Reservoir Fluid Sampling and Characterization—Key to Efficient ReservoirManagement

Abstract

Reservoir Fluid Sampling and Characterization—Key to Efficient Reservoir Management Narayana Rao Nagarajan; Narayana Rao Nagarajan Search for other works by this author on: This Site Google Scholar Mehdi Matt Honarpour; Mehdi Matt Honarpour Search for other works by this author on: This Site Google Scholar Krishnaswamy Sampath Krishnaswamy Sampath ExxonMobil Upstream Research Co. Search for other works by this author on: This Site Google Scholar Paper presented at the Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, UAE, November 2006. Paper Number: SPE-101517-MS https://doi.org/10.2118/101517-MS Published: November 05 2006 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Nagarajan, Narayana Rao, Honarpour, Mehdi Matt, and Krishnaswamy Sampath. "Reservoir Fluid Sampling and Characterization—Key to Efficient Reservoir Management." Paper presented at the Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, UAE, November 2006. doi: https://doi.org/10.2118/101517-MS Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentAll ProceedingsSociety of Petroleum Engineers (SPE)Abu Dhabi International Petroleum Exhibition and Conference Search Advanced Search AbstractReservoir fluid properties play a key role in the design and optimization of production processes and facilities for efficient reservoir management. Inaccurate and unreliable fluid characterization leads to high uncertainties in in-place hydrocarbon volume estimates, negatively impacting ultimate recovery predictions and hence the asset value. Obtaining reliable PVT properties of reservoir fluids starts with the acquisition of adequate volumes of representative fluid samples followed by PVT data measurement and phase behavior modeling. Subsequent laboratory analysis should be monitored through established quality control procedures to provide high quality data. The fluid characterization methodology should employ best-practice techniques to model fluid behavior as functions of pressure, temperature, and fluid composition. In this paper, we discuss key steps in sampling and fluid characterization for a wide spectrum of fluid types ranging from extra-heavy oils to lighter gas-condensates including complex near-critical fluids. Using several field examples, sampling tool design and procedures for obtaining representative samples are discussed. Laboratory fluid analysis strategies for various fluid types are highlighted with an emphasis on employing quality control and quality assurance procedures. The importance of special PVT tests to capture fluid behavior under different production strategies ranging from simple depletion to complex tertiary recovery is emphasized. Application of recommended fluid modeling techniques such as C7+ characterization and Gibb's energy minimization are demonstrated through field examples.IntroductionReservoir fluid PVT properties play a major role throughout the life of the reservoir from the discovery to abandonment. Reliable PVT properties of in situ fluids are essential for the determination of in-place volumes and recovery factor calculations. In addition, PVT properties are key input to simulations for evaluating reservoir development/depletion plans. Fluid characterization and distribution within the reservoir help in defining reservoir continuity and communication within various zones. Accurate fluid PVT properties are required for the interpretation of well test data and the design of surface facilities and processing plants. Therefore, it is critical to obtain representative samples and reliable PVT data for fluids characterization. Periodic updating of fluid properties, their distribution, and their changes with reservoir production is a necessary step in reservoir surveillance to optimize the production/injection strategies.Reservoir fluid characterization consists of several major components: acquisition of representative samples, identification of reliable service laboratories to perform PVT measurements, implementation of quality assurance/quality control (QA/QC) procedures to ensure data quality, and finally development of equation of state (EOS) models to accurately capture fluid property changes as functions of pressure, temperature, and composition. The reservoir fluid type dictates the steps involved in fluid characterization. The reservoir development and production processes necessitate that these steps are further customized to development and production plans. This paper outlines recommended fluid sampling techniques, PVT data acquisition strategies, and fluid modeling methods based on fluid type and production processes. Several field examples covering different fluid types, heavy oils, black oils, near-critical fluids, and gas-condensates, and production processes are presented to illustrate the importance of representative sampling and reliable fluid characterization. Keywords: enhanced recovery, fluid type, Modeling & Simulation, equilibrium, PVT measurement, concentration, selection, calculation, composition, procedure Subjects: Fluid Characterization, Improved and Enhanced Recovery, Phase behavior and PVT measurements This content is only available via PDF. 2006. Society of Petroleum Engineers You can access this article if you purchase or spend a download.