Stability of THAI™ process: Theoretical and experimental observations

The performance of the THAI™ process has been investigated in numerous 3D experiments, using heavy crudes and Athabasca oil sands bitumen. The stability of the process is demonstrated by high combustion zone temperatures, absence of gas channelling, insensitivity to large changes in air injection rate, tolerance of an overlying gas cap, increased combustion temperature and faster upgrading response with increasing oil layer thickness, 'controlled gas override', own 'front tracking' capability and steady oil production rate. The most important parameters for upscaling of (stable) experimental scale performance to (stable) field scale operation are combustion front temperature and combustion front velocity. Early stage results from the WHITESANDS THAI™ field pilot at Christina Lake, confirm high combustion zone temperatures (700-800°C), high fluids production of up to 2,000 barrels per day of gross fluids (50-55% bitumen cut) and signs of significant partial upgrading (up to 8.2°API). These measures of field pilot performance are consistent with the experimental findings from 3D physical experiments. They are very encouraging indicators for the future development of THAI™ on a commercial scale.