31 are respectively arranged at both ends of the heating layer 2 and the first heat insulation zone 31 is in close contact with the conveying pipeline 1, so that the heat insulation layer 3 completely wraps the heating layer 2. The tight wrapping of the heat insulation layer 3 isolates the heat exchange between the space where the heating layer 2 is located and the external environment to a certain extent, greatly reduces the loss of heat generated by the heating layer 2, and delays the influence of the external temperature on the conveying pipeline 1 wrapped by the heating layer 2.

[0043] The sealing sleeve 4 completely wraps the heat insulation layer 3, thus providing a tight protection for the heating layer 2 and the heat insulation layer 3 to prevent the external environment from damaging the heat insulation layer 3 and the heating layer 2. In this embodiment, the sealing sleeve 4 is made of stainless steel material, and preferably 304 stainless steel.

[0044] The gas pipeline heat insulation system in the present utility model further includes a first temperature sensor 8 for detecting the temperature of the first heating zone 21, a second temperature sensor 9 for detecting the temperature of the second heating zone 22, and a controller for controlling the heating time of the heating pipe 7.

[0045] The first temperature sensor 8 and the two second temperature sensors 9 are both arranged in the cavity formed by the isolation sleeve 6 and the heat conducting sleeve 5, and the first temperature sensor 8 and the second temperature sensor 9 are both electrically connected to the controller. The temperature sensors detect the temperature of different heating zones in real time and transmit the signals to the controller. The controller receives the signals and controls the energization and heating time of the heating pipe 7 according to the preset logic.

[0046] The utility model selects a common industrial controller in the prior art, such as a PLC (programmable logic controller). Without involving the improvement of the control logic algorithm, the temperature range of the second heating zone 22 can be controlled within 10 - 30 degrees Celsius, and at the same time, the temperature range of the first heating zone 21 can be controlled within 10 - 50 degrees Celsius, realizing automatic control.

[0047] The implementation principle of the above embodiment is as follows:

[0048] When the second temperature sensor 9 or the first temperature sensor 8 detects that the temperature in the heating layer 2 is lower than 10 degrees Celsius, the controller controls the heating tube 7 to be energized and start heating. The heat conduction sleeve 5 in the heating layer 2 has high heat conduction efficiency and is closely attached to the conveying pipeline 1. Therefore, the heat generated when the heating tube 7 heats up can be quickly conducted to the conveying pipeline 1. A large amount of heat is quickly generated in the first heating zone 21, and the second heating zone 22 works simultaneously to melt the ice crystals in the conveying pipeline 1 or prevent the conveying pipeline 1 from freezing. The heat insulation layer 3 greatly reduces the loss of heat generated by the heating layer 2, can reduce the working frequency of the heating tube 7, and thus reduces the energy consumption of the heat insulation system.

[0049] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications once they know the basic creative concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications falling within the scope of the present invention. Obviously, those skilled in the art can make various changes and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims

1. A gas pipeline heat insulation system is arranged around a conveying pipeline (1), and is characterized in that, It includes a heating layer (2), a heat-insulating layer (3) and a sealing sleeve (4). A heating pipe (7) capable of generating heat is arranged in the heating layer (2), and the heating layer (2) is closely attached to the conveying pipeline (1). The heating layer (2) includes a first heating area (21) and a second heating area (22) which are integrally arranged. The first heating area (21) faces the icing position on the conveying pipeline (1). The two second heating areas (22) are respectively arranged at both ends of the first heating area (21). The density of the heating pipes (7) in the first heating area (21) is greater than that of the heating pipes (7) in the second heating area (22). The heat-insulating layer (3) includes a first heat-insulating area (31) and a second heat-insulating area (32) which are integrally arranged. The second heat-insulating area (32) is arranged on the periphery of the heating layer (2). The two first heat-insulating areas (31) are respectively arranged at both ends of the heating layer (2) and the first heat-insulating area (31) is closely attached to the conveying pipeline (1). The heat-insulating layer (3) completely wraps the heating layer (2), and the sealing sleeve (4) completely wraps the heat-insulating layer (3).

2. The gas pipeline heat preservation system according to claim 1, wherein The density of the heating pipes (7) in the first heating area (21) is twice that of the heating pipes (7) in the second heating area (22).

3. The gas pipeline insulation system according to claim 1, characterized in that, The heating layer (2) further includes a heat-conducting sleeve (5) and an isolation sleeve (6). The heat-conducting sleeve (5) is closely attached to the conveying pipeline (1). The isolation sleeve (6) is inserted and matched with the end of the heat-conducting sleeve (5) to form a cavity for accommodating the heating pipe (7). The heating pipe (7) is wound and fixed on the periphery of the heat-conducting sleeve (5).

4. The gas pipeline heat preservation system according to claim 3, wherein A first connector (51) is arranged at the end of the heat-conducting sleeve (5), and a second connector (61) is arranged at the end of the isolation sleeve (6). The first connector (51) and the second connector (61) are engaged with each other.

5. The gas pipeline insulation system according to claim 4, characterized in that, The isolation sleeve (6) is made of polyethylene material.

6. The gas pipeline heat preservation system according to claim 4, characterized in that, The heat-conducting sleeve (5) is made of metal material.

7. The gas pipeline heat preservation system according to claim 3, characterized in that A first temperature sensor (8) for detecting the temperature of the first heating area (21) and a second temperature sensor (9) for detecting the temperature of the second heating area (22) are arranged in the cavity formed by the isolation sleeve (6) and the heat-conducting sleeve (5).

8. The gas pipeline heat preservation system according to claim 7, characterized in that, It also includes a controller for controlling the heating time of the heating pipe (7). The first temperature sensor (8) and the second temperature sensor (9) are both electrically connected to the controller.

9. The gas pipeline heat preservation system according to claim 8, wherein, The temperature range of the second heating area (22) is 10 - 30 degrees Celsius, and the temperature range of the first heating area (21) is 10 - 50 degrees Celsius.

10. The gas pipeline heat preservation system according to claim 1, characterized in that, The sealing sleeve (4) is made of stainless steel material, and the heat-insulating layer (3) is made of heat-insulating cotton.

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