KR20170045923A

KR20170045923A - LNG Carrier

Info

Publication number: KR20170045923A
Application number: KR1020150146024A
Authority: KR
Inventors: 이동대; 최익흥; 이병록; 김형관; 최병기; 류홍렬; 이정훈; 손익휘; 오훈규; 성정환; 김두현; 전민호
Original assignee: 현대중공업 주식회사
Priority date: 2015-10-20
Filing date: 2015-10-20
Publication date: 2017-04-28
Also published as: KR102017929B1

Abstract

The present invention relates to an LNG carrier, comprising: a front storage tank having a length of 13% or more of a distance between perpendicular lines, and spaced apart from a forward perpendicular line; a rear storage tank having a length within 17% of the distance between the perpendicular lines, and spaced apart from an after-perpendicular line; and an intermediate storage tank having a length within 17% of the distance between the perpendicular lines, and installed between the front storage tank and the rear storage tank.

Description

LNG Carrier {LNG Carrier}

The present invention relates to an LNG carrier.

In recent years, liquefied gas such as Liquefied Natural Gas (LNG), Liquefied Petroleum Gas (LPG) and the like has been widely used as a substitute for gasoline or diesel.

Liquefied natural gas is a liquefied natural gas obtained by refining natural gas collected from a gas field. It is a colorless and transparent liquid with almost no pollutants and high calorific value. It is an excellent fuel. On the other hand, liquefied petroleum gas is a liquid fuel made from compressed propane (C ₃ H ₈ ) and butane (C ₄ H ₁₀ ), which are derived from petroleum in oil field, at room temperature. Liquefied petroleum gas, like liquefied natural gas, is colorless and odorless and is widely used as fuel for household, business, industrial, and automotive use.

Such a liquefied gas is stored in a liquefied gas storage tank installed on the ground or stored in a liquefied gas storage tank provided in a transportation means navigating the ocean. Liquefied natural gas is reduced to 1/600 volume by liquefaction, Liquefied petroleum gas has the advantage of liquefaction, which reduces the volume of propane to 1/260 and the volume of butane to 1/230, which is high storage efficiency.

For example, liquefied natural gas (LNG) is obtained by cooling natural gas at a cryogenic temperature (approximately -163 ° C), and its volume is reduced to approximately 1/600 of that of natural gas, .

LNG carriers for loading LNG and landing on the sea to the sea include LNG cryogenic storage tanks (so-called 'cargo holds').

Such a storage tank can be classified into an independent type and a membrane type according to whether or not the load of the cargo directly acts on the insulating material. Normally, the membrane type storage tank is classified into NO 96 type and Mark III Type storage tanks are divided into MOSS type and SPB type.

LNG carriers from 60K to 180K are equipped with four storage tanks. Among the four storage tanks, the storage tanks installed on the fore part are relatively small due to the influence of sloshing. For example, the length of one forward tank is limited to 13% of the Length Between Perpendiculars (LBP), and the two intermediate storage tanks (central tank) and one rear storage tank ) Each length is limited to 17% of the length of the waterline. The forward storage tanks are constructed so that the width of the storage tanks is also narrow due to the characteristics of the streamlined vessels so that about half of the capacity of each of the remaining three storage tanks can be loaded.

These LNG carriers have different operating losses within the transportation period depending on the BOR (Boil Off Rate) scale.

However, since existing LNG carriers have four storage tanks, there is a limit to reduce the BOR (Boil Off Rate) proportional to the surface area of the storage tank. For example, by applying ME-GI engine and PRS technology, BOR can be reduced from 0.05% to 0.06% compared with the existing system, or BOR can be reduced by 0.08% by applying Ti Group's new storage tank insulation system. Various studies have been conducted to reduce the amount of BOR, but the degree of BOR reduction is low.

Published Japanese Patent Application No. 10-2014-0100454 (Published on August 14, 2014) Published Japanese Patent Application No. 10-2015-0027781 (Published on March 12, 2015)

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems of the prior art, and it is an object of the present invention to reduce the number of storage tanks without changing the ship size and LNG loading capacity in comparison with existing LNG carriers, To reduce the BOR, thereby providing an LNG carrier.

It is also an object of the present invention to provide an LNG carrier which can reduce the manufacturing cost of a storage tank by reducing the number of storage tanks in comparison with existing LNG carriers.

It is another object of the present invention to provide an LNG carrier which can increase the space utilization of the fore and aft parts by increasing the stacking capacity by increasing the line width and height while reducing the number of storage tanks in comparison with existing LNG carriers. will be.

In addition, the object of the present invention is to reduce the sloshing phenomenon and increase the length of the front tank by more than 13%, preferably by 15 to 16%, by arranging the forward storage tank installed on the side of the fore part far from the bow, And to reduce the volume-to-volume surface area of the LNG carrier to ultimately reduce the BOR.

It is also an object of the present invention to provide an LNG carrier which is capable of moving a bridge and a residence in an extended space of a bow, securing a forward view, and diversifying design specifications of the ship.

The LNG carrier according to one aspect of the present invention comprises: a front storage tank having a length of 13% or more of the length between the waterlines and spaced apart from the forward waterline; A rear storage tank having a length of less than 17% of the length of the waterline and spaced a distance from the aft waterline; And an intermediate storage tank installed between the forward storage tank and the rear storage tank, the length of which is within 17% of the length between the waterlines.

Specifically, the LNG can be loaded into three storage tanks including the front storage tank, the rear storage tank, and the intermediate storage tank.

Specifically, the forward storage tanks are constructed to be capable of loading 20% to 30% of the total loading capacity, and the intermediate and rear storage tanks are each loaded with 35% to 40% of the total loading capacity It can be made in a size that can be made.

Specifically, the forward storage tank may be arranged such that the shear inner wall starts at a position spaced from 18% to 25% of the inter-repudiation length from the forward waterline.

Specifically, a residence and a bridge may be installed at the bow.

Specifically, each of the front storage tank, the intermediate storage tank, and the rear storage tank may be an SPB type.

Specifically, each of the front storage tank, the intermediate storage tank, and the rear storage tank may have a polygonal shape.

Specifically, the LNG carriers may be more than 60K class.

The LNG carrier according to the present invention can reduce the total surface area of the storage tank by reducing the number of storage tanks without significantly changing the ship size and LNG loading capacity in comparison with the existing LNG carriers, , The manufacturing cost of the storage tank can be reduced.

In addition, the LNG carrier according to the present invention increases the space utilization of the fore and aft parts by increasing the storage capacity by increasing the line width and increasing the height by maintaining the same amount of drainage while reducing the number of storage tanks in comparison with the existing LNG carriers. .

In addition, the LNG carrier according to the present invention can reduce the sloshing phenomenon by increasing the length of the storage tank by increasing the storage amount of the tank at the front, The BOR can be reduced.

Further, the LNG carrier according to the present invention can move the bridge and the residence to the extended space of the forward portion, thereby securing the forward view and diversifying the design specifications of the ship.

1 is a side view for explaining an LNG carrier according to an embodiment of the present invention.
2 is a cross-sectional view taken along the line A-A 'in FIG.
3 is a plan view illustrating an LNG carrier according to an embodiment of the present invention.
FIG. 4 is a view showing a state where a bridge and a residence of an LNG carrier according to an embodiment of the present invention are moved and arranged in an empty space of a bow.

BRIEF DESCRIPTION OF THE DRAWINGS The objects, particular advantages and novel features of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. It should be noted that, in the present specification, the reference numerals are added to the constituent elements of the drawings, and the same constituent elements are assigned the same number as much as possible even if they are displayed on different drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a side view for explaining an LNG carrier according to an embodiment of the present invention. FIG. 2 is a sectional view taken along line A-A 'of FIG. 1, FIG. 4 is a view showing a state where a bridge and a residence of an LNG carrier according to an embodiment of the present invention are moved and arranged in an empty space of a bow. FIG.

1 to 3, the LNG carrier 100 according to an embodiment of the present invention includes a storage tank 110, a ballast tank 120, a habitat 130, a bridge 140, And the like.

In this embodiment, the LNG carrier 100 can be a ship that has no change in ship size and LNG loading capacity in comparison with existing LNG carriers (not shown) of 60K to 180K classes in which four storage tanks are installed However, the line width can be increased to secure stability, and the amount of drainage is maintained at the same level by decreasing the squareness coefficient Cb.

The storage tank unit 110 may be provided in the hull 101 so as to store the LNG.

The storage tank unit 110 may include a front storage tank 111, an intermediate storage tank 112 and a rear storage tank 113 when the LNG carrier 100 is in the range of 60K to 180K. Each of the storage tanks 111, 112, and 113 may be a membrane type, NO 96 type, Mark III type, stand alone type, SPB type, or polygonal or various types of tanks.

The front storage tank 111 of the present invention is formed so that its length is 13% or more, preferably 15% or more of the inter-reproductive length (LBP), which is the horizontal distance between the fore and aft perpendicular (FP) To 18%, preferably 18%, more preferably 18% to 16%, more preferably 15% of the interline length (LBP) from the forehead line (FP) To 25%, and more preferably 20%, of the total LNG loading capacity, and may be manufactured to a size capable of loading 20% to 30% of the total LNG loading capacity.

In the embodiment of the present invention, the forward storage tank 111 is configured to be spaced 18% to 25% of the inter-repaired length LBP from the forward water repellent FP, By limiting the forward storage tank 111 to be located within 15% of the length LBP, it is possible to prevent the forward slip of the forward storage tank 111 from being generated in the front storage tank 111 due to the pitching motion of the hull, The point where the acceleration of the liquefied gas is high, that is, the point where the resonance occurs) can be avoided.

The intermediate storage tank 112 and the rear storage tank 113 are limited in length to within 17% of the inter-reprocessing length LBP and can be sequentially installed behind the forward storage tank 111, 35% to 40%.

The middle and rear storage tanks 112 and 113 are located in the middle of the hull and are less affected by the pitching motion of the hull than the forward storage tanks 111. However, when the longitudinal storage tanks 112 and 113 are 17% or more of the waterline length (LBP) So that the durability of the intermediate and rear storage tanks 112 and 113 is weakened, and there is a fear that the durability of the middle and rear storage tanks 112 and 113 may be destroyed.

Therefore, in the embodiment of the present invention, the lengths of the intermediate storage tank 112 and the rear storage tank 113 are limited to within 17% of the waterline length LBP, so that the middle and rear storage tanks 112, The BOR of the forward storage tank can be effectively reduced by reducing the surface area at which the liquefied gas is exposed.

Upper sections of the storage tanks 111, 112 and 113 are positioned between 70% of the height of the storage tanks 111, 112 and 113 and 98% of the volume of the storage tanks 111, 112 and 113, May be positioned between 10% of the volume of each of the storage tanks 111, 112, 113 from the bottom of each of the storage tanks 111, 112, 113.

As described above, in the embodiment of the present invention, in order to reduce the BOR, the cross section where the upper water level of each of the storage tanks 111, 112, and 113 is located may be gradually decreased. The length of the forward storage tank 111 may be defined as the inter- The length of the intermediate storage tank 112 and the rear storage tank 113 is limited to within 17% of the length LBP of the water lines so that the surface area of the liquefied gas can be minimized to the outside .

The three storage tanks 111, 112 and 113 of the LNG carrier 100 of the present embodiment are limited to 45% to 50% of the inter-line length LBP to achieve the LNG full loading capacity of 100% On the other hand, in the conventional LNG carriers, the four storage tanks can be constructed with more than 60% of the total length of the waterline, achieving a total loading capacity of 100% of the LNG. Accordingly, each of the three storage tanks 111, 112, and 113 according to the present embodiment is increased in size compared to each of the four storage tanks, but the number of the storage tanks 111, 112, and 113 is reduced, Thus, the BOR proportional to the surface area can be reduced.

For example, when the LNG carrier 100 is 180K class, the three storage tanks 111, 112, and 113 of the present embodiment manufactured to the above-described size can have a total surface area of about 26,000 m 2, The existing four storage tanks have an overall surface area of about 29,000 square meters. Accordingly, it can be seen that the total surface area of the present embodiment is reduced to about 90% of the existing surface area. This is because the LNG carrier 100 of the present embodiment can reduce the BOR by about 10% .

The three storage tanks 111, 112 and 113 of the LNG carrier 100 of the present embodiment are configured such that the overall length is limited to within 50% of the inter-line length LBP, The overall length may correspond to more than 50% of the inter-reproductive length (LBP). On the other hand, in a conventional LNG carrier, the total length of four storage tanks is more than 60% of the length of the waterline, so that the total length of the bow and stern can be less than 40% of the waterline length. That is, it can be seen that the space utilization of the bow 102 and stern 103 is increased in comparison with the conventional LNG carrier in the LNG carrier 100 of the present embodiment.

Accordingly, the front storage tank 111 of the present embodiment is arranged such that the inner wall of the front end is started at a position spaced from 18% to 25% (preferably 20%) of the inter-repellent length LBP from the forehead water line FP . That is, the LNG carrier 100 according to the present invention can reduce the sloshing phenomenon and reduce the BOR by arranging the front storage tank 111 provided on the side of the bow 102 as far as possible from the forehead waterline FP do.

The ballast tank 120 is a water tank for storing the ballast water that can be stably sailed by increasing the weight of the LNG carrier line 100. The water tank includes a front storage tank 111, an intermediate storage tank 112, a rear storage tank 113, respectively, that is, on the side and bottom of the hull 101, thereby increasing the ballast draft and enhancing the terminal compatibility with the LNG terminal.

Since the ballast tanks 120 are installed on the side and bottom of the three storage tanks 111, 112 and 113, they can be reduced in number compared to the number of the storage tanks installed on the side and bottom of the four storage tanks of the conventional LNG carrier, Ballast tank installation can be saved.

The residence 130 may be provided to enable crews to live and reside there, and a bridge 140 to be described later may be installed at an upper portion thereof.

The bridge 140 is a ship operation control center having various equipment and facilities necessary for operating the LNG carrier 100. The bridge 140 is located at the uppermost part of the hull structure, for example, at the upper part of the habitat 130, Radar, and communication device.

In order to increase the space utilization of the LNG carrier 100, the residence 130 and the bridge 140 may be used as the residence 130 and the bridge 140 may be used as the bridge 130. However, Of course, be installed.

The inhabiting port 130 and the bridge 140 can be installed at the center, aft portion or bow portion of the hull according to the ship. In the case of the LNG carrier 100, the outlook is not good, but the amount of load The stern section 103 is provided.

However, in this embodiment, as shown in FIG. 4, the residence section 130 and the bridge 140 can be installed on the bow portion 102. This is because, unlike the existing LNG carriers, the LNG Three storage tanks 111, 112 and 113 are provided in the carrier 100 and the front storage tank 111 is positioned at a position spaced from 18% to 25% of the waterline length LBP from the forehead water line FP The inner wall of the front end can be arranged so that the space of the forward portion 102 can be sufficiently secured.

The residence port 130 and the bridge 140 installed in the bow portion 102 may be uncomfortable because the amount of up-and-down movement is large when the bridge is installed too far, so that the residence port 130 and the bridge 140 installed close to the front end wall of the forward storage tank 111, May be desirable.

As a result, the present embodiment allows the residence section 130 and the bridge 140 to be installed on the bow portion 102, thereby securing a forward view and diversifying the design specifications of the ship. The bridge 140 is installed at a position higher than the upper portion of the residence 130 when there is a structure obstructing the view in front. It is possible to install the bridge 140 directly on the upper portion of the residence 130, thereby reducing the number of bridges 140 installed.

The present embodiment reduces the number of the storage tanks 111, 112 and 113 without changing the ship size and the LNG overall loading capacity in comparison with the conventional LNG carriers, The total surface area can be reduced, BOR can be reduced, and the manufacturing cost of the storage tanks 111, 112, and 113 can be reduced.

In this embodiment, the number of the storage tanks 111, 112 and 113 is reduced, the same amount of drainage is maintained, the line width is slightly increased and the height is increased to increase the stacking capacity in comparison with the existing LNG carriers. And the space utilization of the stern section 103 can be increased.

Further, in the present embodiment, by disposing the forward storage tank 111 provided on the side of the bow portion 102 away from the bow portion 102, not only the sloshing phenomenon is reduced but also the length of the storage tank is increased, And the BOR can be reduced by reducing the surface area relative to the volume.

In addition, in the present embodiment, the bridge 140 and the residence 130 can be moved and arranged in the extended space of the bow 102, thereby securing the forward view and diversifying the design specifications of the ship.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be apparent to those skilled in the art that various combinations and modifications may be made without departing from the scope of the present invention. Therefore, it should be understood that the technical contents related to the modifications and applications that can be easily derived from the embodiments of the present invention are included in the present invention.

100: LNG carrier 101: Hull
102: bow 103: stern
110: Storage tank part 111: Front storage tank
112: intermediate storage tank 113: rear storage tank
120: Ballast tank 130: Residential area
140: Bridge
LBP: Inter-track length FP: Player repair
AP: Stern repair

Claims

A forward storage tank having a length of 13% or more of the length of the waterline and spaced apart from the forward waterline;
A rear storage tank having a length of less than 17% of the length of the waterline and spaced a distance from the aft waterline; And
And an intermediate storage tank disposed between the forward storage tank and the rear storage tank, the length of which is within 17% of the inter-rupture length.

The method according to claim 1,
Wherein the LNG carrier is loaded in three storage tanks comprising the forward storage tank, the rear storage tank and the intermediate storage tank.

3. The method of claim 2,
The forward storage tank is manufactured to have a size capable of loading 20% to 30% of the total loading capacity,
Wherein the rear and intermediate storage tanks are constructed to a size capable of loading between 35% and 40% of the total loading capacity.

2. The fuel cell system according to claim 1,
Characterized in that the shear inner wall is arranged at a position spaced from 18% to 25% of the inter-repudiation length from the forward perpendicular.

The method according to claim 1,
Characterized in that a residence section and a bridge are installed in the forward section.

2. The water treatment system according to claim 1, wherein each of the forward storage tank, the intermediate storage tank,
LNG carrier.

2. The water treatment system according to claim 1, wherein each of the forward storage tank, the intermediate storage tank,
Wherein the LNG carrier is formed in a polygonal shape.

The method according to claim 1,
LNG carriers characterized in that they are at least 60K class.