U.S. patent application number 10/986069 was filed with the patent office on 2005-06-30 for method of constructing a liquefied natural gas or liquefied petroleum gas terminal.
This patent application is currently assigned to DORIS ENGINEERING. Invention is credited to Pepin-Lehalleur, Jean Francois Marie, Vache, Michel.
Application Number | 20050139595 10/986069 |
Document ID | / |
Family ID | 34508506 |
Filed Date | 2005-06-30 |
United States Patent
Application |
20050139595 |
Kind Code |
A1 |
Pepin-Lehalleur, Jean Francois
Marie ; et al. |
June 30, 2005 |
Method of constructing a liquefied natural gas or liquefied
petroleum gas terminal
Abstract
The method of constructing an LNG or LPG terminal (3) of the
type comprising an external structure (7) and at least one storage
tank (11; 11a, 11b, 11c), which method is characterized in that it
comprises the steps of: constructing said external structure (7),
in parallel and independently, constructing said storage tank (11;
11a, 11b, 11c), when the construction of said external structure
(7) and said storage tank (11; 11a, 11b, 11c) is completed or on
the point of being completed, floating said external structure (7)
and said storage tank (11; 11a, 11b, 11c), floating said storage
tank (11; 11a, 11b, 11c) into said external structure (7), and
fixing said storage tank (11; 11a, 11b, 11c) to the interior of
said external structure (7).
Inventors: |
Pepin-Lehalleur, Jean Francois
Marie; (Paris, FR) ; Vache, Michel; (Combs La
Ville, FR) |
Correspondence
Address: |
STEVENS DAVIS MILLER & MOSHER, LLP
1615 L STREET, NW
SUITE 850
WASHINGTON
DC
20036
US
|
Assignee: |
DORIS ENGINEERING
Paris
FR
|
Family ID: |
34508506 |
Appl. No.: |
10/986069 |
Filed: |
November 12, 2004 |
Current U.S.
Class: |
220/4.13 |
Current CPC
Class: |
B63B 5/14 20130101; F17C
2201/032 20130101; F17C 2260/013 20130101; F17C 2209/221 20130101;
F17C 2270/0105 20130101; F17C 2203/0629 20130101; F17C 2221/035
20130101; F17C 2221/033 20130101; F17C 3/00 20130101; F17C 2205/013
20130101; F17C 2223/0153 20130101; F17C 2203/0619 20130101; B63B
25/16 20130101; F17C 2203/0617 20130101; F17C 2209/228 20130101;
F17C 2270/0123 20130101; F17C 2201/0128 20130101; F17C 2201/052
20130101; B63B 77/00 20200101; F17C 2203/03 20130101; F17C
2203/0636 20130101; F17C 2270/0113 20130101; E02B 17/02 20130101;
F17C 2223/033 20130101; F17C 2205/018 20130101; B63B 35/44
20130101; F17C 2201/0104 20130101; F17C 2201/0157 20130101; F17C
2201/054 20130101 |
Class at
Publication: |
220/004.13 |
International
Class: |
B65D 006/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 17, 2003 |
FR |
0313409 |
Claims
1. Method of constructing an LNG or LPG terminal of the type
comprising an external structure and at least one storage tank,
comprising the steps of: constructing said external structure, in
parallel and independently, constructing said storage tank, when
the construction of said external structure and said storage tank
is completed or on the point of being completed, floating said
external structure and said storage tank, floating said storage
tank into said external structure, and fixing said storage tank to
the interior of said external structure.
2. Method according to claim 1, comprising the further step of
modifying the relative conditions of flotation of said external
structure and said storage tank to enable the fixing of said
storage tank to the interior of said external structure.
3. Method according to either claim 1 or claim 2, wherein said
external structure remains floating.
4. Method according to either claim 1 or claim 2, wherein said
external structure is placed on the seabed.
5. Method according to claim 1, comprising the additional step of
sheltering and enclosing said storage tank inside said external
structure.
6. Method according to claim 5, further comprising the step of
emptying out the seawater inside said external structure to isolate
said storage tank from the marine environment.
7. Method according to claim 1, further comprising the step of
installing equipment on said storage tank during its
construction.
8. External structure of a terminal for implementing a method
according to claim 1, wherein said structure is conformed to be
able to accommodate said storage tank when constructed.
9. External structure according to claim 8, wherein said structure
has a U-shaped cross section.
10. External structure according to claim 8 for implementing a
method according to claim 4, wherein said external structure is of
the gravity type.
11. External structure according to claim 8, wherein said external
structure is formed of a material chosen from the group comprising
concrete, steel, and concrete+steel.
12. External structure according to any claim 8 for implementing a
method according to claim 5, wherein said external structure
comprises closure means.
13. External structure according to claim 12, wherein said closure
means are chosen from the group comprising a sealed caisson and a
door formed from a material chosen from the group comprising a
metal alloy and concrete.
14. External structure according to claim 12, wherein said closure
means comprise sealing means adapted to be disposed between the
walls of said external structure and those of said storage
tank.
15. Storage tank adapted to equip an external structure of a
terminal according to claim 8 for implementing a method according
to claim 1, wherein said storage tank floats and is adapted to be
installed inside said external structure once constructed.
16. Storage tank according to claim 15, wherein said storage tank
has a shape chosen from the group comprising parallelepiped,
cylinder, prism and sphere shapes.
17. Storage tank according to either claim 15 or claim 16, wherein
said storage tank is chosen from the group comprising double-shell
and single-shell metal storage tanks with thermal insulation and
interior membrane, as appropriate to the type of shell
concerned.
18. Storage tank according to either claim 15 or claim 16, wherein
said storage tank comprises equipment chosen from the group
comprising process equipment, utilities and crew's quarters.
19. LNG or LPG terminal, characterized in that it comprises an
external structure according to claim 8 and at least one storage
tank according to either claim 15 or claim 16.
Description
[0001] The present invention relates to a method of constructing a
liquefied natural gas or liquefied petroleum gas terminal, an
external structure and a storage tank for implementing the method,
and a terminal comprising a structure and a storage tank of this
kind.
[0002] Liquefied natural gas (LNG) and liquefied petroleum gas
(LPG) terminals for loading these liquids onto ships (of the
methane tanker type in the case of LNG) or off loading these
liquids from ships for regassification and landing via a pipeline
are known in the art.
[0003] These terminals, which may be of the gravity type (in
shallow water) or floating type (in deep water), typically comprise
an external structure made of concrete and/or steel containing
cylindrical, prismatic or spherical metal storage tanks or membrane
storage tanks.
[0004] These large storage tanks are assembled inside the concrete
structure when the latter is completed or on the point of being
completed.
[0005] The construction time of these terminals is usually
relatively long and a particular object of the present invention is
to provide a solution that significantly reduces the construction
time.
[0006] This object of the invention is achieved with a method of
constructing an LNG or LPG terminal of the type comprising an
external structure and at least one storage tank, which method is
noteworthy in that it comprises the steps of:
[0007] constructing said external structure,
[0008] in parallel and independently, constructing said storage
tank,
[0009] when the construction of said external structure and said
storage tank is completed or on the point of being completed,
floating said external structure and said storage tank,
[0010] floating said storage tank into said external structure,
and
[0011] fixing said storage tank to the interior of said external
structure.
[0012] This method uses flotation of the storage tank as the
transport means, so that the storage tank may be floated into the
external structure of the terminal in one piece, regardless of its
size.
[0013] Using this method, the external structure and the storage
tanks of the terminal may be constructed completely and
simultaneously, which shortens the critical path and therefore the
overall site time.
[0014] Moreover, the method of the invention envisages constructing
the external structure and the storage tanks on separate specialist
sites, which optimizes costs, quality and reliability.
[0015] According to other optional features of the method of the
invention:
[0016] the method comprises the further step of modifying the
relative conditions of flotation of said external structure and
said storage tank to enable the fixing of said storage tank to the
interior of said external structure,
[0017] said external structure remains floating,
[0018] said external structure is placed on the seabed,
[0019] the method comprises the additional step of sheltering and
enclosing said storage tank inside said external structure,
[0020] the method further comprises the step of emptying out the
seawater inside said external structure to isolate said storage
tank from the marine environment,
[0021] the method further comprises the step of installing
equipment on said storage tank during its construction.
[0022] The present invention also relates to an external terminal
structure for implementing the above method that is remarkable in
that it is conformed to be able to accommodate said storage tank
once constructed.
[0023] According to other optional features of this external
structure:
[0024] it has a U-shaped cross section,
[0025] it is of the gravity type,
[0026] it is formed of a material chosen from the group comprising
concrete, steel, and concrete+steel,
[0027] it comprises closure means,
[0028] said closure means are chosen from the group comprising a
sealed caisson and a door formed from a material chosen from the
group comprising a metal alloy and concrete,
[0029] said closure means comprise sealing means adapted to be
disposed between the walls of said external structure and those of
said storage tank.
[0030] The present invention also relates to a storage tank for
equipping the above external terminal structure that is noteworthy
in that it floats and is adapted to be mounted inside said external
structure once constructed.
[0031] According to other optional features of this storage
tank:
[0032] it has a shape chosen from the group comprising
parallelepiped, cylinder, prism and sphere shapes,
[0033] it is chosen from the group comprising double-shell and
single-shell metal storage tanks with thermal insulation and
interior membrane, as appropriate to the type of shell
concerned,
[0034] it comprises equipment chosen from the group comprising
process equipment, utilities and crew's quarters.
[0035] The present invention also relates to an LNG or LPG terminal
noteworthy in that it comprises the above external structure and
one or more of the above storage tanks.
[0036] Other features and advantages of the present invention will
become apparent in the light of the following description and from
examining the appended drawing, in which:
[0037] FIG. 1 is a sectional view of a ship alongside an LNG/LPG
terminal of the invention,
[0038] FIG. 2 is a plan view of the entities shown in FIG. 1,
and
[0039] FIG. 3 is a view analogous to that of FIG. 2 including a
variant of the terminal according to the invention.
[0040] FIGS. 1 and 2 show a ship 1 such as a methane tanker
alongside a terminal 3 of the invention.
[0041] Pipes 5 connecting the ship 1 to the terminal 3 transport
fluids such as LNG or LPG from one of these entities to the
other.
[0042] In the example represented in FIGS. 1 and 2, the terminal 3
comprises a gravity type external structure 7 formed of concrete,
for example, and resting on the seabed 9.
[0043] Inside this external structure, which has a U-shaped section
open at the top, as may be seen in FIG. 1, is a metal storage tank
11 of substantially parallelepiped shape complementary to the
cavity defined by the external structure 7.
[0044] The metal storage tank 11 rests on the bottom of the
external structure 7 through appropriate mechanical means 13
(welds, nut and bolt fasteners, tie-rods, etc.).
[0045] The metal storage tank 11 has on top equipment 15 that may
comprise process equipment, utilities (networks of pipes, etc.) and
crew's quarters.
[0046] In the example represented in FIGS. 1 and 2, any seawater in
the cavity defined by the external structure 7 has been emptied
out, for example pumped out.
[0047] Where applicable, this cavity is isolated from the seawater
by means that may comprise seals 17 disposed between the interior
walls of the cavity and the storage tank 11 or a watertight steel
or concrete caisson 19.
[0048] The metal storage tank 11 is of the double-shell or
single-shell type with thermal insulation and an interior membrane
according to the type of shell selected.
[0049] Moreover, this storage tank is designed to float.
[0050] In the variant represented in FIG. 3, the single storage
tank 11 is replaced by three substantially cylindrical storage
tanks 11a, 11b, 11c disposed inside the cavity defined by the
external structure 7.
[0051] It will also be noted that in this variant the closure
caisson 19 is sufficiently thick to receive the equipment 15.
[0052] It will further be noted that the seals 17 are disposed
between a mobile door 21 and the internal walls of the structure
7.
[0053] The terminal 3 that has just been described is constructed
as follows.
[0054] The following account refers to the variant represented in
FIGS. 1 and 2, it being understood that the method of constructing
the terminal represented in FIG. 3 is similar in all respects.
[0055] The external structure 7 and the storage tank 11 are
constructed in parallel and independently, where applicable on
separate sites.
[0056] When the construction of the external structure 7 is
completed, it is floated to the operating site, where it either
remains floating or is ballasted so that it rests on the seabed
9.
[0057] When the construction of the tank 11 is sufficiently far
advanced for the storage tank to float, it is also floated and
moved (for example by means of a tug) into the cavity defined by
the external structure 7.
[0058] When the storage tank is inside the cavity, it is placed on
the bottom of the cavity by ballasting the storage tank and/or
deballasting the external structure 7, after which the storage tank
is fixed to the bottom of the cavity using appropriate mechanical
means 13.
[0059] When the storage tank 11 is inside the structure 7, the
cavity defined by the structure may be isolated by means of the
seals 17 and/or the caisson 19 and/or the door 21.
[0060] The water between the storage tank and the internal walls of
the structure 7 may then advantageously be emptied out (if
necessary).
[0061] The connections may then be made between the installations
on the external structure 7 and the equipment 15 on the storage
tank 11.
[0062] As is clear from the foregoing description, the construction
of the external structure 7 and that of the storage tanks 11, 11a,
11b, 11c may be effected in parallel and totally independently,
where applicable on separate specialist sites.
[0063] This shortens the critical path and therefore the overall
time on site for the construction of the terminal 3.
[0064] Furthermore, if separate specialist sites are used for the
construction of the external structure 7 and the storage tanks,
optimum costs, quality and reliability may be achieved.
[0065] It will also be noted that physically dissociating the
external structure 7 and the storage tanks in the terminal of the
invention circumvents constraints regarding the external structure
7 specific to the storage of liquids such as LNG or LPG.
[0066] It will further be noted that the solution consisting in
emptying out the seawater in the cavity defined by the external
structure 7 would seem to be preferable in that it enables easy
maintenance of the storage tanks and the detection and repair of
leaks, as well as reducing the number and/or the size of the
mechanical fixing means 13.
[0067] Of course, the present invention is not restricted to the
embodiments described hereinabove by way of illustrative and
nonlimiting example.
[0068] For example, the external structure 7 need not be of the
gravity type, i.e. of the type resting on the seabed.
[0069] In very deep waters, applying the present invention to an
FPSO type floating external structure 7 may be envisaged.
[0070] Furthermore, the storage tanks disposed inside the cavity
defined by the external structure of the terminal could be of any
type and any shape other than those described hereinabove.
[0071] For example, the storage tanks could be spherical or
prismatic.
* * * * *