Media and Intelligentsia Panic, Problem Solvers Get to Work
BP has initiated the process of drilling a relief well, to allow access for stopping the flow of pressurised hydrocarbons through the original well. One oil expert expects the oil flow to taper off on its own, without need for a relief well. The relief well could take from 6 weeks up to 3 months to complete.
In the meantime, BP is planning to create a containment vessel of some type to fit around the oil spill at the seafloor. This would limit the ultimate size of the oil slick at the surface. Captured hydrocarbons would then be pumped for storage.
Floating oil booms on the surface will allow for retrieval of some floating oil perhaps via Dracone barge, and a controlled burn of trapped oil that cannot be retrieved. Concurrently, large quantities of chemical dispersant and biological degradation agents will be applied to the spill from the air and sea. The current oil spill is light crude, a large portion of which tends to evaporate into the air.
The US Coast Guard, the US Navy, and the Louisiana National Guard will all be involved in slick control efforts and environmental remediation, as well as other agencies of the US government.
The above image illustrates some of the natural processes that occur after an oil seep or spill.
Natural dispersion: If there is no possibility of the oil polluting coastal regions or marine industries, the best method is to leave it to disperse by natural means. A combination of wind, sun, current and wave action will rapidly disperse and evaporate most oils. Light oils will disperse more quickly than heavy oils.
Booms and skimmers: Spilt oil floats on water and initially forms a slick that is a few millimetres thick. There are various types of booms which can be used either to surround and isolate a slick, or to block the passage of a slick to vulnerable areas such as the intake of a desalination plant or fish farm pens or other sensitive locations.
Boom types vary from inflatable neoprene tubes to solid, but buoyant material. Most rise up about a metre above the water line. Some are designed to sit flush on tidal flats while others are applicable to deeper water and have skirts which hang down about a metre below the waterline.
Skimmers float across the top of the slick contained within the boom and suck or scoop the oil into storage tanks on nearby vessels or on the shore.
However booms and skimmers are less effective when deployed in high winds and high seas.
Dispersants: These act by reducing the surface tension that stops oil and water from mixing. Small droplets of oil are then formed which helps promote rapid dilution of the oil by water movements. The formation of droplets also increases the oil surface area, thus increasing the exposure to natural evaporation and bacterial action.
Dispersants are most effective when used within an hour or two of the initial spill. However they are not appropriate for all oils and all locations. Successful dispersion of oil through the water column can affect marine organisms like deep water corals and seagrass. It can also cause oil to be temporarily accumulated by subtidal seafood.
...Most of the components of oil washed up along a shoreline;can be broken down by bacteria and other micro-organisms into harmless substances such as fatty acids and carbon dioxide. This action is called biodegradation. The natural process can be speeded up by the addition of fertilising nutrients like nitrogen and phosphorous which stimulate growth of the micro-organisms concerned. _OilSpills
Only a small fraction of all petroleum spilled into marine waters comes from oil drilling activity.
The Deep Horizon disaster should not be brushed off or minimised. And yet, the news media and the Obama administration appear to be milking the tragedy for every ounce of profit and power-grabbing opportunism imaginable. And just wait until the lawyers start to show up!
Accusations that BP was too slow to react
More favourable description of BP's early response
Command center website and latest news
List of recent news articles from Offshore Mag
Futuristic swarm suction robot designed to suck up oil spills
Wikipedia article on oil well blowout
The distinction between the problem-solvers and the swinish opportunists has never been clearer. The next level will not allow the complete avoidance of disasters and catastrophes. But next level humans will not sit around and whine over a disaster. They will devise and implement imaginative yet competent solutions. That is the type of focus we should aim for.
Labels: oil, Oil Spills, panic
posted by al fin at 10:36 am
6 Comments:
two things: If the well can blow out the rig with that much pressure, there is a LOT of dissolved gas in that oil. Not good. What do the ROV's need in order to activate the shutoffs? Do they need to connect power? Turn a crank? Is there an "auxiliary power" plug on the valve assembly?
As I understand it, the BOP in this case was a 40 foot, 450,000 pound 5 hydraulic ram device, which should have been able to handle the pressure if working properly and operated as directed.
The BOP would have to be hydraulically closed in this situation. None of the remote points for closing the valves were functional.
The possible disruption in the hydraulic mechanism or line could have occurred within the BOP itself. There could also be a mechanical obstruction of some type preventing closing of the valves.
Thanks, a cogent answer. It sounds like there is a bank of hydraulic accumulators to provide power to the rams when the umbilical is gone. Whether the lines are sealed when the umbilical is cut (I assume check valves are in place somewhere) or not is a question. Whether the accumulators can be recharged if necessary by ROV is another. Whether there is system pressure enough to operate the BOP, considering that the blowout was quite a bit above the 20Kpsi of ocean head pressure may be at issue (the pdf talks of an upper consideration of 25kpsi), as well as debris jamming the rams, or if the combination of items is too much to handle until pressure drops. It appears there is enough force under normal conditions to shear the pipe and close the well. If things are already dicey with the pressures, and the drill pipe just happened to be at a couple joint (or even the drilling bit jammed in it(harder to shear?). Lots of possible problems, few solutions, since monkeying around with the pipe risks making bigger holes at the kinks.
Nice second comment, NCF, thanks.
Apparently you have some familiarity with the technology.
I am not certain how conservative the manufacturer (Cameron) is when compiling pressure limits. Neither have I read much reliable info about actual pressures estimated in Deep Horizon incident.
Human error is always a possibility as well, since as you say there was not much room for error if the pressures were close to or exceeding tolerances. A wrong signal sent at the wrong time could easily screw the works. Presumably that did not happen, but no doubt survivours from the control room will be intensively debriefed.
I notice you direct anger toward critics, and not toward those responsible for the mess.
Does it not strike you as outrageous that BP seemingly never contemplated the loss of control from a deepsea well?
Or the fact that they lobbied against installing acoustic shut-off devices... those devices are probably looking pretty cheap about now.
Good engineering does not dismiss the improbable. Good engineering is planning for the improbable, and having in place systems designed to mitigate the effects.
What if BP ran a nuclear reactor?
All the technology might be reasonably impressive, but the management and deployment of that technology rightly deserves criticism. It's been amature hour by most engineering standards. It's right to be critical until they can demonstrate good engineering skills.
Knowing that things go wrong, and knowing that deepwater is a harsh and unpredictable environment DEMANDS that loss of control is fully addressed and planned for.
Yes, there is much to criticise. But let's get all the facts first.
A lot of contractors were involved. BP is responsible overall, of course, but let's find out exactly what happened.
The deep sea floor -- like outer space -- can be full of surprises. There is a lot yet to be learned. (Nuclear reactor technology is slightly farther along.)
Planning for loss of control does not mean control will not be lost -- only that you have plans for recovering control at some point.
What is happening now will be in textbooks of the future. And, unfortunately, in lawsuit transcripts.
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“During times of universal deceit, telling the truth becomes a revolutionary act” _George Orwell
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