Production of Natural Gas and Fluid Flow in Tight Sand Reservoirs
To study the influence of microscopic flow mechanisms on gas production parameters of tight sand reservoirs.
The main goal of this research is to identify possible relationships and define dependencies between macroscopic reservoir parameters strongly affected by microscopic flow dynamics and production well performance in tight-gas sand reservoirs. To achieve this goal, the Center for Energy and Technology of the Americas (CETA) will identify microscopic flow mechanisms that affect fluid flow by using pore network simulation and other modeling techniques, that when coupled to homogenization and upscaling tools, can be used to find average macroscopic equations that properly describe the fluid flow behavior at the laboratory scale. The formulation can then be further extended for application at field scales by using dynamic upscaling methods upon determination of reservoir heterogeneity. Subsequently, CETA will evaluate the impact of reservoir features on fluid flow. Such features could be fluid properties, reservoir depth, net sand thickness, reservoir permeability, and data from drilling and stimulation processes.
Florida International University, Center for Energy and Technology of the Americas (CETA)
Miami, Florida 33174
The influence of microscopic flow mechanisms on gas production parameters in tight sand reservoirs can help identify possible relation-ships and dependencies between macroscopic reservoir parameters and well performance. Subsequently, these parameters can be used in the development of rigorous, macroscopic equations that more accurately describe the fluid flow behavior in tight-gas reservoirs and allow operators to better assess well completion strategies, predict well performance, and avoid tight-gas well production problems, such as unexpected associated water production.
Current Status and Remaining Tasks:
Ongoing or remaining tasks associated with this study include:
Project Start: June 30, 2004
Project End: June 30, 2006
DOE Contribution: $111,050
Performer Contribution: $0
NETL – Tom Mroz (Thomas.Mroz@netl.doe.gov or 304-285-4071) or
FIU ? Dr. Maria Brazo (firstname.lastname@example.org or 305-348-1821)
Paper Title: A novel modeling approach for two-phase fluid flow in tight sand gas reservoirs
Paper Abstract: A system of macroscopic transport equations that model two-phase (gas-water) flow through tight porous media is presented. The porous medium is modeled using a dual-porosity and dual-permeability approach. Phenomena such as, Knudsen diffusion, electro-kinetic effects, diffusion of dissolved gas in water and water vaporization have been captured in the proposed formulation. The transport equations were discretized in a 2D finite differences scheme and solved numerically. Results are compared with other single and multi-mechanistic approaches commonly used for tight sand reservoirs. We analyze the model predictions for various reservoir properties, initial conditions and exploitation strategies. We observe differences in the predicted gas production from the models considered and the common underestimation when using a single-mechanistic approach. We also present results that possibly explain unexpected water production.