June 10, 2010
BP brings in ships for enhanced collection system
BP is now working on enhancing its subsea collection system at the leaking Deepsea Horizon well site (which it prefers to refer to less emotively as the "MC252" well).
The lower marine riser package (LMRP) containment cap, installed on June 3, continues to collect oil and gas flowing from the leaking well and transport them to the Discoverer Enterprise drillship on the surface. In the first 12 hours of June 9 (midnight to noon), approximately 7,920 barrels of oil were collected and 15.7 million cubic feet of natural gas were flared. On June 8, a total of approximately 15,000 barrels of oil were collected and 29.4 million cubic feet of natural gas were flared. That's a good amount of oil, but its easy to see from BP's webcam that essentially the LMRP cap system is somewhat of a Rube Goldberg arrangement that still leaves copious amounts of oil spewing out.
Behind the public relations facade, probably no one is less pleased with the LMRP than the people who put it together and enhancements are in the works. However, nothing is instant, especially when working in water depths of 5,000 ft, and part of what BP is doing is assembling a fleet of specialized vessels to deal with the oil and gas when it reaches the surface.
Elements of the fleet that are currently in place include the Discover Enterprise drillship that is currently collecting oil and flaring gas from the LMRP cap system. Yesterday morning, BP started lightering oil from the drillship to the 110,000 barrel Moran barge Massachusetts.
The first planned addition to the LMRP cap system will use the hoses and manifold that were deployed for the “top kill” operation to take oil and gas from the failed Deepwater Horizon blow-out preventer (BOP) through a separate riser to the Q4000 vessel on the surface, in addition to the LMRP cap system.
The Q4000, which has been involved in the response for some time, is operated by Helix Energy Solutions Group.and was delivered in 2002 by Keppel AmFELS shipyard in Brownsville, Texas. Q4000 also has a unique column-stabilized semi-submersible design that combines dynamically positioned station-keeping with a large deck space, significant deck load capacity and a high transit speed of 12 knots. The vessel provides a stable platform for a wide variety of tasks, including subsea completion, decommissioning and coiled tubing deployment, and was specifically designed for oil well intervention and construction in deepwater.
The second planned addition is intended to provide a more permanent LMRP containment cap system by directing the oil and gas to a new free-floating riser ending approximately 300 feet below sea level. It is then proposed that a flexible hose be attached to a containment vessel. This long-term containment option is designed to permit more effective disconnection and reconnection of the riser to provide the greatest flexibility for operations during a hurricane. It is expected to be implemented in early July.
The ship selected as the containment vessel is the Toisa Pisces. Operated by Sealion Shipping Services of the U.K. and built by Ulstein Verft, Norway, it is a Liberian-flag ship shaped, dynamically positioned Well Test and Servicing Vessel. It is designed to receive process and offload or store hydrocarbons and other reaction products from Well test, cleanup or stimulation operations. Its production train is capable of dealing with 20,000 barrels
per day oil, 32MMSCFD of gas and 2,000 barrels per day water. Oil collected by the Toisa Pisces will be transferred to the shuttle tanker Loch Rannoch. This is a British-flagged, 130,031 dwt, BP operated tanker that usually transports oil produced in its Schiehallion Oil Field located in the Shetland Trough in the North-West Atlantic Ocean.
Toisa Pisces is set to arrive at the spill site around June 19, while Loch Rannoch should arrive June 12-15