Downhole Fluid Sampling Tool Contamination Analysis

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Accurate determination of fluid properties from downhole fluid samples is hindered by contamination with drilling fluids, leading to non-representative measurements and inefficiencies in pump-out processes, which can result in lost rig time and increased risks of stuck tools.

Innovation Solution

A downhole fluid sampling tool equipped with a fluid analysis module that uses a distribution function in conjunction with an equation of state to determine fluid contamination and component concentrations, allowing for real-time characterization of reservoir fluids even when contaminated, by measuring properties such as C1, C2, C3, C4, C5 weight percent, gas-oil ratio, oil density, and bubble point.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional pump-out techniques are used to reduce drilling fluid contamination, then fluid sample purity is improved, but rig time is lost and risk of stuck tools increases

Engineering Contradiction:

Improvefluid sample purityVSAvoidrig time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The patent replaces mechanical pump-out techniques with a downhole fluid analyzer that uses spectroscopic or chromatographic methods to detect and quantify drilling fluid contamination in real-time. This substitution eliminates the need for prolonged pump-out operations while providing accurate contamination assessment, thereby reducing rig time loss and stuck tool risks.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces a downhole fluid analyzer as an intermediary device between the contaminated fluid sample and the decision-making process. This analyzer provides real-time contamination data, enabling operators to make informed decisions about when to proceed with sampling without requiring extensive pump-out time, thus balancing purity requirements with time efficiency.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Measurement precision

If pump-out time is extended to reduce drilling fluid contamination, then fluid sample purity is improved, but risk of stuck tools increases

Engineering Contradiction:

Improvefluid sample purityVSAvoidtool stability

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The patent replaces the mechanical pump-out process with a downhole fluid analyzer that spectrally or chromatographically characterizes the fluid sample in situ. This eliminates the need for extended pump-out operations that expose tools to stuck risks, while still achieving accurate contamination assessment through real-time analysis.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent performs fluid contamination analysis downhole before the tool is retrieved to surface. By determining contamination levels in situ, operators can make go/no-go decisions about sampling operations before committing to extended pump-out sequences, thereby avoiding situations that could lead to stuck tools.

Inventive Principle:

Principle #10Preliminary action

3Productivity

If downhole analysis is performed to provide real-time fluid properties, then productivity is improved, but measurement accuracy may be compromised by contamination

Engineering Contradiction:

Improvereal-time analysis capabilityVSAvoidfluid property accuracy

Core Design Contradiction:

ProductivityVSMeasurement precision

Solution Approach 1:

The patent converts the harmful effect of drilling fluid contamination into a beneficial diagnostic opportunity. By using the downhole fluid analyzer to detect and quantify contamination signatures, the system not only identifies the presence of contaminants but also compensates for their effects, enabling accurate determination of true reservoir fluid properties even in contaminated samples.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent implements a feedback mechanism where the downhole fluid analyzer continuously monitors fluid composition and provides real-time data on contamination levels. This feedback enables operators to adjust sampling parameters or interpret results with appropriate contamination corrections, maintaining measurement accuracy while achieving real-time productivity benefits.

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS11156083B2Drilling fluid contamination determination for downhole fluid sampling tool

Publication Date: 2021.10.26 HALLIBURTON ENERGY SERVICES INC

AI summary

Disclosed are methods and systems for determination of fluid contamination of a fluid sample from a downhole fluid sampling tool. A method may comprise obtaining a fluid sample, wherein the fluid sample comprises a reservoir fluid contaminated with a well fluid; obtaining input parameters, wherein the input parameters comprise fluid properties obtained from measurement of the fluid sample and mud filtrate composition; obtaining initial values of iterative parameters, wherein the iterative parameters comprise fluid contamination of the fluid sample; determining calculated fluid properties of the reservoir fluid using equation of state flash calculating; and repeating steps of determining component mole fractions and determining calculated fluid properties for use in the mole fraction distribution function until a comparison of one or more of the calculated fluid properties with one or more of the input parameters is within a tolerance error.