Recovery From A Hydrocarbon Reservoir

Abstract

Embodiments described herein provide systems and methods for improving production of hydrocarbon resources. A method for improving recovery from a subsurface hydrocarbon reservoir includes generating a productivity map for a plurality of wells in a contiguous region of a reservoir and injecting different mixtures of non-condensable gas (NCG) and steam into at least two injection wells in the plurality of wells based, at least in part, on the productivity map.

What is claimed is: 
     
         1 . A method for improving recovery from a subsurface hydrocarbon reservoir, comprising:
 generating a productivity map for a plurality of wells in a contiguous region of a reservoir; and   injecting different mixtures of non-condensable gas (NCG) and steam into at least two injection wells in the plurality of wells based, at least in part, on the productivity map.   
     
     
         2 . The method of  claim 1 , comprising injecting mixtures that range in composition from completely NCG to completely steam. 
     
     
         3 . The method of  claim 1 , comprising injecting mixtures that are substantially NCG into injection wells in less productive regions of the reservoir. 
     
     
         4 . The method of  claim 1 , comprising injecting mixtures that are substantially steam into injection wells in more productive regions of the reservoir. 
     
     
         5 . The method of  claim 1 , comprising, if steam production decreases:
 injecting steam into injection wells in highly productive regions; and   injecting NCG, NCG and steam mixtures, or both, into injection wells in less productive regions.   
     
     
         6 . The method of  claim 1 , comprising, if steam demand increases:
 injecting steam into injection wells in highly productive regions; and   injecting NCG, NCG and steam mixtures, or both, into injection wells in less productive regions.   
     
     
         7 . The method of  claim 1 , comprising:
 injecting a solvent into a series of injection wells to increase the production of hydrocarbons from the reservoir; and   injecting a NCG comprising a hydrocarbon in a sequential manner in the series of injection wells to push the solvent to a production well.   
     
     
         8 . The method of  claim 7 , comprising:
 injecting a low value NCG in a sequential manner in the series of injection wells to push the NCG comprising a hydrocarbon to a production well.   
     
     
         9 . The method of  claim 1 , comprising:
 injecting a mixture substantially comprising a NCG into a plurality of injection wells located along the edge of a reservoir; and   injecting a mixture substantially comprising steam into a plurality of injection wells located in a center region of a reservoir.   
     
     
         10 . The method of  claim 1 , comprising injecting different mixtures of NCG and steam into two wells drilled from a single pad. 
     
     
         11 . The method of  claim 1 , comprising injecting different mixtures of NCG and steam into wells drilled from adjacent pads. 
     
     
         12 . A system for improving the recovery of resources from a reservoir, comprising:
 a reservoir; and   a plurality of injection wells drilled through the reservoir, wherein at least two different injection wells in the plurality of injection wells are configured to inject different mixtures of non-condensable gas (NCG) and steam.   
     
     
         13 . The system of  claim 12 , wherein at least two different injection wells in the plurality of injection wells are drilled from a single pad. 
     
     
         14 . The system of  claim 12 , comprising a plurality of production wells, wherein each production well is associated with an injection well in the plurality of injection wells. 
     
     
         15 . The system of  claim 12 , comprising a plurality of pads, wherein each pad has a plurality of steam assisted gravity drainage (SAGD) well pairs. 
     
     
         16 . The system of  claim 12 , comprising a productivity map created by mapping the steam-to-oil rates for each of a plurality of production wells. 
     
     
         17 . The system of  claim 16 , comprising an injection well associated with a low productivity production well, wherein the injection well is configured to inject either steam or a NCG. 
     
     
         18 . A method for harvesting hydrocarbons from an oil sands reservoir, comprising:
 drilling a plurality of steam assisted gravity drainage (SAGD) well pairs through the oil sands reservoir;   generating a map of the productivity of each of the plurality of SAGD well pairs;   injecting a mixture comprising steam into a well pair with a high productivity; and   injecting a mixture comprising a non-condensable gas into a well pair with a low productivity.   
     
     
         19 . The method of  claim 18 , comprising injecting a mixture comprising a non-condensable gas into a well pair at an edge of a reservoir. 
     
     
         20 . The method of  claim 18 , comprising injecting a mixture comprising steam into a well pair proximate to the center of the reservoir.