Rapid and accurate simulation of the In-situ Conversion Process using upscaled dynamic models

Abstract Numerical modeling of the In-situ Conversion Process (ICP) is a challenging endeavor involving non-isothermal multiphase flow, compositional PVT behavior, and chemical reactions that convert solid kerogen into light hydrocarbons and are tightly coupled to the temperature propagation. The objective of the reported work is to significantly accelerate the ICP simulations using fast upscaled dynamic models that deliver good prediction accuracy. We take advantage of the fluid- and heat-flow based local transmissibility upscaling techniques. A fully automatic scale-up workflow is scripted for pattern-scale ICP models, which generates upscaled models that are, in turn, simulated using a proprietary simulator. We demonstrate the consistency, accuracy, and efficiency of the upscaling workflow using a realistic pattern-scale ICP model. A simple yet effective upscaling workflow is developed for the fast and accurate simulation of ICP using a novel integrated upscaling and flow simulation platform. Overall, the upscaling workflow is simple, generic, and delivers computational speed-up while retaining a reasonable level of fine-scale model accuracy. Upscaled models lead to more robust simulations of ICP from the numerical perspective as evidenced by main numerical performance indicators. The upscaling script is implemented as part of an easily customizable ICP simulation deck. It is used for simulation-intensive ICP performance forecasting workflows (e.g., optimization, uncertainty quantification, and history matching) targeting oil-shale resources worldwide.