KR20080070412A - Dummy buoy for a lng regasification vessel - Google Patents

Abstract

A dummy buoy for an LNG(Liquefied Natural Gas) re-gasification vessel is provided to have a shape equal to that of a buoy connected to a turret so as to rapidly test the operation of a newly built LNG re-gasification vessel around a built place. A dummy buoy for an LNG re-gasification vessel has the same shape and weight with a buoy practically used to be connected to a bottom of a turret of the LNG re-gasification vessel and moors to be positioned below a predetermined water level below a sea level. A dummy buoy device(30) includes a dummy buoy(31), a floating body(32), a wire rope(33), and a messenger line(35). The dummy buoy is moored at a predetermined position below the sea level by being connected to the floating body floated on the sea level through the wire rope.

Description

DUMMY BUOY FOR A LNG REGASIFICATION VESSEL}

1 is a schematic diagram schematically showing an LNG regasification system installed in an LNG regasification vessel according to the present invention;

Figure 2 is a schematic diagram schematically showing a simulation unit for LNG regasification ship according to the present invention,

3 to 9 are diagrams for explaining a method for testing the operation of the LNG regasification vessel using the simulation of the LNG regasification vessel according to the present invention.

<Description of Symbols for Major Parts of Drawings>

2: ship 3: turret

4: buoy 6: subsea terminal

10: offshore LNG regasification system 15: winch device

16: forerunner line

16a: weight 16b, 35a: small buoy

16c: hydraulic pressure release device 17: locking device

19: connector device 20: tugboat

30: simulation buoy device 31: simulation buoy

32: float 33: wire rope

35 messenger line

The present invention is to test the operation of the LNG regasification vessel equipped with an LNG regasification system for supplying natural gas in the regasified gas state to the land requirements after regasification of Liquified Natural Gas (LNG) A simulation buoy for LNG regasification ship.

In recent years, the consumption of natural gas is rapidly increasing worldwide. Natural gas is transported in a gaseous state through onshore or offshore gas piping, or to a remote consumer while stored in an LNG carrier (especially an LNG carrier) in the form of liquefied natural gas. Liquefied natural gas is obtained by cooling natural gas to cryogenic temperature (approximately -163 ℃), and its volume is reduced to about 1/600 than natural gas in gas state, so it is very suitable for long distance transportation through sea.

The LNG Carrier is designed to unload liquefied natural gas to the land requirements by loading the liquefied natural gas into the sea, and for this purpose, an LNG storage tank (commonly referred to as a 'cargo') that can withstand the cryogenic temperature of the liquefied natural gas. It includes. Normally, such LNG transport ships unload liquefied natural gas in LNG storage tanks on the land as they are liquefied, and the unloaded LNG is regasified by LNG regasification facilities installed on land, and then through gas piping to the consumer of natural gas. Is carried.

Such onshore LNG regasification facility is known to be economically advantageous when installed in a place where there is a demand for natural gas because the natural gas market is well formed. However, in the case of natural gas demand where the demand for natural gas is seasonal, short-term or periodic, it is economically disadvantageous to install LNG regasification facilities on land due to the high installation cost and management cost.

In particular, if a land LNG regasification facility is destroyed due to a natural disaster or the like, even if an LNG carrier arrives at a required destination, the LNG cannot be regasified. Holding it.

As a result, for example, an offshore LNG regasification system has been developed in which an LNG regasification facility is provided on an LNG carrier to regasify liquefied natural gas at sea and supply natural gas obtained through regasification to the land. Further, prior arts related to such offshore LNG regasification systems include Korean Patent No. 0569621 (ExxonMobil Oil Corporation, Method and System for Gasification of Liquefied Natural Gas on a Ship), and US Patent No. 6,546,739 (Exmar Offshore Company, Method and apparatus for offshore LNG regasification, US Pat. No. 6,578,366 (Moss Maritime AS, Device for evaporation of liquefied natural gas), US Pat. No. 6,688,114 (El Paso Corporation LNG CARRIER, US Pat. No. 6,598,408, El Paso Corporation, Method and apparatus for transporting LNG), Korean Patent No. 0467963 (Kang Do-wook, Al & G Alv operation method), US Patent No. 6,945,049 (Hamworthy KSE as, Regasification system and method), Korean Patent No. 0504237 (Daewoo Shipbuilding & Marine Engineering) Co., Ltd., a vessel equipped with shielding means to block the bottom opening, Korea Patent No. 0474522 (Daewoo Shipbuilding & Marine Engineering Co., Ltd. System), Korean Patent Publication No. 2003 -0090686 (Life Hoeg Unt.A.S., Ship and Unloading System), US Patent Publication No. 2005-0061002A (Shipboard regasification for LNG carriers with alternate propulsion plants), Korean Patent Publication No. 2004-0105801 (Excelate Energy Limited Partnership, Improved LNG Carrier), and Korean Utility Registration No. 0410836 (Samsung Heavy Industries Co., Ltd., Liquefied Natural Gas Regasification System).

The conventional LNG regasification vessel is equipped with a facility such as a vaporizer in the vessel for regasification of the liquefied natural gas stored in the LNG storage tank, and in addition, the piping in the system to supply the regasified natural gas to the land requirements And a connecting device for connecting the gas piping to the land requirements, and a ship position maintaining device for maintaining the position of the ship while the natural gas is unloaded.

In order to connect the pipeline of the LNG regasification vessel and the pipeline of the land, it is necessary to connect a turret, which is a structure provided in the vessel, and a buoy suspended below the sea level.

However, since the place where the LNG regasification ship is built and the place where the buoy is moored are far from each other, in order to actually check whether the newly constructed ship and the buoy are correctly connected, the newly constructed ship is constructed. There was a problem to move from the place where it was buoyed.

The present invention is to solve this problem, an object of the present invention, coupled to the turret, which is a structure provided in the LNG regasification ship to quickly test the operation of the newly built LNG regasification ship near the dry place It is to provide a simulated buoy for LNG regasification ship having the same shape as the buoy.

According to an aspect of the present invention for achieving the above object, the offshore LNG regasification system has the same shape and weight as the buoy actually used to be coupled to the bottom of the turret of the LNG regasification vessel provided, a certain depth below sea level A simulated buoy for LNG regasification vessel is provided which can be moored to be located at.

Here, the simulation buoy is preferably moored at a certain point below the sea surface by being connected to a floating body floating on the sea surface through a wire rope. In addition, it is preferable that one end of the messenger line floating on the sea surface is connected to the simulation buoy.

(Example)

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

1 shows an offshore LNG regasification system provided in an LNG regasification vessel according to an embodiment of the present invention. As shown in Fig. 1, the system 10 of the present embodiment is installed on a ship 2, and after re-gasification of the liquefied natural gas into a natural gas in a gas state with the ship 2 mooring at sea. This is supplied to the land requirements (not shown) via the subsea terminal 6.

According to the present invention, the buoy 4 moored below the sea level, which forms the distal end of the land pipe, is connected to the lower end of the turret 3 of the ship by connecting the LNG regasification system 10 and the subsea terminal 6 on the ship. It is possible to connect between and by the buoy 4 and the riser 9.

Although the system 10 of the present embodiment has been described as being installed in an LNG regasification vessel having a transport function of liquefied natural gas, the system of the present embodiment is applied to another offshore floating structure on the sea which receives liquefied natural gas from an LNG carrier and regasifies it. 10 may be installed.

The system 10 of the present embodiment includes an LNG storage tank 11, a suction drum 12 for temporarily storing liquefied natural gas drawn up from the LNG storage tank 11, and the suction drum 12. A plurality of high pressure pumps 13 (only one is shown in FIG. 1) for pressurizing the supplied liquefied natural gas to a high pressure, and the liquefied natural gas which is boosted and supplied from each of the plurality of high pressure pumps 13 to provide a heat exchange medium. And a plurality of vaporizers 14 for regasification.

As the heat exchange medium, sea water or fresh water may be used, or an intermediate heat exchange medium (eg, propane, ethane, ammonia, etc.) may be used together (see US Patent No. 6,945,049).

In order to supply the regasified natural gas to the land (that is, unloading), the gas pipes of the ship and the land pipes (especially the pipes installed on the shore wall) without using the gas pipes of the seabed or the seabed gas pipes. A method of connecting the same may be used.

In the present embodiment, the method using the subsea gas piping 7, and inter alia, the buoy 4 of the seabed is connected to the turret 3 of the ship, so that the LNG regasification system 10 and the subsea terminal 6 on the ship are connected. The Submerged Turret Loading (STL) method, which is a method of connecting between the buoy 4 and the riser 9, is used. However, this STL scheme may be modified in various forms and is not intended to limit the present invention.

2 shows a schematic diagram of a simulated buoy device 30 for testing the operation of an LNG regasification vessel according to the invention. As shown in FIG. 2, the simulated buoy device 30 for LNG regasification ship according to a preferred embodiment of the present invention includes a simulated buoy 31 having the same shape and weight as a buoy actually used, and the simulated buoy ( 31 is connected via a wire rope 33 and comprises a float 32 for mooring the simulated buoy 31 to a certain depth below sea level.

As the floating body 32, any one can be used as long as it can stably mow the simulated buoy 31 such as one or more small ships or balloons. However, in the present embodiment, the floating body 32 is located between the ship under construction and the wharf. It uses an air fender that acts as a shock absorber. Air fenders can be easily obtained at the ship construction site, it is preferable because it can stably support the weight of the simulated buoy 31 of about 20 to 30 tons.

As the air fender, a steel material coated with a rubber material for shock absorption may be used. In addition, the outer periphery of the air fender may be mounted with a reinforcing structure (not shown) made of waste tires and the like.

The length of the wire rope 33 connecting between the float 32 and the simulated buoy 31 is determined such that the simulated buoy 31 can be located approximately 40 meters below the water surface.

The simulation buoy device 30 may further include a messenger line 35 connected to the simulation buoy 31. One or more small buoys 35a having a predetermined buoyancy are attached to the messenger line 35 so that one end of the messenger line 35 is connected to the simulated buoy 31 while the other end floats on the sea surface. It is.

Similar to the buoy actually used, the simulation buoy 31 transmits a signal to a buoy position detection device (not shown) mounted on the vessel 2 and receives a plurality of transponder sensors 31a informing the buoy's position. Have These plurality of transponder sensors 31a are preferably arranged at equal intervals along the outer circumference of the lower frame of the simulation buoy 31.

Hereinafter, the operation test method of the LNG regasification vessel using the simulation buoy device according to a preferred embodiment of the present invention made as described above with reference to Figs.

First, FIG. 2 shows a state in which the simulated buoy 31 is moored at about 50 meters in depth. As described above, the simulation buoy 31 is moored about 40 meters from the sea surface by the floating body 32 via the wire rope 33, and the messenger line 35 having one end connected to the simulation buoy 31. The other end of) is floated on the sea surface by the small buoy 35a.

In order to arrange each component of the simulation buoy device 30 as shown in FIG. 2, each of these components is loaded on a tugboat 20, etc., and transported to a position suitable for an experiment, and then a marine crane (not shown) installed in a tugboat or the like. It is preferred to be disposed at sea by).

On the other hand, in the LNG regasification vessel 2, in order to connect the messenger line 35 of the mock buoy device 30 with the forerunner line 16 of the vessel 2, first shown in FIG. 3. As such, a weight 16a, such as a sandbag, and one or more small buoys 16b are suspended at the end of the forerunner line 16 through the turret 3 of the LNG regasification vessel 2.

The forerunner line 16 can be lowered or raised into the seawater by being wound or unwound by the winch device 15 installed on the LNG regasification vessel 2. The weight 16a is connected to a distal end of the forerunner line 16 via a hydraulic pressure releaser 16c.

As shown in FIG. 4, since the weight 16a, such as a sandbag, is suspended at the end of the forerunner line 16, when the winch device 15 is released, the forerunner line 16 is the turret 3 of the ship. Can be sent down to the sea.

At this time, the hydraulic pressure release device 16c interposed between the end of the forerunner line 16 and the weight body 16a separates the connected weight body 16a when the water pressure reaches a predetermined depth and rises above the set value. When the weight body 16a is separated, the end portion of the forerunner line 16 floats to the sea level due to the buoyancy force of the small buoy 16b attached to the forerunner line 16.

The forerunner line 16 floated to the sea level is lifted up by the worker on the deck of the ship 2 using the hook 21 or the like. It is desirable to move the vessel 2 slightly to the left or to the right when descending the forerunner line 16 so that the forerunner line 16 floats toward the left and right sides of the vessel 2 as it rises to sea level.

Subsequently, the worker lifts the messenger line 35 of the simulation buoy device 30 onto the deck of the ship 2 using the hook 21 or the like as shown in FIG. 5, and as shown in FIG. 6. The forerunner line 16 and the messenger line 35, which are raised on the deck of the ship 2, are connected to each other.

Thus, by connecting the messenger line 35 of the mock buoy device 30 to the forerunner line 16 wound around the winch device 15 of the ship 2, the winch device 15 as shown in FIG. By using the forerunner line 16 is wound around the mock buoy 31 connected to the messenger line 35 can be pulled up.

At this time, the wire rope 33 is connected between the floating body 32 in order to moor the simulation buoy 31, the simulation buoy 31 is shown in the bottom of the turret 3 of the ship as shown in FIG. It is preferred to be separated by divers before being combined.

The winch device 15, which was stationary while disconnecting the wire rope 33, was reactivated after the wire rope 33 was removed so that the simulated buoy 31 is fully engaged with the bottom of the turret 3 of the ship ( The simulated buoy 31 is pulled up to a dotted line in FIG. 8).

When the simulation buoy 31 is coupled to the bottom of the turret 3, the winch device 15 is stopped, and the simulation buoy 31 is provided by the locking device 17 provided in the turret 3 as shown in FIG. While holding and fixing the upper outer periphery of the connection of the connector device 19 to the top of the simulation buoy (31).

The connector device 19 is a device for supplying natural gas regasified by the LNG regasification system 10 provided in the ship 2 to the buoy side.

After the simulation buoy 31 is coupled, the regasification system 10 mounted on the LNG regasification vessel 2 assuming that the buoy is coupled to the turret 3 of the LNG regasification vessel 2 in the actual situation. You may check the operation abnormality, etc.

As described above, the new buried LNG regasification vessel is tested by testing the process in which the simulation buoy 31 is coupled to and fixed by the turret 3 of the LNG regasification vessel 2 using the simulation buoy device 30. You can check the operation of (2).

The process of separating the mock buoy 31 coupled to the bottom of the turret 3 is fixed as follows.

First, while releasing the locking device 17 holding the upper outer circumference of the simulation buoy 31, the connector device 19 connected to the upper end of the simulation buoy 31 is detached, and then the winch device 15 is operated. When the forerunner line 16 and the messenger line 35 which have been wound are released, the simulation buoy 31 is separated from the lower end of the turret 3 by its own weight and descends into the sea.

Immediately after the simulation buoy 31 is separated from the bottom of the turret 3 of the ship, the winch device 15 is stopped for a while, and the wire rope 33 connected to the floating body 32 by the diver is simulated by the buoy 31. To.

When the wire rope 33 is connected to the simulated buoy 31, the stopped winch device 15 is operated again to lower the simulated buoy 31 to the depth at which the simulated buoy 31 is moored by the float 32. After that, the messenger line 35 and the forerunner line 16 are separated from each other to completely separate between the simulation buoy device 30 and the LNG regasification vessel 2.

Each component of the simulated buoy device 30 separated from the ship 2 may be returned to the pier on a tugboat 20, which was waiting nearby.

On the other hand, before the simulation buoy device 30 is completely separated from the vessel 2, the vessel is removed by carrying out the separation process of the simulation buoy 31 in various ways such as normal normal separation operation, manual separation operation and emergency separation operation in case of emergency. It is preferable to perform a situational separation test between the turret 3 and the simulation buoy 31 in (2).

While the invention has been described above with reference to specific embodiments, various modifications, changes or modifications may be made in the art within the spirit of the invention and the appended claims, and thus the foregoing description and drawings illustrate It should be construed as illustrating the present invention, not limiting the technical spirit of the invention.

According to the present invention as described above, the LNG having the same shape as the buoys coupled to the turret which is a structure provided in the LNG regasification ship, so that the operation of the newly constructed LNG regasification ship can be quickly tested near the dried place. A simulated buoy for regasification vessels is provided.

According to the present invention, without the need to move the LNG regasification vessel to the place where the actual buoy is installed, using the simulated buoy to perform the normal operation check test of all equipment under the same conditions as the buoy coupling operation actually performed during ship operation do.

By testing all the equipment installed on the LNG regasification ship under the same conditions as the actual operating conditions, all problems that may occur after the ship is delivered can be detected in advance, so that the reliability and post-delivery reliability can be improved. Maintenance costs such as management costs can be reduced.

Claims (7)

LNG regasification, characterized in that the marine LNG regasification system has the same shape and weight as the buoy actually used to be coupled to the bottom of the turret of the LNG regasification vessel provided, and can be located at a certain depth below the sea surface Marine mock buoys. The method according to claim 1, The simulated buoy is buried for LNG regasification ship, characterized in that it is moored at a certain point below the sea surface by being connected to a floating body floating on the sea surface through a wire rope. The method according to claim 2, The floating body mock buoy for LNG regasification ship, characterized in that for using the air fender positioned between the ship and the pier in the ship construction site to perform a buffer role. The method according to claim 1, The simulated buoy for LNG regasification vessel, characterized in that one end of the messenger line floating on the sea surface is connected. The method according to claim 4, One or more small buoys with buoyancy are attached to the messenger line so that one end of the messenger line is connected to the simulated buoy while the other end is floated on the sea surface. The method according to claim 1, The simulated buoy has a plurality of transponder sensors that communicate a signal with a buoy position detection device mounted on the LNG regasification vessel and inform the position of the buoy, wherein the plurality of transponder sensors are provided in the lower frame of the simulated buoy. A simulated buoy for LNG regasification ship, characterized in that it is arranged at equal intervals along the outer periphery. A simulation buoy for testing the operation of an LNG regasification vessel equipped with an offshore LNG regasification system, Simulated buoys having the same shape and weight as buoys actually used; A float connected to the mock buoy via a wire rope to moor the mock buoy to a predetermined depth below sea level; And A messenger line, one end of which is connected to the simulated buoy while the other end is suspended on the sea surface; Simulated buoy device, characterized in that consisting of.

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