American Oil and Gas Reporter - June 2015 - 90

SpecialReport: Offshore & Subsea Technology
LLOG is the operator of Delta House, and along with Blackstone Energy Partners (LLOG's joint venture partner in the Gulf),
is the largest working interest owner of the subsea wells. Project co-owners are Red Willow Offshore, Calypso Exploration,
Deep Gulf Energy II, Houston Energy, and entities managed by
Ridgewood Energy. ArcLight Capital Partners provided construction financing for the $860 million FPS and export pipelines, and
is 51 percent majority owner of the host platform.
Borrowing its name from the fictional fraternity in the 1978
movie Animal House, the project symbolizes LLOG's transition
from a Shelf operator focused primarily on mature, shallow-water properties to becoming one of the largest privately owned deepwater exploration companies in the Gulf, and the top privately
held liquids producer in the United States.
It is LLOG's second major FPS-based development to be
brought on line in the past four years. The first FPS, using an Exmar-designed OPTI-EX™ hull, was installed at the Who Dat Field
in Mississippi Canyon Blocks 503, 504 and 547. As LLOG was
about to bring Who Dat on production in the fall of 2011, it recognized that a number of exploration prospects in its deepwater
Gulf inventory were "hub class," meaning that if drilling was successful, field development might include an FPS.
Standardized FPS Design

While the industry norm is to custom design each FPS to the
needs of a specific discovery, LLOG decided that 15 hub-class
prospects in inventory and a consistent exploration success rate
of 70 percent warranted a change of philosophy. Consequently,

First steel cutting for the Delta House FPS hull occurred in March
2013 at Hyundai Heavy Industries' yard in South Korea. Dockwise's Treasure heavy-lift transport vessel delivered the fabricated hull to Kiewit Offshore Services' yard in Ingleside, Tx., in
May 2014 for integration with the deck. LLOG is operator of Delta
House. Blackstone Energy Partners is LLOG's joint venture partner in the Gulf. Delta House co-owners are Red Willow Offshore,
Calypso Exploration, Deep Gulf Energy II, Houston Energy, and
entities managed by Ridgewood Energy. ArcLight Capital Partners provided financing for the FPS and export pipelines.

90 THE AMERICAN OIL & GAS REPORTER

LLOG set out to implement a "design one, build many" FPS project.
To set the stage for efficient fast-track deepwater developments,
LLOG's goal was to develop a standardized FPS design basis that
would fit the needs of most of its hub-class exploration prospects.
LLOG chose the OPTI design for a number of reasons:
* LLOG prefers a wet tree solution to keep drilling and production operations separate, believing that the benefits of
predrilling and completing wells generally outweigh the dry tree
advantage of lower intervention costs.
* It had success with the OPTI design at the Who Dat project, and choosing any other design would require additional time
to become familiar with the design.
* The design has high flexibility and may be deployed in water depths up to 10,000 feet.
* The design is robust and compliant with the latest windstorm criteria.
* A four-column semisubmersible allows for lower-risk quayside integration compared with other FPS designs that require an
offshore lift.
* The single-deck design facilitates construction and allows
for late deliveries of equipment without affecting the overall schedule (most deepwater facilities use three decks, and each subsequent deck cannot be floated in place until all the major equipment is in place on the previous deck.
* The hull is designed to use less steel and to be easier to fabricate than other hull designs (in fact, Delta House achieved a ratio of payload to hull steel weight of 1.0).
LLOG elected to design the FPS with a nameplate capacity
of 80,000 barrels of oil, 200 million cubic feet of gas, and 40,000
barrels of water a day, with an API oil gravity range of 25-38 degrees and a gas-to-oil ratio range of 750-2,000 cubic feet per barrel. LLOG defines nameplate to exclude standby/redundant equipment. For example, the 80,000 barrels of oil would include three,
40,000 bbl/d pumps so that if one pump was down for maintenance, the facility would still be capable of producing the nameplate capacity.
High run times are expected using the nameplate capacity, and
with peaking capacity of 100,000 bbl/d oil and 240 MMcf/d of
gas, production beyond the nameplate is achievable. The
throughput capacity met the needs of nearly all of LLOG's hubclass prospects, and is the largest capacity that can be achieved
with a single deck lift with existing equipment. LLOG chose to
design for ANSI 1,500 exports for both oil and gas, since doing
so would be adequate for nearly every pipeline in the Gulf.
Superior Economics

LLOG recognized that the facility would be overdesigned for
some of its prospects, but felt the standard design would yield
superior economics. A purpose-built design would slow the schedule and sacrifice cost savings, and would not be proportional to

American Oil and Gas Reporter - June 2015

Table of Contents for the Digital Edition of American Oil and Gas Reporter - June 2015