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The first dedicated FPSO application offshore was by Arco in the Ardjuna

               field  in  the  Java  Sea  offshore  Indonesia  in  1976  (D’Souza  et  al.  1994).

               Interestingly, this was a concrete barge with steel tanks, used to store refrigerated

               liquefied petroleum gas (LPG) moored to a buoy using a rigid arm system in 42.7m

               water  depth.  The  first  tanker-based  single-point  moored  FPSO  facility  for  oil  is

               said to be the Castellon for Shell offshore Spain in 1976. This facility was meant to

               produce  oil  from  a  subsea  completed  well,  some  65  km  offshore  Tarragona.  It

               began operations in 1977, and was designed for a 10-year field life.

                      Compared  to  these  early  days,  floating  production  systems  have  now

               evolved  to  a  mature  technology  that  potentially  opens  up  the  development  of

               offshore oil and gas resources that would be otherwise impossible or uneconomical

               to  tap.  The  technology  now  enables  production  far  beyond  the  water-depth


               constraints  of  fixed-type  offshore  platforms  and  provides  a  flexible  solution  for
               developing short-lived fields with marginal reserves and fields in remote locations


               where installation of a fixed facility would be difficult.
                      Generally ship shaped floaters with provisions for storing and offloading of


               oil simultaneously. They may be designed to weathervane so that they always face
               the weather, minimising roll and heave motions. In benign environments such as


               West Africa and South East Asia, the FPSO may be spread moored to face one

               direction at all times.

                      Some FPSOs for Brazil have been designed to semi-weathervane by using a

               spread  mooring  with  slack  aft  moorings,  giving  the  vessel  the  options  of  some

               limited weat hervaning

                      Oil production is through either flexible risers or riser towers with flexible

               jumpers.  The  motions  of  the  FPSOs  generally  prohibit  the  attachment  of  rigid

               vertical risers or steel catenary risers.

                      The  FPSOs  have  a  large  area  for  setting  a  deck  on  the  top  of  the  hull.

               However,  many  FPSO  hulls  are  conversions  and  the  deck  structure  may  not  be

               designed  to  carry  a  Floating  Offshore  Platfornz  Design  processing  facility.  This
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