Oil flow strains the system

Schlumberger

An artist’s conception shows atomized oil being burned off from an EverGreen smokeless burner — a process that will be employed in the Gulf of Mexico as soon as next week.

How much oil is being lost every day in the Gulf of Mexico spill? That’s one of the contentious issues surrounding the disaster, but another issue has to do with how much can be captured.

Two weeks ago, BP’s medium-term strategy was to seal off the oil leak rather than suck up the leaking oil. The company pumped in thousands of gallons of heavy mud, hoping to overwhelm the upwelling oil and gas. Then the top-kill operation stopped, and BP switched back to the strategy of capturing as much of the leaking oil as possible.

Why the switch? Outside experts have suggested that the top-kill effort was leading to a "doomsday scenario," in which the pressure buildup ruptures the cement linings and rock layers surrounding the well, hundreds or thousands of feet beneath the seafloor. Such an underground blowout could cause oil to seep out uncontrollably from multiple fissures, which would be a nightmare for containment efforts. Some reports raise the prospect that we’re already close to that situation. The Washington Post, for example, quoted an unnamed BP official as saying "we discovered things that were broken in the subsurface" during the top-kill attempt.

BP spokesman Jon Pack told me today that such concerns were indeed part of the reason for turning away from the top-kill strategy. "The possibility of an underground blowout – that could be a result if we were to carry on doing that," he said. But the chief concern was that experts simply couldn’t predict the effect of putting extra pressure on the well, he said.

"Because we don’t have enough accurate information about what was going on in that wellbore, the safest thing to do is move away from that and go to containment," Pack said.

Huge amounts of oil to be burned
That’s why BP sheared off the top of the well pipe, and then attached a cap with a hose attached to bring up the leaking oil. Now about 15,000 barrels (630,000 gallons) of oil are being brought up to the surface every day. That oil is being transferred from the Discoverer Enterprise drilling ship to a barge, which will take it to an onshore terminal for processing. More ships are converging on the site to help with the transfer operation, Upstream Online reports.

But the current containment system can’t capture all the oil, as anyone who has looked at the live video feed from the oil-leak site knows all too well. At best, the system can bring up and process only about 18,000 barrels (750,000 gallons) daily. To collect more oil, BP and its partners are retrofitting the plumbing that was used for the top kill to bring up as much as 10,000 barrels (420,000 gallons) more every day. The base of operations for this second system will be the Q4000 drilling rig, which was used earlier for the top-kill operation.

The only problem is that there’s no capacity available for processing that extra oil on the Q4000. Instead, the oil will be atomized and burned off right at the site, using an imposing piece of equipment known as the EverGreen Burner. Its manufacturer, Schlumberger Limited, calls the EverGreen an "environmentally friendly" burner that is fallout-free and smokeless. But if it works anything like what you see in the artist’s conception above, the EverGreen should put on quite a show.

Yet another Q4000-style system could be brought to bear by the end of the month, the Coast Guard says.

Running the numbers
Burning off hundreds of thousands of gallons of oil a day may seem like a colossal waste, but BP’s Pack told me that "it would take much longer" to bring in the equipment required for processing that much crude oil. The current containment cap and the Q4000’s capture-and-burn system are considered mere stopgaps, to be used while BP builds a more permanent floating-riser oil-collection system for hurricane season. That system should be ready sometime next month.

The charts in this PDF file show all the options for oil collection. If you tally up the numbers released by BP as well as the Coast Guard, you come up with a daily capture capacity of 28,000 barrels (1.2 million gallons) by next week, 38,000 barrels (1.6 gallons) by the end of the month, and 50,000 barrels (2.1 million gallons) by the end of July. That should cover even the high side of the estimates for daily flow from the oil leak. And the permanent fix may come in August, when BP is expected to finish drilling its relief wells and kill the well for good.

At least that’s the plan. Over the past 53 days, we’ve repeatedly seen that the best-laid plans to end the Gulf disaster have often gone awry. Who knows what the next 53 days will bring? Feel free to weigh in with your comments below.

Update for 3 p.m. ET June 12: The plan to burn off hundreds of thousands of gallons of oil every day is sparking environmental concerns. The company that makes the oil-burning equipment may say the process is "environmentally friendly," but a McClatchy Newspapers report quotes health experts and environmental advocates as saying the operation could expose workers in the area to additional toxins. "It seems like a no-brainer that you wouldn’t want to do this," Diane Bailey, a senior scientist with the Natural Resources Defense Council, is quoted as saying.

Meanwhile, the Coast Guard is expressing unhappiness with the pace of BP’s efforts to deal with the additional oil that can be brought up. Rear Adm. James Watson sent a letter to company executives on Friday saying they had 48 hours to come up with a better plan that can be implemented more quickly.

Update for 2:40 p.m. ET June 14: BP has given federal authorities a plan to raise its oil capture rate to as much as 53,000 barrels of oil a day by the end of June. Details are scant, but it sounds as if the plan would phase in the use of the floating-riser oil-collection system earlier than previously scheduled, and also hustle up the arrival of more production facilities at the oil-leak site.

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