CR4® - The Engineer's Place for News and Discussion®


Previous in Forum: Dog-Walking Drone   Next in Forum: What are the Top IoT Technologies?
Close
Close
Close
46 comments
Guru
Technical Fields - Technical Writing - New Member Engineering Fields - Marine Engineering - New Member

Join Date: Sep 2008
Location: Vancleave, Ms about 30 miles inland from Biloxi and the coast
Posts: 3062
Good Answers: 103

Proposal For An Undersea Oil Drilling Rig

08/29/2017 8:46 PM

This drilling rig would be totally enclosed and submerged to the sea floor where all of the drilling action would take place. The basic structure would comprise three cylinders of the following approximate dimensions: 20’ diameter x 40’ long. They would be laid out in an upside-down T pattern with the cylinder in the center pointing up and the other two cylinders facing out 90° left and right and 180° apart. Additional cylinders could be added, radiating out from the center cylinder. The ends of the cylinders would be elliptical for strength. The central cylinder would be where the drilling would take place and would communicate to the two outside cylinders by watertight doors. Drill pipe would be stored vertically, soda straw fashion in the central cylinder. A means of replenishing the drill pipe would be accomplished by lowering consumables inside a separate cylinder and would “dock” with the undersea rig similar to space docking. The two outer cylinders would house shops, machinery and rest areas. The cylinders could be fabricated using submarine pressure hull technology. I think the depth this rig could operate at would be established by depths today’s submarines can operate at.

The undersea drill rig would be supplied with air, water, etc from the surface from an anchored barge or barges. Drilling crews would descend and return to the surface each work shift by way of an “escape” capsule and could be housed on the barge as is currently the practice with surface drilling platforms. Once oil starts to flow, it would be transported to the surface through pipes to permanently moored barges where the oil would be loaded unto tankers. Working at deep depths would not be much different than working in underwater tunnel boring machines like those that built the English Channel tunnel.

Not knowing much about oil drilling, I can only present a very rough size estimate. The only number I know is that drill pipe comes in 39 and 45 ft lengths, so maybe the center cylinder would need to be tall enough to accommodate the 45 ft length. I toss this idea out for discussion. I’m sure greater minds than mine can improve on it. Other configurations are possible, like a cylinder within a cylinder.

__________________
Mr.Ron from South Ms.
Register to Reply
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
Guru

Join Date: Mar 2007
Location: at the beach in Florida
Posts: 19222
Good Answers: 1125
#1

Re: Proposal for an Undersea Oil Drilling Rig

08/29/2017 10:19 PM

I used to know a guy that worked on the oil platforms as a diver, they had an underwater habitat that they lived in for , 10 days or a couple of weeks, i forget, but they stayed down there for a long time because of the air mixture they had to breathe and the time to condition from surface to depth...It's hard to find information on though....He made good money, but it was risky....

....but it seems anything that is possible is being done, or off the table for one reason or another....

https://www.pinterest.com/pin/302937512405051333/

__________________
Life is like riding a bicycle. To keep your balance you must keep moving. A.E.
Register to Reply
Guru

Join Date: Jun 2007
Posts: 1049
Good Answers: 40
#20
In reply to #1

Re: Proposal for an Undersea Oil Drilling Rig

08/31/2017 12:43 PM

"...they had an underwater habitat that they lived in for , 10 days or a couple of weeks, i forget, but they stayed down there for a long time..."

[[... a "multi-response" here . . .]]

Such diving operations are referred-to as "Saturation Diving" (because the blood/body tissues become totally saturated with the maximum amount of gas capable of being absorbed)... ergo, the need for "decompression" at the end of the job.

As the OP stated~

"Drilling crews would descend and return to the surface each work shift by way of..." ... diving bells, which "pressure-mate-to" the topside "habitat", allowing divers to remain AT their "working depth" 24/7, for the duration of the job. [They remain & 'live' topside, except while they are "On_Shift", working... they do not remain "down there", except "pressure-wise".]

It used to be that divers could remain "at depth" for many weeks (several months if necessary) at a time.

But, as our knowledge of the long-term-effects has broadened, recent changes to standards mandate that the duration be no longer than 30 days, which must be followed by an equal time "at surface".

A 'principal-effect' from long-term saturation diving is deterioration of the miniscule blood vessels on the back of the retina, of-all-things.

H-PL-Guy's response should be 'promoted' to a "front-position", for its succinct correctness.

(OP) "Additional cylinders could be added..." (perhaps during the initial-design-phase...not likely once installed)

"The ends of the cylinders would be elliptical for strength." Not if they want ME to be in there...(!) They'll spend the money to figure out how to make hemispherical heads, for max-survivability-chance.

The wrong questions are being "thrown-out-there" (within this thread), in attempts to 'negate' the idea proposed....

Sealing the various works involved in offshore oil & gas is a well developed technology, and, the same concepts used in the sealing of "geo-drilling" and pipeline hot-tapping (pdf)/{YouTube} are easily applied to the "docking / undocking" of either personnel or supplies for such a venture.

I wonder whether "MACA" {"GA"} spent any time working alongside a "Mud Engineer". The major "sealing problem" to be addressed, as I see it, would NOT relate to the habitat itself, but rather to the drilling column.

It is a tricky business, determining just how much "heavyweight drilling mud additives" needs to be introduced / added-to the drilling-hydraulics, to insure a sufficiently heavy column of mud being maintained on top of drilling activities, so as to help prevent "blowouts"... (one of the first such events)

Another kind of "blowout"... 1/2 mile of drill string in a "rats-nest" blown 2000 ft in the air!

Photos courtesy of (scanned-from) "Adventure in Oil" (historical docu-drama of the birth and growth of BP)

Register to Reply
Guru

Join Date: Apr 2011
Posts: 6547
Good Answers: 241
#22
In reply to #20

Re: Proposal for an Undersea Oil Drilling Rig

08/31/2017 3:36 PM

Okay, so I am ignorant of the workings of drilling rigs. You seem sufficiently assured in your knowledge to say there is no problem in passing items from the working space to the water at 1,000s of psi greater pressure without flooding .

Would you be so kind as to explain. How large objects might have maintenance inspections and repair performed in the low pressure human space and be returned to the high pressure side without garganuan airlocks?

What am I missing here? I lived aboard a sub for a few years and even the thoughts of smaller seals at pressures lower than that would concern me.

__________________
Eternal vigilance is the price of knowledge. - George Santayana
Register to Reply
Guru

Join Date: Jun 2007
Posts: 1049
Good Answers: 40
#25
In reply to #22

Re: Proposal for an Undersea Oil Drilling Rig

08/31/2017 5:12 PM

"Oh dear"...

"Would (I) be so kind as to explain. How large objects might have maintenance inspections and repair performed in the low pressure human space and be returned to the high pressure side without gargantuan airlocks?"

"Apologies", but, I don't seem to be on the same wavelength, with regard to "why", this question.... (allow me to "recap"):

MACA (#4) had stated:

"To try and add the drill rig and people down there would be pretty much impossible right now."

to which redfred had replied:

"{GA!}...the only advantage I see of putting people at these depths to drill for anything is that troubleshooting inspections, decisions and repairs might be possible without worrying about tangling communication lines to the surface"

...to which YOU had replied:

"I really don't see how 'troublesome inspections, repairs, and decisions' might be made easier, or even just practical", adding comments regarding "seals-in-general" ("water-vs-air", as I had read it).

The portion of my comment regarding "seals" was simply noting the fact that subsea engineers have (literally) perfected the art of sealing the boundaries between water/gas/oil/air... (in pipelines/production etc).

The "trick" not addressed by the OP was...('uh', did you access the photos that I linked-to?, above)...

let me go at it a different way:

scrutinize the 2nd page, of this 2-pg "spec-synopsis"

Where will the thousands of barrels of "drilling mud" (and Barite or other "weight additive") be kept in this cylindrical contraption...?(!) And how-on-earth will an adequate protective column of "weight-mud" be *maintained* on this seafloor_level "rig"...?

The potential pressures within subsea reservoirs can be astronomical.

[I have been "suited-up", in dive-hat; the "dope-on-a-rope" inspecting a drill-rig mat on-bottom, WHILE the unit was drilling...and that was "scary enough".]

I cannot imagine anybody wanting to be in a "hunk-o'-pipe"/"submarine-hull", tapping-into a reservoir at, say, 20,000+ ft beneath the seafloor, packing 18k psi at 275F...(!)

[above are typical specs, for example, for the Thunder Horse project, G.O.M.] Docking a "submarine", horizontally OR vertically, to the TOP of the "proposed" subsea "rig", to deliver {or remove} supplies would be NO harder than docking and transferring to the ISS (even though THAT would be a "small potatoes" pressure differential, a poor comparison at best). Keeping men, inside such a rig, "safe-and-sane", knowing what they were doing, would be a whole different matter....

Register to Reply
Guru

Join Date: Apr 2011
Posts: 6547
Good Answers: 241
#26
In reply to #25

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 4:22 AM

"...The portion of my comment regarding "seals" was simply noting the fact that subsea engineers have (literally) perfected the art of sealing the boundaries between water/gas/oil/air... (in pipelines/production etc). ..."

.

Okay, thanks. That clears up a lot. We aren't talking about the same thing.

You are talking about maintaining boundaries in actual production, say for drilling fluid for example.

I am talking about doing maintenance/repair on a largepiece of equipment in a human accessable area, and then atattempting to move the equipment from atmospheric to the great pressure just outside the bulkhead without ginormous airlock or flooding.

Imagine either using coiled pipe, or joining pipe lengths to extend downward below the bottom of the workspace, in either case, the sliding seals would have to be phenomenal.

__________________
Eternal vigilance is the price of knowledge. - George Santayana
Register to Reply
Guru

Join Date: Jun 2007
Posts: 1049
Good Answers: 40
#32
In reply to #26

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 9:31 AM

"Ahhh"... re-reading your Post#4 (in the context now stated), I see how I had read it a bit differently. We are on the same wavelength, seeing the same problem (with the proposed concept)... just from slightly different perspectives.

In "PVHO-speak" (Pressure Vessels for Human Occupancy), the locks that you referred to are "T.U.P's" (Transfer Under Pressure). And, "yes", there would be a need for several of these, of incredible / GINORMOUS proportions...(!)

Register to Reply
Guru
Safety - Hazmat - New Member United States - US - Statue of Liberty - New Member Engineering Fields - Chemical Engineering - Old Hand

Join Date: Mar 2011
Location: Lubbock, Texas
Posts: 13438
Good Answers: 152
#35
In reply to #32

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 10:43 AM

Instead of oil exploration and drilling this way (outmoded before it starts), I think the mining of mineral deposits on the ocean floor, such as manganese nodules is also an area where human workers might out do the robots for a time. Although, already most of the nodules collection and exploration is done by deep sea robotics.

Some environments are just not facile for human occupancy, plain and simple. Far easier to condition harden a robot, and send it in there.

__________________
If it ain't broke, don't fix it. Just build a better one.
Register to Reply Score 1 for Good Answer
Guru

Join Date: Oct 2008
Posts: 39875
Good Answers: 1587
#2

Re: Proposal for an Undersea Oil Drilling Rig

08/29/2017 10:31 PM

This will not be necessary any time soon. The new administration is rolling back environmental protections and is going to allow drilling in shallow, coastal waters and in some national parks/monuments so there will be no need for deep water drilling in our lifetimes.

If it were feasible, and cost effective someone would already be doing it. Getting the drill stems from the surface to the wellhead would be a big challenge. Pulling them to replace a drill bit would be monumental.

Perhaps, in 40 years the technology will advance to a point where robots can work under 10,000 feet of salt water.

Register to Reply Score 2 for Off Topic
Guru
Safety - Hazmat - New Member United States - US - Statue of Liberty - New Member Engineering Fields - Chemical Engineering - Old Hand

Join Date: Mar 2011
Location: Lubbock, Texas
Posts: 13438
Good Answers: 152
#10
In reply to #2

Re: Proposal for an Undersea Oil Drilling Rig

08/30/2017 2:08 PM

Don't worry, Lyn, someone smarter than us has already thought about this, and will find a way to produce 10 times that amount from deep-water rigs.

So, see, there's nothing to worry about. Be happy!

That is all I want for you and me, is to be happy, and know that God is still in control, and everything is going just as it should be. Don't worry, be happy!

__________________
If it ain't broke, don't fix it. Just build a better one.
Register to Reply Off Topic (Score 4)
Guru
Hobbies - Musician - Engineering Fields - Chemical Engineering - New Member Engineering Fields - Control Engineering - New Member Engineering Fields - Instrumentation Engineering - New Member

Join Date: Jan 2007
Location: Moses Lake, WA, USA, Thulcandra - The Silent Planet (C.S. Lewis)
Posts: 3929
Good Answers: 174
#16
In reply to #10

Re: Proposal for an Undersea Oil Drilling Rig

08/31/2017 2:29 AM

That, my friend is a Russian t-shirt. The phrase on the shirt is: "I'M PETROLEUM ENGINEER just like..."

Russian-american translation dialect often leaves conjunctions out of phrases and sentences.

In this case, it doesn't say: "I'M A PETROLEUM ENGINEER". But, it leaves out the 'A'.

So, it is of Russian origin, or......

...

...

...

...

...

... it was produced by millennials, many of which don't "do" English well.

__________________
"Reason is not automatic. Those who deny it cannot be conquered by it. Do not count on them. Leave them alone." - Ayn Rand
Register to Reply Off Topic (Score 4)
Guru
Safety - Hazmat - New Member United States - US - Statue of Liberty - New Member Engineering Fields - Chemical Engineering - Old Hand

Join Date: Mar 2011
Location: Lubbock, Texas
Posts: 13438
Good Answers: 152
#17
In reply to #16

Re: Proposal for an Undersea Oil Drilling Rig

08/31/2017 9:08 AM

Nyet, I tell you for fact, this tee shirt nuthing to do with Mother Russia. It not soaked in wodka, or the ink smeared all over. Everyone in Russia same intellect, nobody think that way in Russia. Why Ameriki always blame patriotic, peace-loving Russian for everything?

__________________
If it ain't broke, don't fix it. Just build a better one.
Register to Reply
Guru
Hobbies - CNC - New Member Hobbies - DIY Welding - New Member Engineering Fields - Electromechanical Engineering - New Member

Join Date: Aug 2007
Posts: 18946
Good Answers: 336
#19
In reply to #2

Re: Proposal for an Undersea Oil Drilling Rig

08/31/2017 10:36 AM

If it were feasible, and cost effective someone would already be doing it.

Someone will, they always do...

Keep this in mind... I recall back in the 60's that we should have run out of oil already... as time marches on, so has technology...

OIL SUPPLY UPDATE Revised

We will now run out of oil in 50 years...

I'll keep you posted with up dates and revisions..

__________________
phoenix911
Register to Reply
Anonymous Poster #1
#27
In reply to #19

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 5:00 AM

50 years was reported in your attached article which was published in 2014 and as far as I am aware was based on 2012/13 data. We will have oil reserves in hundreds of years time. Economics will decide how hard we look for it and how much we spend on getting it out of the ground. In the 1970/80s the conventional wisdom was that we would run out of oil in 30 odd years - Yeah - fake news.

Register to Reply
Guru
Hobbies - CNC - New Member Hobbies - DIY Welding - New Member Engineering Fields - Electromechanical Engineering - New Member

Join Date: Aug 2007
Posts: 18946
Good Answers: 336
#28
In reply to #27

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 7:12 AM

We will have oil reserves in hundreds of years time. Economics will decide how hard we look for it and how much we spend on getting it out of the ground.

Hence my point to my post in response to lyn...

__________________
phoenix911
Register to Reply
Guru
Safety - Hazmat - New Member United States - US - Statue of Liberty - New Member Engineering Fields - Chemical Engineering - Old Hand

Join Date: Mar 2011
Location: Lubbock, Texas
Posts: 13438
Good Answers: 152
#29
In reply to #28

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 8:42 AM

I think it was only last year, the subject arose where geologist believe they have discovered deep, deep natural gas, near the crustal-mantle boundary, and now there appears to be a physical-chemical mechanism for the origin of this methane, no biology required. The resource itself seems to be "renewing" itself over a time period not inconsistent with human requirements.

The question will end up being how to shove or capture the CO2 from combustion to prevent ever higher concentrations in the atmosphere, even though the oceans can naturally take-up huge amounts, and so can tropical forested areas (if we don't chop them all down).

Once again, I believe the Earth is trying to be "generous" to humanity, rather than stingy.

__________________
If it ain't broke, don't fix it. Just build a better one.
Register to Reply
Guru
Hobbies - CNC - New Member Hobbies - DIY Welding - New Member Engineering Fields - Electromechanical Engineering - New Member

Join Date: Aug 2007
Posts: 18946
Good Answers: 336
#30
In reply to #29

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 8:51 AM

Once again, I believe the Earth is trying to be "generous" to humanity, rather than stingy.

I, myself feel the earth is indifferent to humanity as to whether it will be a part of its future,... or not. And just become additional hydrocarbons for the earths reserves.

__________________
phoenix911
Register to Reply
Guru
Engineering Fields - Electrical Engineering - Been there, done that, still doing it. Engineering Fields - Control Engineering - New Member

Join Date: Dec 2008
Location: Long Island NY
Posts: 12216
Good Answers: 774
#31
In reply to #30

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 9:13 AM

Yes. Life will certainly continue for a long time on this blue spinning marble. I'm just not sure how long humanity will be part of that life. The question has always been how long until our excrement kills us.

Life on Earth will last longer than my lifetime. Also, I have no children nor does my only sibling.

DILLIGAF

__________________
"Don't disturb my circles." translation of Archimedes last words
Register to Reply
Guru
Safety - Hazmat - New Member United States - US - Statue of Liberty - New Member Engineering Fields - Chemical Engineering - Old Hand

Join Date: Mar 2011
Location: Lubbock, Texas
Posts: 13438
Good Answers: 152
#34
In reply to #31

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 10:40 AM

Well, redfred, no, actually you don't look like that at all, I am thinking somewhere in the territory less than a F.

Last time I checked, excrement is usually handled by aerobic and anaerobic processes in water "reclamation" plants. At least in our generation we provide that courtesy before we "pull the chain and give Oklahoma City a drink". That was a sign in service station restroom back during the Model A era on a highway west of the aforementioned city located on the Canadian River. These days we shudder, and wonder in amazement how that generation survived all the encumbrances we now avoid.

__________________
If it ain't broke, don't fix it. Just build a better one.
Register to Reply
Guru
Engineering Fields - Electrical Engineering - Been there, done that, still doing it. Engineering Fields - Control Engineering - New Member

Join Date: Dec 2008
Location: Long Island NY
Posts: 12216
Good Answers: 774
#36
In reply to #34

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 11:13 AM

If only all of excrement was biologic.

Remember, I work with radiation on a daily basis and this just sickens me.

__________________
"Don't disturb my circles." translation of Archimedes last words
Register to Reply
Guru
Safety - Hazmat - New Member United States - US - Statue of Liberty - New Member Engineering Fields - Chemical Engineering - Old Hand

Join Date: Mar 2011
Location: Lubbock, Texas
Posts: 13438
Good Answers: 152
#37
In reply to #36

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 11:20 AM

rightfully so. How come we do not get on it with the LIFTR (or other reactor) that can eat the left-over fuel for breakfast? The low-level stuff is supposed to be buried in salt caverns down near Carlsbad, NM, some higher level stuff goes in out by Andrews, TX, and then there was that place in Nevada the politicians keep putting off, due to lawsuits from various groups whose purpose seems to the be the acceleration of all our demise.

__________________
If it ain't broke, don't fix it. Just build a better one.
Register to Reply
Guru
Engineering Fields - Electrical Engineering - Been there, done that, still doing it. Engineering Fields - Control Engineering - New Member

Join Date: Dec 2008
Location: Long Island NY
Posts: 12216
Good Answers: 774
#38
In reply to #37

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 12:12 PM

I don't wish to hijack this thread anymore than necessary but I will try to briefly answer your question.

IMHO The root cause why nuclear waste is only handled by (marginally) controlled abandonment is a combination of irrational fear of science/engineering and NIMBY.

The one proposed but rejected nuclear waste mitigation I liked was a modification of a LWR by the addition of a proton accelerator to transmute and accelerate the decay rate of spent fuel. This process would produce more usable heat energy than the energy consumed by the accelerator but naturally not as much as the former reactor once did produce. However, this proposal used spent fuel without any reprocessing. It also is a re-purposing retrofit of (one of) the reactor(s) that produced the spent fuel in the first place, no transportation worries.

I admit that this maybe a too good to be completely true proposal but don't all improvements start this way.

__________________
"Don't disturb my circles." translation of Archimedes last words
Register to Reply
Guru
Safety - Hazmat - New Member United States - US - Statue of Liberty - New Member Engineering Fields - Chemical Engineering - Old Hand

Join Date: Mar 2011
Location: Lubbock, Texas
Posts: 13438
Good Answers: 152
#39
In reply to #38

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 12:24 PM

I really like the concept. Understandably, I ask how thermally stable is the process?

Similar situation with moderators and control rods?

__________________
If it ain't broke, don't fix it. Just build a better one.
Register to Reply
Guru
Engineering Fields - Electrical Engineering - Been there, done that, still doing it. Engineering Fields - Control Engineering - New Member

Join Date: Dec 2008
Location: Long Island NY
Posts: 12216
Good Answers: 774
#40
In reply to #39

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 2:30 PM

Turning the proton beam OFF stops the sub-critical fission and transmutation reaction. Decay radiation still happens but this still happens in a moderated critical reaction, too.

As for thermal stability, it's not stable at all. That's why it produces power. However, unlike a normal fission pile it cannot run away.

__________________
"Don't disturb my circles." translation of Archimedes last words
Register to Reply
Guru
Safety - Hazmat - New Member United States - US - Statue of Liberty - New Member Engineering Fields - Chemical Engineering - Old Hand

Join Date: Mar 2011
Location: Lubbock, Texas
Posts: 13438
Good Answers: 152
#41
In reply to #40

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 3:11 PM

Sounds plenty easy to switch it off in a disaster! Proton beams not that "wild" in nature. Kinda like turning off the "stove", isn't it?

__________________
If it ain't broke, don't fix it. Just build a better one.
Register to Reply
Guru

Join Date: Apr 2011
Posts: 6547
Good Answers: 241
#42
In reply to #38

Re: Proposal for an Undersea Oil Drilling Rig

09/02/2017 10:04 PM

It sounds great when you put it that way: transmutation by cheap conversion of an existing LWR that continues to produce power as it make waste less dangerous.

Getting a proton beam with required energy (~1GeV+) to all the necessary places safely as a retrofit to an existing LWR has some hurdles that seem insurmountable.

LWR are pressurized. I am just making as assumption here, but the equipment that creates the proton beam will be outside of the pressure vessle, right? That requires traversing the pressure vessle wall and the cladding as well with a beam that is going to cause material transmutation and likely induce hydrogen embrittlement in succeptable materials. That will be highly problematic.

Another problem would likely be the energy gains. Do you have any links for studies about net energy production by transmuting transuranics with proton beams? Doesn't seem likelyeven with a purpose built system, much less a LWR retrofit.

.

I do like this line of thinking though.

.

I suspect more benefit might be available with similar minimization of reprocessing via retrofit of a LWR with a neutron beam. Still has some problems traversing the pressure vessle and cladding, and I doubt there will be a huge reduction in transuranics, but if the power squeezed from fuel rods can be increased significantly, then the volume of unprocessed waste is greatly reduced.

__________________
Eternal vigilance is the price of knowledge. - George Santayana
Register to Reply
Guru
Engineering Fields - Electrical Engineering - Been there, done that, still doing it. Engineering Fields - Control Engineering - New Member

Join Date: Dec 2008
Location: Long Island NY
Posts: 12216
Good Answers: 774
#44
In reply to #42

Re: Proposal for an Undersea Oil Drilling Rig

09/03/2017 7:17 PM

Alas the only paper I read about this approach was just a feasibility proposal from many years back. Most of the theoretical part of the paper delved into the nominal isotopes in spent rods and the proton energies needed to transmute these isotopes. I do remember the engineering part of the proposal had the reaction site not pressurized. A lot of the retrofitting was to get this low energy rate of release (compared to the LWR) into usable power. It was not a major power producer but more of a waste mitigation plan.

__________________
"Don't disturb my circles." translation of Archimedes last words
Register to Reply
Guru
Safety - Hazmat - New Member United States - US - Statue of Liberty - New Member Engineering Fields - Chemical Engineering - Old Hand

Join Date: Mar 2011
Location: Lubbock, Texas
Posts: 13438
Good Answers: 152
#45
In reply to #42

Re: Proposal for an Undersea Oil Drilling Rig

09/05/2017 1:35 PM

Would it not be more readily accomplished with a non-pressurized reactor, a molten salt design, where the only pressurized portion is the salt/water heat exchanger (secondary loop, not the primary loop, as that one is salt/salt heat exchanger).

__________________
If it ain't broke, don't fix it. Just build a better one.
Register to Reply
Guru

Join Date: Apr 2011
Posts: 6547
Good Answers: 241
#46
In reply to #45

Re: Proposal for an Undersea Oil Drilling Rig

09/07/2017 3:25 AM

I suspect it would, especially if protons were to be the particles striking the targets for transmutation. The walls of any high temps pressure vessel would be problematic with a large flux of high energy protons crossing.

I was typing out loud about the suggestion of a lightly modified LWR being used to improve waste using fast protons.

It seems like even if fast proton are used, neutrons will still be produced so things will still become activated and additional transurancis will be formed unless processing is performed to separate fuel into constituents.

Seems like providing a strong neutron source late in fuel life to offset poison accumulation/excess negative reactivity would allow more complete burn up...less waste per kW-hr. Transuranics still need a long term plan, but there could be far less overall to deal with. This may be possible with limited modification of an existing LWR.

__________________
Eternal vigilance is the price of knowledge. - George Santayana
Register to Reply
Guru

Join Date: Apr 2011
Posts: 6547
Good Answers: 241
#43
In reply to #36

Re: Proposal for an Undersea Oil Drilling Rig

09/02/2017 10:13 PM

Are those the one-ear-up, tailless, double-dew-claw dogs of Chernobyl?

__________________
Eternal vigilance is the price of knowledge. - George Santayana
Register to Reply
Guru

Join Date: Apr 2011
Posts: 6547
Good Answers: 241
#3

Re: Proposal for an Undersea Oil Drilling Rig

08/29/2017 11:17 PM

Okay, how do you get the pipe and drilling equipment out of the people space without water rushing in?

Those would be some very nifty sliding seals.

.

Also, if the people are going to be able to return to the surface after every shift, the work space needs to be near atmospheric pressure at sea level, right? Those are going to be some seriously thick walls.

.

Heat is going to be an issue, surrounded by 0° flowing water. Some serious insulation will probably force the diameter of the work space cylinders to be even larger to be adequate for work.

.

Really, those last two are not necessarily show stoppers, but tell me more about how things worked on in the space gets transfered into the sea bed without 1000+ psig water inviting itself in.

__________________
Eternal vigilance is the price of knowledge. - George Santayana
Register to Reply
8
Power-User

Join Date: Feb 2007
Location: Aberdeen, Scotland
Posts: 346
Good Answers: 17
#4

Re: Proposal for an Undersea Oil Drilling Rig

08/30/2017 2:19 AM

I work as a subsea engineer and we spend a lot of time and money in developing technology which enables us to safely transport hydrocarbons from the well to surface without having to put people on the sea bed. Until you actually work in this field it is probably quite hard to understand the scale of the problems we face. Subsea trees weigh anything up to 120 tonnes. Manifolds to tie back jumpers weigh more. I've seen a design for manifold which was 500 tonnes.

These pieces of kit are only for allowing the safe transport of oil/gas. To try and add the drill rig and people down there would be pretty much impossible right now. The cost would cripple the national budget of many countries. At 10,000 ft water depth (which is a common requirement) the hydrostatic forces are enormous. Add to that the dangers which are already present on drilling rigs (blow outs, hydrates, heavy plant) you would be suicidal to want to try that at 10,000 ft below.

Now I've said that someone will probably do it, but I can't see the advantages, only real big problems.

Register to Reply Good Answer (Score 8)
Guru
Engineering Fields - Electrical Engineering - Been there, done that, still doing it. Engineering Fields - Control Engineering - New Member

Join Date: Dec 2008
Location: Long Island NY
Posts: 12216
Good Answers: 774
#6
In reply to #4

Re: Proposal for an Undersea Oil Drilling Rig

08/30/2017 11:37 AM

Great answer!

With today's technology, the only advantage I see of putting people at these depths to drill for anything is that troubleshooting inspections, decisions and repairs might be possible without worrying about tangling communication lines to the surface. Since getting communication to these depths is trivial compared to the cost and complications of lowering the drilling rig to these depths this is making things harder instead of easier.

__________________
"Don't disturb my circles." translation of Archimedes last words
Register to Reply
Guru

Join Date: Apr 2011
Posts: 6547
Good Answers: 241
#14
In reply to #6

Re: Proposal for an Undersea Oil Drilling Rig

08/30/2017 11:53 PM

I really don't see how 'troublesome inspections, repairs, and decisions' might be made easier, or even just practical.

Sure you might be physically close, but without some crazy all encompassing lock system, or the most robust adaptable seals ever, the proximity doesn't get you any closer to being able to inspect or work on equipment at that depth that isn't in the people space.

__________________
Eternal vigilance is the price of knowledge. - George Santayana
Register to Reply
Guru
Engineering Fields - Electrical Engineering - Been there, done that, still doing it. Engineering Fields - Control Engineering - New Member

Join Date: Dec 2008
Location: Long Island NY
Posts: 12216
Good Answers: 774
#18
In reply to #14

Re: Proposal for an Undersea Oil Drilling Rig

08/31/2017 9:08 AM

That is precisely my point. The only tiny plausible advantage I can think of is greatly overwhelmed by all of the complications required to attempt this minuscule advantage.

__________________
"Don't disturb my circles." translation of Archimedes last words
Register to Reply
Guru

Join Date: Apr 2010
Posts: 5744
Good Answers: 576
#7
In reply to #4

Re: Proposal for an Undersea Oil Drilling Rig

08/30/2017 12:14 PM

Yup, 10000 ft is 4500 psi, not easy to work with, bad place for humans...

Register to Reply
Guru
Engineering Fields - Instrumentation Engineering - EE from the the Wilds of Pa.

Join Date: Feb 2006
Location: middle of nowhere, Pennsylvania
Posts: 2495
Good Answers: 58
#33
In reply to #4

Re: Proposal for an Undersea Oil Drilling Rig

09/01/2017 9:38 AM

There is one rather important advantage - lack of wave action. Sitting out a passing hurricane would be a bit easier way below the surface than above the surface. I'm sure the waters get stirred a bit below the surface, but nothing like on the surface.

Now I doubt that one thing, that may never occur, out weighs all the other negatives you've mentioned.

__________________
Remember when reading my post: (-1)^½ m (2)^½
Register to Reply
Guru
Hobbies - Musician - Engineering Fields - Chemical Engineering - New Member Engineering Fields - Control Engineering - New Member Engineering Fields - Instrumentation Engineering - New Member

Join Date: Jan 2007
Location: Moses Lake, WA, USA, Thulcandra - The Silent Planet (C.S. Lewis)
Posts: 3929
Good Answers: 174
#5

Re: Proposal For An Undersea Oil Drilling Rig

08/30/2017 10:39 AM

The depth of the installation will reveal what thickness the walls of the cylinders need to be to prevent implosion.

At a depth of 1000 ft, your installation must withstand 440 psi.

__________________
"Reason is not automatic. Those who deny it cannot be conquered by it. Do not count on them. Leave them alone." - Ayn Rand
Register to Reply
Guru
Engineering Fields - Electrical Engineering - New Member Fans of Old Computers - Commodore 64 - New Member Popular Science - Evolution - New Member United States - Member - New Member

Join Date: Oct 2013
Location: Illinois, 7 county region (The 'blue dot' that drags the rest of the 'red state' around during presidential elections.)
Posts: 3488
Good Answers: 87
#8

Re: Proposal For An Undersea Oil Drilling Rig

08/30/2017 1:31 PM

"Drilling crews would descend and return to the surface each work shift by way of an “escape” capsule and could be housed on the barge as is currently the practice with surface drilling platforms."

You're going to subject the workers to a full compress/decompression cycle EVERY DAY just so they can sleep for a few hours before they have to get in the pod and go back down? You are aware that decompression sickness does not occur at depth, but CAN occur when ascending from depth. You're also going to be using a lot of their time in the slow daily ascent and decent.

"Working at deep depths would not be much different than working in underwater tunnel boring machines like those that built the English Channel tunnel."

Yes, and that was hard, dangerous work as well, We used to call the Bands by another name Caison's disease, as it was the caison workers, who did not get proper decompression time when exiting the high-pressure worksite for the lower pressure of the 'regular world.' And I haven't even BEGUN to talk about the risks of a wellhead explosion, like the one at the Deepwater Horizon.

__________________
( The opinions espressed in this post may not reflect the true opinions of the poster, and may not reflect commonly accepted versions of reality. ) (If you are wondering: yes, I DO hope to live to be as old as my jokes.)
Register to Reply
Guru
Safety - Hazmat - New Member United States - US - Statue of Liberty - New Member Engineering Fields - Chemical Engineering - Old Hand

Join Date: Mar 2011
Location: Lubbock, Texas
Posts: 13438
Good Answers: 152
#9

Re: Proposal For An Undersea Oil Drilling Rig

08/30/2017 1:59 PM

We can go ahead and reduce the height requirements if this new rig uses the spool drilling tube they use these days. Seriously, when I first saw steel drill tubing rolled up on a giant spool on an eighteen wheeler with all the gear for winding and unwinding it, I totally wigged out!

Great stuff is out there.

Essentially, ten years ago they were already doing this in the Gulf of Mexico with one of the platform building engineering companies a dear friend of mine was working for.

He was the QC/QA man on what he called the "100-story beer can" - made of a marine noncorrosive alloy - might as well be Unobtainium for the cost, but build it they did, and it was one of the largest platforms. One of my wife's brother-in-laws essentially was the very first to build offshore platforms based on some hair-brained ideas he cobbled together. That is what a welder with time on his hands, and a lot of beer can do. In Texas and Louisiana you can hear it on any given day (mostly Saturday and/or Sunday afternoons): "Here, sonny, hold my beer, and watch this!"

One question: So what happens when you get a fire started in this drill tower resting on the ocean floor? It goes KA-BOOM! You know why? Because if they just pump air into the thing until they beat hydrostatic head, the partial pressure of oxygen will be several atmospheres, most likely. They would have to modify the atmosphere down under, or lose the whole thing the first sign of trouble.

__________________
If it ain't broke, don't fix it. Just build a better one.
Register to Reply Score 1 for Good Answer
2
Active Contributor

Join Date: Dec 2016
Posts: 14
Good Answers: 2
#11

Re: Proposal For An Undersea Oil Drilling Rig

08/30/2017 10:34 PM

Present technology used in Deepwater drilling and subsea wellhead equipment and hydrocarbon production and delivery represents the best balance of economics, technical feasibility and risk. All subsea tasks are performed using robotics and/or remote telemetry. There is absolute zero justification to put a human at risk by exposure to such conditions, not to mention the technical limits of hyperbaric diving technology. The industry has evolved decades ago from such notions. Suggest you pick up a copy of Offshore magazine or Oil and Gas Journal and maybe attend an Offshore Technology Conference and get a better idea as to where the state of the art lies at present. Or alternatively any undergraduate textbook on offshore technology and/or subsea engineering. Your post appears largely as some form of patent application and doesn't really pose any realistic question. That apart from coming from any frame of reference semblant of reality.

Register to Reply Good Answer (Score 2)
Guru
Hobbies - Musician - Engineering Fields - Chemical Engineering - New Member Engineering Fields - Control Engineering - New Member Engineering Fields - Instrumentation Engineering - New Member

Join Date: Jan 2007
Location: Moses Lake, WA, USA, Thulcandra - The Silent Planet (C.S. Lewis)
Posts: 3929
Good Answers: 174
#13
In reply to #11

Re: Proposal For An Undersea Oil Drilling Rig

08/30/2017 11:02 PM

I thought that was a very good and interesting answer. Thank you.

__________________
"Reason is not automatic. Those who deny it cannot be conquered by it. Do not count on them. Leave them alone." - Ayn Rand
Register to Reply
2
Guru

Join Date: Mar 2012
Location: Out of your mind! Not in sight!
Posts: 3977
Good Answers: 92
#12

Re: Proposal For An Undersea Oil Drilling Rig

08/30/2017 11:00 PM

If you want to check out options for that technology just look at what the Norwegians are doing. Always good for a surprise.

http://www.seabedrig.no/files/sbr-artikkel-oilgas.pdf

https://www.marinetechnologynews.com/blogs/future-trends-e28093-automated-drilling-700493

__________________
Common Sense Dictates
Register to Reply Good Answer (Score 2)
Anonymous Poster #1
#15

Re: Proposal For An Undersea Oil Drilling Rig

08/30/2017 11:59 PM

Sub-sea drilling and compression etc. is alive and well, but only as fully automated designs - as others have said, manning them is just not a great option.

Register to Reply
Guru
Engineering Fields - Instrumentation Engineering - EE from the the Wilds of Pa.

Join Date: Feb 2006
Location: middle of nowhere, Pennsylvania
Posts: 2495
Good Answers: 58
#21

Re: Proposal For An Undersea Oil Drilling Rig

08/31/2017 3:24 PM

The problem I see here is the overall height. In deep well drilling, a "triple" rig is used, not a "single" as you are referring to. The reason is when they need to service the bit, they only break every third joint and stand the pipe in the rig (called a "stand") to save time. This occasionally leads to some spectacular failures if the pipe stand shifts and topples, but usually it is quite safe. I only remember this happening once on a rig where I was stationed in 11 years in the "oil patch". Now can you imagine that happening in an enclosed drilling rig under a thousand feet of water? Scares me and nothing scares me.

__________________
Remember when reading my post: (-1)^½ m (2)^½
Register to Reply
Guru
Safety - Hazmat - New Member United States - US - Statue of Liberty - New Member Engineering Fields - Chemical Engineering - Old Hand

Join Date: Mar 2011
Location: Lubbock, Texas
Posts: 13438
Good Answers: 152
#23
In reply to #21

Re: Proposal For An Undersea Oil Drilling Rig

08/31/2017 3:38 PM

Why have joints at all when the drill pipe can coil up these days?

__________________
If it ain't broke, don't fix it. Just build a better one.
Register to Reply
Guru
Engineering Fields - Instrumentation Engineering - EE from the the Wilds of Pa.

Join Date: Feb 2006
Location: middle of nowhere, Pennsylvania
Posts: 2495
Good Answers: 58
#24
In reply to #23

Re: Proposal For An Undersea Oil Drilling Rig

08/31/2017 3:52 PM

Haven't seen that. I've been out of the oil patch for 30 years now. Only triples I've seen since then were the ones that drilled 5 shale wells within 15 miles of my house about 6 years ago. Two were only 2 miles as the crow flies. They still had stands of pipe and pipe tubs.

That was a strange feeling to go watch that knowing I wasn't "next up" once they pulled the stand of pipe. (well logging engineer for 11 years)

__________________
Remember when reading my post: (-1)^½ m (2)^½
Register to Reply
Register to Reply 46 comments
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
Copy to Clipboard

Users who posted comments:

adreasler (1); Anonymous Poster (2); Horhey PL Guy (1); IdeaSmith (1); James Stewart (11); lyn (1); MACA (1); Mikerho (3); ndt-tom (3); phoenix911 (3); Phys (3); redfred (7); Rixter (1); SolarEagle (1); truth is not a compromise (7)

Previous in Forum: Dog-Walking Drone   Next in Forum: What are the Top IoT Technologies?

Advertisement