KR20200144178A - Insulation System of Liquefied Natural Gas Storage Tank - Google Patents

Abstract

An objective of the present invention is to improve productivity when constructing a liquefied natural gas (LNG) storage tank. An insulation system of an LNG storage tank including a liquid dome formed on in upper portion of the rear side toward the stern comprises: a sealing wall consisting of a metal membrane to seal LNG stored in the LNG storage tank; and an insulation wall installed on the outside of the sealing wall for insulation of the LNG. The insulation wall includes: insulation boxes arranged around the liquid dome and the edge of the inner wall of the LNG storage tank; and insulation panels arranged on an area other than the area on which the insulation boxes are arranged on the inner wall of the LNG storage tank. The insulation wall formed between the liquid dome and the rear wall of the LNG storage tank is formed by only a combination of the insulation boxes without arranging the insulation panels.

Description

LNG storage tank insulation system {Insulation System of Liquefied Natural Gas Storage Tank}

The present invention relates to an insulation system for an LNG storage tank, and more particularly, in which the primary and secondary insulation walls are provided with a panel-type insulation layer made of polyurethane foam, while the secondary sealing wall is constituted by a flat flat inbar membrane. It is possible, and it relates to an insulation system for an LNG storage tank that aims to improve productivity by simplifying the insulation structure at the periphery of the liquid dome as much as possible.

Natural gas is transported in gaseous form through gas pipelines on land or sea, or stored in LNG carriers as liquefied natural gas (LNG) and transported to remote consumers. LNG is obtained by cooling natural gas to cryogenic temperatures (approximately -163°C), and its volume is reduced to about 1/600 compared to that of gaseous natural gas, so it is very suitable for long-distance transportation through sea.

Storage tanks that can withstand the cryogenic temperatures of LNG (commonly referred to as'cargo hold') are installed in structures for transporting or storing LNG, such as LNG carriers for loading and unloading LNG to land-requiring destinations by operating the sea with LNG.

LNG storage tanks can be classified into Independent Tank Type and Membrane Type, depending on whether the load of cargo directly acts on the insulation material. Usually, the membrane type storage tank is divided into GTT's NO 96 type and MARK Ⅲ type, and the independent tank type storage tank is divided into MOSS type and IHI-SPB type.

Among the membrane-type storage tanks, the NO 96-type storage tank includes primary and secondary sealing walls made of Invar (36% nickel steel) membranes with a thickness of 0.5 to 0.7 mm, and perlite in a plywood box. It includes primary and secondary insulation walls provided in the form of insulation boxes filled with insulation materials such as powder.

The NO 96 type storage tank has almost the same degree of liquid tightness and strength as the primary and secondary sealing walls, so when the primary sealing wall leaks, it can safely support the cargo with only the secondary sealing wall for a considerable period of time.

In addition, since the NO 96 type storage tank is a type of insulation wall filled with insulation material inside a wooden box, it can have high compressive strength and rigidity compared to the MARK Ⅲ type storage tank, and it is easy to weld and has high automation rate.

On the other hand, the MARK Ⅲ type storage tank consists of a primary sealing wall made of a 1.2mm thick stainless steel (SUS) membrane, a secondary sealing wall made of a rigid triplex, and a polyurethane foam. It includes primary and secondary insulation walls provided with an insulation panel in which plywood plywood is adhered to the top or bottom.

The primary sealing wall of the MARK III type storage tank has corrugated corrugations to absorb heat shrinkage caused by LNG in cryogenic conditions, and since these corrugated corrugations absorb the deformation of the membrane, there is no significant stress in the membrane.

However, in the MARK Ⅲ type storage tank, it is difficult to apply a corrugated stainless steel membrane for the secondary sealing wall because of the interference with the insulation walls arranged at the top and bottom, and the insulation panel that forms an insulation layer by a combination of polyurethane foam and plywood. Due to the characteristics of the NO 96 type storage tank, it is difficult to apply an Invar membrane with a small coefficient of heat shrinkage, so a triplex is usually used instead of a metal membrane. This structure has a disadvantage of lower stability than the NO 96 type storage tank. have.

In addition, the MARK Ⅲ type storage tank is disadvantageous in terms of installation/manufacturing due to low welding automation rate of the primary sealing wall with corrugation, but the cost of stainless steel membrane and triplex is cheaper than Invar membrane and construction is simple. Polyurethane foam is widely used with NO 96 type storage tanks because of its excellent insulation effect.

Accordingly, the technical problem to be achieved by the present invention is to provide the primary and secondary thermal insulation walls of the LNG storage tank with a panel-type thermal insulation layer made of polyurethane foam, while providing the secondary sealing wall with a metal membrane. Another new type of LNG storage tank insulation system is to be provided.

In addition, in providing a new type of LNG storage tank insulation system, another technical task is to improve productivity in the construction of LNG storage tanks by simplifying the insulation structure of the periphery of the liquid dome provided in the LNG storage tank as much as possible. To

In order to achieve the above object, the present invention is an insulation system for an LNG storage tank including a liquid dome formed on the rear side in the stern direction, and is made of a metal membrane and stored in the LNG storage tank. A sealing wall for sealing LNG; And an insulating wall installed outside the sealing wall for insulating the LNG, wherein the insulating wall comprises: an insulating box disposed around an edge of an inner wall of the LNG storage tank and a periphery of the liquid dome; And an insulation panel disposed on an inner wall of the LNG storage tank in an area other than the area in which the insulation box is disposed, wherein the insulation wall formed between the liquid dome and the rear wall of the LNG storage tank comprises the insulation panel LNG storage tank, characterized in that it is made only by a combination of the insulation box without the arrangement of, and the insulation panel is a sandwich panel including a foam insulation material, and has lower rigidity than the insulation box made of a plywood box. Insulation system of

The insulation box is provided in a form filled with an insulation material made of pearlite powder or glass wool inside the plywood box, and the insulation panel is made of an insulation material made of polyurethane foam (PUF) or glass fiber reinforced polyurethane foam (R-PUF). A protective plate made of plywood or fiber-reinforced plastic may be attached to at least one of the upper and lower surfaces.

The insulation wall further includes a space insulation material inserted into a boundary portion facing the insulation box and the insulation panel, and the rigidity of the space insulation is smaller than the rigidity of the insulation box and greater than the rigidity of the insulation panel, the Structural rigidity of the insulating box, the space insulating material, and the insulating layer arranged in the order of the insulating panel may be sequentially formed.

The space insulation material may have intermediate rigidity between the insulation box and the insulation panel.

The sealing wall may include a primary sealing wall that primarily seals the LNG; And a secondary sealing wall secondaryly sealing the LNG, wherein the insulation wall comprises: a primary insulation wall disposed between the primary sealing wall and the secondary sealing wall; And a secondary insulation wall disposed between the secondary sealing wall and the inner wall of the hull, wherein the secondary insulation wall formed in the space between the liquid dome and the rear wall of the LNG storage tank comprises: A single or a plurality of secondary insulation boxes are arranged along the longitudinal direction, and the primary insulation wall formed in the space between the liquid dome and the rear wall of the LNG storage tank defines the longitudinal direction of the LNG storage tank. Accordingly, a plurality of primary insulation boxes are arranged and configured, and the first insulation box and the second insulation box may be intersected.

At this time, the boundary between the adjacent first insulating boxes may be arranged to be shifted from the ends of the second insulating box.

In addition, another aspect of the present invention for achieving the above object, in the insulation system of the LNG storage tank including a liquid dome (liquid dome) formed on the rear side in the stern direction, components constituting the insulation wall As, an insulation box in the form of a heat insulating material is filled inside the plywood box; And a heat insulation panel in the form of a protective plate attached to at least one of the upper and lower surfaces of the polyurethane foam, made of plywood or fiber-reinforced plastic, between the liquid dome and the front wall and side walls of the LNG storage tank, The insulation box is disposed along the circumference of the liquid dome and the circumference of the inner wall of the LNG storage tank, and the insulation panel is disposed in a space where the insulation box is not disposed, thereby forming an insulation wall, and the liquid dome and the LNG It provides an insulation system for an LNG storage tank, characterized in that between the rear walls of the storage tank, the insulation wall is formed only by the combination of the insulation box without the arrangement of the insulation panel.

The insulating wall formed between the rear wall of the LNG storage tank and the liquid dome includes at least one secondary insulating box and a plurality of primary insulating boxes disposed inside the secondary insulating box, and the secondary The insulation box and the primary insulation box may be intersected.

The insulating wall formed between the liquid dome and the front wall and the side wall of the LNG storage tank further includes a spatial insulating material inserted into a boundary portion where the insulating box and the insulating panel face each other, and the spatial insulating material is the insulating box And may have intermediate rigidity of the insulation panel.

The insulation system of an LNG storage tank according to the present invention is a conventional method in which the primary and secondary insulation walls of the LNG storage tank are provided with a panel-type insulation layer made of polyurethane foam, while the secondary sealing wall is constituted by a metal membrane. Provides an entirely new type of LNG storage tank insulation system.

Accordingly, in the present invention, it is possible to provide both the primary and secondary sealing walls with metal membranes while configuring the primary and secondary insulation walls as insulation panels made of polyurethane foam, resulting in excellent insulation performance and stability. There is an improvement effect.

In addition, according to the present invention, as the flat invar membrane is applied as the secondary sealing wall, the welding line is formed in a straight line when the secondary sealing wall is installed, so that welding can be automated, thereby improving productivity.

In addition, in the heat insulation system of the LNG storage tank according to the present invention, as the primary insulation wall and the secondary insulation wall are intersected with each other, and the structural rigidity of the insulation layer at the corner of the storage tank is sequentially arranged, the storage It is possible to flexibly cope with the step problem occurring at the boundary between the insulation box disposed at the corner of the tank and the insulation panel disposed in other areas, effectively preventing damage to the membranes of the primary and secondary sealing walls. I can.

In addition, the insulation system of the LNG storage tank according to the present invention has the effect of improving the productivity in drying the LNG storage tank by simplifying the insulation structure of the periphery of the liquid dome as much as possible.

1 is a perspective view showing the appearance of an LNG storage tank according to the present invention.
Figure 2 is a side cross-sectional view schematically showing the corner insulation system of the LNG storage tank according to the present invention.
3 is a perspective view showing a structure in which insulating walls are intersected in the LNG storage tank according to the present invention.
Figure 4 is an internal perspective view showing the insulating structure of the periphery of the liquid dome in the LNG storage tank according to the present invention.
5 is a side cross-sectional view schematically showing an insulating structure around a liquid dome of an LNG storage tank according to an embodiment of the present invention.
6 is a side cross-sectional view schematically showing an insulating structure around a liquid dome of an LNG storage tank according to another embodiment of the present invention.

In order to fully understand the present invention, the operational advantages of the present invention, and the objects achieved by the implementation of the present invention, reference should be made to the accompanying drawings illustrating preferred embodiments of the present invention and the contents described in the accompanying drawings.

Hereinafter, the present invention will be described in detail by describing a preferred embodiment of the present invention with reference to the accompanying drawings. The same reference numerals in each drawing indicate the same member.

In the present invention, the use of the terms'primary' and'secondary' refers to whether the LNG is primarily sealed or insulated based on the LNG stored in the storage tank, or the secondary is sealed or insulated. It was used as a classification standard for whether or not.

Also, by convention, the terms'upper' or'up' applied to an element of a tank refer to a direction toward the inside of the tank, regardless of the direction to gravity, and likewise, the term'lower' or'down' refers to gravity. Regardless of the direction, it refers to the direction toward the outside of the tank.

1 is a view showing the appearance of an LNG storage tank according to the present invention, Figure 2 is a side cross-sectional view schematically showing the corner insulation system of the LNG storage tank according to the present invention, Figure 3 is an LNG storage tank according to the present invention Is a perspective view showing a structure in which the insulating walls are intersected.

First, referring to FIG. 1, the LNG storage tank according to the present invention has an angle of approximately 135° on the upper and lower sides of the storage tank in order to reduce the sloshing load of LNG stored therein, particularly the sloshing load in the left and right direction. An inclined chamfer can be formed.

Referring to Figure 2, the LNG storage tank according to the present invention, a secondary insulating wall 100 made of a plurality of secondary insulating panels 110 arranged on the inner wall of the hull (H), and the secondary insulating wall ( 100) a secondary sealing wall 200 installed on the second sealing wall 200, a primary insulating wall 300 made of a plurality of primary insulating panels 310 arranged on the secondary sealing wall 200, and the primary insulating wall It can be seen that it is composed of an insulation system having a double barrier structure, including the primary sealing wall 400 installed on the 300.

The primary insulation panel 310 is manufactured as a unit panel in the form of a hexahedron or more polyhedron, and a plurality of primary insulation panels 310 are arranged on the secondary sealing wall 200 in the transverse and longitudinal directions, The insulating wall 300 may be formed.

The secondary insulation panel 110 is also manufactured as a unit panel in the form of a hexahedron or higher polyhedron, and a plurality of secondary insulation panels 110 are arranged in the transverse and longitudinal directions on the inner wall of the hull H to provide secondary insulation. Wall 100 can be formed.

The primary and secondary insulation panels 310 and 110 are plywood or composite materials on the top, bottom, or both of the top, bottom, or top and bottom surfaces of insulation materials such as polyurethane foam (PUF) or reinforced polyurethane foam (R-PUF). A protective plate made of (for example, fiber-reinforced plastic) may be provided as a sandwich panel to which it is bonded.

The secondary insulating wall 100 may be fixed to the inner wall of the hull H by an adhesive such as epoxy mastic or studs, and the primary insulating wall 300 may be connected to the secondary insulating wall 100. With the secondary sealing wall 200 interposed therebetween, the primary insulation panel 310 is coupled to a securing device provided on the secondary insulation panel 110, thereby forming the secondary sealing wall 200. ) Can be fixed in close contact with the top of the.

The primary and secondary sealing walls 400 and 200 may be formed of a metal membrane.

The primary and secondary sealing walls 400 and 200 may be formed by selectively adopting any one of various metal materials strong in low temperature brittleness, such as Invar, stainless steel (SUS), aluminum alloy, etc. , Flat or corrugated metal membranes.

In the present invention, as a preferred embodiment, the primary sealing wall 400 is made of a corrugation membrane made of stainless steel, and the secondary sealing wall 200 is LNG made of a flat membrane made of Invar material. Provide storage tanks.

The primary sealing wall 400 is to be sealed by direct contact with LNG, and may include a plurality of corrugations formed in a direction inside the storage tank on a stainless steel membrane, and the plurality of corrugations absorb shrinkage caused by cryogenic temperatures to prevent stress on the membrane. Prevents it from being concentrated.

The secondary sealing wall 200 may be formed of a flat invar membrane. Specifically, the secondary insulating wall 100 is formed by continuously welding a band-shaped metal plate called an invar strake to a tongue member installed on the upper side of the secondary insulating panel 110. The secondary sealing wall 200 may be installed on the top of the.

In the LNG storage tank according to the present invention, in order to provide the secondary sealing wall 200 as a flat invar membrane, a structure made of Invar steel is installed at the transverse corner of the storage tank. Can be.

As described above, in general, since the flat invar membrane has a small coefficient of heat shrinkage, it is not suitable to use an insulation panel made of polyurethane foam, that is, a panel type insulation layer as an insulation wall to support it. not. In order to apply the flat invar membrane, the insulating wall supporting the membrane, like a conventional NO 96 type storage tank, must be configured with an insulating box having low heat shrinkage deformation and high rigidity, that is, a box-type insulating layer.

However, the technical problem to be achieved by the present invention is to provide the primary and secondary thermal insulation walls 300 and 100 as a panel-type thermal insulation layer made of polyurethane foam, while providing the secondary sealing wall 200 with a metal membrane, especially flat. It is to provide an insulation system for a new type of LNG storage tank that can be configured with a flat Invar membrane in the form of a type, and an object of the present invention is a transverse connector (a structure made of Invar steel at the corner of the storage tank). This can be achieved by installing a transverse connector 500).

Specifically, the transverse connector 500 is a structure in the form of a grid installed along the edges of the front and rear walls of the storage tank, and is stored by welding one end to an anchoring bar provided on the inner wall of the hull H. It is fixedly installed at the transverse corner of the tank, and the other end supports each end of the primary sealing wall 400 and the secondary sealing wall 200, thereby transmitting various loads applied to them to the hull H. Plays a role.

In the present invention, a part of the load applied to the primary and secondary sealing walls 400 and 200 by the transverse connector 500 installed in the transverse corner of the storage tank is transferred to the hull H to be resolved. , It becomes possible to configure the secondary insulation wall 100 supporting the secondary sealing wall 200 provided with a flat inbar membrane as an insulation panel having weaker rigidity than an insulation box.

In other words, in the present invention, the rigidity of the secondary insulating wall 100 is supplemented by the transverse connector 500 installed at the transverse corner of the storage tank and supporting both ends of the secondary sealing wall 200, It is possible to apply a flat Invar membrane in a flat shape as the secondary sealing wall 200.

In addition, the present invention is a part of the configuration for applying the secondary sealing wall 200 as a flat inbar membrane, as a heat insulating material constituting the secondary insulation panel 110, high-density glass fiber higher than the density of about 130kg / m ³ Reinforced polyurethane foam (R-PUF) can be used.

Therefore, in the present invention, the secondary insulating wall 100 can be formed of an insulating panel made of polyurethane foam, and the secondary sealing wall 200 can be provided with a metal membrane, so that stability is improved. When the sealing wall 200 is installed, since the welding line is formed in a straight line, it is possible to automate welding, thereby improving productivity.

In addition, in the present invention, as the primary and secondary insulation walls 300 and 100 are made of polyurethane foam, the insulation performance becomes excellent. The LNG storage tank according to the present invention achieves the same or higher insulation effect while significantly reducing the thickness of the primary and secondary insulation walls compared to the conventional NO 96 type storage tank in which the insulation wall is provided only as an insulation box. I can.

On the other hand, in the LNG storage tank according to the present invention, the interior of the transverse connector 500 and between the transverse connector 500 and the hull H, high rigidity insulation to support the transverse connector 500 Box 510 is placed. The insulation box 510 may be provided in a form in which an insulation material such as perlite powder or glass wool is filled inside the plywood box.

Accordingly, the LNG storage tank according to the present invention is composed of insulation panels 310 and 110, in which most of the insulation walls 300 and 100 are made of polyurethane foam, but the insulation box 510 at the transverse corner of the storage tank It has a structure in which is mixed.

In this way, the structure in which the insulation box 510 is mixedly arranged at the corner portion can be similarly applied to the longitudinal corner portion of the storage tank. Therefore, the LNG storage tank according to the present invention is formed around the edge of each wall constituting the storage tank. A box-type insulation layer is disposed along the line, and a panel-type insulation layer is disposed in the inner direction of the edge.

However, at this time, the rigidity of the insulation box 510 installed at the corner of the storage tank is high, but the rigidity of the insulation panels 310 and 110 is low, so there is a difference in the degree of heat shrinkage between the insulation box 510 and the insulation panels 310 and 110. Occurs. Therefore, when heat shrinkage by cryogenic LNG, the heat insulation box 510 and the heat insulation panels 310, 110 due to the difference in structural integrity of the insulation box 510 and the insulation panels 310, 110, and the heat load and fluid force of the liquefied gas. ), a height step due to heat contraction occurs at the boundary between them, resulting in thermal stress in the sealing walls 400, 200 installed on the insulation walls 300, 100, and the membranes of the sealing walls 400, 200 are damaged. There is a risk of becoming.

In order to prevent this, the insulation system of the LNG storage tank according to the present invention includes, first, a primary insulation panel 310 constituting the primary insulation wall 300 and a secondary insulation panel constituting the secondary insulation wall 100. By intersecting each other, damage to the sealing walls 400 and 200 due to a step occurring at the boundary between the insulation box 510 and the insulation panels 310 and 110 is minimized.

Looking in more detail with respect to the cross-arrangement of the primary insulation panel 310 and the secondary insulation panel 110, as shown in Figure 3, the primary insulation panel 310 is the secondary insulation panel 110 and the transverse direction And it may be disposed to be displaced from the plurality of secondary heat insulating panels 110 disposed at the bottom so that all of the longitudinal ends do not match.

More preferably, the primary insulation panel 310 and the secondary insulation panel 110 are provided with the same width and length, and the four corners of the primary insulation panel 310 are the upper center of the secondary insulation panel 110 It may be disposed in a manner that is fixed to a fixing device provided in, and accordingly, one primary insulation panel 310 may be disposed to span the upper portions of the four secondary insulation panels 110 disposed below.

This cross-arrangement method of the primary insulation panel 310 and the secondary insulation panel 110 may be applied to the entire wall of the storage tank, and as shown in FIG. 2, it may also be applied to the corners of the storage tank. .

At this time, the insulation box 510 disposed at the level of the primary insulation wall 300 so that the cross arrangement of the primary insulation panel 310 and the secondary insulation panel 110 can be applied to the corner of the storage tank. Insulation box 510' (hereinafter referred to as'primary corner box') disposed closest to the primary insulation panel 310, and insulation box 510 disposed at the level of the secondary insulation wall 100 Among them, an insulation box 510 ″ (hereinafter referred to as “second corner box”) disposed closest to the secondary insulation panel 110 is disposed in a stepwise manner.

The primary corner box 510 ′ and the secondary corner box 510 ″ are protruding from the transverse connector 500 to be connected to the primary sealing wall 400 and the secondary sealing wall 200. It is a configuration disposed on the side of the transverse connector 500 to support.

In the stepwise arrangement of the first corner box 510' and the second corner box 510'', the length of the second corner box 510'' along the longitudinal direction of the storage tank is changed to the first corner box 510'. By making it longer, the secondary corner box 510 ″ may be configured to protrude more outward of the transverse connector 500 than the primary corner box 510 ′.

On the other hand, among the plurality of primary insulation panels 310 constituting the primary insulation wall 300, the primary insulation panels 310 disposed at the most corners of the storage tank include corner boxes 510 ′ and 510 ″. The length may be adjusted in consideration of the arrangement with the fields, and for example, the length may be formed to be somewhat shorter than that of the other primary insulation panels 310 disposed in an area other than the corner part. However, the present invention is not limited thereto, and proper arrangement at the corner is not limited by adjusting the length of the corner-side primary insulation panel 310, but by adjusting the length of the corner boxes 510' and 510'. It can be done.

Insulation system of an LNG storage tank according to the present invention, by intersecting the primary and secondary insulation panels 310 and 110 disposed adjacent to the insulation box 510, the insulation box 510 and the insulation panel 310 It is possible to prevent damage to the sealing walls 400 and 200 due to a step occurring at the boundary between the, 110). In the present invention, the cross-arrangement of the first and second heat insulating panels 310 and 110 extends a heat transfer path formed by a gap between the panels, thereby increasing heat insulation performance.

In addition, the insulation system of the LNG storage tank according to the present invention, in order to prevent damage to the sealing walls 400, 200 due to a step occurring at the boundary between the insulation box 510 and the insulation panels 310, 110, As shown in Fig. 2, between the corner boxes 510 ′ and 510 ″ and the insulation panels 310 and 110 installed at the corners of the storage tank, the corner boxes 510 ′ and 510 ″ and the insulation panels ( Space insulators 320 and 120 having intermediate rigidity of 310 and 110 are disposed.

More specifically, a primary space insulation material having an average amount of heat contraction between the primary corner box 510 ′ and the primary insulation panel 310 ′ and the primary insulation panel 310 ( 320), and between the secondary corner box 510 ″ and the secondary insulation panel 110, the secondary corner box 510 ″ and the secondary insulation panel 110 have an average amount of heat shrinkage. The space insulation 120 is disposed.

Accordingly, at the corners of the storage tank, corner boxes 510 ′ and 510 ″ having the greatest rigidity, space insulation materials 320 and 110 having intermediate rigidity, and thermal insulation panels 310 and 110 having the smallest rigidity These are arranged sequentially.

Therefore, according to the present invention, as the structural rigidity of the insulating layer at the corner of the storage tank is sequentially achieved, the insulating height according to the difference in the degree of heat shrinkage from the corner boxes 510 ′ and 510 ″ to the insulating panels 310 and 110 is increased. Since it can be made smoothly, the step difference at the connection part between the insulation box 510 and the insulation panels 310 and 110 is minimized, so that damage to the primary and secondary sealing walls 400 and 200 can be more effectively prevented. have.

In addition, in the present invention, by configuring the stiffness of the insulating layer constituting the secondary insulating wall 100 to be equal to or greater than the stiffness of the insulating layer constituting the primary insulating wall 300, the steps occurring at the boundary of the insulating layer are more efficiently reduced. Can be minimized.

On the other hand, the LNG storage tank is provided with a liquid dome as a passage for loading and unloading. The liquid dome is located at the top of the LNG storage tank and forms a part of the LNG storage tank as a passage for loading and unloading LNG.

Figure 4 is an internal perspective view showing the insulating structure of the periphery of the liquid dome in the LNG storage tank according to the present invention. For reference, FIG. 4 is a diagram showing the inside of the storage tank facing the top for convenience of explanation.

4, in the LNG storage tank according to the present invention, a liquid dome box forming a liquid dome is disposed close to the rear wall of the storage tank. That is, the liquid dome box is disposed on the rear side in the stern direction of the LNG storage tank.

In the LNG storage tank according to the present invention, as described above, the primary and secondary insulating walls 300 and 100 are intersected with each other, and the structural rigidity of the insulating layer at the corner of the storage tank is sequentially arranged to minimize the step difference. Also applies to the periphery of the liquid dome.

FIG. 5 schematically shows an insulating structure around a liquid dome of an LNG storage tank according to an embodiment of the present invention to which the above concept is applied.

5, in the LNG storage tank according to an embodiment of the present invention, primary and secondary insulation boxes 330 and 130 having high rigidity are disposed around the liquid dome 600, and the liquid dome 600 ) In a direction away from the primary and secondary space insulation materials 320 and 120, and the primary and secondary insulation panels 310 and 110 sequentially arranged.

Such an arrangement structure can be applied without a problem between the liquid dome 600 and the front wall of the storage tank (the right part of the liquid dome in FIG. 5), and between the liquid dome 600 and the side wall of the storage tank (not shown). have.

However, as shown on the left side of the liquid dome 600 in FIG. 5, there is not enough space for the insulation panel to be disposed between the liquid dome 600 and the rear wall of the storage tank, so when the above concept is applied as it is , In the corresponding space, corner boxes 510 ′ and 510'' disposed at the corners of the storage tank without insulation panels, space insulation 320 and 120, and insulation boxes 330 disposed at the periphery of the liquid dome 600, 130).

Specifically, the secondary insulating wall 100 formed between the liquid dome 600 and the rear wall of the storage tank is a secondary corner box 510 ″ from the lateral corner of the storage tank-secondary space insulation 120 )-The structure in which the secondary insulation box 130 is sequentially arranged, and the primary insulation wall 300 is a primary corner box 510' from the transverse corner of the storage tank-primary space insulation 320- A structure in which the primary insulation box 330-the primary space insulation material 320-the primary insulation box 330 is sequentially arranged is derived.

However, as described above, the space insulation materials 320 and 120 are configured to cope with the step difference occurring at the boundary between the insulation box 510 and the insulation panels 310 and 110. The liquid dome 600 and the storage tank Since the space between the rear walls is composed only of a box-type insulation layer without an insulation panel, a step does not occur between the boundaries, so there is no practical advantage to arrange the space insulation materials 320 and 120.

Therefore, the present invention, as shown in Figure 6, the primary and secondary insulation walls (300, 100) formed between the liquid dome 600 and the rear wall of the storage tank, the insulation panels (310, 110) Of course, even the space insulation (320, 120) is all removed and provides an insulation system for an LNG storage tank, characterized in that it consists of only the insulation box (330, 130).

In the present invention, the insulating box 510 provided to support the transverse connector 500 and the primary and secondary insulating boxes 330 and 130 disposed at the periphery of the liquid dome 600 are slightly different in size. There may be, but the inside of the plywood box may be provided in the same structure in the form of filling an insulating material such as pearlite powder or glass wool.

Therefore, in the embodiment shown in FIG. 6, a primary corner box 510 ′ and a secondary corner box provided to support the transverse connector 500 between the liquid dome 600 and the rear wall of the storage tank ( 510'') will be described in unifying the first insulation box 330 and the second insulation box 130, respectively.

In the LNG storage tank according to the present invention, the first insulating wall 300 and the second insulating wall 100 formed between the liquid dome 600 and the rear wall of the storage tank are, respectively, a first insulating box 330 and 2 It characterized in that it is made of only a box-type insulation layer, including only the car insulation box 130.

At this time, the secondary insulation wall 100 formed between the liquid dome 600 and the rear wall of the storage tank is composed of a single secondary insulation box 130 as shown in FIG. 6(a), or As shown in (b) of Figure 6 may be composed of a plurality of secondary insulation box 130.

In addition, the primary insulation wall 300 formed between the liquid dome 600 and the rear wall of the storage tank may be composed of a plurality of primary insulation boxes 330, wherein the primary insulation box 330 is 2 To be intersected with the vehicle insulation box 130. Cross-arrangement in this area means that the boundary between the neighboring primary insulation boxes 330 does not coincide with the end of the secondary insulation box 130 or the boundary between the secondary insulation boxes 130 that are adjacent to each other, Means that.

Figure 6 (a) and (b) is only one example of various embodiments of the present invention, the primary and secondary insulation boxes (330, 130) are provided in a larger number than that shown in FIG. Maybe. However, even according to another embodiment, it is preferable that the first insulating box 330 and the second insulating box 130 are intersected with each other.

The insulation system of the LNG storage tank according to the present invention has the effect of improving productivity in drying the LNG storage tank by simplifying the insulation structure of the periphery of the liquid dome 600 as much as possible.

It is obvious to those of ordinary skill in the art that the present invention is not limited to the described embodiments, and that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, it should be said that such modifications or variations belong to the claims of the present invention.

100: secondary insulation wall 110: secondary insulation panel
120: secondary space insulation 130: secondary insulation box
200: secondary sealing wall
300: primary insulation wall 310: primary insulation panel
320: primary space insulation 330: primary insulation box
400: primary sealing wall
500: transverse connector 510: insulation box
510': 1st corner box 510'': 2nd corner box
600: liquid dome

Claims (9)

In the insulation system of the LNG storage tank including a liquid dome (liquid dome) formed on the rear side in the stern direction,
A sealing wall made of a metal membrane to seal the LNG stored in the LNG storage tank; And an insulating wall installed outside the sealing wall for insulating the LNG,
The insulating wall,
Insulation boxes disposed along the periphery of the inner wall of the LNG storage tank and the periphery of the liquid dome; And an insulation panel disposed on an inner wall of the LNG storage tank in an area other than the area in which the insulation box is disposed,
The insulating wall formed between the liquid dome and the rear wall of the LNG storage tank is made only of a combination of the insulating box without the arrangement of the insulating panel,
The insulation panel is a sandwich panel comprising a foam insulation, characterized in that it has a lower rigidity than the insulation box made of a plywood box,
Insulation system of LNG storage tank. The method according to claim 1,
The insulation box is provided in a form filled with an insulation material made of pearlite powder or glass wool inside the plywood box,
The insulation panel is provided in a form in which a protective plate made of plywood or fiber-reinforced plastic is adhered to at least one of the upper and lower surfaces of an insulation material made of polyurethane foam (PUF) or glass fiber reinforced polyurethane foam (R-PUF). Characterized in that,
Insulation system of LNG storage tank. The method according to claim 2,
The insulating wall,
The insulation box and the insulation panel further comprises a space insulation material inserted and disposed at the boundary facing each other,
The stiffness of the space insulation is smaller than the stiffness of the insulation box and greater than the stiffness of the insulation panel, and the structural rigidity of the insulation layer disposed in the order of the insulation box, the space insulation material, and the insulation panel is sequentially formed. ,
Insulation system of LNG storage tank. The method of claim 3,
The space insulation material is characterized in that it has an intermediate rigidity between the insulation box and the insulation panel,
Insulation system of LNG storage tank. The method according to claim 2,
The sealing wall may include a primary sealing wall that primarily seals the LNG; And a secondary sealing wall secondaryly sealing the LNG,
The insulating wall may include: a first insulating wall disposed between the first sealing wall and the second sealing wall; And a secondary insulating wall disposed between the secondary sealing wall and the inner wall of the hull,
The secondary insulation wall formed in the space between the liquid dome and the rear wall of the LNG storage tank is configured by arranging a single or a plurality of secondary insulation boxes along the longitudinal direction of the LNG storage tank,
The primary insulation wall formed in the space between the liquid dome and the rear wall of the LNG storage tank is configured by arranging a plurality of primary insulation boxes along the longitudinal direction of the LNG storage tank,
The primary insulation box and the secondary insulation box, characterized in that the cross-arrangement,
Insulation system of LNG storage tank. The method of claim 5,
Characterized in that the boundary between the adjacent to each other the primary insulation box is disposed so as to deviate from the end of the secondary insulation box,
Insulation system of LNG storage tank. In the insulation system of the LNG storage tank including a liquid dome (liquid dome) formed on the rear side in the stern direction,
As a component constituting the insulation wall, the insulation box in the form of a heat insulation is filled inside the plywood box; And an insulation panel in the form of a protective plate attached to at least one of the upper and lower surfaces of the polyurethane foam, made of plywood or fiber-reinforced plastic,
Between the liquid dome and the front wall and side walls of the LNG storage tank, the insulation box is disposed along the circumference of the liquid dome and the inner wall edge of the LNG storage tank, and the insulation box is disposed in a space where the insulation box is not disposed. Insulation walls are formed by placing the panels,
Between the liquid dome and the rear wall of the LNG storage tank, characterized in that the heat insulation wall is formed only by the combination of the insulation box without the arrangement of the insulation panel,
Insulation system of LNG storage tank. The method of claim 7,
The insulating wall formed between the rear wall of the LNG storage tank and the liquid dome includes at least one secondary insulating box and a plurality of primary insulating boxes disposed inside the secondary insulating box,
Characterized in that the secondary insulation box and the primary insulation box are intersected
Insulation system of LNG storage tank. The method of claim 7,
The insulating wall formed between the liquid dome and the front wall and the side wall of the LNG storage tank further includes a space insulating material inserted into a boundary portion where the insulating box and the insulating panel face each other,
The space insulation is characterized in that having an intermediate rigidity between the insulation box and the insulation panel,
Insulation system of LNG storage tank.

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