Characterizing petroleum product contamination using fluorescence signal

Patent metadata

Field	Value
Publication number	US-10048205-B2
Application number	US-201715485803-A
Country	US
Kind code	B2
Filing date	Apr 12, 2017
Priority date	Apr 14, 2016
Publication date	Aug 14, 2018
Grant date	Aug 14, 2018

Abstract

Methods and systems for determining contamination in a petroleum-based sample, including irradiating the petroleum-based sample with a light beam from a light source such that a fluorescence signal is generated, guiding, by a mirror, the fluorescence signal to a gear-less rotating diffraction grating, the gear-less rotating diffraction grating spatially separating a fluorescence wavelength from the florescence signal, detecting, by an optical detector, fluorescence wavelength, transforming the fluorescence wavelength into a spectral contour diagram, the spectral contour diagram comprising a fluorescence wavelength variation over time, and determining, the contamination in the petroleum-based sample using the spectral contour diagram.

First claim

What is claimed is:

1. A method to determine contamination in a petroleum-based sample, the method comprising:
irradiating the petroleum-based sample with a light beam from a light source such that a fluorescence signal is generated;
guiding, by a mirror, the fluorescence signal to a gear-less rotating diffraction grating, the gear-less rotating diffraction grating spatially separating a fluorescence wavelength from the fluorescence signal;
detecting, by an optical detector, fluorescence wavelength;
transforming the fluorescence wavelength into a spectral contour diagram, the spectral contour diagram comprising a fluorescence wavelength variation over time; and
determining, the contamination in the petroleum-based sample using the spectral contour diagram.

2. The method of claim 1 , wherein the sample is a liquid that comprises fluorescent or phosphorescent molecules.

3. The method of claim 1 , wherein the sample comprises refined petroleum products or crude petroleum products.

4. The method of claim 1 , wherein the sample is irradiated with the light beam as the sample flows through a pipeline.

5. The method of claim 4 , further comprising forming an optical window that is transparent to the fluorescence signal and the light beam in the pipeline.

6. The method of claim 1 , wherein the optical detector is configured to detect a spectral range from about 350 nanometers to about 700 nanometers in real time.

7. The method of claim 1 , wherein detecting the fluorescence wavelengths is performed by a photon counting multi-scaler optoelectronic detector.

8. The method of claim 7 , further comprising determining an optical intensity of the fluorescence signal by correlating a frequency of photon incidences detected by the photon counting multi-scaler optoelectronic detector within pre-defined subsequent time intervals over several periods.

9. The method of claim 1 , further comprising mounting the gear-less rotating diffraction grating on a rotating axis of an encoded motor.

10. The method of claim 1 , further comprising selecting, by an integrated decoder, a wavelength of the gear-less rotating diffraction grating.

11. The method of claim 10 , wherein selecting the wavelength comprises rotating the gear-less rotating diffraction grating from a first position to a second position.

12. The method of claim 10 , wherein selecting the wavelength comprises generating a spectral range from about 350 nanometers to about 700 nanometers.

13. The method of claim 12 , wherein generating the spectral range is completed in about 2 seconds.

14. The method of claim 1 , wherein the light source comprises a light-emitting diode.

15. The method of claim 1 , wherein the light beam has an intensity in a pico-Joule range and is smaller than 1 nano-Joule.

16. The method of claim 1 , wherein the light beam is a pulsed light beam.

17. The method of claim 1 , further comprising generating calibration curves based on samples comprising pre-known percentages of contamination.

18. The method of claim 17 , wherein determining the contamination based on the spectral contour diagram comprises correlating the spectral contour diagram to the calibration curves.

19. The method of claim 18 , wherein correlating the spectral contour diagram to the calibration curves is performed for a particular set of optical parameters and a particular set of temporal parameters.

20. A system to diagnose an oil contamination, the system comprising:
a gear-less rotating diffraction grating configured to receive a fluorescence signal generated by irradiating a petroleum-based sample with a light beam, the gear-less rotating diffraction grating configured to spatially separate a fluorescence wavelength from the fluorescence signal;
an optical detector configured to detect a fluorescence wavelength separated from the fluorescence signal by the gear-less rotating diffraction grating; and
an optical signal processor configured to perform operations comprising:
transforming the fluorescence wavelength into a spectral contour diagram, the spectral contour diagram comprising a fluorescence wavelength variation over time, and
determining the oil contamination in the petroleum-based sample using the spectral contour diagram.

21. The system of claim 20 , wherein the sample comprises refined petroleum products or crude petroleum products, and wherein the sample is a liquid that comprises fluorescent or phosphorescent molecules.

22. The system of claim 20 , wherein the sample is irradiated with the light beam as the sample flows through a pipeline.

Assignees

• Saudi Arabian Oil Co

Inventors

• Hegazi Ezzat
• Cunningham Vincent
• Brunner Christof
• Stamm Christoph

Classifications

• G01N21/645 Primary

  Specially adapted constructive features of fluorimeters · CPC title

• G01N33/28

  Oils {, i.e. hydrocarbon liquids} (edible oils or edible fats G01N33/03) · CPC title

• G01N21/85

  Investigating moving fluids or granular solids · CPC title

• G01N2201/0621

  Supply · CPC title

• G01N2021/6463

  Optics · CPC title