Fixing the Gulf oil spill problem

[RonL]

Did you not get my PM?

And what's this about air bubbles?

I don't think a surface containment device the size of which you are talking about is necessary. The opinion on leak rate ranges from 500,000 to 4.2 million gallons of oil per day.http://www.pbs.org/newshour/rundown/horizon-oil-spill.html" , a containment area 100 feet across and maybe 20 feet deep would be all that is needed. IMHO of course.

ps. The non-water permeable ripstop material I mentioned is only http://www.seattlefabrics.com/nylons.html#1.9 oz unctd RS". So a 60" wide pair of the materials, sewn into a tube, at 1 mile length, would only cost ~$25,000. Must less costly than the nearly $1 billion dollars that spent so far.

And it comes in Royal, so I'm sure the queen would approve.

Just opened your PM,

Air bubbles, In post #27 I mentioned seeing a PBS.org document showing whales diving down and swimming in circles while they blew out large amounts of air, as the air moved upward it formed a circular wall of air bubbles that enclosed large schools of fish. Two or three whales provided the air, while others would swim up the center of the ring of bubbles and litterly devour large schools of fish.
One of the most amazing things I have watched.

Ron

 

[RonL]

Om,
If a tube of ripstop material is considered, I would think a bottom pressure of close to 2,500 psi would expand to such degree that near the surface, a velocity and frictional drag would be tremendous. Making a bottom opening of 15 or 20 feet in diameter, I think a surface opening might need to be near 100' or more. But then my smarts are not very great.

Kids are here, got to go.

Ron

 

[mheslep]

They would have to remove the LMRP. Once removed there will be a mandrel exposed that they can land another device with a collet type connector on and latch up to it. In other words they could basically land another new LMRP on it with the riser attached and cap the well.

The new device would be open to allow the flow to go up the riser until latched.

CS

Ok, that appears logical to me. I haven't heard much play on capping, so perhaps there are some other issues. For instance, maybe BP et al no longer thinks the BOP can handle a full 5000 PSI (or whatever it is) after the explosion, plus some hammer over pressure in the process of placing the cap. So instead, I speculate, that they prefer a continuing flow solution.

 

[OmCheeto]

Om,
If a tube of ripstop material is considered, I would think a bottom pressure of close to 2,500 psi would expand to such degree that near the surface, a velocity and frictional drag would be tremendous. Making a bottom opening of 15 or 20 feet in diameter, I think a surface opening might need to be near 100' or more. But then my smarts are not very great.

Kids are here, got to go.

Ron

I'm not very concerned about the well pressure. Once the oil escapes the steel pipe, it's at sea pressure. I don't know what the compressibility of crude oil is, so I don't know how much it will expand, but I would imagine it would be very small. Gas evolution might be a problem though. I think that's what started this whole mess.

hmm... a 120" circumference pipe would contain the flow at...

2*pi*r = c
r = 120/(2*pi) = 19.1 inches
a=pi*r^2=1146in^2=7.96ft^2
7.48gal/ft^3
49 gallons/second of flow yields:​

0.823 feet per second.

The head is at around 1 mile depth, so the oil would reach the end of the fabric pipe in...

(5280 feet)/(0.823 ft/sec)=6416 seconds
3600seconds/hour
6416/3600=...​

about 1 hour and 47 minutes.

 

[WmCElliott]

I'm gratified that their next funnel will be heated, I suppose electric heaters solve the insulation of the warm surface water for a mile through cold water.

BP does have a website dedicated to ideas for fixing the problem, and it seems to connect you to Red Adair's company directly.

 

[Geigerclick]

They will also be using Methanol in the new cap.

 

[russ_watters]

I'm a little surprised there doesn't exist any kind of valve that can be attached somewhere along the pipe, then having a slit cut in the pipe, then sliding a blast-gate type valve in place to stop the flow.

...or...since this is a 9" pipe inside a 21" pipe, why can't you just drill a 9" hole through the two pipes and insert a 9" diameter rod/pipe into the hole?

 

[pgardn]

And this is all having to be done by robot submersibles... Controlled by people that might be rockin and rolling on the surface. Pretty amazing. Amazingly difficult. I wonder how many of these things have run into each other or have gone out of commision. BP is not giving a lot up.

Its possible that we might not want to drill wells 1 mile deep anymore if we cannot fix them. On the other hand, this is a huge experiment that will get some answers. Just wish it all had never happened. Its like having a well on Mars.

This is an interesting simple view of all that has been tried so far...
http://www.nytimes.com/interactive/2010/05/25/us/20100525-topkill-diagram.html?ref=us

This says nothing about using heaters, just warmer seawater and methane (did they mean methanol, I thought methane was hydrating forming the crystals? more methane solves the problem?)

 

[Geigerclick]

And this is all having to be done by robot submersibles... Controlled by people that might be rockin and rolling on the surface. Pretty amazing. Amazingly difficult. I wonder how many of these things have run into each other or have gone out of commision. BP is not giving a lot up.

Its possible that we might not want to drill wells 1 mile deep anymore if we cannot fix them. On the other hand, this is a huge experiment that will get some answers. Just wish it all had never happened. Its like having a well on Mars.

This is an interesting simple view of all that has been tried so far...
http://www.nytimes.com/interactive/2010/05/25/us/20100525-topkill-diagram.html?ref=us

This says nothing about using heaters, just warmer seawater and methane (did they mean methanol, I thought methane was hydrating forming the crystals? more methane solves the problem?)

I would tend to agree, or we require that a relief well be drilled at the same time as the primary well at these depths.

 

[mheslep]

I'm a little surprised there doesn't exist any kind of valve that can be attached somewhere along the pipe, then having a slit cut in the pipe, then sliding a blast-gate type valve in place to stop the flow.

I believe it's because it is not practical to put enough structural strength into the riser pipe to support the loads required of any kind stop valve. The total force on any given 19" (ID) pipe cross section might be ~500 tons. I would think only the massive BOP manifold on the sea floor could handle that kind of load.

 

[Geigerclick]

I believe it's because it is not practical to put enough structural strength into the riser pipe to support the loads required of any kind stop valve. The total force on any given 19" (ID) pipe cross section might be ~500 tons. I would think only the massive BOP manifold on the sea floor could handle that kind of load.

That would seem to be a huge strain, and even if this were foreseen that would not be plan A or B, as we see. Frankly, a version of the Top Hat that has time to be engineered and build with simulations, with a heat exchanger and veins for methanol seems as though it could work.

Apparently there are gulf wells at 10,000 feet, and the need for a less "surgical" approach than this LMRP would seem wise. The aforementioned Top Hat, along with the fabric mention earlier would seem to be the best approach.

That, or drill a relief well along with the primary in the first place!

 

[stewartcs]

I'm a little surprised there doesn't exist any kind of valve that can be attached somewhere along the pipe, then having a slit cut in the pipe, then sliding a blast-gate type valve in place to stop the flow.

...or...since this is a 9" pipe inside a 21" pipe, why can't you just drill a 9" hole through the two pipes and insert a 9" diameter rod/pipe into the hole?

Russ,

The riser isn't designed to contain pressure. Its primary function is to provide a conduit for drilling fluids.

The max mud weight typically used in deep water isn't more than about 16 ppg so the differential across the riser at 5000-ft is about 1934-psi. So the riser isn't design to withstand typically around 2000-3000 psi normally and that's just for collapse resistance in case it is voided for some reason.

The thicker the riser is, the more it weighs, and the more tension is required at the surface to keep it stable.

CS

 

[stewartcs]

I believe it's because it is not practical to put enough structural strength into the riser pipe to support the loads required of any kind stop valve. The total force on any given 19" (ID) pipe cross section might be ~500 tons. I would think only the massive BOP manifold on the sea floor could handle that kind of load.

They actually deploy the BOP/LMRP stack on the end of the riser and land it on the wellhead. The LMRP/BOP stack weighs typically around 800,000-lbf. That plus the weight of the riser can be over 1,000,000-lbf depending on the depth. An analysis I performed not that long ago showed a static load of 1,400,000-lbf for a 10,000-ft riser and over 2,400,000-lbf when the dynamics were added (for a particular environment).

CS

 

[mheslep]

They actually deploy the BOP/LMRP stack on the end of the riser and land it on the wellhead.

Interesting. I'd like to know more about the procedure - would be necessarily very slow on descent, with the load maintained while new sections of riser are attached one after the other. We see cable drops in the graphics of all the heavy gear in these Deepwater Horizon repair / salvage attempts.

The LMRP/BOP stack weighs typically around 800,000-lbf. That plus the weight of the riser can be over 1,000,000-lbf depending on the depth. An analysis I performed not that long ago showed a static load of 1,400,000-lbf for a 10,000-ft riser and over 2,400,000-lbf when the dynamics were added (for a particular environment).

CS

With no experience in this line, tensile strength that high (700-1200 tons) sounds plausible to me for a (very stable?) riser pipe, but not the shear and compression loads that would appear if a valve was somehow inserted into the pipe and operated at this reservoir pressure - that is what I was referring to above.

 

[stewartcs]

Interesting. I'd like to know more about the procedure - would be necessarily very slow on descent, with the load maintained while new sections of riser are attached one after the other. We see cable drops in the graphics of all the heavy gear in these Deepwater Horizon repair / salvage attempts.

They can typically run about three riser joints per hour. Each joint is either 75-ft (or 90-ft depending on riser design) in length. They are connected by a bolted flange typically. However there are other designs that can be used to increase the running rate.

Essentially they just connect new joints on top of each other until they reach the bottom. At that point they use a special joint called a landing joint to connect the stack to the wellhead. Then they unlock another special joint called a telescopic joint (TJ) to allow compensation of the vessel motions. The outer barrel of the TJ is connected to a tensioning system (either direct acting or wire-line type) to provide the necessary top tension to keep the riser stable.

There are of course more steps involved but that's the short version.

CS

 

[Geigerclick]

They can typically run about three riser joints per hour. Each joint is either 75-ft (or 90-ft depending on riser design) in length. They are connected by a bolted flange typically. However there are other designs that can be used to increase the running rate.

Essentially they just connect new joints on top of each other until they reach the bottom. At that point they use a special joint called a landing joint to connect the stack to the wellhead. Then they unlock another special joint called a telescopic joint (TJ) to allow compensation of the vessel motions. The outer barrel of the TJ is connected to a tensioning system (either direct acting or wire-line type) to provide the necessary top tension to keep the riser stable.

There are of course more steps involved but that's the short version.

CS

I say this seriously, I have found your posts extremely informative, and if you would be willing I wouldn't mind the long version for the sake of geek-satiation if nothing else!

 

[mheslep]

They can typically run about three riser joints per hour. Each joint is either 75-ft (or 90-ft depending on riser design) in length. They are connected by a bolted flange typically. However there are other designs that can be used to increase the running rate.

Essentially they just connect new joints on top of each other until they reach the bottom. S

Thanks! I was having difficulty in fathoming how the load (700-1200 tons) is transferred, hand-over-hand so to speak, from section to newly-added-section.

 

[Bernie100]

Leaking Oil Gusher in the Gulf

Does anyone know what the approximate temperature of the oil as it comes up the well is?

 

[Geigerclick]

Does anyone know what the approximate temperature of the oil as it comes up the well is?

A google search returned too many conflicting numbers and guesses. I don't know that such information has been made public. Remember, there is a significant fraction of the spew that is rapidly expanding natural gas, so I'm not sure that it is possible to ballpark based on prior measurements of oil at that depth.

 

[stewartcs]

Does anyone know what the approximate temperature of the oil as it comes up the well is?

It varies quite a bit. I'm not certain about this well. Normally there is a pressure and temperature sensor in the stack cavity that transmits the data to the surface.

CS

 

[stewartcs]

I say this seriously, I have found your posts extremely informative, and if you would be willing I wouldn't mind the long version for the sake of geek-satiation if nothing else!

The other steps are mundane really - like preparing the drill floor, the moon-pool area, skidding the stack to well center, hanging the string off in the riser spider, etc. Most of those terms don't mean much to the majority of the people who read this since they are industry terms given to specific equipment or to a process.

I've just given the big picture. But if you have specific questions I'd be happy to try and answer them.

CS

 

[stewartcs]

Thanks! I was having difficulty in fathoming how the load (700-1200 tons) is transferred, hand-over-hand so to speak, from section to newly-added-section.

Each joint is basically sitting in what we call a gimbaled riser spider. The spider sits over the well center on the drill floor while running or retrieving riser. The joint sits on a load shoulder in the spider and holds the entire riser string (with stack on the bottom of last joint) while the next joint is stabbed in and bolted up. The draw-works (big hoisting system) then picks up the string of riser so the spider can be opened partially and then lower down the full length of the joint that was just made up. The top of the new joint is the landed in the spider again (which is now closed around the joint again) and the process repeats.

It's called a spider since that's what a lot of the older ones looked like! The oilfield is notorious for naming equipment for common day things that they look like!

CS

 

[Geigerclick]

The other steps are mundane really - like preparing the drill floor, the moon-pool area, skidding the stack to well center, hanging the string off in the riser spider, etc. Most of those terms don't mean much to the majority of the people who read this since they are industry terms given to specific equipment or to a process.

I've just given the big picture. But if you have specific questions I'd be happy to try and answer them.

CS

They certainly have little meaning to me! Heh, thanks for hitting the high notes in this case, I feel sufficiently informed on this now.

 

[mheslep]

Each joint is basically sitting in what we call a gimbaled riser spider. The spider sits over the well center on the drill floor while running or retrieving riser. The joint sits on a load shoulder in the spider and holds the entire riser string (with stack on the bottom of last joint) while the next joint is stabbed in and bolted up. The draw-works (big hoisting system) then picks up the string of riser so the spider can be opened partially and then lower down the full length of the joint that was just made up. ...

Yes, I should have guessed there would be a hoist in the works somewhere. Thanks again.

 

[Geigerclick]

I have no experience with modern ROVs, but isn't this incredibly delicate work to be doing with remote feeds and ROVs? It sounds as though they could damage the riser relatively easily.

 

[Arizona]

What about series of detonations? This could be a quick fix until the relief well is drilled. Detonations can be performed in a matter of weeks. I hope they are not trying alternative methods for the sake of reusing the well bore or to continue to collect oil. They need to stop the oil ASAP.

Drill many small diameter holes lined with explosive ~1000 meters around the well bore. Use the series of detonations to implode the well hole and cover it with ruble (i.e. make the Pressure inside the well<Pressure outside the well). I almost feel that the extreme pressures of the environment would allow for more controlled explosions or implosion from the detonations. This could stop or slow the leak until the relief well is completed.

I did some rough calcs and oil pressure at ~5000 psi, one would have to implode and cover it with ~1000 meters of ruble. I wonder how many meters they can drill in a day?

I have not heard of ideas regarding detonations of the subsea architecture or an implosion of the well head. What are the risks besides letting the oil leak like it has been for the last month? I am sure the have the well bore mapped.

BP should release some stats on the problem (i.e. map/diagram of the well, P's, T's, and V's, effluent components, flow rates, surrounding material properties, etc.) so some independent engineers can be more serviceable

 

[pgardn]

Looks like the diamond cutter used to make a clean cut for the fitting got stuck...

I wonder if they try and somehow continue this cut?

August and the relief wells are looking like the goal now. Hopefully they got some other ideas, if the new fitting idea does indeed not work, to capture some of the oil. 2 1/2 months more of oil flow... that's not good.

God with the BP luck so far, the relief wells will probably miss the main well to plug the thing up.

 

[M Grandin]

I suggested this:

"POSSIBLE REMEDY TO BP OIL LEAK ? Is it not possible sinking succesively smaller (=less diameter) and smaller steel tubes inside present tube in the well? At the same time "gluing" them to surrounding tube. Resulting in a layered steel tube of smaller and smaller inner flow diameter? At last a solid steel shaft is inserted in the last most narrow cylinder. Never a very huge force would be needed to press these units into the remaining cylindrical hole. At least every new cylinder inserted into the wider outside, will decrease the flow - so at last hardly no oil is leaking through. Theoretically this must work. Perhaps also possible inserting a large number of steel bars successevely into the main tube according to the same principle. But the point using cylinders might be possibility minimizing dead space allowing oil leaking through. Just a layman suggestion, almost certainly already considered - but I guess all suggestions are interesting in this critical case. (This is a copy of what I wrote in an ATS thread - perhaps already suggested here) "

It could be added, that the longer tubes (that may be added in series) the larger tube surface area for "glue fixing" (or corresponding) them and the more weight to overcome pressure from oil/gas well - if sufficiently long concentric tubes they may overcome pressure by their own weight. The resulting layered steel tube of about 0.5 m diameter will weigh
about a ton per meter - and some 100 meters of this may overcome well pressure by
its own weight. Of course a heavy load above this afterwards
further secures the assembly.

 

[stewartcs]

I suggested this:

"POSSIBLE REMEDY TO BP OIL LEAK ? Is it not possible sinking succesively smaller (=less diameter) and smaller steel tubes inside present tube in the well? At the same time "gluing" them to surrounding tube. Resulting in a layered steel tube of smaller and smaller inner flow diameter? At last a solid steel shaft is inserted in the last most narrow cylinder. Never a very huge force would be needed to press these units into the remaining cylindrical hole. At least every new cylinder inserted into the wider outside, will decrease the flow - so at last hardly no oil is leaking through. Theoretically this must work. Perhaps also possible inserting a large number of steel bars successevely into the main tube according to the same principle. But the point using cylinders might be possibility minimizing dead space allowing oil leaking through. Just a layman suggestion, almost certainly already considered - but I guess all suggestions are interesting in this critical case. (This is a copy of what I wrote in an ATS thread - perhaps already suggested here) "

No.

1) they can't glue steel tubes together especially while the well is flowing.
2) even if they could seal the tubes together the pressure acting on the surface area on the bottom of the tubes would blow them out.

CS

 

[stewartcs]

What about series of detonations? This could be a quick fix until the relief well is drilled. Detonations can be performed in a matter of weeks. I hope they are not trying alternative methods for the sake of reusing the well bore or to continue to collect oil. They need to stop the oil ASAP.

Drill many small diameter holes lined with explosive ~1000 meters around the well bore. Use the series of detonations to implode the well hole and cover it with ruble (i.e. make the Pressure inside the well<Pressure outside the well). I almost feel that the extreme pressures of the environment would allow for more controlled explosions or implosion from the detonations. This could stop or slow the leak until the relief well is completed.

I did some rough calcs and oil pressure at ~5000 psi, one would have to implode and cover it with ~1000 meters of ruble. I wonder how many meters they can drill in a day?

I have not heard of ideas regarding detonations of the subsea architecture or an implosion of the well head. What are the risks besides letting the oil leak like it has been for the last month? I am sure the have the well bore mapped.

BP should release some stats on the problem (i.e. map/diagram of the well, P's, T's, and V's, effluent components, flow rates, surrounding material properties, etc.) so some independent engineers can be more serviceable

They are not trying to salvage this well. It is cheaper to cap this one and drill another new one than it is to try and save this one. It doesn't even make economic sense let alone common sense to try and save this well.

The rate of penetration (i.e. how much the can drill in a day) depends on many factors specific to the geology of the well and the equipment used.

In order to 'blow the well up' they would have to drill (like they are now with the relief wells) to insert the explosive device. Since that is risky (i.e. blowing up the well) and requires the same amount of time it's better to just kill it with the relief well.

CS