Reservoir Fluids Phase Behavior and PVT Analysis
Fluid samples taken to a laboratory provide the only way to study volumetric behavior and chemical properties of formation fluids. Objective of a Pressure-Volume-Temperature (PVT) study is to determine the physical and chemical fluid characteristics to predict its behavior versus pressure and temperature changes. A PVT study is used to evaluate the hydrocarbon in place at surface conditions, simulate the reservoir fluid behavior during all production processes, and build a production profile associated with a development plan.
Texas OilTech Laboratories offers both standard and advanced PVT testing packages for black oil, volatile oil, and gas condensate.
Standard PVT Package
Texas OilTech Laboratories’ testing capabilities offers a series of standard testing for Reservoir Fluid Studies. This package includes the following:
- Quality check of the bottomhole and separator fluid samples
- Physical recombination of separator oil and separator gas samples
- Compositional analysis of oil and gas samples
- Separator tests
- Single-stage separator tests
- Constant composition expansion (CCE)
- Constant volume depletion (CVD)
- Differential liberation expansion (DLE)
- Multi-stage separator tests
- Separator optimization studies
- Viscosity measurements
- Real-world reservoir conditions—up to 400 oF and 15,000 psi pressure
Standard PVT Study
Texas OilTech Laboratories is an ISO certified laboratory specializing in reservoir fluids analysis (PVT testing). Our ability to create world reservoir conditions – up to 400 °F (200 °C) and 15,000 psi (100 MPa) – enables us to handle difficult problems and to customize analytical testing capabilities that are beyond the scope of other laboratories.
Advanced PVT Package
To design a successful miscible gas injection project, one must understand the mechanisms by which the injected gas displaces oil in the porous medium. There are two major variations in this process: First contact miscibility (FCM) process and Multiple contact miscibility (MCM) process.
Texas OilTech Laboratories’ testing capabilities offers a series of advanced PVT testing to study miscibility mechanisms in Enhanced Oil Recovery (EOR) by gas injection. This package includes the following:
- Swelling tests (P-x diagram)
- Multiple contact tests
- Rising Bubble Apparatus (RBA)
- Slimtube experiments
- Interfacial tension measurements
Equation of States (EOS) Modelling and Characterization
PVT laboratory measurements are made on only a small portion of the composition path encountered throughout the displacement, whereas an EOS can be used to predict behavior for the entire composition path and pressure range of the process. The accuracy of any EOS model depends on the quality of the laboratory PVT data and procedures used to obtain the EOS parameters.
The EOS characterization and modeling of fluid phase behavior in the P-V-μ envelope at reservoir temperature is mostly determined by matching the PVT data from the Standard PVT Package, while the EOS characterization and modeling of fluid phase behavior in the entire (P –V – T – μ – zi – Ki – σgo) envelope requires PVT data from the Advanced PVT Package.
Texas OilTech Laboratories’ software capabilities offers advanced EOS modelling and characterization for compositional reservoir simulation purposes.
