TY  - JOUR
KW  - Adsorption isotherms; Boundary conditions; Computer system recovery; Desorption; Flow of gases; Low permeability reservoirs; Navier Stokes equations; Petroleum reservoir engineering; Pore size; Shale gas
KW  -  Gas desorption; Pore-network modeling; Shale gas reservoirs; Slip flow; Stokes flows
KW  -  Gases
KW  -  desorption; gas flow; hydrocarbon reservoir; modeling; permeability; shale gas; Stokes formula
ID  - scholars11779
N2  - Shale reservoirs are characterized by very low permeability in the scale of nano-Darcy. This is due to the nanometer scale of pores and throats in shale reservoirs, which causes a difference in flow behavior from conventional reservoirs. Slip flow is considered to be one of the main flow regimes affecting the flow behavior in shale gas reservoirs and has been widely studied in the literature. However, the important mechanism of gas desorption or adsorption that happens in shale reservoirs has not been investigated thoroughly in the literature. This paper aims to study slip flow together with gas desorption in shale gas reservoirs using pore network modeling. To do so, the compressible Stokes equation with proper boundary conditions was applied to model gas flow in a pore network that properly represents the pore size distribution of typical shale reservoirs. A pore network model was created using the digitized image of a thin section of a Berea sandstone and scaled down to represent the pore size range of shale reservoirs. Based on the size of pores in the network and the pore pressure applied, the Knudsen number which controls the flow regimes was within the slip flow regime range. Compressible Stokes equation with proper boundary conditions at the poreâ??s walls was applied to model the gas flow. The desorption mechanism was also included through a boundary condition by deriving a velocity term using Langmuir-type isotherm. It was observed that when the slip flow was activated together with desorption in the model, their contributions were not summative. That, is the slippage effect limited the desorption mechanism through a reduction of pressure drop. Eagle Ford and Barnett shale samples were investigated in this study when the measured adsorption isotherm data from the literature were used. Barnett sample showed larger contribution of gas desorption toward gas recovery as compared to Eagle Ford sample. This paper has produced a pore network model to further understand the gas desorption and the slip flow effects in recovery of shale gas reservoirs. © 2018, Springer Nature B.V.
IS  - 3
Y1  - 2019///
VL  - 126
UR  - https://www.scopus.com/inward/record.uri?eid=2-s2.0-85053528922&doi=10.1007%2fs11242-018-1147-6&partnerID=40&md5=c092d705151db36a11ba39401c1d889f
A1  - Foroozesh, J.
A1  - Abdalla, A.I.M.
A1  - Zhang, Z.
JF  - Transport in Porous Media
AV  - none
SP  - 633
TI  - Pore Network Modeling of Shale Gas Reservoirs: Gas Desorption and Slip Flow Effects
N1  - cited By 25
SN  - 01693913
PB  - Springer Netherlands
EP  - 653
ER  -