Recovery of hydrocarbons by in situ thermal extraction
OwnerRobert P. Hendrickinventor
Life of this patent
Estimating the term…
Abstract
Hydrocarbons are recovered from a subterranean formation by providing a plurality of generally horizontal boreholes in the formation. The boreholes are vertically spaced across the thickness of the formation and extend from the top to the bottom thereof. Selected boreholes are heated by means of an external source to drive off hot hydrocarbon gases. The hot gases are fed to selected, unheated boreholes to effect a preheating of the selected boreholes and to cool the hot gases prior to their recovery from the formation.
Claims6
A method of producing hydrocarbons from a hydrocarbon-containing subterranean formation, comprising the steps of:
- a. providing a plurality of boreholes extending generally horizontally from a central dug access area into the hydrocarbon-containing formation, said boreholes being provided in vertically spaced relation from top to the bottom of the formation;
- b. selectively heating the boreholes adjacent the top of the formation to a first predetermined temperature which is sufficiently high to drive hydrocarbons from the formation in the form of hot gases;
- c. selectively establishing fluid communication between the boreholes adjacent the top of the formation and predetermined lower boreholes by external pipe or conduit access;
- d. passing said hot gases from the heated boreholes adjacent the top of the formation to said predetermined lower boreholes to effect heat exchange between said gases and the areas of the formation adjacent said predetermined lower boreholes, thus cooling said hot gases and preheating the areas of the formation adjacent said lower boreholes;
- e. serially heating to said first predetermined temperature successively lower boreholes relative to the top of the formation to drive hot hydrocarbon gases from the formation adjacent said successively lower boreholes, said predetermined temperature moving downwardly through the formation as successively lower boreholes are heated;
- f. serially and selectively establishing fluid communication between the successively heated lower boreholes and selected unheated boreholes to exchange heat from the generated hot hydrocarbon gases to the relatively cooler areas of the formation adjacent said unheated boreholes;
- g. continuing the serial heating of lower boreholes until all of said boreholes have been heated to said first predetermined temperature;
- and
- h. recovering the hydrocarbons driven from the formation by means of an in-situ heat exchange-refinery apparatus.
A method of producing hydrocarbons from a subterranean hydrocarbon-containing formation, which comprises the steps of:
- a. providing a substantially vertical central shaft extending into the hydrocarbon-containing formation, said shaft having a vertical axis;
- b. providing a plurality of boreholes extending into the formation in a generally radial direction relative to said vertical axis, said boreholes being provided in vertically spaced layers around the periphery of said central shaft, said vertically spaced layers extending downwardly from the top to the bottom of the formation;
- c. providing means for selectively heating said boreholes, said means being provided with energy from a source remote from said shaft and said boreholes;
- d. providing heat exchange means within said shaft said means including means for selectively establishing fluid communication between said boreholes;
- e. selectively energizing said heating means such that the temperature of the hydrocarbon containing formation adjacent the uppermost layer of boreholes is raised to a first predetermined temperature, sufficient to drive hydrocarbons from the heated formation in the form of hot gases;
- f. selectively establishing fluid communication between said uppermost layer of boreholes and predetermined lower boreholes to exchange heat from the hot hydrocarbon gases to the portions of the formation adjacent said predetermined lower boreholes and to partially cool said hot hydrocarbon gases;
- g. serially energizing the heating means to heat successively lower layers of said boreholes to said first predetermined temperature and to drive hot hydrocarbon gases from the adjacent formation, said temperature range moving downwardly through the formation as the heating means is energized to heat each successive lower layer of boreholes;
- h. serially and selectively establishing fluid communication between the successively heated layers of boreholes and selected unheated boreholes to exchange heat from the generated hot hydrocarbon gases to the relatively cooler areas of the formation adjacent said unheated boreholes;
- i. continuing the serial heating of lower layers of boreholes until all of said boreholes have been heated to said first predetermined temperature;
- and
- j. recovering the hydrocarbons driven from the formation.
Dependencies are inferred from the claim text.