Method for CAGD recovery of heavy oil

Abstract

The invention provides a novel method of recovering oil by injecting oxygen into a chamber within an oil deposit thereby combusting oil at the chamber walls. The heated oil to drains towards the reservoir floor and is recovered oil via a production well.

1 . A method of recovering oil comprising:
 a) injecting oxygen into a chamber within an oil deposit thereby combusting oil at the chamber walls;   b) allowing heated oil to drain towards the reservoir floor; and   c) recovering oil via a production well.   
   
   
       2 . The method of  claim 1  wherein the chamber is a steam chamber. 
   
   
       3 . The method of  claim 2  wherein the combustion temperature at the chamber walls is above the saturated steam temperature at the steam chamber pressure. 
   
   
       4 . The method of  claim 2  wherein the combustion temperature is controlled by adjusting the oxygen concentration within the steam chamber. 
   
   
       5 . The method of  claim 1  wherein the oxygen is injected in admixture with steam. 
   
   
       6 . The method of  claim 5  wherein high purity oxygen is injected in admixture with steam. 
   
   
       7 . The method of  claim 1  wherein the chamber walls are maintained at a temperature above that at which the in place oil cracks. 
   
   
       8 . The method of  claim 5  wherein the combustion temperature is high enough to promote reaction of steam with carbonaceous materials. 
   
   
       9 . A method of producing upgraded oil from a heavy oil deposit comprising:
 a) injecting oxygen into a chamber within the deposit;   b) combusting fuel at the chamber walls;   c) maintaining the walls at a temperature above that at which the deposit oil cracks; and   d) withdrawing upgraded oil via a production well.   
   
   
       10 . The method of  claim 9  wherein the oxygen is injected in admixture with steam. 
   
   
       11 . The method of  claim 9  wherein the oxygen is injected in admixture with nitrogen. 
   
   
       12 . The method of  claim 1  wherein oxygen is supplied as air.