Heap leach operation

Determining the effects of impurity build-up on recycle of the extraction raffinate to the heap leaching operation, and on recycle in the extraction and electrowinning circuits ... 

Figure 6.3 A typical heap-leach operation. Source-. [69].

Heap-leach operations are typically zero-discharge facilities [69]. A typical heap leach operation is shown in Figure 6.3. A weak cyanide solution is sprayed over the stacked ore and pregnant solution flows to a lined collection ditch, then to a pregnant solution pond, then to a recovery plant with carbon... 

Sanyati is a copper mine located in Zimbabwe. The project was developed during 1998 with a flowsheet for zinc SX and EW, similar to the one described above. The feed was a solution containing copper and zinc. This solution was a PLS from an existing copper heap leaching operation, but because of the concentration of zinc in the ore, the zinc concentration in the copper PLS was building up to levels that made recovery of the zinc by the MZP feasible and profitable. 

In the most common hydrometallurgical process for zinc manufacturing, the ore is leached with sulfuric acid to extract the lead/zinc. These processes can operate at atmospheric pressure or as pressure leach circuits. Lead/zinc is recovered from solution by electrowinning, a process similar to electrolytic refining. The process most commonly used for low-grade deposits is heap leaching. Imperial smelting is also used for zinc ores. 

Gold recovery Operation of carbon in leach, carbon in pulp, and heap leach circuits Recovery of gold from tailings dissolved in sodium cyanide... 

The present description pertaining to copper refers to solvent extraction of copper at the Bluebird Mine, Miami. When the plant became operational in the first quarter of 1968 it used L1X 64, but L1X 64N was introduced in to its operation from late 1968. The ore consists of the oxidized minerals, chrysocolla and lesser amounts of azurite and malachite. A heap leaching process is adopted for this copper resource. Heap-leached copper solution is subjected to solvent extraction operation, the extractant being a solution of 7-8% L1X 64N incorporated in kerosene diluent. The extraction process flowsheet is shown in Figure 5.20. The extraction equilibrium diagram portrayed in Figure 5.21 (A) shows the condi-... 

The Pacific Northwest National Laboratories estimated that the total cost estimate for batch leaching of contaminated soils is 30 to 500 per ton of treated soil and for heap leaching of contaminated soils is 10 to 150 per ton of treated soil. These costs include excavation, capital, and operating and maintenance costs. This estimate is based on costs for leaching of precious metals from ores in the mining industry (D18769D, p. 5). 

The Biocat II technology is an improvement of the Biocat process (U.S. Patent 5,076,927), which treats acid mine drainage and heap leach effluents. The improvements were made under a Phase I Small Business Innovation Research (SBIR) grant funded by the Defense Advanced Research Projects Agency, a component of the U.S. Department of Defense (D10362Y, p. 4). If adequate concentrations of sulfuric acid are not present, additional acid may be required to operate the process. 

Andersen, J.E. and Allman, M.B., 1968. Some operational aspects of heap leaching at Rum Jungle. Proc. Aust. Inst. Min. Metal., 225 27—31. 

Breitenbach, A. J. (2004), Improvement in slope stability performance of lined heap leach pads from design to operation and closure, GFR Engineering Solutk>ns,ll ). 

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