APNewsBreak: Bubble of Methane Triggered Rig Blast

[Elmore Furth]

Source: Associated Press

THE ASSOCIATED PRESS
Published: May 8, 2010
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Filed at 3:18 a.m. ET

ON THE GULF OF MEXICO (AP) -- The deadly blowout of an oil rig in the Gulf of Mexico was triggered by a bubble of methane gas that escaped from the well and shot up the drill column, expanding quickly as it burst through several seals and barriers before exploding, according to interviews with rig workers conducted during BP's internal investigation.

While the cause of the explosion is still under investigation, the sequence of events described in the interviews provides the most detailed account of the April 20 blast that killed 11 workers and touched off the underwater gusher that has poured more than 3 million gallons of crude into the Gulf.

Portions of the interviews, two written and one taped, were described in detail to an Associated Press reporter by Robert Bea, a University of California Berkeley engineering professor who serves on a National Academy of Engineering panel on oil pipeline safety and worked for BP PLC as a risk assessment consultant during the 1990s. He received them from industry friends seeking his expert opinion.

Based on the interviews, Bea believes that the workers set and then tested a cement seal at the bottom of the well. Then they reduced the pressure in the drill column and attempted to set a second seal below the sea floor. A chemical reaction caused by the setting cement created heat and a gas bubble which destroyed the seal.



Read more: http://www.nytimes.com/aponline/2010/05/08/us/AP-US-Gulf-Oil-Spill.html?ref=news

[tanyev]

1. Oh, the irony.

A group of BP executives were on board the Deepwater Horizon rig celebrating the project's safety record, according to the transcripts. Meanwhile, far below, the rig was being converted from an exploration well to a production well.

The BP executives were injured but survived, according to one account. Nine rig crew on the rig floor and two engineers died.

[Elmore Furth]

3. Federal regulators warned oil rig operators in 2000 about blowout preventers...

but the Interior Department never took steps to address the issue definitively but just took industry assurances that it was on top of the problem. More Bush idiocy coming back to bite us.

http://www.nytimes.com/2010/05/08/us/08agency.html?ref=science

[Igel]

15. Some yes, some no.

The 2004 and 2007, surely.

But unless there was a 1999 presidential election in the US that I wasn't aware of, the 2000 warnings fell on non-Bushy ears.

February 2000 to January 2001. Eleven months isn't a *long* time, but it's often enough.

[NecklyTyler]

2. We hear the estimates of 60000 barrels of oil a day spewing out of the sea floor

But how much Methane is bubbling out at the same time.

Methane is 80 times stronger as a greenhouse gas than CO2

[lonestarnot]

4. We are so fucked.

[FailureToCommunicate]

5. Halliburton SHOULD have learned a lesson from the Timor Sea disaster...

And US regulators should have learned also! (Oh, wait, there aren't any real oil drilling regulators -only cheerleaders and tax collectors!)

link:
<http://en.wikipedia.org/wiki/Montara_oil_spill>

[underpants]

7. The way I read this (was just about to post it) is tht Halliburton is off the hook

I think. I have to admit that I don't know enough about this to really understand what this article says-it is written in a very confusing way.

[alfredo]

10. Methane ice is very unstable. When the concrete sets, it

heats up. If there is methane ice nearby It will expand.

http://marine.usgs.gov/fact-sheets/gas-hydrates/title.html

[underpants]

19. Okay - I was wrong

According to the account he has pieced together, a group of BP executives were on board the Deepwater Horizon rig celebrating the project's safety record while, far below, the exploration well was being converted for oil production.

The workers set and then tested a cement seal at the bottom of the well, he believes, but - as they reduced the pressure in the drill column and attempted to set a second seal below the sea floor - a chemical reaction caused by the setting cement created heat.

That heat converted a pocket of methane crystals into a bubble of compressed gas which grew as it rose up the drill column.

http://www.telegraph.co.uk/finance/newsbysector/energy/oilandgas/7696596/BP-oil-disaster-how-a-deadly-methane-bubble-triggered-explosion.html

[alfredo]

20. That methane could be really dangerous. It could also

power the US for decades.

[FailureToCommunicate]

17. Halliburton was involved in the concrete work as a contractor in both the Montara and Gulf spills

link:

<http://www.nytimes.com/2010/05/03/us/03montara.html>

[underpants]

18. Okay- I was wrong

According to the account he has pieced together, a group of BP executives were on board the Deepwater Horizon rig celebrating the project's safety record while, far below, the exploration well was being converted for oil production.

The workers set and then tested a cement seal at the bottom of the well, he believes, but - as they reduced the pressure in the drill column and attempted to set a second seal below the sea floor - a chemical reaction caused by the setting cement created heat.

That heat converted a pocket of methane crystals into a bubble of compressed gas which grew as it rose up the drill column.

http://www.telegraph.co.uk/finance/newsbysector/energy/oilandgas/7696596/BP-oil-disaster-how-a-deadly-methane-bubble-triggered-explosion.html

[seabeckind]

6. Sorry, gotta problem with this

Gotta call bullshit.

Report comes out a week after the "accident" and blames a mean ole methane cloud. This report written by an independent guy who just happened to work for BP.

(No one could have predicted comes to mind)

My question is: And this cloud formed why? Seems like maybe the methane exploding might have been unavoidable but the creation of the cloud ahead of time ... not so much.

Sorry guys, next ...

<edit> fix fat finger.

[Igel]

16. Some of the earliest reports spoke of gas detectors sounding.

The gas cloud would have formed very quickly. If it's under enough pressure to force its way up from 5k ft down, it's unlikely we're talking about just a cubic meters per minute. IIRC, this was a minute or two before the oil came through.

The gas cloud would then have formed by default if the winds weren't strong enough to disperse it, esp. in nearby partly enclosed areas.

Moreover, CH4 is the most plausible and reasonable excuse for a fire that size, esp. one that's explosive. You usually have to work at least a little to get crude oil to ignite. A spark won't do it. If you get it going, it's not going to explode--it's not volatile enough, even if it's light and has a fair proportion of volatile fractions. A simple oil gusher without natural gas can't account for the initial results in a fairly straightforward way.

However methane's often associated with oil wells, for obvious reasons and has all the right properties to account for the first reports in a fairly brainless way.

[ShockediSay]

8. There was a report on TV last night that South American countries

w/ offshore drilling require remote control shut-offs for just this type of situation.

I believe industry eliminated this kind of requirement in the US

[AlbertCat]

9. Exploding methane....where has that been a problem before? In WV perhaps? Hmmmmm....

Could the lesson be any clearer?

Fossil fuels are for fossils. Burning them is old, tired and obsolete. We've been doing it or 2 centuries now and it's time for something new.


The other common denominator is deregulation.

It's as obvious as an oil slick you can see from space.

[Ian David]

11. 4Chan was saying that days before anyone else was. n/t

[alcibiades_mystery]

12. Halliburton fucked the cement job

There's a big fucking surprise.

:eyes:

[mbperrin]

13. That's the bottom of it. Methane gas, natural gas, all gas is just that,

and if annular pressure had been maintained, no gas could have done anything but stayed right where it should - below the wellhead.

[Barackbaby]

22. How do we know it wasn't a faulty BOP?

[PfcHammer]

14. Definite possibility. I've seen it happen

in my own bathroom after 4 7 layer burritos from Taco Bell. :P

[daleo]

21. Shouldn't the blowout preventer have handled this?

Surely a release of methane is not an unexpected occurrence when drilling for hydrocarbons. It's like blaming gravity for an an airplane crash.

[Lionel Mandrake]

23. How much methane are we talking about?

The methane that didn't burn will eventually drift into the stratosphere and contribute to global warming. Methane is much worse than carbon dioxide in this respect.