Hydrologic Data by Tracer Test on Situ Stope Leaching
Conventional underground mining involves the excavation and transportation of ore to the surface for processing. Tonnes of solid material is extracted from underground mining systems to produce kilograms, and sometimes only grams, of final product. Surficial processing of ore results in the disposal of most of the excavated material on the surface, with the material […]
Drilling & Blasting of Gold Heap Leach Pads
The permitting for the copper project required time beyond what was initially anticipated and stand alone gold reserves were exhausted. While leaching of the gold heaps continued, it was recognized that to continue active leaching into start up of the copper project, some actions had to be taken to increase production. The leach pads were […]
Copper Leaching and Solvent Extraction Electrowinning
The design of the DOP ensures, that proper pumping with right head-flow characteristics can be combined with a mixing tuned according to the requirements of the liquid-liquid contact to be performed. As this is not easily realized the DOP design has been backed up by Flow laboratory tests to determine the influence of a variety […]
Kinetics of Sulfuric Acid Leaching of Brass
Effect of Temperature and Acid Concentration: The effect of temperature on the leaching behavior of copper and zinc is shown by the data in Figures 1 through 4. In these experiments, leaching solutions were well stirred at 550 rpm and open to air. “Fraction Extracted” refer to that portion of the total copper and zinc that […]
Uranium Recovery by Acid Elution of Resins
An effective technique has been developed to elute ion exchange resins loaded in the carbonate leaching process for uranium recovery. The procedure involved elution with about 0.5 to 2 bed volume of 36.5 g/l. HCl, followed with 5 to 10 bed volume of acidic solution containing 3.65 g/l. HCl and 58.5 g/l. NaCl. This procedure […]
Bioleaching Chalcocite
This paper presents results of ongoing research to develop an in-situ leaching process for Michigan copper sulfide ores. The objectives of the work presented here were to determine if the copper sulfide was extractable by a bioleaching approach and to investigate how this process could be incorporated into an in-situ leaching operation. Laboratory Bioleaching Bacteria Selection […]
Dissolved Oxygen in Cyanidation with Hydrogen Peroxide
Improvement of current leaching technology was found necessary when processing ores which are more difficult to leach because they generate highly viscous, air-rejective pulps. Cyanidation of these pulps has to run at low oxygen concentrations if the conventional aeration technique with compressed air is used. Since the dissolution rate of precious metals mainly depends on […]
Heap Leach Solution Irrigation
The application of drip irrigation in Heap Leach, has been proven to be a significant improvement over conventional spray irrigation techniques. While still under evaluation, it is evident that the use of drip irrigation will increase the operating time of a heap leach during winter and may significantly reduce operating costs through reduction in reagent costs […]
Secondary Copper Converter Dust Metal Recovery using Ammoniacal Carbonate Leaching
Effective recycling or disposal of flue dusts is a continuing problem, particularly for secondary smelters treating low-grade Cu scrap. The Bureau of Mines investigated a variety of flue dust treatment approaches and demonstrated the technical feasibility of a bench-scale alkaline method that includes leaching, cementation, precipitation, and roasting. Flue dust was leached at room temperature […]
Manganese Ore Leaching by Dissolved Sulphur Dioxide
The Bureau of Mines conducted column-leaching tests on 25 domestic Mn ores to determine the feasibility of extracting Mn by in situ or heap leaching with dissolved sulfur dioxide (SO2) solutions. The ores tested were obtained from deposits in Arizona, Arkansas, California, Colorado, Maine, Minnesota, Nevada, and South Dakota. Dissolved SO2 was found to be […]