Wednesday, May 5, 2010

Shut down the well first

http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2010/05/04/EDT71D9E06.DTL
Neno Duplan
It appears that almost the entire focus of the response to the BP oil rig spill in the Gulf of Mexico is on how to deal with the oil on the surface of the water. The focus needs to be on shutting down the well.

As in cancer treatment, early action, even if risky, brings quicker results than dealing with metastasis.

Because the oil is flowing freely from an oil field under pressure, rather than from a ship, the supply of oil is potentially endless and it won't stop flowing until the underwater well is capped. That is what BP must focus on while the army of federal agencies and their consultants deal with the surface consequences of this growing disaster.

BP should consider the following:

-- Apply a small blast at the wellhead. This could shut down the well. There is some risk here, but it is not enough to exclude this option. After the blast, BP would have at worst one leak to deal with rather than many along the fallen riser pipe that sits bent, broken and leaking on the ocean floor. In this approach, the workers would cut the pipe at the wellhead, introduce the explosive through a damaged blowout preventer and hope for the best. The risk is that the pressure of the oil rising from the well could be overwhelming, and the flow from the well may actually increase for a short time. If the blast does not work, there are the other options.

-- Mud suction at the ocean bottom is a little-known phenomenon that has sunk submarines. Submarine operators know that this sometimes prevents a submarine from lifting itself off the ocean bottom. Mediterranean fishermen have considered this phenomenon in designing anchors for their boats for more than 2,000 years. A technology that takes advantage of what is known as "the breakout phenomenon" could be applied on the top of and below the leaking oil pipe. Think of an inverted drinking goblet the size of a one-story building. If that structure were dropped to the bottom of the sea so that it sinks the pipe into the sediment, it would reduce or stop the leaking until a permanent solution is found. The vibration applied on the sides of the structure would pull it down into the sediment, and side friction and mud suction would offset the pressure of the oil leak and keep the structure down. The difference in this technology from the one currently considered is that there would be no need for pumping oil to the surface ships - a difficult endeavor.

-- Bury the pipe in fast-setting concrete, similar to what the Russians did with the Chernobyl reactor. It was not a permanent solution, but it did stop the leak at the time. This is probably the least expensive and quickest alternative.

Or, instead of fast-setting concrete, interlocking concrete blocks could be manufactured easily and lowered to clamp the pipe and stop the leak.

The number of options is admittedly reduced when operating in 5,000 feet of water, but they exist. Some say that robots have never been used in an operation of this magnitude nor at this depth. However, the wreck of the Titanic was found lying on the ocean floor at a depth of about 13,000 feet, and submersible robots were used to retrieve objects from it. The Hughes Glomar Explorer, which was used in the attempt to lift a Russian nuclear submarine that had sunk in very deep waters near Hawaii, could offer some lessons and technology.

Ironically, the ship is still around and used for oil exploration in Indonesia. One thing is certain: There will be plenty of information gleaned to develop strategies for the next time.

Neno Duplan is the president and CEO of Locus Technologies in Mountain View. He did his 1986 doctoral dissertation on technology that exploits the breakout phenomenon.

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