Device and method for crushing rock by means of pulsed electric energy

Abstract

The invention relates to a method for processing submerged material at the bottom of a body of water, like the bottom of the sea, by application of electric energy, comprising providing electrodes in a process zone proximate the material for providing an electric current through the material for crushing the material, and displacing of fluid of the body of water away from the process zone to outside the process zone before application of the electric energy.

1 . Method for processing submerged material at the bottom of a body of water, like the bottom of the sea, by application of electric energy, wherein the method comprises providing electrodes for application of the electric energy in a process zone proximate the material for crushing the material, and displacing of fluid of the body of water away from the process zone to outside the process zone before application of the electric energy. 
     
     
         2 . Method according to  claim 1 , wherein the displacing of fluid of the body of water away from the process zone comprises introducing an electrically insulating body in the process zone. 
     
     
         3 . Method according to  claim 1 , wherein the displacing of fluid of the body of water away from the process zone comprises introducing an electrically insulating fluid ( 7 ) under pressure in the process zone. 
     
     
         4 . Method according to  claim 3 , wherein the electrically insulating fluid under pressure has a low electrical conductivity. 
     
     
         5 . Method according to  claim 3 , comprising on site producing the electrically insulating fluid. 
     
     
         6 . Method according to  claim 1 , wherein the submerged material comprises rock. 
     
     
         7 . Method according to  claim 2 , wherein fluid of the body of water is partly displaced away from the process zone to outside the process zone such that a layer of fluid of the body of water remains on top of the submerged material before application of the electric energy. 
     
     
         8 . Method according to  claim 2 , wherein substantially all fluid of the body of water is displaced away from the process zone to outside the process zone such that the application of the electric energy causes providing an electric current through the material. 
     
     
         9 . Device for processing submerged material at the bottom of a body of water, like the bottom of the sea, by application of electric energy, wherein the device comprises electrodes configured to be arranged in a process zone proximate the material for providing an electric current through the material, and means for displacing fluid of the body of water away from the process zone to outside the process zone before application of the electric energy. 
     
     
         10 . Device according to  claim 9 , wherein the means for displacing fluid of the body of water comprises an electrically insulating body arranged proximate the electrodes. 
     
     
         11 . Device according to  claim 9 , where the means for displacing fluid of the body of water comprise a discharge opening arranged proximate the electrodes for introducing an electrically insulating fluid under pressure in the process zone. 
     
     
         12 . Device according to  claim 11 , comprising a container filled with the electrically insulating fluid, which container is in fluid connection with the discharge opening. 
     
     
         13 . Device according to  claim 11 , wherein the electrically insulating fluid has a low electrical conductivity. 
     
     
         14 . Device according to a  claim 9 , comprising a shielding member arranged around the process zone for holding the electrically insulating fluid in the process zone. 
     
     
         15 . Device according to  claim 9 , comprising measuring means arranged in the process zone for measuring electrical conductivity in the process zone. 
     
     
         16 . Device according to  claim 9 , wherein the electrodes comprise a pair of concentric electrodes. 
     
     
         17 . Method according to  claim 4 , wherein the electrically insulating fluid under pressure has an electrical conductivity below 500 mS/m. 
     
     
         18 . Method according to  claim 17 , wherein the electrically insulating fluid under pressure has an electrical conductivity below 50 mS/m.