Dynamic optimization control of injection-production parameters for autothermic pyrolysis in-situ conversion process of oil shale
Abstract
Autothermic pyrolysis in-situ conversion process in oil shale has emerged as a significant development direction due to its environmental friendliness and cost advantages. However, conventional constant injection-production parameters often lead to inefficient compression energy input and formation oxidation losses, limiting further improvement in energy efficiency and oil yield. This study establishes a dynamic optimization model for injection-production parameters in oil shale autothermic pyrolysis in-situ extraction and develops a method for dynamically regulating gas injection rate and oxygen content to enhance process economy and feasibility. Results indicate that under the optimal gas injection parameters (adjustment time: day 120, decay rate: 1200 m³/d², terminal flow rate: 40 m³/day), the steady-state phase in late production reduces compression energy consumption by 90% and CO₂ production by 48%, significantly decreasing cumulative compression energy input and suppressing hydrocarbon oxidation losses. Consequently, the energy efficiency peak reaches 13.87, representing a 132.33% improvement over constant-rate injection, while oil production increases to 47 m³/m, a 66.9% enhancement. Furthermore, synergistic regulation of oxygen content and injection rate reduces compression energy by an additional 16%, elevating the energy efficiency peak to 14.80—a 6.71% further increase—demonstrating technical feasibility for industrial application. These findings and key parameters provide theoretical and technical support for the large-scale implementation of autothermic pyrolysis in-situ conversion process in oil shale.
Document Type: Original article
Cited as: Zhu, C., He, C., Wu, J., Guo, W. Dynamic optimization control of injection-production parameters for autothermic pyrolysis in-situ conversion process of oil shale. Advances in Geo-Energy Research, 2026, 20(1): xxx-xxx. https://doi.org/10.46690/ager.2026.05.03
DOI:
https://doi.org/10.46690/ager.2026.05.03Keywords:
Oil shale; autothermic pyrolysis in-situ conversion process, injection-production parameters, numerical simulation, dynamic regulationReferences
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Copyright (c) 2026 Chaofan Zhu, Cheng He, Jiyue Wu, Wei Guo
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