To complicate matters further, these ore bodies are often refractory, where the gold is locked within sulphide minerals; or double refractory, in which gold is locked within sulphide minerals and pregrobbing due to the presence of organic carbon. These must be pretreated ahead of leaching.

and pyritesolid solution gold atomically distributed in the crystal structure sulphide minerals •Naturally occurring active carbon which results in pregrobbing . Gold may be exposed to cyanide solution for leaching but recovery is inhibited by the gold getting adsorbed onto carbon •Double refractory are concentrates or ores in which gold is

A notable example of such a doublerefractory carbonaceous sulfide ore is at Barrick’s Goldstrike Mine where gold occurs in pyrite in refractory sulfide ore and doublerefractory sulfidic/ carbonaceous ore. These ores are pretreated by autoclave and roaster prior to cyanide leaching (Thomas et al., 2000; Wickens et al., 2003). In the Jinya

Abstract Double refractory gold ores, such as Barrick’s Goldstrike ore, contain both pyrite and carbonaceous matter and the latter results in the loss of gold from solution during cyanide leaching. One possible remedy is to roast the ore and thus oxidize the pyrite and remove the organic carbon. In this research, microwave roasting of a double refractory gold ore was investigated as an ...

Chapter 45. Processing of HighSilver Gold Ores; Chapter 46. Recovery of Gold as ByProduct from the BaseMetals Industries; Chapter 47. Extraction of Gold from Platinum Group Metal Ores; Refractory Ores; Chapter 48. Refractory Sulfide OresCase Studies; Chapter 49. PregRobbing Gold Ores; Chapter 50. DoubleRefractory Carbonaceous Sulfidic ...

Double refractory gold ores, such as Barrick’s Goldstrike ore, contain both pyrite and carbonaceous matter and the latter results in the loss of gold from solution during cyanide leaching. One possible remedy is to roast the ore and thus oxidize the pyrite and remove the organic carbon.

The present invention is directed to recovery of gold from refractory and double refractory ores using a fungal agent and/or culture media. US20090158893A1 Microbial pretreatment of double refractory gold ores Google Patents Microbial pretreatment of double refractory gold ores Download PDF Info Publication number ...

Metallurgical ContentGold Leaching Processing of Arsenic OreMispickel (Arsenopyrite: FeAsS).6Leaching and Recovering Gold from Antimony MineralsStibnite (Antimony Sulphide, Sb2S2)Telluride Gold Ore ProcessingSolubility of TelluridesGold Extraction from Carbonaceous OreList Gold Refractory Process Methods Where gold is associated with arsenic, antimony, tellurium, and …

Sulfides and carbonaceous matter in double refractory gold ore (DRGO) were biotreated sequentially using an ironoxidizing archaeon Acidianus brierleyi followed by lignin peroxidasedominating crude enzymes released from the whiterot fungus Phanerochaete chrysosporium to significantly improve gold …

A novel gold deportment technique has been developed for complex coppergold and double refractory gold ores using stateoftheart technology. Characterization of these ores is a challenging task due to low copper and gold grades in ores…

Ores where gold is associated with sulfides and with high carbonaceous matter content are considered double refractory. Ores in the Carlin Trend District are characterized by the presence of submicroscopic gold (invisible gold…

Double refractory ores present a unique challenge to the traditional method of gold recovery in mining. Double refractory ores are ores that contain sulfides and carbons, as opposed to single refractory ores which contain only sulfides. In general, the cyanide solution pulls the gold out of the ore …

In the case of Goldstrike, this was a doublerefractory ore combining sulphideoccluded gold with pregrobbing carbonaceous material that rendered the ore unsuitable for conventional cyanide leaching …

Refractory gold ores are those that do not yield high gold recoveries in conventional cyanideleaching circuits, even when the ore is finely ground. The cause of low gold recoveries can be either through the presence of naturally occurring ‘preg robbing’ carbonaceous materials or gold physically ‘locked’ in sulphide minerals. ...

A twostage bacterial pretreatment process for double refractory gold ores Amankwah a,*, W.T. Yen a, Ramsay b a Mining Engineering Department, Queen’s University, Kingston, Ontario, Canada K7L 3N6 b Chemical Engineering Department, Queen’s University, Kingston, Ontario, Canada K7L 3N6 Received 7 April 2004; accepted 11 May 2004 Abstract Double refractory gold …

Chapter 45. Processing of HighSilver Gold Ores; Chapter 46. Recovery of Gold as ByProduct from the BaseMetals Industries; Chapter 47. Extraction of Gold from Platinum Group Metal Ores; Refractory Ores; Chapter 48. Refractory Sulfide OresCase Studies; Chapter 49. PregRobbing Gold Ores; Chapter 50. DoubleRefractory …

of double refractory gold ores and concentrates. Currently numerous studies are in progress to further improve upon the efficiency of the bacterial process and to investigate the potential of other microorganisms. In this study, microbial pretreatment of double refractory gold ore (sample A) and

Highly refractory gold mineralisation – including double refractory ores, gold associated with both sulphide and carbonaceous mineralogy. Low to middletier resources that target a gold production of less than 150,000 oz per annum.

The present invention is directed to recovery of gold from refractory and double refractory ores using a fungal agent and/or culture media. US20090158893A1 Microbial pretreatment of double refractory gold ores Google Patents Microbial pretreatment of double refractory gold ores …

The initial results for the cyanide leach gold recoveries were very poor on a highgrade primary sulphide ore of g/t Au with no silver. Subsequent mineralogy showed the ore to be a characteristic pyrite, carbonaceous refractory gold ore (double refractory). This was a very disappointing finding. A small scale gravity and flotation test programme...

Method to improve recovery of gold from double refractory gold ores Download PDF Info Publication number US8262768B2. US8262768B2 US12/208,985 US20898508A US8262768B2 US 8262768 B2 US8262768 B2 US 8262768B2 US 20898508 A US20898508 A US 20898508A US 8262768 B2 US8262768 B2 US 8262768B2 Authority US United States Prior art keywords

Jan 01, 2016· Ores where gold is associated with sulfides and with high carbonaceous matter content are considered double refractory. Ores in the Carlin Trend District are characterized by the presence of submicroscopic gold (invisible gold) finely disseminated within a …

Double refractory gold ores (DRGO) contain metal sulfides that encapsulate gold and prevent its dissolution by cyanide, and carbonaceous matter (CM) that adsorbs gold cyanide complex. Pretreatment is therefore required to decompose the sulfides and liberate gold before cyanidation, and to deactivate CM and prevent it from adsorbing gold …

of refractory and double refractory gold ores. Commonly, in these types of ores, the gold is associated with sulphide minerals. The presence of sulphides can affect gold recovery via cyanidation due to encapsulation or passivation of the gold, thereby increasing reagent consumption. In the case of double refractory ores, gold …

Enhancing Gold Recovery from Nevada Double Refractory Gold Ores using a Novel Dual Bubble Generator by Jian Huang A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Chemical Engineering ... gold ores…

double refractory gold or es", Minerals . Engineering, Vol. 18, ... Refractory gold ores are those that do not yield high gold recoveries in conventional cyanide leaching circuits, even when the ...

double refractory ore has been achieved at Nordgold’s Suzdal mine in Kazakhstan which treats double refractory ore with both visible and invisible gold hosted in sulphide associations of pyrite and …