BOG pipeline splash-proof structure in large marine LNG storage tanks

Abstract

This utility model discloses a splash-proof structure for the BOG pipeline in a large marine LNG storage tank, comprising: a BOG pipeline; a protective cover located in the storage tank and welded and fixed to the outer wall of the BOG pipeline inlet; the protective cover and the BOG pipeline are arranged coaxially; the opening of the protective cover faces downward and is lower than the BOG pipeline inlet; a splash-proof bucket is arranged coaxially below the BOG pipeline inlet, with its larger opening facing upward and its smaller opening facing downward; the diameter of the larger opening of the splash-proof bucket is larger than the diameter of the BOG pipeline inlet; the splash-proof bucket is fixed to the protective cover by a connecting rod on each side; the splash-proof bucket prevents a large amount of LNG from splashing into the BOG pipeline from the storage tank; and the LNG flowing into the splash-proof bucket can exit through the smaller opening at the bottom of the splash-proof bucket. The BOG pipeline splash-proof structure can block violently fluctuating LNG through the splash-proof bucket, making it less likely for LNG to splash into the BOG pipeline; the protective cover prevents LNG from flowing into the splash-proof bucket; and LNG entering the splash-proof bucket can be discharged in time and is less likely to enter the BOG pipeline through the splash-proof bucket.

Description

Technical Field

[0001] This utility model relates to the field of LNG storage tanks, specifically to a splash-proof structure for BOG pipelines in large marine LNG storage tanks. Background Technology

[0002] LNG storage tanks are used to store LNG (liquefied natural gas). When heated, LNG evaporates to form BOG (bottled natural gas). The BOG gas in the LNG storage tank is discharged through BOG pipelines, which are usually located at the top of the tank and connected to the gas inlet of the tank. Large marine LNG storage tanks are installed on ships. The BOG gas in these tanks is transported to compressors or boilers through BOG pipelines. During navigation, the ship will pitch and roll due to the waves. LNG in the storage tank is very likely to splash into the BOG pipeline due to the pitching and rolling, which will greatly affect the discharge of BOG. ​​Furthermore, the LNG splashed into the BOG pipeline is very likely to evaporate due to heat leakage from the BOG pipeline. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a splash-proof structure for BOG pipelines in large marine LNG storage tanks.

[0004] To solve the above problems, the technical solution adopted by this utility model is: a BOG pipeline anti-splashing structure in a large marine LNG storage tank, comprising: a BOG pipeline, characterized in that: it further comprises: a protective cover located in the storage tank and welded and fixed to the outer wall of the BOG pipeline inlet, the protective cover and the BOG pipeline are arranged coaxially, the opening of the protective cover faces downward and is lower than the BOG pipeline inlet, and an anti-splash bucket coaxially arranged below the BOG pipeline inlet is provided, the large opening of the anti-splash bucket faces upward and the small opening faces downward, the diameter of the large opening of the anti-splash bucket is larger than the diameter of the BOG pipeline inlet, and the front, back, left and right sides of the anti-splash bucket are fixed to the protective cover by a connecting rod, the anti-splash bucket can prevent a large amount of LNG in the storage tank from splashing into the BOG pipeline, and the LNG flowing into the anti-splash bucket can leave through the small opening at the bottom of the anti-splash bucket.

[0005] Furthermore, in the aforementioned large marine LNG storage tank, the BOG pipeline splash-proof structure includes a circular shield and a circular splash-proof hopper.

[0006] Furthermore, in the aforementioned large marine LNG storage tank, the BOG pipeline splash-proof structure has a gap height of 30-50cm between the top of the splash-proof hopper and the bottom of the BOG pipeline.

[0007] Furthermore, in the aforementioned large marine LNG storage tank, the BOG pipeline splash-proof structure has the following feature: the diameter of the large opening at the top of the splash-proof hopper is 2 to 3 times the inner diameter of the BOG pipeline.

[0008] Furthermore, in the aforementioned large marine LNG storage tank, the BOG pipeline splash-proof structure has a distance of at least 30cm between the BOG pipeline inlet and the inner wall of the top of the shield.

[0009] Furthermore, in the aforementioned large marine LNG storage tank, the BOG pipeline splash-proof structure has a splash-proof hopper with a taper of 10 to 20 degrees.

[0010] Furthermore, in the aforementioned large marine LNG storage tank, the BOG pipeline splash-proof structure has the following feature: the diameter of the bottom opening of the shield is 200-260 cm larger than the outer diameter of the splash-proof hopper.

[0011] Furthermore, in the aforementioned large marine LNG storage tank, the BOG pipeline splash-proof structure has a bottom opening diameter of 10-20 cm.

[0012] The advantages of this utility model are: the BOG pipeline anti-splash structure can block the violently fluctuating LNG through the anti-splash bucket, making it difficult for LNG to splash into the BOG pipeline; the protective cover can prevent LNG from flowing into the anti-splash bucket; and the LNG that enters the anti-splash bucket can be discharged in time and is not easy to enter the BOG pipeline through the anti-splash bucket. Attached Figure Description

[0013] Figure 1 This is a cross-sectional schematic diagram of the anti-splash-in structure of the BOG pipeline in the large marine LNG storage tank described in this utility model.

[0014] Figure 2 This is a bottom view schematic diagram of the anti-splash structure for the BOG pipeline in the large marine LNG storage tank described in this utility model. Detailed Implementation

[0015] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings.

[0016] like Figure 1 , Figure 2 As shown, the BOG pipeline anti-splash structure in a large marine LNG storage tank includes: BOG pipeline 1, a protective cover 3 located in the storage tank 2 and welded to the outer wall of the BOG pipeline 1 inlet, the protective cover 3 and BOG pipeline 1 are arranged coaxially, the opening of the protective cover 3 faces downward and is lower than the inlet of BOG pipeline 1, and a splash shield 4 is set below the inlet of BOG pipeline 1, which is coaxial with it. The large opening of the splash shield 4 faces upward and the small opening faces downward. The diameter of the large opening of the splash shield 4 is larger than the diameter of the inlet of BOG pipeline 1. The front, back, left and right sides of the splash shield 4 are fixed to the protective cover 3 by a connecting rod 5. The splash shield 4 can prevent a large amount of LNG in the storage tank 2 from splashing into the BOG pipeline 1, and the LNG flowing into the splash shield 4 can leave through the small opening at the bottom of the splash shield 4.

[0017] In this embodiment, the protective cover 3 is a circular cover, and the splash guard 4 is a circular splash guard, as circular shapes are easier to manufacture. The clearance height A between the top of the splash guard 4 and the bottom of the BOG pipe 1 is 30-50cm, preferably 40cm. This design serves two purposes: preventing splashing and providing sufficient space for BOG flow. The diameter of the large opening at the top of the splash guard 4 is 2-3 times the inner diameter of the BOG pipe 1. If the diameter of the large opening at the top of the splash guard 4 is too small, it will not be able to prevent splashing; if the diameter is too large, it will make the splash guard too heavy. The distance B between the inlet of the BOG pipe 1 and the inner wall of the top of the protective cover 3 is at least greater than 30cm, which also facilitates BOG flow. The taper α of the splash guard 4 is 10-20 degrees, preferably 15 degrees. If the taper α is too small, LNG will not be able to drain from the splash guard 4 in time; if the taper α is too large, it will increase the impact force of LNG on the splash guard 4, making the splash guard 4 prone to deformation. The diameter of the bottom opening of the shield 3 is 200-260 cm larger than the outer diameter of the splash shield 4 to facilitate the flow of BOG. ​​The diameter of the small opening at the bottom of the splash shield 4 is 10-20 cm. If the small opening is too small, the LNG will not be able to be discharged from the splash shield 4 in time; if the small opening is too large, it will not be able to prevent splashing.

Claims

1. A splash-in prevention structure for a BOG line in a large marine LNG tank, comprising: The BOG pipeline is characterized by further comprising: a protective cover located in the storage tank and welded and fixed to the outer wall of the BOG pipeline inlet; the protective cover and the BOG pipeline are arranged coaxially; the opening of the protective cover faces downward and is lower than the BOG pipeline inlet; a splash guard coaxially arranged below the BOG pipeline inlet is provided; the larger opening of the splash guard faces upward and the smaller opening faces downward; the diameter of the larger opening of the splash guard is larger than the diameter of the BOG pipeline inlet; the front, back, left, and right sides of the splash guard are fixed to the protective cover by a connecting rod; the splash guard can prevent a large amount of LNG in the storage tank from splashing into the BOG pipeline; the LNG flowing into the splash guard can leave through the smaller opening at the bottom of the splash guard.

2. The BOG piping splash-proof structure in a large-sized marine LNG storage tank according to claim 1, characterized by: The protective cover is a circular cover, and the splash guard is a circular splash guard.

3. The BOG piping splash-in prevention structure in a large-sized marine LNG tank according to claim 1 or 2, characterized by: The gap between the top of the splash guard and the bottom of the BOG pipe should be 30-50cm.

4. The BOG piping splash-in prevention structure in a large-sized marine LNG storage tank according to claim 1 or 2, characterized by: The diameter of the large opening at the top of the splash guard is 2 to 3 times the inner diameter of the BOG pipe.

5. The BOG piping splash-in prevention structure in a large-sized marine LNG storage tank according to claim 1 or 2, characterized by: The distance between the BOG pipe inlet and the inner wall of the top of the cover should be at least 30cm.

6. The BOG piping splash-in prevention structure in a large-sized marine LNG storage tank according to claim 1 or 2, characterized by: The taper of the splash guard is 10 to 20 degrees.

7. The BOG piping splash-in prevention structure in a large-sized marine LNG storage tank according to claim 1 or 2, characterized by: The opening at the bottom of the protective cover is 200-260 cm larger than the outer diameter of the splash guard.

8. The BOG piping splash-in prevention structure in a large-sized marine LNG storage tank according to claim 1 or 2, characterized by: The diameter of the small opening at the bottom of the splash guard is 10-20cm.

Images