Electric and fired steam generation systems

Abstract

Methods and systems relate to steam assisted oil recovery utilizing a fired boiler and an electric boiler, which may be disposed closer to an injection well than the fired boiler. A gas turbine produces electricity supplied to the electric boiler and flue gas exhaust that may input into the fired boiler. The electric boiler may vaporize condensate that forms from the steam generated in the fired boiler prior to being introduced into the injection well.

1 . A method of steam assisted oil recovery with dual steam generation, comprising:
 producing electricity with an onsite gas turbine;   generating steam with a fired boiler at a first location;   conveying the steam to a second location resulting in a mixture formed of the steam and condensate caused by heat loss during the conveying;   separating the steam from the condensate in the mixture;   heating the condensate in an electric boiler powered by the electricity from the gas turbine to convert the condensate back to a vapor phase combined with the steam separated from the condensate to provide a combined steam flow; and   introducing the combined steam flow into a formation for the steam assisted oil recovery.   
     
     
         2 . The method according to  claim 1 , wherein the fired boiler is coupled to use a flue gas exhaust of the gas turbine as an oxidant feed for combustion in the fired boiler. 
     
     
         3 . The method according to  claim 1 , further comprising capturing carbon dioxide from a flue gas exhaust of the fired boiler. 
     
     
         4 . The method according to  claim 1 , wherein the fired boiler is coupled to use a flue gas exhaust of the gas turbine as an oxidant feed for combustion in the fired boiler and carbon dioxide is captured from combustion products of the fired boiler. 
     
     
         5 . The method according to  claim 1 , wherein the electric boiler is disposed within 100 meters of where the combined steam flow is introduced into a well and the fired boiler is located further than 100 meters from the well. 
     
     
         6 . The method according to  claim 1 , wherein the fired boiler is a once through steam generator. 
     
     
         7 . The method according to  claim 1 , wherein the condensate enters the electric boiler at a temperature of at least 300° C. 
     
     
         8 . The method according to  claim 1 , wherein the fired boiler at the first location is at least 0.5 kilometers from the second location and the electric boiler. 
     
     
         9 . The method according to  claim 1 , wherein the fired boiler alone supplies steam requirements for one or more well pads forming a proximal pad set closer to the fired boiler than one or more well pads forming a distal pad set that includes the electric boiler. 
     
     
         10 . The method according to  claim 1 , wherein the steam assisted oil recovery is a steam assisted gravity drainage process. 
     
     
         11 . A method of steam assisted oil recovery with dual steam generation, comprising:
 producing electricity with an onsite gas turbine;   generating steam with both a fired boiler coupled to use a flue gas exhaust of the gas turbine as an oxidant feed for combustion in the fired boiler and an electric boiler powered by the electricity from the gas turbine; and   introducing the steam from the fired boiler and the electric boiler into at least one injection well for the steam assisted oil recovery.   
     
     
         12 . The method according to  claim 11 , wherein the fired boiler alone supplies steam requirements for one or more well pads forming a proximal pad set closer to the fired boiler than one or more well pads forming a distal pad set that includes the electric boiler. 
     
     
         13 . The method according to  claim 11 , wherein the fired boiler is at least 0.5 kilometers from the electric boiler. 
     
     
         14 . A system for steam assisted oil recovery with dual steam generation, comprising:
 an onsite gas turbine to produce electricity;   a fired boiler to generate steam at a first location;   a steam conduit coupled to the fired boiler for conveying the steam to a second location;   a separator coupled to the steam conduit for dividing the steam from condensate formed by heat loss along the steam conduit;   an electric boiler powered by the electricity from the gas turbine to heat and convert the condensate back to a vapor phase; and   an injection well coupled to vapor outputs from the separator and the electric boiler for the steam assisted oil recovery.   
     
     
         15 . The system according to  claim 14 , wherein the fired boiler is coupled to use a flue gas exhaust of the gas turbine as an oxidant feed for combustion in the fired boiler. 
     
     
         16 . The system according to  claim 14 , further comprising a recovery unit to capture carbon dioxide from a flue gas exhaust of the fired boiler. 
     
     
         17 . The system according to  claim 14 , wherein the fired boiler is coupled to use a flue gas exhaust of the gas turbine as an oxidant feed for combustion in the fired boiler and carbon dioxide is captured from combustion products of the fired boiler. 
     
     
         18 . The system according to  claim 14 , wherein the electric boiler is disposed within 100 meters of the injection well and the fired boiler is located further than 100 meters from the injection well. 
     
     
         19 . The system according to  claim 14 , wherein the fired boiler is a once through steam generator. 
     
     
         20 . The system according to  claim 14 , wherein the fired boiler at the first location is at least 0.5 kilometers from the second location and the electric boiler.