RAPID: Self Assembly of Chemical Dispersant Systems in the Treatment of Deep Water Hydrocarbon Releases

Tulane University, New Orleans LA

Investigators

Abstract

1043163 John The Macondo Oil Spill caused by the explosion of the Deepwater Horizon drilling rig operated by Transocean for British Petroleum, has the potential to rank amongst the most serious environmental catastrophes unless effective measures are taken to mitigate the consequences to the environment. Most importantly, it is necessary to disperse the oil over a wide range of the ocean water column and prevent the oil from reaching the shore where it can accumulate and create long term ecological hazards. The proposed research addresses the issues relating to creating oil droplets which can be effectively dispersed in the ocean water column. Requirements for dispersant efficacy include the following (1) The dispersant must be applied at the target oil at sufficient dosage to form droplets (2) It is important that the dispersant be applied early before the lighter components of the oil evaporate (3) The dispersant must be able to lower the oil-water interfacial tension sufficiently so that small oil droplets can be created which can be dispersed over the water column (4) It is preferable that the oil droplets remain dispersed long enough to be biodegraded by marine organisms. Alternatively, if the droplets are widely dispersed, it may be preferable to find a method to sediment the oil to the ocean floor where they can be biodegraded. The PIs propose to conduct research that will address the following aspects of dispersant design and efficacy evaluation (1) studies on the compositional variations of dispersants and their effects on droplet microstructure and stability (2) effects of compositional variations of oil characteristics to understand if droplet solidification can occur at the low temperatures and enhanced pressures relevant to deepwater injection of dispersants (3) introduction of methane into the system at high pressures and low temperatures to define the existence of gas hydrates in emulsion droplets (4) the implementation of highly biodegradable surfactants and biosurfactants to reduce toxicity potential significantly (5) the implementation of particle stabilized emulsions to gradually sediment the hydrocarbons and subject them to biodegradation. The impact of this research would be broad, as several large constituencies are being affected by this deepwater oil spill. They include livelihoods for the fishermen in the Gulf area, the ecological impact on the wetlands which may cause unsustainable inland erosion around the Louisiana coastline and a threat to wildlife that may undermine the prevailing ecosystem. And, indeed the future of oil drilling at these extreme undersea environments may be at stake. The PIs plan to disseminate the results of our research through on line postings as quickly as we can confirm their scientific validity, so that the broader scientific community can take advantage of them rapidly. Over the longer term (but clearly of less consequence at this moment of crisis), this research, which has a strong scientific underpinning but is focused on rapidly solving a critical national problem represents an ideal learning experience for graduate students. They plan to present the results of this work, as well as the broader problem and potential solutions to the local community through evening lectures, to students in our colloidal phenomena classes, and to high school students and teachers so that they are well-educated on the different aspects of oil spills. Both Tulane and URI have strong, streamlined programs at the universities for pursuing these avenues.