Laser based system for bitumen content determination, E.G., using discrete wavelength spectroscopic analysis

• US 9,880,095 B2
• Filed: 11/29/2012
• Issued: 01/30/2018
• Est. Priority Date: 11/29/2011
• Status: Active Grant

• Current Assignee: Cidra Corporate Services, Inc.
• Original Assignee: Cidra Corporate Services, Inc.
• Inventors: Davis, Michael A., Fernald, Mark R.
• Primary Examiner(s): Sung, Christine
• Application Number:
  US14/360,813
• Publication Number:
  US 20140326885A1
• Time in Patent Office: 1,888 Days
• CPC Class Codes: G01N 21/3563 for analysing solids; Preparation of samples therefor
• CPC Class Codes: G01N 21/39 using tunable lasers
• CPC Class Codes: G01N 21/84 Systems specially adapted for particular applications
• CPC Class Codes: G01N 2201/0691 Modulated (not pulsed supply)
• CPC Class Codes: G01N 2201/0697 Pulsed lasers
• CPC Class Codes: G01N 2201/12 Circuits of general importance; Signal processing
• CPC Class Codes: G01N 33/24 Earth materials G01N33/42 takes precedence
• CPC Class Codes: G01N 33/241 for hydrocarbon content drilling mud G01N33/2823; drilling per se E21B; prospecting G01V

Abstract

The present invention provides a technique that uses discrete wavelengths of illumination of an ore sample, and through the use of optical filters and laser illumination the signal-to-noise ratio of the measurement can be greatly improved, and may take the form of apparatus featuring a signal processor configured to: receive signaling containing information about a spectral reflectance caused by discrete wavelengths illuminating an ore sample; and determine information about a bitumen content of the ore sample based at least partly on the signaling. The signal processor may provide corresponding signaling containing information about the bitumen content of the ore sample, including for further processing, printing or displaying.

Claims

1. A laser-based system for bitumen content determination of an ore sample, comprising:

a laser combination having discrete lasers configured to illuminate the ore sample with discrete laser wavelengths of light specifically targeting and corresponding to a reflectance band and an adjacent absorption band of bitumen;

a detector combination having narrow band optical filters and detectors centered at the discrete laser wavelengths of light and configured to

detect spectral reflectances reflected off the ore sample corresponding to the reflectance band and the adjacent absorption band of bitumen, and

provide signaling containing information about the spectral reflectances detected; and

a signal processor configured to

receive the signaling; and

determine corresponding signaling containing information about a bitumen content of the ore sample by comparing the spectral reflectances detected and associated with the reflectance band and the adjacent absorption band using a 2-band spectroscopic analysis of specifically targeted discrete laser wavelengths of light in combination with narrow band filtering of unwanted light, based at least partly on the signaling received.

2. A laser-based system according to claim 1, wherein the signal processor is configured to provide the corresponding signaling containing information about the bitumen content of the ore sample, including for further processing, printing or displaying.

3. A laser-based system according to claim 1, wherein the signal processor is configured to determine information about the bitumen content of the ore sample based at least partly on dips in the spectral reflectance in the discrete laser wavelengths illuminating the ore sample corresponding to the reflectance band.

4. A laser-based system according to claim 1, wherein each discrete laser is configured to focus a respective discrete laser wavelength to illuminate the ore sample.

5. A laser-based system according to claim 1, wherein the laser combination comprises two discrete lasers, and the detector combination comprises two narrow band optical filters and detectors.

6. A laser-based system according to claim 5, wherein the two discrete lasers are paired with matching narrow band optical filters and detectors to achieve an improved signal-to-noise.

7. A laser-based system according to claim 5, wherein the two discrete lasers are configured to be alternatively pulsed and encoded so as to improve discrimination.

8. A laser-based system according to claim 7, wherein the two discrete lasers are configured to receive a frequency modulation signal so as to spread a respective laser spectral width provided from the two discrete lasers.

9. A laser-based system according to claim 5, wherein the two discrete lasers are configured to be scanned over an area of interest, so that by scanning laser beams, an increased signal-to-noise ratio of the signaling detected can be maintained and still a large area can be scanned.

10. A laser-based system according to claim 1, wherein the discrete wavelengths include at least one discrete wavelength in a 1750 nm or 2330 nm region, which corresponds to absorption bands of bitumen.

11. A laser-based system according to claim 1, wherein the signal processor is configured to implement a 2-band analysis algorithm, including comparing a bitumen reflectance band to an adjacent absorption band for naturally occurring clays in the ore sample.

12. A laser-based system according to claim 11, wherein the bitumen reflectance band is about 2330 nm and the adjacent absorption band is about 2220 nm.

13. A laser-based system according to claim 1, wherein the signal processor is configured to use directly the signaling detected to calculate or determine the bitumen content of the ore sample.

14. A laser-based system according to claim 1, wherein the laser combination comprises tunable lasers configured to provide the discrete laser wavelengths illuminating the ore sample.

15. A laser-based system according to claim 1, wherein the detector combination comprises tunable optical filters and detectors configured to tunably filter the spectral reflectances.

16. A laser-based system according to claim 1, wherein

the laser combination is configured to receive a modulation signal and provide a modulated laser beam in the form of a discrete modulated laser wavelength;

and

the laser-based system comprises a lock-in amplifier used to extract the modulated laser beam provided from the laser combination.

17. A laser-based system according to claim 1, wherein the laser-based system comprises optics configured to enlarge respective spot diameters of laser beams in order to illuminate a larger ore body.

18. A laser-based system according to claim 1, wherein the signal processor may be configured to determine the information about the bitumen content of the ore sample based at least partly on spectroscopic analysis or processing of the signaling.

19. A laser-based system according to claim 1, wherein the detector combination comprises:

a first detector and filter combination configured to detect a first spectral reflectance caused by a first discrete wavelength provided by a first laser illuminating the ore sample corresponding to the reflectance band of bitumen; and

a second detector and filter combination configured to detect a second spectral reflectance caused by a second discrete wavelength provided by a second respective laser illuminating the ore sample corresponding to the adjacent absorption band of bitumen.

20. A method for determining a bitumen content of an ore sample using a laser-based system, comprising:

illuminating with a laser combination having discrete lasers the ore sample with discrete laser wavelengths of light specifically targeting and corresponding to a reflectance band and an adjacent absorption band of bitumen;

detecting with a detector combination having narrow band optical filters and detectors centered at the discrete laser wavelengths of light spectral reflectances reflected off the ore sample corresponding to the reflectance band and the adjacent absorption band of bitumen;

providing from the detector combination signaling containing information about the spectral reflectances detected; and

receiving in a signal processor the signaling; and

determining in the signal processor corresponding signaling containing information about a bitumen content of the ore sample by comparing the spectral reflectances associated with the reflectance band and the adjacent absorption band using a 2-band spectroscopic analysis of specifically targeted discrete laser wavelengths of light in combination with narrow band filtering of unwanted light, based at least partly on the signaling received.

21. A method according to claim 20, wherein the method further comprises providing from the signal processor the corresponding signaling containing information about the bitumen content of the ore sample, including for further processing, printing or displaying.

22. A method according to claim 20, wherein the method further comprises determining information about the bitumen content of the ore sample based at least partly on dips in the spectral reflectances in the discrete laser wavelengths illuminating the ore sample.

23. A laser-based system for bitumen content determination of an ore sample comprising:

two discrete lasers configured to illuminate the ore sample with discrete laser wavelengths of light specifically targeting and corresponding to a reflectance band and an adjacent absorption band of bitumen;

two narrow band filters and detectors centered at the disclosed laser wavelengths of light configured to

detect spectral reflectances reflected off the ore sample corresponding to the reflectance band and the adjacent absorption band of bitumen, and

provide signaling containing information about the spectral reflectances detected; and

a signal processor configured to

receive the signaling; and

determine corresponding signaling containing information about a bitumen content of the ore sample by comparing spectral reflectances associated with the reflectance band and the adjacent absorption band using an n-band spectroscopic analysis of specifically targeted discrete laser wavelengths of light in combination with narrow band filtering of unwanted light, where n is at least 2, based at least partly on the signaling received.

24. A laser-based system according to claim 23, wherein n equals 2 or 5.