Integrated enhanced oil recovery process

Abstract

The present invention relates to an enhanced oil recovery process that is integrated with a synthesis gas generation process, such as gasification or reforming, and an air separation process for generating (i) an oxygen stream for use, for example, in the syngas process or a combustion process, and (ii) a nitrogen stream for EOR use.

1 . An integrated process to (i) produce an acid gas-depleted product gas stream, (ii) produce an oxygen-rich gas stream, (iii) produce a hydrocarbon-containing fluid from an underground hydrocarbon reservoir via a hydrocarbon production well, and (iv) enhance production of the hydrocarbon-containing fluid from the underground hydrocarbon reservoir, the process comprising the steps of:
 (1) injecting a pressurized nitrogen stream into the underground hydrocarbon reservoir to enhance production of the hydrocarbon-containing fluid from the underground hydrocarbon reservoir via the hydrocarbon production well;   (2) recovering the hydrocarbon-containing fluid produced from the hydrocarbon production well;   (3) separating the hydrocarbon-containing fluid into (a) a liquid hydrocarbon product stream and (b) a gaseous hydrocarbon product stream;   (4) producing a synthesis gas stream from a carbonaceous feedstock, the synthesis gas stream comprising (a) carbon dioxide, and (b) at least one of hydrogen and methane;   (5) treating the synthesis gas stream in an acid gas removal unit to produce the acid gas-depleted synthesis gas stream and a carbon dioxide-rich stream;   (6) optionally treating the gaseous hydrocarbon product stream in the acid gas removal unit to produce an acid-gas depleted gaseous hydrocarbon product stream;   (7) optionally combusting at least a portion of one or more of the acid gas-depleted synthesis gas stream, the gaseous hydrocarbon product stream and the acid-gas depleted gaseous hydrocarbon product stream;   (8) separating an air stream into the oxygen-rich stream and a nitrogen-rich stream; and   (9) pressurizing the nitrogen-rich stream to generate the pressurized nitrogen stream, wherein at least a portion of the oxygen-rich stream is used in one or both of steps (4) and (7).   
     
     
         2 . The process of  claim 1 , wherein at least a portion of one or more of the acid gas-depleted synthesis gas stream, the gaseous hydrocarbon product stream and the acid-gas depleted gaseous hydrocarbon product stream is combusted, and at least a portion of the oxygen-rich stream is used for the combustion. 
     
     
         3 . The process of  claim 1 , wherein at least a portion of the oxygen-rich stream is used to produce the synthesis gas stream. 
     
     
         4 . The process of  claim 1 , wherein the synthesis gas stream is produced by a catalytic steam methane reforming process utilizing a methane-containing stream as the carbonaceous feedstock. 
     
     
         5 . The process of  claim 1 , wherein the synthesis gas stream is produced by a non-catalytic gaseous partial oxidation process utilizing a methane-containing stream as the carbonaceous feedstock. 
     
     
         6 . The process of  claim 1 , wherein the synthesis gas stream is produced by a catalytic autothermal reforming process utilizing a methane-containing stream as the carbonaceous feedstock. 
     
     
         7 . The process of  claim 1 , wherein the synthesis gas stream is produced by a non-catalytic thermal gasification process utilizing a non-gaseous carbonaceous material as the carbonaceous feedstock. 
     
     
         8 . The process of  claim 1 , wherein the synthesis gas stream comprises hydrogen and one or both of carbon monoxide and carbon dioxide. 
     
     
         9 . The process of  claim 1 , wherein the synthesis gas stream is produced by a catalytic hydromethanation process utilizing a non-gaseous carbonaceous material as the carbonaceous feedstock. 
     
     
         10 . The process of  claim 1 , wherein the synthesis gas stream comprises methane, hydrogen and carbon dioxide, and optionally carbon monoxide. 
     
     
         11 . The process of  claim 1 , wherein at least a portion of the synthesis gas stream is subject to a sour shift to generate a hydrogen-enriched stream. 
     
     
         12 . The process of  claim 1 , wherein the acid-gas depleted product gas stream comprises hydrogen, and at least a portion of the hydrogen is separated to generate a hydrogen product stream and a hydrogen-depleted gas stream. 
     
     
         13 . The process of  claim 1 , wherein the gaseous hydrocarbon product stream is treated in the acid gas removal unit. 
     
     
         14 . The process of  claim 13 , wherein the acid gas-depleted product gas stream comprises an acid gas-depleted gaseous hydrocarbon product stream and an acid gas-depleted synthesis gas stream. 
     
     
         15 . The process of  claim 1 , wherein the carbon dioxide-rich stream generated from acid gas removal is pressurized to generate a pressurized carbon dioxide stream, at least a portion of which is injected into the underground hydrocarbon reservoir. 
     
     
         16 . A process to enhance production of a hydrocarbon-containing fluid from an underground hydrocarbon reservoir via a hydrocarbon production well, by injecting a pressurized nitrogen stream into the underground hydrocarbon reservoir, wherein the pressurized nitrogen stream is generated by a process comprising the steps of:
 (I) recovering the hydrocarbon-containing fluid produced from the hydrocarbon production well;   (II) separating the hydrocarbon-containing fluid into (a) a liquid hydrocarbon product stream and (b) a gaseous hydrocarbon product stream;   (III) producing a synthesis gas stream from a carbonaceous feedstock, the synthesis gas stream comprising (a) carbon dioxide, and (b) at least one of hydrogen and methane;   (IV) treating the synthesis gas stream in an acid gas removal unit to produce an acid gas-depleted synthesis gas stream and a carbon dioxide-rich stream;   (V) optionally treating the gaseous hydrocarbon product stream in the acid gas removal unit to produce an acid-gas depleted gaseous hydrocarbon product stream;   (VI) optionally combusting at least a portion of one or more of the acid gas-depleted synthesis gas stream, the gaseous hydrocarbon product stream and the acid-gas depleted gaseous hydrocarbon product stream;   (VII) separating an air stream into an oxygen-rich stream and a nitrogen-rich stream; and   (VIII) pressurizing the nitrogen-rich stream to generate the pressurized nitrogen stream,   wherein at least a portion of the oxygen-rich stream is used in one or both of steps (III) and (VI).   
     
     
         17 . An apparatus for producing a hydrocarbon-containing fluid, an acid gas-depleted product gas stream and an oxygen-rich stream, the apparatus comprising:
 (A) a synthesis gas production system adapted to produce a synthesis gas from a carbonaceous feedstock, the synthesis gas comprising (i) carbon dioxide and (ii) at least one of hydrogen and methane;   (B) an injection well in fluid communication with an underground hydrocarbon reservoir comprising a hydrocarbon-containing fluid, the injection well adapted to inject a pressurized nitrogen stream into the underground hydrocarbon reservoir for enhanced oil recovery;   (C) a hydrocarbon production well in fluid communication with the underground hydrocarbon reservoir, the hydrocarbon production well adapted to remove hydrocarbon-containing fluid from the underground hydrocarbon reservoir;   (D) a separation device in fluid communication with the hydrocarbon production well, the separation device adapted (i) to receive the hydrocarbon fluid from the hydrocarbon production well, and (ii) to separate the hydrocarbon fluid into a liquid hydrocarbon product stream and a gaseous hydrocarbon product stream;   (E) an acid gas removal unit in fluid communication with the synthesis gas generation system, the acid gas removal unit adapted to (i) receive the synthesis gas from the synthesis gas generation system, and (ii) treat the synthesis gas to remove acid gases and produce the acid gas-depleted product gas stream and a carbon dioxide-rich stream;   (F) an air separation unit adapted to (i) receive an air stream and (ii) separate the air stream into an oxygen-rich stream and a nitrogen-rich recycle stream; and   (G) a compressor unit in fluid communication with the air separation unit and the injection well, the compressor unit adapted to (i) receive the nitrogen-rich recycle stream, and (ii) compress the nitrogen-rich recycle stream to generate the pressurized nitrogen stream, and (iii) provide the pressurized nitrogen stream to the injection well.   
     
     
         18 . The apparatus of  claim 17 , wherein the injection well is further adapted to inject a pressurized carbon dioxide stream into the underground hydrocarbon reservoir, and the apparatus further comprises a compressor unit in fluid communication with the acid gas removal unit and the injection well, the compressor unit adapted to (i) receive the carbon dioxide-rich stream, and (ii) compress the carbon dioxide recycle stream to generate the pressurized carbon dioxide stream, and (iii) provide the pressurized carbon dioxide stream to the injection well. 
     
     
         19 . The apparatus of  claim 17 , wherein the acid gas removal unit is adapted to receive a combined stream of the synthesis gas and the gaseous hydrocarbon product stream, and treat the combined stream to remove acid gases and produce an acid gas-depleted product gas stream and a carbon dioxide-rich stream. 
     
     
         20 . The apparatus of  claim 17 , wherein the acid gas removal unit is also adapted to receive the gaseous hydrocarbon product stream from the separation device, and treat the gaseous hydrocarbon product stream to remove acid gases and produce an acid gas-depleted gaseous hydrocarbon product stream.