| CPC E21B 43/24 (2013.01) [C01B 3/12 (2013.01); C01B 3/36 (2013.01); C01B 3/38 (2013.01); E21B 43/168 (2013.01); E21B 36/00 (2013.01)] | 20 Claims |
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1. A method for treating a reservoir to recover a hydrogen-bearing gas, comprising:
providing a well passing through a surface of the earth into a reservoir of a formation;
in a pre-heat stage:
pre-heating the reservoir by injecting a heating fluid into the well; and
producing pre-production fluids from the reservoir to yield a depletion chamber within the reservoir;
in an injection stage:
injecting an oxygen-bearing gas via the well and the depletion chamber into the reservoir to yield an in-situ reactor zone where hydrocarbons including oil and gas are combusted to generate heat, steam, and carbon oxide gas components;
maintaining conditions for hydrogen-generating reactions, including one or more of gasification reactions, steam-reforming reactions, water-gas shift reactions, and aquathermolysis reactions to occur in the reservoir, thereby generating hydrogen; and
stopping injection of the oxygen-bearing gas;
in a soak stage:
shutting in the well; and
allowing remaining oxygen in the reservoir to be consumed and the hydrogen-generating reactions to continue, thereby continuing to generate hydrogen; and
in a production stage:
producing production fluids via the well to the surface including a hydrogen-bearing gas comprising the generated hydrogen;
continuing production through the well until a production rate of the hydrogen-bearing gas has dropped below a target rate; and
shutting in the well.
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