News Is Offshore Oil Drilling Truly Safe?

[PRDan4th]

Or that could cause a second explosion.

How?

 

[IcedEcliptic]

How?

The oil heats the accumulated hydrates crystals which form in the pipe, causing either a rupture, or back pressure on the pipe. I am not saying that this would destroy the rig in place, but it would certainly damage the container, and that is not a risk that can be afforded.

 

[PRDan4th]

According to BP:

"Work Continues to Contain Spill and Mitigate Impact. The containment dome arrived on location yesterday, from Port Fourchon, Louisiana, ready to be deployed. Once lowered to the sea bed, the next steps will be to connect the 40x24x14 feet steel dome, which weighs almost 100 tons, to a vessel on the surface. Once this operation is complete it will be possible to assess the effectiveness of the solution."

(http://www.bp.com/bodycopyarticle.do?categoryId=1&contentId=7052055)

My calculations show a lift force about two-thirds of the 100 Ton mass of the box.
therefore the box should stay on the bottom. I used a specific gravity of .85 for the hot oil and hydrate mix.

 

[PRDan4th]

The oil heats the accumulated hydrates crystals which form in the pipe, causing either a rupture, or back pressure on the pipe. I am not saying that this would destroy the rig in place, but it would certainly damage the container, and that is not a risk that can be afforded.

The ice crystals will be melted before the pipe is attached to the funnel. After the oil has filled the box, hydrates will not form as the temp. is too high. Hydrates will not form in hot oil.

 

[IcedEcliptic]

The ice crystals will be melted before the pipe is attached to the funnel. After the oil has filled the box, hydrates will not form as the temp. is too high. Hydrates will not form in hot oil.

They already attempted to use this containment, and hydrates DID form, stopping work. Why create a pressure vessel of methane hydrate and oil? The hydrates release the methane, which would be subject to compression or back-pressure on the pipe.

 

[PRDan4th]

They already attempted to use this containment, and hydrates DID form, stopping work. Why create a pressure vessel of methane hydrate and oil? The hydrates release the methane, which would be subject to compression or back-pressure on the pipe.

Yes, the hydrates did form when the box first was set over the well. One must continue to fill the box with oil and gas mixture and evacuate the sea water out of the bottom creating a warm oil/gas mixture at a temp. higher than the disassociation (melting) temp. of the hydrate. Once the dome is full of warm oil the plug will melt and oil will flow. Then attach a pipe to the surface ship.

By the way, the box does not become a pressure vessel as water will be at the same pressure as bottom of sea

 

[Astronuc]

I think the problem was that the ice (clathrate?) formed so quickly that the box became buoyant such that it would not seat properly over the leak. So they set it to the side. It if iced up sufficiently, then perhaps the oil would not flow into it such that the ice would melt.

 

[PRDan4th]

I think the problem was that the ice (clathrate?) formed so quickly that the box became buoyant such that it would not seat properly over the leak. So they set it to the side. It if iced up sufficiently, then perhaps the oil would not flow into it such that the ice would melt.

I think you are right. The top hole plugged first and then some of the methane gas formed in the vessel creating a buoyancy of the box. The oil and clathrate alone would not be light enough to lift the 100 Ton vessel.

 

[PRDan4th]

This is a very difficult problem to solve. The neck of the funnel must be kept hot enough to melt the hydrates and keep them from reforming. the gas bubble formed in the box acts as an insulation keeping the warm oil from heating the hydrates in the top of the box.

Now what has to be done is heat the funnel top to a temp that melts to hydrate blockage (electric resistance heat?). then the riser pipe must be kept above the melting point all the way up to a point where hydrates form. This may require a hot water tracing in an annulus pipe all the way up to the ship. Still the evolved gas will be a great problem as it will expand over 140 times between the sea floor to the surface. Flaring of this gas may be required.

 

[Frame Dragger]

Would I be wrong in saying that the answer to the OP title is now a clear: "No". Whatever else may be true, this would seem to indicate that safety and recoverability are ongoing experiments at these depths.

By the by, it seems that they are going to try and seal the well-head now, for reasons which are still unclear. Their plan as stated has been to pump ethanol or hot water into the "box" to preheat the water and prevent hydrates from forming. I'm not sure why they seem to have moved into a "plug it an see" mode, but I wonder if this is likely to be effective? The depth makes all of this very risky in my view, and since I was last, um, able to post, the environmental impact has made itself far better known.

The effect of these dispersants (they are using two) is questionable given the saturation of the water column with oil, now dispersed oil and toxic dispersants. Toxic, I might add, to humans, as studies in Alaska have shown. The toxicity to fry and eggs or oyster/shrimp young is unclear in the words of one marine toxicologist. It seems wise to stop dumping surfactants into the damned gulf thus compounding this event.

http://www.nola.com/news/gulf-oil-spill/index.ssf/2010/05/chemicals_used_to_fight_gulf_o.html

I realize this is not merely cosmetic, but the notion that this will really help an ongoing leak of this size to "Degrade" seems specious.

 

[PRDan4th]

Would I be wrong in saying that the answer to the OP title is now a clear: "No". Whatever else may be true, this would seem to indicate that safety and recoverability are ongoing experiments at these depths.

By the by, it seems that they are going to try and seal the well-head now, for reasons which are still unclear. Their plan as stated has been to pump ethanol or hot water into the "box" to preheat the water and prevent hydrates from forming. I'm not sure why they seem to have moved into a "plug it an see" mode, but I wonder if this is likely to be effective? The depth makes all of this very risky in my view, and since I was last, um, able to post, the environmental impact has made itself far better known.

The effect of these dispersants (they are using two) is questionable given the saturation of the water column with oil, now dispersed oil and toxic dispersants. Toxic, I might add, to humans, as studies in Alaska have shown. The toxicity to fry and eggs or oyster/shrimp young is unclear in the words of one marine toxicologist. It seems wise to stop dumping surfactants into the damned gulf thus compounding this event.

http://www.nola.com/news/gulf-oil-spill/index.ssf/2010/05/chemicals_used_to_fight_gulf_o.html

I realize this is not merely cosmetic, but the notion that this will really help an ongoing leak of this size to "Degrade" seems specious.

No, you are not wrong in stating that deep water oil production is not "safe". Deep water oil exploration and production in known Hydrate areas is not only not safe, it dangerous! Ships can be sunk or capsized in large gas blow-outs. This is too bad because deep water was expected to be very large in new oil production. This episode could could be to offshore oil production as TMI was to nuclear power.

 

[aquitaine]

Obama has sent SWAT teams to inspect the oil rigs, see for yourselves.I have a question, since when did SWAT have investigative power?

 

[Cyrus]

Obama has sent SWAT teams to inspect the oil rigs, see for yourselves.


I have a question, since when did SWAT have investigative power?

Don't you mean, SWOT teams? (There is also a "http://www.swat-ab.ca/index.php?option=com_content&view=category&layout=blog&id=61&Itemid=86"" team that deals with oil spills in Canada, so he might have meant that as well).

 

[Sbrownstein]

Something here doesn't compute. Like most of us, I have only a couple of days experience in researching methane hydrates, however it would appear that they are generated by the combination of relatively high pressures, methane gas and pre-crystalline water. With that in mind, we must assume that hydrates are not present in the oil flow from the deposit at 18,000 feet, but that methane gas is present and mixed with the oil. If we wanted to form as much hydrate as we possibly could, we would bubble the methane into the cold seawater and position a surface directly above the gas stream to trap the small hydrate crystals that were forming. In other words, lower a great big containment box over the gas/oil stream and let the oil continue to rise and collect the hydrates on the inner top surface of the box...until the outlet hole in the box plugged completely with methane hydrate.

Now, however, if we fill the box with something other than water (lighter of course) and close the outlet and position it over the leak, the box will rapidly fill with oil that displaces the water or other compound. The oil would then begin to leak out of the bottom of the box, where it interfaces with the mudline! HOWEVER, at this point hydrate formation would stop since the methane in the flow would no longer come in contact with sea water, which is required for hydrate formation. If we then tap the box (open the valve) and always maintain oil over the end of the riser, hydrates would stop forming and we could allow the oil to be placed in a tanker and removed from the environment.

By my calculations, if the leak is something like 5000 barrels a day, the available volume in the box (looks like say 15' high by 12 by 12) would contain about 2 hours of oil without allowing any oil up the vent pipe.

If the hydrate was already present in the oil from the production casing, why hasn't it begun to plug the crimps in the line itself? Most of the literature indicates that hydrates are concentrated in the sediment layers and have been formed as methane has bubbled up, combined with cold seawater and become trapped by the sediment.

As a result, it would seem that the absolute worse thing we could do would be to lower the box over the leak with an open vent for the oil to continue to escape.

What am I missing?

 

[IcedEcliptic]

Something here doesn't compute. Like most of us, I have only a couple of days experience in researching methane hydrates, however it would appear that they are generated by the combination of relatively high pressures, methane gas and pre-crystalline water. With that in mind, we must assume that hydrates are not present in the oil flow from the deposit at 18,000 feet, but that methane gas is present and mixed with the oil. If we wanted to form as much hydrate as we possibly could, we would bubble the methane into the cold seawater and position a surface directly above the gas stream to trap the small hydrate crystals that were forming. In other words, lower a great big containment box over the gas/oil stream and let the oil continue to rise and collect the hydrates on the inner top surface of the box...until the outlet hole in the box plugged completely with methane hydrate.

Now, however, if we fill the box with something other than water (lighter of course) and close the outlet and position it over the leak, the box will rapidly fill with oil that displaces the water or other compound. The oil would then begin to leak out of the bottom of the box, where it interfaces with the mudline! HOWEVER, at this point hydrate formation would stop since the methane in the flow would no longer come in contact with sea water, which is required for hydrate formation. If we then tap the box (open the valve) and always maintain oil over the end of the riser, hydrates would stop forming and we could allow the oil to be placed in a tanker and removed from the environment.

By my calculations, if the leak is something like 5000 barrels a day, the available volume in the box (looks like say 15' high by 12 by 12) would contain about 2 hours of oil without allowing any oil up the vent pipe.

If the hydrate was already present in the oil from the production casing, why hasn't it begun to plug the crimps in the line itself? Most of the literature indicates that hydrates are concentrated in the sediment layers and have been formed as methane has bubbled up, combined with cold seawater and become trapped by the sediment.

As a result, it would seem that the absolute worse thing we could do would be to lower the box over the leak with an open vent for the oil to continue to escape.

What am I missing?

BP and government do not want to risk sealing an incredibly valuble well? From what I have heard, this box can be filled with junk and sealants to form a cap, but trying this first makes sense. Sealing the well is what causes the problem in the beginning, yes? What do you seal it with now, without risking another rig?

 

[IcedEcliptic]

I will now answer my own question: http://www.cnn.com/2010/US/05/09/gulf.oil/index.html?hpt=T2&hpt=C1

Huh.

 

[Sbrownstein]

No, I think that you are confusing two separate strategies. Right now the pressure at the end of the riser is "slightly above" the water pressure at the 5000 depth. I say slightly above since 200,000 gallons or so a day are managing to leak out and eventually reach the surface. This pressure is controlled by the "kinks" and crimps in the old riser both at the preventer and between the well and the open end of the riser. If they try to plug the free end of the line (somehow) the pressure on the plug will then rise to meet the actual wellhead pressure, which we don't know, but is generally estimated to be much, much higher. Who knows it the plug or the damaged riser will hold as the pressure increases. This is no different than home plumbing or current flow and voltage in an electrical circuit that has finite resistance. A permanent "junk shot" would require unrestricted access to the wellhead, or at least to the either partially or completely non functional blow out preventer. To do this they will have to remove either the riser or the BOP itself, attach a new riser to it and pump all kinds of stuff like concrete, old tires, mud, etc down into the well itself. This is clearly opening pandora's box since once the restrictions are removed, the well will release oil in a pretty much uncontrolled state and could make the situation far far worse if they were unsuccessful in securing a plug.

As far as the "value of the well" is concerned, they are currently drilling not one but TWO "rescue wells," presumably at about $100M each and spending maybe $10M a day on cleanup efforts. I am sure that they would love to destroy the current well and stop the bleed...if they could only figure out how to do it.

 

[aquitaine]

Don't you mean, SWOT teams? (There is also a "http://www.swat-ab.ca/index.php?option=com_content&view=category&layout=blog&id=61&Itemid=86"" team that deals with oil spills in Canada, so he might have meant that as well).

SWAT in america means "Special Weapons And Tactics" (or their original name Special Weapons Attack Teams), a part of local police forces for dealing with heavily armed criminals, hostage situations, that sort of thing.


And I'm pretty sure I heard the "A" when he said SWAT.

 

[PRDan4th]

Something here doesn't compute. Like most of us, I have only a couple of days experience in researching methane hydrates, however it would appear that they are generated by the combination of relatively high pressures, methane gas and pre-crystalline water. With that in mind, we must assume that hydrates are not present in the oil flow from the deposit at 18,000 feet, but that methane gas is present and mixed with the oil. If we wanted to form as much hydrate as we possibly could, we would bubble the methane into the cold seawater and position a surface directly above the gas stream to trap the small hydrate crystals that were forming. In other words, lower a great big containment box over the gas/oil stream and let the oil continue to rise and collect the hydrates on the inner top surface of the box...until the outlet hole in the box plugged completely with methane hydrate.

Now, however, if we fill the box with something other than water (lighter of course) and close the outlet and position it over the leak, the box will rapidly fill with oil that displaces the water or other compound. The oil would then begin to leak out of the bottom of the box, where it interfaces with the mudline! HOWEVER, at this point hydrate formation would stop since the methane in the flow would no longer come in contact with sea water, which is required for hydrate formation. If we then tap the box (open the valve) and always maintain oil over the end of the riser, hydrates would stop forming and we could allow the oil to be placed in a tanker and removed from the environment.

By my calculations, if the leak is something like 5000 barrels a day, the available volume in the box (looks like say 15' high by 12 by 12) would contain about 2 hours of oil without allowing any oil up the vent pipe.

If the hydrate was already present in the oil from the production casing, why hasn't it begun to plug the crimps in the line itself? Most of the literature indicates that hydrates are concentrated in the sediment layers and have been formed as methane has bubbled up, combined with cold seawater and become trapped by the sediment.

As a result, it would seem that the absolute worse thing we could do would be to lower the box over the leak with an open vent for the oil to continue to escape.

What am I missing?

The oil being produced from the deep well is too hot for hydrates to form. All three components are in the oil stream; oil, gas and water. The reason that hydrates form at the sea bed in the box is that the temperature is cold. the large amount of sea water in the box cools the oil/gas stream and reacts with the gas phase to form hydrates. If this stream can be kept hot all the way up the pipe the the surface hydrates would not form.

 

[Frame Dragger]

SWAT in america means "Special Weapons And Tactics" (or their original name Special Weapons Attack Teams), a part of local police forces for dealing with heavily armed criminals, hostage situations, that sort of thing.


And I'm pretty sure I heard the "A" when he said SWAT.

Surface Water Assessment Team (of the Minerals Management Service, part of U.S. Dept. of Interior) http://www.answers.com/topic/swat-2

http://en.wikipedia.org/wiki/Swat

There are also SWOT teams.

The only people frothing about this being a Special Weapons and Tactics team are right-wing lunatics. Seriously, check on google, it's about 3 or 4 pages of "policestate" and "abovetopsecret" crap.

EDIT: The funny bit here, is that as you said, SWAT is LOCAL to police forces. There is a federal equivalent, and it's the FBI's HRT (Hostage Rescue Team), so if the feds were to do such a thing, they wouldn't haul some random county's SWAT offshore. Critical thinking people, come on.

 

[Gokul43201]

SWAT in america means "Special Weapons And Tactics" (or their original name Special Weapons Attack Teams), a part of local police forces for dealing with heavily armed criminals, hostage situations, that sort of thing.And I'm pretty sure I heard the "A" when he said SWAT.

You're just guessing, really ... and likely guessing wrong.

5. Don’t you think it’s crazy how SWAT teams are going out to examine rigs in the Gulf? There are definitely some folks who do. Former Reagan cabinet adviser Mark Levin has called it a “stunner,” and says, “I think those SWAT teams are there in coordination with the attorney general’s office, the Interior Department, Homeland Security, maybe the EPA to gather records, to seize records at these sites and to lay the foundation for more government takeovers.” But are they SWAT teams? Or teams from SWAT Consulting? Or Soil and Water Assessment Tools? Or strengths, weaknesses, opportunities, and threats (SWOT) teams? Or does it simply stand for Swift Action Team? The latter seems the best guess, but feel free to let your conspiracy theories run rampant until we get a definitive answer.

Link: http://www.pbs.org/wnet/need-to-know/five-things/the-oil-spillleakfiasco-in-the-gulf-of-mexico/363/

See also:
http://voices.washingtonpost.com/federal-eye/2010/04/oil_spill_the_governments_resp.html

INTERIOR DEPARTMENT:
The department deployed SWAT teams from the Minerals Management Service to inspect 30 drilling rigs operating in the deepwater sections of the Gulf of Mexico. Inspections should be completed within the next week, according to an Interior Department spokeswoman.

Inspectors will check to see whether the rigs have conducted blow-out preventer tests and inspect related records, the spokeswoman said. The teams will also verify that emergency well control exercises are taking place. Inspectors will then inspect 47 deep-water production platforms in the gulf, a process that will take longer than rig inspections because of the complexities of the structures.

I dug into the Minerals Management Service website for any mention of SWAT (or SWOT) and found the following in a 2008-2012 Production Business Plan:

• Workload Inventory Reduction/Consolidation of Production Accounting and
Verification Processes:

o Consolidating all production accounting and verification processes
including OGOR reporting and error correction, PASR reporting and error
correction, and LVS and GVS exception resolution.
o Identifying efficiencies that can be gained from consolidated processes.
o Obtaining permanent and temporary additional staff for SWAT efforts. [/color]
o Prioritizing system changes required to improve processes.​

​

Link: www.mrm.mms.gov/StudyRepts/PDFDocs/PROD5YrBP.pdf[/URL]

I think it's safe to say that Tactical Weapons teams are not currently crawling all over the rig.

 

[Borg]

I think that the SWAT acronym has been hijacked over the years to include any situation where a specialized team needs to go in and deal with an unusual problem. Could this be part of the confusion here?

 

[Frame Dragger]

When has reality ever burdened such great minds as Rush Limbaugh and others who make him look the voice of sweet reason?

It appears that Mark "I hear voices" Levin started this idiocy, and as usual the right-wing punditry ran with it. Doubtless there will be retractions in VERY small print, with very LARGE caveats in a week or two.

http://www.rushlimbaugh.com/home/daily/site_042910/content/01125113.guest.html

http://www.prisonplanet.com/levin-swat-team-response-to-oil-spill-is-government-takeover-plot.html (Thanks Mark Levin, I see why you and Reagan were such pals)

 

[mgb_phys]

I think that the SWAT acronym has been hijacked over the years to include any situation where a specialized team needs to go in and deal with an unusual problem. Could this be part of the confusion here?

I think that when the Soil and Water Assessment department where trying to think of a cool acronym.

In the UK secret government committees were always named after the room they met in for secrecy.
It's hard to keep an operation secret if you name it "Operation beach landing in Normandy".

The (just about) current government renumbered the offices so that the anti-terrorism committee could meet in room 'A', hence making it "Cabinet Office Briefing Room A" = COBRA team.

 

[Sbrownstein]

PRDAN4th...That too was my first assumption, since oil directly from a well head is generally much warmer than the 40 degree water. However, remember that this orifice is not at the wellhead but is at the end of nearly 5000 feet of abandoned drill riser. This low speed flow would have served to significantly cool the oil before it exits the broken pipe. In addition, since the oil is buoyant, I would expect that the compressed methane that is in the stream first encounters cold water on exiting the pipe and hence forms hydrates as it bubbles through the seawater. I had heard that there was a plan to pump surface water down a concentric pipe to keep the oil flowing. Since surface water at the moment is probably 80 degrees F, a significantly larger pipe should serve to rewarm the oil on the way up. HOWEVER, they will need to torch off the significant volume of methane as soon as the flow reaches the surface, which is commonly done on production platforms. I find it hard to believe that the wellhead is producing water as well, it just doesn't make hydrodynamic sense, especially when the deposit is quite hot and the entire wellhead is under positive pressure.

 

[Frame Dragger]

PRDAN4th...That too was my first assumption, since oil directly from a well head is generally much warmer than the 40 degree water. However, remember that this orifice is not at the wellhead but is at the end of nearly 5000 feet of abandoned drill riser. This low speed flow would have served to significantly cool the oil before it exits the broken pipe. In addition, since the oil is buoyant, I would expect that the compressed methane that is in the stream first encounters cold water on exiting the pipe and hence forms hydrates as it bubbles through the seawater. I had heard that there was a plan to pump surface water down a concentric pipe to keep the oil flowing. Since surface water at the moment is probably 80 degrees F, a significantly larger pipe should serve to rewarm the oil on the way up. HOWEVER, they will need to torch off the significant volume of methane as soon as the flow reaches the surface, which is commonly done on production platforms. I find it hard to believe that the wellhead is producing water as well, it just doesn't make hydrodynamic sense, especially when the deposit is quite hot and the entire wellhead is under positive pressure.

I believe they've aleady given up on heating sea-water, and are considering using an ethanol mixture as antifreeze.

 

[Sbrownstein]

PRDAN4th...Either way, although ethanol is miscible, some sort of antifreeze in the cofferdam to begin with will keep the hydrates from forming until the oil level fills below the drill pipe. After that and with flow established the system should settle down to steady state and as long as they keep the seawater at the bottom of the chamber and away from the methane that is coming out of the pipe. Take the ethanol that is going into my gas tank and pump it down the pipe...even glycol. They should be able to lower the chamber and make sure the instantaneous back pressure matches the water column for every depth. This should work, and if they have a smaller chamber...so be it, although it means that they will have less tolerance on maintaining the level going forward. Just don't bubble the methane through the seawater while they are setting it. Surface water won't hurt to keep the pipe warm, and help the flow, although it won't eliminate hydrate formation as it is not hot enough...but they do have an awful lot of it on the surface anyway.

 

[Sbrownstein]

BY the way, has anyone found any sources of information on what is happening and what they are thinking. I haven't seen any ROV images since the day after the fire and most of the popular press doesn't even understand or write about what they are trying to do. I'm tired of reading about political implications or Obama or Bush. Technology got us into this...and technology will get us out of it!

 

[Cyrus]

SWAT in america means "Special Weapons And Tactics" (or their original name Special Weapons Attack Teams), a part of local police forces for dealing with heavily armed criminals, hostage situations, that sort of thing.


And I'm pretty sure I heard the "A" when he said SWAT.

I'm well aware of what SWAT means (I live in America, BTW), in the police sense. However, that does not mean it is the only acronym that uses those letters.

 

[pallidin]

I think it's good that there have been some clarifications on acronym use.
With a general U.S. public perception that SWAT is a police-only acronym could lead to erroneous speculation on this disaster issue.

Anyway, I hope progress is made to cap or redirect the oil. Haven't checked the news lately.