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During the Deepwater event, however, the oil industry for the firsttime released dispersants directly into a deep-sea blowout. Indeed,of the 1.84 million gallons of dispersants used during the spill,42 percent 771,000 gallons was applied at the wellhead, 5,067feet below the surface. The idea was to reduce both the amount ofoil reaching the surface and the amount of dispersants that neededto be applied. Today, the effectiveness and safety of this deep-sea dispersantapplication remains unknown, at least in part because of thedifficulty of monitoring the size of the oil droplets within thesubsea plume. That s where the VIMS research comes in. To maximize biodegradation, dispersants are designed to produceoil droplets that are less than 100 microns across," says Projectleader Paul Panetta, a scientist with Applied Research Associates,Inc., and an adjunct professor at VIMS. "But there are currently notools available to monitor droplet size in deep subsea blowouts.Our goal is to develop acoustic techniques for that purpose, givingspill responders a means to gauge the effectiveness of thedispersants and how much they should use. Tools do exist to measure droplet size within dispersed oil slicksat and just below the sea surface including ultravioletfluorometers and LISSTs (for Laser In-Situ Scattering andTransmissometers). But these optical devices are poorly suited foruse within highly opaque plumes of oil. Acoustic instruments and techniques offer a promising alternative. There s a reason that many marine mammals use sound rather thansight for long-distance communications, says team member CarlFriedrichs, chair of Physcial Sciences and head of the CoastalHydrodynamics and Sediment Dynamics lab at VIMS. Light can t gonearly as far in water let alone turbid water as compared tosound waves. Friedrichs notes that acoustic instruments also tendto be less delicate than their optical counterparts, and are betterable to withstand biofouling and the high pressures of the deepsea. Panetta and Friedrichs conducted the first experiments for theproject in December 2011 at the Ohmsett Wave Tank in Leonardo,N.J., which serves as the National Oil Spill Response Research& Renewable Energy Test Facility for the U.S. Department of theInterior. This 2.6-million gallon concrete basin one of thelargest wave tanks in the world measures 666 feet long by 65 feetwide by 11 feet deep. It features an immense piston for generatingwaves up to 3 feet high, an oil distribution and recovery system,and a motorized bridge for deploying instruments. During their Ohmsett tests, Panetta and Friedrichs compared theperformance of optical and acoustic instruments borrowed from theirlabs at VIMS, transmitting, receiving, and interpreting sound wavesand light as they reflected against an aqueous slurry of 20 partsof oil to 1 part dispersant. In a second experiment at VIMS, the pair performed a similarexperiment but on a much smaller and simpler scale. This timethey compared the performance of their optical and acousticalinstruments in a small bucket, adding dispersants to the same crudeoil used at Ohmsett and creating turbulence with a drill-poweredpaint mixer. They recently conducted a third test in Norway, in a tank operatedby SINTEF, the largest independent research organization inScandinavia. This tower tank specifically created for studyingsubsurface releases of oil measures 21 feet tall by 9 feet wideand allows room for various instruments including video cameras, aLISST, and, in this case, the acoustic equipment supplied by theVIMS team. Preliminary results are promising In all three cases, the team s preliminary results qualitativelyconfirm the potential superiority of an acoustic approach tomonitoring oil dispersion. Our tests showed that acoustictechniques were effective at penetrating the plume, says Panetta, whereas the LISST would have been ineffective. Our initialmeasurements indicate the acoustic measurements can track thedroplet size for a subsurface release of oil. The next step, says Panetta, is to take these data and turn theminto a measurement method that would tell us exactly what thedroplet size is. That would be valuable to the people spraying thedispersants, and valuable to the people modeling the fate of theoil, because during the cleanup of an oil spill, the size of theoil droplets affects everything. Panetta and Friedrichs say their ultimate goal is to partner withthe private sector so that commercial sonar manufacturers can adaptthe new technology to their existing instruments for use by the oiland gas industry. That s the longer term technology plan, saysPanetta, but we obviously have to first figure out the sciencebehind it to make it work. We have to solve the physics problem tofigure out which signals to analyze and how to interpret them so wecan get a quantitative measure of the oil-droplet size. We are high quality suppliers, our products such as Inflatable Paintball Bunkers Manufacturer , Inflatable Lighting Decoration Manufacturer for oversee buyer. To know more, please visits Combo Jumpers Rentals.
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