WO2009068768A1

WO2009068768A1 - Apparatus for transferring a fluid between a first ship and a second ship floating on an expanse of water, and related transport assembly and method

Info

Publication number: WO2009068768A1
Application number: PCT/FR2008/051978
Authority: WO
Inventors: Paul Risi; Virginie Lehning
Original assignee: Technip France
Priority date: 2007-11-14
Filing date: 2008-11-03
Publication date: 2009-06-04
Also published as: FR2923453A1; BRPI0820291A2; FR2923453B1

Abstract

The invention relates to an apparatus (10) that comprises a first rigid duct (80A), an upstream hose (82A) hydraulically connected to the rigid duct (80A) and to the first ship (18), and a downstream hose (84A) hydraulically connected to the rigid duct (80A) and to the second ship (20). The apparatus includes a carrier structure (60) floating on the water surface and provided between the first ship (18) and the second ship (20). The rigid duct (80A), the upstream hose (82A) and the downstream hose (84A) are mounted on the carrier structure (62). It comprises a means (66A) for attaching a mooring line (32) of the first ship, provided along a mooring surface (74A) of the carrier structure located opposite the first ship (18), and a means (66B) for attaching a mooring line (50) of the second ship, provided along a mooring surface (74B) of the carrier structure located opposite the second ship (20).

Description

A fluid transfer facility between a first vessel and a second vessel floating on a body of water, a transport assembly and associated method.

The present invention relates to a fluid transfer installation between a first vessel and a second vessel floating on a body of water, of the type comprising a hydraulic transfer distributor comprising:

at least one first rigid fluid transfer pipe; and for the or each rigid pipe:

at least one upstream fluid transfer hose connected hydraulically to the rigid transfer line and intended to be connected to the first vessel;

at least one downstream fluid transport hose, hydraulically connected to the rigid transfer line and intended to be connected to the second vessel.

The present invention is particularly applicable to the transfer of liquid hydrocarbons such as liquefied gases such as liquefied natural gas (LNG) or liquefied petroleum gas (LPG). This transfer is made between a first ship and a second ship floating on a body of water, such as a sea or an ocean.

The first vessel is for example a production vessel, liquefaction, storage and discharge of liquefied hydrocarbons (designated in English by "Floating Production Storage and Offloading Ship" or "FPSO"). These FPSOs are placed in the vicinity of a hydrocarbon production site at sea.

The second vessel is, for example, a floating liquefied natural gas (LNG-Carrier or LNG-C) transport vessel for conveying liquefied hydrocarbon from its production site to a site of use. . In another example, the first vessel is a LNG-C and the second vessel is a floating storage and regasification unit (referred to as Floating Storage and Regas Unit or FSRU) for storing and converting a vessel. hydrocarbon liquified into a gas for supply to a land installation. Given certain safety and ship movement constraints, it is preferable to carry out fluid transfer operations between vessels by keeping them out of a harbor, in shallow waters, by example a few hundred meters from the coast. It is sometimes necessary to carry out these operations in deep water.

To carry out such operations, GB 2 367 049 discloses a transfer installation of the aforementioned type. This installation includes a hydraulic distributor that includes a pair of rigid fluid transfer lines, and connection hoses for connecting each transfer line to the one and the other of the vessels between which the transfer of fluids is to be made. .

The hydraulic distributor is stored at rest on the hull of one of the vessels, which has the disadvantage of requiring a large space for storage on one of the vessels, taking into account the dimensions required for such a system ( about 70m). The overall cost of the equipped boat is therefore high.

To use the transfer facility, the two ships are placed in the vicinity of each other, maintaining a large free space between them. Wire ropes are stretched between the two ships, then the hydraulic distributor is moved over the cables, to be held in suspension on the cables in the free space between the ships. The connection hoses are then connected to both vessels to perform the fluid transfer.

Such a device does not give complete satisfaction. It is difficult to carry out an emergency disconnection with the system proposed in GB 2 367 049 because such disconnection requires repositioning on one of the vessels the transfer assembly formed by the cable and the transfer line.

In addition, the cables stretched between the two vessels must be kept under very high tension to support the weight of the suspended rigid pipes, taking into account the pipe diameters required to ensure a transfer flow rate of, for example, 10 000 m ^3. / h and 14,000 m ³ / h.

In addition, given the large safety distance that must be maintained between ships, the force of gravity due to the weight of the hydraulic distributor causes a downward deformation of the cables which increases with the safety distance. This makes the system sensitive enough to the relative accelerations induced between the ships by the waves or the swell, with a risk of damage for one of the boats. In addition, the configuration of the hoses during transfer is not controlled, so that they may be subject to curvatures that may deteriorate or reduce their life in the event of a high flow.

An object of the invention is therefore to obtain a fluid transfer facility, including liquefied hydrocarbon, between two vessels, which can be used safely, especially in water bodies with little or no protection.

For this purpose, the subject of the invention is a transfer installation of the aforementioned type, characterized in that it comprises:

a buoyant structure floating on the body of water, intended to be interposed between the first vessel and the second vessel, the first rigid pipe, the upstream pipe, and the downstream pipe being mounted on the bearing structure;

at least one first means for attaching a first mooring line of the first ship to the carrying structure disposed along a first mooring surface of the carrying structure, the first mooring surface being adapted to be placed next to the first ship;

at least one second means for attaching a second mooring line of the second vessel disposed along a second mooring surface of the carrying structure, the second mooring surface being suitable for being placed opposite the second mooring line of the second ship.

The installation according to the invention may comprise one or more of the following characteristics, taken separately or according to any combination (s) technically possible (s):

it comprises at least one handling unit carried by the carrier structure, the or each handling assembly being able to move the upstream hose and the downstream hose between a rest position in which said hoses are retracted towards the supporting structure and an active fluid transfer position in which said hoses are connected respectively to the first vessel and the second vessel; the upstream hose and the downstream hose are hanged in a chain on the or each handling assembly in the rest position and in the active position; - The first mooring surface and the second mooring surface are substantially parallel and opposite to each other;

the first mooring surface and the second mooring surface are substantially perpendicular to one another; and - the hydraulic distributor comprises:

a second rigid transfer pipe mounted parallel to the first rigid pipe for transferring fluid onto the supporting structure, and

at least one branch connecting the first rigid pipe to the second rigid pipe, the bypass being provided with at least one hydraulic valve operable between a first configuration in which the first rigid pipe and the second rigid pipe are hydraulically connected and a second configuration in which the first rigid pipe is hydraulically isolated from the second rigid pipe.

The invention further relates to a fluid transport assembly, characterized in that it comprises:

a transfer installation as defined above;

a first vessel placed opposite the first mooring surface and connected to the first attachment means by at least one first mooring line, the upstream hose being hydraulically connected to the first vessel; - A second vessel placed opposite the second mooring surface and connected to the second fastening means by at least a second mooring line, the downstream hose being hydraulically connected to the second vessel. The assembly according to the invention may comprise one or more of the following characteristics, taken in isolation or according to any combination (s) technically possible (s):

- An axial end of the first ship extends opposite the first mooring surface, an axial end of the second vessel extending opposite the second mooring surface, the first and second vessels thus being placed axially end to end of both sides of the supporting structure; the second vessel comprises a lateral surface, the lateral surface of the second vessel being placed facing the second mooring surface parallel to an axis of the carrying structure; and the first mooring surface and the second mooring surface are perpendicular to each other, the axial end of the first vessel being placed facing the first mooring surface, the lateral surface of the second mooring surface and the second mooring surface are perpendicular to each other, the lateral surface of the second vessel being attached to the second mooring surface. The subject of the invention is also a method for transferring fluid, in a transport assembly as defined above, characterized in that it comprises the following steps:

placing the first vessel next to the first mooring surface of the load-bearing structure and placing the second vessel opposite the second mooring surface of the load-bearing structure;

- Implementation of the or each first line of mooring between the first vessel and the first attachment means, and implementation of the or each second line of mooring between the second attachment means and the second vessel, - hydraulic connection of the upstream hose to the first vessel and hydraulic connection of the downstream hose to the second vessel;

- Transfer of fluid between the first vessel and the second vessel through successively the upstream hose, the first rigid pipe and the downstream hose.

The invention will be better understood on reading the description which follows, given solely by way of example, and with reference to the appended drawings, in which:

- Figure 1 is a side view of a first transport assembly according to the invention comprising a transfer facility between a first vessel and a second vessel; - Figure 2 is a top view of the assembly of Figure 1;

3 is a view of a marked detail III in FIG. 2, illustrating in particular the hydraulic distributor of the transfer installation of FIG. 2;

- Figure 4 is a side view of a second transport assembly according to the invention; and - Figure 5 is a top view of the transport assembly of the figure

4.

Figures 1 to 3 illustrate a first transport assembly 10 according to the invention, floating on a body of water 12. This assembly 10 applies to the transport and transfer of liquefied hydrocarbons, in particular liquefied natural gas (LNG), liquefied petroleum gas (LPG) or any other type of liquefied gas. These liquefied hydrocarbons are generally cryogenic liquids having a temperature much lower than the ambient temperature.

The body of water 12 is an expanse of salt water such as a sea or an ocean, or an expanse of fresh water such as a lake. The expanse of water 12 rests on a solid bottom 14.

The depth of the water 12 between the bottom 14 and the surface 16 around the transport assembly 10 is for example between 15 meters and 900 meters, although greater depths, including up to 3000 meters or more can be considered.

In this example, the floating assembly 10 comprises, from left to right in FIG. 1, a first liquefied hydrocarbon production and storage vessel 18, a second liquefied hydrocarbon transport vessel 20, and a transfer facility. 22 floating, interposed between the ships 18, 20 to transfer fluid between these vessels.

In all that follows, it will be readily understood that the transport assembly 10 is entirely reversible, that is to say that the transfer facility 22 can be used to transfer a fluid present in the first vessel 18 to the second vessel 20, or conversely transfer a fluid present in the second vessel 20 to the first vessel 18. Only the first case will be described in all that follows.

The first vessel 18 is for example a production vessel, liquefaction, storage and discharge of liquefied hydrocarbons (designated in English by "Floating Production Storage and Offloading Ship" or "FPSO"), placed in the vicinity of a production site. hydrocarbons on the high seas.

With reference to FIG. 1, the first vessel 18 comprises a floating hull 24 having a trailing edge 26 transverse to an axis of the hull 24, means 28 for liquefying a gaseous hydrocarbon to transform it into a liquefied hydrocarbon. and at least one liquefied hydrocarbon storage tank. The shell 24 is anchored in the bottom 14 of the body of water 12 via an anchor line 31. As a variant, the shell 24 is anchored by means of a drum (designated by the English term "turret") as described in WO87 / 05876. The ship 18 further comprises, along its rear edge 26, at least a first mooring line 32 at the installation 22, and docking fenders 34 placed against the hull 24 along the rear edge 26.

The mooring line 32 has an end attached to the shell 24 along the rear edge 26 and a free end to be fixed on the transfer installation 22, as will be seen below.

In this example, the reservoir 30 comprises two liquefied hydrocarbon transfer manifolds (or "mani- folds") 36A, 36B to the plant 22, and a gaseous or liquefied hydrocarbon discharge collector 36C from the installation 22. The manifolds 36A to 36C open parallel to each other axially relative to the first vessel 18.

Each manifold 36A to 36C is advantageously provided at its outer end with a connection flange and a removable connection fitting adapted to protrude beyond the rear edge 26 for the connection of a fluid transfer line. . Such removable connection connectors are described for example in the French patent application No. 06 05434 and No. 07 54438 of the Applicant.

The second vessel 20 is for example a floating LNG transport vessel (designated in English by "LNG-Carrier" or LNG-C), suitable for conveying the liquefied hydrocarbon from its production site to a site of use.

The second vessel 20 comprises a hull 40 having two lateral edges 42A, 42B and a front end 44, and tanks 46 for storing liquefied hydrocarbons disposed in the hull 40.

The second vessel 20 further comprises ducts 48 for connection to the transfer facility 22 and at least one second line of tether 50 to the transfer facility 22, which in this example is the forward tip of the ship 20. The pipes 48 comprise two parallel axial pipes 52A, 52B of liquefied hydrocarbon transfer in the tanks 46, and an axial line 52C of gas discharge connected in parallel with the reservoir 46.

Each duct 52A to 52C extends substantially axially in the vessel 20. Each duct 52A to 52C has a connection flange 54A to 54C at its free end and advantageously a removable connection fitting, able to protrude beyond the front end 44 to the installation 22 for connecting a fluid transfer line. Such a connection is described in the French patent applications No. 06 05434 and 07 544 38 of the Applicant. The transfer installation 22 according to the invention comprises a floating support structure 60, a hydraulic distributor 62 for hydraulic connection between the first vessel 18 and the second vessel 20, mounted on the floating carrier structure 60, and means 66A, 66B of fixing the respective mooring lines 32, 50 of the first vessel 18 and the second vessel 20. In the example shown in Figures 1 to 3, the floating carrier structure 60 is a hull 60 partially immersed in the body of water 12, floating away from the bottom 14 of the body of water 12. It extends along an axis XX 'longitudinal.

The floating structure 60 is not anchored in the bottom 14 of the body of water. It floats freely over this area 12, being exclusively held in position by the mooring lines 32, 50. Advantageously, the transfer installation 22 may be provided with hydrodynamic positioning means ("trusters") in order to maintain the position of the installation 22 with respect to the ship 18 throughout the transfer operations. The floating carrier structure 60 thus has a submerged lower surface 68 and a substantially horizontal upper surface 70 for supporting the hydraulic distributor 62. It furthermore has two substantially vertical lateral surfaces 72 and two upstream and downstream end surfaces 74A, 74B. substantially vertical and opposite, which extend between the upper surface 70 and the lower surface 68.

The upper surface 70 extends above the surface 16 of the body of water 12. The end surfaces 74A, 74B extend substantially perpendicularly to the axis X-X 'respectively opposite the first vessel 18 and facing the second vessel 20.

As illustrated in FIG. 3, the distributor 62 comprises two parallel rigid lines 8OA, 8OB of liquid hydrocarbon transfer, a rigid gas delivery pipe 8OC, and a rigid bypass 83 connecting the rigid transfer pipes 8OA, 8OB between their ends.

The distributor 62 further comprises, at the ends of each rigid pipe 8OA to 8OC, an upstream hose 82A to 82C for the hydraulic connection to the first vessel 18 and a downstream hose 84A to 84C for the hydraulic connection to the second vessel 20. Hoses 'utility can be provided (instrumentation, nitrogen, air, electricity, telecommunication ...).

The dispenser 62 further includes hoists 86 for handling the hoses 82A-82C and 84A-84C, on which the hoses are held in a chain.

Each transfer line 8OA, 8OB extends axially along the shell 62 between an upstream end located in the vicinity of the upstream end surface 74A, and a downstream end located in the vicinity of the downstream end surface 74B. Each rigid pipe 80 to 8OC is provided, at its upstream end and at its downstream end, rotary joints 87 to which are connected the respective hoses 82A to 82C and 84A to 84C.

Each rigid pipe 8OA to 8OC is provided, in the vicinity of its upstream end, with an upstream valve 88 for selectively closing the pipe, and in the vicinity of its downstream end, with a downstream valve 90 for selective sealing. of driving.

The bypass line 83 is stitched onto both of the rigid transfer lines 8OA, 8OB between the upstream shut-off valves 88 and the downstream shut-off valves 90. The bypass pipe 83 is provided with a intermediate valve 92 selective shutter.

The valves 88, 90, 92 are able to be operated to selectively close or release the pipe on which they are placed. The rigid pipes 8OA, 8OB, 8OC are fixed with respect to the floating structure 60 and are held permanently above the surface 16 of the body of water 12.

As illustrated in FIGS. 1 to 3, each upstream hose 82A-82C has an end attached to the upstream end of each rigid pipe 8OA-8OC on a rotary joint 87, and a free end intended to protrude axially. away from the floating carrier structure 60 to the first vessel 18.

The upstream hoses 82A to 82C are hung in chain or catenary between their ends, so that they have substantially a shape of J. Thus, the hoses permanently occupy a configuration ensuring a high radius of curvature, which increases their duration of life. In this example the hoses are cryogenic tubes.

The hoses 82A-82C are flexible over substantially their entire length and extend in a vertical plane substantially parallel to the X-X 'axis, in the axial extension of the respective rigid pipes 8OA-8OC to which they are connected.

Each upstream hose 82A to 82C is displaceable by means of one of the cranes 86 between a retracted rest position, in which its free end is placed in the vicinity of or opposite the floating structure 60, and an extended position of connection to a manifold 36A to 36C of the first vessel 18, in which its free end protrudes axially away from the surface 74A towards the first vessel 18.

Each upstream hose 82A to 82C is provided at its free end with a connection piece to a manifold 36A to 36C and an emergency disconnection valve (not shown), and is connected to a handling winch 93. a crane 86.

Similarly, each downstream hose 84A-84C has one end attached to the downstream end of each rigid pipe 8OA-8OC on a rotary joint 87, and a free end intended to protrude axially away from the bearing structure. floating 60 to the second vessel 20.

The downstream hoses 84A to 84C are hung in chain or catenary between their ends so that they have substantially a shape of J. Thus the hoses permanently occupy a configuration ensuring a radius of high curvature, which increases their life. In this example, the hoses are cryogenic tubes.

The downstream hoses 84A to 84C are flexible over substantially their entire length and extend in a vertical plane substantially parallel to the axis X-X 'in the axial extension of the respective rigid pipes 8OA to 8OC to which they are connected.

Each downstream hose 84A to 84C is movable by means of one of the cranes 86 between a retracted position of rest, in which its free end is placed in the vicinity or opposite of the floating structure 60, and a deployed position of connection to an associated connecting flange 54A to 54C of the second vessel 20, in which its free end projects axially away from the surface 74B towards the second vessel 20.

Each downstream hose 84A to 84C is provided at its free end with a coupling end to a flange 54A to 54C and an emergency disconnection valve (not shown), and is connected to a handling winch 93. a crane 86.

In the example shown in FIG. 3, the distributor 62 comprises four handling cranes 86 placed respectively at the four corners of the supporting structure 60, each crane 86 comprising a winch 93. Thus, the upstream hoses 82A, 82B of the rigid pipes 8OA transfer,

8OB are maneuvered by the same crane 86 and downstream hoses 84A, 84B of these lines 8OA, 8OB are operated by the same crane 86.

Two other cranes 86 respectively operate the upstream hose 82C and the downstream hose 84C of the rigid 8OC gas delivery pipe. The upstream hoses 82A to 82C and the downstream hoses 84A to 84C are permanently maintained above the surface 16 of the body of water by the cranes 86.

The means 66A for fastening the mooring line 32 of the first vessel 18 comprise, for example, a fastening stud fixed on the upper surface 70 in the vicinity and along the upstream end surface 74A.

The means 66B for fixing the mooring line 50 of the second vessel 20 comprise, for example, a fastening stud fixed on the upper surface 70 in the vicinity and along the downstream end surface 74B. The operation of the transfer assembly 10 according to the invention will now be described.

Initially, the transfer facility 22 is brought into the vicinity of the first vessel 18 by placing the upstream end surface 74A of the floating carrier structure 60 opposite the trailing edge 26 of the hull 24 at a distance greater than 70 m of this rear edge 26. The axis XX 'of the installation 22 is substantially coincident with the axis of the shell 24.

Then, the first mooring line 32 is deployed from the first vessel

18 and is fixed on the upstream fastening pad 66A disposed in the vicinity of the upstream end surface 74A. In a variant, the ship 18 and the installation 22 can be kept permanently connected. The system will operate in a closed circuit via the valve 92 of the bypass 83 to maintain the ducts in temperature.

The cranes 84 are then operated to bring the free ends of the upstream hoses 82A to 82C in contact with the fittings on the respective manifolds 36A to 36C, by passing the hoses 82A to 82C from their rest position to their active position. The hydraulic connection between each upstream hose 82A to 82C and an associated manifold 36A to 36C is then achieved, maintaining the hoses in their chain configuration.

Then, the second vessel 20 is maneuvered to bring its front end 44 opposite the downstream end surface 74B. The axis of the second vessel 20 is then substantially coincident with the axis of the installation 22.

The second vessel 20 is then immobilized in position by keeping the front end 44 at a distance generally greater than 40 meters from the surface 74. The mooring line 50 of the second vessel 20 is fixed on the attachment stud 66B present in the vicinity of the downstream surface 74B.

Then, the cranes 86 are maneuvered to bring the free ends of the downstream hoses 84A to 84C to the ends 54A to 54C of the respective lines 52A to 52C on the second vessel 20, by passing the hoses 84A to 84C from their rest position to their active position. The hydraulic connection between each downstream hose 84A to 84C and an end 54A to 54C associated is then achieved, maintaining the hoses in their chain configuration. This being done, three parallel hydraulic paths are established between the tank 30 on the first vessel 18 and the tanks 46 on the second vessel 20 through successively and respectively the upstream hoses 82A to 82C, the rigid pipes 8OA to 8OC present on the structure carrier 60, and the downstream hoses 84A to 84C.

The liquefied hydrocarbon transfer operations between the first vessel 18 and the second vessel 20 are then performed.

Advantageously, and taking into account the presence of the valves 88, 90 and 92, the hydraulic paths extending through the rigid transfer lines 8OA, 8OB are purged and put at the temperature of the liquefied hydrocarbon by opening the upstream valves 88 and the bypass valve 92 and closing the downstream valves 90 on these lines.

For this purpose, a quantity of liquefied hydrocarbon present in the tank 30 is pumped in a loop through successively the upstream hose 82A, the rigid pipe 8OA, the bypass 83, the rigid pipe 8OB and the upstream hose 82B.

Advantageously, the purged fluid is transferred to a tank carried by the structure 60, before being evacuated by a system of pumps and valves.

Once the system is purged and warmed up, the intermediate shut-off valve 92 is closed and the downstream shut-off valves 90 are opened.

The liquefied hydrocarbon contained in the tank 30 on the first vessel 18 is then conveyed to the tanks 46 on the second vessel through the parallel hydraulic paths passing through the rigid pipes 8OA, 8OB.

In addition, during this transfer, the valves 88 and 90 present on the discharge pipe 8OC are open so that the gas displaced by the liquid and produced in excess by evaporation is able to flow if necessary since the second ship 20 to the first ship 18.

In the event of a serious problem during the transfer, the emergency disconnection valves on the upstream hoses 82A to 82C and / or on the downstream hoses 84A to 84C are disconnected, which makes it possible to interrupt the transfer and to move the vessels away. .

Thanks to the transfer installation 22, it is therefore possible to have a floating liquefied hydrocarbon transport assembly 10 that is particularly safe to use, since the safety distance between the ships 18, 20 is high given the length of the upstream and downstream hoses 82A to 82C, 84A to 84C, which is added to that of the rigid transfer lines 8OA to 8OC. In addition, the disconnection of hoses and thereby the remoteness of ships in case of emergency are facilitated. In addition, the presence in the hydraulic distributor 62 of two rigid pipes 8OA, 8OB connected in parallel and interconnected by a bypass 83, associated with operating valves 88 to 92, allows the purge and the heating of the hydraulic paths transfer, before the actual transfer of fluid. The presence of the floating carrier structure 60 connected to the two vessels 18, 20 by mooring lines, dampens the relative positions of the two ships 18, 20, especially in the open sea when the swell is formed. The transfer installation 22 thus allows the transfer of fluid under wave conditions greater than 3 meters in height. In addition, the transfer installation 22 makes it possible to offer better resistance to water hammers when the transfer of fluid is stopped abruptly thanks to the rigid pipes 8OA, 8OB and to the protective installations possibly connected to them (receiving valves and balloons ). This increases the life of hoses 82A to 82C and 84A to 84C. Alternatively, the floating carrier structure 60 is formed by a floating openwork lattice as described in the French application No. 07 57527 of the applicant. Advantageously, the openwork lattice has internal spaces for circulating the liquid of the body of water. The ratio of the volume of the interior spaces to the sum of the volume of the perforated lattice and the volume of the interior spaces is greater than 0.9, for example.

In another variant, the cranes 86 are carried by the respective ships 18, 20 and not by the floating carrier structure 60.

A second transport assembly 140 according to the invention is shown in FIGS. 4 and 5. Unlike the first transfer assembly 10, a lateral surface 72 of the carrying structure 60 of the transfer installation 22 is placed facing and in contact with the second vessel 20. Thus, the downstream hoses 84A to 84C extend substantially transversely with respect to the axis XX 'of the floating structure and with respect to the axis of the upstream hoses 82A to 82C. The rigid pipes 8OA to 8OC are bent near their downstream end to be connected to the downstream hoses 84A to 84C, substantially in the middle of the supporting structure 60.

The carrying structure 60 comprises a plurality of studs 66B for fastening the mooring lines of the second vessel 20 disposed on the upper surface 70 and distributed along the lateral surface 72.

The length of the carrier structure 60, taken along its axis X-X ', is thus greater than the distance separating the front end 44 of the lateral collectors 150A to 150C of the second vessel 20.

The second vessel 20 includes side collectors 150A to 150C which open transversely to a longitudinal axis of the second vessel 20. The collectors 150A to 150C are advantageously provided with removable connectors as previously described. They open into tanks 46.

The mooring lines of the second ship 20 on the transfer facility include, in addition to the nose 50, the rear tip 152, and intermediate lines 154 which are attached to the side edge 42B of the ship.

The operation of the second transport assembly 140 differs from that of the first assembly 10 in that the second vessel 20 abuts against the side surface 72 of the hull 60 for its hydraulic connection to the distributor 62.

Thus, the second vessel 20 comes into contact with docking defenses 156 placed against the surface 72. The nose 50, the rear tip 152 and the intermediate lines 154 are then secured to the mounting pads 66B present along the lateral surface 72, which blocks the second vessel 20 in position against the floating carrier structure 60. This being done, the downstream hoses 84A to 84C are maneuvers to move them transversely to the axis XX 'of the bearing structure 60 and connect them to the collectors 150A to 150C present in an intermediate part of the ship 20. The liquefied hydrocarbon transfer between the first vessel 18 and the second vessel 20 can then be carried out as described above. The transfer facility 22 of the second assembly 140 has the advantage of being usable with the collectors 150A to 150C present in the middle of the second vessel 20, without it being necessary to modify the structure of the vessel

20 to mount lines 48 opening at the front end 44 of this vessel.

Alternatively, the first vessel 18 is a LNG-C and the second vessel 20 is a floating storage and regasification unit (referred to as "Floating Storage and Regas Unit" or "FSRU") for storing and converting a vessel. hydrocarbon liquified into a gas for supply to an onshore facility.

Claims

1.- Installation (22) for transferring fluid between a first vessel (18) and a second vessel (20) floating on a body of water (12), of the type comprising a hydraulic transfer distributor (62) comprising: at least a first rigid pipe (80A, 80B, 80C) for transferring fluid; and for the or each rigid pipe (8OA, 8OB, 80C):

at least one upstream fluid transfer hose (82A, 82B, 82C), hydraulically connected to the rigid transfer line (8OA, 8OB, 80C) and intended to be connected to the first vessel (18); at least one downstream fluid transport hose (84A, 84B, 84C), hydraulically connected to the rigid transfer line (8OA, 8OB, 80C) and to be connected to the second vessel (20); characterized in that the installation comprises:

- a carrier structure (60) floating on the body of water (12), intended to be interposed between the first vessel (18) and the second vessel (20), the first rigid pipe (8OA, 8OB, 80C), the upstream hose (82A, 82B, 82C), and the downstream hose (84A, 84B, 84C) being mounted on the carrier structure (60);

at least one first means (66A) for attaching a first mooring line (32) of the first ship (18) to the supporting structure (60), arranged along a first mooring surface (74A) the carrier structure (60), the first mooring surface (74A) being adapted to be placed facing the first vessel (18);

at least one second means (66B) for attaching a second mooring line (32) of the second vessel (20) disposed along a second mooring surface (74B; 72) of the carrying structure (60); ), the second mooring surface (74B; 72) being adapted to be placed facing the second vessel (20).

2.- Installation (22) according to claim 1, characterized in that it comprises at least one handling assembly (86) carried by the carrier structure (60), the or each handling assembly (86) being able to move the upstream hose (82A, 82B, 82C) and the downstream hose (84A, 84B, 84C) between a rest position in which said hoses are retracted to the carrier structure; (60) and an active fluid transfer position in which said hoses are connected respectively to the first vessel (18) and the second vessel (20).

3. Installation (22) according to claim 2, characterized in that the upstream hose (82A, 82B, 82C) and the downstream hose (84A, 84B, 84C) are hanged in a chain on the or each handling unit (86) in the home position and in the active position.

4. Installation (22) according to any one of claims 1 to 3, characterized in that the first mooring surface (74A) and the second mooring surface (74B) are substantially parallel and opposite one to the other.

5. Installation (22) according to any one of claims 1 to 3, characterized in that the first mooring surface (74A) and the second mooring surface (72) are substantially perpendicular to each other. other.

6. Installation (22) according to any one of the preceding claims, characterized in that the hydraulic distributor (62) comprises:

a second rigid transfer line (80B) mounted parallel to the first rigid fluid transfer line (80A) on the supporting structure (60), and

- At least one branch (83) connecting the first rigid pipe (80A) to the second rigid pipe (80B), the bypass (83) being provided with at least one hydraulic valve (92) operable between a first configuration in which the first rigid pipe (80A) and the second rigid pipe (80B) are hydraulically connected and a second configuration in which the first rigid pipe (80A) is hydraulically isolated from the second rigid pipe (80B).

7. Floating assembly (10; 140) for fluid transport, characterized in that it comprises:

- a transfer facility (22) according to any one of the preceding claims; - a first ship (18) placed next to the first mooring surface

(74A) and connected to the first attachment means (66A) by at least one first mooring line (32), the upstream hose (82A, 82B, 82C) being hydraulically connected to the first vessel (18); a second vessel (20) placed opposite the second mooring surface (74B; 72) and connected to the second attachment means (66B) by at least one second mooring line (50), the downstream hose (84A , 84B, 84C) being hydraulically connected to the second vessel (20).

8. An assembly (10) according to claim 7, characterized in that an axial end (26) of the first vessel (18) extends facing the first mooring surface (74A), an axial end (44), ) of the second vessel (20) extending opposite the second mooring surface (74B), the first and second vessels (18, 20) thus being placed axially end to end on either side of the support structure (60).

9. An assembly (140) according to claim 7, characterized in that the second vessel (28) comprises a lateral surface (42), the lateral surface (42) of the second vessel (20) being placed facing the second surface mooring (72) parallel to an axis (X-X ') of the carrier structure (60).

10. An assembly (140) according to claim 9, characterized in that the first mooring surface (74A) and the second mooring surface (72) are perpendicular to each other, the end axial (26) of the first ship (18) being placed opposite the first mooring surface (74A), the lateral surface (42) of the second ship (20) being fixed to the second mooring surface (72).

11. A method of transferring fluid in a transport assembly (10; 140) according to any one of claims 7 to 10, characterized in that it comprises the following steps:

placing the first vessel (18) next to the first mooring surface (74A) of the supporting structure (60) and placing the second vessel

(20) facing the second mooring surface (74B; 72) of the carrier structure (60);

placing the or each first mooring line (32) between the first vessel (18) and the first attachment means (66A), and placing the second or each mooring line (50); ) between the second attachment means (66B) and the second vessel (20), - hydraulic connection of the upstream hose (82A, 82B, 82C) on the first vessel (18) and hydraulic connection of the downstream hose (84A, 84B, 84C) on the second vessel (20);

- transfer of fluid between the first vessel (18) and the second vessel (20) through successively the upstream hose (82A, 82B, 82C), the first rigid pipe (8OA, 8OB, 80C) and the downstream hose (84A, 84B, 84C).