3-D Printing Artificial Reservoir Rocks to Test Their Petrophysical Properties
At present, pore-scale imaging and modeling are becoming routine geoscience techniques of reservoir simulation in oil and gas industry. The foundation of these techniques is the development of sophisticated three-dimensional models that can represent both the multiphase flow dynamics and the geometry of the rock's pore system. Three-dimensional printing may facilitate the transformation of pore-space imaging into rock models, which can be tested using traditional laboratory methods to provide data that is easily comparable to literature data. Although current methodologies for rapid rock modeling and printing obscure many details of rock geometry, computed tomography data is one route to refine pore networks and experimentally test hypotheses related to rock properties, such as porosity and permeability. This study uses three-dimensional printing as a novel way of interacting with a) x-ray computed tomography data from reservoir rocks and b) mathematical models of pore systems in coarse-grained sandstones and limestones. These artificial rocks will be used as a proxy to better understand the contributions of various pore system characteristics at various scales to petrophysical properties in oil and gas reservoirs. Pore sizes of typical reservoir sandstone range from 0.1 to 100s of microns. The resolution of three-dimensional digital printing used in the study varied from 16 to 300 microns, therefore, the three-dimensional imaging and especially printing might have lost information on pore geometry. The increase in scale of the pore systems (e.g. from 1 micron in reality to 50 microns in a three-dimensional model) will be a key factor for a precise determination of porosity-permeability relationships as they can be verified against core-scale measurements. The long-term goal of this study is to focus on testing of petrophysical hypotheses by manipulating digital rock models to determine the resulting changes in artificial rock properties that affect fluid flow. If the pore system models could include tools for adequate measurements of petrophysical properties in “manufactured” rocks in the laboratory conditions, the accuracy of reservoir flow simulations would be increased. Three-dimensional printing offers a great potential to improve our approach to reservoir simulation, facilitating more efficient oil and gas recovery.
AAPG Datapages/Search and Discovery Article #90189 © 2014 AAPG Annual Convention and Exhibition, Houston, Texas, USA, April 6–9, 2014