BP has started up a second system to siphon oil from its gushing Gulf of Mexico leak, a day after the US government massively increased its estimate of the flow rate from the ruptured well.
BP also said its containment cap system installed at the leak on June 3 collected 10,440 barrels of oil yesterday, lower than on previous days and reflecting a five-hour shutdown after a lightning strike ignited a fire at a derrick on the drillship collecting the oil.
The leak gushed unchecked during the shutdown, the company said.
The cap system, which follows a string of unsuccessful efforts by BP to contain the spill, had been collecting more than 15,000 barrels a day since June 8, with a high of 15,800 barrels on June 9, according to BP figures.
Overall, the cap system has collected 160,400 barrels of oil since it was installed on June 3, according to BP. A live video feed on BP's website shows an undetermined amount of oil continues to leak out from under the cap and from three open vents on top of it.
The cap system's success is dwarfed by the overall spill since a rig explosion on April 20 that triggered the well rupture and the worst oil spill in US history.
Yesterday, a team of US scientists raised their high-end estimate of the amount of crude oil flowing from the well by 50% to between 35,000 and 60,000 barrels per day (5.56 million litres to 9.5 million litres) a day.
The estimated range includes the oil being captured.
That team initially estimated the leak to range from 12,000 to 19,000 barrels per day, and last week increased that to 20,000 to 40,000 barrels per day.
The cap system can handle up to 18,000 barrels a day of oil, which is the maximum processing capacity of Transocean's drillship collecting the crude 1.6 km above the leak, BP said.
The second system is intended to increase overall collection capacity to 28,000 barrels a day, BP said.
Its addition is one of several enhancements and changes to eventually push collection capacity to 80,000 barrels a day by mid-July, according to BP's plan submitted to the US Coast Guard on Monday.
The company would not say how much oil the new system has collected since it started up.
All oil collected by the second system will be channeled to a service rig at the water's surface, the Helix Q4000. That oil will be burned off because the rig has no storage or processing capability.
"When measurements are available for volumes of oil and gas being flared by the Q4000, this information will be added to the updates on BP's website," the company said.
The Q4000 system is reusing seabed equipment installed in May for BP's failed "top kill" effort to smother and plug the leak, the company said.
The top kill involved pumping heavy drilling fluid through hoses connected to a failed blowout preventer and into the well to try to stop the leak. Now that same system of hoses and pipes are pulling oil and gas from the well to the Q4000 to be burned off, according to BP.
The company is drilling relief wells that it hopes will definitively halt the spill in August.