Method of extracting energy from a cavity created by mining operations

Abstract

An energy-extracting mine ventilation system comprises: a ventilation unit for conditioning the intake air of a mine; a network of pipes installed in at least one cavity of the mine, the network of pipes comprising a geothermal fluid circulating therethrough wherein the network is in contact with a minefill material within the cavity and a rock mass; wherein the minefill material transfers energy between the rock mass of the at least one cavity and the thermal fluid; and a heat exchanger unit in fluid communication with the network of pipes and extracting the energy from the thermal fluid The heat exchanger unit is configured to transfer extracted energy directly or indirectly to the ventilation unit in order to condition the intake air of the mine, The extracted energy can be used in a variety of other applications, such as district heating, acid leaching, and water heating.

1 - 10 . (canceled) 
     
     
         11 . Method for extracting energy from at least one cavity of a rock mass, the method comprising:
 placing a hydraulically connected network of geothermal pipes into the at least one cavity;   covering at least part of the network of geothermal pipes with a minefill material such that the cavity is at least partly filled;   circulating a thermal fluid through the network of geothermal pipes;   wherein the minefill material transfers energy between the rock mass of the at least one cavity and the thermal fluid within the network of geothermal pipes; and   extracting energy from the thermal fluid.   
     
     
         12 . The energy extraction method according to  claim 11 , further comprising extracting high temperature energy, higher than 60[deg.]C., from the thermal fluid. 
     
     
         13 . The energy extraction method according to  claim 11 , further comprising extracting low temperature energy, lower than 60[deg.]C., from the thermal fluid. 
     
     
         14 . The energy extraction method according to  claim 11 , further comprising: extracting high temperature energy from the thermal fluid; and converting the extracted high temperature energy into mechanical or electrical power. 
     
     
         15 . The energy extraction method according to  claim 11 , further comprising transferring the extracted energy to a second network of geothermal pipes via a heat exchanger in contact with the first network of geothermal pipes, the second network comprising a second thermal fluid circulating therein. 
     
     
         16 . The energy extraction method according to  claim 11 , further comprising transferring the extracted energy to a ventilation unit in order to condition an intake air of the mining operations. 
     
     
         17 . The energy extraction method according to  claim 11 , wherein the minefill material is in direct contact with the network of pipes and the rock mass. 
     
     
         18 . The energy extraction method according to  claim 11 , wherein the at least one cavity was created by mining operations. 
     
     
         19 . An energy extracting mine ventilation system comprising:
 a ventilation unit for conditioning an intake air of a mine;   a network of pipes adapted to be installed in at least one cavity of the mine, the network of pipes comprising a geothermal fluid circulating therethrough;   minefill material adapted to be positioned in the cavity for transferring energy between a rock mass of the at least one cavity and the thermal fluid; and   a heat exchanger unit adapted to extract energy from the thermal fluid, the heat exchanger unit being configured to transfer extracted energy directly or indirectly to the ventilation unit in order to condition the intake air of the mine.   
     
     
         20 . The ventilation system according to  claims 19 , wherein the at least one cavity is a mine stope. 
     
     
         21 . The ventilation system according to  claim 19 , wherein the minefill material comprises at least one of soil; tailings material, a blend of soil, water and binder; and a blend of tailings material, water and binder. 
     
     
         22 . The ventilation system according to  claim 19 , wherein the minefill material has a porosity range of 0.3 to 0.5 and a thermal conductivity range of 0.4 W/m-K to 10 VV/rn-K. 
     
     
         23 . The ventilation system according to  claim 19 , wherein the minefill material is in direct contact with the network of pipes and the rock mass. 
     
     
         24 - 36 . (canceled) 
     
     
         37 . A system for extracting energy from a mine, comprising:
 a heat transfer system adapted to be installed in at least one stope of the mine;   minefill material adapted to be positioned in the cavity for transferring energy between a rock mass of the at least one cavity and the heat transfer system; and   a heat exchanger unit adapted to extract energy from the heat transfer system.   
     
     
         38 - 55 . (canceled) 
     
     
         56 . The energy extraction method according to  claim 11 , wherein the network of geothermal pipes is substantially completely covered with the minefill material. 
     
     
         57 . The energy extraction method according to  claim 56 , wherein the mine field material is in direct contact with the network of geothermal pipes and the rock mass. 
     
     
         58 . The energy extraction method according to  claim 57 , wherein the cavity is substantially completely filled with the minefill material. 
     
     
         59 . The energy extraction method according to  claim 58 , wherein the at least one cavity is a mine stope. 
     
     
         60 . The ventilation system according to  claim 19 , wherein the network of pipes is in contact with the minefill material within the cavity and a rock mass. 
     
     
         61 . The energy extraction method according to  claim 60 , wherein the heat exchanger unit is in fluid communication with the network of pipes.