A device for LNG liquefaction supercooling

Abstract

The utility model provides a kind of for LNG liquefaction supercooling device, including supercooling device main body, the output of supercooling device main body is provided with filter tank, one end of the filter tank is provided with throttle valve, the inner wall of filter tank is equipped with two flower board, multiple filter elements are symmetrically installed between two flower boards, one rotating shaft is rotatably connected in the center of two flower boards, and the rotating shaft is fixedly connected with mounting plate. By setting the front matching structure of multiple filter elements in filter tank and throttle valve, the LNG output by the supercooling device main body can be efficiently filtered, and the accumulation of impurities in the throttle valve core can be improved from the source, reducing the abnormality of valve core opening.

Description

Technical Field

[0001] This utility model relates to the field of natural gas technology, specifically to a subcooling device for LNG liquefaction. Background Technology

[0002] The LNG liquefaction subcooling unit is the core equipment in the natural gas liquefaction and storage process. It mainly works in tandem with the refrigeration unit to cool natural gas to a low-temperature subcooled state, thereby improving the stability of LNG storage and reducing evaporation losses. The compressor, condenser, and throttle valve of the refrigeration unit are responsible for providing a continuous low-temperature environment, while the heat exchanger and subcooler of the liquefaction subcooling unit complete the liquefaction and deep subcooling of natural gas. Together, they achieve efficient LNG production.

[0003] In actual operation, LNG feed gas often carries trace mechanical impurities, such as pipeline rust particles and welding slag. These impurities are prone to accumulate at the valve core of the throttle valve as the medium flows, leading to abnormal valve core opening adjustment, which in turn causes increased fluctuations in subcooled temperature, affecting the quality of LNG products. At the same time, the problem of impurity accumulation requires the throttle valve to be disassembled and cleaned by shutting down the machine. This not only interrupts the normal production process, but also increases the risk of component wear due to frequent disassembly and assembly, reducing the overall operating efficiency of the unit. Utility Model Content

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a solution for LNG liquefaction subcooling devices that addresses the problems mentioned in the background. This invention features a novel structure. By incorporating multiple filter elements within the filter tank and a pre-positioned throttle valve, it efficiently filters impurities from the LNG output by the subcooling unit, preventing rust particles, welding slag, and other impurities in the feed gas from flowing into the throttle valve. This improves the problem of impurity accumulation in the throttle valve core from the source, reducing abnormal valve opening. Furthermore, the switchable filter elements and directional drainage structure allow for impurity removal without complete system shutdown, significantly mitigating production interruptions caused by frequent shutdowns and disassembly, and ensuring continuous and stable operation of the device.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a subcooling device for LNG liquefaction, comprising a subcooling device body, a filter tank at the output end of the subcooling device body, a throttling valve at one end of the filter tank, two perforated plates installed on the inner wall of the filter tank, multiple filter elements symmetrically installed between the two perforated plates, a rotating shaft rotatably fitted at the center of the two perforated plates, an mounting plate fixedly connected to the rotating shaft, cover plates that mate with the upper ends of the filter elements fixedly connected to the lower sides of both ends of the mounting plate, a U-shaped connecting pipe fixedly connected to the lower end of the rotating shaft, a drain pipe fixedly connected to one side of the filter tank, and an installation shell fixedly connected to the upper side of the filter tank, with an adjustment mechanism provided inside the installation shell.

[0006] Furthermore, the output end of the subcooling device body is connected to the input end of the filter tank via a flange, the output end of the filter tank is connected to one end of the throttle valve via a flange, and the upper end of the rotating shaft extends to the upper side of the filter tank.

[0007] Furthermore, the upper end of the U-shaped connector matches the lower end of the filter element, and the U-shaped connector is positioned directly below the cover plate.

[0008] Furthermore, the lower end of the U-shaped connecting pipe is connected to the upper end of the drain pipe via a rotary joint, one end of the drain pipe extends to the outside of the filter tank, and a drain valve is installed at the outer end of the drain pipe.

[0009] Furthermore, the adjustment mechanism includes a circular shell fixedly connected to the upper end of the rotating shaft, a connecting column slidably fitted on the inner wall of the circular shell, a knob cover slidably fitted on the inner wall of the mounting shell, locking blocks fixedly connected to both sides of the knob cover, multiple locking grooves corresponding to the positions of the filter element opened on the inner wall of the mounting shell, and a tension spring sleeved on the outer side of the connecting column.

[0010] Furthermore, the locking block engages with the locking slot, the round shell rotatably fits on the inner wall of the mounting shell, the upper end of the connecting column is fixedly connected to the lower side of the knob cover, and the two ends of the tension spring are fixedly connected to the knob cover and the round shell respectively.

[0011] Furthermore, vertically spaced grooves are formed on both sides of the inner wall of the circular shell, and limiting blocks are fixedly connected to both sides of the connecting column, with the limiting blocks slidingly fitted on the inner wall of the limiting grooves.

[0012] The beneficial effects of this utility model are: 1. This utility model, by setting up a pre-positioned structure for multiple filter elements and a throttle valve in the filter tank, can efficiently filter impurities from the LNG output by the main body of the subcooling unit, preventing impurities such as rust particles and welding slag in the raw gas from flowing to the throttle valve. This improves the problem of impurity accumulation in the throttle valve core from the source, reduces abnormal valve core opening, and, in conjunction with a switchable filter element and a directional drainage structure, allows for the cleaning of impurities without a complete shutdown. This significantly improves the production interruption problem caused by frequent shutdowns and disassemblies, ensuring the continuous and stable operation of the unit.

[0013] 2. This utility model, through the combination of tension spring, locking block and locking groove in the adjustment mechanism, can accurately control the switching and positioning of filter element, and with the limit structure to ensure operational stability, avoid misalignment deviation during filter element switching, improve the accuracy of filter element cleaning and filtration switching, and indirectly improve the impurity filtration effect. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall three-dimensional structure of an LNG liquefaction subcooling device according to the present invention; Figure 2 This is a schematic cross-sectional view of a filter tank for an LNG liquefaction subcooling device according to the present invention. Figure 3 This is a schematic diagram of a U-shaped pipe connection structure for an LNG liquefaction subcooling device according to the present invention; Figure 4 This is a schematic diagram of a knob cover separation structure for an LNG liquefaction subcooling device according to the present invention; Figure 5 This is a schematic cross-sectional view of the mounting shell structure for an LNG liquefaction subcooling device according to the present invention; Figure 6 This utility model relates to a subcooling device for LNG liquefaction. Figure 5 Enlarged structural diagram at point A in the middle; Figure 7 This is a schematic diagram of a rotating shaft connection structure for an LNG liquefaction subcooling device according to the present invention.

[0015] In the diagram: 1. Subcooling unit main body; 2. Filter tank; 3. Throttling valve; 4. Perforated plate; 5. Filter element; 6. Rotary shaft; 7. Mounting plate; 8. Cover plate; 9. U-shaped connecting pipe; 10. Drain pipe; 11. Mounting shell; 12. Adjustment mechanism; 121. Round shell; 122. Connecting column; 123. Knob cover; 124. Locking block; 125. Locking groove; 126. Tension spring; 13. Drain valve; 14. Limiting groove; 15. Limiting block. Detailed Implementation

[0016] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0017] Please refer to Figures 1 to 7This utility model provides a technical solution: a subcooling device for LNG liquefaction, including a subcooling device body 1, a filter tank 2 at the output end of the subcooling device body 1, a throttle valve 3 at one end of the filter tank 2, two perforated plates 4 installed on the inner wall of the filter tank 2, multiple filter elements 5 symmetrically installed between the two perforated plates 4, a rotating shaft 6 rotatably fitted at the center of the two perforated plates 4, an mounting plate 7 fixedly connected to the rotating shaft 6, cover plates 8 that cooperate with the upper end of the filter elements 5 fixedly connected to the lower sides of both ends of the mounting plate 7, a U-shaped connecting pipe 9 fixedly connected to the lower end of the rotating shaft 6, a drain pipe 10 fixedly connected to one side of the filter tank 2, and an installation shell 11 fixedly connected to the upper side of the filter tank 2, with an adjustment mechanism 12 provided inside the installation shell 11. The LNG output from the main body 1 of the subcooling unit first enters the filter tank 2. Multiple filter elements 5 fixed by two perforated plates 4 in the filter tank 2 filter impurities from the LNG, preventing impurities from flowing to the throttle valve 3 and causing blockage. The rotating shaft 6 can drive the mounting plate 7 and the cover plate 8 to rotate. The cover plate 8 can seal the upper end of a specific filter element 5. The U-shaped pipe 9 at the lower end of the rotating shaft 6 is used for sewage discharge. The adjustment mechanism 12 in the mounting shell 11 can adjust the state of the rotating shaft 6. This process initially filters impurities through the filter element 5, laying the foundation for the stable operation of the subsequent throttle valve 3. At the same time, the adjustment mechanism 12 provides control support for the switching of filter element 5 and sewage discharge, ensuring the continuous and effective operation of the filter tank 2.

[0018] In this embodiment, the output end of the subcooling device body 1 is connected to the input end of the filter tank 2 via a flange, and the output end of the filter tank 2 is connected to one end of the throttle valve 3 via a flange. The upper end of the rotating shaft 6 extends to the upper side of the filter tank 2. The upper end of the U-shaped connecting pipe 9 mates with the lower end of the filter element 5, and the U-shaped connecting pipe 9 is located directly below the cover plate 8. The lower end of the U-shaped connecting pipe 9 is connected to the upper end of the drain pipe 10 via a rotary joint, and one end of the drain pipe 10 extends to the outside of the filter tank 2. A drain valve 13 is installed at the outer end of the drain pipe 10. The main body 1 of the subcooling unit is connected to the filter tank 2, and the filter tank 2 is connected to the throttle valve 3 via flanges to ensure stable sealing during LNG transportation and reduce leakage. The upper end of the rotating shaft 6 extends to the upper side of the filter tank 2 for easy coordination with the regulating mechanism 12. When the filter element 5 needs to be cleaned, the upper end of the U-shaped pipe 9 mates with the lower end of the filter element 5. Since the U-shaped pipe 9 is directly below the cover plate 8, after the cover plate 8 seals the upper end of the filter element 5, impurities inside the filter element 5 can enter the drain pipe 10 through the U-shaped pipe 9 and the rotary joint. The impurities can be discharged by opening the drain valve 13. This process achieves targeted cleaning of impurities without the need for overall shutdown, ensuring continuous operation of the unit. The flange connection improves the reliability of the connection and reduces LNG transportation losses.

[0019] In this embodiment, the adjustment mechanism 12 includes a circular shell 121 fixedly connected to the upper end of the rotating shaft 6. A connecting column 122 is slidably fitted on the inner wall of the circular shell 121. A knob cover 123 is slidably fitted on the inner wall of the mounting shell 11. Locking blocks 124 are fixedly connected to both sides of the knob cover 123. The inner wall of the mounting shell 11 has multiple slots 125 corresponding to the positions of the filter element 5. A tension spring 126 is sleeved on the outer side of the connecting column 122. The locking blocks 124 engage with the slots 125, and the circular shell 121 is rotatably fitted on the inner wall of the mounting shell 11. The upper end of the connecting column 122 is fixedly connected to the lower side of the knob cover 123. The two ends of the tension spring 126 are fixedly connected to the knob cover 123 and the circular shell 121, respectively. Limiting grooves 14 are vertically formed on both sides of the inner wall of the circular shell 121. Limiting blocks 15 are fixedly connected to both sides of the connecting column 122, and the limiting blocks 15 are slidably fitted on the inner wall of the limiting grooves 14. In the adjustment mechanism 12, the circular shell 121 rotates with the rotating shaft 6. Pulling the knob cover 123 causes the connecting column 122 to slide along the inner wall of the circular shell 121, stretching the tension spring 126. The locking block 124 disengages from the locking groove 125. Rotating the knob cover 123 can drive the rotating shaft 6 to adjust the corresponding position of the cover plate 8. Releasing the knob cover 123 resets the tension spring 126, and the locking block 124 engages with the corresponding locking groove 125 to achieve positioning. The limiting block 15 slides along the vertical limiting groove 14 to ensure the stable sliding of the connecting column 122. This process precisely controls the rotation of the cover plate 8 and the U-shaped connecting pipe 9 through the adjustment mechanism 12 to switch between different filter elements 5. The limiting structure improves operational stability and ensures efficient filtration and cleaning.

[0020] When the device is in use, the LNG output from the main body 1 of the subcooling unit enters the filter tank 2 through a flange connection. Impurities are filtered through the filter element 5 between the perforated plates 4, preventing impurities from entering the throttle valve 3 connected through the flange. When the filter element 5 needs to be cleaned, the adjusting mechanism 12 inside the mounting housing 11 is operated, and the knob cover 123 is pulled to disengage the locking block 124 from the locking groove 125. Rotating the knob cover 123 drives the rotating shaft 6 to rotate via the connecting column 122 and the round shell 121. The limiting block 15 slides along the vertical limiting groove 14 to ensure stability. The cover plate 8 is moved to the top of the filter element 5 to be cleaned and its upper end is sealed. The U-shaped connector 9 is engaged with the lower end of the filter element 5. The drain valve 13 is opened, the internal pressure of the filter element 5 is reduced, and under the action of pressure difference, the filtered liquid is backflushed, so that the impurities in the filter element 5 enter the drain pipe 10 through the U-shaped connector 9 and the rotary joint and are discharged. After cleaning, the adjustment mechanism 12 is reset, the locking block 124 is locked into the locking groove 125 for positioning, and the device continues to filter LNG through the filter element 5 to ensure the stable operation of the throttle valve 3 and the subcooling device.

[0021] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. It is obvious to those skilled in the art that this utility model is not limited to the details of the above exemplary embodiments, and that it can be implemented in other specific forms without departing from the spirit or basic characteristics of this utility model.

[0022] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A subcooling device for LNG liquefaction, comprising a subcooling device body (1), characterized in that: The output end of the subcooling device body (1) is provided with a filter tank (2), and a throttle valve (3) is provided at one end of the filter tank (2). Two perforated plates (4) are installed on the inner wall of the filter tank (2). Multiple filter elements (5) are symmetrically installed between the two perforated plates (4). A rotating shaft (6) is rotatably fitted at the center of the two perforated plates (4). An mounting plate (7) is fixedly connected to the rotating shaft (6). A cover plate (8) that matches the upper end of the filter element (5) is fixedly connected to the lower side of both ends of the mounting plate (7). A U-shaped pipe (9) is fixedly connected to the lower end of the rotating shaft (6). A drain pipe (10) is fixedly connected to one side of the filter tank (2). An installation shell (11) is fixedly connected to the upper side of the filter tank (2). An adjustment mechanism (12) is provided inside the installation shell (11).

2. The LNG liquefaction subcooling device according to claim 1, characterized in that: The output end of the subcooling device body (1) is connected to the input end of the filter tank (2) through a flange. The output end of the filter tank (2) is connected to one end of the throttle valve (3) through a flange. The upper end of the rotating shaft (6) extends to the upper side of the filter tank (2).

3. The LNG liquefaction subcooling device according to claim 1, characterized in that: The upper end of the U-shaped connector (9) is matched with the lower end of the filter element (5), and the U-shaped connector (9) is located directly below the cover plate (8).

4. A subcooling device for LNG liquefaction according to claim 1, characterized in that: The lower end of the U-shaped connector (9) is connected to the upper end of the drain pipe (10) via a rotary joint. One end of the drain pipe (10) extends to the outside of the filter tank (2), and a drain valve (13) is installed at the outer end of the drain pipe (10).

5. A subcooling device for LNG liquefaction according to claim 1, characterized in that: The adjustment mechanism (12) includes a round shell (121) fixedly connected to the upper end of the rotating shaft (6). The inner wall of the round shell (121) is slidably fitted with a connecting column (122). The inner wall of the mounting shell (11) is slidably fitted with a knob cover (123). The two sides of the knob cover (123) are fixedly connected with locking blocks (124). The inner wall of the mounting shell (11) is provided with multiple locking grooves (125) corresponding to the position of the filter element (5). The outer side of the connecting column (122) is fitted with a tension spring (126).

6. A subcooling device for LNG liquefaction according to claim 5, characterized in that: The locking block (124) engages with the locking slot (125), the round shell (121) is rotatably fitted on the inner wall of the mounting shell (11), the upper end of the connecting column (122) is fixedly connected to the lower side of the knob cover (123), and the two ends of the tension spring (126) are fixedly connected to the knob cover (123) and the round shell (121) respectively.

7. A subcooling device for LNG liquefaction according to claim 5, characterized in that: Limiting grooves (14) are vertically opened on both sides of the inner wall of the circular shell (121), and limiting blocks (15) are fixedly connected to both sides of the connecting column (122). The limiting blocks (15) slide in fit on the inner wall of the limiting grooves (14).

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