How to Improve Ball Mill Performance
Application of value engineering techniques to grinding process modelling led to the identification of two basic functions of the ball mill-classifier circuit. In terms of a specified circuit product size which is used to differentiate between “coarse” or oversize material and “fines” or undersize material, these basic functions are (a) breakage of the coarse material […]
Organic Flotation Depressant
These depressants are organic mixtures reacted with inorganic salts. They have found application for depression of oxidized pyrite, marcasite and pyrrhotite during the flotation of Cu, Cu-Zn, Cu-Pb-Zn and Pb-Zn ores. Some of these depressants have been adapted for depression of zinc during sequential copper zinc flotation. Depressants from the DS series have been successfully […]
Ultrasonic Mineral Recovery
The ultrasonic treatment unit consists of an inclined, flat bottomed metal trough, usually made of stainless steel or aluminum, with the ultrasonic transducer attached near the upper end. A typical unit would be 91.5 cm (36 inches) wide and 244 cm (96 inches) long. Figure 1 is a photograph of an ultrasonic treatment unit being […]
Carbon Strip Circuit Control Scale
Carbon strip circuits present a particularly challenging scale inhibition problem. Many of the factors that tend to promote scaling are present in these systems. For example, carbon strip circuits are run at high temperatures, high pH levels, and require long batch cycle times. Tortuous paths are encountered by the strip solution circulating through heat exchangers, […]
Environmental Auditing Procedures in Mining
Environmental audits can serve many purposes. One way in which an audit may be used is to assess an operating company’s compliance with environmental laws while the mine is in operation. Information derived from an audit of this type can guide management toward making immediate adjustments to correct procedural problems before they create major environmental […]
Ultimate Pit Limit Design
In open pit mine planning, the design of the most profitable ultimate pit limit is a prerequisite to developing a feasible mining sequence. Presently, the design of an ultimate pit is achieved through a computer program in most of the mining companies. 3-D block model is commonly applied to represent geologic and economic information of […]
How Temperature Affect Grinding Efficiency
The effects of temperature on autogenous grinding can be immediately divided into rheological effects and mechanical effects. The rheological effects are a result of the substantial increase in the viscosity of water as the freezing point is approached. The change in apparent slurry viscosity which results from changing temperature is shown in Figure 1. As […]
Compacted Clay Liners
Soils used to construct compacted permeability barriers such as liners for solid and liquid waste landfills and lagoons must be carefully evaluated and designed to maintain their integrity in preventing seepage of pollutants off site. The practice of using any on-site soil without testing its hydraulic and flexural properties is dangerous. Silts and fine sandy […]
Sulfate Ion & Anionic Surfactants
The U.S. Bureau of Mines is investigating surfactants added to water sprays to enhance the control of dust during coal mining operations. The objective of the present work was to establish the general applicability of adding sulfate ion to anionic surfactant solutions in order to improve wetting action. This was pursued through laboratory wettability testing […]
Heap Leach Pad Liner: Differential Settlement
The maximum settlement (S) of the soil subbase occurs at the center of the wetted soil column. There would be little to no settlement along the dry edges of the column. The total settlement can be estimated by multiplying the percent soluble minerals times the controlling depth, DI. As the liner deflects to fill the […]