How to cope with Gulf oil glitches



Today's temporary loss of a line that has been collecting millions of gallons of leaking oil in the Gulf of Mexico hints at the shape of gusher glitches to come.

This time, the line and a containment cap were taken off the wellhead because of a pressure hiccup, reportedly due to an accident involving a remotely operated vehicle. Hours after the cap was detached, the BP oil company put it back over the leak. But BP might well have to repeat the exercise as hurricane season continues.

For more than two weeks, the containment cap has served as the most successful collection point for the oil that has been leaking from BP's broken well since April 20's fatal oil-rig explosion and sinking. The cap system has saved more than 200,000 barrels (8.4 million gallons) of oil so far, at a rate of up to 16,000 barrels (672,000 gallons) a day. Another 10,000 barrels (420,000 gallons) are being captured and burned off every day by a different collection system hooked up to the well's broken blowout preventer.

The source of the problem
So when the cap containment system had to be detached today, that made quite a dent in the oil-sucking operation. Coast Guard Adm. Thad Allen, the point man for the federal oil-spill response, explained during today's news briefing that the cap was removed after workers "noticed there was some kind of a gas rising through the vent that carries the warm water down that prohibits hydrates from forming." Hydrate crystals, which form from water and methane at a certain pressure and temperature, are what foiled the very first efforts to contain the oil flow - so BP wanted to make sure that didn't happen again.

Allen said the glitch was apparently caused by "a remotely operated vehicle that ... bumped into one of those vents that allows the excess oil to come out." When the vent was closed, the pressure built up, causing gas to go the wrong way. As of this afternoon, BP double-checked the system to make sure it was safe to reattach the cap and return to capturing oil.

Was this a remotely operated screw-up? Actually, the way Allen looks at it, this sort of thing is to be expected as the operation proceeds. He pointed out that there's been only one other ROV misstep, made during the early stages of the response to the gulf disaster. "I think the fact that we've had two bumps that have had some kind of a consequence associated with them in the 60-plus days [of the] response is a pretty good record. It's never going to be risk-free out there, and we need to watch it very closely," he told journalists.

The moderators of the Oil Drum discussion forum speculate that an ROV may not have caused the bump at all, but that it was merely a precipitation plug-up that will happen periodically during the oil-capture operation. If that's the case, bringing up the cap and clearing out the lines will have to become part of the maintenance schedule.

More complications ahead
The pace of operations is likely to get even more intense in a couple of weeks, when as many as four oil-capturing operations are to be conducted simultaneously. That will raise the likelihood of ROVs getting in each other's way, and it will take expert choreography to avoid more frequent bumps or plug-ups.

Another complication has to do with hurricane season. So far, the weather has been mostly favorable for the oil-spill response. There's a weather disturbance brewing in the Caribbean, however, and the National Hurricane Center is predicting a 30 percent chance that the disturbance will turn into a tropical cyclone within 48 hours. If a serious storm threatens the oil-spill area, the response team will need about six or seven days to pack up and evacuate.

During the evacuation, every drop of oil - an amount currently estimated at 35,000 to 60,000 barrels (1.5 million to 2.5 million gallons) a day - would be going directly into the Gulf. It would be like today's capless situation, only worse. "The principle is the same. We would detach and move out," BP spokesman Mark Salt acknowledged.

So as things stand now, a serious storm that looks as if it might blow through the Gulf would kill the recovery operation for as much as 10 days at a time. The spill-response team is working on a Plan B, however. Allen mentioned an ambitious scheme that would involve running an underwater pipeline from the broken well to another oil rig or reservoir. "I believe BP is in discussion with other industry producers that have rigs in the area that might be useful for that," he said. "I don't think they have concluded those [talks] yet."

Allen said such an arrangement could keep the oil under control even during a storm. "This would be one way," he told reporters. "If you are actually connected to another drill site, you would not have to rely on service vessels."

It's one more option in a long list of strategies aimed at stopping up the leak. But is this option ready to put into action? Not yet. BP's Salt said he couldn't discuss the pipeline project, other than to note that "we've always said we're assessing multiple options." So what else does the spill-response team have up its sleeve? What other strategies should they be working on? Feel free to pass along your suggestions as comments below.

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Discuss this post

ground freezing technique using liquid nitrogen is a good idea ,i think .because the liquid nitrogen is a non-inflammable gas so we dont have any fire risk .the liquid nitrogen can freeze water at -250c.the crud oil will easily freeze and it will block the oil spill..already there is a presence of methane ice so it is easy to freeze..we have to insert cooling pipes in the surrounding mud of the bop .so the bop will freeze and it stops the oil flow

http://www.moretrench.com/~moretren/cmsAdmin/uploads/thumb2/Ground_Freezing_003.jpg

http://www.groundfreezing.com/index.html

plzz go through it and think ...if u give more details about oil spill ...i think i can give a better idea

  • 1 vote
Reply#1 - Thu Jun 24, 2010 3:22 AM EDT

Geeeez, this has has turned from a nightmare into a nightmare on ELM Street. Well i guess we should be thinking of a new name for the Gulf of Mexico, how about the Gulf of stupid ideas, no wait the Gulf of crude Oil. oh man, not a laughing matter, but come on, you would think that a company that has so much revenue and resources could do more with this problem. i know companies that only have 15 people working for them that get more things done

  • 1 vote
Reply#3 - Thu Jun 24, 2010 9:20 AM EDT

Thanks for the video and updates, Alan.

It's good to hear that all of the oil only went into the ocean for one day and they're now ready to go forward.

According to Bloomberg. com:

"Forecasters are predicting this year's Atlantic hurricane season, which runs from June 1 through Nov. 30, may be among the most active on record and hamper the U.K. oil company's efforts to plug its leaking well. AccuWeather Inc. forecast at least three storms will move through the region affected by the spill."

http://www.bloomberg.com/news/2010-06-22/tropical-storm-could-pose-formidable-threat-to-bp-oil-clean-up-in-gulf.html

Hopefully things will really turn around, considering that they haven't had much luck so far.

  • 1 vote
Reply#4 - Thu Jun 24, 2010 10:39 AM EDT

I meant to add that if a tropical storm does move through the region, six or seven days to evacuate the site seems like an awfully long time.

    #4.1 - Thu Jun 24, 2010 10:56 AM EDT
    Reply

    Great Job Obama. It is YOUR responsability as are OUR borders.

    You big jackovasaurus.

      Reply#5 - Thu Jun 24, 2010 12:27 PM EDT

      Seriously JBaywatch, what good does Obama bashing serve at this point? He got elected to be the engineer on a train that was already going at full speed. Blaming him for what's going on right now is like blaming the wind for blowing from the south. The deregulating of the oil industry happened WAY before he came to office and the President's "powers" are limited by the red tape called "checks & balances."

      Tell me, what would you do better? It's always easy being an "arm chair quarterback."

      • 1 vote
      #5.1 - Thu Jun 24, 2010 12:37 PM EDT
      Reply

      Again I suggest liquid nitrogen. Freeze everything under the floor of the Gulf in place inside the underground riser. just slowly enough to slowly close off the gushing flow.

      A thermodynamic calculation needs to be done- how much LN2 cooling will it take to stop a flow rate that gives 60,000 barrels per day?

      THEN cement the dang thing.

      • 1 vote
      Reply#6 - Thu Jun 24, 2010 12:37 PM EDT

      Dacarls... could an experiment be done on the surface in some oilfield ?

        Reply#7 - Thu Jun 24, 2010 2:36 PM EDT

        A [previously unconsidered?] Solution: Drill into the Exposed Riser to Divert and Contain Leakage......

        Consider a 3/4" garden hose with water exiting at full pressure.

        End flow will be relieved by tapping into the hose along its length (6 holes of 1/8" diameter, each an inch apart, drilled into the hose; or 3 holes of 1/4" diameter, each 2 inches apart, drilled into the hose). Tubing extending from each hole to a containment tank could hold the water drawn off by these new holes which have essentially diverted the flow.

        This exact principle could be used on the leaking riser which, as I understand, is 18" pipe.

        Thus, to relieve flow/pressure spilling from the broken wellhead ---->> 6 holes [with attached piping] of 3" diameter, each a foot apart, drilled into the casing, below the break/cut, of the exposed riser; or 3 holes [with attached piping] of 6" diameter, each 2 feet apart, drilled, below the break/cut, into the casing of the exposed riser

        The result would look something like the pictorial labeled "Representation of shaped charges firing and penetrating the casing, cement and wall," which is the 3rd image encountered as you scroll down the page at <http://www.theoildrum.com/node/6645>, with, of course, appropriate piping at each new outlet.

        Oil from each of these "new wells" is captured as in a standard drilling operation. With pressure and flow now relieved/diverted, the broken/cut end may be easily sealed.

        Drilling into the length of riser already exposed above the seafloor, below the current leak, would be a far simpler and much quicker remedial than drilling a new well through the bedrock and trying to tap into the line where it extends into the oil reservoir.

        - Michael J Coppi, mjcoppi[at]cs.com

          Reply#8 - Fri Jun 25, 2010 11:02 AM EDT
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