The idea now is to pump a fluid that will block the flow. In the oil field this fluid is often a special mixture whose molecules lock together when it’s under pressure. Oil drillers call it “mud.” It looks like mud, but there’s more to it.
The molecular lock-together feature of a fluid is called “dilatancy.” The classic dilatant fluid in our everyday experience is cornstarch mixed with a small amount of water. It’s goopy, until you slap it or shake it. It locks up and does not splatter at all. So it is with drilling mud.
British Petroleum (BP) has been pumping drilling mud into the Preventer plumbing for almost two days. It seems to have slowed the oil flow a little, but not enough.
The engineers, or at least the spokesmen for the engineers, said they plan a “junk shot.” The idea is to add bits of hard material to the mud. Traditionally, in the Texas oil field, drillers add cut-up car tires and old driving range golf balls. This “bridging” material sometimes helps the dilatant mud molecules lock up. The pipe is so big, and the flow so fast, that a golf ball isn’t really that big an object. It could easily jam against an edge or pipe joint– and that would be good. Looking at the BP executive’s faces, it doesn’t seem like this is going to work either.
Next, I expect engineers along with the Remotely Operated submarine Vehicle (ROV) drivers will cut some large portion of the top preventer off. The next pipe up the drill string is called the “riser,” and I imagine that’s what they’ll go after next. It’s big job because the material is a hard type of stainless steel. And, it’s a long way around the big pipe with a fancy saw and buffing grinder, especially when you’re doing it with a claw-fingered robot to work the material and grainy video to guide you.
After that, I hope the managers let go of the idea of trying to capture any more oil until the relief, or drilled-in-from-the-side, well is cut. I hope they put a cap or slug made from a few thousand tons of concrete on top. They could let it ooze very slowly for a few weeks, until they can get to the well casing or liner by coming in from the side. Drilling these relief wells will take a few months, because it’s, once again, miles down and hundreds of meters of solid rock.
About the rate of oil flow: there have been a great many questions about how much oil is flowing per day. At first, looking at satellite data, people thought it was about 5,000 barrels a day. A barrel is 42 gallons. So, it’s a great many gallons. (A “drum” is 55 gallons– another confusing feature of the old English system of units.) Well, it turns out most of the oil isn’t making it to the surface of the sea. It’s floating somewhere in between the sea floor and surface– a goopy mess for any living thing in the ocean.
I have some small experience in oil fields, or in the “oil patch.” I worked for a shipyard that built the world’s premier oil slick skimming boat. We had a machine derived from skimming technology that performed the seemingly trivial task of separating oil and water.
You might think it would be easy, but in nature, dust particles or plankton organisms (plankters) get covered with oil in such a way that they neither sink nor float. They’re neutrally buoyant. As small globs of oily goo, they clog up all kinds of plumbing– including the gills, fins, and wings of fish and birds.
This fundamental experience helped me explain to news anchors and viewers why there was such discrepancy between the National Oceanic and Atmospheric Administrations satellite assessment of size of the spill compared with the measurement of the pipe gusher’s oil leak.
I hope BP takes this business very seriously. Any information they are not disclosing will come out one day when various employees or friends of employees reveal the true decision process. I remain concerned that the traditions of oil spills on land are too strongly influencing the procedures being developed on the bottom of the Gulf, an ecosystem people all over the world depend on.
We use a lot of energy. This disaster helps us recognize how complex or oil technology is, and how much can go wrong. Let’s learn from this, wean ourselves from oil, and change the world.
