Apparatus, system, and method for in-situ extraction of hydrocarbons

A system for extracting hydrocarbons in-situ, the system comprising:

• at least one well drilled through a hydrocarbon bearing formation, the hydrocarbon bearing formation comprising a hydrocarbon;
• a completion unit configured to position an injection tube near a fluid injection point disposed within a target zone and to position a production tube near a fluid production point disposed within the target zone;
• a heat source configured to heat a thermal conduit fluid to a temperature selected to pyrolyze the hydrocarbon;
• an injection unit that heats the target zone by circulating the thermal conduit fluid through the target zone, the thermal conduit fluid sweeping a hydrogen rich product of the pyrolyzation reaction into the production tube leaving a hydrogen poor product of the pyrolyzation reaction in the target zone;
• a combustion unit configured to inject a oxygen mixture into the target zone and combust the hydrogen poor product to heat the oxygen mixture;
• and
• a cooling unit configured to pump a cool gas stream into the target zone to absorb residual heat from the target zone;
• a recycling unit configured to recycle the heat absorbed by the cool gas stream to heat an adjacent well;
• and
• an abandonment unit that injects a solution of sodium bentonite and water under high pressure into the target zone, sealing the depleted hydrocarbon formation with the sodium bentonite and water solution to prevent intrusion and contamination of groundwater in the target zone.

An apparatus for extracting hydrocarbons in-situ, the apparatus comprising:

• a completion unit configured to position an injection tube near a fluid injection point substantially at the bottom of a target zone of an oil shale formation and to position a production tube near a fluid production point substantially at the top of the target zone, the injection tube comprising concentric coiled tube with an insulating region disposed between an inner tube and an outer tube, wherein an inner diameter of the inner tube is between about 1 inch and about 2 inches;
• a heat source configured to heat the thermal conduit fluid to a temperature selected to pyrolyze a hydrocarbon;
• an injection unit that heats the target zone by circulating the thermal conduit fluid through the target zone, the thermal conduit fluid sweeping a hydrogen rich product of the pyrolyzation reaction into the production tube leaving a hydrogen poor product of the pyrolyzation reaction in the target zone;
• and
• a combustion unit configured to inject a combustion mixture into the target zone to combust the hydrogen poor product to heat the air.

A method for extracting hydrocarbons, the method comprising:

• performing a first stage extraction on a target zone of an hydrocarbon formation by:
• positioning an injection tube within a well, the injection tubing disposed substantially at a top of the target zone;
• positioning a production tube within a well, the production tube disposed substantially at a bottom of the target zone;
• heating a thermal conduit fluid;
• injecting the thermal conduit fluid into the target zone such that the heated thermal conduit fluid entrains in-situ hydrocarbons to generate a production fluid;
• and
• producing the production fluid