Method for underground recovery of hydrocarbons

Abstract

The present invention discloses a method for installing, operating and servicing wells in a hydrocarbon deposit from a lined shaft and/or tunnel system that is installed above, into or under a hydrocarbon deposit. The entire process of installing the shafts and tunnels as well as drilling and operating the wells is carried out while maintaining isolation between the work space and the ground formation. In one aspect of the invention, well-head devices may be precast into the tunnel or shaft lining to facilitate well installation and operation in the presence of formation pressure and/or potential fluid in-flows. In another aspect of the invention, the tunnel itself can be used as a large diameter well for collecting hydrocarbons and, if required, for injecting steam or diluents into a formation to mobilize heavy hydrocarbons such as heavy crude and bitumen.

1 . A method for extracting hydrocarbons from a hydrocarbon-containing deposit, comprising: 
 (a) forming an underground excavation having a section extending through a hydrocarbon deposit;    (b) forming a substantially fluid impermeable liner extending along the section of the excavation; and    (c) from the section of the excavation, forming, through the liner, a plurality of wells extending into the hydrocarbon deposit, wherein the wells at least one of inject a fluid into the hydrocarbon deposit and extract a hydrocarbon from the deposit.    
   
   
       2 . The method of  claim 1 , wherein the liner, as formed, comprises at least one tool to facilitate at least one of well drilling, well completion, and hydrocarbon extraction from the deposit.  
   
   
       3 . The method of  claim 1 , wherein the at least some of the wells inject a fluid into the hydrocarbon deposit and at least some of the wells extract a hydrocarbon from the deposit, wherein the fluid mobilizes the hydrocarbon for extraction, wherein the fluid is at least one of steam, a diluent, water, carbon dioxide, nitrogen, and air and wherein the liner extends substantially around the periphery of the excavation.  
   
   
       4 . The method of  claim 2 , wherein the tool comprises at least one of an anchor point for engaging a device used in the at least one of well drilling, well completion, and hydrocarbon extraction, and a sensor for measuring and/or monitoring fluid flow and/or formation pressure.  
   
   
       5 . The method of  claim 2 , wherein, after completion, the interior of the excavation is at least substantially sealed from fluids in the well.  
   
   
       6 . The method of  claim 1 , wherein, during formation of the underground excavation, the interior of the excavation behind an excavation device forming the excavation is at least substantially sealed from the hydrocarbon deposit, wherein excavating and muck removal by a cutter head of the excavation device is at a higher pressure than a pressure in the excavation behind the excavation device, and wherein the excavation device is a slurry or earth pressure balance tunnel boring machine.  
   
   
       7 . The method of  claim 1 , wherein the liner is at least partially surrounded by a backfill material positioned between the wall of the excavation and the liner.  
   
   
       8 . Hydrocarbon produced from the wells of  claim 1 .  
   
   
       9 . A method for extracting a hydrocarbon, comprising: 
 (a) providing an underground excavation;    (b) forming a liner in the underground excavation; and    (c) forming a plurality of wells passing through the liner and into a hydrocarbon-containing deposit, wherein the liner, when formed, comprises at least one tool to facilitate at least one of well drilling, well completion, and hydrocarbon production from a well.    
   
   
       10 . The method of  claim 9 , wherein the tool is at least one of: 
 an anchor point for engaging a wellhead control assembly used in the at least one of well drilling, well completion, and hydrocarbon extraction; and    a sensor for measuring and/or monitoring fluid flow and/or formation pressure.    
   
   
       11 . The method of  claim 9 , wherein the tool is a ring assembly embedded in a liner section, the ring assembly engaging a mounting device for a wellhead control assembly and wherein the liner section comprises one or more ring assemblies positioned at selected intervals around the liner section.  
   
   
       12 . The method of  claim 11 , wherein a gasket is positioned at the interface between the mounting device and the ring assembly to form a seal therebetween.  
   
   
       13 . The method of  claim 11 , wherein ring assembly comprises first and second ring halves, each ring half comprising threaded holes spaced at substantially equal angles around the ring half to allow the wellhead control assembly to be positioned at any of a number of angles around the tunnel liner.  
   
   
       14 . The method of  claim 9 , wherein the tool is at least one of an injection port for injecting fluids and a drain port for collecting fluids located between the liner and the adjacent wall of the excavation.  
   
   
       15 . The method of  claim 9 , wherein the tool is a flange operable to engage well-head equipment in communication with a well in spatial proximity to the flange.  
   
   
       16 . Hydrocarbon produced from the wells of  claim 9 .  
   
   
       17 . A liner for an excavation, comprising: 
 (a) a liner section; and    (b) a tool embedded in the liner section at selected intervals along a length of the section, wherein the tool is at least one of an attachment point, an injection port for a fluid to be injected into a hydrocarbon-containing formation, and a collection port for collection of hydrocarbon-containing fluids from the formation.    
   
   
       18 . The liner of  claim 17 , wherein the tool is an attachment point, wherein a wellhead control assembly is attached to the tool.  
   
   
       19 . The liner of  claim 18 , wherein the tool comprises a ring positioned substantially around the periphery of the liner section and a plurality of connectors positioned at selected intervals along the length of the ring to engage the wellhead control assembly.  
   
   
       20 . The liner of  claim 19 , wherein the ring comprises first and second interconnected ring halves, each half being positioned adjacent to one another and containing a subset of the connectors, and wherein the connectors are positioned at equal angles around the ring, thereby allowing the device to be positioned at any of a number of discrete angles along a length of the ring.  
   
   
       21 . The liner of  claim 18 , wherein the tool comprises a gasket to form a seal between the wellhead control assembly and a surface of the liner.  
   
   
       22 . The liner of  claim 17 , wherein the liner section further comprises a plurality of drain ports for collecting fluids located between the liner and the adjacent wall of the excavation, the plurality of drain ports being in communication with a fluid collection system.  
   
   
       23 . The liner of  claim 17 , wherein the tool is the injection port.  
   
   
       24 . The liner of  claim 17 , wherein the tool is the collection port.  
   
   
       25 . The liner of  claim 23 , wherein injection ports are positioned in an upper portion of a first liner section.  
   
   
       26 . The liner of  claim 25 , wherein a the first liner section comprises collection ports positioned in a lower portion of the liner section.  
   
   
       27 . The liner of  claim 25  wherein the injection ports are elongated and comprise a screen to inhibit particulate material from passing through the ports.  
   
   
       28 . The liner of  claim 26 , wherein the collection ports are elongated and comprise a screen to inhibit particulate material from passing through the ports.  
   
   
       29 . A method for recovering hydrocarbons, comprising: 
 (a) in an underground excavation providing a lined excavation, the lined excavation extending through a hydrocarbon-containing formation, and a liner in the lined excavation comprising a plurality of fluid injection ports;    (b) injecting a fluid, through the fluid injection ports, into the hydrocarbon-containing formation; and    (c) collecting hydrocarbons mobilized by the injected fluid.    
   
   
       30 . The method of  claim 29 , wherein the lined tunnel has an impervious material positioned between at least first and second fluid permeable annular spaces positioned between the liner and a surface of the excavation to inhibit the movement of the injected fluid from the first annular space to the second annular space, wherein the fluid is one of steam and a diluent, and further comprising: 
 (d) transporting the fluid from the surface through the underground excavation to a set of injectors in communication with the injection ports and with the first and second annular spaces, wherein the temperature and/or pressure of the steam is returned to a selected level during transportation.    
   
   
       31 . The method of  claim 29 , wherein the fluid is injected into at least one annular space defined by the liner and a wall of the excavation and in the absence of a well.  
   
   
       32 . The method of  claim 29 , wherein the liner comprises a plurality of collection ports and wherein the hydrocarbons pass through the collection ports in the absence of a well casing.  
   
   
       33 . Hydrocarbon produced from the wells of  claim 29 .  
   
   
       34 . A method for recovering hydrocarbons, comprising: 
 (a) in an underground excavation providing a lined excavation, the lined excavation extending through a hydrocarbon-containing formation, and a liner in the lined excavation comprising a plurality of collection and injection ports;    (b) injecting a fluid into the hydrocarbon-containing formation; and    (c) collecting, at the collection ports, hydrocarbons mobilized by the injected fluid.    
   
   
       35 . The method of  claim 34 , wherein the liner comprises a plurality of injection ports, wherein the lined tunnel has an impervious material positioned between at least first and second fluid permeable annular spaces positioned between the liner and a surface of the excavation to inhibit the movement of the injected fluid from the first annular space to the second annular space, wherein the fluid is steam, and further comprising: 
 (d) transporting the fluid from the surface through the underground excavation to a set of injectors in communication with the injection ports and with the first and second annular spaces, wherein the temperature and/or pressure of the steam is returned to a selected level during transportation.    
   
   
       36 . The method of  claim 34 , wherein the fluid is injected into at least one annular space defined by the liner and a wall of the excavation and in the absence of a well.  
   
   
       37 . The method of  claim 34 , wherein the hydrocarbons pass through the collection ports in the absence of a well casing.  
   
   
       38 . Hydrocarbon produced from the wells of  claim 34 .  
   
   
       39 . A method for recovering hydrocarbons, comprising: 
 (a) forming an excavation in a hydrocarbon-containing formation; and    (b) maintaining an interior of the excavation behind an excavation device substantially sealed from selected fluids in the formation.    
   
   
       40 . The method of  claim 39 , wherein the excavation device is a tunnel boring machine, wherein a first seal is maintained between a cutter head and a muck removal system using a ground modifying material and maintaining the modified excavated material at a pressure that is approximately the pressure of the formation.  
   
   
       41 . The method of  claim 40 , wherein a periphery of the tunnel boring machine shield forms a second seal with a liner section.  
   
   
       42 . The method of  claim 41 , wherein a third seal is formed in the excavation behind the tunnel boring machine using a liner.  
   
   
       43 . The method of  claim 42 , wherein a fourth seal is formed between all the joints of the liner.  
   
   
       44 . The method of  claim 42 , wherein the liner comprises a plurality of interconnected sections and wherein a sealing gasket is positioned between adjacent interconnection sections.  
   
   
       45 . The method of  claim 42 , wherein the liner comprises a plurality of interconnected sections and wherein step (b) comprises: 
 (i) positioning a sealing material between adjacent liner sections;    (ii) interconnecting the adjacent liner sections; and    (iii) the tunnel boring machine apply a force to the interconnected adjacent liner sections, thereby causing the sealing material to form a seal along a joint between the adjacent liner sections.