Hydrometallurgical process and method for recovering metals

Abstract

A mineral processing facility is provided that includes a cogen plant to provide electrical energy and waste heat to the facility and an electrochemical acid generation plant to generate, from a salt, a mineral acid for use in recovering valuable metals.

1 - 15 . (canceled) 
     
     
         16 . A facility, comprising:
 a mill to at least one of comminute a feed material comprising a valuable metal-containing mineral and form, from the valuable metal-containing mineral, a concentrate containing the valuable metal-containing mineral;   a process plant to recover the valuable metal from the valuable metal-containing mineral, wherein at least one of the mill and process plant generate a byproduct salt solution from a mineral acid and a base; and   an electrochemical acid generation plant comprising at least one of a chloralkali and bipolar membrane electrodialysis cell to generate the mineral acid and base from the byproduct salt solution and provide the mineral acid to at least one of the mill and process plant.   
     
     
         17 . The facility of  claim 16 , wherein the valuable metal is a rare earth, wherein the acid component is hydrochloric acid, wherein the salt in the byproduct salt solution is one or more of sodium chloride and potassium chloride, wherein the base is one or more of sodium hydroxide and potassium hydroxide, and wherein the valuable metal product is a rare earth oxide. 
     
     
         18 . The facility of  claim 16 , wherein the at least one of a chloralkali and bipolar membrane electrodialysis cell is the bipolar membrane electrodialysis cell, wherein the valuable metal is one or more of copper, beryllium, nickel, iron, lead, molybdenum, and manganese, wherein the acid component is nitric acid, wherein the salt in the byproduct salt solution is one or more of sodium nitrate and potassium nitrate, and wherein the base is one or more of sodium and potassium hydroxide. 
     
     
         19 . The facility of  claim 16 , wherein the at least one of a chloralkali and bipolar membrane electrodialysis cell is the bipolar membrane electrodialysis cell, wherein the valuable metal is uranium, wherein the acid component is phosphoric acid, wherein the salt in the byproduct salt solution is one or more of sodium phosphate and potassium phosphate, and wherein the base is one or more of sodium and potassium hydroxide. 
     
     
         20 . The facility of  claim 16 , wherein the at least one of a chloralkali and bipolar membrane electrodialysis cell is the bipolar membrane electrodialysis cell, wherein the valuable metal is one or more of a platinum group metal, copper, beryllium, nickel, iron, lead, molybdenum, aluminum, germanium, uranium, gold, silver, cobalt, zinc, cobalt, tin, titanium, chromium, and manganese, wherein the salt in the byproduct salt solution is one or more of sodium sulfate and potassium sulfate, wherein the acid component is sulfuric acid, and wherein the base is one or more of sodium and potassium hydroxide. 
     
     
         21 . The facility of  claim 16 , wherein the valuable metal is one or more of yttrium, scandium, a lanthanide, a platinum group metal, copper, chromium, beryllium, nickel, iron, lead, molybdenum, aluminum, germanium, uranium, gold, silver, cobalt, zinc, cobalt, tin, titanium, and manganese, wherein the salt in the byproduct salt solution is one or more of sodium chloride and potassium chloride, wherein the acid component is hydrochloric acid, and wherein the base is one or more of sodium and potassium hydroxide. 
     
     
         22 . The facility of  claim 16 , wherein the acid component is hydrochloric acid, wherein the electrochemical acid generation plant produces hydrogen gas and chlorine gas, and reacts chlorine gas with hydrogen gas to produce hydrochloric acid. 
     
     
         23 . The facility of  claim 16 , wherein the electrochemical acid generation plant:
 removes at least most of a selected polyvalent impurity from the byproduct salt solution to form a purified salt solution; and   introduces the purified salt solution into the at least one of a chloralkali and bipolar membrane electrodialysis cell to form the acid component and base.   
     
     
         24 . The facility of  claim 23 , wherein the selected polyvalent impurity is a cation, wherein the selected polyvalent cation is removed by precipitation induced by a pH change resulting from contact of the base with the byproduct salt solution, and wherein the electrochemical acid generation plant:
 contacts the purified salt solution with an ion exchange resin to remove additional polyvalent cationic impurities;   therafter processes the purified salt solution by a salt concentrator to form a concentrated and purified salt solution; and   introduces a concentrated and purified solution and a mineral acid into an anolyte recirculation tank, wherein the concentrated and purified solution is introduced into the at least one of a chloralkali and bipolar membrane electrodialysis cell.   
     
     
         25 . The facility of  claim 16 , further comprising:
 a cogen plant to provide electrical and waste thermal energy to one or more of the mill and process plant.   
     
     
         26 . The facility of  claim 16 , wherein the byproduct salt solution comprises an organic contaminant and wherein the electrochemical acid generation plant removes at least most of the organic contaminant to form a purified salt solution, wherein the purified salt solution is introduced into the at least one of a chloralkali and bipolar membrane electrodialysis cell to form the acid component and base. 
     
     
         27 . A system, comprising:
 a mill to at least one of comminute a feed material comprising a valuable metal-containing mineral and form, from the valuable metal-containing mineral, a concentrate containing the valuable metal-containing mineral;   a process plant to recover the valuable metal from the valuable metal-containing mineral; and   a cogen plant to provide electrical energy and waste heat to at least one of the mill and process plant.   
     
     
         28 . The system of  claim 27 , further comprising:
 an electrochemical acid generation plant comprising at least one of a chloralkali and bipolar membrane electrodialysis cell to generate the mineral acid and base from the byproduct salt solution and provide the mineral acid to at least one of the mill and process plant.   
     
     
         29 . The system of  claim 28 , wherein the valuable metal is a rare earth, wherein the acid component is hydrochloric acid, wherein the salt in the byproduct salt solution is one or more of sodium chloride and potassium chloride, wherein the base is one or more of sodium hydroxide and potassium hydroxide, and wherein the valuable metal product is a rare earth oxide. 
     
     
         30 . The system of  claim 28 , wherein the at least one of a chloralkali and bipolar membrane electrodialysis cell is the bipolar membrane electrodialysis cell, wherein the valuable metal is one or more of copper, beryllium, nickel, iron, lead, molybdenum, and manganese, wherein the acid component is nitric acid, wherein the salt in the byproduct salt solution is one or more of sodium nitrate and potassium nitrate, and wherein the base is one or more of sodium and potassium hydroxide. 
     
     
         31 . The system of  claim 28 , wherein the at least one of a chloralkali and bipolar membrane electrodialysis cell is the bipolar membrane electrodialysis cell, wherein the valuable metal is uranium, wherein the acid component is phosphoric acid, wherein the salt in the byproduct salt solution is one or more of sodium phosphate and potassium phosphate, and wherein the base is one or more of sodium and potassium hydroxide. 
     
     
         32 . The system of  claim 28 , wherein the at least one of a chloralkali and bipolar membrane electrodialysis cell is the bipolar membrane electrodialysis cell, wherein the valuable metal is one or more of a platinum group metal, copper, beryllium, nickel, iron, lead, molybdenum, aluminum, germanium, uranium, gold, silver, cobalt, zinc, cobalt, tin, titanium, chromium, and manganese, wherein the salt in the byproduct salt solution is one or more of sodium sulfate and potassium sulfate, wherein the acid component is sulfuric acid, and wherein the base is one or more of sodium and potassium hydroxide. 
     
     
         33 . The system of  claim 28 , wherein the valuable metal is one or more of yttrium, scandium, a lanthanide, a platinum group metal, copper, chromium, beryllium, nickel, iron, lead, molybdenum, aluminum, germanium, uranium, gold, silver, cobalt, zinc, cobalt, tin, titanium, and manganese, wherein the salt in the byproduct salt solution is one or more of sodium chloride and potassium chloride, wherein the acid component is hydrochloric acid, and wherein the base is one or more of sodium and potassium hydroxide. 
     
     
         34 . The system of  claim 28 , wherein the acid component is hydrochloric acid, wherein the electrochemical acid generation plant produces hydrogen gas and chlorine gas, and reacts chlorine gas with hydrogen gas to produce hydrochloric acid. 
     
     
         35 . The system of  claim 28 , wherein the electrochemical acid generation plant:
 removes at least most of a selected polyvalent impurity from the byproduct salt solution to form a purified salt solution; and   introduces the purified salt solution into the at least one of a chloralkali and bipolar membrane electrodialysis cell to form the acid component and base.   
     
     
         36 . The system of  claim 35 , wherein the selected polyvalent impurity is a cation, wherein the selected polyvalent cation is removed by precipitation induced by a pH change resulting from contact of the base with the byproduct salt solution, and wherein the electrochemical acid generation plant:
 contacts the purified salt solution with an ion exchange resin to remove additional polyvalent cationic impurities;   therafter processes the purified salt solution by a salt concentrator to form a concentrated and purified salt solution; and   introduces a concentrated and purified solution and a mineral acid into an anolyte recirculation tank, wherein the concentrated and purified solution is introduced into the at least one of a chloralkali and bipolar membrane electrodialysis cell.   
     
     
         37 . The system of  claim 28 , further comprising:
 a cogen plant to provide electrical and waste thermal energy to one or more of the mill and process plant.   
     
     
         38 . The system of  claim 28 , wherein the byproduct salt solution comprises an organic contaminant and wherein the electrochemical acid generation plant removes at least most of the organic contaminant to form a purified salt solution, wherein the purified salt solution is introduced into the at least one of a chloralkali and bipolar membrane electrodialysis cell to form the acid component and base. 
     
     
         39 - 52 . (canceled)