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BP disaster and liquid nitrogen 1

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ione

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Oct 22, 2009
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Would it possible in your opinion to reduce or stop the crude oil flow using LN to freeze it?
 
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The gas hydrates alone stopped it inside the dome and kept it from entering the pipe to the surface. The trick is getting the hydrates to form in the well bore, or a big and heavy enough dome that will make a seal and won't leak oil from under the skirt, should the hydrates plug the pipeline.

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"Being GREEN isn't easy" [frog] Kermit
 
I suspect getting enough heat transfer area at the wellhead to freeze the crude coming out at 5,000 barrels/day with liquid N2 would be physically impossible. Just not enough ft[sup]2[/sup] there.

Good luck,
Latexman
 
Ever tried to do an above ground freeze plug on a line which had a bit - just a bit - of flow in it? With the exception of sulfur lines, that's quite difficult.

I could see hydrates reducing the flow if they could be made to form, but stopping the flow would be quite challenging.

jt
 
There was quite a discussion of using LN2 on the MMS website.

The latest information says that the gas component of the flow has increased significantly. This would hinder any attempt to use LN2. The additional gas flow would in the opinion of some would enhance the chance of the "junk shot" working.
 
They have decided on using the smaller "top hat" type containment dome. It seems like they are hell bent on trying to inject methanol, which in an ideal situation would work. However, at this point, I don't blame BP for anything they try.



"Scientists dream about doing great things. Engineers do them." -James Michener
 
Maybe one option would be to "kinetically deform" the riser using detna-charges and an approporate enclosure, to be installed by a US Navy mini sub around a section of the riser. It should be possible to squish the pipe to an ID of less than 1" with a properly designed charge.
 
Looks like gas (NG) is running along the upper diameter and liquid (crude oil) along the bottom diameter and the ratio of the mass flow of each is changing significantly and quickly. Definately two phase flow.

Good luck,
Latexman
 
According to a poster well versed in the art and science of offshore drilling the riser pipe apparently cannot hold the shut-in well pressure which you would get almost immediately if you clamped the pipe. From what little information I've come across is that you have to kill the flow at or very near the BP.

According to some reports the well failed a very critical pressure test just prior to the "kick" and boom. According to my contacts with a couple of drillers that work off shore you don't have much choice when a well fails the "negative pressure test". I haven't had chance to get this test defined, but as I understand it the there are three points on the well head where the pressure should balance and if not you have a leak somewhere in the cement job. This well failed 2 test, one just prior to the blowout and explosion.


 
A negative pressure test is when the pressure inside the well is lowered to find out if any gas can or is leaking from the formation into the well. The first test was apparently bad and they retested. The 2nd test registered 1400 psig in the drill pipe with 0 psig in the kill and the choke lines, a sign that the formation was leaking gas into the drill pipe.

**********************
"Being GREEN isn't easy"
....[frog] Kermit
 
Adm. Thad Allen USCG was just on the all the news channels with a little new information. H would come off the 5000 bbl/day estimate. he key point was that the oil was not the giant monolithic spill it once was, it's just a bunch of smaller one scattered over a wider area.

BP is going to insert a tube (8" from another source) into to the open end pipe (API 21") to "siphon" some of the oil to the surface. They hope to be able to install something like a packer if they have any success.

They are to test the "top hat" today.

Not sure about this one as a reporter interrupted. They have either take radiographs at the BOP or going to. This is check the position of the valves.

They have determined (measured) that the pressures are lower than originally assumed.

They are looking at cutting the riser and putting a well control valve above the BOP.

They are also looking at replacing the BOP itself.

They still have the "junk shot" in the works.

At times I wondered who he speaking for the USCG or BP.

CNN also found a report from LNL where the Russians used nuclear explosions to kill four out five wild welds.

 
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