double refractory gold ores

Enzymatic Pre-Treatment of Carbonaceous Matter in Preg ...

The bio-treatment of double refractory gold ores (DRGO) to reduce preg-robbing needs to account for the heterogeneity of the ore so as to acquire a much more complete picture of the system. To this end, the effects of ferrous ion additives on the degradation of powdered activated carbon (PAC) by cell-free spent medium (CFSM) was studied. Au(CN)2- adsorption and Raman spectrometric results ...

Technology options for processing complex and double ...

The initial results for the cyanide leach gold recoveries were very poor on a high-grade primary sulphide ore of 6.2 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.

Refractory Gold Ore Treatment Methods

At the plant of the Consolidated Murchison Co. in the Transvaal, South Africa, where a refractory high-antimony gold ore is being treated, flotation and cyanidation of the flotation concentrates and tailings are being practiced. The association of the antimony and gold is very intimate, and during 1946, while the antimony recovery amounted to ...

Microwave pretreatment of a double refractory gold ore ...

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 ...

Barrick Thiosulfate Leaching of Double Refractory Ore

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 …

NOVEL GOLD DEPORTMENT TECHNIQUE - APPLICATIONS …

A novel gold deportment technique has been developed for complex copper-gold and double refractory gold ores using state-of-the-art technology. Characterization of these ores is a challenging task due to low copper and gold grades in ores, presence of both primary and secondary copper sulfide phases

Extraction of Gold from a Low-Grade Double Refractory Gold ...

12%R. Badri and P. Zamankhan, "Sulphidic refractory gold ore pre-treatment by selective and bulk flotation methods," Advanced Powder Technology, 24 …

Microbial Pre-treatment of Double Refractory Gold Ores

In this study, microbial pre-treatment of double refractory gold ore (sample A) and concentrate (sample B) was investigated using a white-rot fungus, Tramestes versicolor (ATTC 20869). Pulp density, temperature, pH and retention times were the process variables considered.

Enhancing Gold Recovery from Nevada Double Refractory …

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). A A A A =))))) 55),, Engineering,

Increasing refractory gold production for Petropavlovsk ...

The mining of refractory ore is becoming increasingly common in Russia's numerous operational gold mines, with the process requiring additional pre-treatment prior to cyanidation for gold recovery. Enabling profitable processing of challenging ore. Close to 50% of Petropavlovsk's 21 Moz of resources and reserves are now classified as ...

US20090158893A1 - Microbial pre-treatment of double ...

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 pre-treatment of double refractory gold ores - Google Patents Microbial pre-treatment of double refractory gold ores Download PDF Info Publication number ...

ALTA MetBytes - What's Happening in Gold Ore Processing

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 arsenopyrite and also, carbonaceous black shale. Following extensive laboratory and demonstration scale testing of the Outotec

Effect of carbonaceous matter on bioleaching of Cu from ...

To overcome this problem, many researchers have challenged environmentally friendly bioprocess to maximize gold recovery from carbonaceous refractory gold ores, so-called as double refractory gold ores (DRGO) (Baron et al., 2016). In early stages, Afenya (1991) suggested several possibilities, of which bioleaching was one, but was as yet untried.

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Pretreatment of a refractory arsenopyritic gold ore using hydroxyl ion[J]. Hydrometallurgy, 2015, 153: 106–113. [15].AFENYA PM. Treatment of carbonaceous refractory gold ores[J]. Minerals Engineering, 1991, 91 (4): 1043–1055. [16].ADAMA M.D., BURGER A M. Characterization and blinding of carbonaceous preg-robbers in gold ores[J].

Improvement of gold recovery for double refractory gold ...

Gold price chart Au Why Bio-hydrometallurgy？ Low grade ore can be explored Advantages in environment, energy, safety and cost Indispensable technology for SDGs Contributions to SDGs Abbreviations D → DRGO (Double refractory gold ore) A → bio-oxidation by A. brierleyi W → Washing with1 M HCl C → CFSM treatment (Cell Free Spent Medium

Gold Two Stage Roasting - Outotec

Benefits. Our two-stage roasting plants are mainly used for treating double-refractory gold concentrates. A two-stage roasting process combines partial roasting in the first stage with dead roasting in the second stage. The first stage is used as a de-arsenifying process step in an oxygen-deficient roasting atmosphere, while the second stage ...

Double-Refractory Carbonaceous Sulfidic Gold 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 ...

Gold recovery: Effect of ozonation on refractory gold ores ...

both cases exist, the ore is said to be double refractory. Gold can also contain tellurides in rare cases; the presences of these species results in slow leaching kinetics (Ellis and Deschênes, 2016). The refractoriness of the ore can be chemical or physical (Ellis and …

SIMULTANEOUS BIOTRANSFORMATION OF CARBONACEOUS …

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 during ...

Biotechnological Approaches to Facilitate Gold Recovery ...

Double refractory gold ore (DRGO) not only include ppt levels of gold grains locked in sulfide minerals but also a problematic amount of carbonaceous matter. This causes a significant recovery loss of gold during cyanidation because of the strong affinity of the Au(CN)2− with the carbonaceous matter. Combustion decreases the carbonaceous matter content, but also emits …

Complex Orebodies Conference 2018

carbonaceous refractory gold ore (double refractory). This was a very disappointing finding but useful in that large amounts of money were not spent drilling a problematic gold ore. A small scale gravity and flotation test programme was developed to produce a concentrate with the majority of the gold.

Extraction of Gold from Refractory Gold-Bearing Ores by ...

A brief analysis of the existing and developed methods for processing refractory- and double-refractory gold raw materials showed the futility of focusing on the existing modern technological schemes, which, despite being considered effective, in many cases are fundamentally incapable of providing efficient processing of such ores [5,6,7,8,9,10,11,12,13,14,15].

refractory ore | chemistry | Britannica

Other articles where refractory ore is discussed: gold processing: Extraction from refractory ores: Many gold-bearing ores and concentrates are not readily amenable to cyanidation, owing to the presence of substances that consume the cyanide reagent before it can dissolve the gold, preferentially adsorb the gold as it dissolves (a phenomenon called preg-robbing), or completely surround the…

Microbial pre-treatment of double refractory gold ores ...

A double refractory gold ore usually contains both sulfide minerals and carbonaceous matter and results in very low gold extraction. The micro-sized gold particles are enclosed inside the mineral ...

Processing Refractory Gold - Hydrometallurgy: Leaching in ...

There are a number of factors that cause refractory behaviour in gold ores. Typically when we start investigating these ores the first step would be to undertake a mineralogical analysis that will tell you if your ore is sulphide refractory (and the grain size you are needing to target for liberation), if you have pregnant solution robbers or if you have a more complex telluride or double ...

Bio-Oxidation of a Double Refractory Gold Ore and ...

Carbonaceous sulfidic gold ores are commonly double refractory and thus require pretreatment before gold extraction. In this paper, the capacity of pre-bio-oxidation can simultaneously decompose sulfides or deactivate carbonaceous matters (CM) from a double refractory gold ore (DRGO) using pure cultures of A. ferrooxidans or L. ferrooxidans, and a mixed culture containing A. ferrooxidans and L ...

Study on the Gold Recovery of Double Refractory Gold Ore ...

Study on the Gold Recovery of Double Refractory Gold Ore Concentrate by Biological Oxidation Pretreatment. Article Preview. Abstract: In this paper, Bacterial oxidation-cyanide leaching experiments were carried out and the carbonaceous substances composition of carbonaceous gold concentrate was been studied. The elemental composition was 9.73 % ...

Barrick Gold: Design of the leach Circuit

In contrast the double refractory ores contain large amounts of carbon. This carbon must be dealt with in addition to the sulfide compounds. Similar to the sulfide ores, the gold is commonly locked away within the carbon and sulfur mineral. The issue with the carbon containing minerals is that they do not react similarly to the sulfide ores.