U.S. patent application number 12/767653 was filed with the patent office on 2011-03-24 for floating terminal for loading/offloading ships such as methane tankers.
This patent application is currently assigned to DORIS ENGINEERING. Invention is credited to Nathalie DENJEAN, Jean Francois Marie Pepin-Lehalleur, Pierrick Ivan Leon Marie Sauvage.
Application Number | 20110067617 12/767653 |
Document ID | / |
Family ID | 33522927 |
Filed Date | 2011-03-24 |
United States Patent
Application |
20110067617 |
Kind Code |
A1 |
DENJEAN; Nathalie ; et
al. |
March 24, 2011 |
FLOATING TERMINAL FOR LOADING/OFFLOADING SHIPS SUCH AS METHANE
TANKERS
Abstract
A floating terminal for loading/offloading cargo of ships such
as methane tankers comprises an area for mooring ships and a
submerged skirt to damp oscillation of the terminal to attenuate
relative movement of the terminal and ships in the mooring
area.
Inventors: |
DENJEAN; Nathalie; (Paris,
FR) ; Sauvage; Pierrick Ivan Leon Marie; (Paris,
FR) ; Pepin-Lehalleur; Jean Francois Marie; (Paris,
FR) |
Assignee: |
DORIS ENGINEERING
PARIS
FR
|
Family ID: |
33522927 |
Appl. No.: |
12/767653 |
Filed: |
April 26, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10886584 |
Jul 9, 2004 |
|
|
|
12767653 |
|
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|
Current U.S.
Class: |
114/264 |
Current CPC
Class: |
B63B 39/06 20130101;
B63B 35/44 20130101; B63B 27/24 20130101 |
Class at
Publication: |
114/264 |
International
Class: |
B63B 35/44 20060101
B63B035/44; B63B 21/50 20060101 B63B021/50; B63B 21/00 20060101
B63B021/00; B63B 17/00 20060101 B63B017/00; B63B 27/24 20060101
B63B027/24 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 10, 2003 |
FR |
03 08440 |
Claims
1. A floating terminal for loading/offloading cargo of ships, said
terminal including a partially immersed and substantially
horizontally elongated floating caisson comprising: an area for
mooring said ships, a submerged skirt extending over at least a
portion of the length of said caisson to damp oscillations of said
terminal in order to attenuate relative movement of said terminal
and ships in said mooring area, an orientation device that allows
orientation of said terminal properly relative to the swell, the
wind, or the current, so as to protect said ships, and a component
for loading or offloading the cargo of a methane tanker.
2. The floating terminal claimed in claim I, wherein the submerged
skirt is a submerged horizontal skirt.
3. The floating terminal claimed in claim 2, wherein the submerged
skirt comprises two submerged horizontal skirt components extending
over at least a portion of the length of the terminal's lower
portion.
4. The floating terminal claimed in claim I, wherein the submerged
skirt is a submerged vertical skirt.
5. The floating terminal claimed in claim 4, wherein the submerged
skirt comprises two submerged vertical skirt components extending
over at least a portion of the length of the terminal's lower
portion.
6. The floating terminal claimed in claim 1, wherein the submerged
skirt is oriented at an angle between the horizontal and the
vertical and extending over at least a portion of the length of the
terminal's lower portion.
7. The floating terminal claimed in claim 1 wherein said
orientation device comprises a fixed positioning device.
8. The floating terminal claimed in claim 7 wherein said fixed
positioning device comprises a catenary anchoring system.
9. The floating terminal claimed in claim 1 wherein said
orientation device comprises a mobile positioning device.
10. The floating terminal claimed in claim 9 wherein said mobile
positioning device comprises a system chosen from the group
comprising turret systems and articulated arm systems.
11. The floating terminal claimed in claim 9 wherein said
orientation device comprises a displacement device.
12. The floating terminal claimed in claim 11 wherein said
displacement device is chosen from the group comprising thrusters
and tugs.
13. The floating terminal claimed in claim 1 comprising a swell
damping chamber chosen from the group comprising a chamber on the
upstream side of said floating terminal relative to the direction
of the swell and a chamber on the downstream side in that
direction.
14. The floating terminal claimed in claim 13 wherein said damping
chamber is of the perforated wall type.
15. The floating terminal claimed in claim 1 comprising a component
for storing said cargo.
16. The floating terminal claimed in claim 1 comprising a plant
chosen from the group comprising lines and risers for
importing/exporting said cargo, loading/offloading arms for said
cargo, a device for treating said cargo, crew quarters, maintenance
areas, and control area.
17. The floating terminal claimed in claim 1 constructed from a
material chosen from the group comprising steel, reinforced
concrete, and prestressed concrete.
18. A floating terminal for loading/offloading liquefied natural
gas (LNG) from an LNG carrier, said terminal including a partially
immersed and substantially horizontally elongated floating caisson
comprising: a mooring arrangement for mooring, said LNG carrier in
a side-by-side arrangement with the caisson, a submerged skirt
extending over at least a portion of the length of said caisson to
damp oscillations of said terminal in order to attenuate relative
movement of said terminal and said LNG carrier when the LNG carrier
is moored to said terminal at said mooring area, a terminal mooring
device comprising an orientation device that enables mooring of
said terminal at an orientation transversely relative to at least
one of the swell, the wind, and the current, wherein said mooring
area faces and contacts the open sea and is positioned downstream
of said at least one of the swell, the wind, and the current, so as
to protect said LNG carrier when the LNG carrier is moored to said
terminal at said mooring area, wherein the orientation device
comprises an internal turret adaptable to be connected to the
seabed, such that the internal turret is positioned between a bow
and a stern of the floating terminal, an LNG storage means for
storing the LNG to be off-loaded from or loaded onto the LNG
carrier, and LNG loading/offloading arms for offloading LNG from
the LNG carrier for storage in the storage means and for loading
LNG from the storage means onto the LNG carrier.
Description
[0001] This is a continuation application of application Ser. No.
10/886,584 filed Jul. 9, 2004, which is based on French Application
No. 03 08440 filed Jul. 10, 2003, the entire contents of each of
which are incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a floating terminal for
loading/offloading ships such as methane tankers.
[0004] 2. Description of the Prior Art
[0005] Floating terminals for offshore mooring of ships such as
methane tankers are known in the art.
[0006] These floating terminals are used to load/offload, and
sometimes to store, the cargo of these ships (generally liquefied
natural gas or liquefied petroleum gas) using loading/offloading
arms.
[0007] Floating terminals avoid these ships having to enter ports
and therefore eliminate the problems of space and safety that are
inherent to the size and the nature, respectively, of the cargo of
these ships.
[0008] To carry out loading/offloading operations, a ship must moor
alongside the quay of a floating terminal, the loading/offloading
manifolds or valves of the ship being generally disposed half way
along its length.
[0009] Until now, this kind of mooring could be envisaged only
under relatively calm sea conditions, to limit relative movement of
the floating terminal and the ship and thus to carry out the
loading/offloading operations under acceptable safety conditions.
Limitation of relative movement of the floating terminal and the
ship is also necessary when the floating terminal is adapted to
process hydrocarbons.
[0010] As a result of this, a floating terminal has in fact been
available only intermittently, which has wasted a lot of time and
therefore seriously compromised the return on the investment in the
system.
[0011] An object of the present invention is to provide a floating
terminal that in particular avoids this major drawback.
SUMMARY OF THE INVENTION
[0012] This object of the invention is achieved with a floating
terminal for loading/offloading cargo of ships such as methane
tankers, the terminal comprising an area for mooring ships and
submerged skirt means disposed to damp oscillation of the terminal
in order to attenuate relative movement of the terminal and ships
in the mooring area.
[0013] Because of the skirts for damping oscillation of the
floating terminal, relative movement of the terminal and the ship
may be significantly reduced throughout mooring operations and
during loading/offloading the cargo of the ships.
[0014] Thus the floating terminal many be used even when sea
conditions are bad, which makes the terminal more profitable than
in the prior art.
[0015] According to other features of the terminal of the
invention:
[0016] the floating terminal comprises a submerged horizontal
skirt;
[0017] the floating terminal comprises two submerged horizontal
skirts extending over at least a portion of the length of its lower
portion;
[0018] the floating terminal comprises a submerged vertical
skirt;
[0019] the floating terminal comprises two submerged vertical
skirts extending over at least a portion of the length of its lower
portion;
[0020] the floating terminal comprises a skirt oriented at an angle
between the horizontal and the vertical and extending over at least
a portion of the length of its lower portion;
[0021] the floating terminal comprises means for orienting the
floating terminal relative to the swell, the wind, and the
current;
[0022] the orientation means comprise fixed positioning means;
[0023] the fixed positioning means comprise a catenary anchoring
system;
[0024] the orientation means comprise mobile positioning means;
[0025] the mobile positioning means comprise a system chosen from
the group comprising turret systems and articulated arm
systems;
[0026] the orientation means comprise displacement means;
[0027] the displacement means are chosen from the group comprising
thrusters and tugs;
[0028] the floating terminal comprises a swell damping chamber
chosen from the group comprising chambers on the upstream side of
the floating terminal relative to the direction of the swell and
chambers on the downstream side in that direction;
[0029] the damping chamber is of the perforated wall type;
[0030] the floating terminal comprises means for storing the
cargo;
[0031] the floating terminal comprises plant chosen from the group
comprising lines and risers for importing/exporting the cargo,
loading/offloading arms for the cargo, means for treating the
cargo, crew quarters, maintenance areas, and control areas; and
[0032] the floating terminal is constructed from a material chosen
from the group comprising steel, reinforced concrete, and
prestressed concrete.
[0033] Other features and advantages of the invention will become
apparent on reading the following description and examining the
appended drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] FIGS. 1 and 2 are plan views of a ship moored to a terminal
according to the invention connected to the sea bed by two variants
of a positioning system.
[0035] FIGS. 3 to 8 are views along the shorter side of six
variants of a terminal according to the invention.
[0036] FIG. 9 is a view along the longer side of a further variant
of a terminal according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] Refer now to FIG, 1, which represents a floating terminal 1
essentially formed of a floating caisson 3 moored to the sea bed by
fixed positioning means that may comprise a catenary anchorage
system 5a to 5d.
[0038] The floating caisson 3 may he made of steel and/or
reinforced concrete and/or prestressed concrete.
[0039] It may support diverse plant, such as loading arms 7a, 7b,
means for processing the cargo offloaded from or to be loaded onto
the ships, crew quarters, maintenance and control areas (not
shown), etc.
[0040] FIG. 1 also represents a ship 9 moored to the floating
terminal 1 by any appropriate means such as hawsers 11a to 11c.
[0041] The ship 9 may be a methane tanker, for example, for
transporting liquefied natural gas (LNG) or liquefied petroleum gas
(LPG).
[0042] In this case, the processing means supported by the floating
caisson 3 may comprise plant for liquefying/gasifying the cargo of
the ship 9.
[0043] The caisson 3 comprises storage means (not shown) for
storing the cargo offloaded from or to be loaded onto the ship
9.
[0044] It will be noted that the orientation of the floating
terminal Ito the prevalent direction D of the swell protects the
ship 9 from the swell.
[0045] Refer now to FIG. 2, which represents a variant in which the
floating terminal 1 is connected to the seabed by a turret 13 known
in the art and about which the caisson may pivot in a horizontal
plane.
[0046] Instead, the turret 13 may be replaced by a soft yoke, i.e.
an articulated arm mounted on a jacket (metal truss structure)
anchorage system (this variant is not shown).
[0047] These two variants constitute means for orienting the
terminal 1 appropriately relative to the direction D of the swell
and relative to the directions of the wind and the current.
[0048] In this case, displacement means 14 such as thrusters or
tugs may be envisaged for modifying the orientation of the caisson
3 by causing it to pivot about the vertical axis of the turret 13
or the soft yoke (articulated arm).
[0049] It will be noted that FIGS. 1 and 2 show loading/offloading
arms 7a, 7b that are disposed substantially halfway along the
length of the floating caisson 3.
[0050] This substantially corresponds to the position of the
loading/offloading manifolds (valves) of methane tanker type ships,
which are generally situated halfway along their length.
[0051] Refer now to FIG. 3, in which it is seen that the immersed
portion of the floating caisson 3 comprises horizontal skirts 15a,
15b extending over at least a portion of its length.
[0052] The variant represented in FIG. 4 differs from that from the
FIG. 3 variant in that the skirts 17a, 17b are substantially
vertical.
[0053] In the variant represented in FIG. 5, the caisson 3 is
equipped with horizontal skirts 15a, 15b and with vertical skirts
17a, 17b.
[0054] In another variant, not shown, the floating caisson 3 could
be provided with skirts oriented at an angle between the horizontal
and the vertical.
[0055] Refer now to FIG. 6, in which it is seen that the floating
caisson 3 may be provided with a damping chamber 19 disposed on the
side of the caisson on which the swell impinges, i.e. on the
upstream side of the floating caisson 3 relative to the direction D
of the swell.
[0056] A damping chamber of this kind is known in the art, and in
particular from French patent FR 2 693 216, and may typically
comprise an exterior wall 21 provided with a plurality of regularly
distributed orifices 23, as shown in FIG. 9.
[0057] This kind of wall is sometimes called a Jarlan wall.
[0058] In the variant represented in FIG. 7, the damping chamber 19
is on the downstream side of the floating caisson 3 relative to the
direction D of the swell.
[0059] In the variant represented in FIG. 8, the floating caisson 3
comprises an upstream damping chamber 19a and a downstream damping
chamber 19b.
[0060] The mode of operation and the advantages of the terminal
according to the invention follow directly from the foregoing
description.
[0061] The ship 9 wishing to load or offload cargo moors alongside
the quay of the floating terminal 3 on the side sheltered from the
swell D (see FIGS. 1 and 2).
[0062] The horizontal skirts 15a, 15b damp vertical oscillation of
the terminal.
[0063] The vertical skirts 17a, 17b damp horizontal oscillation of
the terminal.
[0064] Furthermore, the combination of these skirts limits the
coefficient of transmission of swell between the upstream and
downstream sides of the terminal (the terms "upstream" and
"downstream" being understood as meaning with respect to the
direction of the swell).
[0065] In the variant represented in FIG. 2, the orientation of the
floating terminal 1 may be modified at will to optimize the
protection from the swell D, from the wind and from the current.
The combination of submerged skirts and means for controlling the
orientation of the terminal is particularly advantageous.
[0066] All this radically reduces relative movement of the terminal
and the ship 9 when the ship is moving alongside and being moored
to the caisson 3 and while loading/offloading the cargo of the ship
by means of the arms 7a, 7b.
[0067] Thus the floating terminal may be used even if the sea
conditions are bad, which makes this terminal more profitable than
in the prior art.
[0068] The cargo of the ship 9 may be stored and/or converted on
the terminal 1 or be sent directly from ship to land or vice-versa
by means of appropriate pipes.
[0069] Of course, the present invention is not limited to the
embodiment described and shown, which is provided by way of
illustrative and nonlimiting example.
* * * * *