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How does the internal-combustion method heat oil shale?
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oil shale
Kuskerite (oil shale) outcrop that dates to the Ordovician Period, northern Estonia.
The internal-combustion method for processing oil shale generates the necessary heat for pyrolysis by burning either a portion of the shale itself or available gases. This generated heat is then transferred to the ore through the circulation of hot gas.1
This approach is versatile and has been designed for use in both aboveground retorts and for in situ (underground) applications. Notable examples of technologies utilizing this method include the Kiviter process in Estonia, the Fushun process in China, and the Paraho Direct process in the United States.1