Converting Oil Shale to Liquid Fuels with the Alberta Taciuk Processor: Energy Inputs and Greenhouse Gas Emissions

Abstract

We calculate the greenhouse gas (GHG) emissions from producing liquid fuels from Green River oil shale with the Alberta Taciuk Processor (ATP). Kerogen contained in oil shale can be retorted to produce liquid and gaseous hydrocarbons. The ATP is an above-ground oil shale retort that combusts the coke or “char” deposited on the shale during retorting to fuel the retorting process. Using life cycle assessment (LCA), we calculate the energy inputs and outputs of each process stage. We then calculate the resulting full-fuel-cycle GHG emissions from producing reformulated gasoline using the ATP. Full-fuel-cycle GHG emissions are conservatively calculated at ≈130−150 g CO₂ equiv/MJ of gasoline produced. These emissions are 1.5 to 1.75 times larger than emissions from conventionally produced gasoline. The results depend most sensitively on the grade of shale used and the rate of carbonate mineral decomposition, which causes inorganic carbon dioxide (CO₂) release.