Reservoir Fluid Analysis - Weatherford Laboratories

higher standards
Reservoir Fluid Analysis
a proven road map
Weatherford Laboratories’ full-service fluid analysis combines the industry’s latest state-of-the-art laboratory
characterization tools with sophisticated numerical characterization in the form of equation of state (EOS) modeling.
Our staff of highly qualified analytical experts works with each client to custom-design a fluid analysis protocol that meets
the specific development planning and production optimization goals of a particular asset. While the details of each
analysis protocol are specific to a particular field, each follows the same general road map to reservoir understanding and
are designed to:
In-depth Fluid Analysis for the Life of the Field
From discovery to abandonment, reservoir fluid characterization plays a critical role in optimizing each stage of a well’s life
cycle. While accurate fluid characterization guides the design and optimization of down hole production strategies and the
operation of surface facilities, inaccurate analysis creates a high degree of uncertainty regarding in-place-volume estimates
and recovery predictions. As a result, the asset’s true value and the operator’s profit potential may go unrealized.
Weatherford Laboratories’ comprehensive reservoir fluid analysis techniques establish the physical and chemical properties
of field fluids that help form the foundation for efficient field development planning. Understanding critical features such
as hydrocarbon type, fluid volumes, flow characteristics, and the pressure-volume-temperature (PVT) behavior of the
reserves in place is crucial for:
• Estimating the recovery potential of reserves
• Understanding what type of hydrocarbons will be produced
• Identifying the presence of any undesirable compounds in the crude that may inhibit
production or impact the asset’s infrastructure
• Determining allocations of production components
• Accurately planning and sizing production and processing facilities
• Obtain representative fluid samples at surface and,
if applicable, bottom hole
• Ensure reliable recombination parameters, such as representative gas/oil hydrocarbon ratio (GOR) or gas/
liquid ratio (GLR), and/or target saturation pressures
(bubble point or dew point) at reservoir pressure and temperature are met
• Ensure accurate pressure-volume-temperature (PVT)
measurements at both reservoir and separator conditions
• Implement QA/QC procedures to ensure data quality
• Develop mathematical models to capture fluid properties as
a function of pressure, temperature and composition
Time and again, this road map has proven itself as a robust and
comprehensive path to understanding the character of the produced hydrocarbons over time and to the development of a
field operations plan to optimize production.
sampling expertise
Efficient sampling methods for all stages of a well’s life.
Any successful reservoir fluid analysis campaign hinges on the ability to collect
Weatherford Laboratories always ensures that wells are properly conditioned prior to sampling. Following the well
sufficient volumes of high-quality, representative fluid samples. In addition to
conditioning, but prior to sampling, a measurement of bottom hole pressure and temperature should be made in
samples for PVT analysis, adequate volumes must be collected for plant and
order to correlate laboratory data with reservoir data.
process analyses, geochemical analysis for fluid-source identification and crude
assay for refinery processes. Weatherford Laboratories’ sampling protocols focus
Sample Transfers
on obtaining clean and representative fluid samples from both down hole and
Whether in the field or in the laboratory, down hole samples from either formation test tools or other wireline samplers
surface. The field operation’s layout and the operator’s analysis goals are carefully
are fully restored and stabilized at reservoir conditions prior to sub-sampling or transfer into a piston sample cylinder
reviewed to select the appropriate sampling method and tools, as well as sound
for laboratory use.
sampling, sample-transfer and quality control procedures.
Surface/Separator Sampling
Weatherford Laboratories collects samples throughout the life of a well, as the
fluids analysis at different stages guides important decisions that optimize
production and development planning.
Samples collected during exploration and appraisal are useful for:
Optimizing facilities design
Tuning reservoir simulation models
Appraising the number and the types of wells
(vertical vs. horizontal, production vs. injection, etc.)
Down Hole Sampling
• Samples collected during field development
provide insight into:
Reservoir simulation confirmation studies
Developmental well counts
During production and eventual abandonment,
samples help guide:
Infill programs
Facility upgrades
Enhanced oil recovery programs
Fluid samples collected from the bottom of the wellbore are as close as possible to reservoir conditions, but run the risk of potential mud
contamination. Bottom hole samples are required for wells exhibiting solids drop out like wax/paraffins or asphaltenes. For cased-hole wells,
Weatherford Laboratories employs state-of-the-art down hole sampling tools to get accurate fluid samples with minimum contamination risk.
The sampling tool is first lowered into the cased wellbore. Fluids are then allowed to flow into the tool, and are finally carried to the surface in a safe
and secure manner.
Sampling at surface conditions allows for exact control of sample taking, without placing any restrictions on sample
volumes. The best place to obtain surface samples is from the separator, particularly for reservoir fluids close to or at
the saturation pressure. Weatherford Laboratories has the tools and techniques to accurately collect separate gas and
liquid samples from the separator, and then uses a QA/QC evaluation process on each sample which includes:
Checking opening pressure
Identifying potential solid-forming components for flow assurance purposes
Checking water content of the oil
Performing sample validation on separator samples.
Surface sampling services are available both onshore and offshore, and sample transfers from non-certified sampling
cylinders to DOT/IATA, TPED or TC rated cylinders are routinely performed. All Weatherford Laboratories sampling
personnel are certified for offshore duty and working in H2S environments. The individual samples are then recombined
in the laboratory. This is performed at reservoir pressure and temperature, while ensuring that reliable recombination
parameters including representative gas/oil ratio (GOR) or gas/liquid ratio (GLR), target saturation pressures (bubble
point or dew point) and composition are met.
PVT analysis
EOS modeling
Key data unlocks reservoir fluid properties.
Weatherford Laboratories’ PVT analysis techniques uncover a wealth of knowledge about the fluids in the reservoir, and guide
Volatile Oil
decisions on the best production scenarios for the long-term viability of the well. The key data obtained from PVT reports include
Weatherford Laboratories’ fluid analysis techniques on near-critical,
an understanding of fluid composition, density, viscosity, and compressibility; gas in solution; saturation pressure (bubble point
volatile oil include:
and dew point); and flow assurance properties, to name a few. Weatherford Laboratories has facilities to do comprehensive
analysis on all reservoir types from very low API heavy oils, conventional oils, volatile oil, gas condensate and dry gas. Isolation
labs are available for the safest handling of all H2S and acid gas systems.
Detailed Compositional Analysis of Reservoir Fluid
Constant Composition Expansion (CCE) with liquid volumes
Differential Liberation (DL) with:
• Densities and formation volume factors at each
stage of depletion
Black Oil Analysis
Weatherford Laboratories’ black oil analysis techniques include:
• Detailed Compositional Analysis of Reservoir Fluid
• Constant Composition Expansion (CCE)
• Differential Liberation (DL), with:
• Pressurized viscosity, densities and formation volume factors
at each stage of depletion
• Oil properties and gas-phase properties at each stage of depletion • Separator tests
• Viscosity of Reservoir fluid in both single-phase and 2-phase regions
at Reservoir Temperature
• Oil properties and gas-phase properties at each stage of depletion
• Equation of state modeling
Separator tests
Constant-Volume Depletion (CVD) experiments
Measurement of oil and gas-phase properties
Modeling Fluid Behavior
To be truly impactful on field operations, reservoir fluid analysis cannot stop at merely the data generation step in the lab. A complete
fluid characterization must also include numerical characterization to understand what the data is telling you and to guide your
production optimization and further development decisions.
• Equation of state modeling
To that end, Weatherford Laboratories develops equation of state (EOS) models that use the fluid properties obtained in the lab to
accurately gauge how the reservoir fluids will respond to changes in pressure, temperature and composition. Our EOS models are
Weatherford Laboratories’ gas-condensate analysis includes:
• Constant-Volume Depletion (CVD) experiments, which are constantly updated with new field data—gas and oil compositional analysis, CCE, DL and CVD—and regressions are performed to
performed to simulate reservoir depletion performance and
compositional variation through the well’s life cycle
improve the accuracy and detail of reservoir simulations.
• Produced well-stream property analysis
• Equation of state modeling
Weatherford Laboratories is one of the few service providers that offer this level of EOS modeling, and we have worked with clients
• Detailed Compositional Analysis of Reservoir Fluid
• Constant Composition Expansion (CCE)
with retrograde liquid volumes
around the world to optimize their reservoir simulations for estimating reserves recovery.
flow assurance
Flow assurance—ensuring the successful and economical flow of hydrocarbons from the reservoir to the point of sale—is vital to
Organic Composition
successful long-term operations. Threats to flow assurance include a diverse set of components in the fluid, which under the right
A produced fluid stream’s organic composition tells a great deal about the ability of the
conditions of temperature and pressure may deposit on the internal walls of piping and process equipment to slow or ultimately
hydrocarbon stream to flow at various temperatures and pressures. Analysis includes:
stop flow.
Weatherford Laboratories’ suite of reservoir fluid analysis techniques is designed to identify the various components of the reservoir
fluid that threaten flow assurance. We work with our clients to understand the specific flow assurance problems they want to solve.
From there, we tailor a customized flow assurance test protocol to address their challenges. This is dynamic testing protocol that
constantly evolves as more information becomes available, and the testing continues to be honed until we are satisfied that the
analysis will yield the best and most cost-effective flow assurance solution.
Solids Deposition
The deposition of solid particulates such as asphaltenes, wax/paraffins and
scale can quickly hinder production from a well, and require costly and
time-consuming intervention methods to remedy. Weatherford Laboratories
employs a suite of solids deposition screening tests to evaluate the potential
API gravity
Cloud and Pour point
Cold restart rheology system
Natural Gas Hydrates
The formation of natural gas hydrates is a pervasive problem in deep and ultra-deep
water fields, and can quickly plug off a pipeline or riser if left untreated. Weatherford
Laboratories’ fluid analysis toolkit includes a suite of hydrate formation tests to identify
hydrate formation potential and suggest proper mitigation methods. These include:
• Hydrate stirred autoclave cells
• Cold start rheology system
• Cold stress deposition testing
for these solids to form, and then suggest the appropriate mitigation strategy
Reservoir Fluid
to keep production flowing and avoid an intervention. Current capabilities include:
A thorough understanding of the composition and phase behavior of reservoir fluids
is an important parameter in managing the flow assurance program for any field. And as reservoir fluids from different sections
Asphaltene screening
of a reservoir (or from different wells) commingle, it is vitally important to understand the interaction between fluid streams and
Asphaltene Onset Pressure (AOP)/ Asphaltene Deposition Envelope (ADE)
any potential flow assurance risks to the production system. Weatherford Laboratories has the tools and analytical expertise to
Wax Deposition and Wax Appearance Temperature (WAT)
analyze fluid streams at a fundamental level and their potential for scale, corrosion, asphaltene deposition or hydrate formation.
Scaling/asphaltene tests using tube blocking techniques
Analysis tools include:
HP/HT solids onset (NIR or laser) system with HP microscope
• Fluid/fluid compatibility testing
• Scaling tendency software
• Fluid rheology
• Onset of solids formation
• Onset of solids formation
enhanced oil recovery
We expect more from ourselves
so you can expect more from us.
Enhanced Oil Recovery (EOR)
Storage and Tracking Services
Weatherford Laboratories is the world leader in experience for complex gas injection, thermal operations and testing.
Weatherford Laboratories provides secure and customizable storage solutions for all reservoir fluid samples. We operate custom
Weatherford Laboratories operates the only commercial lab in the world with certified sour gas facilities. Our integrated
on-site facilities for storage and management of pressurized reservoir fluids, separator products and atmospheric liquid samples.
capabilities lead the way in defining and comparing the validity and value of the complete suite of EOR strategies.
Precision analyses and “scalable” results help improve all your EOR requirements from steam flood performance while minimizing
the corrosive impacts of H2S, to correct chemical selections and optimized gas injection schemes. These results yield better
understanding of your reservoir as well as optimized production options. Weatherford Laboratories’ in-depth experience also
encompasses a variety of plays in a range of reservoir types worldwide, allowing us to apply our science and technology to
support your program from the pore-scale to field-scale.
on-site in situ solutions so that hydrocarbon recovery and revenue are enhanced to the greatest extent possible.
• Multi-contact Experiment
Quantify IFT, viscosity, solubility associated K values, Bo
& Rs result in accurate modeling of the vaporizing and/or condensing processes that occur in the actual reservoir
• Constant IFT Core Flooding
No mass transfers during the constant IFT core flood result in true residual oil recovery and none of the core stack is used for establishing a miscible bank
• Acid Gas Testing for Applicability
to EOR & Sequestration
The isolation lab permits the testing of any (lab) volume at any pressure/temperature of acid gas for sequestration or EOR applications in a safe and effective manner.
• Chemical Flooding
depending on the sample requirements. The storage facilities are secure, with access restricted to authorized personnel only, and
monitored continuously with security cameras and hydrocarbon sensors—an important requirement for the storage of sample gases
and toxic reservoir gases.
And to provide maximum safety for your samples and assurance that they are right where they are supposed to be, Weatherford
Higher Weatherford Laboratories’ standards of interpretation and integration with field processes improve the flexibility of your
Storage facilities are climate controlled to a range of a temperatures including ambient, air-conditioned, chilled/frozen and heated,
Screening & optimization of chemical flood reservoir candidates
Laboratories’ Sample Management Tracking System uses sophisticated data management tools, including bar coding options, to track
movement of your materials. Sample inventories can also be made available via our secured client websites.
Brisbane, Australia
Telephone: +61.7.3482.9900
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Telephone: 832.237.4000
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