Experimental Investigations for SAGD Well Integrity Numerical Modelling

• Author / Creator

  Li, Xiangyu

• Steam-Assisted Gravity Drainage (SAGD), today is the most promising technique to extract heavy oil from oil sands reservoirs. Maintenance of integrity of the near-well area is crucial to help ensure that the reserves are produced properly without environmental or production optimization challenges. The research presented here addresses the geomechanical effects associated with SAGD on wellbore integrity. The output of this research can be used in coupled hydraulic-geomechanical numerical simulation platforms for assessing the possible displacement ranges of wellbores within the steam chamber in the large reservoir model. The thesis consists of two parts. In the first part, the hydro-mechanical behavior of Wabiskaw formation located in the SAGD reservoir production site in Canada is experimentally analyzed through consolidation and steady state flow tests. Pressure-dependent compressibilities and Biot coefficients were also obtained from the caprock testing strategy. Significant ‘creep’ behavior was observed during the experiments process. Several possible microscale processes are presented and discussed. In the second part of the thesis the permeability of well cement is characterized through a hydraulic pulse test technique. This work includes: laboratory testing system design, construction and calibration. A parameter identification method based on a previously published analytical solution which describes the pulse behaviour was used to obtain the best estimates of the cement permeability and specific storage. The validity of the technique is evaluated with 22 separate measurements on one well cement sample. The pulse test successfully estimates the cement permeabilities which are in good agreement with steady state flow results. A simple method to interpret the pulse test data is also included in the thesis, and the results were compared with the analytical solution. Numerical simulations of the cement pore pressure decay response generated with the numerical code COMSOL are presented as well.

• Subjects / Keywords

  • SAGD
  • Pulse Test
  • Consolidation
  • Well Integrity

• Graduation date

  Fall 2017

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3XD0R92G

• License

  This thesis is made available by the University of Alberta Libraries 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.