In situ recovery from a hydrocarbon containing formation
An oil shale formation may be treated using an in situ thermal process. Heat may be applied to the formation to raise a temperature of a portion of the formation to a pyrolysis temperature. Heat input into the formation may be controlled to raise the temperature of portion at a selected rate during pyrolysis of hydrocarbons within the formation. A mixture of hydrocarbons, H 2 , and/or other formation fluids may be produced from the formation.
1. A method of treating a hydrocarbon containing formation in situ, comprising:
providing heat from one or more heat sources to at least a portion of the formation;
allowing the heat to transfer from the one or more heat sources to a selected section of the formation;
maintaining a pressure within at least a majority of the selected section of the formation to above 2.0 bar absolute; and
producing a mixture from the formation, wherein the produced mixture comprises a higher amount of non-condensable components as compared to non-condensable components producible from the formation under the same temperature conditions and at atmospheric pressure.
2. The method of claim 1 , wherein the one or more heat sources comprise at least two heat sources, and wherein superposition of heat from at least the two heat sources pyrolyzes at least some hydrocarbons within the selected section of the formation.
3. The method of claim 1 , wherein at least one of the heat sources comprises an electrical heater.
4. The method of claim 1 , wherein maintaining the pressure comprises controlling the pressure with a valve coupled to at least one of the heat sources.
5. The method of claim 1 , wherein maintaining the pressure comprises controlling the pressure with a valve coupled to a production well located in the formation.
6. The method of claim 1 , further comprising controlling formation conditions, wherein controlling formation conditions comprises maintaining a temperature in the selected section of the formation in a pyrolysis temperature range of about 270° C. to about 400° C.
7. The method of claim 1 , further comprising controlling a temperature in at least a majority of the selected section of the formation, wherein the pressure is controlled as a function of temperature, or the temperature is controlled as a function of pressure.
8. The method of claim 1 , wherein the non-condensable components comprise hydrogen gas, and wherein the hydrogen gas is greater than about 10% by volume of the total volume of the non-condensable components and wherein the hydrogen is less than about 80% by volume of the total volume of the non-condensable components.
9. The method of claim 1 , wherein about 0.1% by weight to about 15% by weight of the non-condensable components are olefins.
10. The method of claim 1 , wherein the non-condensable components comprise hydrogen (H 2 ) gas, and wherein a partial pressure of H 2 gas in the mixture is greater than about 0.5 bar.
11. A method of treating a hydrocarbon containing formation in situ, comprising:
providing heat from one or more heaters to at least a portion of the formation;
allowing the heat to transfer from at least one of the heaters to a selected section of the formation;
maintaining a pressure within at least a majority of the selected section of the formation to above 2.0 bar absolute; and
producing a mixture from the formation, wherein the produced mixture comprises a higher amount of non-condensable components as compared to non-condensable components producible from the formation under the same temperature conditions and at atmospheric pressure.
12. The method of claim 11 , wherein the one or more heaters comprise at least two heaters, and wherein superposition of heat from at least the two heat sources pyrolyzes at least some hydrocarbons within the selected section of the formation.
13. The method of claim 11 , wherein at least one of the heaters comprises an electrical heater.
14. The method of claim 11 , wherein controlling the pressure comprises controlling the pressure with a valve coupled to at least one of the heaters.
15. The method of claim 11 , wherein controlling the pressure comprises controlling the pressure with a valve coupled to a production well located in the formation.
16. The method of claim 11 , further comprising controlling formation conditions, wherein controlling formation conditions comprises maintaining a temperature in the part of the formation in a pyrolysis temperature range of about 270° C. to about 400° C.
17. The method of claim 11 , further comprising controlling a temperature in at least a majority of the part of the formation, wherein the pressure is controlled as a function of temperature, or the temperature is controlled as a function of pressure.
18. The method of claim 11 , wherein the non-condensable components comprise hydrogen gas, and wherein the hydrogen gas is greater than about 10% by volume of the total volume of the non-condensable components and wherein the hydrogen is less than about 80% by volume of the total volume of the non-condensable components.
19. The method of claim 11 , wherein about 0.1% by weight to about 15% by weight of the non-condensable components are olefins.
20. The method of claim 11 , wherein the non-condensable components comprise hydrogen (H 2 ) gas, and wherein a partial pressure of H 2 gas in the mixture is greater than about 0.5 bar.