Thermal hydrocarbon recovery method with non-condensable gas injection

Abstract

A method for recovering subsurface hydrocarbons, including heavy oil or bitumen, wherein a heated non-condensable gas such as nitrogen is injected downhole to heat the reservoir, followed by a steam injection step to heat the hydrocarbon to enable its flow to the wellbore and production to surface. The dual injection method can be repeated as desired to enhance production of the hydrocarbon resource, and in the case of cyclic steam stimulation would involve a period of shutting in the well after injection of the non-condensable gas and steam prior to the production phase.

1 . A method for recovering a hydrocarbon from a reservoir, the method comprising the steps of:
 a. drilling at least one well from surface to the reservoir;   b. heating a volume of non-condensable gas to a target temperature;   c. injecting the non-condensable gas down the at least one well to the reservoir;   d. allowing the non-condensable gas to heat the reservoir and the hydrocarbon;   e. injecting steam down the at least one well to the reservoir;   f. allowing the steam to heat the reservoir and the hydrocarbon; and   g. producing a portion of the hydrocarbon to the surface.   
     
     
         2 . The method of  claim 1  wherein the hydrocarbon is a heavy hydrocarbon. 
     
     
         3 . The method of  claim 2  wherein the heavy hydrocarbon is heavy crude oil or bitumen. 
     
     
         4 . The method of  claim 1  wherein the reservoir is composed primarily of carbonate material. 
     
     
         5 . The method of  claim 1  wherein the reservoir is composed primarily of non-carbonate clastic material. 
     
     
         6 . The method of  claim 1  wherein the reservoir includes fractures. 
     
     
         7 . The method of  claim 6  wherein the fractures are naturally occurring. 
     
     
         8 . The method of  claim 1  wherein the at least one well is a single well used for both injection and production. 
     
     
         9 . The method of  claim 1  wherein the at least one well is at least two wells, at least one of which is an injector well and at least one of which is a producer well. 
     
     
         10 . The method of  claim 1  wherein the non-condensable gas is selected from the group consisting of nitrogen, air, methane and carbon dioxide. 
     
     
         11 . The method of  claim 1  wherein the target temperature is in the range of 100 to 400 degrees Celsius. 
     
     
         12 . The method of  claim 1  wherein the non-condensable gas and the steam are injected through separate wells. 
     
     
         13 . The method of  claim 1  further comprising repeating steps b. through g. as desired. 
     
     
         14 . A method for recovering a hydrocarbon from a reservoir having at least one injector well therein, the method comprising the steps of:
 a. injecting a heated non-condensable gas down the at least one injector well to the reservoir;   b. injecting steam down the at least one injector well to the reservoir;   c. producing a portion of the hydrocarbon to the surface; and   d. repeating steps a. through c. as desired.   
     
     
         15 . The method of  claim 14  wherein the hydrocarbon is a heavy hydrocarbon. 
     
     
         16 . The method of  claim 15  wherein the heavy hydrocarbon is heavy crude oil or bitumen. 
     
     
         17 . The method of  claim 14  wherein the reservoir is composed primarily of carbonate material. 
     
     
         18 . The method of  claim 14  wherein the reservoir is composed primarily of non-carbonate clastic material. 
     
     
         19 . The method of  claim 14  wherein the reservoir includes fractures. 
     
     
         20 . The method of  claim 19  wherein the fractures are naturally occurring. 
     
     
         21 . The method of  claim 14  wherein the at least one injector well is a single well used for both injection and production. 
     
     
         22 . The method of  claim 14  wherein the at least one injector well is at least two injector wells, at least one of which is also configured for use as a producer well. 
     
     
         23 . The method of  claim 14  wherein the non-condensable gas is selected from the group consisting of nitrogen, air, methane and carbon dioxide. 
     
     
         24 . A method for recovering a hydrocarbon from a reservoir, the method comprising the steps of:
 a. drilling at least one well from surface to the reservoir;   b. heating a volume of non-condensable gas to a target temperature;   c. injecting the non-condensable gas down the at least one well to the reservoir at a desired volume per unit time and for a desired period of time;   d. ceasing injecting of the non-condensable gas and allowing the injected non-condensable gas to heat the reservoir and the hydrocarbon;   e. injecting steam down the at least one well to the reservoir;   f. ceasing injection of the steam and allowing the steam to heat the reservoir and the hydrocarbon; and   g. producing a portion of the hydrocarbon to the surface.   
     
     
         25 . The method of  claim 24  wherein the hydrocarbon is a heavy hydrocarbon. 
     
     
         26 . The method of  claim 25  wherein the heavy hydrocarbon is heavy crude oil or bitumen. 
     
     
         27 . The method of  claim 24  wherein the reservoir is composed primarily of carbonate material. 
     
     
         28 . The method of  claim 24  wherein the reservoir is composed primarily of non-carbonate clastic material. 
     
     
         29 . The method of  claim 24  wherein the reservoir includes fractures. 
     
     
         30 . The method of  claim 29  wherein the fractures are naturally occurring. 
     
     
         31 . The method of  claim 24  wherein the at least one well is a single well used for both injection and production. 
     
     
         32 . The method of  claim 24  wherein the at least one well is at least two wells, at least one of which is an injector well and at least one of which is a producer well. 
     
     
         33 . The method of  claim 24  wherein the non-condensable gas is selected from the group consisting of nitrogen, air, methane and carbon dioxide. 
     
     
         34 . The method of  claim 24  wherein the target temperature is in the range of 100 to 400 degrees Celsius. 
     
     
         35 . The method of  claim 24  wherein the non-condensable gas and the steam are injected through separate wells. 
     
     
         36 . The method of  claim 24  wherein the desired volume per unit time for the non-condensable gas injection is in the range of 20 to 100 mmcfd. 
     
     
         37 . The method of  claim 24  further comprising repeating steps b. through g. as desired. 
     
     
         38 . A method for building a steam chamber in a fractured subsurface hydrocarbon reservoir having at least one injector well therein, the method comprising the steps of:
 a. heating a volume of non-condensable gas to a target temperature;   b. injecting the non-condensable gas down the at least one injector well to the reservoir;   c. allowing the injected non-condensable gas to heat the reservoir and hydrocarbon in the reservoir;   d. injecting steam down the at least one injector well to the reservoir;   e. shutting in the at least one injector well and allowing the injected steam to heat the reservoir and the hydrocarbon in the reservoir; and   f. producing a portion of the hydrocarbon to the surface.   
     
     
         39 . The method of  claim 38  comprising the further steps of shutting in the at least one injector well after injecting the non-condensable gas, and subsequently opening the at least one injector well before injecting the steam. 
     
     
         40 . The method of  claim 38  wherein the hydrocarbon is a heavy hydrocarbon. 
     
     
         41 . The method of  claim 40  wherein the heavy hydrocarbon is heavy crude oil or bitumen. 
     
     
         42 . The method of  claim 38  wherein the reservoir is composed primarily of carbonate material. 
     
     
         43 . The method of  claim 38  wherein the reservoir is composed primarily of non-carbonate clastic material. 
     
     
         44 . The method of  claim 38  wherein fractures in the reservoir are naturally occurring. 
     
     
         45 . The method of  claim 38  wherein the at least one injector well is a single well used for both injection and production. 
     
     
         46 . The method of  claim 38  wherein the at least one injector well is at least two injector wells, at least one of which is also configured for use as a producer well. 
     
     
         47 . The method of  claim 38  wherein the non-condensable gas is selected from the group consisting of nitrogen, air, methane and carbon dioxide. 
     
     
         48 . The method of  claim 38  wherein the target temperature is in the range of 100 to 400 degrees Celsius. 
     
     
         49 . The method of  claim 38  wherein the non-condensable gas and the steam are injected through separate wells. 
     
     
         50 . The method of  claim 38  further comprising repeating steps a. through f. as desired.