Tuesday, May 4, 2010

Engineering and the Deepwater Horizon

Oil supply is finite. The oil companies therefore work pretty hard on new ways to get it, new sources, and new efficiencies. Standards of safety and cleanliness rose with the ecological movement--and the rise of international banking and insurance risk pools. But geological terrain remains a huge challenge for the oil industry. So does human error.

The Deepwater Horizon was a new advance in offshore drilling, a "seventeenth generation" oilfield platform: large, built in 2001 so new, 396 feet x 256 feet wide, (100 feet wider than a football field), holding a 126-person crew. The drilling was done, and they were cementing the steel casing at the time of the blowout.

The final assessments on the DH catastrophe are in the future. But as the Christian Science Monitor said, the risk of blowout is always present in the oil industry. Geology is going to be a major factor.

According to the Schlumberger Oil Glossary, a blowout is:
An uncontrolled flow of reservoir fluids into the wellbore, and sometimes catastrophically to the surface. A blowout may consist of salt water, oil, gas or a mixture of these. Blowouts occur in all types of exploration and production operations, not just during drilling operations. 
In other words, an unforeseen extra volume flows up due to a drastic change in pressure or volume of fluids or gases. Some geologic turbulence occurred, and despite state-of-the art technology, everything went to hell. Seventeen workers were injured; eleven died. Five fireboats responded, both private and Coast Guard. Search and rescue by the Coast Guard by sea and land. The platform is gone.

How to Clean an Oil Spill
Here is a good general introduction: the four ways to clean an oil spill  Then I added one more large category.
a. Nothing. Truly, that sometimes is the best thing. Just as you would not scrub your face with a floor brush, a cleaning effort can do as much or more damage as leaving Nature to sort it out. (Not right now, though.)

b. Booms and Skimmers. This is what we heard about first. A boom is like a long hot dog with a flange or draft. The flange keeps it upright in the water. The cylindrical part may or may not be absorbent of oil. They are rated for use according to the turbulence of the water. A swamp flange, for instance, will be different than the ones used in the Gulf.

For this disaster, we've also heard about spreading booms for containment and then burning the oil off. The no-win/no-win: air pollution or oceanic pollution? For various reasons, the air pollution seemed a better choice.
I would say, chief among these is the economic health of shore communities and the fate of wetlands. Like a. above, it is a dispersal method.

c. Dispersant Chemicals. That's kind of like help for a. natural breakdown of the compounds in wind, water, salt, and sun.

d. Biological Agents: bacteria that eat oil for dinner. Here is a picture, much magnified of course. This one sounds better than all the rest. Reason: because the oil does not have to go anywhere else. With other methods, even boom-and-skim, something has to happen to the oil collected afterward. Also it gives us a warm feeling to know that Earth can handle its own problems.  In truth, oil is geologically under pressure. That means it leaks naturally, too, and frequently from the ocean floor or through seeps on land. (That's why these bacteria exist in nature. It's not a reason to yawn over massive industrial oil spills though.)

Here is a 1992 article about MIT's study of bacteria that can eat oil, methane, and even PCBs, transforming them to carbon dioxide and water. The study was trying to figure out the biochemical mechanism so it can be duplicated chemically as well as understood biologically. Now you can buy those bacteria by the drum at janitorial supply firms.

e. Feats of Engineering.
This video gives a good basic explanation of the situation and the engineering problems, from al-Jazeera.

The best place to find out what's going on with the Oil Spill is at the British Petroleum site. This is one of their strengths--they always give excellent information. Right now, I am sure they are employing the first through fourth remedies (the first, nothing, by default), but the permanent remedy will be one of engineering: drilling a new shaft that diverts the oil before it gets to the break points in the old pipe. BP started working on the alternate well on Sunday, May 2. They expect this procedure to take three months. Usually off-shore well-drilling takes seven to ten years--this is not nearly as deep though. But it must be done right/safely, so anything faster is not realistic.

Here is a map of the spill, updated daily at British Petroleum.

A Little More Overview
Bloomberg reports Business News--so before anyone gets riled--this story is partly about stock prices. It also reviews the problems that BP has had in the United States this past decade. The Alaska Pipeline spill could only have been human inattention. The final report on the refinery disaster in Texas City blamed most of it on bad management, i.e., outdated infrastructure and lax training. That will probably not be the finding in the report for the Deepwater Horizon.


Those problems began to surface under the latter part of the reign of CEO John Brown. Brown worked diligently to internalize UN standards of cleanliness and environmental safety to business as usual. His enthusiastic response to the British "Publish What You Pay" campaign added fiscal transparency to an industry that has a poor reputation in that regard. So much of BP's work has been very fine. You won't always hear that, and especially not now--not even from Bloomberg.


Risky Business
But regardless of BP's tarnished reputation or its gleaming internal values, a platform exploded. Seventeen people were injured. Eleven people were killed. Now the turtles are dying, the tourist and fishing industry will take a body hit, the oyster beds may be ruined. A massive effort by government agencies, private citizens, and firms has been employed.  BP will spend millions on it, and like all disasters, things will still not be the way they were before.

Pressurized parts of the earth do not answer to any safety or health regulation. The burden is on the oil companies to plan for these contingencies. Yet somehow like farmers who depend on weather and land knowledge--you can consult an almanac or a geological table, use an army of consultants, build new technologies, and get better equipment. You will still take a risk. This time we are all sharing it, someplace besides the gas pump.

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