Autothermic Pyrolysis in-situ Conversion Technology and Pilot Test Project

Energy consumption and heating efficiency are key bottlenecks constraining the large-scale application of in-situ conversion technology. Autothermic pyrolysis in-situ conversion technology (ATS) proposes an innovative solution: by injecting oxidants such as ambient-temperature air into preheated shale formations, the exothermic oxidation reaction of residual carbon after the thermal cracking of kerogen is utilized to continuously generate substantial heat. This sustains the self-propagating thermal cracking process within the reservoir, significantly reducing the need for external energy supply. Laboratory experiments and numerical simulations show that, through precise control of process dynamics, the technology can achieve an energy efficiency of up to 14.80. With the auxiliary injection of a small amount of hydrocarbon gas, its applicability in shale formations with oil content below 5.0% can also be greatly enhanced.

To advance the engineering application of this technology, our team has developed a series of supporting key technologies, including efficient heating technology, shale complex fracture network construction technology, cross-scale multi-field coupling numerical simulation technology for thermal, fluid, solid, and chemical processes, underground space sealing technology, in-situ catalytic enhancement technology, and an integrated development system combining in-situ conversion, waste heat recovery, and CO₂ sequestration. This has established a comprehensive technological support system. Based on these technologies, our team has conducted two pilot tests in the Qingshankou Formation and Nenjiang Formation of the Songliao Basin in China, at formation depths of 80 meters and 480 meters, respectively. Both tests successfully extracted crude oil and natural gas, verifying the feasibility of this technological approach.

With the growing global demand for cleaner extraction of fossil energy resources, this technology can be widely applied in areas such as in-situ development of oil shale and low-to-moderate maturity shale oil, in-situ coal-to-oil and gasification, in-situ hydrogen production from crude oil, and high-temperature upgrading of heavy oil, demonstrating broad prospects for engineering applications.