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oil leak gulf of mexico 5

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CH5OH

Petroleum
Oct 4, 2009
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just some open topic...
being an engineer, how would you go about to seal off a leaking well @ 1500m depth.
try to get Redair to get into a divesuit, convincing him the depth is kinda exagerated ?
Any bright idea's ?
 
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Big Inch- this is what is worrying me. For decades drilling engineers like me have put all our faith in the BOP as the ultimate well control solution. Where BOPs did fail we could understand it- on the Ekofisk blowout part of the BOP was upside down (!!) and on the Ocean Odyessey the BOP failed after very, very extended stripping operations.

In terms of subsea stacks we thought the dual redundancy of the yellow pod and the blue pod, coupled with emergency BOP control systems meant the BOP would always work (in fact the main concern recently has been a subsea BOP working when it wasn't supposed to- unplanned BOP and LMRP disconnects).

So why didn't the Deepwater Horizon's BOP function? (or not function fully)? Two annulars, four pipe rams (ie two pipe rams, probably variables, a blind/ shear ram and probably a blind ram) and none managed to shut the well in... That, for me is one of the biggest questions to be answered.
 
DrillerNic,
That question is bothering a lot of people other than your self.
Some of the things that are known.

According to testimony the annular seal had been compromised earlier when the DP had been inadvertently moved while the seal was energized. Chunks of rubber were detected on the mud screens earlier. This may have positioned a DP joint in the top shear ram which does have the force needed to shear the joint.

The BOP hydraulics were is in disrepair as there was at least one known leak on the primary hydraulic system. The question has been asked was they secondary hydraulic system fully pressurized?

There was no testing done prior to installation other than a partial pressure test with a dummy ram.

The question arises was there is a piece of casing along with the DP in the bottom shear ram path.

Why couldn't they apply hydraulic pressure on the BOP early on? They showed a hydraulic intensifier on the bottom for several days. Now I think they are concerned that they will shut in the well and over pressure the casing, a very bad problem if it is compromised in some way.

From what I can ascertain they are several schools of thought on exactly what is holding the drill pipe in the BOP.

Here is a question I've asked and as yet to receive an answer is how much they will be able to choke the flow if they have to cut loose for a storm. At the present they will have to open everything up on the BOP to keep the pressure down at the BOP. Hopefully they will get their new hardware installed prior to any storm which is supposed to have better handle storm conditions.
 
biginch, the reference to the lunar project was a repply to:all tricks are used up, which sounded a bit like I can't do it.but i guess you're right, while changing the level of comittment changes what you can and can't do, it does come down to a cost/risk benefit analyse.Since the quantity of of red snappers filing a law suit will be rather small, the environmental dammage/commitment to seal off the leak also will be a cost/benefit calculation.It looks like BP has been granted the exploitation rights only for the well and the f.ck up rights for the whole GOM.
 
Redfish don't vote either, except through the Gulf Coast Conservation Association members; a pretty small representation. Great fish though.

"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO BP
"Being GREEN isn't easy." Kermit[frog]
 
I am an Aerospace Engineer. I have an idea to regain control of the well in the Gulf but I am out of my element and can't say for sure if it is even feasible. Experts, please take a look at the idea (linked below) and tear it apart. I need honest feedback. Thank you.

 
After you achive docking, what will you do about the hydrates? It looks like a higher-tech version of the concrete tophat, which failed due to hydrate plugging.

"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO BP
"Being GREEN isn't easy." Kermit[frog]
 
Aside from the above post another major problem is being able support the apparatus on the bottom. The sea floor at the well site is a very thick layer silt sitting on a very thick layer of mud. When this well was started probably the first 300-500 feet of large casing was just pushed into the sea floor, there was not drilling.
Early on you probably heard of them putting mud mats on the bottom to support some equipment or tools and the only problem these mats don't support very much.

Bp is also extremely worried about disturbing the casing in any way after the top kill attempt due concerns about integrity of the casing.

I played around with the idea of using corrugated silo sections or drainage pipe to make s standpipe to the surface. My contraption would be allowed just sink into the mud to seek it's own level. Talked myself out of this due to the horrendous currents at times in this area and the little problem of gas separation.
 
the basic idea of nathanian isn't to bad but its a complex design.lots of things can go wrong...
the hydrates which formed with the tophad can be avoided by not using a tophad, which basically collected the hydrates in the much smaller top connection.to my humble opinion you need to:
1.provide anchorage onto the BOP:some big silo which slides over the BOP, to be filled with concrete
2.provide a diverging (as opposit to tophad)blow of line with shut of gate valves on top of BOP(total area in excess of area leaking pipe),valve wheels to be compatible with ROV hydraulic arm.
3.pour concrete in the silo,to anchor the blow of line to the BOP
4.close the valves one by one, slowly reducing the flow to 0
5.engage a fleet of barges with brush type conveyor belts to collect the oil at sea (easier to collect at sea than scrape it of the beaches)
6.have a beer and settle the dammage claims
 
Are there any components that compress too much under 2200 psi water pressure causing contact surfaces to be loose when arriving at 5000 ft depth? Are there any tubes that will collapse under 2200 psi external pressure. What's the construction schedule look like.

"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO BP
"Being GREEN isn't easy." Kermit[frog]
 
BigInch,

BP seems to have gotten a handle on venting and controlling the formation of hydrates, (see their latest cap), so I've left those transferable details to them.

While I was putting my solution together I knew there were a lot of things I didn't know so I limited myself to using only those technologies or skills that BP has already demonstrated. We know they can build and handle big structures, we know they can position large structures with precision, we know they can handle hydrates, and we know they can pump cement. Put it all together (with a few minor twists) and you've got a solution that BP should already know how to execute.

I'm considering most details (such as the type of rubber to use in the seal) to be design details, not design problems. If the general concept is deemed feasible then someone else (more qualified than me) at BP can add fidelity to the design.

I'm just looking for show-stoppers in the core concept: Use a modified open-top silo as cement form to join a new LMRP to the BOP stack.

Thank you (and unclesyd and CH5OH) for your input.

 
The latest number just out on CNN is "They are not saying it could have been leaking 60,000 BOPD every day." Finally hit my number!

"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO BP
"Being GREEN isn't easy." Kermit[frog]
 
i read in the newspaper today holliwood star costner sold 32 centrifugal separators to "the project"
lol, the problem isn't to separate the oil from the water it's the logistics of loading the oil at sea and unloading the oil onshore
the TOP KILL "project name" is suggesting the flow at a certain point is getting killed.Being more of a TOP RESURECTION, it explains the need for flaring/discharging on the surface....
 
Tthe reason for flaring the gas is that there is no other way to get rid of it. Many have suggested that that it be converted to LNG and the only problem with that is there isn't any available floating LNG facilities drifting around.
The noise and fumes form the existing flare are very big problems with workers on the rigs, fire suits, ear plugs, and respirators.
If the Evergreen Flare System makes anywhere near the noise that old incinerator ship that showed up in the Gulf several times it's going to be tough all around the well site.

Talked with some people last night and two of the big DW rigs have picked up and headed to Africa and Brazil. This person just came off the Enterprise last Thursday and has been called back for this Friday, said he felt like an Alaskan crab fisherman.

 
unclesyd, you are missing my point:
if the leak is sealed off, there is no need for a pipe to the surface, there is no need for tankers, there is no need for gas/oil separation, there is no need for a flare of any kind.There is no need to deal with hydrates.When the rig sunk, the connection between the well and the rig failed on the weakest link: the riser buckled in three places,first on the top,last above the BOP.If the BOP was designed to withheld the pressure of the well,then it is still capable of providing enough foundation for a new shut off valve to be mounted on top.The fear BP is expressing :the below structure might be damaged is more the fear of getting linked with taking a wrong dessision.wrong dessisions have been made which caused this disaster.Humans are granted intelligence, evolved from taking some good dessisions in the past:
running away from the big animals so you don't die and get eaten.killing small animals to eat so you don't die.Some died from taking the wrong dessision.All those who didn't make a desission died either way from not getting served dinner or getting served as a dinner.Time is defining the X factor in the simple equation:
dammage=X times Valdez
 
The big worry is the very high probability that there is a leak in a section of the casing that could cause all manner of grief in the formation if pressure is increased in the upper section of the well bore. If they fracture the formation there is very good possibility they could open the reservoir to the sea bed by the resulting fissure. This possibility is exacerbated by the apparent loss of a rupture disk in the casing. Also there is one section of casing string that has a burst pressure lower than the shut-in pressure that would develop if the BOP is closed off.

The BOP can handle the shut-in pressures OK but the casing cannot.

 
I did read somewhere that the selection of pipe was critized as probably not the best for the job at hand. One of those links up there.

"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO BP
"Being GREEN isn't easy." Kermit[frog]
 
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