KR101917185B1 - Liquefied cargo containment tank - Google Patents

Abstract

The liquefied cargo storage tank according to an embodiment of the present invention includes a tank body 10 in which liquefied natural gas is stored, a ventilation layer 12 surrounding the outside of the tank body 10, a ventilation layer 12, (10) to the air-permeable layer (12), the air-permeable layer (12) and the insulating layer (14) And a gas discharging unit 200 for discharging the liquefied gas to the outside.

Description

{LIQUEFIED CARGO CONTAINMENT TANK}

The present invention relates to a liquefied gas storage tank, and more particularly to a liquefied gas storage tank for storing a liquefied gas such as liquefied natural gas.

In general, Liquefied Natural Gas (LNG) refers to a colorless transparent cryogenic liquid that reduces the volume of methane-based natural gas to -163 ° C and reduces its volume by one-sixth.

As such liquefied natural gas is used as an energy source, a liquefied cargo vessel capable of transporting liquefied natural gas liquefied by a large volume of natural gas has been developed. This liquefied cargo ship is equipped with a liquefied cargo storage tank capable of storing and storing liquefied natural gas liquefied at a cryogenic temperature.

Liquefied cargo storage tanks can be classified into independent type and membrane type depending on whether the load of liquefied cargo is directly applied by the heat insulating material. In the case of the independent type, Type A, Type B and Type C. ≪ / RTI >

Typically, stand-alone storage tanks are constructed from polyurethane insulation panels or spray insulation in the exterior of storage tanks made of aluminum, stainless steel, 9% nickel steel, etc. to protect cryogenic liquefies from external heat.

In such a liquefied cargo storage tank, the liquefied cargo in the tank may leak to the outside due to cracks or the like. In the case of Type B stand-alone tanks, it is possible to detect the leakage gas of the tank and to accommodate the leakage by applying an insulation panel system with a structure capable of collecting such leakage in a separate collection space.

However, in this case, it takes a lot of time and money to construct an insulation panel system.

Spray insulation system has advantages of simple construction and low cost, but it has a disadvantage that leakage gas detection and leakage can not be accepted.

Therefore, there is a need for a spray insulation system capable of detecting leakage gas and accommodating the leakage liquid.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and it is an object of the present invention to quickly and easily detect leak gas or leakage liquid on the surface of a tank and to discharge it to the outside, The present invention provides a liquefied cargo storage tank which is constructed so as to be able to perform a liquefied cargo storage tank.

The liquefied cargo storage tank according to an embodiment of the present invention includes a tank body 10 in which liquefied natural gas is stored, a ventilation layer 12 surrounding the outside of the tank body 10, a ventilation layer 12, (10) to the air-permeable layer (12), the air-permeable layer (12) and the insulating layer (14) And a gas discharging unit 200 for discharging the liquefied gas to the outside.

The ventilation layer 12 may have an open cell structure, and the insulation layer 14 may have a closed cell structure.

Preferably, the ventilation layer 12 is an adiabatic panel having an air-permeable heat-insulating foam or ventilating structure such as a soft urethane foam, and the heat-insulating layer 14 may be a water-tight and air-tight rigid urethane foam.

The gas discharge unit includes a first pipe 21 installed to pass through the heat insulating layer 14 and having one end located on the outer side of the heat insulating layer 14 and the other end located on the airflow layer 12, A valve 27 connected to the first pipe 21 and a gas detector 26 connected to the second pipe 22. The second pipe 22 is branched from the first pipe 21,

A first horizontal portion 23 which surrounds the outer surface of the first pipe 21 and has one side in contact with the heat insulating layer 14, a first horizontal portion 23 which is spaced apart from the first horizontal portion 23, A second horizontal portion 24 surrounding the outer surface of the second horizontal portion 24 and having one side in contact with the air-permeable layer 12, a plurality of second horizontal portions 24 extending from the lower surface of the second horizontal portion 24 to the inside of the air- And a first vertical portion 25 of the first substrate 20.

The plurality of first vertical portions 25 may be spaced apart from each other by a predetermined distance and may be disposed to surround the first pipe 21.

Such liquefied cargo storage tanks may be Type C stand-alone tanks.

And further includes a gas injection unit 202 disposed so as to be spaced apart from the gas discharge unit 200 and penetrating the ventilation layer 12 and the heat insulating layer 14 and injecting gas into the ventilation layer 12 can do.

The gas injection unit 202 is connected to the main pipe 31 passing through the heat insulating layer 14 and the ventilation layer 12 and connected to a pipe through which the gas is injected, And a valve 35 for turning on and off the injection.

The gas may be nitrogen.

Such liquefied cargo storage tanks may be Type B stand-alone tanks.

The gas discharge unit 200 may be located on the upper portion of the independent tank and the gas injection unit 202 may be located on the lower or the side of the independent tank.

A plurality of the gas discharging units 200 may be installed.

And may further include at least one support portion 40 disposed at a lower portion of the tank body 10 and supporting the tank body 10. [

FRP coating can be applied to the boundary between the air-permeable layer 12 and the heat insulating layer 14.

According to one embodiment of the present invention, the liquefied natural gas leaked from the tank body 10 can be collected in the space of the heat insulating member.

Therefore, the leakage gas leaked from the tank body 10 or the leakage liquid can be stably collected without installing the drip tray outside the heat insulating member 100.

The leaking gas or leaking liquid collected in the heat insulating member 100 can be quickly and easily detected using the gas discharging unit 200 and can be detected by injecting nitrogen gas or the like at room temperature through the gas injecting unit 202 And can be discharged to the outside.

1 is a schematic cross-sectional view of a liquefied cargo storage tank according to one embodiment of the present invention.
2 is a schematic perspective view of a gas discharge portion according to an embodiment of the present invention.
3 is a schematic cross-sectional view of the gas discharge portion of Fig.
4 is a schematic cross-sectional view of a liquefied cargo storage tank according to another embodiment of the present invention.
5 is an enlarged view of the support shown in Fig.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals are used for like elements in describing each drawing.

And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

1 is a schematic cross-sectional view of a liquefied cargo storage tank according to one embodiment of the present invention.

1, a liquefied cargo storage tank 1000 according to an embodiment of the present invention includes a tank body 10 in which liquefied natural gas is stored, a heat insulating member 100 surrounding the tank body 10, And a gas discharging portion 200. This liquefied storage tank 1000 may be located on a ship. The liquefied storage tank 1000 may be supported by a plurality of supports (not shown) installed on the ship.

The liquefied storage tank 1000 may be a Type C stand-alone tank, preferably a cylinder type whose cross section is circular. Accordingly, the support portion (not shown) may have a concave shape to surround the lower portion of the liquefied storage tank 1000.

The tank body 10 can be formed of a material that can withstand extremely low temperatures. For example, the tank body 10 may be formed of aluminum steel, stainless steel, 35% nickel steel, or the like. Therefore, the tank main body 10 can stably store the liquefied natural gas having a boiling temperature higher than atmospheric pressure and a boiling temperature of about-163.

The heat insulating member (100) is located outside the tank body (10) and is formed so as to surround the tank body (10). The heat insulating member 100 is for maintaining the state of liquefied natural gas and blocks heat and moisture which are transmitted from the inside to the outside or from the outside to the inside.

The thermal insulation member 100 includes a ventilation layer 12 located above the tank body 10 and a thermal insulation layer 14 located above the ventilation layer 12. The ventilation layer 12 may be formed to directly contact the outer surface of the tank body 10 with no gap between the tank body 10.

The ventilation layer 12 is a breathable structure, and the heat insulating layer 14 can form a watertight and airtight structure.

For example, the ventilation layer 12 may be an adiabatic foam having an air-permeable insulating foam or a vent structure such as a soft urethane foam, and the adiabatic layer 14 may be a water-tight and air-tight rigid urethane foam. At this time, the ventilation layer 12 has an open cell structure, and neighboring pores are connected to form a passageway through which leak gas easily flows and can be discharged to the outside. The heat insulating layer 14 has a closed cell structure, and the pores are surrounded by the partition walls to maintain the independent shape. Therefore, the pores adjacent to the pores are not connected to each other to form a watertight and airtight structure.

Specifically, the ventilation layer 14 is a ventilation structure for detecting and detecting leakage gas or leakage liquid, and the heat insulation layer 14 performs a secondary barrier function for blocking heat insulation and leakage gas or leakage liquid.

The FRP coating may be applied to the boundary between the ventilation layer 12 and the insulating layer 14 to increase the watertightness and airtightness, preferably for the leakage gas or the leakage of the leakage liquid.

The gas discharge unit 200 discharges the leakage gas leaking from the tank body 10 to the tank accommodation space of the hull and can be discharged out of the hull through a separate ventilation system or stored in a separate storage system.

FIG. 2 is a schematic perspective view of a gas discharge portion according to an embodiment of the present invention, and FIG. 3 is a schematic cross-sectional view of a gas discharge portion of FIG.

2 and 3, the gas discharging unit 200 is branched from the first pipe 21 and the first pipe 21 inserted through the heat insulating layer 14 to the ventilation layer 12, And a second pipe (22) located outside the storage tank (1000).

A valve 27 is provided at one end of the first pipe 21 to turn on / off the discharge of the leaking gas moving inside the first pipe, and the other end is inserted into the ventilation layer 12. The second pipe 22 is provided with a gas detector 26.

The first pipe 21 is provided with a first pipe 21 and a second pipe 21 which serve to prevent the leakage gas or the leakage liquid from leaking into the gap even if a gap due to a difference in heat shrinkage between the first pipe 21 and the heat insulating member 100 occurs. One horizontal portion 23 and a second horizontal portion 24 may be formed.

The first horizontal portion 23 and the second horizontal portion 24 may be in the form of a flange having a plate-like structure formed to surround the outer circumferential surface of the first pipe 21.

The first horizontal part 23 and the second horizontal part 24 are spaced apart from each other along the longitudinal direction of the first pipe 21. The first horizontal part 23 is located on the outer surface of the heat insulating layer 14, The second horizontal portion 24 may be located between the ventilation layer 12 and the heat insulating layer 14. One surface of the first horizontal portion 23 is in contact with one surface of the heat insulating layer 14 and one surface of the second horizontal portion 24 is in contact with one surface of the air permeable layer 12.

And further includes a first vertical portion 25 connected to the lower portion of the second horizontal portion 24 to facilitate movement of the leakage gas by separating the first pipe 21 and the tank body 10. [

The first vertical portion 25 extends in a direction perpendicular to the lower surface of the second horizontal portion 24, that is, in a direction parallel to the direction in which the first pipe 21 is inserted. The first vertical part 25 may be formed in plural and may be disposed to surround the other end of the first pipe 21 at a predetermined distance so as to facilitate the movement of the leakage gas in the ventilation layer 12. At this time, the first pipe 21 may be disposed at a certain distance from the other end.

As in the embodiment of the present invention, when the gas discharging part 200 is formed, the leakage gas or the leakage liquid can be detected quickly and easily, and can be discharged to the outside.

Gas or leaking liquid leaking from the tank body 10 may be stored in the ventilation layer 12 after being introduced into the ventilation layer 12. The ventilation layer 12 is an open cell structure and the leaking gas or leaking liquid travels through the interior of the ventilation layer 12 and then flows through the first pipe 21 and the second pipe 22 to the gas detector 26 (See arrows).

In this way, when gas is detected through the gas detector 26, the valve 27 is opened to discharge the leaked gas to the outside (see arrows). In an embodiment of the present invention, since the ventilation layer 12 is formed in an open cell structure, the leakage gas can be easily moved and discharged.

The gas discharged to the outside can be discharged to the outside of the hull through a ventilation system or stored in a separate storage system.

4 is a schematic cross-sectional view of a liquefied cargo storage tank according to another embodiment of the present invention.

The structure of the liquefied cargo storage tank of Fig. 4 is substantially the same as that of the liquefied cargo storage tank of Figs. 1 to 3, and therefore only the other parts will be described in detail.

4, the liquefied cargo storage tank 1002 according to another embodiment of the present invention includes a tank body 10, a ventilation layer 12, and a heat insulation layer 14, which are located in the hull 1 (100) and a gas discharging part (200).

The liquefied cargo storage tank 1002 according to the present embodiment may be a Type B independent tank. The tank body 10 has a polygonal cross section, and may be, for example, a rectangular parallelepiped structure in which the lower portion is chamfered. The upper and lower portions of the tank body 10 may have a flat surface. Hereinafter, the portion having the upper flat surface will be referred to as the upper plate, and the portion having the lower flat surface will be referred to as the lower plate.

The gas discharging unit 200 may be installed in the upper plate, and may be installed at a plurality of intervals.

Meanwhile, the liquefied storage tank 1002 of FIG. 4 further includes a gas injection unit 202 located apart from the gas discharge unit 200. The gas injection unit 202 may be installed at a lower side or a side plate connecting the upper and lower plates.

The gas injection unit 202 may have the same structure as the gas discharge unit 200 except for the second pipe. Specifically, the gas injection unit 202 includes a main pipe 31 connected to a pipe for supplying gas from the outside, a third horizontal unit 32 and a fourth horizontal unit 33 surrounding and supporting the main pipe 31, And a plurality of second vertical portions 34 connected to the lower surface of the fourth horizontal portion 33 and extending in a direction parallel to the main pipe 31. The main pipe 31 is connected with a valve 35 for turning on and off the injection of the gas.

The gas injection unit 202 can inject nitrogen gas from the outside into the air-permeable layer 12.

When the tank body 10 is cracked and the internal storage material leaks into the liquid state, it may be collected in the open cell of the ventilation layer 12, but unlike the gas, the gas located in the upper part of the tank body 10 The movement to the discharge portion 100 may not be easy. Particularly, when cracks are generated in the lower part of the tank body 10, it is not easy for the leakage liquid to move to the gas outlet 200 located at the upper part.

Therefore, when the nitrogen gas is injected from the outside as in the embodiment of the present invention, the leakage liquid evaporates and moves by the nitrogen gas, and can easily move to the gas discharging unit 200 and be discharged to the outside.

On the other hand, the tank body 10 can be supported by the support portion 40.

5 is an enlarged view of the support shown in Fig. Fig. 5 (a) is an enlarged view of a vertical supporting portion, and Fig. 5 (b) is an enlarged view of a rolling and pitching supporting portion.

5, the support portion 40 for supporting the lower portion of the tank body 10 is provided on the first support portion 41 and the first support portion 41 fixed to the hull 1 (see Fig. 4) A second support portion 42, and a third support portion 43 located within the heat insulating layer 14. [ The second support portion 42 and the third support portion 43 may be made of the same material such as wood. However, the material of the second support portion 42 and the third support portion 43 is not limited thereto, and may be formed of various materials.

The lower surface of the third support portion 43 may have an extended portion 43a extending in parallel with one surface of the heat insulating layer 14. [ The extended portion 43a prevents the leakage gas and the leakage liquid from leaking into the gap between the third supporting portion 43 and the heat insulating layer 14.

A guide portion 44 extending in the direction of the third support portion 43 and guiding the third support portion 43 may be installed on the lower portion of the tank body 10. The guide portion 44 may be formed to be surrounded by the ventilation layer 12

The vertical support portion 40 may be provided between the second support portion 42 and the third support portion 43 and may include a protection member 45 covering the second support portion 42. The protection member 45 can prevent the second support portion 42 and the third support portion 43 from being damaged by friction and can be formed of stainless steel.

A block sheet 4 for structural reinforcement can be positioned between the lower portion of the tank body 10 and the support portion 40.

The present invention has been described above with reference to the embodiments shown in the drawings. However, the present invention is not limited thereto, and various modifications or other embodiments falling within the scope of the present invention are possible by those skilled in the art. Accordingly, the true scope of protection of the present invention should be defined by the following claims.

1: Hull 10: Tank body
12: ventilation layer 14: insulating layer
40: support part 100:
200: gas discharge part 202: gas injection part

Claims (15)

A tank main body 10 in which liquefied natural gas is stored;
A ventilation layer (12) surrounding the outside of the tank body (10) and having a breathable structure;
A heat insulating layer 14 surrounding the outside of the ventilation layer 12 and having a watertight and airtight structure; And
A gas discharging part 200 formed to penetrate through the ventilation layer 12 and the heat insulating layer 14 and to discharge the liquefied natural gas leaking from the tank body 10 to the ventilation layer 12 to the outside;
Lt; / RTI >
The gas exhaust part 200
A first pipe (21) installed through the heat insulating layer (14), the first pipe (21) having one end located on the outer side of the heat insulating layer (14) and the other end located on the ventilation layer (12);
A second pipe (22) branched to detect the leaked liquefied natural gas from the first pipe (21);
A valve (27) connected to the first pipe (21) for regulating external discharge of the leaked liquefied natural gas; And
A gas detector (26) connected to the second pipe (22);
And it includes a
The first pipe 21 surrounds the outside of the first pipe 21 and comes into contact with the heat insulating layer 14 to generate a gap due to a difference in heat shrinkage between the first pipe 21 and the heat insulating layer 14, A first horizontal portion 23 of a plate shape for preventing the first horizontal portion 23 from leaking out;
The first pipe 21 is spaced apart from the first horizontal part 23 and surrounds the outer surface of the first pipe 21. One surface of the first pipe 21 is in contact with the ventilation layer 12, A second horizontal portion 24 in the form of a plate which interrupts leakage of the liquefied natural gas due to a gap due to a shrinkage difference; And
A plurality of first vertical portions (25) extending from a lower surface of the second horizontal portion (24) to the inside of the ventilation layer (12);
Wherein the liquefied cargo storage tank further comprises: The method according to claim 1,
Wherein the ventilation layer (12) has an open cell structure, and the heat insulating layer (14) has a closed cell structure. 3. The method of claim 2,
The ventilation layer 12 is an adiabatic panel having an air-permeable heat-insulating foam or a ventilation structure such as a soft urethane foam,
Wherein the heat insulating layer (14) is a hard urethane foam having watertightness and airtightness. delete delete The method according to claim 1,
Wherein the plurality of first vertical portions (25) are spaced apart from each other at a predetermined interval, and are arranged to surround the first pipe (21). The method according to claim 1,
Wherein the liquefied cargo storage tank is a Type C independent tank. The method according to claim 1,
A gas injection unit 202 disposed to be spaced apart from the gas exhaust unit 200 and penetrating the air vent layer 12 and the heat insulating layer 14 and injecting gas into the air vent layer 12,
Wherein the liquefied cargo storage tank further comprises: 9. The method of claim 8,
The gas injection unit 202
A main pipe (31) passing through the heat insulating layer (14) and the ventilation layer (12) and connected to a pipe through which the gas is injected; And
A valve 35 connected to the main pipe 31 to turn on and off the injection of the gas;
Wherein the liquefied cargo storage tank comprises: 10. The method of claim 9,
Characterized in that the gas is nitrogen. 10. The method of claim 9,
Wherein the liquefied cargo storage tank is a Type B independent tank. 12. The method of claim 11,
The gas discharge unit 200 is located above the Type B independent tank,
Wherein the gas injection unit (202) is located on the lower side or the side of the Type B independent tank. 13. The method of claim 12,
Wherein a plurality of the gas discharging units (200) are provided. The method according to claim 1 or 8,
At least one support portion (40) located at a lower portion of the tank body (10) and supporting the tank body (10)
Wherein the liquefied cargo storage tank further comprises: The method according to claim 1 or 8,
Wherein a FRP coating is applied to the boundary between the ventilation layer (12) and the heat insulating layer (14).

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