Integrated hydrometallurgical and pyrometallurgical method for processing ore

Abstract

A process for recovering copper, uranium and one or more precious metals from an ore material, including: a. forming a heap of the ore material; b. subjecting the heap of the ore material to an acidic heap leach using an iron containing acidic leach solution in the presence of an oxygen containing gas, and producing a pregnant leach solution and a ripios; c. subjecting the ripios to flotation to produce a copper containing ripios concentrate and tailings; and d. subjecting the ripios concentrate to a smelting process to produce a smelted copper product. e. recovering copper and uranium from the pregnant leach solution.

1 . A process for recovering copper, uranium and one or more precious metals from an ore material, the process comprising:
 a. forming a heap of an ore material;   b. subjecting the heap of the ore material to an acidic heap leach using an iron comprising acidic leach solution in the presence of an oxygen containing gas, and producing a pregnant leach solution and a ripios;   c. subjecting the ripios to flotation to produce a copper comprising ripios concentrate and tailings; and   d. subjecting the ripios concentrate to a smelting process to produce a smelted copper product.   e. recovering copper and uranium from the pregnant leach solution.   
     
     
         2 . The process of  claim 1 , further comprising:
 f. electro-refining the smelted copper product to produce cathode copper and precious metal-containing anode slimes; and   g. recovering one or more precious metals from the precious metal-containing anode slimes.   
     
     
         3 . The process of  claim 1 , wherein the ore material comprises copper sulphides and uranium minerals. 
     
     
         4 . The process of  claim 1 , wherein the smelting process comprises two smelting stages. 
     
     
         5 . The process of  claim 1 , wherein the smelting process comprises a primary smelting stage and a secondary smelting stage. 
     
     
         6 . The process of  claim 5 , wherein the primary smelting stage is conducted in a matte smelting furnace. 
     
     
         7 . The process of  claim 5 , wherein the secondary smelting stage is conducted in a direct to blister furnace. 
     
     
         8 . The process of  claim 1 , wherein the ore material also comprises an iron containing mineral which partly or wholly comprises any iron containing acidic leach solution. 
     
     
         9 . The process of  claim 8 , wherein the iron containing mineral comprises a gangue mineral such as hematite, siderite, or chlorite. 
     
     
         10 . The process of  claim 1 , wherein the oxygen containing gas is air or oxygen enriched air. 
     
     
         11 . The process of  claim 1 , wherein the pregnant leach solution comprises copper and uranium. 
     
     
         12 . The process of  claim 1 , wherein the iron containing acidic leach solution comprises ferric ions which oxidise the ore material to dissolve copper and uranium, resulting in reduction to ferrous ions which are reoxidised to ferric ions by reaction with the oxygen containing gas. 
     
     
         13 . The process of  claim 1 , wherein the acidic heap leach is conducted in more than one stage. 
     
     
         14 . The process of  claim 1 , wherein the ripios is milled prior to flotation in process (c). 
     
     
         15 . The process of  claim 14 , wherein the ripios is milled to a particle size comprising a P80 of approximately 75 microns, preferably approximately 35 microns. 
     
     
         16 . The process of  claim 1 , wherein the ripios concentrate comprises copper containing sulphides, uranium minerals and one or more precious metals. 
     
     
         17 . The process of  claim 16 , wherein the one or more precious metals metal is gold and/or silver. 
     
     
         18 . A process for smelting a first copper concentrate that has a ratio of Cu:S below 1.4, the process comprising:
 (a) smelting a first copper concentrate that has a ratio of Cu:S below 1.4 in a first stage comprising a matte smelter to produce a matte copper product containing at least 40% copper;   (b) combining the matte copper product with a second copper concentrate to produce a feed material having a ratio of Cu:S that is higher than that of the first copper concentrate; and   (c) smelting the feed material in a second stage comprising a direct to blister furnace to produce blister copper having at least 95% copper.   
     
     
         19 . An integrated plant for use in a method for recovery of copper and uranium from an ore material as disclosed above, comprising:
 means for forming a heap of an ore material;   means for supplying an acidic leach solution and an oxygen containing gas to the heap of the ore material to form a pregnant leach solution and a ripios;   extraction equipment for extracting copper and uranium from the pregnant leach solution;   means for collecting and transferring the pregnant leach solution to the extraction equipment;   flotation equipment for use in flotation of the ripios to produce a copper concentrate and means to transfer the ripios from the heap of the ore material to the flotation equipment; and   one or more furnaces for smelting the copper concentrate to produce a smelted copper product and means to transfer the copper concentrate to the one or more furnaces.   
     
     
         20 . The integrated plant of  claim 19 , further comprising electro-refining equipment for electrolytically processing the smelted copper product to produce cathode copper.