Downhole x-ray source fluid identification system and method

Patent metadata

Field	Value
Publication number	US-9284836-B2
Application number	US-201313969607-A
Country	US
Kind code	B2
Filing date	Aug 18, 2013
Priority date	Nov 13, 2007
Publication date	Mar 15, 2016
Grant date	Mar 15, 2016

Abstract

A method and system for determining a property of a sample of fluid in a borehole. A fluid sample is collected in a downhole tool. While collecting, X-rays are transmitted proximate the fluid from an X-ray source in the tool and an X-ray flux that is a function of a property of the fluid is detected. The detected X-ray flux data is processed to determine the property of the fluid.

First claim

What is claimed is:

1. A method of determining a property of a sample of fluid, comprising:
while in a borehole, collecting a sample of fluid in a downhole tool;
while collecting the sample, transmitting X-rays proximate to the fluid from an X-ray source located in the tool and along a transmission path;
detecting a characteristic X-ray and a Compton scattered X-ray at an angle from the transmission path using a detector offset from the transmission path;
comparing an energy of the characteristic X-ray with an energy of the Compton scattered X-ray; and
determining the fluid property using the comparison.

2. The method of claim 1 wherein at least a portion of the fluid sample includes formation fluid.

3. The method of claim 1 further comprising identifying a relative intensity between the characteristic X-ray and the Compton scattered X-ray.

4. The method of claim 3 further comprising enhancing the relative intensity by increasing the angle.

5. The method of claim 1 wherein determining the fluid property includes determining the purity of the fluid.

6. The method of claim 1 wherein determining the fluid property includes determining a constituent of the fluid.

7. The method of claim 6 wherein the constituent of the fluid is a heavy metal.

8. The method of claim 1 further comprising:
determining an energy difference between the characteristic X-ray and the Compton scattered X-ray at the angle; and
increasing the energy difference by increasing the angle.

9. The method of claim 1 wherein comparing the energies includes a spectral response.

10. The method of claim 9 further comprising identifying a spectral distinction between the characteristic X-ray and the Compton scattered X-ray.

11. The method of claim 10 further comprising discriminating photons associated with the characteristic X-ray from photons associated with the Compton scattered X-ray.

12. A method of determining a property of a sample of fluid, comprising:
while in a borehole, collecting a sample of fluid in a downhole tool;
while collecting the sample, transmitting X-rays proximate to the fluid from an X-ray source located in the tool and along a transmission path;
detecting a characteristic X-ray and a Compton scattered X-ray at an angle from the transmission path using a detector offset from the transmission path;
comparing a spectral response of the characteristic X-ray with a spectral response of the Compton scattered X-ray; and
determining the fluid property using the comparison.

13. The method of claim 12 further comprising:
obtaining a Compton wavelength shift; and
using the Compton wavelength shift to determine the fluid property.

14. The method of claim 12 further comprising comparing the spectral responses to determine a constituent heavy metal in the fluid.

15. A system used in the method of claim 1 , and further including:
a formation tester conveyable downhole into the borehole, the formation tester including:
a probe engageable with a formation to form a seal and such that fluid communication between the formation and the interior of the formation tester is established;
a mechanism to control the collection of the fluid sample through the probe and into the formation tester;
a fluid testing device including the X-ray source and the offset detector, the X-ray source for transmitting the X-rays and the offset detector for detecting the characteristic X-ray and the Compton scattered X-ray; and
a control unit including a processor configured to compare the characteristic X-ray energy with the Compton scattered X-ray energy to determine the fluid property.

16. The system of claim 15 , wherein the offset detector includes an energy sensitive detector capable of differentiating the energy associated with the characteristic X-ray from the energy associated with the Compton scattered X-ray.

17. The system of claim 15 , wherein the processor is further configured to determine a constituent heavy metal of the fluid using the comparison.

18. The method of claim 15 , wherein the processor is further configured to determine the purity of the fluid by analyzing the energy associated with the characteristic X-ray compared to the energy associated with the Compton scattered X-ray.

19. A system used in the method of claim 12 , and further including:
a formation tester conveyable downhole into the borehole, the formation tester including:
a probe engageable with the formation to form a seal and such that fluid communication between the formation and the interior of the formation tester is established;
a mechanism to control the collection of the fluid sample through the probe and into the formation tester;
a fluid testing device including the X-ray source and the offset detector, the X-ray source for transmitting the X-rays and the offset detector for detecting the characteristic X-ray and the Compton scattered X-ray; and
a control unit including a processor configured to compare the characteristic X-ray spectral response with the Compton scattered X-ray spectral response to determine the fluid property.

20. The system of claim 19 , wherein the offset detector includes a spectra sensitive detector capable of differentiating the spectral response associated with the characteristic X-ray from the spectral response associated with the Compton scattered X-ray.

Assignees

• Halliburton Energy Services Inc

Inventors

• Rodney Paul F
• Spross Ronald L
• Truax Jerome Allen
• Gleitman Daniel David

Classifications

• E21B49/10

  using side-wall fluid samplers or testers · CPC title

• G01N2223/616

  earth materials · CPC title

• G01N2223/635

  fluids, granulates · CPC title

• G01N23/201

  by measuring small-angle scattering · CPC title

• E21B49/08 Primary

  Obtaining fluid samples or testing fluids, in boreholes or wells · CPC title