Steam generator and carbon dioxide capture

Abstract

Methods and systems generate steam for injection into a formation in order to facilitate oil recovery and also capture carbon dioxide in a recovery unit that receives flue gas exhaust from such steam generation. The methods and systems integrate various process streams from and to the carbon dioxide recovery unit. Such integration provides resulting benefits associated with efficiency and/or carbon dioxide avoidance.

1 . A method of steam assisted oil recovery integrated with carbon dioxide capture, comprising:
 feeding water to a steam generator that produces injection steam and liquid blowdown separated from the injection steam at a first pressure;   introducing the injection steam into a formation for the steam assisted oil recovery;   flashing the blowdown at a second pressure lower than the first pressure to provide regenerator steam and condensate;   passing the condensate through a heat exchanger to preheat the water prior to the water entering the steam generator; and   supplying the regenerator steam to a carbon dioxide recovery unit for use in capturing carbon dioxide from flue gas exhaust of the steam generator.   
     
     
         2 . The method according to  claim 1 , further comprising heat exchanging combustion exhaust of a regenerator boiler for the carbon dioxide recovery unit with air supplied to the steam generator. 
     
     
         3 . The method according to  claim 1 , further comprising heat exchanging combustion exhaust of a regenerator boiler for the carbon dioxide recovery unit with the water prior to the water entering the steam generator. 
     
     
         4 . The method according to  claim 1 , wherein the blowdown without additional steam input provides all steam requirements for solvent regeneration in the carbon dioxide recovery unit. 
     
     
         5 . The method according to  claim 1 , wherein all the blowdown is flashed to produce the regenerator steam without diverting energy content of the blowdown. 
     
     
         6 . The method according to  claim 1 , further comprising recovering products from the formation and heat exchanging at least some of the products with the water prior to the water entering the steam generator. 
     
     
         7 . The method according to  claim 1 , wherein the first pressure is between 5000 kilopascals (kPa) and 11,000 kPa and the second pressure is between 325 kPa and 425 kPa. 
     
     
         8 . The method according to  claim 1 , wherein the carbon dioxide recovery unit is based on amine solution absorption of carbon dioxide. 
     
     
         9 . The method according to  claim 1 , wherein the regenerator steam is used to liberate carbon dioxide from an amine solution in the carbon dioxide recovery unit. 
     
     
         10 . The method according to  claim 1 , wherein the steam generator is a once-through steam generator. 
     
     
         11 . The method according to  claim 1 , wherein the injection steam is all saturated steam produced by the steam generator at the first pressure. 
     
     
         12 . The method according to  claim 1 , further comprising compressing and sequestering a carbon dioxide output from the carbon dioxide recovery unit. 
     
     
         13 . The method according to  claim 1 , wherein the combustion exhaust of a regenerator boiler for the carbon dioxide recovery unit is combined with the flue gas exhaust of the steam generator before being heat exchanged with one of air and the water, which is thereby preheated and supplied to the steam generator. 
     
     
         14 . A method of steam assisted oil recovery integrated with carbon dioxide capture, comprising:
 feeding water to a steam generator that produces injection steam and liquid blowdown separated from the injection steam at a first pressure;   introducing the injection steam into a formation for the steam assisted oil recovery;   flashing the blowdown at a second pressure lower than the first pressure to provide regenerator steam and condensate; and   supplying the regenerator steam to a carbon dioxide recovery unit for use in capturing carbon dioxide from flue gas exhaust of the steam generator, wherein the blowdown without additional steam input provides all steam requirements for solvent regeneration in the carbon dioxide recovery unit.   
     
     
         15 . The method according to  claim 14 , wherein all the injection steam is injected into the formation and is all saturated steam produced by the steam generator at the first pressure. 
     
     
         16 . A method of steam assisted oil recovery integrated with carbon dioxide capture, comprising:
 feeding water to a steam generator that produces injection steam and liquid blowdown separated from the injection steam at a first pressure;   introducing the injection steam into a formation for the steam assisted oil recovery;   flashing the blowdown at a second pressure lower than the first pressure to provide regenerator steam and condensate;   supplying the regenerator steam to a carbon dioxide recovery unit for use in capturing carbon dioxide from flue gas exhaust of the steam generator; and   passing combustion exhaust of a regenerator boiler for the carbon dioxide recovery unit through a heat exchanger to preheat one of air and the water that are then supplied to the steam generator.   
     
     
         17 . The method according to  claim 16 , wherein the combustion exhaust of the regenerator boiler preheats the air supplied to the steam generator. 
     
     
         18 . The method according to  claim 16 , wherein the combustion exhaust of the regenerator boiler preheats the water supplied to the steam generator. 
     
     
         19 . The method according to  claim 16 , wherein the combustion exhaust of the regenerator boiler is combined with the flue gas exhaust of the steam generator before being passed through the heat exchanger. 
     
     
         20 . The method according to  claim 16 , wherein the carbon dioxide recovery unit is based on amine solution absorption of carbon dioxide and the regenerator steam is used to liberate carbon dioxide from the amine solution in the carbon dioxide recovery unit.