Three-Phase Flow Simulation in Ultra-Low Permeability Organic Shale via a Multiple Permeability Approach

This paper proposes a novel approach to model multiphase flow of hydroca rbons in unconventional shale reservoirs. Understanding the storage/flow mechanisms from such reservoirs as in the Eagle Ford, Woodford, and Bakken, is crucial in the overall effort to increase the ultimate hydrocarbon production . Based on the geological evidence, three different pore systems with distinctive storage/transport characteristics hav e been recognized in the shale reservoirs inorganic medium, kerogen (or organic matter), and natural/hydraulic fractures. Our simulation results show that compared to oil, gas recovery in shale reservoirs can be more efficient due to a dual Darcy/diffusive flow mechanism of the gas phase (as a result of molecule-wall collisions). Darcy flow is considered as the only flow means for the liquid phase transport in such reservoirs. Although oil-wet kerogen is considered to be a rich source of hydrocarbon, nano-darcy permeability of the rock hinders oil pro duction in organic-rich shale. Our sensitivity analysis shows that considering diffusive flow will increase gas recovery by facilitating gas transport in kerogen. On the other hand, although increasing adsorption capabilities in the rock means more hydrocarbon is stored in the organic carbon, the oil-wet nature of the hydrocarb on-saturated kerogen will control the depletion process in this media. Therefore, the limited pressure decrease in the kerogen reduces the effects of hydrocarbon desorption on oil and gas recovery.

[1]  F. Javadpour Nanopores and Apparent Permeability of Gas Flow in Mudrocks (Shales and Siltstone) , 2009 .

[2]  Mehran Sohrabi,et al.  A Review of Recent Developments and Challenges in Shale Gas Recovery , 2012 .

[3]  R. Loucks,et al.  Morphology, Genesis, and Distribution of Nanometer-Scale Pores in Siliceous Mudstones of the Mississippian Barnett Shale , 2009 .

[4]  I. Akkutlu,et al.  Pore-Size Dependence of Fluid Phase Behavior and Properties in Organic-Rich Shale Reservoirs , 2013 .

[5]  Yalchin Efendiev,et al.  Nonlinear Complexity Reduction for Fast Simulation of Flow in Heterogeneous Porous Media , 2013, ANSS 2013.

[6]  Kamy Sepehrnoori,et al.  Steam-Surfactant-Foam Modeling in Heavy Oil Reservoirs , 2014 .

[7]  M. Curtis,et al.  Structural Characterization of Gas Shales on the Micro- and Nano-Scales , 2010 .

[8]  John Killough,et al.  A New Approach for the Simulation of Fluid Flow In Unconventional Reservoirs Through Multiple Permeability Modeling , 2013 .

[9]  I. Akkutlu,et al.  Pore-Size Dependence of Fluid Phase Behavior and the Impact on Shale Gas Reserves , 2013 .

[10]  Faruk Civan,et al.  Shale-Gas Permeability and Diffusivity Inferred by Improved Formulation of Relevant Retention and Transport Mechanisms , 2011 .

[11]  K. Aziz,et al.  Petroleum Reservoir Simulation , 1979 .

[12]  M. Curtis,et al.  Microstructural investigation of gas shales in two and three dimensions using nanometer-scale resolution imaging , 2012 .

[13]  John Killough,et al.  Beyond Dual-Porosity Modeling for the Simulation of Complex Flow Mechanisms in Shale Reservoirs , 2013, ANSS 2013.

[14]  Farzam Javadpour,et al.  Numerical Simulation of Shale-Gas Production: From Pore-Scale Modeling of Slip-Flow, Knudsen Diffusion, and Langmuir Desorption to Reservoir Modeling of Compressible Fluid , 2011 .

[15]  M. Alfi,et al.  Impact of Light Component Stripping During CO2 Injection in Bakken Formation , 2014 .

[16]  John Killough,et al.  Quantifying the Impact of Petrophysical Properties on Spatial Distribution of Contrasting Nanoparticle Agents in the Near-Wellbore Region , 2014 .

[17]  K. Kruk,et al.  SOCIETY OF PETROLEUM ENGINEERS OF AIME , 1997 .

[18]  E. Gildin,et al.  Reduced Order Modeling In Reservoir Simulation Using the Bilinear Approximation Techniques , 2014 .

[19]  Carl H. Sondergeld,et al.  New Pore-scale Considerations for Shale Gas in Place Calculations , 2010 .

[20]  Carl H. Sondergeld,et al.  Micro-Structural Studies of Gas Shales , 2010 .

[21]  T. Tsotsis,et al.  Pore-Scale Characterization of Oil-Rich Monterey Shale: A Preliminary Study , 2013 .

[22]  John Killough,et al.  Beyond dual-porosity modeling for the simulation of complex flow mechanisms in shale reservoirs , 2013, Computational Geosciences.

[23]  M. Sherafati,et al.  Investigation of the Effect of Water Based Nano-Particles Addition on Hysteresis of Oil-Water Relative Permeability Curves , 2012 .

[24]  Haishan Luo,et al.  Polymer flooding of a heavy oil reservoir with an active aquifer , 2014 .

[25]  Quinn R. Passey,et al.  From Oil-Prone Source Rock to Gas-Producing Shale Reservoir - Geologic and Petrophysical Characterization of Unconventional Shale Gas Reservoirs , 2010 .

[26]  Kristian Jessen,et al.  Simulation of Waterflooding with Coarse-Scale Dual-Porosity Representation of Highly Heterogeneous Reservoirs , 2013 .

[27]  Kamy Sepehrnoori,et al.  Simulation Study of CO2 Huff-n-Puff Process in Bakken Tight Oil Reservoirs , 2014 .

[28]  Tongwei Zhang,et al.  Effect of organic-matter type and thermal maturity on methane adsorption in shale-gas systems , 2012 .

[29]  John Killough,et al.  Novel Approaches for the Simulation of Unconventional Reservoirs , 2013 .

[30]  Christopher R. Clarkson,et al.  Reservoir Engineering for Unconventional Reservoirs: What Do We Have to Consider? , 2011 .

[31]  Hassan Mahani,et al.  Generation of Voronoi Grid Based on Vorticity for Coarse-Scale Modeling of Flow in Heterogeneous Formations , 2010 .

[32]  Fred P. Wang,et al.  Pore Networks and Fluid Flow in Gas Shales , 2009 .

[33]  R. H. Brooks,et al.  Hydraulic properties of porous media , 1963 .