Study on weathering characteristic of aromatic hydrocarbons specific to unconditional oil based on concentration-resolved-fluorescence spectroscopy

With the rapid decline of conventional crude oil’s production and transportation, heavy crude oil, heavy oil, oil sands, oil shale and other unconventional oil have gradually become the main body of the marine oil spills. The used oil spill fingerprinting methods mainly for conventional oil are facing new challenges. According to the time-resolved fluorescence spectroscopy, concentration value is introduced as a new data dimension to the fluorescence spectra and the concentration-resolved-fluorescence spectroscopy (CRFS) is developed to express more PAHs information. Laboratory simulation experiments of weathering and distillation were carried out and the results demonstrate this method has strong anti-weathering and anti-interference ability. Oil source classification of close-related heavy crude oil samples under light weathering and seawater weathering lasting 120 d are studied. 96% of the correct rate for the closely related oil source samples is achieved by combining Gabor wavelet with supported vector machine (SVM). The obtained results suggest that the newly-developed method may become specifically applicable in spilled oils identification and also can be applied to other multi-fluorophoric systems such as in petroleum exploration, dissolved organic matter in environment monitoring and petroleum exploration.