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Regeneration of Activated Carbon used for Recovery of Gold

The process of treating granular activated carbon for return to service in the recovery of gold in Carbon in Pulp and Carbon in Leach circuits has been investigated. Carbons from four U.S.A. mines, one Canadian mine and one South African mine were characterized before and after regeneration. The use of thermal gravimetric analyses demonstrated the … Read more

Zero Order Production of Fines in Grinding

The phenomenon of zero order production of fines associated with the batch comminution of monosize feeds in tumbling mills has been examined in the context of the size discretized population balance model. It has been shown that the model admits zero order production kinetics only in an approximate sense. The necessary and sufficient conditions for … Read more

Portable Crushing

Decreasing ore grades and increasing labor and material costs have seriously eroded the economic vitality of many mining operations. Coupled with global economic stagnation and recession in the early 1980’s, these conditions have forced re-evaluation of operating strategies and methodologies with the objective of remaining competitive in a world marketplace. An important factor in system … Read more

Placer Sampling and Reserve Estimation

Placer Sampling One of the most difficult tasks associated with placer mining is the sampling of the deposit. More placer projects have failed due to inaccurate assessment of the reserves than to any other reason. Within the realm of placers, those containing valuable minerals with a high unit Value are more difficult to sample than … Read more

Things to do to Improve Metallurgical Performance

Alternative methods to restrict and eliminate the detrimental effect of critical size material on the performance of an autogenous mill. Palabora has a unique orebody in that it contains most of the valuable minerals known, but unfortunately also some gangue minerals which have a major influence on the milling rate. The two gangue minerals having … Read more

Magnetic Separators to Improve Mineral Cleaning

The strongest magnetic roll separator available on the market enhances certain industrial minerals purity to levels not reached previously. Exceptionally strong forces can also be utilized for processing relatively fine particles at feed rates several times greater than for prior art electromagnetic induced roll separators. Since the unique machine does not work with an air-gap, … Read more

Magnetic Separation of Fine Mineral Sulphides

The separation of fine sulfides becomes increasingly difficult at fine particle sizes. Potential fine size separation methods are froth flotation and magnetic separation. The mineral sulfides, with the exception of pyrrhotite, are either weakly paramagnetic (e.g. chalcopyrite) or diamagnetic (e.g. molybdenite). Those which are paramagnetic can only be separated using high-gradient magnetic separation (hgms) at … Read more

Kaolin Tailings Ponds

Kaolin tailings ponds play an important role in reclamation of land and water. Discharges impounded from kaolin plants include oversize fractions consisting of coarse kaolin, mica, quartz as well as magnetically extracted contaminents, acid filtrates, and plant washdown streams. Tailing ponds perform an essential function in sedimentation of particulates, blending and reoxygenation of liquid waste, … Read more

Indirect Drying Filter Cake

The Thermal Disc is the only transport type dryer which can handle flotation, thickener underflow and pond recovery feed streams without the addition of a coarse fraction. The principle of operation differs from all other types of indirect dryers in that it is a volumetric displacement apparatus rather than first in first out. An operating … Read more

In Pit Crushing and Conveying Systems

Belt conveyor systems, long the standard transportation technique in soft-rock open-pit applications, are encountering growing interest in the hard-rock open-pit sector as economic factors force companies to seek an alternative to costly truck haulage. A general review of mine conveyor systems is followed by detailed analysis of the mobile and semi-mobile in-pit crushing plant essential … Read more