Near-Wellbore Permeability Damage by Fines Migration in Steam Assisted Gravity Drainage Wells

• Author / Creator

  Miri, Rahman

• This thesis investigates the flow performance impairment or permeability damage under the fines migration process near the SAGD wellbore producers completed with sand control screens. A new sand retention testing (SRT) procedure was developed to replicate a more representative fines migration process in SAGD wellbore conditions to evaluate the flow performance of sand control screens. The investigation factors included different sand control screen specifications, flow rate, flow salinity, fines content, and sand and fine particles size distributions. The research was conducted in two experimental and numerical stages.
  The first stage comprised extensive SRT experiments to investigate the hydrodynamic and chemical effects of the fines migration process, evaluate the reliability of previous testing procedures for replicating representative fines migration process in SRT experiments, and troubleshoot the set-up deficiencies.
  The experimental results indicated a non-monotonic behavior of permeability with an initial decrease followed by an increasing trend for the near screen interval of the sand pack, inconstant with core flooding and field observations. This behavior was attributed to the dominant effect of releasing fine particles from or near the pore throats compared with retaining fine particles over the thin pore throats by the hydrodynamic effects only. A monotonic decreasing behavior of the permeability was observed under the chemical effect of the fines migration when high saline saturating fluid was displaced with a low saline brine, representing near SAGD wellbore conditions. The sand screens with a low open flow area and narrow aperture caused high permeability loss under the same flow conditions. Higher salinity reduction yielded higher mobilized fines concentration, causing high permeability loss of the sample.

  A laboratory-based numerical modeling approach was conducted in this research to simulate the fines migration process in the SRT setup, considering the sand screen geometry. With sufficient accuracy, the model could match the observed dimensionless pressure drops at different sample intervals. The model incorporated four calibration parameters concerning filtration of fine particles at pore throats, fine particles velocity, and the empirical permeability loss correlation parameters. The model calibration results confirmed that the matching parameters were nearly independent of the sand screen. However, they were different for different flow salinities, confirming their dependency on flow properties along with the porous media.

• Subjects / Keywords

  • Fines Migration
  • Permeability Damage
  • Steam Assisted Gravity Drainage (SAGD)
  • Sand Control Screen

• Graduation date

  Fall 2022

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/r3-y23z-8y53

• License

  This thesis is made available by the University of Alberta Library with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.