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Cyanide Biodegradation

Management of mine drainage and mineral processing waste systems is a serious problem that could have major impacts on the U. S. mineral industry. Federal legislation (established by the Superfund Amendments and Reauthorization Act of 1986) provides that preferred remedial actions are those treatments that permanently and significantly reduce the volume, toxicity, or mobility of … Read more

Pebble Crushing Circuit Design

The design of a pebble crushing circuit as an integral part of a North American style primary autogenous or semi- autogenous grinding circuit presents certain challenges to the process design engineer. Initially, the process requirement for pebble crushing has to be determined as part of: the design of a new plant the relief of a … Read more

Mechanism of Sulfur Oxidation in Pyrite

The Mechanism of Sulfur Oxidation in Pyrite is base on what is generally believed as anodic oxidation of pyrite occurs according to the reactions to form S° and SO4=. FeS2 = Fe++ + 2 S° + 2 e-…………………………………………………………………….(1) FeS2 + 8 H2O = Fe+++ + 2 SO4= + 16 H+ + 15 e-…………………………………(2) Pyrite crystals were … Read more

Magnetic Reagents

The behavior of fine mineral particles in a slurry is difficult to control, presenting a serious problem in many processes. At fine particle sizes, gravitational force is weak. Electrostatic force, although strong in dry conditions, can rarely be applied for particles in an aqueous slurry. The applications for using magnetic force are limited because most … Read more

Dry Gravity Separation

The basic principle of this separation method was already defined in the middle of the nineteenth century. However, a change over for the treatment of minerals has followed from the construction of proper machines i.e. airjigs and airtables as late as in the twenties and thirties of this century. The main application of this technology … Read more

Peroxide Leaching of Gold Silver Sulfide Flotation Concentrate

The alternatives considered for accelerating the concentrate leach kinetics were addition of air or oxygen, and Degussa Corporation’s peroxide-assisted leaching (PAL) process. Air addition was tried, but only produced a voluminous froth which overflowed the leach tank, because of the presence of residual concentrations of flotation reagents. Therefore, addition of oxygen was ruled out because … Read more

Chemoremediation of Acid Mine Drainage

The chemical alteration of water by acid mine drainage begins with the exposure to the atmosphere of pyrite associated with coal during the mining process. The exposed sulfide minerals, which are relatively insoluble in their original state, are converted by oxidation to soluble sulfuric acid, which in turn dissolves other minerals containing manganese, aluminium and … Read more

Sediment Compressibility in Thickening of Flocculated Suspensions

Polymeric flocculants are widely used to enhance particle sedimentation in the application of thickening processes to slurry dewatering. When properly applied, these flocculants promote the formation of large flocs which settle rapidly and provide for effective water clarification through the efficient capture of fine, suspended solids. However, the flocs formed are generally of very low … Read more

Calculation of Mineral Liberation in a Continuously Operating Ball Mill

The calculation of the liberation spectrum in the product from a continuously operating ball mill is both important and difficult The liberation spectrum depends on the mineralogical texture of the ore from which the mill feed derives and also on the processing steps through which portions of the feed have passed prior to milling. These … Read more