Initial Study Of Establishing A Fingerprint Information System For Oils From The Platforms In South Sea With Fluorescence Spectroscopic Analysis

The purpose of this paper is to explore ways to build a preliminary fingerprint information system of flat oils in South Ocean. Currently there are sixteen platforms being exploited in the South Ocean of China. Oil spill could happen during the exploiting process as well as the transportation process, and a fingerprint information system could provide technical support for a scientific identification of such leaked oils. Fluorescence Spectroscopic Analysis (FSA) renders several advantages such as high sensitivity, high availability, and little fluctuation when time changes. The last one is due to the fact that the main source of fingerprint information is polycyclic compound, which has very low volatility and water-solubility, and is very slow to effloresce. Considering these advantages, this project has chose FSA as the identifying spectrums for platform oils. Using room temperature FSA as the basis, augmented by synchronous excitation FSA, this approach provided rich information source, and increased the reliability of oil source identification.Firstly platform oil samples are processed with a series of scans including general fluorescence spectroscopy, synchronous excitation spectroscopy, derivative fluorescence spectroscopy, and 3D fluorescence spectroscopy. Then all reference spectrums are compressed and saved in a uniform format. During identification stage, unknown spectrums are compared to the reference spectrums in the system, similarity factors are calculated and finally the matching records are listing in the order of similarity. This approach studied in-depth characteristics of spectroscopy of oil samples; and provided scientific foundation of identifying ocean oil spills.The researches have done in this project as follows:(1) Select six platforms as research objects among sixteen platforms beingexploited in the South Ocean of China and collect dehydrated crude oil samples of these selected platforms.(2) Scan the samples put up into uniform concentration with those collected crude oil samples by Fluorescence photometer and select the best parameters and conditions for the experiment.(3) Under the selected experimental parameters and conditions, general fluorescence scan, synchronous fluorescence scan, derivative fluorescence analysis, and 3D fluorescence analysis, and thus gain a series of fluorescence spectrograms.(4) Carry on numeric analysis on all those fluorescence spectrograms of collected crude oil samples, and get numeric parameters of all fluorescence spectrograms.(5) All fluorescence spectrograms are compressed and saved in a uniform format.The result shows:(1) General fluorescence spectroscopy and synchronous excitation spectroscopy represent only partial characteristics of platform oils, and are weak in identifying oils from close sources. Since all oils under study are from south sea, general fluorescence spectroscopy and synchronous excitation spectroscopy provides insufficient information for identification purpose.(2) Derivative fluorescence spectroscopy, which based on general fluorescence spectroscopy, is good at separating overlapping spectrums, thus reduce the noises, and results in enhanced characteristics of subtle spectrum structures and differential ability. The spectrums of derivative fluorescence spectroscopy of oils under study are different in that the number of peaks are different, and the standard deviations of both peak-to-bottom ratios and peak-to-zero ratios are greater than 0.05, therefore provide good digital fingerprint characteristics for oil samples.(3) Generally the range of 3D fluorescence spectrums are not disturbed by biological decomposition and water washing, therefore provides more accurate representation of oil characteristics. The forms of 3D fluorescence spectrums of oilsamples are similar, with different levels of fluorescence intensity, and different intensity-ratio between characteristic peaks. Sample number 4 is apparently different from others, indicating different maturity, source, and aryl-hydrocarbon constituents from other five oils samples.