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; 11 a , 11 b , 11 c ), 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; 11 a, 11 b , 11 c ), when the construction of said external structure ( 7 ) and said storage tank ( 11; 11 a, 11 b , 11 c ) is completed or on the point of being completed, floating said external structure ( 7 ) and said storage tank ( 11; 11 a , 11 b , 11 c ), floating said storage tank ( 11; 11 a , 11 b , 11 c ) into said external structure ( 7 ), and fixing said storage tank ( 11; 11 a, 11 b , 11 c ) to the interior of said external structure ( 7 ).

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.