Current Status and Screening Criteria for Field Application of Short-Distance Oil Displacement Methods

Alex T. Turta¹, Ashok K. Singhal¹, Tianxiang Xia², and Malcolm Greaves^2
1 Alberta Research Council, Calgary, AB
² University of Bath, Bath, England
 

Reservoir engineering aspects of selecting and implementing Short-Distance Oil Displacement (SDOD) methods for heavy, extra-heavy oil and oil sand reservoirs are discussed. More precisely, this presentation deals with the current status and guidelines for selection of SDOD processes for oil reservoirs with in-situ oil viscosity greater than 100 mPas.

The following SDOD processes are considered: - Steam Assisted Gravity Drainage (SAGD) - Cyclic Steam Stimulation (CSS) and Single Well SAGD - Toe-to-Heel THermal Methods (THAI/CAPRI) - Vapex - CO₂ Huff 'n Puff - TTH Waterflooding (Gravity Stable Waterflooding)

Updated screening criteria are formulated for commercially developed methods (CSS, CO₂ huff 'n puff and SAGD), based on the available data on field performance. Where possible, criteria are also proposed for cases where these methods are intended for cold heavy oil production (foamy solution gas drive with or without massive sand influx, modifying in-depth the state of reservoir). More specifically, the effect of wormholes on performance and control of different SDOD processes are reviewed.

For the emerging SDOD technologies -- Vapex, thermal and non-thermal (gravity stable waterflooding) toe-to-heel displacement methods -- which are either under field piloting or planning stages -- preliminary screening criteria are presented, based on insights from laboratory investigations, simulation work and some information on field piloting.

Horizontal wells can considerably enhance performance for all SDOD processes, but an effective means of controlling production of the injected fluid is essential. New ways to achieve effective control on the movement of displacement fronts are discussed for various well configurations, including the combined use of horizontal and vertical wells.

AAPG Search and Discovery Article #90039©2005 AAPG Calgary, Alberta, June 16-19, 2005