Method and apparatus for in-situ radiofrequency assisted gravity drainage of oil (ragd)

Abstract

The present invention relates generally to a radiofrequency reactor for use in thermally recovering oil and related materials. The radiofrequency reactor includes a radiofrequency antenna configured to be positioned within a well, where the well is provided within an area in which crude oil exists in the ground. The radiofrequency antenna includes a cylindrically-shaped radiating element for radiating radiofrequency energy into the area in which crude oil exists. The cylindrically-shaped radiating element is configured to allow passage of fluids there through. The radiofrequency reactor also includes a radiofrequency generator electrically coupled to the radiofrequency antenna. The radiofrequency reactor is operable to control the radiofrequency energy generated.

1 . A radiofrequency reactor for use in thermally recovering oil and related materials, the reactor comprising:
 a radiofrequency antenna configured to be positioned within a well provided within an area in which crude oil exists in the ground, the radiofrequency antenna including a cylindrically-shaped radiating element for radiating radiofrequency energy into the area in which crude oil exists, the cylindrically-shaped radiating element configured to allow passage of fluids there through; and   a radiofrequency generator electrically coupled to the radiofrequency antenna and operable to control the radiofrequency energy generated.   
   
   
       2 . The radiofrequency reactor of  claim 1  wherein the cylindrically-shaped radiating element includes a plurality of apertures for allowing passage of the fluids. 
   
   
       3 . The radiofrequency reactor of  claim 2  wherein the plurality of apertures have dimensions selected on the basis of the frequency of the radiofrequency energy. 
   
   
       4 . The radiofrequency reactor of  claim 1  further comprising a coaxial cable for coupling the radiofrequency antenna to the radiofrequency generator. 
   
   
       5 . The radiofrequency reactor of  claim 1 , further comprising a choke assembly positioned between the radiofrequency antenna and radiofrequency generator to maximize transmission of the radiofrequency energy to the radiofrequency antenna. 
   
   
       6 . The radiofrequency reactor of  claim 5 , wherein the choke assembly includes an inner conductive casing surrounded by a dielectric portion, the assembly running at least one-quarter of a maximal frequency to be emitted, and the inner casing electrically coupled to the radiofrequency generator and to the inside of the well wall. 
   
   
       7 . The radiofrequency reactor of  claim 6 , wherein the assembly runs an odd-multiple of one-quarter of a maximal frequency to be emitted. 
   
   
       8 . The radiofrequency reactor of  claim 1 , wherein the reactor is one in a plurality of reactors and the radiofrequency generator operable to control the radiofrequency energy generated is configured to work in conjunction with the radiofrequency generators of the plurality. 
   
   
       9 . The radiofrequency reactor of  claim 1 , wherein the radiofrequency generator operable to control the radiofrequency energy generated is configured to control the phase of the radiofrequency energy emitted. 
   
   
       10 . A method of retrofitting an oil well for extracting crude oil, the method comprising:
 electrically coupling a radiofrequency generator to a radiofrequency antenna including a cylindrically-shaped radiating element for radiating radiofrequency energy into the crude oil; and   controlling the radiofrequency generator to provide radiofrequency energy to the radiofrequency antenna.   
   
   
       11 . The method of  claim 10 , further comprising positioning the radiofrequency generator proximally to the well surface and electrically coupling the radiofrequency generator to the cylindrically-shaped radiating element via a coaxial cable. 
   
   
       12 . The method of  claim 11 , further comprising connecting a choke assembly between the radiofrequency generator and the cylindrically-shaped radiating element. 
   
   
       13 . The method of  claim 10 , wherein controlling the radiofrequency generator to provide radiofrequency energy to the radiofrequency antenna comprises controlling the phasing of the radiofrequency energy emitted.