Page 311 - Hydrocarbon Exploration and Production Second Edition

298 Facilities

tank
storm
drain

bund wall
foundation

Figure 11.31 Bund wall and drainage arrangements.

further treatment or storage. However, the design and layout of the offshore
facilities are very different from those on land for the following reasons:

(1) A platform has to be installed above sea level before drilling and process facilities
can be placed offshore.
(2) There are no utilities offshore, so all light, water, power and living quarters, etc.
also have to be installed to support operations.
(3) Weight and space restrictions make platform-based storage tanks non-viable, so
alternative storage methods have to be employed.
This section describes the main types of offshore production platform and
satellite development facilities, as well as associated evacuation systems.

11.2.3.1. Offshore platforms
Offshore platforms can be split broadly into two categories: fixed and floating. Fixed
platforms are generally classified by their mechanical construction. There are four
main types:
steel jacket platforms
gravity-based platforms
tension leg platforms (TLPs)
minimum facility systems.

Floating platforms can also be categorised into three main types:
semi-submersible vessels
ship-shaped monohull vessels (such as floating production, storage and offloading
(FPSO))
SPAR platforms.

TLPs may also be considered as a type of floating platform.
Artificial islands could be regarded as platforms but fall somewhere between land
and offshore facilities.
Steel piled jackets are the most common type of platform and are employed in a
wide range of sea conditions, from the comparative calm of the South China Sea to
the hostile Northern North Sea. Steel jackets are used in water depths of up to