Oil slick
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Master slacker
Something awesome.
You may have heard the news in the last two days about the Deepwater Horizon drilling rig which caught fire, burned for two days, then sank in 5,000 ft of water in the Gulf of Mexico. There are still 11 men missing, and they are not expected to be found.
The rig belongs to Transocean, the world’s biggest offshore drilling contractor. The rig was originally contracted through the year 2013 to BP and was working on BP’s Macondo exploration well when the fire broke out. The rig costs about $500,000 per day to contract. The full drilling spread, with helicopters and support vessels and other services, will cost closer to $1,000,000 per day to operate in the course of drilling for oil and gas. The rig cost about $350,000,000 to build in 2001 and would cost at least double that to replace today.
The rig represents the cutting edge of drilling technology. It is a floating rig, capable of working in up to 10,000 ft water depth. The rig is not moored; It does not use anchors because it would be too costly and too heavy to suspend this mooring load from the floating structure. Rather, a triply-redundant computer system uses satellite positioning to control powerful thrusters that keep the rig on station within a few feet of its intended location, at all times. This is called Dynamic Positioning.
The rig had apparently just finished cementing steel casing in place at depths exceeding 18,000 ft. The next operation was to suspend the well so that the rig could move to its next drilling location, the idea being that a rig would return to this well later in order to complete the work necessary to bring the well into production.
It is thought that somehow formation fluids – oil /gas – got into the wellbore and were undetected until it was too late to take action. With a floating drilling rig setup, because it moves with the waves, currents, and winds, all of the main pressure control equipment sits on the seabed – the uppermost unmoving point in the well. This pressure control equipment – the Blowout Preventers, or ‘BOP’s” as they’re called, are controlled with redundant systems from the rig. In the event of a serious emergency, there are multiple Panic Buttons to hit, and even fail-safe Deadman systems that should be automatically engaged when something of this proportion breaks out. None of them were aparently activated, suggesting that the blowout was especially swift to escalate at the surface. The flames were visible up to about 35 miles away. Not the glow – the flames. They were 200 – 300 ft high.
All of this will be investigated and it will be some months before all of the particulars are known. For now, it is enough to say that this marvel of modern technology, which had been operating with an excellent safety record, has burned up and sunk taking souls with it. The well still is apparently flowing oil, which is appearing at the surface as a slick. They have been working with remotely operated vehicles, or ROV’s which are essentially tethered miniature submarines with manipulator arms and other equipment that can perform work underwater while the operator sits on a vessel. These are what were used to explore the Titanic, among other things. Every floating rig has one on board and they are in constant use. In this case, they are deploying ROV’s from dedicated service vessels. They have been trying to close the well in using a specialized port on the BOP’s and a pumping arrangement on their ROV’s. They have been unsuccessful so far. Specialized pollution control vessels have been scrambled to start working the spill, skimming the oil up.
In the coming weeks they will move in at least one other rig to drill a fresh well that will intersect the blowing one at its pay zone. They will use technology that is capable of drilling from a floating rig, over 3 miles deep to an exact specific point in the earth – with a target radius of just a few feet plus or minus. Once they intersect their target, a heavy fluid will be pumped that exceeds the formation’s pressure, thus causing the flow to cease and rendering the well safe at last. It will take at least a couple of months to get this done, bringing all available technology to bear. It will be an ecological disaster if the well flows all of the while; Optimistically, it could bridge off downhole.
It’s a sad day when something like this happens to any rig, but even more so when it happens to something on the cutting edge of our capabilities. The photos that follow show the progression of events over the 36 hours from catching fire to sinking.
The rig belongs to Transocean, the world’s biggest offshore drilling contractor. The rig was originally contracted through the year 2013 to BP and was working on BP’s Macondo exploration well when the fire broke out. The rig costs about $500,000 per day to contract. The full drilling spread, with helicopters and support vessels and other services, will cost closer to $1,000,000 per day to operate in the course of drilling for oil and gas. The rig cost about $350,000,000 to build in 2001 and would cost at least double that to replace today.
The rig represents the cutting edge of drilling technology. It is a floating rig, capable of working in up to 10,000 ft water depth. The rig is not moored; It does not use anchors because it would be too costly and too heavy to suspend this mooring load from the floating structure. Rather, a triply-redundant computer system uses satellite positioning to control powerful thrusters that keep the rig on station within a few feet of its intended location, at all times. This is called Dynamic Positioning.
The rig had apparently just finished cementing steel casing in place at depths exceeding 18,000 ft. The next operation was to suspend the well so that the rig could move to its next drilling location, the idea being that a rig would return to this well later in order to complete the work necessary to bring the well into production.
It is thought that somehow formation fluids – oil /gas – got into the wellbore and were undetected until it was too late to take action. With a floating drilling rig setup, because it moves with the waves, currents, and winds, all of the main pressure control equipment sits on the seabed – the uppermost unmoving point in the well. This pressure control equipment – the Blowout Preventers, or ‘BOP’s” as they’re called, are controlled with redundant systems from the rig. In the event of a serious emergency, there are multiple Panic Buttons to hit, and even fail-safe Deadman systems that should be automatically engaged when something of this proportion breaks out. None of them were aparently activated, suggesting that the blowout was especially swift to escalate at the surface. The flames were visible up to about 35 miles away. Not the glow – the flames. They were 200 – 300 ft high.
All of this will be investigated and it will be some months before all of the particulars are known. For now, it is enough to say that this marvel of modern technology, which had been operating with an excellent safety record, has burned up and sunk taking souls with it. The well still is apparently flowing oil, which is appearing at the surface as a slick. They have been working with remotely operated vehicles, or ROV’s which are essentially tethered miniature submarines with manipulator arms and other equipment that can perform work underwater while the operator sits on a vessel. These are what were used to explore the Titanic, among other things. Every floating rig has one on board and they are in constant use. In this case, they are deploying ROV’s from dedicated service vessels. They have been trying to close the well in using a specialized port on the BOP’s and a pumping arrangement on their ROV’s. They have been unsuccessful so far. Specialized pollution control vessels have been scrambled to start working the spill, skimming the oil up.
In the coming weeks they will move in at least one other rig to drill a fresh well that will intersect the blowing one at its pay zone. They will use technology that is capable of drilling from a floating rig, over 3 miles deep to an exact specific point in the earth – with a target radius of just a few feet plus or minus. Once they intersect their target, a heavy fluid will be pumped that exceeds the formation’s pressure, thus causing the flow to cease and rendering the well safe at last. It will take at least a couple of months to get this done, bringing all available technology to bear. It will be an ecological disaster if the well flows all of the while; Optimistically, it could bridge off downhole.
It’s a sad day when something like this happens to any rig, but even more so when it happens to something on the cutting edge of our capabilities. The photos that follow show the progression of events over the 36 hours from catching fire to sinking.
Sschell
Dude?
wholy crap!
Road Guy
Well-known member
$350 Million? Did I read that right??
damn I didnt know the gulf got that deep (me=dumb) but it was in almost a mile deep water?
I dont know how they would even fix something like that, hope their are smarter folks out there than me, but if bringing in another rig is the only proposed solution I cant see that happening too soon..
Its a shame what its going to do to the region down there, they have been hit hard enough one would think already...
damn I didnt know the gulf got that deep (me=dumb) but it was in almost a mile deep water?
I dont know how they would even fix something like that, hope their are smarter folks out there than me, but if bringing in another rig is the only proposed solution I cant see that happening too soon..
Its a shame what its going to do to the region down there, they have been hit hard enough one would think already...
RIP - VTEnviro
His Memory Eternal
We're too busy worrying about getting everyone drinking water in Eastern Mass to worry about other people's hiccups!
I saw that on either the Globe or the Herald (Boston papers) website today that gas spiked 6 cents/gal locally since the spill.
RIP - VTEnviro
His Memory Eternal
^Someone's 5/8" domestic service was a little leaky at the corp stop. No biggie.
D
Dexman PE
wilheldp_PE
PE, LEED AP, SPAM KING
Why would one oil rig, that wasn't even in full production yet, sinking cause gas prices to spike? Oh yeah...that's because gas prices are controlled by professional gamblers that don't understand a damn thing about the commodities that they trade.
What a freaking disaster. It sounds like everything that could go wrong, did.
I worked on offshore oil platforms back in the early 90s, and I always felt relatively secure that something like that wouldn't happen. Well, at the very least, that only I and those around me would burn and die in a quickly controlled blowout that would be shut down using the multiply redundant BOPs and other systems, and that the oil slick would stop within minutes.
I wonder if Freon has any insight, or if maybe he's even out there right now.
I worked on offshore oil platforms back in the early 90s, and I always felt relatively secure that something like that wouldn't happen. Well, at the very least, that only I and those around me would burn and die in a quickly controlled blowout that would be shut down using the multiply redundant BOPs and other systems, and that the oil slick would stop within minutes.
I wonder if Freon has any insight, or if maybe he's even out there right now.
Master slacker
Something awesome.
I have the rest of the photos from that report on my work computer. They're all simply fantastically horrible. I don't know how else to say it. Our fishermen, crabbers, and shrimpers are already tremendously hurt. Even if they could go out for healthy product, they're not allowed to get to their grounds in the first place. BP's going to pay, like bho stated, but they're not going to sweat too long. They'll pass the bill on to us so we can pay off their debt.
EM_PS
shining like a lighter...
PE-ness
Advanced Member
I keep thinking back to the words of Homer Simpson, upon learning of the Exxon Valdez spill. "Don't cry, Lisa, there's plenty more oil where that came from!"
BP did a fine job of covering it up. Forcing workers to sign no-fault papers before allowing them back on shore. Closing off the shores along the blast from the media.
Chucktown PE
Well-known member
I'm not sure I'd call that a cover up. And it wasn't BP's rig out there, it was Transocean's. My understanding is that it was Transocean's crew as well.
