Floating storage vessel and offshore wharf with extension

Abstract

Offshore wharf equipment, in various examples, includes a floating storage vessel deployed and moored to a seabed at the sea in a fixed heading orientation by a deployed mooring line, the floating storage vessel including a hull having a bow end and a stern end, the floating storage vessel has a bow end and a stern end, and an extension portion is fitted at one or both of the bow end and the stern end, and includes coupling means on the extension portion to couple the deployed mooring line to the floating storage vessel.

Description

Technical Field

[0001] The present invention relates to a deployably moored floating storage vessel and offshore terminal apparatuses in which a cargo ship is moored to the deployably moored floating storage vessel for offshore loading or unloading of fluid cargo. Background Art

[0002] Floating storage vessels can be used to store large quantities of fluid products at offshore locations. Floating storage vessels can be permanently moored at offshore locations and are sometimes visited by cargo ships for loading or unloading. Examples of such floating storage vessels include floating storage vessels known in the art as floating storage units (FSUs), floating storage and regasification units (FSRUs), and / or the like.

[0003] Today’s floating storage units are often converted from previously commissioned tankers. From a technical, schedule and commercial perspective, converting an existing in-service tanker into a floating storage unit is typically the preferred option in the industry.

[0004] A U.S. patent application with publication number US2019 / 0161146 describes a jetty-free offshore terminal in which a floating storage unit (FSU) is deployed and moored to the seabed at sea. In one example, the offshore terminal includes a jack-up platform having equipment for regasification on one side of the floating storage unit. Cargo ships are moored side by side to the other side of the floating storage unit from time to time so that the ship unloads the fluid cargo from the cargo ship to the FSU. Side-by-side mooring allows a hose for transferring fluid cargo to be connected between the cargo ship and the FSU without the need for a dedicated facility to deliver the hose across the sea to the cargo ship.

[0005] For large cargo ships, tugboat assistance may often be required to help control the lateral movement of the cargo ship toward the floating storage vessel for side-by-side mooring. The mooring lines used to moor the cargo ship to the floating storage vessel are passed and tensioned between the cargo ship and the floating storage vessel.

[0006] Bringing a large cargo vessel alongside a floating storage vessel moored by deploying mooring lines to a fixed heading orientation can be particularly challenging when doing so in adverse sea conditions. For example, it can be challenging to control the movement of the cargo vessel and auxiliary tugboat and provide the necessary fine control to bring the cargo vessel safely to the correct mooring position alongside the floating storage vessel. Summary of the invention

[0007] In examples disclosed herein, a floating storage vessel is provided, comprising a hull having a bow end and a stern end, at one or both of which there is an elongated extension protruding horizontally from an upper portion of the hull, the extension having at least two couplings spaced apart from each other on the extension, each coupling engaging a separate deployed mooring line. The floating storage vessel may also have further features as set forth in any dependent claim of the appended claims or anywhere else herein.

[0008] In an example disclosed herein, a floating storage vessel is provided, comprising a hull having a bow end and a stern end, an extension portion being installed at one or both of the bow end and the stern end, and comprising a coupling device on the extension portion for coupling a deployed mooring line to the floating storage vessel.

[0009] Typically, the hull comprises a hull deck located on top of the hull, and the extension is arranged to be aligned in height with the hull deck. The extension may comprise a box-shaped structure comprising an extension deck arranged at or near the level of the hull deck.

[0010] Typically, the extension comprises a box-shaped structure of welded plates. The extension deck is arranged on or incorporated into the structure of welded plates. The coupling device may be arranged on the extension deck or accessible by personnel from the extension deck.

[0011] In some examples, the extension portion includes a box-shaped structure extending from a first end to a second end in a horizontal direction, the first end of the box-shaped structure being connected to the hull at an upper position on a bow end or a stern end, wherein the box-shaped structure may be supported by at least one supporting member connected to the box-shaped structure at a position between the first end and the second end of the box-shaped structure or at the second end of the box-shaped structure, and connected to the hull at a lower position on the bow end or the stern end. For example, if provided on the stern, the lower position is close to a propeller position, or if provided on the bow, close to a bulb position.

[0012] In some examples, the extension portion includes a box-shaped structure comprising welded steel plates, wherein the structure is elongated to extend between a first end and a second end, and the extension portion is welded at the first end to join the box-shaped structure to the hull without requiring further connection of the box-shaped structure to the hull or other supporting components, so as to provide the extension portion in a working state at the bow end or the stern end of the hull.

[0013] Typically, the extension portion has a first end and a second end and extends in a horizontal extension direction between the first and second ends, the first end being weldably joined to the hull to assemble the extension portion to the hull, and the second end being arranged away from the joined first end.

[0014] The extension at one or both of the bow end and the stern end may be an offset extension and the extension is offset at an angle from the longitudinal axis of the hull.

[0015] The deployment mooring line may be or may include a deployment mooring chain.

[0016] In an example disclosed herein, an offshore dock device is provided, comprising: a floating storage vessel, which is deployed and moored to the seabed at sea in a fixed heading orientation by deploying mooring lines, the floating storage vessel comprising a hull extending along a longitudinal axis, the hull having a bow end and a stern end, and an elongated extension at one or both of the bow end and the stern end protruding away from the hull to be parallel to the longitudinal axis, the extension having at least four spaced-apart couplings arranged along a portion of the length of the extension, each coupling engaging a separate deployed mooring line. The offshore dock device may have other features as set out in any dependent claim of the claims attached hereto or as set out anywhere else herein.

[0017] In an example disclosed herein, an offshore dock equipment is provided, which includes: a floating storage vessel, which is moored to the seabed at sea in a fixed heading by deploying a mooring cable, the floating storage vessel including a hull having a bow end and a stern end, and an extension portion is installed at one or both of the bow end and the stern end, and includes a connecting device on the extension portion to connect the deployed mooring cable to the floating storage vessel.

[0018] A mooring area for mooring a cargo ship to a floating storage vessel may be provided in a defined area beside the floating storage vessel between the bow end and the stern end deployable mooring cables, so that mooring of the cargo ship beside the floating storage vessel may be facilitated without causing the hull of the cargo ship to overlap with or interfere with the deployable mooring cables.

[0019] In some examples, the floating storage vessel includes a bow extension and a stern extension, and the cargo ship is moored in a mooring area between the extensions next to the floating storage vessel, and the connecting device on the extension defines the departure point of the deployed mooring line from the floating storage vessel, so that at least a predetermined distance or gap is maintained between the deployed mooring line and the moored cargo ship in the horizontal direction, for example, at the nearest point at the bow or stern of the cargo ship.

[0020] By means of the extension, a mooring area can be provided so that a large cargo vessel can be moored alongside a floating storage unit with a safe clearance between the cargo vessel and the deployed mooring lines of the floating storage unit. Thus, the mooring area provided can provide accessibility for a tugboat to assist in mooring the cargo vessel near the floating storage vessel and facilitate safe movement and control of the cargo vessel when bringing the cargo vessel adjacent to the side of the floating storage vessel. The tugboat can be connected to and arranged relative to the cargo vessel and has additional options for tug line configuration and tugboat contact points against the cargo vessel so that the movement of the cargo vessel can be more finely controlled and regulated when the cargo vessel is brought alongside the floating storage vessel.

[0021] The cargo vessel can be brought into position and moored while more easily coping with challenging sea conditions. Thus, the quay can be arranged so that the floating storage vessel is in the form of a previously in-service tanker of typically 250m to 300m in length and is converted to be fitted with an extension and the cargo vessel is in the form of an in-service tanker of, for example, the same type, length and capacity as the floating storage vessel before the conversion.

[0022] The size matching or similarity between the cargo ship and the floating storage vessel can be beneficial to optimize operation. Therefore, advantageously, the length of the cargo ship can be equal to the length of the hull of the floating storage vessel, or generally differ from the length of the hull of the floating storage vessel by less than 5%. However, the cargo ship can have any length and a configuration that otherwise allows mooring alongside. In some variations, the length of the cargo ship can differ from the length of the hull of the floating storage vessel by less than 5% to 50% in length. The length of the hull of the floating storage vessel can be the length of the pre-converted hull to which the extension in an embodiment of the present invention is added. The cargo ship can be longer or shorter than the floating storage vessel, and / or longer or shorter than the pre-converted hull.

[0023] Typically, offshore terminal equipment also includes a cargo ship that is moored to a floating storage vessel in a side-by-side relationship for transferring fluid cargo between the cargo ship and the floating storage vessel. The cargo ship is moored in a mooring area between a bow end deployment mooring line and a stern end deployment mooring line. Side-by-side mooring can allow cargo transfer between the cargo ship and the floating storage vessel using a relatively short cargo transfer hose, reducing pressure losses when transferring fluids through the hose, and thus improving transfer capacity, while the mooring with the extension can be used to bring the cargo ship alongside more effectively or in adverse weather. Therefore, the terminal can provide improvements such as increased uptime, more efficient use of cargo transfer availability windows, and less time to complete cargo transfers.

[0024] Typically, the offshore terminal equipment also includes a first conduit for transferring fluid cargo between the cargo ship and the floating storage vessel. The cargo ship is typically moored so that the mid-ship manifold of the cargo ship is relatively positioned relative to the mid-ship manifold of the floating storage vessel. Therefore, the first conduit, which typically includes one or more hoses, can extend between the mid-ship manifold of the respective cargo ship and the mid-ship manifold of the floating storage vessel.

[0025] Typically, the offshore terminal equipment further includes a platform or a transfer tower supported on the seabed, and a second pipeline for transferring fluid cargo or gas between the floating storage vessel and the platform or the transfer tower.

[0026] Optionally, the platform may include a regasification facility for regasifying the unloaded fluid. The apparatus may then include a third pipeline for conveying the regasified fluid from the platform to shore. The third pipeline may include, for example, a subsea pipeline at the seabed.

[0027] Alternatively, the platform may include a liquefaction facility for liquefying fluid to be stored on a floating storage unit and transferred to the cargo vessel.The apparatus may then include a third pipeline, which may include a subsea pipeline, for conveying gas to the platform.

[0028] Preferably, the platform or transfer tower is arranged on the side of the floating storage vessel opposite to the cargo ship. The platform may conveniently be a jack-up platform comprising legs arranged to rest on the sea bed, and a hull jacked along the legs to be positioned above the wave zone above the sea surface.

[0029] Since the regasification or liquefaction facility can be set on the platform or supporting structure, such facilities and other facilities, such as a crane or lifting arm for connecting a second pipeline, etc., may not be required on the floating storage vessel, so that the floating storage vessel for the dock can be conveniently provided without the need for extensive modifications, and it helps to limit the time required for installing and assembling the dock.

[0030] Typically, the hull of the floating storage vessel is modified from the original hull by adding the extension (which may typically be a prefabricated unit) to the bow or stern end. The extension may include a cantilever protruding from the original bow or stern end. The length of the extension may be sufficient to position the connection point of the extension's deployment mooring chain beyond the original bow or stern end so that a cargo ship, preferably of the same size as the original (i.e., unmodified) floating storage vessel or perhaps slightly longer, may be safely moored between the bow and stern deployment mooring chains without the hull of the cargo ship or tugboat interfering with or horizontally overlapping the deployment mooring lines extending laterally from the floating storage vessel.

[0031] Preferably, the deployment mooring line is provided in a catenary configuration. In the catenary configuration, one end of the deployment mooring line is connected to a coupling device at a position as high as possible above the sea surface of the floating storage vessel and / or the extension (e.g. at or near deck level), and the other end of the deployment mooring line is connected to an underwater mooring member on the seabed.

[0032] Preferably, the offshore terminal is a shallow water offshore terminal. The floating storage vessel can be deployed and moored in shallow water, the water depth in the shallow water is in the range of up to 50m. Therefore, the system can be used to unload fluid cargo at a suitable near-shore shallow water location, and the fluid can be transported to the shore through a relatively short submarine pipeline.

[0033] In order to obtain an acceptable catenary shape of the mooring line in a catenary configuration, it may be preferred to use a deploying mooring line that is deck mounted or otherwise mounted as high as possible to the floating storage vessel (i.e., not keel mounted). The catenary shape in the deploying mooring line can allow for dynamic vessel motions of the floating storage vessel in heavy sea conditions with acceptable mooring line forces.

[0034] A deployment mooring line, such as a deployment mooring chain, at the bow end extends away from the floating storage device at a first deployment angle relative to the longitudinal axis of the floating storage vessel. A deployment mooring line, such as a deployment mooring chain, at the stern end extends away from the floating storage vessel at a second deployment angle relative to the longitudinal axis of the floating storage vessel.

[0035] The fluid cargo may be any fluid cargo, such as any one or more of the following: liquid; gas; a mixture of liquid and gas; liquefied natural gas (LNG); liquefied petroleum gas (LPG); liquefied ammonia; liquefied hydrogen; liquefied carbon dioxide (CO2); or the like.

[0036] In an example disclosed herein, a method for using offshore dock equipment is provided, the method comprising: mooring a floating storage vessel to the seabed at sea in a fixed heading by deploying a mooring cable, the floating storage vessel comprising a hull having a bow end and a stern end, and being equipped with an extension portion at one or both of the bow end and the stern end, and comprising a connecting device on the extension portion to connect the deployed mooring cable to the floating storage vessel, and unloading fluid cargo from a cargo ship to the floating storage vessel.

[0037] In some examples, the method may further include transferring the unloaded fluid cargo from the floating storage vessel to shore using a transfer tower.

[0038] In certain other examples, the method may also include any one or more of the following: transferring the unloaded fluid cargo from the floating storage vessel to one or more platforms; performing any of the following on the one or more platforms: processing the fluid cargo, the fluid cargo including liquefied gas; regasifying the liquefied gas to produce regasified gas; using the regasified gas to generate electricity; using the generated electricity to generate water; and transferring or transporting the regasified gas or the generated electricity or the generated water to shore or another facility.

[0039] In an example disclosed herein, a method for using offshore dock equipment is provided, the method comprising: mooring a floating storage vessel to the seabed at sea in a fixed heading by deploying a mooring cable, the floating storage vessel comprising a hull having a bow end and a stern end, and being equipped with an extension portion at one or both of the bow end and the stern end, and comprising a connecting device on the extension portion to connect the deployed mooring cable to the floating storage vessel, and loading fluid cargo from the floating storage vessel onto a cargo ship.

[0040] In some examples, the method may further include transferring the fluid cargo from shore to the floating storage vessel.

[0041] In some examples, the terminal equipment may include at least one platform, and the method may include exporting gas from the shore to the platform, processing the gas on the platform, liquefying the gas, and transferring the liquefied gas from the platform to the floating storage vessel, the fluid cargo to be loaded including a certain amount of liquefied gas.

[0042] In an example disclosed herein, an extension portion for a floating storage vessel is provided, the floating storage vessel comprising a hull, the hull comprising one or more cargo tanks or boxes for storing fluid in the hull, the hull extending along a longitudinal axis between a bow end and a stern end, the extension portion comprising: an elongated structure extending parallel to the longitudinal axis between a first end and a second end, the first end of the structure being attached to the stern end or the bow end of the hull, wherein the second end is arranged away from the stern end or the bow end; a plurality of couplings spaced apart from each other along the structure for coupling deployed mooring lines to the extension portion. The extension portion may have other features as described in any of the attached dependent claims or as described anywhere else herein.

[0043] In an example disclosed herein, an extension portion for a floating storage vessel is provided, the floating storage vessel including a hull including one or more cargo holds or tanks in the hull for storing fluid, the hull including a longitudinal axis and extending longitudinally between a bow end and a stern end, the extension portion including: a structure extending between a first end and a second end, the first end of the structure being configured to be attached to the stern end or bow end of the hull, wherein the second end is arranged away from the stern end or stern end; and a connecting device supported on the structure for connecting a deployed mooring cable to the extension portion.

[0044] Typically, the structure comprises or consists essentially of welded steel plates.

[0045] Typically, the structure comprises or is an elongated box-shaped structure.

[0046] Typically, the first end of the structure may be welded to the bow or stern end of the hull to join the structure to the hull. The structure may be configured to be fully supported for operational use only by joining the first end of the box-shaped structure.

[0047] Typically, the structure has a deck for personnel to access the coupling device, and the coupling device is supported on the deck.

[0048] Typically, the hull comprises a hull deck, and the structure is configured to be connected to the hull, the structure being aligned in height with the hull deck.

[0049] Typically, the structure extends longitudinally relative to the hull from a first end to a second end. Alternatively, the structure extends from a first end to a second end in a direction that is angularly offset from the longitudinal axis of the hull. The structure may include a bend or dog leg section between the first and second ends of the structure such that the structure extends along the bend or dog leg section away from the longitudinal direction of the hull.

[0050] In an example disclosed herein, a method for providing a deployable moored floating storage vessel is provided, the deployable moored floating storage vessel being used to facilitate loading or unloading operations of fluid cargo in an offshore terminal, the method comprising: providing a tanker comprising one or more tanks or cargo holds for storing fluid and comprising a hull extending between a bow end and a stern end, the tanker being expected to be transformed into a floating storage vessel for deployable mooring in a fixed heading orientation in an offshore terminal during a transformation process; prefabricating at least one extension portion, the extension portion comprising a structure extending between a first end and a second end, and a coupling device supported on the structure, the coupling device being used to couple a deployed mooring line to the extension portion; connecting the first end of the prefabricated structure to the bow end or the stern end of the hull, attaching the extension portion to the hull, the second end of the structure being arranged away from the stern end or the bow end; and obtaining a floating storage vessel equipped with the at least one extension portion, deploying and mooring the floating storage vessel to a seabed mooring member, coupling the deployable mooring line to the extension portion using the coupling device on the extension portion. The method may also include: before the transition, operating a tanker to transport fluid cargo from one location across the sea to another location; after the transition, operating the floating storage vessel in the offshore terminal to store fluid to be loaded onto the cargo ship or to store fluid unloaded from the cargo ship.

[0051] In an example disclosed herein, an offshore fluid cargo handling facility is provided, comprising: an offshore platform for handling fluid cargo; a floating storage vessel, the floating storage vessel being deployed and moored near the offshore platform via a plurality of deployable mooring cables, the floating storage vessel comprising a hull extending along a longitudinal axis, the hull having a bow end and a stern end, wherein an elongated extension protrudes away from the hull at each of the bow end and the stern end to be parallel to the longitudinal axis, each extension having a first elongated side and a second elongated side, the first elongated side and the second elongated side having at least three connectors longitudinally spaced apart from each other along each elongated side, wherein one of the plurality of deployable mooring cables is attached to each connector; one or more aerial fluid cargo hoses, the one or more aerial fluid cargo hoses extending between the offshore platform and the floating storage vessel; a fluid cargo ship, the fluid cargo ship having a bow end and a stern end and being moored to the floating storage ship so that the bow end and the stern end of the fluid cargo ship are spaced apart from the deployable mooring cables of the floating storage ship. The offshore fluid cargo handling facility may have other features as set out in any claim dependent upon the appended claims or as set out anywhere else herein.

[0052] Embodiments of the invention may be advantageous in various ways, as will be apparent throughout this document. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0054] Figure 1 is a plan view representation of an offshore terminal installation according to one example, wherein a cargo vessel and a floating storage vessel are moored in a side-by-side relationship;

[0055] Figure 2 The cargo ship is shown being brought alongside the floating storage vessel to be moored to the Figure 1 A plan view representation of the floating vessel shown;

[0056] Figure 3 is a plan view representation of an offshore terminal facility including a transfer tower according to another example;

[0057] Figure 4A & Figure 4B yes Figure 3 A front perspective view and a rear perspective view of an offshore terminal equipment;

[0058] Figure 5 is a plan view representation of an offshore terminal installation in which the floating storage is fitted with offset extensions at the bow and stern ends respectively to allow greater safety clearance between vessels; and

[0059] Figure 6 is a larger scale schematic side view representation of the bow end portion of a floating storage vessel fitted with an extension. DETAILED DESCRIPTION

[0060] refer to Figure 1 and Figure 2 , the offshore terminal equipment 1 comprises a floating storage vessel 10, which is deployed and moored to the seabed at sea. At the bow end 10a, the floating storage vessel 10 is equipped with a first extension part 15a, and at the stern end 10b, the floating storage vessel 10 is installed with a second extension part 15b. Each of the extension parts 15a, 15b is provided with a coupling device to couple the deployed mooring lines 16a, 16b to the extension parts 15a, 15b, respectively.

[0061] The storage vessel 10 is deployed moored by means of deployable mooring cables 16a, 16b oriented in a fixed heading relative to the seabed. The bow end deployable mooring cable 16a extends from the bow end extension 15a to the mooring member 18a on the seabed. The stern end deployable mooring cable 16b extends from the stern end extension 15b to the mooring member 18b on the seabed. Each deployable mooring cable 16a, 16b has a first end connected to the coupling device 86a, 86b on the extension 15a, 15b and a second end connected to the mooring member 18a, 18b. The first end of the deployable mooring cable 16a, 16b is connected to the extension 15a, 15b above the sea level, usually at or near the deck level of the hull of the floating storage vessel or the extension. The second end of the deployable mooring cable 16a, 16b is connected to the seabed mooring member 18a, 18b underwater at or near the seabed. Thus, the deployed mooring lines 16a, 16b penetrate the water surface on their trajectory from the extension portions 15a, 15b towards the seabed mooring members 18a, 18b.

[0062] The deployment mooring line 16a extends away from the floating storage vessel 10 in a direction D that forms a deployment angle α with respect to the longitudinal axis 19 of the floating storage vessel. The deployment mooring line 16b extends away from the floating storage vessel 10 in a direction E that forms a deployment angle β with respect to the longitudinal axis 19 of the floating storage vessel 10 that is opposite to the deployment angle α.

[0063] A mooring area 33 is defined alongside the floating storage vessel between the bow end deployment mooring line 16a and the stern end deployment mooring line 16b.

[0064] exist Figure 1 In the embodiment, the cargo ship 20 is moored in a parallel side-by-side configuration in a safe mooring area 33 beside the floating storage vessel. The cargo ship 20 is moored to the floating storage vessel 10 via mooring lines 26a, 26b at the bow and stern ends. The cargo ship 20 abuts against the floating storage vessel on the soft fenders 27 located between the opposite hull sides of the floating storage vessel 10 and the cargo ship 20.

[0065] exist Figure 2 In FIG. 1 , a cargo ship 20 is approaching a floating storage vessel 10 , moving laterally toward a safe mooring area 33 as indicated by arrow A. The cargo ship 20 moves using its thrusters, and is further assisted by some pushing and some pulling by a tugboat 43 to control the speed and position of the cargo ship 20 .

[0066] By means of extensions 15a, 15b, mooring cables 16a, 16b are positioned away from cargo ship 20. Safety gaps 34a, 34b are established between the hull of the moored cargo ship 20 and the nearest mooring cables 16a, 16b at each end of the mooring. Preferably, the extension is arranged so that the defined safety gap provides a gap of at least 20m between the mooring cables 16a, 16b and the cargo ship when moored. The hull of the cargo ship 20 generally has a length that is the same or similar to the length of the floating storage vessel 10 before being equipped with extensions 15a, 15b. The mooring area 33 can allow a cargo ship 20 of the same or slightly larger size as the floating storage vessel to be brought to the side more easily and / or under control under adverse conditions. The tugboat 43 that may be needed for the auxiliary cargo ship 20 can be operated at a more advantageous position relative to the cargo ship, and can be operated in the operating area between the mooring cables deployed at the bow end and the stern end, while maintaining a predetermined gap distance, such as the same distance as the safety gap, with the nearest mooring cable. Tugboat can operate in mooring area 33 before cargo ship arrives beside floating storage ship completely.Therefore, it is feasible to deploy mooring structure for transferring fluid cargo from large tanker side to side.Cargo ship 20 (such as tanker) for fluid cargo transportation and unloading or loading at offshore fluid transfer terminal is usually available as part of world fleet "ready-made", but they usually have similar size, and variation is limited.When floating storage ship 10 is also of the same type, that is, when floating storage ship 10 is not working, it may often occur in the prior art that available cargo ship is not suitable for mooring side by side beside floating storage ship.Providing the solution of extension part 15a, 15b allows the deployment mooring of floating storage ship, and it has greater freedom, to safely manipulate cargo ship 20 beside floating storage ship.Cargo ship 20 can be brought to the side and moored, and will not cross safety gap 34a, 34b towards deployment mooring chain. By installing the floating storage vessel 10 with the extensions 15a, 15b, it is also possible to conveniently provide suitable safety clearances in the quay suitable for the specific project requirements and size of the cargo vessel 20, with due regard for possible sea conditions.

[0067] Still reference Figure 1 and Figure 2, the offshore terminal equipment 1 additionally has a seabed support platform, in this example a jack-up platform 50, which includes a processing facility 52 for processing fluid cargo. The platform 50 is arranged in the area between the bow end and the stern end of the mooring chain on the other side of the floating storage vessel. For the purpose of this example, the processing facility 52 is a regasification facility for regasifying the gas from the floating storage vessel unloaded from the cargo ship. In other variations, the processing facility 52 can be a combined regasification and power generation facility, which can also include a system for fresh water generation. Alternatively, the platform can be a liquefaction facility for liquefying the gas to be stored in the floating storage facility to be loaded onto the cargo ship. The jack-up platform 50 has legs supported on the seabed, and a hull that is lifted to a position above the sea surface away from the wave area along the jack-up legs. A personnel bridge 51 spanning above the sea surface extends between the platform 50 and the floating storage vessel 10.

[0068] In use, a fluid cargo in the form of liquefied gas is unloaded from the cargo ship 20 to the floating storage vessel 30 through a first pipeline in the form of one or more aerial hoses 61 or other loading equipment, which is connected between the mid-ship manifolds 12, 22 of the floating storage vessel 10 and the cargo ship 20. The unloaded liquefied gas is stored in the floating storage vessel 30. The liquefied gas is transported to the platform 50 through a second pipeline in the form of one or more aerial hoses and regasified by regasification. The regasified gas is then transferred away from the platform 50, usually to shore via a gas pipeline 63.

[0069] In a variation where the processing facility on the platform 50 is a liquefaction facility, in use, the gas is typically transferred from shore to the platform via a gas pipeline 63. The gas is liquefied by the liquefaction facility and then transferred to a floating storage vessel 10 storing the liquefied gas via a second hose 62. The liquefied gas is loaded from the floating storage vessel 10 to the cargo ship 20 via a first hose 61.

[0070] Now go to Figure 3 , Figure 4A and Figure 4B, the offshore terminal equipment 101 is a variation of the above-mentioned equipment 1, in which instead of a jack-up platform, it includes a transfer tower 150. The transfer tower is supported on the seabed at the foot of the tower. The tower extends upward through the sea surface and extends upward beyond the wave action area to a height near the deck level or the level of the midship manifold 112. The aerial hose 62 extends between the transfer tower 150 and the midship manifold 112 of the floating storage vessel 10 above the wave action area, thereby minimizing the risk of damage to the hose by wave forces during extreme wave conditions. A third pipeline in the form of a pipeline 63 usually extends along the seabed from the foot or submerged part of the tower. The fluid is transferred between the floating storage vessel 30 and the pipeline 63 through the tower and the hose 62 in use. The tower 150 has a conduit along the tower, such as from the upper end above the sea surface to the lower end below the sea surface, for transferring fluid cargo between the hose 62 and the pipeline 63 during unloading or loading operations. In this example, liquefaction or regasification can be carried out on land. Therefore, the fluid cargo is directly transferred to or from the floating storage vessel 10 through the transfer tower 150 without processing. In this case, in order to keep the gas in liquid form, the pipeline may be insulated, such as a pipe-in-pipe pipeline.

[0071] exist Figure 6 , the bow end of the floating storage vessel 10 is depicted in more detail, wherein the extension 15a is mounted to the bow end. Figure 6 The floating storage vessel 10 with the extension 15a shown is provided with a designated tanker to be adapted, the designated tanker comprising a hull 71 and one or more boxes 13 in the hull, and then the extensions 15a, 15b are assembled to the hull 71 of the designated tanker. To facilitate this, the extensions 15a, 15b include a box-shaped structure 80, which is prefabricated and ready to be assembled to the tanker. It should be understood that the extension 15b can be constructed and connected at the stern end in a manner corresponding to the extension 15a for the bow end described herein. Therefore, for the sake of brevity, only the bow end structure and the extension 15a are described in detail below.

[0072] The box-shaped structure 80 is configured to assemble the bow end 73 at the connection position 73h on the bow end 73, and the box-shaped structure 80 is welded to the bow end 73 of the hull 71 at the connection position 73h. One or more boxes 13 are provided in the hull 71 for storing fluids to be unloaded from the cargo ship or to be loaded onto the cargo ship during use. The box-shaped structure 80 extends longitudinally away from the connection position 73h. In other examples, the box-shaped structure 80 may include a prismatic structure.

[0073] On the upper part of the hull 71, the hull has a hull deck 79, which includes a walkway and / or an area for personnel or crew members to enter. Other decks (not shown) can be provided as a part of the hull superstructure. The hull deck 79 can be equipped with loading and unloading equipment operated, approached and / or checked by the personnel on board, and the equipment includes, for example, lifting and loading and unloading equipment, or is convenient for mooring the cargo ship 20 to the side. The personnel standing on the hull deck 79 can also approach the midship manifold 12, so that one or more fluid cargo transfer hoses 61 are connected, for loading or unloading fluid cargo into the cargo hold or box 13 in the hull. The hull 71 in the middle part between the stern end and the bow end defines the maximum width of the hull 71. The width of the hull 71 at certain positions along the hull 71 is usually tapered towards the bow end 73 and away from the entire width of the middle part towards the stern end respectively.

[0074] The box structure 80 of the extension 15a preferably comprises welded steel plates. The box structure 80 preferably has a height H less than the top side height F of the hull 71 above the waterline 36, and preferably has a width less than the maximum width of the hull at the middle part, such as typically less than half of the maximum width of the hull at the middle part or less than a quarter of the maximum width of the hull at the middle.

[0075] The box-shaped structure 80 extends from a first end 81 to a second end 82. The first end 81 of the box-shaped structure 80 abuts against and is welded to the bow end 73 at the connection position 73h to connect the box-shaped structure 80 to the hull 71. The box-shaped structure 80 is elongated and extends longitudinally in the longitudinal direction of the hull from the first end 81 at the connection position 73h toward the second end 82. Therefore, the box-shaped structure 80 provides a longitudinal extension from the hull at the bow end. The structure protrudes longitudinally from the outer surface of the bow end at the connection position 73h toward the second end 82, and the second end 82 is arranged distally relative to the first end 81.

[0076] The box structure 80 is also arranged to be welded to the connection position 73h on the bow end 73 at or near the top of the hull, so that the box structure 80 is aligned with the hull deck 79. In this way, by welding the first end 81 to the bow end 73, the hull 71 can support the box structure 80, and the connection device 86a on the box structure 80 is used for the deployment mooring line 16a located high on the hull, and also benefits from the inherent strength of the hull 71 at or near the deck height of the hull, so that the necessary mooring loads can be handled.

[0077] The extension 15a also includes an extension deck 89 located on the upper portion of the box structure 80. When the extension 15a is attached to the hull 71, as shown in FIG. Figure 6As shown, the deck 89 of the extension 15a is located at or near the same height as the hull deck 79. This arrangement can promote a strong and rigid welded structural connection of the box structure 80 to the hull 71.

[0078] exist Figure 6 In the example of , the box-shaped structure 80 is additionally supported by a tubular support member 91 extending from one end 91a connected to the box-shaped structure 80 at a position along the box-shaped structure 80 in the extension direction to the other end 91b connected to the bow end at the lower connection position 73i, the lower connection position 73i being positioned lower than the connection position 73h. For example, at or near the waterline 36, such as at or near the spherical member 73b at the bow end, or in the case of the stern extension 15b, such as at or near the propeller position. However, in other examples, it may be sufficient for the box-shaped structure 80 and the box-shaped structure 80 to be connected to the hull surface at the bow end alone, wherein the box-shaped structure 80 extends longitudinally from the bow end of the hull toward its second end 82 from the first end 81 at the connection position 73h. The box structure 80 is then sufficient (by simply connecting the first end 81 at 73h) to withstand the mooring loads applied from the deployed mooring lines 16a by the forces applied to the floating storage vessel 10 under prevailing sea conditions.

[0079] The extension 15a typically comprises a prefabricated welded steel plate structure 80 which can be fabricated at the yard in due time before the tanker arrives at the yard. The coupling means 86a for the mooring chains are typically installed on the prefabricated extension 15a before the ship arrives, so that everything is ready when the ship arrives at the yard. In this way, the extension 15a can be quickly "added" to the ship, i.e. welded on the ship, and the ship can stay at the yard for a limited time.

[0080] In practice, the box structure 80 or other welded plate structure has, for example, a height of 5 m or more.The length of the extension 15a may be determined from one nose to another depending on the size of the cargo ship 20 planned to be moored to the floating storage vessel 10 in a side-by-side mooring arrangement.

[0081] A coupling device 86a is fitted to the extension 15a for coupling a mooring cable 16a, typically in the form of a mooring chain, to the extension 15a. Each extension typically has 6-10 chains, each of which can be connected to a separate coupling device 16a, although six mooring cables per extension are shown in the drawings. In some examples, the coupling device 86a is of an "adjustable type" so that after the chain is pulled in, the chain tension can be adjusted by pulling in more chain or loosening the chain using the adjustable coupling device. The adjustable device is used, for example, after the vessel 10 has been operating for a period of time to re-tension the mooring cable 16a when necessary. In some examples, the coupling device 86a is equipped with a load monitoring device to continuously monitor the mooring chain load during operation. This can ensure that the mooring tension is evenly distributed between all chains. Load monitoring can be particularly beneficial during operation in bad weather to ensure that the mooring tension is within acceptable levels. In some examples, the coupling device 86a is a releasable type, that is, the coupling device 86a has a release mechanism, so that if the ship 10 must leave the position (for example, during abnormal bad weather), the mooring line 16a can be released from the extension 15a. This release mechanism can be remotely operated, for example, by hydraulic or other devices. The coupling device 86a is supported on the deck 89 of the extension 15a, usually at or near the extension deck level. The coupling device 86a on the extension 15a is sufficient, and the coupling device required for the bow end connection of the carrying deployment mooring line 16a and the ship is not required. Any connection of the hull between the mooring line 16a and the extension is not required. This is also applicable to the stern using the extension 15b. In this way, the mooring area for the cargo ship 20 can be defined between the extensions 15a, 15b beside the floating storage vessel 10.

[0082] Figure 5The offshore terminal equipment 201 is similar to the above-described device 1, but in this example, the floating storage vessel 10 is equipped with deviated extensions 215a, 215b at the bow end 10a and the stern end 10b. That is, the deployment mooring lines 16a, 16b are located away from the central longitudinal axis 19 of the hull 71 from the exit point of the extensions 215a, 215b. In particular, in this example, the extensions 215a, 215b extend in a deviated direction from the proximal first end 281a, 281b toward the distal second end 282a, 282b, the proximal first end 281a, 281b being connected (i.e., retrofit welded) to the bow or stern of the vessel, the deviated direction extending from the central longitudinal axis of the hull 71 at an angle Y, Y'. The extension 215a at the first end 281a, 281b is welded to the bow end or the stern end of the ship 10 to extend and protrude from the hull surface on the bow end or the stern end. The coupling device 86a, 86b provides a departure point for the mooring line 16a, 216b toward the seabed mooring member on the extension 215a, 215a. The deviated extension 215a, 215b is away from the longitudinal axis 19 and away from the side of the mooring area 33 of the ship 10 for accessing the cargo ship 20. When moored in the mooring area 33, this can allow a larger gap or safety gap 234a, 234b between the unfolded mooring line 16a, 16b and the cargo ship 20. By changing the angle Y, Y' and the length of the deviated extension 215a, 215b between the first end and the second end, an optimized safety gap 234a, 234b can be obtained to fit the specific project requirements and size of the cargo ship 20. The angle of deviation may vary in different examples, as desired. The deviated extensions 215a, 215b may be otherwise configured in terms of structure and connection, as described above with respect to any of the other extensions described above.

[0083] In any of the examples described herein, the floating storage vessel may be a floating storage unit (FSU), and in particular examples, the floating storage unit may be a floating storage and regasification unit (FSRU).

Claims

1. A floating storage vessel comprising a hull having a bow end and a stern end, one or both of which has an elongated extension projecting horizontally from an upper portion of the hull, the extension having at least two couplings spaced apart from each other on the extension, each coupling engaging a separate deployed mooring line.

2. The floating storage vessel according to claim 1, in, The hull comprises a hull deck, and the extension portion is arranged to be aligned in height with the hull deck.

3. The floating storage vessel according to claim 1 or claim 2, in, The extended portion includes a box-shaped structure of welded plates and an extended deck on the box-shaped structure.

4. The floating storage vessel according to claim 3, in, The coupling coupler is arranged on the extension deck or is accessible by personnel from the extension deck.

5. A floating storage vessel according to any preceding claim, in, The extension portion includes a box-shaped structure, which extends from a first end to a second end in a horizontal direction, and the first end of the box-shaped structure is connected to the hull at an upper position on the bow end or the stern end, wherein the box-shaped structure is capable of being supported by at least one supporting member, and the at least one supporting member is connected to the box-shaped structure at a position between the first end and the second end of the box-shaped structure or at the second end of the box-shaped structure, and is connected to the hull at a lower position on the bow end or the stern end, if it is set on the stern, the lower position is close to the propeller position, or if it is set on the bow, the lower position is close to the bulb position.

6. A floating storage vessel according to any preceding claim, in, The extension portion comprises a box-shaped structure comprising welded steel plates, wherein the box-shaped structure is elongated to extend between a first end and a second end, the extension portion is welded at the first end to connect the box-shaped structure to the hull at the bow end or the stern end, the connection of the first end of the box-shaped structure being the only connection or the only required connection of the structure to the hull.

7. A floating storage vessel according to any preceding claim, in, The extension portion at one or both of the bow end and the stern end has a first end and a second end, the first end of the extension portion being connected to the hull at the bow end or the stern end and extending from the first end toward the second end in the longitudinal direction of the hull.

8. A floating storage vessel according to any preceding claim, in, The hull has a longitudinal axis, and the extension portion at one or both of the bow end and the stern end is an offset extension portion, wherein the offset extension portion extends from a first end toward the second end at an angle to the longitudinal axis, and the first end is connected to the hull from the bow end or the stern end.

9. A marine terminal equipment, include: A floating storage vessel, which is moored to an offshore seabed in a fixed heading direction by deploying mooring lines, the floating storage vessel comprising a hull extending along a longitudinal axis, the hull having a bow end and a stern end, and an elongated extension at one or both of the bow end and the stern end protruding away from the hull to be parallel to the longitudinal axis, the extension having at least four spaced-apart connectors arranged along a portion of the length of the extension, each connector engaging a separate deploying mooring line.

10. The offshore terminal facility of claim 9, further comprising a cargo ship moored to the floating storage vessel in a side-by-side relationship for transferring fluid cargo between the floating storage vessel and the cargo ship.

11. The offshore terminal equipment according to claim 10, in, The cargo ship is moored in a mooring area between the bow end deployment mooring line and the stern end deployment mooring line.

12. The offshore terminal equipment according to claim 10 or claim 11, in, The floating storage vessel comprises a bow extension and a stern extension, and the cargo ship is moored in a mooring area between the extensions beside the floating storage vessel, the connector on the extension defining a departure point for the deployed mooring cable so that at least a predetermined distance or gap is maintained horizontally between the nearest deployed mooring cable and the moored cargo ship in the mooring area.

13. The offshore terminal equipment according to any one of claims 10 to 12, in, The cargo vessel is typically moored so that the midship manifold of the cargo vessel is positioned opposite the midship manifold of the floating storage vessel.

14. The offshore terminal facility according to any one of claims 10 to 13, further comprising a first pipeline for transferring fluid cargo between the floating storage vessel and the cargo ship.

15. The offshore terminal equipment according to any one of claims 10 to 14, further comprising a platform or transfer tower supported on the sea bed, and a second pipeline for transferring fluid cargo between the floating storage vessel and the platform or transfer tower structure.

16. The offshore terminal equipment according to claim 15, further comprising the platform, and wherein the fluid cargo is liquefied gas, and a regasification facility on the platform for regasifying the liquefied gas.

17. The offshore terminal equipment according to any one of claims 10 to 16, further comprising a third pipeline for transferring the fluid cargo between the platform or the transfer tower and the coast.

18. The offshore terminal equipment according to claim 15, in, The platform or transfer tower is arranged on a side of the floating storage vessel opposite to the cargo ship.

19. The offshore terminal equipment according to any one of claims 9 to 18, in, Elongated extensions at both the bow and stern ends project away from the hull to be parallel with the longitudinal axis, the extensions having at least four spaced apart couplers disposed along a portion of the length of the extensions, each coupler engaging a separate deployed mooring line.

20. An extension for a floating storage vessel, the floating storage vessel comprising a hull including one or more tanks or compartments for storing fluids in the hull, the hull extending along a longitudinal axis between a bow end and a stern end, the extension include: an elongated structure extending parallel to the longitudinal axis between a first end and a second end, the first end of the structure being secured to the stern end or the bow end of the hull and the second end being disposed distally from the stern end or the bow end; A plurality of couplers are spaced apart from one another along the structure for coupling deployed mooring lines to the extension portion.

21. The extension portion according to claim 20, in, The structure comprises welded steel plates.

22. The extension portion according to claim 21, in, The structure comprises an elongated box-shaped structure or an elongated box-shaped structure.

23. The extension portion according to claim 22, in, The first end of the box-shaped structure can be welded to the bow end or the stern end of the hull to join the box-shaped structure to the hull, and the box-shaped structure is configured to be fully supported for operational use only by the joining of the first end of the box-shaped structure to the hull.

24. An extension portion according to any of claims 20 to 23, in, The structure also includes a deck for crew or personnel entry, and the plurality of couplings are arranged along the deck.

25. An extension portion according to any of claims 20 to 24, in, The hull includes a hull deck, and the structure is configured to be connected to the hull, the structure being aligned with the hull deck.

26. An extension portion according to any of claims 20 to 25, in, The structure extends from the first end to the second end along a curve or sharp turn.

27. An extension portion according to any one of claims 20 to 26, in, The elongated structure has a first side and a second side extending between the first end and the second end, wherein the plurality of couplers includes at least three couplers longitudinally spaced apart from one another along each of the first side and the second side.

28. An offshore fluid cargo handling facility, include: Offshore platforms for handling fluid cargoes; a floating storage vessel deployably moored in the vicinity of the offshore platform via a plurality of deployable mooring lines, the floating storage vessel comprising a hull extending along a longitudinal axis, the hull having a bow end and a stern end, an elongated extension at each of the bow end and the stern end projecting away from the hull to be parallel to the longitudinal axis, each extension having a first elongated side and a second elongated side, the first elongated side and the second elongated side having at least three couplers longitudinally spaced from each other along each elongated side, wherein one of the plurality of deployable mooring lines is attached to each coupler; one or more aerial fluid cargo hoses extending between the offshore platform and the floating storage vessel; A fluid cargo ship having a bow end and a stern end and moored to the floating storage vessel such that the bow end and the stern end of the fluid cargo ship are spaced apart from the deployed mooring lines of the floating storage vessel.

29. An offshore fluid cargo handling facility according to claim 28, wherein the fluid cargo ship has a cargo ship length defined between the bow end and the stern end of the fluid cargo ship, and the floating storage vessel has a storage vessel length defined between the bow end and the stern end of the floating storage vessel, wherein the cargo ship length and the storage vessel length are approximately the same.

30. An offshore fluid cargo handling facility according to claim 28 or claim 29, wherein the fluid cargo ship has a cargo ship length defined between the bow end and the stern end of the fluid cargo ship, and the floating storage vessel has a storage vessel length defined between the bow end and the stern end of the floating storage vessel, wherein the cargo ship length is longer than the storage vessel length.

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