Material Balance, Modeling and Simulation: Reservoir Engineering Tools Past, Present and Future
Registration: 8:00 a.m. - 9:00 a.m.
9:00am – 10:15am – Dr. John McMullan , Marathon Oil Company
“Material Balance: The Forgotten Reservoir Engineering Tool”
Material balance as a reservoir engineering tool has lost popularity in recent years with the widening use of reservoir simulation; however reservoir simulation is based upon the fundamental assumption of material balance. Is there a place for traditional material balance analysis in the reservoir engineering “tool kit”, or is it, as some have suggested, a “needless distraction” to the modern engineer? With modern computer software, material balance analysis often requires only minutes. Material balance is quick, often straightforward, and can provide a valuable understanding of the reservoir. This understanding of the reservoir has the potential to accelerate the history matching phase in a reservoir simulation study. There is no logical reason not to consider material balance for reservoir analysis. This talk reviews the development and application of material balance, and uses several examples to illustrate its usefulness to the reservoir engineer.
10:30am – 11:45am – Dr. Bill McCain, Texas A. & M. University
“Rapid ‘Tuning’ of Equations of State in Compositional Simulation”
A graduate school project over the last several years at Texas A & M University has worked to take some of the mystery out of ‘tuning’ equations of state for use in compositional simulation. A strategy has been proposed which appears to automatically work for any gas-condensate or near-critical/volatile oil. This strategy performs the tuning by altering the least accurately known properties of the fluid. The best technique for extending the lab measured composition of the plus fraction was determined. A major outcome of this work is an understanding that the method of grouping the compositions of the multiple carbon number groups from the extended composition is dependent on the composition of the measured plus fraction of the original reservoir fluid.
11:45am – 1:00pm Lunch (provided)
1:00pm – 2:15pm Dr. Chris White, Louisiana State University
“Emerging Uses of Reservoir Simulation: Insights, Planning, and Control”
The future of simulation will provide information never before available, but will also require more discipline, forethought and limitations. This presentation will discuss how new methods and hardware allow us to do sensitivity and history matching (insights), optimization and scenario modeling (planning), and eventually guide day-to-day decision making and operations (control). The presentation will focus not so much on theory, but rather on applications and operations.
2:30pm – 3:45pm Mr. Rob Sutton , Marathon Oil Company
“Variations in Modeling with PVT Correlations and Effects on Reservoir Performance Estimates”.
At the PTTC/Core Lab symposium of 2004, Dave Bergman presented a discussion of oil viscosity correlations, and their accuracy and pitfalls if an unsuitable method is selected to represent a given crude oil. Ideally PVT properties are known; however, in situations where PVT is an unknown, correlations are utilized. The talk for 2005 has been expanded to discuss PVT methods for the calculation of the major oil properties of interest for engineers. In particular, these properties include bubble-point pressure, oil formation volume factor, isothermal compressibility, and viscosity. A conceptual black oil reservoir model was created to test these methods and access the impact of this variability on original oil in place, reservoir performance, oil recovery and project life. Oil properties over the range of 20-40 API and gas-oil ratios of 250-750 scf/STB at a reservoir temperature range of 125-250 °F were evaluated.