Heat Pipes for a Single Well Engineered Geothermal System

Abstract

A heat pipe or a bundle of heat pipes for transporting geothermal heat in a well is provided. As the temperature rises at one end of the heat pipe, the operating fluid turns to a vapor which absorbs the latent heat. The hot vapor within the heat pipe flows to the cooler end of the heat pipe where it then condenses and releases the latent heat. The condensed fluid then flows back to the hot side of the heat pipe and the process repeats itself.

What is claimed: 
     
         1 . An apparatus for transporting geothermal heat from a geothermal well to a surface comprising:
 at least one heat pipe comprising a wall surrounding a central tube or chamber;   a fluid contained within the central tube or chamber;   a first apparatus end that is closed and positioned at a first end of the heat pipe, and a second apparatus end that is closed and positioned at a second end of the heat pipe;   wherein the apparatus is configured to be in a vertical or inclined position in the geothermal well, and   wherein the fluid absorbs geothermal heat at the first apparatus end as it transitions to a vapor, rises to the second apparatus end, releases geothermal heat at the second apparatus end as it condenses back to a liquid state, and returns to the first apparatus end.   
     
     
         2 . The apparatus of  claim 1 , wherein the first apparatus end is configured for placement in the geothermal well and the second apparatus end is configured for placement near the surface. 
     
     
         3 . The apparatus of  claim 1 , wherein the wall of the at least one heat pipe further comprises:
 a copper layer surrounding the central tube or chamber;   a steel layer surrounding the copper layer; and   a titanium layer surrounding the steel layer; and   wherein at least the copper layer and the titanium layer are non-porous to water.   
     
     
         4 . The apparatus of  claim 1 , wherein the wall of the at least one heat pipe further comprises:
 an internal coating layer surrounding the central tube or chamber;   an iron layer surrounding the internal coating layer, which is configured to protect the iron layer from the fluid in the central tube or chamber; and   an external coating layer of a caustic resistant material surrounding the iron layer; and   wherein at least the internal and external coating layers are non-porous to water.   
     
     
         5 . The apparatus of  claim 1 , wherein the at least one heat pipe is made from titanium. 
     
     
         6 . The apparatus of  claim 1 , wherein the at least one heat pipe comprises:
 a plurality of pipes welded together vertically;   a base section secured to a base of the plurality of pipes;   a threaded plug configured to be secured to an uppermost pipe of the plurality of pipes, which comprises corresponding threading; and   a port comprised in the uppermost pipe of the plurality of pipes and positioned so as to be covered by the threaded plug when the threaded plug is fully inserted into the uppermost pipe; and   wherein during assembly of the at least one heat pipe, the threaded plug is partially inserted into the plurality of pipes, the fluid is injected into the at least one heat pipe through the port, and the threaded plug is then inserted further into the plurality of pipes to cover the port.   
     
     
         7 . The apparatus of  claim 6 , wherein the plurality of pipes, the threaded plug and the base section are made from titanium. 
     
     
         8 . The apparatus of  claim 1 , wherein the at least one heat pipe comprises a plurality of heat pipes arranged in a bundle surrounding a bundle central tube or chamber comprising the fluid. 
     
     
         9 . The apparatus of  claim 8 , wherein the bundle of heat pipes comprises at least six heat pipes surrounding the bundle central tube or chamber, each of the heat pipes comprising the wall surrounding the central tube or chamber. 
     
     
         10 . The apparatus of  claim 8 , wherein the bundle of heat pipes comprises a plurality of bundles of heat pipes. 
     
     
         11 . The apparatus of  claim 10 , wherein the plurality of bundles of heat pipes comprises at least six bundles of heat pipes and comprises a total of at least seventy-two heat pipes. 
     
     
         12 . The apparatus of  claim 11 , wherein the plurality of bundles of heat pipes are arranged to surround a further central tube or chamber comprising the fluid. 
     
     
         13 . The apparatus of  claim 1 , wherein the at least one heat pipe comprises appendages branching outwardly from a central heat pipe configured to insertion into horizontal or angled bore holes in the geothermal well. 
     
     
         14 . The apparatus of  claim 1 , wherein the at least one heat pipe is made from copper. 
     
     
         15 . The apparatus of  claim 1 , wherein the at least one heat pipe is made from a copper-nickel alloy. 
     
     
         16 . The apparatus of  claim 1 , wherein the fluid is water.