mainly about the refractory gold leaching easily through arsenic removal to expose gold, changing the composition, physic-chemical and electro-chemical properties of the ore Currently, there are four main methods of pretreatments of refractory gold ores with As Pretreatment options for deal-ing with refractory gold ores are illustrated in Fig ....

refractory gold pretreatment 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...

Many of the gold deposits contain finely disseminated gold in iron sulfide minerals such as pyrite and arsenopy- rite Such deposits are called refractory gold ores due to the encapsulation of fine particles of gold in the ore host A clear boundary between refractory and non-refractory ore in terms of gold recovery is not well defined, but...

Pretreatment of Refractory Gold Ores Using Cell-Free Extracts of P chrysosporium A Preliminary Study p427 Recovery of Zinc during the Pre-Treatment of a Refractory Gold-Bearing Ore p431 Substrate Utilisation and Chalcopyrite Concentrate Bioleaching at 60 176 C in the Presence of Nitrate ....

The characteristics of refractory gold ores and the principles of selecting pretreatment program are introducedThe development and new trends of the methods of roast,pressure oxidation and bio oxidation in recent years are summarized...

The present application claims the benefits of US Provisional Application Ser Nos 60/990,805, filed Nov 28, 2007, and 61/088,928, filed Aug 14, 2008, both entitled Microbial Pre-Treatment of Double Refractory Gold Ores , both of which are incorporated herein by this reference in their entireti...

most common pre-treatment options, and speaks to some companies that offer or use the processes A refractory gold ore is gold-containing ore that is resistant to recovery by direct cyanidation and carbon adsorption process More specifically, it is an ore that has a gold recovery rate of less than 80 when direct cyanidation is applied to it...

With regards to the application of microwaves to refractory gold ores, Haque, 1987a, Haque, 1987b has studied the microwave pretreatment of refractory sulphidic ores and achieved gold extractions of over 98 However, there is no information published on the microwave processing of the double refractory gold or...

ALKALINE OXIDATIVE LEACHING OF GOLD-BEARING ARSENOPYRITE ORES By P Bhakta,1 J W Langhans, Jr,1 and K P V Lei2 ABS rRACT The US Bureau of Mines developed an alkaline oxidative pretreatment leaching procedure to increase the recovery of gold from arsenopyrite FeAsS or The best solution compositions for...

A study was conducted to examine how pretreatment of carbon-bearing gold ores with chlorine enhances gold recovery by cyanidation It is hypothesized that metal species including iron and copper dissolved during chlorination adsorb on the carbon surface hindering the adsorption of dissolved gold To test the hypothesis, samples of several sulfide minerals were subjected to....

For extraction of gold from the refractory ores in which gold is surrounded by sul-fide minerals, oxidative pretreatment of the ore is essential to oxidize the sulfides and expose gold Pyrometallurgical oxidation by roasting is encountered with environmen-tal limitations thus hydrometallurgical methods are preferred These methods include...

Refractory gold ores have increasingly been the main source of gold production with the exhaustion of amenable gold or Of the 2630 tons of total world gold production in 2011, about 25 was produced from refractory gold deposits, and of the top 20 gold operations in 2011, eight were processing refractory ores...

Refractory gold ores present a number of problems to the gold producer Much has been written about the suitability of particular pretreatment processes for specific gold or We at Hazen Research have had the opportunity to participate in the development and application of a number of gold ore processes and to review others...

Figure 5 - Refractory Ore Pretreatment Options In order to choose a pretreatment option for a refractory ore, the main concern is attaining a solution which succeeds in preparing the ore for cyanidation, whilst remaining economically feasible Mill Sizing The ore throughput rate of a mill is largely dependent on the mining production rate...

Acid pressure oxidation is generally believed to be the most effective pretreatment for refractory sulfide gold ores and concentrates, although it is ineffective for some or For such ores and concentrates usually those containing both carbonaceous and sulfide materials , roasting remains the most effective pretreatment before cyanidation...

In this work ozonization was studied as pretreatment for two Mexican refractory ores in order to increase the gold and silver extraction Two methods for contacting ozone with the mineral were studied indirect and direct...

Pre-treatment of a refractory gold sulfide ore by means of - SciELO Abstract Cyanidation is a relatively simple and cheap technology to treat Biological oxidation biooxidation as pre-treatment of refractory gold ores is based on the Before inoculation, sulfuric acid consumption was 675 g H2SO4/kg ore...

Developments in the pretreatment of refractory gold minerals by nitric acid D-X LI College of Environmental Science and Engineering, China The paper covers many literature reports of processes using nitrogenous species as an oxidant for processing refractory gold ores, especially development in the pretreatment of refractory gold...

This study deals with provided that gold is coarse enough to the alkaline sulfide leaching as an Gold ores are commonly classi- be physically and economically liber- alternative pretreatment method fied as free-milling and refractory for antimonial refractory gold and ated ores based on the metallurgical per- silver bearing or...

Sulphidic refractory gold ore pre-treatment by selective and bulk flotation methods , In this paper, the selective and bulk flotation methods are considered as primary sulphidic refractory gold ore pre-treating options The results show that it is impractical to remove arsenic As and antimony Sb from downstream processes by using ....

Jun 24, 2017 0183 32 The problem of the refractory nature of gold bearing arsenide ores is described The basic principle, characteristics and application of pretreatment technique of arsenic-bearing gold ores are presented in this paper Several different classes of process options for pretreating refractory ores ,...

Gold ores are considered refractory if gold extractions from a conventional cyanidation process are less than 80 even after fine grinding 1 Arsenic-bearing refractory gold ore has stones extremely difficult to deal with In the stones, gold is locked up in arsenic mineral matrix as the form of microscopic or submicroscopic lattice...

Also, grinding the ore to an extremely fine particle size can liberate gold encapulsated in sulfid SGS has very extensive experience with all the unit operations involved in the processing of refractory gold ores, and in selecting the optimum flowsheet for a particular ore Our gold metallurgy expertise is second to none Chemical interference...

A significant contemporary challenge for gold mining companies is to define economic process options for treating more complex ore bodies as the less refractory ores become depleted Demonstration of economic treatment options allows gold companies to maintain and increase their ore reserv...

Refractory gold ores have increasingly been the main source of gold production with the exhaustion of amenable gold or Of the 2630 tons of total world gold production in 2011, about 25 was produced from refractory gold deposits, and of the top 20 gold operations in 2011, eight were processing refractory ores 1...

ABSTRACTCarlin-type refractory gold deposits are complex bodies which only occur in certain regions such as the western United States, southwest China, and northwest Iran It is important to investigate the most suitable treatment option for each deposit from the point of the mineralogical composition The present study investigates the effect of atmospheric NaOH alkaline pretreatment on the ....

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 ,...

Refractory gold ore pretreatment Treatment of refractory gold ore whole ore and flotation concentrates has become more prominent since the 1980s, with many gold discoveries often including ores that are wholly or partially refractory Refractory pre-treatment processes include pressure oxidation, biological oxidation and various forms of ....

This study was undertaken to evaluate the nitric acid leaching as a potential pre-treatment process prior to cyanidation of refractory gold/silver or The nitric acid pre-treatment experiments ....

Extraction of Gold from a Low-Grade Double Refractory Gold Ore Using Flotation-Preoxidation-Leaching Process , and P Sun, A mechanism study on technology of pretreatment of refractory gold ores , Xu B, Li Q, Jiang T, Lv P 2015 Extraction of Gold from a Low-Grade Double Refractory Gold Ore Using Flotation-Preoxidation-Leaching ....