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Gulf Gusher Worst Case Scenario
An anonymous reader writes "Here's a listing of several scientific and economic guides for estimating the volume of flow of the leak in the Gulf of Mexico erupting at a rate of somewhere around 1 million barrels per day. A new video released shows the largest hole spewing oil and natural gas from an aperture 5 feet in diameter at a rate of approximately 4 barrels per second. The oil coming up through 5,000 feet of pressurized salt water acts like a fractionating column. What you see on the surface is just around 20% of what is actually underneath the approximate 9,000 square miles of slick on the surface. The natural gas doesn't bubble to the top but gets suspended in the water, depleting the oxygen from the water. BP would not have been celebrating with execs on the rig just prior to the explosion if it had not been capable producing at least 500,000 barrels per day — under control. If the rock gave way due to the out-of-control gushing (or due to a nuke being detonated to contain the leak), it could become a Yellowstone Caldera type event, except from below a mile of sea, with a 1/4-mile opening, with up to 150,000 psi of oil and natural gas behind it, from a reserve nearly as large as the Gulf of Mexico containing trillions of barrels of oil. That would be an Earth extinction event."
Hey, so do I, and I call bullshit fearmongering on the Yellowstone-like caldera unless someone else chimes in.
Populus vult decipi, ergo decipiatur...
"Force shits upon Reason's back." - Poor Richard's Almanac
There aren't 'trillions' of barrels under this particular well. It's not like collapsing this well would cause all the other wells to collapse too. And as far as I know, the likelihood of this deposit collapsing is very, very low; unmeasurably low.
So far, oil isn't even washing up on beaches in any appreciable way. A huge portion of the area is an oxygen-depleted, polluted 'dead zone' anyway because of the Mississippi. Last I checked, only -two- birds had been collected for cleaning. Only about 4% of the gulf is blocked-off from fishing, and the larger fisheries aren't even expecting much damage, they're taking a 'wait and see' stance.
Still, (as of yet) clean beaches and untainted food seem to scare consumers away from vacations and shrimp, not because there's a risk, but because most consumers are total alarmist bozos, just like most career-environmentalists.
"Sometimes, I think Trent just needs a cup of hot chocolate and a blankie." -Tori Amos on Nine Inch Nails
Did you check the actual figures?
5000 BARRELS a day is about 200,000 GALLONS a day. These have been pretty consistently reported in the mainstream media for days.
Both can be true, actually.
Peak oil doesn't mean we've run out or that we're nearly running out. It means we've reached the maximum yearly production. At some point, extracting additional oil becomes incredibly expensive, and our production falls off. After that point, there's still oil, but we can't extract as much as we used to. So, even if we've hit peak oil, there's decades of production left. And if we haven't hit peak oil, there's an additional buffer of several decades. But even in the most optimistic industry estimates, peak oil is happening within the next 50-70 years.
The article seems to be inaccurate in at least one respect, and one comment calls the author on it: It's not a 5-foot diameter pipe. Various sources say it's either 12-inch or 21-inch, but not five feet. One source says the largest riser pipe made is 21-inches in diameter.
[place clever signature here]
The current estimate for total world reserves is just over 1 trillion, so this guy is just a total idiot.
There are 42 gallons, not 55, in a barrel of oil.
Not that it makes it any less of a disaster, but it is the correct number.
Well, lets see...
The Library of Congress contains roughly 1,199 kilometers of books. Assume that each shelf is roughly 30cm by 30cm, you get a volume of roughly 107,910 m3. To fill that volume with barrels of oil...
A barrel of oil is 42 US Gallons, or 0.158987294928 m3. So, you need 6.29 barrels to get 1 m3.
So we should need about 678,753 barrels of oil to constitute one library of congress.
So, at a rate of 4 barrels per second, there is a library of congress worth of oil being dumped into the Gulf about every 47 hours.
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Crude is measured in 42 gallon barrels.
http://en.wikipedia.org/wiki/Barrel_per_day
supports the estimates closer to 1 million barrels per day erupting from this hole BP popped in the ocean floor that contains trillions of barrels of oil and natural gas.
Anyone who starts an article out with a misstatement like that is immediately deemd not credible. If there were "trillions" of bbls of oil at that well (or even in the gulf of Mexico) we would never need to import a drop again and in fact would be the largest holder of oil in the world. S. Arabia has 270 billion bbl proven reserves.
And on a more serious note, based on 4 barrels per second is 12 square kilometers of oil 1 millimeter deep every day.
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Okay, 150,000PSI is 10,444 atmospheres of pressure. Granite has an ultimate compressive strength of around 2775 atmospheres. In other words, at 10K atmospheres, granite would be flowing like water. There's no possible way the oil is coming out at that pressure. And if it was, it sure as heck would be flowing faster than 4 bbl/s. This guy is tossing out some serious BS numbers.
Life, the Universe, and Everything... in my image.
Care to explain how you got those numbers?
At 0.433 psi per foot of water, assuming it’s a constant, 16,000 feet of head is only about 6,925 psi.
If we assume that the ocean floor has about the density of granite (2.7x that of water), then it’s about 5,000 x 0.433 + 11,000 x 0.433 x 2.7, or about 15,025 psi.
Either way it’s nowhere close to the 13,000 psi that you got, although 15,000 psi sounds more like it might be the correct figure and the article was just off by a factor of 10.
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
Geez, calm down already.
Someone doesn't understand hydrolics very well.
Someone doesn't spell hydraulics very well. Did you skip that class in third grade?
Finally, I'm really lazy I admit, but can someone tell me if theres a way to ignore timothy and kdawson stories?
Go to help & preferences. If you use the classic index, click on "authors" and un-check them. If you use the dynamic index, click on "exclusions" and check them.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
Luckily, the coastal waters of the gulf are largely an oceanic dead zone already, so there's not that much left for the oil to kill. Um, yay?
"I guess the moral of the story is, don't paint your airship with rocket fuel." -- Addison Bain
And his math skills need some work (check his pond reference: 400,000 gallons != 1000 barrels) There are an awful lot of things that don't add up in his article.
Sure. Here's a link to a commonly used oil industry graph:
2X the hydrostatic gradient is "about" the most pressure ever encountered in wells. Of course, relying on that could be part of why BP is in the mess it's in, but I suspect the original problem may well have been the hydrates, and/or a cementing problem, as speculated elsewhere in the oil industry press.
Your estimate of water and rock density is fine. It's just that downhole pressure versus formation depth can vary significantly - the total weight of the overburden is NOT translated into actual pressure, since the rock is somewhat solid...
sadly there are always humans who want to eradicate knowledge and they thrive when times are hard.
In any apcalyptic scenario you can be sure there would be people who actively tried to destroy old knowledge.
General fail: proof by hyperbole. LOOK AT THIS HUGE OIL SLICK HOW CAN YOU SAY IT'S 5000 BARRELS A DAY THAT'S CRAZY! is not a persuasive argument.
Specific fail: Pipe is not 5 feet in diameter.
here's a photo of the pipe with a wrench for scale -- BP says the wrench is a foot long. So accounting for perspective, the pipe is a bit more than a foot in diameter. (BP says the outer diameter of the riser pipe was 21" diameter when installed, but it's gotten a bit squished since then.)
Video shows the pipe about half full of oil, so the cross-sectional area of the flow is 1/2 * pi * (7 inches)^2 = 0.05 meters^2.
By following the motion of the blobs and plumes of oil, the flow speed seems to be about 1 meter/second. Flow rate = velocity * area = 0.04 m^3/s, or 0.4 barrels/second.
This is 27,000 barrels per day -- about 5 times BP's estimates, but an order of magnitude less than the article claims.
the Oil Spill Liability Trust Fund, which limits oil companies' total liability in case of an oil spill to $75 million.
It's worth noting this refers to Economic liability - i.e, liability for economic damage done to an area as a result of an oil spill. BP is still on the hook for cleaning up the mess, and that's a price tag without a limit.
Those who can, do. Those who can't, sue.
After the Exxon Valdez accident the Oil Pollution Act was passed that explicitly made the oil company responsible for paying the cleanup costs: http://www.google.com/hostednews/afp/article/ALeqM5ha08OW3ueCMBc6oEsdyoXp9JAGDw
You mean a stack?
Ok, slightly less mathematical and scientific than you. The article says 10,000+ sq miles surface area slick. Assuming this is 1 molecule thick and assume that each molecule is touching each other and atom size of 1 angstrom and average atomic weight of 9 au, we get total volume of 12 million Ga. Again the article claims this is about 20% of total, so we get total of 60 million Ga. this is about 25 times that of the estimate based on 5000 barrels a day.
GE Oil and Gas states:
so I think it's reasonable to assume that the "5 foot" pipe leaking oil is in reality a 18 3/4 inch inner diameter pipe at most if its a piece of broken riser pipe, less if it's the drill pipe (18” and 16” casing strings). I've seen reports that the riser now comes out of the BOP, Blow-out Preventer, goes up for 1,500 feet and is bend back and buried in the sea-floor, so this five foot "pipe" could be the mouth of an Asphalt Volcano forming around the leak, in short the article is at best miss-informed conjector. Also the BP execs were not there to celebrate the well hitting oil, but to give an safety award to the rig for working 7 years without a lost time accident which is much more ironic I think.
Apocalypse Cancelled, Sorry, No Ticket Refunds
Don't forget the pressure of the oil column in the 11,000 foot pipe. At a 900 kg/m^3 density, that's another ~4000 psi you need to add to the 2000 psi water pressure.
Comment removed based on user account deletion
FTA The following article was written by my associate, by Paul Noel with some editing and input from me.
Not the best of credentials there.
The site the profile of Noel is posted on had an article about "Free energy" and "former CIA directors" on the front page, so there may be a signal to noise problem there as well.
Apocalypse Cancelled, Sorry, No Ticket Refunds
Is the DOE good enough? Probably not, but whatever:
http://www.eia.doe.gov/emeu/international/reserves.html
Actually, not so fast. Roughly 6% of people who ever lived are alive today...
http://www.wolframalpha.com/input/?i=how+many+people+ever+lived+on+earth
Leaving 94% dead!
When you hear hoofbeats, think horses, not zebras
All nuclear plants are critical. That is how they goddamned work. Once again, another anti-nuke wacko proves he has no fucking idea what he is talking about, prefering to throw around "scary" words instead of actually researching shit. I swear to god, it's like knowledge is actually taboo to you people.
"linux is just DOS with a UNIX like syntax" -- Galactic Dominator (944134)
Some comments on your analysis:
(1) TD for the well is at 18369 ft MSL.
(2) Reservoir pressure should be more like 18369 * 0.433 = 7954 psia with a normal hydrostatic gradient. It's possible they tapped into an overpressured reservoir -- but not by a factor of nearly 2 (or 20)
(3) The "pipe" you refer to would be the innermost production casing string that BP ran, the 7" x 9-7/8" string (7" at TD, swedged up at around 13000 ft). Details of the casing program are available, among other locations, at http://www.theoildrum.com/node/6462. ID for the string is dependent on the weight of the casing they ran (which I don't know), but it certainly isn't 18".
(4) We also don't know whether the flow is internal to the casing string or up the annulus. There have been suggestions from the circumstances of the blowout that the latter may be the case. Clearly, the flowpath chosen would affect the results of your flow calculations.
(5) Lastly, we know nothing about flow restrictions at the exit from the wellbore which may be "choking" the flow. I doubt that the pipe is simply cut cleanly off immediately above the BOP stack; although that may be the case today, it certainly wasn't for most of the blowout. The wellbore diagrams show riser from the wellhead to 1500 ft above it and then a sharp bend and a return to the seabed. Was that factored into your calculations as well?
I'm interested in your methodology and assumptions; would you care to elaborate?
(BTW, I'm a working professional chemical/petroleum engineer specializing in fluid flow and hydrodynamics in wellbores.)
Cheers,
Rudi
licet differant, aequabitur
Full Throttle.
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