In-situ kerogen conversion and recovery
AssigneeChevron U.S.A. Inc.
InventorsMarcus Oliver Wigand, Robert Martin Carlson, Mark Dean Looney
Life of this patent
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Abstract
Methods for extracting a kerogen-based product from subsurface (oil) shale formations. These methods rely on chemically modifying the shale-bound kerogen using a chemical oxidant so as to render it mobile. The oxidant is provided to a formation fluid in contact with the kerogen in the subsurface shale. An alkaline material is also provided to the formation fluid to mobilize organic acids which are produced during oxidation of the kerogen. A mobile kerogen-based product which includes the organic acids is withdrawn from the subsurface shale formation and further processed to isolate the organic acids contained therein.
Claims48
A process for extracting a kerogen-based product from a subsurface shale formation comprising subsurface shale, the process comprising the steps of:
- providing an oxidant to kerogen in subsurface shale;
- contacting the kerogen in the subsurface shale with the oxidant at a temperature in the range from 0° C. and 200° C. to form organic acids;
- and
- mobilizing at least a portion of the organic acids from the subsurface shale formation to produce a mobile kerogen-based product.
A process for extracting a kerogen-based product from a subsurface shale formation comprising subsurface shale, the process comprising the steps of:
- providing a reactive fluid, to kerogen in subsurface shale, the reactive fluid containing in the range from 0.1 wt. % to 40 wt. % of an oxidant, and having a pH in the range from 7 to 9;
- contacting the kerogen in the subsurface shale with the oxidant at a temperature in the range from 0° C. to 200° C. to form organic acids;
- and
- mobilizing at least a portion of the organic acids in a formation fluid having a pH in the range from 12 to 14 to produce a mobile kerogen-based product.
A process for extracting a kerogen-based product from a subsurface shale formation comprising subsurface shale, the process comprising the steps of:
- providing an oxidant to a fluid in a subsurface shale formation that contains kerogen, to produce a formation fluid;
- contacting the kerogen in the subsurface shale with the formation fluid at a temperature in the range of between 0° C. and 200° C. to form organic acids;
- providing an alkaline material to the formation fluid to form a mobile kerogen-based product comprising the organic acids;
- and
- recovering at least a portion of the mobile kerogen-based product from the subsurface shale formation.
Dependencies are inferred from the claim text.