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What we know....and what we don't know related to the BP disaster....

May be sorry later, but here goes........

 

The title says "What WE know", but it should say "What I think we know...."

 

What "We" know..........

 

1.  It was technologically a tough well. If you have to set three full strings of casing and four drilling liners in a space of 13.000' (approximately), this is a tough well from an engineering and feasibility standpoint.

 

2.  They shut the well in before it blew out...about two or three minutes before.  I evidence the rapid gain in stand pipe pressure in the last two or three minutes.  Nobody can explain that without telling me the well was shut in.  They boys did what the well told them to do.

 

3.  Displacing with sea water before setting the final cement plug was NOT a factor.  They could have set it in mud, then pulled up above the plug and displaced with sea water.  No biggie.  Either way, in order to remove the riser, they had to displace the well before or after setting that final plug, or just pull the riser and let @ 2,350 bbls of synthetic oil based mud loose into the gulf.

 

4. Bottom hole pressure was @ 13.000 psi as evidenced by their TD mud weight of 14.0ppg and TD at @ 18,300 ft.

 

5. The tapered string of 7" on bottom and swaged up to 9 5/8" or 9 7/8" (whichever), was cemented in place with 51 bbls of cement.  By my calculations, that was an excess over guage hole of 20 bbls.  I have read recently that no caliper log was taken of the well as they depended on MWD and did not run an open-hole wireline log.  That is anecdotal evidence read on the web, and not substantiated.  So I don't really know if the hole was washed out 20 bbls over caliper.  Gotta figger formation at that depth won't wash out that bad, but they did have three 15" triplex pumps on board.  This is a "gray area" to me until I get more info.

 

Here's what I DON"T know.....

 

1.  Did anyone note a discrepancy between the amount of sea water being pumped down the drill pipe and the associated returns?  Unless you had a dedicated and monitored "second" surface system on the rig to do just that, then the answer would be that they could not track it barrel-for-barrel.  But did someone see "something wrong" in the displacement?  Nothing about the surface monitors submitted by Halliburton can track that, because it doesn't track what is being pumped to the work boat.

 

2. THE SINGLE MOST IMPORTANT UNANSWERED QUESTION.......When they set that final string of casing (after cementing) and lowered it into the seal assembly and released the 5,000' of drill pipe from the setting tool in the hanger......Did they have a way of monitoring the annular pressure outside that last string of casing?  I don't know and haven't seen a diagram or picture of their wellhead configuration, but I cannot conceive of a configuration where after setting the casing, they couldn't monitor the backside pressure.

 

Your thoughts and comments are certainly appreciated.

 

Deeper

 

 

 

 

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You can not monitor annulus pressure on a sub-sea well head behind casing.
The following was posted on 'Newsvine' last night in trying to provide some answers for another poster. I thought it was worthy of Drilling Ahead so here it is. It contains opinions and facts (hopefully). Corrections and differing opinions are welcome. The whole Deepwater Horizon incident has been a learning process for me.

"BP should not have to release more oil into the deep sea. BOP-area well pressure could be reduced by taking off flows like before to the Q4000 and Helix Producer - through the BOP top kill and choke connections. They could also now make a sealed connection to the top of the new three-ram stack to the Discover Enterprise. (Note: Different ships could be used if collection re-started.)

Very good reasons exist for not resuming collection. For one, this crude has a very high natural gas content (40%) and it can only be flared (burned) - an awful lot of carbon dioxide going to the atmosphere. Offshore mobile processing equipment for separating the well discharge to oil and crude is not available. The natural gas would have to go to LNG (liquified natural gas) tankers theoretically.

Flow from the well was successfully stopped - the equipment all held. The chances of something failing now are very low. And the intense monitoring would catch potential problems early.

BP's Kent Wells said this morning that 'the administration' had the final say in ending this pressure test (putting more oil into the Gulf?). Now that is just scary as hell to me! Our government has only shown incompetence at this end of the spill.

So the reservoir pressure at 18,200 feet is around 11,000 psi - a little lower than estimated. You have to add about 4300 psi (gravity force from reservoir to sea bed) to the measured 6745. All is OK with the temporary 'kill' of this well!"
Nice post- however as a note we do not have a LNG export plant here in the lower 48 states. We have several facilities to accept and convert LNG back to Natural Gas but no way to turn Natural Gas into liquid form to load on tankers. A LNG facility like this would cost a couple billion dollars. I have been a proponent of an LNG facility for several years. If we could export our natural gas it would become a global commodity and put a floor under pricing and give us all the much needed opportunity to tell this President to shove his renewable energy where the sun don't shine. Over and over the industry has asked him to support natural gas as our transportation fuel and he refuses. Its clean, its abundant and its right under our feet in quantities to last over 100 years. Someday we will have an export facility, and we will export our natural gas abroad and the prices here at home will go sky high all because this President did not support it as a fuel here first.

Also-for all we know the reason the pressure stopped building is because it is leaking off somewhere deep in the well into another formation. Everyone is putting the most positive spin on this possible and I truly hope they are correct but the fact remains that the shut in well did not reach the pressure they wanted it to and they are all still very quietly hoping that the gas is not escaping the well from somewhere else

Sorry-I am getting off topic-just wanted to let you know there is no way to convert this methane to LNG and load on tankers here
Curtis - Thank you for the information! I had no idea we had no LNG facilities in this country. This may be showing ignorance on this, but my impression was that we had high-pressure liquid NG pipelines. And the compression facilities to liquify the gas. I know storage and transport are at or near atmospheric pressure with the corresponding low temperatures.

Limiting this comment pretty much to on-shore oil, my understanding is that we flare tremendous quantities of natural gas. A small-scale example: In talking to a guy from Stanley, North Dakota recently, he said many new wells were being drilled in northwestern ND and that Stanley had more than doubled population in two years.

The crude there is low in gas content but it's enough that he said burning flares were a prominent part of their skyline - especially at night. My point: A lot of this valuable natural resource is wasted nation-wide with an awful lot of carbon dioxide being emitted. Still, your comments on it being clean and abundant fuel are certainly true.

Your take on the Macondo well pressure situation disagrees with mine - you may be right. I had said that disagreement was accepted and this is a personal learning process for a non-industry person.

Tony raised a question to a second previous post of mine that I'm going to try to answer out-of-place here. Yes, I had the other posts to that discussion (and had read them). I failed to state clearly that "I" (me, whatever) had simply chosen not to comment to the 'be kinder to BP' discussion earlier. And I may not be clear with this response either. Sorry!
Mike, I am telling my age perhaps, but I can remember when even refineries such as the Baytown Tx Humble Oil Refinery (now Exxon) flared nat gas as a waste product. We didn't need streetlamps much in Baytown when I was a kid--or anywhere else on the Hou Ship Channel--the sky stayed lit up every night from scores of flare stacks.
Hi Don York - I have been inside several refineries in mainly the northern, central U.S. for different reasons. Relatively small and multiple flares have been commonplace. The ones in Baytown and elsewhere along the coast must have been impressive.

The methane content of the Gulf reservoirs has been a real surprise to me. I followed the ratio of standard cubic feet (SCF) of gas to barrel of collected oil for the Discoverer Enterprise part of the time. My approximate figures showed this ratio going from about 2100 SCF/ barrel to some above 2300 later - an increasing gas content.

As a guess, the unrestrained rising Macondo 252 crude stayed all-liquid due to pressure for more than 1000 feet above the sea floor. Then it had to go into some wild expansion further up. BP's bottom-end dispersant use efficiency sure was not hurt by that.

So dispersant use is my one strong criticism of BP that I never wrote about. I did not feel that dispersant should have been used for the uncollected crude below the Gulf surface. All oil should have been allowed to surface with efficient surface mechanical collection following. The anticipated effect of bottom-end use: A considerably expanded Gulf 'dead zone' this year from the well-emulsified oil that never has surfaced.

I've rambled on here - Sorry!
Mike,
I have done the usual "google" research, and cannot find any backing for what I want to say.

I feel sure we have the ability to send LNG's out. LNG is a matter of supply of gas and horsepower to mash it.

We are number one in getting it done, if we can last until 2012.

You are spot-on in your post where you question our ability. We get rid of some drones, we can do anything..........

Herr Deeper........tehehehehehhe
Greetings, Deeper,

I did nothing more on our LNG capabilities after that earlier post. But more will be done in the next couple of days.

From previous reading and memory now, it seems like Shell in their huge Perdido Gulf operation is separating oil and gas at the sea bottom - 7,000 feet there (a guess). Methane would remain a liquid under the high pressure - maybe something like liquid-liquid centrifuging. Enuf - will study this further also.

Some of our comments here seem to fit the discussion well - "What We Know ---" - and then there is the 'don't know' part.
Here is a site of LNG Facts
Center for Liquified Natural Gas
http://www.lngfacts.org/About-LNG/FAQ.asp

The following is a quote from this site

"Upon reaching its destination, LNG is stored as a liquid before being warmed back into a gas and sent out via pipelines as natural gas. Even though there are only nine import terminals in the United States, there are more than 100 LNG production, transport and storage facilities across the country.

The United States also exports LNG to Japan from Kenai, Alaska. Without a pipeline or an LNG import terminal on the West Coast, it is impossible to bring the Alaskan natural gas to the lower 48 states for domestic consumption."


This export facility in Alaska is Americas only LNG Export facility- we have several import facilities, and we can even export the imports while they are still super cooled-but in the lower 48 states we do not have a facility to super cool mathane to -250 deg for export. The cost of the facilities run into the billions and take some deep pockets to construct.

Like I have always said- if you get one of these around the Gulf of Mexico- you will have Obama by the balls and Natural Gas will get the Presidential attention it deserves.
A LNG Export facility on the Gulf Coast would be a really great thing. There is a great deal of gas in close enough proximity to pipe in that we sure could keep it well supplied. Texas has the most Industrial friendly coast. Not very long ago they shut down Naval Station Ingleside. This would be a great location as it is right on the Corpus Christi Ship Chanel. I would love to see this happen it could really stabilize the natural gas drilling and production in the south. What do we or how can we try to make something like this start to happen.
Hi Kyle-
I think the best thing we could do to make this happen would be to vote Republican for the rest of our lives. I think Chesapeake was secretly in the process of trying to make something like this happen right before the bottom fell out of the markets.
Screw Aubrey McClendon and the mule he rode in on. He was one of Obama's biggest supporters along with GE, (one of the largest builders of windmills and gas turbines). They were made promises and invest hundreds of millions to get that idiot elected, and McClendon got screwed royally, and GE didn't get the best return they thought they were going to get. The Tax Payer has subsidized billions of dollars worth of windmills, another one of the biggest scams on earth, but GE was planing on a bunch or turbines getting the same treatment, but Barry turned his back on them once he got the job. McClendon had to sell a ton of his own stock and lease land to Statoil to keep Chesepeake liquid and the foreign banks from calling in their notes. They took it in the keyster with the AIG fallout, and I say good riddance. If you remember during the election, every time you saw a Barry Obama advertisement, it was followed up with a GE or Chesapeake ad, back to back, every time. They got in bed with the sumbitch and anything bad that comes to them, so be it. I sent out a letter to McClendon demanding to be dropped from their vendors list when I found out their political agenda, and pulled six longtime consultants off their rigs. Won't give them the time of day if their total existence depended on it.

And on subject, we would have no use for a LNG "export" facility on the Gulf Coast, because we don't have enough NG as it is. The only reason we export out of Kenai, is that they have no place else to send it, since California won't allow an import dock on their coast. So hey, let them continue to pay higher utility rates than anyone on earth.......

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