System and method for producing methane from a methane hydrate formation

Abstract

A completion system includes a first borehole structure having a first section formed proximate to a volume of methane hydrate located at a subsurface location. A second borehole structure has a second section formed proximate to the volume of methane hydrate, the first section positioned deeper than the second section with respect to gravity. A first string is positioned in the first borehole structure and arranged to convey a heat-bearing fluid through the first string into contact with a volume of methane hydrate in order to liberate methane from the methane hydrate. A second string is positioned in the second borehole structure and arranged to produce the methane.

What is claimed is: 
     
         1 . A completion system, comprising:
 a first borehole structure having a first section formed proximate to a volume of methane hydrate located at a subsurface location;   a second borehole structure having a second section formed proximate to the volume of methane hydrate, the first section positioned deeper than the second section with respect to gravity;   a first string positioned in the first borehole structure and arranged to convey a heat-bearing fluid through the first string into contact with a volume of methane hydrate in order to liberate methane from the methane hydrate; and   a second string positioned in the second borehole structure and arranged to produce the methane.   
     
     
         2 . The system of  claim 1 , wherein the first and second borehole structures comprise a first lateral and a second lateral of a multi-lateral borehole. 
     
     
         3 . The system of  claim 1 , wherein the first and second borehole structures comprise a first borehole and a second borehole separate from the first borehole. 
     
     
         4 . The system of  claim 1 , wherein the heat-bearing fluid includes steam. 
     
     
         5 . The system of  claim 1 , wherein the heat-bearing fluid comprises one or more components productive of an exothermic reaction. 
     
     
         6 . The system of  claim 1 , wherein the second string includes one or more screen assemblies that enable entry of the methane into the second string. 
     
     
         7 . The system of  claim 1 , further comprising one or more instrumentation lines disposed in the first string, the second string, or a combination including at least one of the foregoing. 
     
     
         8 . The system of  claim 7 , wherein the one or more instrumentation lines are arranged to enable one or more parameters related to formation of the methane hydrate to be sensed. 
     
     
         9 . The system of  claim 8 , wherein the one or more parameters include temperature, pressure, or a combination including at least one of the foregoing. 
     
     
         10 . The system of  claim 1 , wherein the system further comprises means to control at least one parameter of methane hydrate other than heat. 
     
     
         11 . The system of  claim 1 , wherein the first string comprises one or more valves for selectively controlling communication of the heat-bearing fluid with the volume. 
     
     
         12 . The system of  claim 1 , further comprising one or more Electric Submersible Pumps. 
     
     
         13 . A method for producing methane from methane hydrate comprising:
 conveying a heat bearing fluid to a formation containing methane hydrate through a first borehole section located deeper than a second borehole section relative to gravity;   liberating methane from the methane hydrate; and   receiving the methane in the second borehole section.   
     
     
         14 . The method of  claim 13  wherein the collecting includes selectively leaving behind constituents of the liberation of methane that are not methane. 
     
     
         15 . The method of  claim 14  wherein the selectively is by gravity. 
     
     
         16 . The method of  claim 13  wherein the method further includes heating the produced methane in other locations of the borehole than the section. 
     
     
         17 . The method of  claim 13  wherein the heat-bearing fluid includes steam. 
     
     
         18 . The method of  claim 13  wherein the heat-bearing fluid comprises components productive of an exothermic reaction. 
     
     
         19 . A method for producing methane hydrate comprising:
 controlling at least one parameter of methane hydrate stability so as to destabilize the methane hydrate;   liberating methane from the methane hydrate pursuant to the destabilization.   
     
     
         20 . The method of  claim 19  further comprising controlling one or more additional parameters of methane hydrate stability. 
     
     
         21 . The method of  claim 20  wherein the one or more additional parameters include chemistry of environment and pressure.