Thermal Recovery of Bitumen from the Grosmont Carbonate Formation - Part 1: The Saleski Pilot
Authors: Daniel Yang, Chief – Reservoir Engineering – Laricina Energy Ltd., Moslem Hosseininejad – Reservoir Engineer – Laricina Energy Ltd., and Jeff MacDonald, Osum Oil Sands Corp.
Source: Journal of Canadian Petroleum Technology – July 2014, Volume 53, Issue 04
At the Saleski Pilot in Alberta, Canada, steam was injected into the Grosmont Formation, a naturally fractured bitumen bearing carbonate reservoir, and it was demonstrated that bitumen can be produced at commercial rates with favourable steam-oil ratios. The pilot has also helped define the optimal design criteria for surface facilities, well drilling, well completions, and operational strategies for commercialization.
In the pilot’s first year, continuous injection and production using well pairs, similar to successful Steam Assisted Gravity Drainage projects in Alberta oil sands, revealed the difficulty of achieving stable operations in this naturally fractured reservoir. Cyclic operation in the second phase lead to improved bitumen rates and lower steam oil ratios.
The Grosmont carbonate exhibits excellent steam injectivity with full well conformance and lateral heat containment around the wells. Superior performance of a well drilled with balanced conditions, completed open hole and treated with acid in stages compared with wells drilled over-balanced, completed with slotted liners and washed with acid at the toe and the heel, confirms the significance of well design on thermal project performance.