Method and facility for operating an in-situ leach mine

Abstract

An operating method for an in situ leach mine comprises a routine phase implemented at the end of life of a block (3) of cells (5) of the mine, including collecting the leachate produced by at least one cell being recycled (5) in the block (3), the leachate forming the recycled leachate; and injecting the recycled leachate into at least one cell (5) of said block (3).

What is claimed is: 
     
         1 - 18 . (canceled) 
     
     
         19 . A method of exploiting a mine comprising at least one chemical component by in-situ leaching, the mine comprising a plurality of cells each equipped with at least one injection well configured for injection of a leach liquor into said cell and at least one production well configured for collecting a leachate containing the at least one chemical component moving upwards from said cell, the method comprising:
 when a block of the cells is at the end of its life, a routine phase comprising:
 collecting the leachate produced by at least one of the cells being recycled in said block, said leachate forming the recycled leachate; and 
 injecting the recycled leachate into at least one of the cells of said block. 
   
     
     
         20 . The method according to  claim 19 , further comprising treating the recycled leachate before the injecting of the recycled leachate into the at least one cell of said block. 
     
     
         21 . The method according to  claim 20 , wherein the treating of the recycled leachate before the injecting of the recycled leachate into the at least one cell of said block includes acidifying the recycled leachate. 
     
     
         22 . The method according to  claim 19 , wherein said routine phase comprises collecting the leachate produced by at least one production cell of the cells of said block and transferring the leachate to a treatment plant, said leachate forming the transferred leachate, the at least one chemical component being separated from the leachate transferred in the treatment plant. 
     
     
         23 . The method according to  claim 22 , wherein during the injecting of the recycled leachate into at least one cell of said block, the recycled leachate is injected into the at least one production cell. 
     
     
         24 . The method according to  claim 22 , wherein during said routine phase, the leach liquor is injected into the cells being recycled concomitantly with the collection of the recycled leachate. 
     
     
         25 . The method according to  claim 22 , wherein during said routine phase, the leach liquor is injected into the at least one production cell concomitantly with the collection of the transferred leachate. 
     
     
         26 . The method according to  claim 22 , wherein at the end of said routine phase, the operation of the at least one cell being recycled is stopped, and a new phase starts in which:
 the at least one cell into which the leachate recycled is injected in said routine phase becomes the at least one cell being recycled during the new phase, and   the leachate recycled during the new phase is injected into at least one new cell of said block.   
     
     
         27 . The method according to  claim 26 , wherein the block of cells is traversed by an underground flow flowing in a determined direction, the operation of the cells of the block being stopped progressively according to the said determined direction of the underground flow. 
     
     
         28 . The method according to  claim 19 , wherein said routine phase comprises a separation operation during which a phase concentrated in the at least one chemical component is separated from the recycled leachate. 
     
     
         29 . The method according to  claim 28 , wherein the concentrated phase is stored in-situ for a period of time and then transferred to a treatment plant, with the at least one chemical component being separated from the concentrated phase in the treatment plant. 
     
     
         30 . The method according to  claim 28 , wherein all of the cells of the block are being recycled and the recycled leachate is reinjected into all of the cells of the block. 
     
     
         31 . An operating facility for operating a mine by in-situ leaching for at least one chemical component, the mine comprising at least one block having a plurality of cells, the operating facility comprising:
 at least one injection well for each cell of said block configured for injection of a leach liquor into said cell;   at least one production well for each cell of said block configured to take a leachate containing the at least one chemical component moving upwards from said cell;   a recycle manifold;   a plurality of collection pipes each fluidly connecting one of the production wells to the recycle manifold, each collection pipe being equipped with a collection cut-off device configured for selectively authorizing or prohibiting the circulation of leachate collected in the corresponding collection pipe; and   a supply assembly for supplying the injection wells, configured to selectively place the recycle manifold in fluid communication with one or more of the injection wells.   
     
     
         32 . The operating facility according to  claim 31 , further comprising a unit for treating the recycled leachate before injection into the or each injection well. 
     
     
         33 . The operating facility according to  claim 32 , wherein the unit for treating the recycled leachate before injection into the or each injection well is configured for acidifying the recycled leachate. 
     
     
         34 . The operating facility according to  claim 31 , further comprising:
 a production manifold configured to be connected to a treatment plant, the at least one chemical component being separated from the leachate in the treatment plant; and   a plurality of production pipes, each fluidly connecting one of the production wells to the production manifold, each production pipe being equipped with a production cut-off device configured for selectively authorizing or prohibiting the flow of leachate in the corresponding production pipe.   
     
     
         35 . The operating facility according to  claim 31 , further comprising a separation module arranged upstream of the supply assembly of the injection wells and configured to separate a phase concentrated in the at least one chemical component from the recycled leachate. 
     
     
         36 . The operating facility according to  claim 35 , further comprising in-situ storage of the concentrated phase, and a module for transferring the concentrated phase from the separation module to a treatment plant, with the at least one chemical component being separated from the concentrated phase in the treatment plant. 
     
     
         37 . The operating facility according to  claim 31 , further comprising a plurality of recycling pipes, each fluidly connecting the recycle manifold to one of the supply wells, each recycle pipe being equipped with a recycle cut-off device configured for selectively authorizing or prohibiting the circulation in the corresponding recycle pipe. 
     
     
         38 . The operating facility according to  claim 31 , further comprising:
 a supply manifold, configured to be connected to a leach liquor supply unit;   a plurality of supply pipes, each fluidly connecting the supply manifold to one of the supply wells, each supply pipe being equipped with a supply cut-off device configured for selectively authorizing or prohibiting the circulation in the corresponding supply pipe.