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[摘要]：In situ processing methods for producing oil from oil shale have certain advantages over mining and surface processing. Land surface disturbance is minimal, mining operations are avoided, and deep or other resources inaccessible to mining can be utilized. In situ thermal processing technologies have greatly advanced recently, and include cyclic steam injection, steam assisted gravity drainage, in situ combustion, underground gasification, in situ pyrolysis, and so on. Each technology has advantages and disadvantages depending on economic, environmental, geological, and physical characteristics of the application. It may be beneficial to combine different processes, where possible, to improve efficiency and recovery. The pyrolysis process in which kerogen is converted to oil, gas, and coke is energy intensive. We show how the energy requirement can be reduced significantly by following a period of pyrolysis with in situ coke combustion. The total energy reduction is dependent on the time at which the combustion operations are begun relative to the start of the pyrolysis process. Carbon dioxide emissions for different technologies will also be a concern for potential oil shale processing development as eminent constraints add risks to these opportunities. The potential for carbon dioxide recycling and storage back into the reservoir was also explored, and it is shown that the CO2 stored by reinjection is insignificant when compared to CO2 generation from the overall process. There is an apparent trade-off between input energy savings and CO2 emissions in this process. |
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