Ammonia Gold Dissolution Leaching
Processes for gold extraction usually depend on how gold is associated with its environment. Although cyanide leaching remains the overwhelming option for the treatment of gold ores, because of its economy and simplicity, it suffers from certain inherent drawbacks such as toxicity, low leaching rate and its inefficiency of treating certain classes of refractory ores. […]
High Pressure Roll Grinding for Copper Heap Leaching
Technology improvements in copper mining operations have been the key factor for increasing productivity. Beyond dump leaching, the industry will increasingly use various heap leach techniques in SX-EW operations in the coming years in order to optimize recovery and maintain low production costs. They include: Finer comminution followed by agglomeration. Finer comminution followed by coarse […]
Effect of Water Chemistry on Flotation Performance
The two size reduction/froth flotation interactions described in this paper are strongly related to optimally using the inherent electrochemical surface rearrangements that occur on selected sulfide minerals, e. g. chalcopyrite, molybdenite, pentlandite, etc. Based on data generated in numerous fundamental studies, it is not surprising that utilizing the electrochemical transformations that occur with grinding could […]
Ceramic from Ilmenite & Zircon
The direct conversion of mineral concentrates into useful ceramic materials, without several intermediate processes, is of great interest to the materials community. Recently there has been increased interest in producing ceramic powders with very small sizes (in the order of nanometers) starting with mineral precursor. Thermal plasma processing of mineral concentrates may be used to […]
Convert Valve and Elbow to Equivalent Length of Pipe
The 150mm (6″) elbows have a S value of 1.7 per Table II. This multiplied by 10 and 6″(150 mm) gives an equivalent length of straight pipe of 102′(31m).
Protection against Rockfall by Steel Wire Rope Safety Net Systems
Wire Rope Net Rockfall Barriers A rockfall protection system with the appropriate strength characteristics and height can be designed. Wire rope net rockfall protection barriers of varying designs have been engineered with the proven ability to withstand impact kinetic energies ranging from 81 kJ (30 ft-tons) for the simplest of designs, to a maximum of […]
Remove Micronized Magnetite from Coal
The micronized-magnetite coal cleaning technology is based on widely used conventional dense-medium cyclone applications, in that it utilizes a finely ground magnetite/water suspension as a separating medium for cleaning fine coal, by density, in a cyclone. However, the micronized-magnetite cleaning technology differs from conventional systems in several ways: It utilizes significantly finer magnetite (about 5 […]
Selecting Centrifugal Slurry Pump Based
Making a sketch of the pump system, including dimensions, is very helpful in determining the static heads, friction heads, etc. After determining the top size of the solids and solid size distribution by the results of a screen analysis of the material, we can select the materials to be used in the construction of the pump. […]
Gold Extraction in Carbonaceous Ore using Thiosulfate
The U. S. Bureau of Mines has been investigating the application of thiosulfate to recover gold directly from low grade refractory carbonaceous ores for the past four years. Statistical experimental methods were used to determine the effects of various leaching parameters on both gold extraction and thiosulfate consumption. Seven variables were investigated, including thiosulfate, copper, […]
Flotation Hydrodynamic
The Bureau of Mines conducted research on the flotation hydrodynamics of fine particle flotation to improve the flotation efficiency in our domestic minerals industry. The turbulent fluid velocity profile was measured in various flotation cells at different levels of dissipation energy. The importance of dissipation energy and bubble size within the flotation cells for the […]