PROCÉDÉ DE CYANURATION POUR RÉCUPÉRATION DE .. ), containing concentrations of cyanide between 50 and 15, mg/L. The. Get this from a library! Effet de la granulométrie sur la cyanuration de l'or. [Jessica Egan]. Les études existantes de la cinétique de cyanuration du minerai d'or démontrent une diversité significative des paramètres estimés de la.
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Ligne complete de cyanuration d or
Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted.
Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. The solid containing the basic copper salt may be subjected to a subsequent acid leaching step, typically at atmospheric pressure, to leach the basic copper salt into solution, thereby obtaining a copper solution which is treated, along with the pressure oxidation solution should it cyanuration de l or recoverable amounts of copper in solution to copper solvent extraction and electrowinning to produce cyanuration de l or copper.
Some of these modifications which pertain particularly to the recovery of precious metals are described in applicant's US Patent 5, the ' patentthe entire contents of which is incorporated herein by reference.
It is significantly different from the process as described in the ' patent and has the advantage of being simpler than the earlier process with overall lower costs. The ore must first be crushed and ground to allow cyanuration de l or to be suspended by agitation.
cyanuration de l or Several types of agitation have been used including mechanical agitation and air agitation pachucas. Agitated tanks are used for ores that are relatively high grade in gold or silver, as this method produces better recovery than heap leaching, albeit at higher operating and capital cost.
Sparging of air can be done to increase flow of oxygen into the slurry, but that generally increases the loss of expensive hydrogen cyanide into the offgas.
Sparging of pure oxygen into the slurry is also known, as is the addition of other reagents such as liquid hydrogen peroxide to accelerate leaching. This low cost process is used for low grade ores and takes place over a longer period time of time, generally several months. Air ingress to the heaps by natural processes such as convection is generally sufficient cyanuration de l or cyanidation to proceed at an acceptable rate.
Cyanide leaching is believed to involve oxygen as a reagent, as in the familiar Elsner equation: Perhaps this is because the obvious advantages of the improved leaching kinetics may be outweighed by the higher capital costs for such a process, with normal gold and cyanuration de l or ores.
These rather unusual feed materials required much lower pH conditions than normal, i. Under these low pH conditions cyanide consumption would be very high, using conventional cyanidation in open tanks at ambient pressure, because of the excessive volatilization of HCN gas, which increases rapidly with decreasing pH, and also because of the high levels of cyanide needed with this unusual feed material.
The process developed at Consolidated Murchison resulted in a commercial plant which satisfactorily resolved these difficulties.
Effet de la granulométrie sur la cyanuration de l'or
In the present invention pressure cyanidation for this feed material is designed to limit thiocyanate production by operating at unusually low retention times. The process of the present invention is not limited to low pH, and the normal pH range is 10 - 11, but is not limited to this range.
The present invention therefore overcomes a cyanuration de l or problem than is dealt with by the Consolidated Murchison process.
It was built in Colorado in the 's evidently, but apparently closed down a few years later. This is different from the present invention, in which pressure oxidation cyanuration de l or leaching of base metals, such cyanuration de l or copper, if present, is effected first in a separate operation, and the residue from this operation is then subsequently treated for precious metals recovery, as will be described in more detail below.
Such ores typically contain 0. Rarely is the combined gold and silver content so low as to be negligible. The precious metals follow the copper through the various steps of matte smelting and converting to blister copper.
The blister cyanuration de l or is then usually refined by electrolysis to remove impurities and during this refining process precious metals report almost quantitatively to the refinery anode slime, which has a low mass, typically only a few kg per tonne of Cu metal.
The anode slime therefore has a high concentration of the precious metals relative to the original copper concentrate fed to the smelter, e.
Effet de la granulométrie sur la cyanuration de l'or
Such low mass and high concentrations of gold and silver in the slime lead to low processing costs for final recovery and refining of the precious metals. Cyanuration de l or such a large mass to recover only small amounts of precious metals at low cost specifically a cost that is low in comparison to the value of the precious metal content in the residue is clearly a difficult process to design.
Often the cyanide consumptions are less than 0. The elemental sulphur also reacts partly with cyanide solutions leading to the formation of thiocyanate compounds, such as NaSCN.