Gold Precipitation Test
The following method of testing the precipitation of gold in pregnant cyanide solutions has been adopted by the Ore Dressing and Metallurgical Laboratories, Bureau of Mines, Ottawa. The apparatus consists of three Erlenmeyer flasks of 3000-cc capacity (see Fig. 5). Flask A is for evacuation of air from the pregnant solution, flask B is for precipitation, and […]
Gold Refining Process
To present the essential points of all methods of gold refining commonly practised, as well as those of historic interest,” was the author’s purpose in this volume. The fifteen chapters of which the book consists deal with the Simpler Methods of Early Days; Amalgamation Process; Refining with Oxidising and Chloridising Agents; Sulphur Refining; Refining with […]
AARL Carbon Stripping System Operation: Elution & Electrowinning
The Anglo American Research Laboratories AARL carbon stripping system used in this EXAMPLE has two definite advantages when compared with its most common counterpart, the Zadra system. It is much less expensive to operate and it produces a cleaner stripped carbon. It is however very reliant upon the availability of an abundant supply of good quality water […]
Carbon Fouling & Deactivation
Fouling of carbon with associated deactivation is fairly rapid in CIP circuits. Acid washing and elution only partially reactivate carbon and so for its repeated use, thermal reactivation after each loading is essential. Reactivation kilns are basically of two types; rotary kilns and vertical kilns. The use of rotary kilns is widespread but generally they […]
Preparing Cathode Wool for Smelting
The cathode wool is changed weekly or more often if necessary. Electrowin day is however the cut off point. First thing on Monday morning a sample should be taken from the cell for assay and then the eluate solution diverted to the spare cell. Removing the Wool Dump the solution in the cell by opening the […]
Intensive Cyanidation
The upgrading of gravity concentrate for smelting purposes by use of intensive cyanidation is still in the experimental stage. It involves the leaching out of the gold into solution, using a strong cyanide mix, and then the electrowinning of that solution so as to recover the gold on the steel wool cathodes. This system is […]
Roasting Arsenic Gold Ores and Concentrates
Roasting Arsenic Gold Ore
Effect of Impurities on Gold Slimes Refining Process
The richer the slimes are in gold the easier it is to treat them. In the majority of cyanide plants not enough care is taken to eliminate mechanical impurities before the solutions pass into the zinc boxes. No silica or insoluble substance should be allowed to pass into the precipitating box. Further, some salts are […]
Purify Gold Slimes to Make Bullion Gold Bar by Nitre Cake Refining Method
When carrying out experiments on the best methods of cleaning up or obtaining bars of bullion from gold slimes several points have to be considered. Large losses sometimes occur in ordinary practice in the drying and roasting of such finely divided material; losses occur through the feeding of such fine dust into the melting pots, […]
Gold Slimes Refining & Acid Treatment of Precipitates
Strong Nitric Acid Many attempts were made to further purify bullion slimes before smelting. The impurities present, as well as the gold, are in a state of fine division, and, therefore, adapted for solution. It might be assumed that copper and silver present could be removed by means of nitric acid. This acid was tried […]