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Sulphidic gold ore pretreatment in az

  • FLOTATION AND LEACHING AT ANGLO ASIAN MININGS

    Sep 08, 2017· Azerbaijan. The ore body is a complex copper-gold porphyry deposit, comprising intermixed oxidized, transition and sulphidic gold and copper-bearing ores. Gold in the sulphide ores is generally not refractory and is recoverable by cyanide leaching, but the secondary copper minerals, which are also cyanide soluble, lead to high cyanide consumptions.

  • Developments in the pretreatment of refractory gold

    This paper summarizes the technologies for the pretreatment of refractory gold ores using nitric acid as the oxidant. Pressure oxidation, atmospheric oxidation and the catalytically oxidizing technology of NOx processes can virtually always render refractory auriferous sulphidic

  • gold ore flotation treating - erapostmasburg.

    Mineralogy and Pretreatment of a Refractory Gold Deposit in Zambia. Jul 1, 2019 . gold deposit; mineralogy; gravityflotation combined; pretreatment . With the rapid depletion of easy to treat gold deposits and in order to ensure . In sulphidic refractory gold ores, gold

  • Sulphidic refractory gold ore pre-treatment by selective

    In sulphidic refractory gold ores, fine gold particles may be highly disseminated and locked up in sulphide minerals such as pyrite and arsenopyrite. Hence, pre-treating processes are necessary to extract gold for further processing methods like cyanidation. In this paper, the selective and bulk flotation methods are considered as primary

  • WO1998006878A1 - Precious metal recovery from refractory

    A process for obtaining access to refractory gold and/or silver carried by arsenopyrites and/or arsenical pyrites comprises first heating dry ore concentrate containing arsenopyrites and/or arsenical pyrites at a temperature from 450 °C to 850 °C in an oxidizing atmosphere of sulfur devoid of free oxygen to volatile the larger part of arsenic from the starting ore and then roasting the non

  • EP0113649A1 - A method for working-up complex sulphidic

    The invention relates to a method for selectively recover- ng the metal values of polymetallic sulphidic ore concen- :ates that contain lead and/or gold and other precious netals. The concentrate is treated in the following combina- :ion of process stages: a) roasting (2) under magnetite yielding conditions b) sulphating (4) in an oxidising environment to convert non-ferrous metals to sulphate

  • Agglomeration-Heap Leaching Operations in the - Arizona

    Gold recoveries obtained by agglomera- tion and heap leaching average 90 pct. Agglomeration pretreatment improved heap permeability, percolation rate, gold re- covery, and decreased the leaching period required to obtain the targeted recovery.

  • Developments in the pretreatment of refractory gold

    This paper summarizes the technologies for the pretreatment of refractory gold ores using nitric acid as the oxidant. Pressure oxidation, atmospheric oxidation and the catalytically oxidizing technology of NOx processes can virtually always render refractory auriferous sulphidic ores and concentrates amenable to cyanidation.

  • Chris Ralph's Gold Prospecting Encyclopedia: Information

    Chris' Prospecting Encyclopedia, Your best source of information on: Gold nuggets, gold panning, how to design and build your own mining equipment, metal detecting for nuggets, dredging for gold, prospecting books, California prospecting, 49ers, rock hounds, investing, mining stocks, mother lode, sulfides, turquoise, jewelry, silver, gold, gems, gold flakes, prospecting adventures, digging

  • Study on dearsenification of gold concentrate by microwave

    Yang fengyun. Refractory gold ore pretreatment process [J]. Science and technology communication,2013,45(6):107-108. [5] AmanKWah R K.M icrowave roasting of a carbonaceous sulphidic gold concentrate [J]. Minerals Engineering, 2009, 21 (22) : 1095-1101. [6] Cui G, Yang H Y. Bacterial oxidation of gold deposits with different arsenic types [J].

  • Extraction of Gold Then, Now and the Future

    Refractory Ores: Oxidative Pretreatment Applied when direct treatment by cyanidation gives unacceptable low gold recovery or is uneconomic due to: Gold is locked in relative gangue minerals often sulfides and cannot be adequately liberated even by fine grinding Gold occurs with minerals that consume unacceptable

  • One Novel two-step Bio-Oxidation Pretreatment of Arsenic

    oxidation process of refractory sulphide gold ores. Zhang [19] studied the enhanced effect of pyrolusite in the bio-oxidation process of refractory arsenopyritic gold ore. Currently, with the increasing industrial demand for gold-bearing ores, the utilization of high arsenic

  • minerals - minerals Article Mineralogy and Pretreatment of

    View minerals from CISO 3051 at University of Puerto Rico, Arecibo. minerals Article Mineralogy and Pretreatment of a Refractory Gold Deposit in Zambia Xu Wang 1 , Wenqing Qin 1, *, Fen Jiao 1, *,

  • CN100485059C - Method for recovering gold from sulphide

    The invention relates to a method for recovering gold from a sulphidic concentrate, particularly one containing arsenopyrite and/or pyrite, hydro- metallurgically. The concentrate is first subjected to leaching with a concentrated solution of alkali chloride and copper (II) chloride, by means of which the copper minerals and some of the gold in the concentrate are made to dissolve.

  • Gold Extraction from a High Carbon Low-Grade Refractory

    A high carbon low-grade gold ore, in which gold mainly occurs in carbonaceous matters, is a typical refractory gold ore whose conventional cyanide leaching extraction is only 12.9 %. In this paper, by the process of flotation-roasting-leaching, gold was effectively enriched and extracted.

  • US7785395B2 - Method for the recovery of gold from

    The invention relates to a method for recovering gold from a sulphidic concentrate, particularly one containing arsenopyrite and/or pyrite, hydro-metallurgically. The concentrate is first subjected to leaching with a concentrated solution of alkali chloride and copper (II) chloride, by means of which the copper minerals and some of the gold in the concentrate are made to dissolve.

  • (PDF) Treatment of a Copper-Rich Gold Ore by Ammonia

    Owing to the fact that cyanide forms strong complexes with gold, it is the most competent lixiviant for leaching of gold from ores (Senanayake, 2004;Breuer et al., 2005;Dai et al., 2010;Yang et al

  • Deposit in Zambia - MDPI

    The gold mineral should be pretreated before smelting due to the low grade of gold in the ore. The pretreatment process of gold mainly includes gravity separation, flotation, microbial oxidation, etc. [4,5]. Gold occurs usually in its native form or hosts in sulphides (especially pyrite, arsenopyrite,

  • Prevention of copper dissolution during cyanidation of

    The ores used in the tests were sulphidic gold containing ores from the Hope Brook mine in Canada. The copper content of the samples ranged from 0.42 wt % (HB/M) to 0.05 wt % (HB78). The sample used in Table 2 was HB/M of copper content 0.42 wt % as chalcopyrite. Table 3 shows assays of the major elements in the ore samples.

  • Pretreatment of a refractory arsenopyritic gold ore using

    Mar 01, 2015· For gold encapsulated in arsenopyrite or pyrite, pretreatments are necessary in order to break or alter the matrix of the sulfide (Chryssoulis and McMullen, 2005, Climo et al., 2000, Hashemzadehfini et al., 2011). The most common techniques include pre-aeration, roasting, high pressure oxidation and biological oxidation.

  • Agglomeration-Heap Leaching Operations in the - Arizona

    Gold recoveries obtained by agglomera- tion and heap leaching average 90 pct. Agglomeration pretreatment improved heap permeability, percolation rate, gold re- covery, and decreased the leaching period required to obtain the targeted recovery.

  • GOLD RECOVERY OF REFRACTORY SULFIDE CONCENTRATES

    The problem of refractory sulfide gold ore that has a gold recovery less than 50% when direct cyanidation applied, still exists until now. It needs oxidative pretreatment for cyanidation to be effective in gold recovery the objective of this study is figuring out the effect of sodium nitrite as an oxidizing reagent on cyanidation of refractory gold ore.

  • (PDF) Bacterial leaching as a pre-treatment step for gold

    Ores need not remain on prepared pads for long time periods (60-90 days is a common leaching time) to achieve acceptable levels of sulphide oxidation and subsequent gold recovery. Sulphidic material with as little as 0.7 g/t of gold content can be profitably bio-heap leached with 60-70% gold recovery.

  • Studies On Bio-Oxidation A Refractory Gold Containing

    Although bacterial leaching of sulphidic minerals is a well-known phenomenon, it is only in the last ten years that full-scale bacterial leaching plants have been commissioned for gold processing. In order for bacterial leaching to compete successfully with other pretreatment processes for refractory ores, particularly with established

  • Improvements in gold ore cyanidation by pre-oxidation with

    These types of gold sulphidic ores may be pre-treated prior to cyanidation by means of an oxidation step, converting the sulphides into oxides or sulphates. This treatment leads to a reduction in

  • Fungal pretreatment of sulfides in refractory gold ores

    In sulphidic refractory gold ores, tiny gold particles may be highly disseminated and locked up or occluded within the grain boundaries or fractures of sulphides, typically pyrite and arsenopyrite.

  • PRESSURE LEACHING OF SHALE ORE IN OXYGENATED

    of zinc, nickel, and copper sulphides and in pretreatment of refractory gold ores, in which gold is finely dispersed in sulphidic lattice. Especially, the pressure hydrometallurgy is widely used in nickel recovering from laterite ores. Currently, the tests are undertaken to apply hydrometallurgy for process of

  • (PDF) Bacterial leaching as a pre-treatment step for gold

    If the gold in a sulphidic ore or concentrate is predominantly disseminated in arsenopyrite, the more reactive arsenopyrite is preferentially oxidized than the pyrite. Consequently, liberated gold becomes available for recovery without the need to oxidize all of the sulphur.

  • (PDF) The Use of Oxygen in Gold Cyanidation Wesley

    This task is carried out with a series of tests planned through experimental design methodology.Three gold ores were evaluated in these studies. Gold ore sample A was crushed and ground to 80% passing -325 mesh (-45 pm). This fine size distribution is used at the mill to increase gold liberation. A second gold ore, sample B, was crushed and

  • Recovery of gold from sulfide refractory gold ore

    Apr 01, 2021· Especially for sulfide refractory gold ores, in order to recover gold, many oxidation pretreatment technologies were proposed including pyrometallurgical and hydrometallurgical processes, and a comprehensive summary of the respective pretreatment technologies is summarized in Table 1.

  • WO2014155753A1 - Method for pretreatment of gold ore

    Provided is a method for pretreatment of gold ore in order to leach out gold from gold ore containing pyrite, with which it is possible to suppress the generation of sulfide dioxide and to improve the leaching rate of gold. A method for pretreatment in order to recover gold contained in gold ore containing pyrite (FeS 2 ) by wet treatment, the method containing a step in which pyrite in gold

  • 280 RECENT ADVANCES IN THE TREATMENT OF REFRACTORY

    oxidation as a pretreatment method for refractory gold ores has been published by Berezowsky and Weir (6). According to them, the first patent on the use of pressure leaching for preoxidation of arsenical gold ores was granted to the Chemical Construction Company (Chemico) in 1955 (7). Two

  • ISSN (Print): 2328-3491, ISSN (Online): 2328-3580, ISSN

    main types of gold ores, namely refractory sulphidic gold ores, free milling and alluvial material. Refractory sulphidic concentrates, however, require pretreatment due to the mineralogy. Depending on the source of the material concentrated and the type of comminution process conducted, the concentrate may contain abraded

  • Pretreatment of Refractory Gold Ores Using Cell-Free

    The fungus Phanerochaete chrysosporium has been proven to biotransform refractory gold ores, leading to increase in gold recovery. This transformation has been attributed to enzymes secreted by the microbe. This paper reports the findings of preliminary investigations aimed at assessing the use of hydrogen peroxide and cell-free extracts from the fungus, P. chrysosporium, to effect

  • Pretreatment Process on Refractory Gold Ores with As

    The process of crushing or decomposition before gold leaching is called pretreatment of refractory gold. Statistics show that, in the world, about 2/3 gold resource belongs to the difficult processing ores, and about 1/3 total output of world gold is produced from refractory gold. This proportion will further increase in future.

  • pretreatment of refractory ores in gold leaching process congo

    Review Pretreatment Process on Refractory Gold Ores with As mineralogy of ores being encountered in which gold is locked up in various sulphidic host minerals. Gold ores are classified as highly refractory when at least 80% of the gold cannot be extracted by conventional cyanidation leaching even

  • Sulphidic refractory gold ore pre-treatment by selective

    Mar 01, 2013· In sulphidic refractory gold ores, fine gold particles may be highly disseminated and locked up in sulphide minerals such as pyrite and arsenopyrite. Hence, pre-treating processes are necessary to extract gold for further processing methods like cyanidation.

  • Sulphidic refractory gold ore pre-treatment by selective

    A high auriferous arsenopyrite floatability is desirable to maximise gold recovery in sulphidic refractory gold ore flotation. This study examines the adsorption properties of sulphidic refractory

  • Fungal-Transformation of Surrogate Sulphides and

    In the recovery of gold from refractory gold ores, pretreatment is required to decompose sulphides and liberate occluded sulphide sulphur in the residual sulphidic materials was also determined. From an initial preg-robbing effect of 125 µg of gold per gram of CM, the ability of CM to preg-rob gold reduced by 70-95% in the order of lignite

  • BACTERIAL LEACHING AS A PRE-TREATMENT STEP FOR

    expose the gold, the ore heap is washed with water to remove acid and metals. Lime is subsequently added to increase the pH and the ore is then treated with cyanide solution. Since the ore to be bio-oxidized in heap-leach configuration is quite coarse, usually > 6.5 mm, the percent gold recovery is remarkably lower then would be

  • Anglo Asian Mining plc 20/521 Yard Huseyn Javid Avenue

    Azerbaijan. The ore body is a complex copper-gold porphyry deposit, comprising intermixed oxidized, transition and sulphidic gold and copper-bearing ores. Gold in the sulphide ores is generally not refractory and is recoverable by cyanide leaching, but the secondary copper minerals, which are also cyanide soluble, lead to high cyanide consumptions.

  • Gold extraction - Wikipedia

    Gold extraction refers to the processes required to extract gold from its ores.This may require a combination of comminution, mineral processing, hydrometallurgical, and pyrometallurgical processes to be performed on the ore.. Gold mining from alluvium ores was once achieved by techniques associated with placer mining such as simple gold panning and sluicing, resulting in direct recovery of

  • Microwave pretreatment of a double refractory gold ore

    Abstract Double refractory gold ores, such as Barricks 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

  • pretreatment of refractory ores in gold leaching process congo

    Pretreatment of a refractory arsenopyritic gold ore using . 01-03-2015· 1. Introduction. The recovery of precious metals from refractory ores has been widely investigated due to depletion of the deposits from which gold can be easily leached (Abrantes and Costa, 1996, Ofori-Sarpong et al., 2011).There are numerous causes and degrees for refractory behavior: the presence of carbonaceous matter

  • (PDF) Bacterial Leaching as a Pre-treatment Step for Gold

    In this article, pre-treatment such as bio-leaching before cyanidation is discussed as an alternative technique to treat refractory gold ores containing pyrite and arsenopyrite. There are two

  • Mineralogy and Pretreatment of a Refractory Gold Deposit

    The pretreatment process of gold mainly includes gravity separation, flotation, microbial oxidation, etc. [ 4, 5 ]. Gold occurs usually in its native form or hosts in sulphides (especially pyrite, arsenopyrite, and chalcopyrite), silicate, carbonate, and oxide minerals [ 1, 6, 7 ].