A suction device for a tank loading and unloading tower and a tank

Abstract

The application discloses a kind of suction device of storage tank loading and unloading tower and storage tank, and suction device is located on the heat insulation module connected with the bottom wall of storage tank, and suction device includes loading and unloading tower support, support seat, main sink well mechanism, auxiliary cabin cleaning sink well mechanism, main unloading pipeline mechanism, auxiliary cabin cleaning pipeline mechanism and pigging pipeline mechanism;Pigging pipeline mechanism outlet end is communicated with the cavity in auxiliary cabin cleaning sink well mechanism, for injecting gaseous medium into auxiliary cabin cleaning sink well mechanism;The application is cooperated by the division of labour of main sink well mechanism and auxiliary cabin cleaning sink well mechanism, and gaseous medium is injected into auxiliary cabin cleaning sink well mechanism by pigging pipeline mechanism, gas-liquid synergistic displacement under low liquid level is realized, which helps to stabilize pump suction inlet pressure head, reduce residual liquid residual amount, improve cabin cleaning suction efficiency.

Description

Technical Field

[0001] This application relates to the field of liquefied gas storage and transportation equipment technology, and in particular to a suction device and storage tank for a tank loading and unloading tower. Background Technology

[0002] In the field of marine membrane-type liquefied gas (such as liquefied natural gas, LNG) storage and transportation, loading and unloading are typically achieved by installing a loading / unloading tower inside the storage tank, suspended from the upper wall and guided by support legs on the lower wall for horizontal movement. In related technologies, the unloading pump is usually located outside the tower or a single settling well is created on the bottom wall of the tank. Liquid is then pumped out or collected and discharged through the single settling well. This design can meet basic unloading requirements at normal liquid levels. However, when the tank is at a low liquid level or under turbulent conditions during ship navigation, the single settling well cannot consistently provide the pressure head required for the pump inlet. The main unloading pump is prone to cavitation and air suction, resulting in residual liquid at the bottom of the tank that is difficult to pump out. Summary of the Invention

[0003] In order to improve the defects of the main pump being prone to cavitation and suction during the low liquid level sweeping stage of the storage tank and the difficulty in pumping out the residual liquid, this application provides a suction device for the storage tank loading and unloading tower and the storage tank.

[0004] The suction device and storage tank of the storage tank loading and unloading tower provided in this application adopt the following technical solution:

[0005] A suction device and a storage tank for a tank loading / unloading tower are provided, mounted on an insulating module connected to the bottom wall of the storage tank. The device includes a loading / unloading tower support, a support base located at the bottom of the storage tank and movably connected to the bottom of the loading / unloading tower support, a main settling well mechanism connected to the support base, an auxiliary sweeping settling well mechanism, a main unloading pipeline mechanism connected to the loading / unloading tower support and communicating with the main settling well mechanism, an auxiliary sweeping pipeline mechanism communicating with the auxiliary sweeping settling well mechanism, and a cleaning pipeline mechanism extending vertically downward to the bottom of the loading / unloading tower support. The outlet end of the cleaning pipeline mechanism communicates with a cavity within the auxiliary sweeping settling well mechanism for injecting a gaseous medium into the auxiliary sweeping settling well mechanism.

[0006] By adopting the above technical solution, through the division of labor and cooperation between the main settling well mechanism and the auxiliary sweeping settling well mechanism, and by injecting gaseous medium into the auxiliary sweeping settling well mechanism in conjunction with the cleaning pipeline mechanism, gas-liquid synergistic displacement under low liquid level is achieved, which helps to stabilize the pump inlet head, reduce residual liquid, and improve the sweeping and pumping efficiency.

[0007] Preferably, the loading and unloading tower support includes a loading and unloading tower base located above the support base and movably connected to the support base, a main unloading support pipe, an auxiliary unloading support pipe, and a spare unloading support pipe connected to the loading and unloading tower base and arranged in an array along the periphery of the loading and unloading tower base, and transverse connecting rods that are connected to each of the main unloading support pipe, the auxiliary unloading support pipe, and the spare unloading support pipe in pairs; a plurality of transverse connecting rods are arranged in an array along the length direction of the main unloading support pipe.

[0008] By adopting the above technical solution, a rigid pipe rack structure is formed by the main unloading support pipe, auxiliary unloading support pipe, and spare unloading support pipe arranged in an array, as well as the horizontal connecting rods. This enhances the structural strength and stability of the bottom of the loading and unloading tower support, while also providing structural support for various pipelines.

[0009] Preferably, it also includes a limiting connector disposed on the insulation module and connected to the auxiliary sweeping settling well mechanism, the main settling well mechanism and the support seat respectively.

[0010] By adopting the above technical solution, the auxiliary sump cleaning and settling well mechanism, the main settling well mechanism and the support base are fixed by the limiting connector, which improves the connection between the settling well structure and the insulation module and helps to resist the structural stress caused by ship swaying.

[0011] Preferably, both the auxiliary sweeping and settling well mechanism and the main settling well mechanism are inserted into the insulation module; the auxiliary sweeping and settling well mechanism is provided with an auxiliary unloading cavity, and the main settling well mechanism is provided with a main unloading cavity.

[0012] By adopting the above technical solution, by inserting auxiliary sweeping and settling well mechanisms and main settling well mechanisms on the insulation module respectively, and by opening auxiliary unloading chambers and main unloading chambers inside, an independent suction and accommodating space for high and low liquid levels is constructed, reducing fluid interference between high-level high-flow unloading and low-level sweeping.

[0013] Preferably, the auxiliary cleaning pipeline mechanism includes an auxiliary suction pump inserted into the auxiliary unloading chamber, and an auxiliary suction pipe connected to the auxiliary suction pump and communicating with the auxiliary unloading support pipe.

[0014] By adopting the above technical solution, by configuring an auxiliary suction pump in the auxiliary unloading chamber and connecting it to the auxiliary unloading support pipe through the auxiliary suction pipe, an independent flow channel is formed specifically for low liquid level and residual liquid suction, thereby improving the residual liquid extraction efficiency.

[0015] Preferably, the pipeline cleaning mechanism includes a guide air hood fixedly connected to the loading / unloading tower base and with its open end inserted downward into the auxiliary unloading chamber, an air inlet pipe communicating with the guide air hood, and an air inlet drive assembly connected to the air inlet pipe; the guide air hood is sleeved on the outer wall of the auxiliary suction pump and the auxiliary suction pipe, the inner wall of the guide air hood and the outer wall of the auxiliary suction pipe surround to form a guide air chamber communicating with the auxiliary unloading chamber, the open end of the guide air hood maintains a gap with the bottom side wall of the auxiliary unloading chamber, and the outer wall of the guide air hood maintains a gap with the inner side wall of the auxiliary unloading chamber.

[0016] By adopting the above technical solution, a guide air chamber is formed outside the auxiliary suction pump and auxiliary suction pipe through the guide air hood, and the opening end of the guide air hood is kept at a gap with the bottom side wall of the auxiliary unloading chamber. The injected high-pressure gaseous medium forms a downward pushing air cushion in the guide air chamber, which pushes the residual liquid from the gap into the suction port of the auxiliary suction pump, forming a synergistic displacement mechanism of air pressure pushing down and bottom suction, which accelerates the discharge of residual liquid.

[0017] Preferably, the main unloading pipeline mechanism includes a main unloading pump inserted into the main unloading chamber, a main suction pipe connected to the main unloading pump and communicating with the main unloading support pipe and fixedly connected to the loading and unloading tower base, and a main unloading base connected to the outer wall of the main suction pipe and fixedly connected to the loading and unloading tower base.

[0018] By adopting the above technical solution, the main unloading pump and the main suction pipe work together to achieve large liquid level and large flow rate main unloading operation. The fixed connection between the main unloading base and the loading and unloading tower base ensures the structural stability of the main unloading pipeline mechanism during operation.

[0019] Preferably, the spare unloading support pipe includes a spare support pipe body and a spare unloading pump inserted into the bottom opening of the spare support pipe body.

[0020] By adopting the above technical solution, the backup support pipe body, together with the backup unloading pump at the bottom, provides redundant unloading capacity. It can be replaced in time when the main unloading pump or auxiliary suction pump fails, thus ensuring the operational reliability of the loading and unloading system.

[0021] Preferably, it also includes a loading pipe connected to the outer wall of the spare unloading support pipe and arranged in a vertical direction.

[0022] By adopting the above technical solution, the loading pipeline is a cargo loading channel for injecting liquefied gas medium into the storage tank. When cargo loading is performed, the liquefied gas medium is transported from the top of the loading tower to the bottom of the tower via the loading pipeline and injected into the bottom of the storage tank.

[0023] A storage tank, including the suction device of the aforementioned storage tank loading and unloading tower.

[0024] By adopting the above technical solution, the storage tank including the suction device can improve the residual liquid drying rate and tank cleaning efficiency during the storage and transportation of liquefied gas, thus ensuring the long-term safe operation of the storage tank.

[0025] In summary, this application includes at least one of the following beneficial technical effects:

[0026] 1. By coordinating the main settling well mechanism and the auxiliary sweeping settling well mechanism, and by injecting gaseous medium into the auxiliary sweeping settling well mechanism in conjunction with the cleaning pipeline mechanism, gas-liquid synergistic displacement under low liquid level is achieved, which helps to stabilize the pump inlet head, reduce residual liquid, and improve the sweeping pumping efficiency.

[0027] 2. A guide air chamber is formed outside the auxiliary suction pump and auxiliary suction pipe by a guide air hood, and the opening end of the guide air hood is kept at a gap with the bottom side wall of the auxiliary unloading chamber. The injected high-pressure gaseous medium forms a downward pushing air cushion in the guide air chamber, forming a synergistic displacement mechanism of downward air pressure and bottom suction, which accelerates the discharge and vaporization of residual liquid. Attached Figure Description

[0028] Figure 1 This is a cross-sectional view of an embodiment of this application. Figure 1 .

[0029] Figure 2 This is a three-dimensional structural diagram of an embodiment of this application.

[0030] Figure 3 This is a cross-sectional view of an embodiment of this application. Figure 2 .

[0031] Explanation of reference numerals in the attached figures:

[0032] 1. Insulation module; 2. Loading / unloading tower support; 21. Loading / unloading tower base; 211. Insertion slot; 22. Main unloading support pipe; 23. Auxiliary unloading support pipe; 24. Spare unloading support pipe; 241. Spare support pipe body; 242. Spare unloading pump; 243. Loading pipeline; 25. Horizontal connecting rod; 3. Support seat; 31. Insertion flange; 4. Main settling well mechanism; 41. Main unloading chamber; 5. Auxiliary sweeping settling well mechanism; 51. Auxiliary unloading chamber; 6. Main unloading pipeline mechanism; 61. Main unloading pump; 62. Main suction pipe; 63. Main unloading base; 7. Auxiliary sweeping pipeline mechanism; 71. Auxiliary suction pump; 72. Auxiliary suction pipe; 8. Pipeline cleaning mechanism; 81. Guide air hood; 811. Air guide chamber; 82. Air inlet pipe; 83. Air inlet drive assembly; 9. Limiting connector. Detailed Implementation

[0033] The following is in conjunction with the appendix Figures 1 to 3 This application will be described in further detail.

[0034] This application discloses a suction device for a tank loading / unloading tower and a storage tank. (Refer to...) Figure 1 A suction device for a tank loading and unloading tower is mounted on an insulating module 1 connected to the bottom wall of the tank. It includes a loading and unloading tower support 2, a support base 3 located at the bottom of the tank and movably connected to the bottom of the loading and unloading tower support 2, a main settling well mechanism 4 connected to the support base 3, an auxiliary sweeping settling well mechanism 5, a main unloading pipeline mechanism 6 connected to the loading and unloading tower support 2 and communicating with the main settling well mechanism 4, an auxiliary sweeping pipeline mechanism 7 communicating with the auxiliary sweeping settling well mechanism 5, and a cleaning pipeline mechanism 8 extending vertically downward to the bottom of the loading and unloading tower support 2. The outlet end of the cleaning pipeline mechanism 8 is connected to the cavity inside the auxiliary sweeping settling well mechanism 5 for injecting gaseous medium into the auxiliary sweeping settling well mechanism 5.

[0035] In this application, the storage tank is filled with liquefied natural gas or other liquefied gaseous media. During the normal high-level or high-flow unloading phase, the main unloading pipeline mechanism 6 and the main settling well mechanism 4 work together to extract a large flow of liquid from the storage tank. When the liquid level in the storage tank drops to the low-level tank cleaning phase, the main unloading pipeline mechanism 6 stops extracting and the auxiliary tank cleaning pipeline mechanism 7 is opened. The residual liquid at the bottom of the tank collects in the auxiliary tank cleaning settling well mechanism 5. At the same time, high-pressure nitrogen or gaseous liquefied natural gas or other gaseous media are injected into the auxiliary tank cleaning settling well mechanism 5 through the cleaning pipeline mechanism 8. The gaseous media forms a downward pressure cushion in the auxiliary tank cleaning settling well mechanism 5, which exerts a downward force on the residual liquid. The mechanical pressure, in conjunction with the suction action of the auxiliary tank cleaning pipeline mechanism 7, forces the residual liquid into the suction port for discharge. This application achieves high and low liquid level separation suction through the modular design of the main settling well mechanism 4 and the auxiliary tank cleaning settling well mechanism 5, combined with the gas-liquid synergistic displacement method of the cleaning pipeline mechanism 8. This reduces the risk of pump cavitation and air suction during low liquid level tank cleaning, reduces the residual liquid at the bottom of the tank, and improves the efficiency of residual liquid extraction and tank cleaning and drainage. The movable plug-in connection between the support base 3 and the bottom of the loading and unloading tower support 2 can adapt to the translation and thermal contraction changes of the bottom of the storage tank, reduce local stress concentration, and improve the operational stability and safety of the storage tank system.

[0036] Furthermore, such as Figure 2 and Figure 3 As shown, the loading and unloading tower support 2 of this application includes a loading and unloading tower base 21 located above the support base 3 and movably connected to the support base 3, a main unloading support pipe 22, an auxiliary unloading support pipe 23, and a spare unloading support pipe 24 connected to the loading and unloading tower base 21 and arranged in an array along the periphery of the loading and unloading tower base 21, and transverse connecting rods 25 that are connected in pairs to the main unloading support pipe 22, the auxiliary unloading support pipe 23, and the spare unloading support pipe 24 respectively; the multiple transverse connecting rods 25 are arranged in an array along the length direction of the main unloading support pipe 22.

[0037] The loading and unloading tower base 21 has an insertion groove 211 at its bottom, and the support base 3 has an insertion protrusion 31 that can be inserted into the insertion groove 211, forming an axial guide and horizontal translation fit; the main unloading support pipe 22, the auxiliary unloading support pipe 23, and the spare unloading support pipe 24 are all vertical tubular structures, with their bottom ends fixedly installed on the loading and unloading tower base 21, and are evenly distributed circumferentially to form a three-dimensional truss column. The transverse connecting rod 25 is transversely straddled between two adjacent support pipes and fixedly connected, and is arranged in a multi-segment array in the vertical direction, thereby ensuring the loading and unloading... The bottom of the unloading tower support 2 forms a rigid pipe frame structure. This application integrates the main unloading support pipe 22, auxiliary unloading support pipe 23, spare unloading support pipe 24 and transverse connecting rod 25 into an integrated truss layout, which enhances the structural rigidity and bending and shear resistance of the bottom of the unloading tower support 2. It can withstand the fluid impact load under ship navigation or swaying conditions. At the same time, the main unloading support pipe 22, auxiliary unloading support pipe 23 and spare unloading support pipe 24 have the dual functions of structural support and fluid transportation channel, which improves space utilization and overall stability.

[0038] Furthermore, such as Figure 1 As shown, this application also includes a limiting connector 9 disposed on the insulation module 1 and connected to the auxiliary sweeping settling well mechanism 5, the main settling well mechanism 4 and the support base 3 respectively; the limiting connector 9 is fixedly installed on the pre-embedded structure of the insulation module 1 at the bottom wall of the storage tank, and multiple connecting arms extend from the periphery of the limiting connector 9, which are fixedly connected to the outer wall of the auxiliary sweeping settling well mechanism 5, the outer wall of the main settling well mechanism 4 and the outer wall of the support base 3 respectively; this application uses the limiting connector 9 to constrain and fix the auxiliary sweeping settling well mechanism 5, the main settling well mechanism 4 and the support base 3 to the insulation module 1 at multiple points, and uses mechanical limiting to prevent the settling well mechanism from relative displacement and loosening when the ship is rocking or liquid is scouring, thereby reducing the local stress concentration of the settling well mechanism on the corrugated sealing membrane of the bottom wall of the storage tank, extending the service life of the sealing membrane, and ensuring the docking accuracy and structural reliability of the bottom suction structure.

[0039] Specifically, such as Figure 1As shown, the auxiliary sweeping settling well mechanism 5 and the main settling well mechanism 4 of this application are both inserted into the insulation module 1; the auxiliary sweeping settling well mechanism 5 is provided with an auxiliary unloading cavity 51, and the main settling well mechanism 4 is provided with a main unloading cavity 41. The main settling well mechanism 4 and the auxiliary sweeping settling well mechanism 5 are deeply embedded inside the insulation module 1. The main unloading cavity 41 and the auxiliary unloading cavity 51 are both deep well-shaped cavities with top openings, and the cross-sectional area and depth of the main unloading cavity 41 are smaller than those of the auxiliary unloading cavity 51; the main settling well mechanism 4 and the auxiliary sweeping settling well mechanism 5 are arranged asymmetrically to avoid each other below the loading and unloading tower base 21; by setting independent main unloading cavities 41 and auxiliary unloading cavities 51 on the insulation module 1, this application constructs a high and low liquid level separation suction space. The auxiliary unloading cavity 51 is placed deep in the low position to concentrate and collect low liquid level residual liquid, reducing fluid interference during the high and low liquid level suction process and reducing the probability of centrifugal pump cavitation.

[0040] More specifically, such as Figure 1 As shown, the auxiliary cleaning pipeline mechanism 7 of this application includes an auxiliary suction pump 71 inserted in the auxiliary unloading chamber 51, and an auxiliary suction pipe 72 connected to the auxiliary suction pump 71 and communicating with the auxiliary unloading support pipe 23. An auxiliary suction pump 71 is placed at the bottom of the auxiliary unloading chamber 51. An auxiliary suction pipe 72 extends vertically upward, with one end sealed and connected to the outlet end of the auxiliary suction pump 71, and the other end passing through the auxiliary unloading chamber 51 and sealed and connected to the inner cavity of the auxiliary unloading support pipe 23 located above. During the tank sweeping operation, the auxiliary suction pump 71 is started, and the residual liquid in the auxiliary unloading chamber 51 is sucked into the auxiliary suction pump 71, transported through the auxiliary suction pipe 72 to the auxiliary unloading support pipe 23, and then discharged out of the storage tank. This application shortens the extraction path of the sweeping medium and improves the pumping rate of residual liquid at low liquid levels by placing the auxiliary suction pump 71 deep at the bottom of the auxiliary unloading chamber 51 and utilizing the deep accumulation of liquid column pressure head in the auxiliary unloading chamber 51, in conjunction with the straight flow channel of the auxiliary suction pipe 72 and the auxiliary unloading support pipe 23.

[0041] In addition, such as Figure 1As shown, the pipeline cleaning mechanism 8 of this application includes a guide air hood 81 fixedly connected to the loading and unloading tower base 21 and inserted downward into the auxiliary unloading chamber 51, an air inlet pipe 82 communicating with the guide air hood 81, and an air inlet drive assembly 83 connected to the air inlet pipe 82; the guide air hood 81 is sleeved on the outer wall of the auxiliary suction pump 71 and the auxiliary suction pipe 72, and the inner wall of the guide air hood 81 and the outer wall of the auxiliary suction pipe 72 surround to form a guide air chamber 811 communicating with the auxiliary unloading chamber 51, the open end of the guide air hood 81 maintains a gap with the bottom side wall of the auxiliary unloading chamber 51, and the outer wall of the guide air hood 81 maintains a gap with the inner wall of the auxiliary unloading chamber 51. The guide gas hood 81 has an inverted cylindrical structure with a closed top and an open bottom. The top of the guide gas hood 81 is fixedly connected to the loading and unloading tower base 21. The air inlet pipe 82 is sealed and connected to the air guide cavity 811 at the top of the guide gas hood 81. The air inlet drive assembly 83 is located outside the tank or at the top of the tower and is connected to the inlet of the air inlet pipe 82. The lower open end of the guide gas hood 81 extends into the auxiliary unloading cavity 51 and is suspended above the bottom side wall of the auxiliary unloading cavity 51, forming a bottom liquid inlet gap. An annular flow channel gap is formed between the outer wall of the guide gas hood 81 and the inner wall of the auxiliary unloading cavity 51 for the residual liquid at the bottom of the tank to flow in.

[0042] During the tank cleaning operation, the air intake drive assembly 83 drives the high-pressure gaseous medium to be injected into the upper part of the air guide chamber 811 through the air intake pipe 82. Due to the physical sealing effect of the top of the air guide shroud 81, the high-pressure gaseous medium cannot escape upwards and accumulates above the liquid surface in the air guide chamber 811, forming a high-pressure air cushion that pushes downwards. The high-pressure air cushion applies static pressure to the liquid surface, forcing the residual liquid inside the air guide shroud 81 to be forcibly displaced downwards through the bottom liquid inlet gap to the suction port of the auxiliary suction pump 71. This application constructs a gas-liquid synergistic displacement mechanism of top air pressure pushing downwards and bottom pump suction through the closed air guide chamber 811 formed by the air guide shroud 81 and the double gap structure. This provides an additional pressure head for the suction port of the auxiliary suction pump 71, prevents gaseous medium leakage and liquid reverse pushing, eliminates pump cavitation and suction phenomena at low liquid levels, accelerates the vaporization and discharge of residual liquid, and shortens the tank cleaning cycle.

[0043] This application also discloses that a one-way inlet valve or a check seal structure (not shown in the figure) is provided at the liquid inlet gap between the lower opening end of the flow guide hood 81 and the bottom side wall of the auxiliary unloading chamber 51.

[0044] During the tank cleaning and suction operation, when the unguided air chamber 811 is not filled with air, the one-way liquid inlet valve plate is opened under the hydraulic or gravity action of the residual liquid in the storage tank, allowing the residual liquid at the bottom of the storage tank to flow into the auxiliary unloading chamber 51 and the interior of the guide air cover 81.

[0045] When the intake drive assembly 83 is activated to supply air to the intake pipe 82, the intake drive assembly 83 is configured to adopt an intermittent pulse inflation mode, that is, the intake drive assembly 83 is controlled to inject a preset amount of gaseous medium into the intake pipe 82 within a preset time and then suspend inflation, while the auxiliary suction pump 71 continuously performs the suction action.

[0046] During this process, the gaseous medium enters the upper cavity of the gas guiding chamber 811, causing a micro-positive pressure within a preset range to be formed inside the gas guiding chamber 811 above the residual liquid surface, rather than generating violent pressure difference fluctuations.

[0047] The slight positive pressure in the air guide chamber 811 acts in the opposite direction on the one-way liquid inlet valve plate, causing the one-way liquid inlet valve plate to automatically adhere and seal the liquid inlet gap, preventing the high-pressure gaseous medium in the air guide chamber 811 from leaking to the outside of the auxiliary unloading chamber 51 and the main space of the storage tank.

[0048] This application uses a one-way inlet valve to block the leakage channel of gaseous medium; maintains the pressure in the air guide chamber 811 at a slightly positive pressure; and, combined with an intermittent pulsed air supply rhythm, ensures a stable pressure head is provided to the suction port of the auxiliary suction pump 71 while reducing the consumption of gaseous medium and minimizing the interference of violent fluid fluctuations on the pump's suction process, thus helping to improve the continuity of low-level tank sweeping operations and the residual liquid extraction effect.

[0049] And, as Figure 1 As shown, the main unloading pipeline mechanism 6 of this application includes a main unloading pump 61 inserted in the main unloading chamber 41, a main suction pipe 62 connected to the main unloading pump 61 and communicating with the main unloading support pipe 22 and fixedly connected to the loading and unloading tower base 21, and a main unloading base 63 connected to the outer wall of the main suction pipe 62 and fixedly connected to the loading and unloading tower base 21. The main unloading pump 61, as a high-flow centrifugal pump, is placed at the bottom of the main unloading chamber 41. The main suction pipe 62 extends vertically upward, with its lower end sealed and connected to the outlet of the main unloading pump 61, and its upper end passing through the loading and unloading tower base 21 and sealed and connected to the inner cavity of the main unloading support pipe 22. The main unloading base 63 is sleeved on the outside of the main suction pipe 62 and fixedly connected to the loading and unloading tower base 21, providing longitudinal and radial rigid support for the main suction pipe 62 and the main unloading pump 61. During high-level unloading, the main unloading pump 61 starts, and the high-flow liquid in the main unloading chamber 41 is quickly transported to the outside of the tank through the main suction pipe 62 and the main unloading support pipe 22. This application uses the main unloading base 63 to fix the main suction pipe 62 to the loading and unloading tower base 21, which enhances the structural rigidity of the main unloading pipeline, reduces pipeline vibration caused by high-flow scouring, and ensures the smoothness and stability of the main unloading process.

[0050] Furthermore, such as Figure 3As shown, the backup unloading support pipe 24 of this application includes a backup support pipe body 241 and a backup unloading pump 242 inserted into the bottom opening of the backup support pipe body 241. The backup support pipe body 241 is fixed on the loading and unloading tower base 21, and the backup unloading pump 242 is installed at the bottom opening of the backup support pipe body 241 and placed above the bottom wall of the storage tank. When the main unloading pump 61 or the auxiliary suction pump 71 fails or needs to be shut down for maintenance, the backup unloading pump 242 is started, and the liquid is drawn by the backup unloading pump 242 and discharged upward along the backup support pipe body 241. By setting up the backup support pipe body 241 and the backup unloading pump 242, this application improves the emergency response capability and operational reliability of the loading and unloading tower system.

[0051] Furthermore, such as Figure 2 As shown, this application also includes a loading pipe 243 connected to the outer wall of the backup unloading support pipe 24 and arranged vertically. The loading pipe 243 has a vertically elongated tubular structure and is attached parallel to the outer peripheral side wall of the backup unloading support pipe 24. The lower end of the loading pipe 243 extends to the bottom area of ​​the storage tank, and the upper end of the loading pipe 243 extends upward to the top of the loading and unloading tower and connects to an external medium transmission pipeline. The loading pipe 243 and the outer wall of the backup unloading support pipe 24 are fixedly connected at multiple points by fixed connectors (such as clamps, cable clamps, or welded support frames), so that the loading pipe 243 and the backup unloading support pipe 24 form an integrated vertical structure.

[0052] Loading pipe 243 is a cargo loading channel for injecting liquefied gas medium into the storage tank. When cargo loading is performed, the liquefied gas medium is transported from the top of the loading tower to the bottom of the tower and injected into the bottom of the storage tank via loading pipe 243.

[0053] Specifically, this application also discloses a storage tank, including a tank bottom wall, a support base 3 fixed to the tank bottom wall, a loading and unloading tower suspended from the upper wall of the tank, and a suction device for the loading and unloading tower; the loading and unloading tower base 21 at the bottom of the loading and unloading tower is guided to move horizontally by the support base 3. The tank bottom wall is covered with an insulation barrier composed of a corrugated sealing membrane and an insulation module 1. The support base 3 is fixed to the insulation module 1. The loading and unloading tower is suspended from the upper wall of the tank. The loading and unloading tower base 21 at the bottom of the loading and unloading tower is inserted into the support base 3, and its horizontal translation stroke is limited by the support base 3 to adapt to the thermal expansion and contraction of the storage tank during the cold or hot tank process.

[0054] The implementation principle of the suction device of the storage tank loading and unloading tower in this application embodiment is as follows:

[0055] During use, in the main unloading stage, the tank is in a high liquid level condition. The main unloading pump 61 in the main unloading chamber 41 is started. The main unloading pump 61 draws a large flow of liquefied gas medium from the main unloading chamber 41. The medium is quickly transported to the outside of the tank through the main suction pipe 62 and the main unloading support pipe 22.

[0056] When the liquid level in the storage tank drops to the preset tank cleaning level, the main unloading pump 61 stops running and the auxiliary suction pump 71 in the auxiliary unloading chamber 51 is started. The residual liquid at the bottom of the tank flows into the auxiliary unloading chamber 51 along the surface of the insulation module 1 and enters the interior of the guide air cover 81 through the flow channel gap on the outside of the guide air cover 81 and the liquid inlet gap at the bottom.

[0057] The intake drive assembly 83 is activated synchronously, and high-pressure nitrogen is injected into the upper part of the air guide chamber 811 inside the air guide shroud 81 through the intake pipe 82. The high-pressure nitrogen forms a downward high-pressure air cushion in the closed air guide chamber 811, which applies downward static pressure to the residual liquid surface in the air guide shroud 81, forming a top pressure displacement effect. Under the combined action of the downward pressure of the air cushion and the suction at the bottom of the auxiliary suction pump 71, the residual liquid is forced into the suction port of the auxiliary suction pump 71 and is drawn out of the tank through the auxiliary suction pipe 72 and the auxiliary unloading support pipe 23. This achieves complete drainage of gas and liquid at low liquid levels, stabilizes the pump suction head, and reduces the risk of cavitation and air suction.

[0058] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A suction device for a tank loading / unloading tower, mounted on an insulating module (1) connected to the bottom wall of the tank, characterized in that, The system includes a loading and unloading tower support (2), a support base (3) located at the bottom of the storage tank and movably connected to the bottom of the loading and unloading tower support (2), a main settling well mechanism (4) connected to the support base (3), an auxiliary sweeping settling well mechanism (5), a main unloading pipeline mechanism (6) connected to the loading and unloading tower support (2) and communicating with the main settling well mechanism (4), an auxiliary sweeping pipeline mechanism (7) communicating with the auxiliary sweeping settling well mechanism (5), and a cleaning pipeline mechanism (8) extending vertically downward to the bottom of the loading and unloading tower support (2); the outlet end of the cleaning pipeline mechanism (8) is connected to the cavity inside the auxiliary sweeping settling well mechanism (5) for injecting gaseous medium into the auxiliary sweeping settling well mechanism (5); The loading and unloading tower support (2) includes a loading and unloading tower base (21) located above the support base (3) and movably connected to the support base (3), a main unloading support pipe (22) connected to the loading and unloading tower base (21) and arranged in an array along the periphery of the loading and unloading tower base (21), an auxiliary unloading support pipe (23), and a spare unloading support pipe (24); the auxiliary hull sweeping settling well mechanism (5) is provided with an auxiliary unloading cavity (51), and the main settling well mechanism (4) is provided with a main unloading cavity (41); the auxiliary hull sweeping pipeline mechanism (7) includes an auxiliary suction pump (71) inserted into the auxiliary unloading cavity (51), and an auxiliary suction pipe (72) connected to the auxiliary suction pump (71) and communicating with the auxiliary unloading support pipe (23); The pipeline cleaning mechanism (8) includes a guide air hood (81) fixedly connected to the loading and unloading tower base (21) and with its open end inserted downward into the auxiliary unloading chamber (51), an air inlet pipe (82) communicating with the guide air hood (81), and an air inlet drive assembly (83) connected to the air inlet pipe (82). The guide air hood (81) is sleeved on the outer wall of the auxiliary suction pump (71) and the auxiliary suction pipe (72). The inner wall of the guide air hood (81) and the outer wall of the auxiliary suction pipe (72) surround each other to form a guide air chamber (811) communicating with the auxiliary unloading chamber (51). The open end of the guide air hood (81) maintains a gap with the bottom side wall of the auxiliary unloading chamber (51), and the outer wall of the guide air hood (81) maintains a gap with the inner wall of the auxiliary unloading chamber (51).

2. The suction device for a tank loading / unloading tower according to claim 1, characterized in that, The loading and unloading tower support (2) includes transverse connecting rods (25) that are connected in pairs to the main unloading support pipe (22), the auxiliary unloading support pipe (23) and the spare unloading support pipe (24); a plurality of transverse connecting rods (25) are arranged in an array along the length direction of the main unloading support pipe (22).

3. The suction device for a tank loading / unloading tower according to claim 1, characterized in that, It also includes a limiting connector (9) disposed on the insulation module (1) and connected to the auxiliary sweeping settling well mechanism (5), the main settling well mechanism (4) and the support base (3) respectively.

4. The suction device for a tank loading / unloading tower according to claim 2, characterized in that, The auxiliary sweeping and settling well mechanism (5) and the main settling well mechanism (4) are both inserted into the insulation module (1).

5. The suction device for a tank loading / unloading tower according to claim 4, characterized in that, The main unloading pipeline mechanism (6) includes a main unloading pump (61) inserted in the main unloading chamber (41), a main suction pipe (62) connected to the main unloading pump (61) and communicating with the main unloading support pipe (22) and fixedly connected to the loading and unloading tower base (21), and a main unloading base (63) connected to the outer wall of the main suction pipe (62) and fixedly connected to the loading and unloading tower base (21).

6. The suction device for a tank loading / unloading tower according to claim 2, characterized in that, The backup unloading support pipe (24) includes a backup support pipe body (241) and a backup unloading pump (242) inserted into the bottom opening of the backup support pipe body (241).

7. The suction device for a tank loading / unloading tower according to claim 2, characterized in that, It also includes a loading pipe (243) that is connected to the outer wall of the spare unloading support pipe (24) and is arranged in a vertical direction.

8. A storage tank, characterized in that, The suction device includes the tank loading and unloading tower according to any one of claims 1 to 7.

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