Subsea field architecture
Subsea field architecture for production systems are generally arranged as shown in figure to the right. Some subsea production systems are used to extend the reach of existing platforms. For example, the geometry and depth of a reservoir may be such that a small section cannot be reached easily from the platform using conventional directional drilling techniques or horizontal wells, in which case, a subsea development via tie-back can be an economical solution.
Impact of water depth
Water depth can also impact subsea field development. For the shallower water depths, limitations on subsea development can result from the height of the subsea structures. Christmas trees and other structures cannot be installed in water depths of less than 30 m (100 ft). For subsea development in water depths less than 30 m (100 ft), jacket platforms consisting of dry trees can be used.
Wet tree benefit
The goal of subsea field development is to safely maximize economic gain using the most reliable, safe, and cost-effective solution available at the time. Even though wet well systems are still relatively expensive, their attraction in reducing overall capital expenditures has already been made clear.
Subsea tie-backs are becoming popular in the development of new oil and gas reserves in the 21st century. With larger oil and gas discoveries becoming less common, attention has turned to previously untapped, less economically viable discoveries.
Field development considerations
In subsea field development, the following issues should be considered:
- Deepwater or shallow-water development;
- Dry tree or wet tree;
- Stand alone or tie-back development;
- Hydraulic and chemical units;
- Subsea processing;
- Artificial lift methods;
- Facility configurations (i.e., template, well cluster, satellite wells,manifolds).
- Subsea umbilical
- Subsea manifold
- Subsea production riser
- Deepwater drilling
- Subsea production system
- Subsea Engineering Handbook by Yong Bai and Qiang Bai, Publication Date: January 27, 2012 | ISBN-10: 0123978041 | ISBN-13: 978-0123978042 | Edition: 1