Document Author: Merv Fingas

Review of the 2015 Alaska North Slope Oil Properties Relevant to Environmental Assessment and Prediction

Oil spill modeling and prediction are important facets of oil spill preparedness. The most important estimation and modeling algorithms are that for oil spill emulsification, evaporation, chemical dispersibility, and those that might be used to predict other countermeasures such as mechanical recovery and burning.

Oil spill modeling relies on algorithms that require a number of oil property inputs The 2015 sample of ANS oil was found to be similar to the North Slope oils analyzed in 2013 but different from those in the more distant past. It was much lighter and less viscous than those much older samples, but similar to the 2009 and 2013 samples. The environmental behavior parameters of evaporation, emulsification and dispersibility were predicted.

These show that they are similar and indicative of a medium oil. The new ANS is a medium oil that does not form emulsion, is dispersible and evaporates to an extent.

Analysis of Oil Biodegradation Products

Studies have shown that highly oxidized oil, including that undergoing biodegradation and photooxidation, is not properly analyzed by conventional techniques. Conventional analytical techniques may miss as much as 75% of the oil mass. Similarly for biodegradation analysis, conventional techniques may overstate biodegradation by as much as four times. Five possible analytical solutions to this problem are suggested and include; thin layer chromatography, derivitization and then GC analysis, FTIR, NMR and HPLC. The latter two techniques are typically applied to only the separated polar fractions of the oil. These techniques are in their infancy and much more work needs to be carried out. The biodegradation pathways of oil compounds are largely unknown. Biodegradation steps are known only for a few of the thousands of compounds in oils. Analytical methods for many of the biodegradation products are also absent or need development. The situation is very complex and only extensive research over dozens of years will improve the knowledge. The first step will be a generalized analysis step that includes most oxygenated compounds.

Skip to content