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

Abstract

An apparatus, system, and method are disclosed for in-situ extraction of hydrocarbons from a hydrocarbon bearing formation. The system includes a well drilled through a hydrocarbon bearing formation, and a completion unit that places an injection tube near a fluid injection of a target zone and a production tube near a fluid production point of the target zone. The injection tube comprising a tube with an inner diameter between about 1 inch and about 2 inches. The system includes a heat source, and a thermal conduit fluid that delivers heat from the heat source to the target zone. A mixer mixes an oxygen mixture and an injection unit injects the oxygen mixture into the depleted target zone to combust a coke remainder within the target zone. The system further includes a recycling unit configured to circulate a cool gas through the heated target zone to absorb the thermal energy disposed in the heated target zone.

1 . A method for extracting oil from a hydrocarbon bearing formation, the method comprising:
 performing a first stage extraction on a target zone of a hydrocarbon bearing formation by:
 positioning an injection tube within a well; 
 positioning a production tube within a well; 
 heating a thermal conduit fluid; 
 injecting the thermal conduit fluid into the target zone such that the heated thermal conduit fluid entrains in-situ kerogen to generate a production fluid; and 
 producing the production fluid; 
   performing a heat recycling stage on the target zone by:
 recycling the heat contained within the target zone by pumping a cool gas stream into the target zone, the cool gas stream absorbing heat from the hydrocarbon bearing formation; and 
 extracting the heated cool gas stream. 
   
   
   
       2 . The method of  claim 1 , further comprising performing a formation heating stage on the target zone by:
 injecting an oxygen mixture into the target zone; and   combusting a coke remainder in the target zone to add thermal energy to the oxygen mixture.   
   
   
       3 . The method of  claim 2 , further comprising;
 extracting the heated oxygen mixture through the production tube, the heated oxygen mixture comprising a carbon dioxide product of the coke combustion;   passing the heated oxygen mixture through a heat exchanger, the heat exchanger configure to heat a second thermal conduit fluid for a first stage extraction of an adjacent well.   
   
   
       4 . The method of  claim 2 , wherein oxygen mixture comprises a thermal conduit fluid mixed with oxygen, the method further comprising injecting the heated oxygen mixture into an adjacent well and performing a first stage extraction on the adjacent well. 
   
   
       5 . The method of  claim 3 , further comprising injecting the second thermal conduit fluid into a second target zone and performing a first stage extraction on the second target zone. 
   
   
       6 . The method of  claim 1 , wherein the production fluid comprises liquid hydrocarbons and hydrocarbon vapor and wherein the thermal conduit fluid comprises a mixture of natural gas and water in the form of steam. 
   
   
       7 . The method of  claim 2 , wherein the formation heating stage is performed after the kerogen has been substantially removed from the target zone, the method further comprising sealing the well such that substantially no oxygen enters the target zone during the first stage extraction to prevent increased acidity of the production fluid. 
   
   
       8 . The method of  claim 1 , further comprising heating the target zone with the thermal conduit fluid, the target zone heated to a temperature between about 300 degrees Celsius and about 400 degrees Celsius during the first stage extraction. 
   
   
       9 . The method of  claim 1 , wherein injecting the thermal conduit fluid comprises passing the thermal conduit fluid through an injection tube having a diameter proportioned to increase velocity and reduce the residence time of the thermal conduit fluid within the injection tube, wherein the diameter of the tube is between about 1 inch and about 2 inches, and wherein the injection tube and the production tube are both positioned within a vertically oriented well. 
   
   
       10 . The method of  claim 1 , wherein injecting the thermal conduit fluid comprises passing the thermal conduit fluid through an injection tube comprising an insulation region disposed between an inner tube and an outer tube, wherein the inner diameter of the inner tube is between about 1 inch and about 2 inches. 
   
   
       11 . The method of  claim 1 , wherein injecting the thermal conduit fluid comprises passing the thermal conduit fluid through an injection tube comprising an insulation region disposed between an inner tube and an outer tube, wherein the inner diameter of the inner tube is between about 1 inch and about 1.66 inches. 
   
   
       12 . The method of  claim 1 , further comprising controlling the percentage of oxygen during the formation heating stage to maintain a combustion temperature below about 500 degrees Celsius within the target zone. 
   
   
       13 . The method of  claim 1 , further comprising exchanging heat from the cool gas stream exiting the well with a thermal conduit fluid of an adjacent well. 
   
   
       14 . The method of  claim 1 , further comprising performing a well abandonment stage on the target zone by injecting a solution of sodium bentonite and water under high pressure into the target zone, sealing the depleted oil shale with the sodium bentonite and water to prevent intrusion and contamination of groundwater in the target zone. 
   
   
       15 . The method of  claim 14 , further comprising adjusting the viscosity of the sodium bentonite and water solution such that the sodium bentonite and water solution fully expands within the target zone. 
   
   
       16 . 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.   
   
   
       17 . The system of  claim 16 , wherein the heat source comprises an oxygen mixture N heated by a combustion unit in an adjacent well. 
   
   
       18 . The system of  claim 16 , further comprising a heat exchanger configured to transfer heat from the heat source to the thermal conduit fluid without mixing the heat source with the thermal conduit fluid. 
   
   
       19 . The system of  claim 16 , further comprising an mixer configured to mix an oxygen fraction and an air fraction to create the oxygen mixture, wherein the oxygen fraction comprises an oxygen flow, wherein the air fraction comprises an air flow and air composition, the system further comprising an air-oxygen module configured to modulate the air flow and the oxygen flow based on a heat requirement and air composition. 
   
   
       20 . The system of  claim 19 , wherein the air-oxygen module is further configured to maintain a combustion temperature under about 500 degrees Celsius. 
   
   
       21 . The system of  claim 16 , wherein the heat source is configured to heat the thermal conduit fluid to a temperature between about 300 degrees Celsius and about 400 degrees Celsius and wherein the combustion unit is configured to combust the hydrogen poor product after substantially the entire hydrogen rich product of the pyrolyzation reaction is swept into the production tube. 
   
   
       22 . The system of  claim 16 , wherein the injection tube comprises an insulation 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 1.66 inches. 
   
   
       23 . 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.   
   
   
       24 . The apparatus of  claim 23 , further comprising a cooling unit and a recycling unit, the cooling unit configured to pump a cool gas stream into the target zone to absorb heat from the hydrocarbon bearing formation, the recycling unit configured to recycle the heat absorbed by the cool gas stream to heat an adjacent well. 
   
   
       25 . 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