The containment cap placed on the leaking wellhead of the Deepwater Horizon succeeded in diverting 6,000 barrels of oil to a ship in the first 24 hours–that’s a quarter to a half of the oil estimated to be flowing from the well, Coast Guard Commander Thad Allen announced moments ago in a teleconference with reporters.
That number is expected to increase as BP lowers pressure inside the wellhead by drawing oil to the surface at an increasing rate.
The ship above the well, dubbed the Discover Enterprise, can reportedly process up to 15,000 barrels per day. The U.S. has estimated 12,000 to 25,000 barrels per day are leaking from the wellhead.
“What’s happening is they are increasing production rates, and they’re doing it gradually to avoid the formation of hydrates. The goal is to achieve maximum production on the vessel overhead,” Allen said.
Oil continues to leak from the seal between the cap and the severed wellhead, and that leak will probably continue until BP finally seals the well beneath the earth by injecting slurry into it from a relief well–an event that may not take place until August. That’s because the pressure of the oil inside the cap has to remain higher than the pressure of the surrounding water.
“What you want to do is keep oil in the containment cap and not water, because water produces hydrates,” Allen said.
Methane hydrate crystals foiled an earlier attempt to cap the well by blocking the path of the oil to the surface and making the cap more buoyant.
Vents on the cap, also designed to prevent the formation of hydrates, also remain open, allowing oil to escape from the cap. Those will be gradually closed as the production rate increases on the ship overhead.
The ship measured the 6,000 barrels from midnight Friday morning to midnight Saturday morning, as the process began. The rate of recovery should only accelerate, barring hurricanes and other mishaps. The government is working with a number of estimates of the flow rate of the spill. An official Flow Rate Technical Group used three different methods to estimate the spill at 12,000 to 19,000 barrels per day. Another independent estimate put the rate at 12,000 to 25,000 per day.
The process of siphoning oil to the ship should help officials develop more accurate estimates of the spill rate as well, Allen said.
Related articles by Zemanta
Next post: BP tries to rename oil spill
Previous post: BP lowers cap onto well; oil continues to gush through valves