Unveiling Success From Cyclic Steam Injections for Heavy Oil Recovery in India and the Orinoco Oil Belt

Abstract This study highlights the successful implementation of the cyclic steam injection process in a heavy oil field in India and in numerical reservoir simulation studies in the Orinoco Oil Belt. It focuses on optimizing key variables such as steam quality, reservoir energy transfer, well-productivity enhancement, and environmental impact. The methodology incorporates an innovative, comprehensive high-quality steam generation system, producing steam qualities ranging from 95% to 99%. In the Orinoco Oil Belt, the efficiency of injecting high-quality steam was evaluated within an extra-heavy oil formation situated at a depth of 3010 feet and under a pressure of 1100 psi. Numerical results from the Orinoco Oil Belt demonstrate a substantial impact of high-quality steam, achieving a 400% increase in oil extraction rates and an additional 28% increase in accumulated oil compared to conventional methods. This innovative system requires 8% less fuel for equivalent energy generation and leads to a 7.7% reduction in non-condensable gas production. These findings served as the foundation for designing a cyclic steam stimulation (CSS) pilot test in India. In preparation for the pilot test in India, a meticulously designed steam generation system with superheaters and cyclone separators was developed. This system demonstrates its capability by generating steam with qualities ranging from 95% to 99%, utilizing LPG as fuel. Facing challenges such as average reservoir depths of 3700 feet, low permeabilities (1000-2000 mD), oil viscosity of 20000 cP@140°F, and a pressure of 1650 psi, the execution of cyclic thermal stimulation involved 7 wells subjected to injection pressures between 1500 and 2100 psi, and temperatures of 300°C, maintaining steam flow rates from 3.0 to 4.0 tons per hour. Following thermal stimulation, oil production rates showed an overwhelmingly positive outcome with an average increase of 420%. The innovations and best practices presented in this study will facilitate the adoption of efficient thermal processes, ensuring a higher recovery factor, reduced water, and fuel consumption, and minimizing environmental impact. Operationally, non-productive periods were reduced to less than 2%, achieving steam generation with a quality exceeding 90%.