摘要 |
A method for recovering liquid and gaseous products from an in situ oil shale retort in a subterranean formation containing oil shale is disclosed. The method is practiced on an in situ oil shale retort having a plurality of fragmented permeable masses of formation particles with an upper and at least one lower fragmented mass. A zone of unfragmented formation intervenes between such fragmented masses and has a plurality of vertically extending holes for distributing fluid from the fragmented mass above to the fragmented mass below the zone of unfragmented formation. A processing gas is introduced to the upper fragmented mass and an off gas is withdrawn from the lower fragmented mass establishing a retorting zone in the upper fragmented mass and advancing the retorting zone downwardly through the upper fragmented mass, through such holes in the zone of unfragmented formation, and into and through the lower fragmented mass. The oil shale within the fragmented masses is retorted producing liquid and gaseous products. The liquid products are recovered from the fragmented mass from which they are produced and the gaseous products are recovered from the off gas withdrawn from the lower fragmented mass.
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