System and method for contamination monitoring

Patent metadata

Field	Value
Publication number	US-12560084-B2
Application number	US-201917285925-A
Country	US
Kind code	B2
Filing date	Oct 17, 2019
Priority date	Oct 17, 2018
Publication date	Feb 24, 2026
Grant date	Feb 24, 2026

Abstract

A method includes receiving first fluid property data from a sample flowline of a focused sampling system and receiving second fluid property data from a guard flowline of the focused sampling system. The sample flowline and the guard flowline are each configured to sample formation fluid from a hydrocarbon reservoir, the formation fluid includes native formation fluid and a contaminant, and the first fluid property data includes an optical density of the native formation fluid and the second fluid property data includes an optical density of the contaminant

First claim

What is claimed is:

1 . A method comprising:
receiving, using a first sensor coupled to a sample flowline of a focused sampling system, first optical density data of a native formation fluid drawn into the sample flowline from a hydrocarbon reservoir via a first pump; receiving, using a second sensor coupled to a guard flowline of the focused sampling system, second optical density data of a contaminant fluid drawn into the guard flowline from the hydrocarbon reservoir via a second pump; combining the first optical density data and the second optical density data to generate combined optical density data; determining a derivative of the combined optical density data as a function of pumped volume of the native formation fluid through the sample flowline and the contaminant fluid through the guard flowline; performing a linear analysis based on the combined optical density data with respect to the derivative of the combined optical density data to determine an intercept, wherein the linear analysis includes a fitting of the combined optical density data with the derivative of the combined optical density data multiplied by pumped volume, and wherein the fitting includes a weighted least squares algorithm that assigns higher weights to most recent data points of the combined optical density data and the derivative of the combined optical density data multiplied by pumped volume; estimating a contamination profile of the native formation fluid based on the intercept and the combined optical density data; and adjusting, by an electronic controller based at least in part on the contamination profile, the first pump to adjust a native fluid flow rate of the native formation fluid through the sample flowline or the second pump to adjust a contaminant fluid flow rate of the contaminant fluid through the guard flowline.

2 . The method of claim 1 , wherein the first optical density data includes a plurality of first optical density data points measured at a plurality of wavelengths, and wherein the second optical density data includes a plurality of second optical density data points measured at the plurality of wavelengths.

3 . The method of claim 2 , wherein performing the linear analysis includes iteratively performing the linear analysis based on the combined optical density data and the derivative of the combined optical density data at each wavelength of the plurality of wavelengths to determine a plurality of intercepts.

4 . The method of claim 3 , wherein iteratively performing the linear analysis to determine the plurality of intercepts includes using a RANSAC algorithm.

5 . The method of claim 1 , wherein performing the linear analysis to determine the intercept includes using the Beer-Lambert law.

6 . The method of claim 1 , wherein performing the linear analysis to determine the intercept includes performing the linear analysis after a target amount has passed through one or both of the sample flowline and the guard flowline.

7 . The method of claim 1 , further comprising adjusting, by the electronic controller based at least in part on the contamination profile, a valve of the focused sampling system to cause a portion of the native formation fluid to enter a sample bottle from the sample flowline.

8 . The method of claim 1 , wherein the native formation fluid is pumped through the sample flowline in a flow direction by the first pump, and wherein the first pump is coupled to the sample flowline upstream of the first sensor in the flow direction.

9 . The method of claim 1 , wherein determining the derivative of the combined optical density data includes determining the derivative according to:

OD
=

C
-

1
α

⁢

d
⁢
O
⁢
D

d
⁢
v

⁢
v

where OD is the combined optical density data, v is the pumped volume, C is the intercept, and α is an exponent of power-law for evolving contamination.

10 . A focused sampling system, comprising:
a sample flowline; a first pump coupled with the sample flowline, the first pump configured to draw a native formation fluid into the sample flowline from a hydrocarbon reservoir; a guard flowline; a second pump coupled with the guard flowline, the second pump configured to draw a contaminant fluid into the guard flowline from the hydrocarbon reservoir; a first sensor coupled to the sample flowline and configured to generate first feedback indicative of a first optical density of the native formation fluid drawn into the sample flowline by the first pump; a second sensor coupled to the guard flowline and configured to generate second feedback indicative of a second optical density of the contaminant fluid drawn into the guard flowline by the second pump; and a controller communicatively coupled to the first sensor and the second sensor, the controller configured to:
receive the first feedback and the second feedback;
combine the first optical density of the native formation fluid and the second optical density of the contaminant fluid to generate combined optical density data;
determine a derivative of the combined optical density data as a function of pumped volume of the native formation fluid through the sample flowline and the contaminant fluid through the guard flowline;
perform linear analysis on the combined optical density data with respect to the derivative of the combined optical density data to determine an intercept, wherein the linear analysis includes a fitting of the combined optical density data with the derivative of the combined optical density data multiplied by pumped volume, and wherein the fitting includes a weighted least squares algorithm that assigns higher weights to most recent data points of the combined optical density data and the derivative of the combined optical density data multiplied by pumped volume;
estimate a contamination profile of the native formation fluid based on the intercept and the combined optical density data; and
adjust, based at least in part on the contamination profile, the first pump to adjust a native fluid flow rate of the native formation fluid through the sample flowline or the second pump to adjust a contaminant fluid flow rate of the contaminant fluid through the guard flowline.

11 . The focused sampling system of claim 10 , wherein the sample flowline and the guard flowline are fluidly coupled to a 3-dimensional radial probe configured to contact a sampling zone of the hydrocarbon reservoir.

12 . The focused sampling system of claim 10 , wherein the first sensor comprises a first optical spectrometer and the second sensor comprises a second optical spectrometer separate and distinct from the first optical spectrometer.

13 . The focused sampling system of claim 10 , further comprising:
a sample bottle and a valve, the sample bottle configured to collect the native formation fluid from the sample flowline via the valve, wherein the controller is further configured to adjust, based at least in part on the contamination profile, the valve to direct the native fo

Assignees

• Schlumberger Technology Corp

Inventors

• Hsu Kai
• Pfeiffer Thomas
• Wang Kang
• Schulz Dan
• Kristensen Morten
• Zuo Youxiang

Classifications

• G01N21/94

  Investigating contamination, e.g. dust (G01N21/85 takes precedence) · CPC title

• G01N21/8507

  Probe photometers, i.e. with optical measuring part dipped into fluid sample · CPC title

• G01N21/5907

  Densitometers · CPC title

• G01N21/31

  Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry {(G01N21/72 takes precedence)} · CPC title

• E21B49/10

  using side-wall fluid samplers or testers · CPC title