Special Core Analysis

Course Content

• INTRODUCTION

  • Business value of SCAL, remaining vs. residual oil saturation, wettability.
  • Best practice: need for interpretation-by-simulation.
  • General overview of laboratory measurement techniques.

• STEADY-STATE TECHNIQUE

  • Basics: experimental set-up in the lab, physics of the experiment, horizontal vs. vertical, automation of data gathering.
  • Analytical interpretation: data consistency, design of experiments, choices for fractional flow.
  • Best practice: interpretation-by-simulation, hands-on exercises using the SCORES/DuMux simulator.
  • Residual oil vs. remaining oil saturation, impact of imbibition capillary pressure, oil end-effect.
  • Impact of drainage capillary pressure, water end-effect.

• CORE PLUG PREPARATION & UNSTEADY-STATE TECHNIQUE

  • Core plug preparation:
  • Plug selection, using quantitative X-ray CT images, cleaning.
  • Establish initial water saturation:
  • Mercury injection (MICP) for reservoir saturation height functions and pore size distribution.
  • Recent developments in MICP showing important problems in MICP for low permeability rock when assessing transition zones.
  • Ageing.
  • Unsteady-State (Welge) technique:
  • Basics: experimental set-up in the lab, physics of the experiment, horizontal vs. vertical, automation of data gathering; analytical interpretation with exercises in Excel™.
  • Analytical calculation of shock front saturation, JBN method.
  • Corey parameter characterization.
  • Best practice: interpretation-by-simulation, hands-on through exercises with the SCORES/DuMux simulator: effect of viscosity ratio, impact of capillary forces, capillary number and desaturation.

• CENTRIFUGE TECHNIQUE & SCAL DATA QUALITY ASSESSMENT

  • Centrifuge technique:
  • Basics: experimental set-up in the lab, physics of the experiment, drainage vs. imbibition hardware, automation of data gathering.
  • Analytical interpretation with exercises in Excel™. Bond number:
  • Hassler-Brunner analysis for multi-speed experiments.
  • Hagoort analysis for single-speed experiments.
  • Best practice: interpretation-by-simulation, hands-on through exercises with the SCORES/DuMux simulator:
  • Effect of oil viscosity, characteristic time.
  • Impact of water mobility in imbibition experiments.
  • Impact of capillary forces.
  • History matching multi- and single-speed experiments.
  • SCAL quality assessment:
  • How to recognize bad data?
  • Best practice: verifying data consistency.
  • Implement SCAL data into reservoir simulation studies:
  • Rock-typing.
  • Gridding for reservoir simulation.

• POROUS PLATE TECHNIQUE, SCAL FOR GAS FLOODING EXPERIMENTS, STRENGTHS & WEAKNESSES OF EACH SCAL TECHNIQUE

  • Porous plate technique - Basics:
  • Experimental set-up in the lab, physics of the experiment, capillary continuity, multiple plugs vs. single plug equipment.
  • Automation of data gathering.
  • Analytical interpretation with exercises in Excel™: recognizing equilibrium, characteristic time.
  • Best practice: interpretation-by-simulation, hands-on through exercises with the SCORES/DuMux simulator.
  • How to set-up simulations in the absence of data?
  • Experimental design.
  • Interpretation-by-simulation of capillary pressure and resistivity measurements.
  • SCAL for gas flooding experiments:
  • Understand limitations of UnSteady-State and Steady-State techniques through exercises in Excel:
  • Impact of shock front in drainage and imbibition mode in UnSteady-State experiments.
  • Hagoort criterion for viscous fingering.
  • 3-phase relative permeabilities, spreading condition, centrifuge experiments for GOGD.
  • Best practice: interpretation-by-simulation, hands-on through exercises with the SCORES/DuMux simulator: impact of capillary pressure in flooding experiments.
  • Plenary discussion of strength and weaknesses of each SCAL measurement technique.
  • Understanding main characteristics of each technique facilitates designing a lean and fit-for-purpose SCAL measurement program.

• SCAL FOR EOR & SCAL MASTER MEASUREMENT PROGRAM

  • SCAL for EOR:
  • Introduction into EOR techniques in the field.
  • Understanding scope for EOR.
  • Issues and design of SCAL experiments for low salinity flooding, Microbial EOR, CO₂ EOR, Thermal EOR, Chemical EOR, EOR in fractured reservoirs.
  • Plenary discussion on the design of a best practice master measurement program:
  • At the end of this discussion, a comprehensive handout will be distributed that serves as a Master SCAL measurement program for future use in the office.