Junggar

The Junggar Basin CO₂-EOR projects are located in Xinjiang, northwest China, within the Junggar Basin, one of China’s major onshore petroleum provinces. Operated primarily by CNPC/PetroChina, these projects involve tertiary recovery through CO₂ injection into mature oil reservoirs following primary production and waterflood development. Target reservoirs consist mainly of Permian to Jurassic sandstone formations deposited in fluvial and lacustrine environments, characterized by heterogeneous permeability and stratigraphic trapping typical of foreland basin settings. CO₂ injection is designed to improve recovery efficiency through miscible or near-miscible displacement, enhancing oil mobility via viscosity reduction, swelling, and interfacial tension effects. Injection operations typically use pattern flood configurations with water-alternating-gas (WAG) cycles to control mobility and improve sweep efficiency. CO₂ sources include nearby industrial facilities and natural gas processing streams, with produced CO₂ separated and recycled through compression infrastructure. Retained volumes contribute to geologic storage through structural trapping, residual trapping, and dissolution mechanisms. The Junggar CO₂-EOR developments form part of China’s broader CCUS strategy, demonstrating integrated utilization of industrial CO₂ streams for enhanced recovery while evaluating long-term storage performance in deep onshore sandstone reservoirs.