STEAM ASSISTED GRAVITY DRAINAGE (SAGD)

Conventional steam assisted gravity drainage requires horizontal well pairs, consisting of a steam injection well and producing well. The injection well is typically located five meters above the producing well. The steam heats the bitumen and aids in the drainage to the production well via gravity and a pressure differential.

STEAM ASSISTED GRAVITY DRAINAGE SLOTTING CONSIDERATIONS

When designing a slot size for any type of liner application, consideration of the effects of the load bearing sands in the formation are most important. The load bearing sands of the formation are the particles we want to be retained by a specific slot size. Once these load-bearing sands have been retained, their new pore throats will then bridge the finer sands in the formation. Initial design criteria is based on a sieve analysis of the formation sands, as well as past experience where applicable. We have also designed single well SAGD applications, and vertical steam injection applications.

FOUR STEP DRAINAGE PROCESS

1. Each well gets drilled.

2. A slotted liner is installed.

3. Steam is pumped into the ground in the upper well.

4. Oil drains to the lower producing well via gravity and a pressure differential.