Carbon-based fluorescent tracers as oil reservoir nano-agents

Patent metadata

Field	Value
Publication number	US-9447682-B2
Application number	US-201514627688-A
Country	US
Kind code	B2
Filing date	Feb 20, 2015
Priority date	May 13, 2011
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

The present invention relates to carbon-based fluorescent nano-agent tracers for analysis of oil reservoirs. The carbon-based fluorescent nano-agents may be used in the analysis of the porosity of a formation. The nanoagents are suitable for injection into a petroleum reservoir and may be recovered from the reservoir for the determination of hydrocarbon flow rates and retention times.

First claim

That which is claimed is:

1. A method of analyzing a subsurface petroleum formation, comprising the steps of:
injecting a fluid comprising a plurality of fluorescent nanoagents produced from a solution comprising citric acid, an amino alcohol and deionized water reacted under conditions capable of synthesizing the fluorescent nanoagent into an injection well, said injection well being fluidly connected to the subsurface petroleum formation;
recovering the fluid injected into the injection well at a production well, said production well being fluidly connected to said subsurface petroleum formation;
analyzing the recovered fluid for the presence of the fluorescent nanoagents present therein.

2. The method of claim 1 , the method further comprising subsequent to the step of injecting the plurality of fluorescent nanoagents into the injection well, the step of injecting additional fluids into the injection well.

3. The method of claim 1 , wherein the additional fluids that are injected into the injection well include a high salinity brine.

4. The method of claim 1 , wherein the fluid comprising a plurality of fluorescent nanoagents is injected into the injection well at a rate of between about 2 and 4 barrels per minute.

5. The method of claim 1 , wherein the amino alcohol is selected from the group consisting of methanolamine, ethanolamine, and propanolamine.

6. The method of claim 1 , wherein the fluorescent nanoagent further comprises an organic functional group.

7. The method of claim 6 , wherein the organic functional group is present in an amount of between about 50% and 90% by weight.

8. The method of claim 1 , wherein the fluorescent nanoagent is stable at a temperature of about 100° C. to about 200° C.

9. The method of claim 1 , wherein the fluorescent nanoagent is stable at a salinity concentration of about 75,000 ppm to about 120,000 ppm.

10. The method of claim 1 , wherein the fluorescent nanoagent undergoes excitation at a wavelength in a range of between about 400 nm to 500 nm.

11. The method of claim 1 , wherein the fluorescent nanoagent exhibits emission at a wavelength in a range of between about 450 nm to 475 nm.

12. The method of claim 1 , wherein the fluorescent nanoagent is detected using luminescence spectroscopy.

Assignees

• Saudi Arabian Oil Co
• Univ Cornell

Inventors

• Kanj Mazen Y
• Rashid Mohammad Harunar
• Giannelis Emmanuel

Classifications

• Y10S977/773

  Nanoparticle, i.e. structure having three dimensions of 100 nm or less · CPC title

• E21B49/00

  Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells · CPC title

• Y10S977/896

  Chemical synthesis, e.g. chemical bonding or breaking · CPC title

• Y10T428/2982

  Particulate matter [e.g., sphere, flake, etc.] · CPC title

• C09K11/06 Primary

  containing organic luminescent materials · CPC title