Principles of Gold Cyanidation Explained
What is commonly known as the Cyanide Process has for its object the commercially profitable recovery of gold and silver from their ores, and this is accomplished by the solvent action of an alkaline cyanide solution on the precious metals. The first step in the Cyanidation process is to mill or grind the ore to […]
Chemistry of Cyanidation of Gold & Silver
The usual reaction given for the dissolution of gold and metallic silver in cyanide solution is known as Elsner’s equation. 2Au + 4KCN + O + H20 = 2KAu(CN)2 +2KOH Silver sulphide, the form in which silver most commonly occurs in its ores, involves a different set of reactions, which are usually expressed thus: First […]
Compare NaCN Sodium Cyanide VS KCN Potassium Cyanide
There is probably no potassium cyanide now made for commercial purposes. With the development of the cyanide process the custom grew up, for economic reasons, of manufacturing what was called a “double salt” composed of potassium and sodium cyanides in varying proportions. This material was compounded so as to have a cyanogen content of 98% […]
List Sources of Cyanide Loss
Below is a list of things/factor which can cause cyanide loses in the leach process: The Precious Metals The amount of cyanide that combines with the gold in an average ore is negligible, but with silver it is different owing to the much larger quantity of metal that has to be dealt with to produce […]
Gold Circuit Carbon Sampling for Inventory and Movement
Metallurgical performance of gold and silver mineral processing flowsheets is typically evaluated using assay balance and production balance techniques. With assay balance the mill feed, tailings, and some intermediate streams are sampled and assayed. Gold circuit performance can then be evaluated using mass balance techniques. Unsteady plant conditions and difficulties in sampling and measuring moving streams are some problems with this method. Production balance measures […]
Mineral Processing Operating Cost Estimate of Ore Treatment
Only where a group of mines operates in a single district are costs comparable and then only with reservations. In general, cost systems are fairly uniform, yet in studying costs of a number of plants it is noticeable that in some cases there is a tendency to omit certain operations which are proper charges against […]
Manganese Silver Ore Treatment Method
The present is to discuss some of the current silver-treatment plants and also reviews briefly some of the older practices in important silver-mining areas since closed down. The greater part of the world’s production of silver is derived from the refining of the base metals, particularly lead ores, and complex ores of lead, copper, antimony, and […]
Handling Waste Cyanide Solution
Tailings pulp carrying traces of cyanide and the discard of barren solutions in some cases constitutes a hazard to both humans and animals, and methods have been devised for destroying the contained cyanide. A recent paper “The Treatment of Cyanide Wastes”by Chlorination by J. G. Dobson published in the Sewage Works J., November, 1947, discusses […]
Gold Chlorination Processes & Methods
In Liddell’s Handbook of Nonferrous Metallurgy, Vol. 2, 1945, there is to be found a very complete account of the uses of chlorine as applied to the recovery of gold and silver, in Chlorination Processes & Methods. Introducing the chapter entitled “Chlorine Metallurgical Processes” Liddell says: Chlorine as a metallurgical agent appears to have lost ground […]
Bromocyanide Process
Bromo salts are a mixture of 57 per cent sodium bromide, NaBr, and 43 per cent sodium bromate, NaBrO3, in the form of light-gray, light- yellow, or reddish-brown crystals or powder. The use of bromo salts for treating a telluride concentrate in the Wright- Hargreaves plant at Kirkland Lake is described by J. T. Willey […]