An emergency treatment device and method for preventing leakage LNG from damaging a storage tank structure

Abstract

The application discloses an emergency treatment device and method for preventing leakage LNG from damaging the structure of a storage tank, comprising a grid module temperature difference avoidance system, a real-time leakage monitoring system for an LNG inner tank and a leakage LNG recovery system, wherein the leakage LNG recovery system recovers the low-temperature LNG leaking from the foam glass layer in time, prevents the low-temperature LNG from accumulating to cause a large internal and external temperature difference of the LNG outer tank, the temperature difference avoidance system distinguishes and numbers the LNG outer tank by using the grid module, performs cooling treatment on the grid module in the low-temperature area according to the low-temperature distribution caused by leakage, the real-time leakage monitoring system monitors the temperature change of the inner wall of the LNG outer tank in real time by using a diode temperature detector, determines the leakage area and the leakage temperature change condition in combination with the grid module number, and realizes real-time monitoring of the leakage of the LNG inner tank.

Description

Technical Field

[0001] This invention relates to the field of emergency response to LNG storage tank leaks, and more particularly to an emergency response device and method for preventing LNG leaks from damaging the tank structure. Background Technology

[0002] Currently, large LNG storage tanks are a crucial component of LNG receiving terminals, and their safety during LNG storage is of paramount importance. During LNG storage, various accidental loads can occur, and leaks, in particular, can cause the outer LNG tank to come into direct contact with the cryogenic LNG, resulting in varying cryogenic distributions. Since the leaked liquefied LNG is around -165°C, the resulting cryogenic distribution creates a significant temperature difference compared to the ambient temperature. Prolonged exposure to this large temperature difference can lead to cracking of the outer tank's concrete structure or further damage to the internal cryogenic reinforcing steel, ultimately affecting the tank's continued usability after emergency handling of the LNG leak. At present, leaks are primarily prevented through monitoring and early warning systems, lacking comprehensive emergency response systems and devices. Therefore, there is an urgent need to develop an emergency response device and method to prevent damage to the tank's concrete structure from leaking cryogenic LNG, further reducing tank rupture and damage from LNG leaks and maximizing emergency response time.

[0003] Firstly, existing Chinese patent publications for an LNG storage tank leak alarm system (CN202122434189.3) and a temperature monitoring and leak prevention device for LNG storage tanks (CN202022793587) both monitor and warn of LNG storage tank leaks, but lack emergency response systems and devices after an incident occurs. They cannot avoid the impact of the extreme temperature difference between the inside and outside of the LNG storage tank on the reinforced concrete tank structure after a leak. Existing devices all use ordinary concrete, which is significantly affected by extreme temperature differences. To reduce the impact of extreme temperature differences, high-strength, high-toughness, and high-freeze-thaw resistance reactive powder concrete (RPC) should be used to address the influence of temperature differences on the tank structure. Summary of the Invention

[0004] This invention discloses an emergency treatment device and method for preventing LNG leakage from damaging the structure of a storage tank. It can monitor whether the storage tank is leaking in real time and can recover the leaked LNG.

[0005] To address the aforementioned technical problems, this invention provides an emergency response device for preventing LNG leakage from damaging the storage tank structure, comprising a grid module temperature difference avoidance system, an LNG inner tank leakage real-time monitoring system, and a leaked LNG recovery system.

[0006] A grid module temperature difference avoidance system includes grid modules. Several grid modules are stacked into a cylindrical structure and fitted onto the outside of an LNG outer tank. Each grid module is connected to an input pipe. The input pipes in each row converge into a transport branch pipe. All the transport branch pipes converge into a transport main pipe. The transport main pipe is connected to a temporary storage tank.

[0007] A real-time monitoring system for LNG inner tank leakage, comprising temperature-sensing diodes, wherein each grid module is provided with one temperature-sensing diode at a corresponding position on the inner wall of the LNG outer tank;

[0008] A leaked LNG recovery system, comprising collection pipes evenly distributed at the bottom of the LNG outer tank, the collection pipes being connected to a guide pipe, and the guide pipe being connected to the temporary storage tank.

[0009] Furthermore, a cryogenic pump is installed on the guide pipe.

[0010] Furthermore, the input pipe is equipped with an electrically controllable valve.

[0011] Furthermore, the grid module is equipped with an emergency system shell.

[0012] An emergency response method is implemented through the following steps:

[0013] S1. Determine the low-temperature distribution area based on the temperature change at the leak point.

[0014] The temperature changes of the inner wall of the LNG outer tank are monitored in real time by temperature-sensing diodes to determine whether a leak has occurred in each grid module area.

[0015] When a leak occurs at a certain point, the temperature monitored by the temperature-sensing diodes in the grid module near the leak point will fluctuate to varying degrees. The low-temperature distribution area is determined based on the temperature fluctuation.

[0016] S2. Determine the grid module number for the low-temperature region.

[0017] The grid modules are labeled, and each grid module is assigned a number to identify the leak point. Then, the temperature fluctuation obtained in step S1 is compared and analyzed. The grid module with the largest temperature fluctuation is the area closest to the leak point.

[0018] The specific distribution of low-temperature regions is determined based on the magnitude of temperature fluctuations.

[0019] S3. Inject cryogenic LNG to avoid temperature differences in cryogenic distribution areas.

[0020] The input pipe connecting to the low-temperature region grid module is opened by controlling the electrically controllable valve on the input pipe;

[0021] The LNG in the temporary storage tank is transferred into the transport branch pipe through the main transport pipe to balance the excessive temperature difference between the inside and outside of the LNG outer tank.

[0022] S4. Monitor changes in the low-temperature distribution area and adjust the LNG injection location in real time.

[0023] Based on the real-time temperature changes monitored by the temperature-sensing diodes, the grid module area requiring LNG injection is continuously adjusted and expanded or reduced by repeating steps S1-S3.

[0024] The technical effects of this invention are as follows: 1. This invention designs a treatment device to prevent excessive internal and external temperature differences from damaging the outer tank structure of the storage tank due to low-temperature LNG leakage. By monitoring the temperature change of the inner wall of the LNG outer tank, the leakage point and leakage temperature are determined. Low-temperature LNG is used to cool the outer wall of the outer tank in the leakage area, thereby reducing the internal and external temperature difference of the LNG outer tank.

[0025] 2. The present invention is equipped with a leaked LNG recovery system, which promptly recovers the low-temperature LNG leaking from the foam glass layer, preventing the accumulation of low-temperature LNG from causing a large temperature difference between the inside and outside of the LNG tank, thus solving the problem of leaked LNG recovery.

[0026] 3. The present invention features a grid-modular temperature difference avoidance system. The grid modules are used to distinguish and number the LNG outer tanks. Based on the low temperature distribution caused by the leak, the grid modules in the low temperature area are cooled down, which solves the problem that conventional storage tanks cannot avoid the temperature difference between the inside and outside of the outer tank caused by the leak.

[0027] 4. The present invention is equipped with an LNG inner tank leakage real-time monitoring system, which monitors the temperature change of the inner wall of the LNG outer tank in real time through a diode thermometer, and determines the leakage area and leakage temperature change by combining the grid module number, thereby realizing real-time monitoring of LNG inner tank leakage. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of an emergency response device for preventing LNG leakage from damaging the structure of a storage tank, provided in an embodiment of the present invention.

[0029] Figure 2 A cross-sectional view of an emergency response device for preventing damage to a storage tank structure from leaked LNG, provided in an embodiment of the present invention.

[0030] Figure 3 This is a schematic diagram of the temperature difference avoidance system in an emergency response device for preventing damage to the storage tank structure caused by leaking LNG, provided in an embodiment of the present invention.

[0031] Figure 4This is a schematic diagram of the structure of a leaked LNG recovery system in an emergency response device for preventing damage to the storage tank structure from leaked LNG, provided in an embodiment of the present invention.

[0032] Figure 5 This is a schematic diagram of the arrangement of the collection pipe in an emergency treatment device for preventing damage to the storage tank structure from leaked LNG, provided in an embodiment of the present invention.

[0033] Reference numerals: 1. LNG outer tank; 2. Main transport pipe; 3. Grid module; 4. Branch transport pipe; 5. Electric controllable valve; 6. Tank foundation; 7. Temporary storage tank; 8. Emergency system casing; 9. Input pipe; 10. Temperature sensing diode; 11. Guide pipe; 12. Collection pipe; 13. Cryogenic pump. Detailed Implementation

[0034] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0035] This invention provides an emergency response device to prevent LNG leakage from damaging the structure of a storage tank, including a grid module temperature difference avoidance system, an LNG inner tank leakage real-time monitoring system, and a leaked LNG recovery system.

[0036] The grid module temperature difference avoidance system includes grid modules 3. The grid modules 3 are equipped with an emergency system shell 8. Several grid modules 3 are stacked into a cylindrical structure and installed on the outside of the LNG outer tank 1. Each grid module 3 is connected to an input pipe 9. Each row of input pipes 9 converges to the transport branch pipe 4. All transport branch pipes 4 converge to the transport main pipe 2. The transport main pipe 2 is connected to the temporary storage tank 7.

[0037] The LNG inner tank leakage real-time monitoring system includes temperature measuring diodes 10, and each grid module 3 has one temperature measuring diode 10 at the corresponding position on the inner wall of the LNG outer tank 1.

[0038] The leaked LNG recovery system includes a collection pipe 12 evenly distributed at the bottom of the LNG outer tank 1. The collection pipe 12 is connected to the guide pipe 11, and the guide pipe 11 is connected to the temporary storage tank 7.

[0039] The grid module temperature difference avoidance system divides the LNG outer tank 1 into 400×120 grid modules 3. These modules are separated by concrete slabs and operate independently. Each grid module 3 is connected to an input pipe 9, which connects to a transport main pipe 2 via a transport branch pipe 4. The transport main pipe 2 connects to a temporary storage tank 7, responsible for injecting cryogenic LNG into the grid module 3 area to balance the excessive temperature difference between the inside and outside of the LNG outer tank 1. An electrically controllable valve 5 is installed on the input pipe 9 to control the injection and shutdown of the grid module 3. A temperature-sensing diode 10 is installed inside the LNG outer tank 1 corresponding to each grid module 3 to monitor the temperature changes of the inner wall of that module's LNG outer tank 1 in real time. The LNG inner tank leakage real-time monitoring system determines whether a leak has occurred by monitoring the temperature changes of the inner wall of the outer tank. When the temperature monitored by the temperature-sensing diode 10 corresponding to a certain grid module 3 suddenly drops, it indicates that an LNG leak has occurred in that grid module 3 area. The outer LNG tank 1 is equipped with a leaked LNG recovery system at the bottom of the foam glass layer. Cryogenic LNG collection pipes 12 are evenly distributed at the bottom of the foam glass layer, and these pipes 12 are connected to a guide pipe 11, which in turn is connected to a temporary storage tank 7. This system is responsible for collecting the cryogenic LNG leaking from the inner tank to the bottom of the foam glass layer. A cryogenic pump 13 is installed on the guide pipe 11 to increase the collection speed of cryogenic LNG and reduce the amount of LNG vaporization.

[0040] The LNG outer tank 1, tank foundation 6, grid module 3, and concrete slab are all constructed using reactive powder concrete (RPC) to prevent irreparable damage or destruction to the concrete caused by low temperatures and excessive internal and external temperature differences.

[0041] according to Figure 1 , Figure 2 and Figure 4 As shown, the temperature difference avoidance system of grid module 3 divides the LNG outer tank 1 into 400×120 honeycomb grid modules 3. The grid modules 3 are separated by concrete slabs and are independent of each other. Each grid module 3 is connected to an input pipe 9. The input pipe 9 is connected to the main transport pipe 2 through the transport branch pipe 4. The main transport pipe 2 is connected to the temporary storage tank 7, which is responsible for injecting cryogenic LNG into the grid module 3 area to balance the excessive temperature difference between the inside and outside of the LNG outer tank 1. An electrically controllable valve 5 is installed in the input pipe 9 to control the injection and shutdown of the grid module 3.

[0042] according to Figure 1 and Figure 5As shown, the bottom of the foam glass of the LNG outer tank 1 is equipped with a leaked LNG recovery system, which is responsible for recovering LNG leaking from the inner tank into the foam glass layer, reducing the accumulation of leaked LNG in the foam glass layer and thus preventing a large temperature difference between the inside and outside of the LNG outer tank 1. Collection pipes 12 are evenly distributed at the bottom of the foam glass layer. The cryogenic LNG collection pipes 12 are connected to the guide pipes 11, which are connected to the temporary storage tank 7. These pipes are responsible for collecting the cryogenic LNG leaking from the inner tank into the bottom of the foam glass layer. A cryogenic pump 13 is installed on the guide pipes 11, which can improve the collection speed of cryogenic LNG and reduce the amount of LNG vaporization.

[0043] This invention also discloses an emergency treatment method for preventing damage to the concrete structure of a storage tank from leaked cryogenic LNG, the operation steps of which are as follows:

[0044] S1. Determine the low-temperature distribution area based on the temperature change at the leak point.

[0045] The temperature change of the inner wall of the LNG outer tank 1 is monitored in real time by temperature sensing diode 10 (diode model DT-670-SD diode), and the real-time temperature change is used to determine whether a leak has occurred in each grid module 3 area.

[0046] When a leak occurs at a certain point, the temperature monitored by the temperature-sensing diodes 10 in the grid module 3 near the leak point will fluctuate to varying degrees. The low-temperature distribution area is determined based on the temperature fluctuation.

[0047] S2. Determine the number of grid module 3 in the low-temperature region.

[0048] The LNG outer tank 1 was divided into 48,000 grid modules 3 using a 400×120 grid format. Then, each grid module 3 was labeled to determine a number to identify the leak point. The temperature fluctuation obtained in step S1 was then compared and analyzed. The grid module 3 with the largest temperature fluctuation was the area closest to the leak point.

[0049] The specific distribution of low-temperature regions is determined based on the magnitude of temperature fluctuations.

[0050] S3. Inject cryogenic LNG to avoid temperature differences in cryogenic distribution areas.

[0051] By controlling the electrically controllable valve 5 on the input pipe 9, the input pipe 9 connected to the low-temperature area grid module 3 is opened;

[0052] The LNG in the temporary storage tank 7 is fed into the transport branch pipe 4 through the transport main pipe 2 to balance the excessive temperature difference between the inside and outside of the LNG outer tank 1.

[0053] S4. Monitor changes in the low-temperature distribution area and adjust the LNG injection location in real time.

[0054] Based on the real-time temperature changes monitored by the temperature-sensing diode 10, the area of ​​the grid module 3 that needs to be injected with LNG is continuously adjusted and expanded or reduced by repeating steps S1-S3.

[0055] The above-described embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the claims.

Claims

1. An emergency response device for preventing damage to the structure of a storage tank from LNG leakage, characterized in that: This includes a grid module temperature difference avoidance system, an LNG inner tank leakage real-time monitoring system, and a leaked LNG recovery system; A grid module temperature difference avoidance system includes grid modules. Several grid modules are stacked into a cylindrical structure and fitted onto the outside of an LNG outer tank. Each grid module is connected to an input pipe. The input pipes in each row converge into a transport branch pipe. All the transport branch pipes converge into a transport main pipe. The transport main pipe is connected to a temporary storage tank. A real-time monitoring system for LNG inner tank leakage, comprising temperature-sensing diodes, wherein each grid module is provided with one temperature-sensing diode at a corresponding position on the inner wall of the LNG outer tank; A leaked LNG recovery system, comprising collection pipes evenly distributed at the bottom of the LNG outer tank, the collection pipes being connected to a guide pipe, and the guide pipe being connected to the temporary storage tank.

2. The emergency response device for preventing damage to the storage tank structure from leaked LNG according to claim 1, characterized in that: A cryogenic pump is installed on the guide pipe.

3. The emergency response device for preventing LNG leakage from damaging the tank structure according to claim 1, characterized in that: The input pipe is equipped with an electrically controllable valve.

4. The emergency response device for preventing LNG leakage from damaging the tank structure according to claim 1, characterized in that: The grid module is equipped with an emergency system shell.

5. An emergency response method using the emergency response device according to any one of claims 1-4, characterized by the following steps: S1. Determine the low-temperature distribution area based on the temperature change at the leak point. The temperature changes of the inner wall of the LNG outer tank are monitored in real time by temperature-sensing diodes to determine whether a leak has occurred in each grid module area. When a leak occurs at a certain point, the temperature monitored by the temperature-sensing diodes in the grid module near the leak point will fluctuate to varying degrees. The low-temperature distribution area is determined based on the temperature fluctuation. S2. Determine the grid module number for the low-temperature region. The grid modules are labeled, and each grid module is assigned a number to identify the leak point. Then, compare and analyze the temperature fluctuation obtained in step S1. The grid module with the largest temperature fluctuation is the area closest to the leak point. The specific distribution of low-temperature regions is determined based on the magnitude of temperature fluctuations. S3. Inject cryogenic LNG to avoid temperature differences in cryogenic distribution areas. The input pipe connecting to the low-temperature region grid module is opened by controlling the electrically controllable valve on the input pipe; The LNG in the temporary storage tank is transferred into the transport branch pipe through the main transport pipe to balance the excessive temperature difference between the inside and outside of the LNG outer tank. S4. Monitor changes in the low-temperature distribution area and adjust the LNG injection location in real time. Based on the real-time temperature changes monitored by the temperature-sensing diodes, the grid module area requiring LNG injection is continuously adjusted and expanded or reduced by repeating steps S1-S3.

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