Assessment of chemical dispersant effectiveness in a wave tank under regular non-breaking and breaking wave conditions.
Current chemical dispersant effectiveness tests for product selection are commonly performed with bench-scale testing apparatus. However, for the assessment of oil dispersant effectiveness under real sea state conditions, test protocols are required to have hydrodynamic conditions closer to the natural environment, including transport and dilution effects. To achieve this goal, Fisheries and Oceans Canada and the US Environmental Protection Agency (EPA) designed and constructed a wave tank system to study chemical dispersant effectiveness under controlled mixing energy conditions (regular non-breaking, spilling breaking, and plunging breaking waves). Quantification of oil dispersant effectiveness was based on observed changes in dispersed oil concentrations and oil-droplet size distribution. The study results quantitatively demonstrated that total dispersed oil concentration and breakup kinetics of oil droplets in the water column were strongly dependent on the presence of chemical dispersants and the influence of breaking waves. These data on the effectiveness of dispersants as a function of sea state will have significant implications in the drafting of future operational guidelines for dispersant use at sea.
Li
Zhengkai
Z
Center for Offshore Oil and Gas Environmental Research, Bedford Institute of Oceanography, Fisheries and Oceans DFO Canada, PO Box 1006, Dartmouth, NS, Canada B2Y 4A2. liz@dfo-mpo.gc.ca
Lee
Kenneth
K
King
Thomas
T
Boufadel
Michel C
MC
Venosa
Albert D
AD
D000059:Accidents; D008055:Lipids / Q000737:chemistry*; D010578:Petroleum; D012623:Seawater; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D008055:Lipids; D010578:Petroleum; D014874:Water Pollutants, Chemical; C470995:corexit 9500