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The cyanide species in the gold tailings are classified as free cyanide, weak acid dissociation, and metallocyanide complexes. Several methods, such as …
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The Yukon government says it has "lost confidence" in the Victoria Gold Corporation's management team to effectively remediate the on-site cyanide …
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Mining dumps and tailings are frequently the principal source of solid waste as well as liquid waste pollution, affecting public health and social community …
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Deportment studies of gold in tailings show that gold losses can occur either as liberated gold particles or as fine gold locked in sulfide and non-sulfide minerals, with locked-gold predominating. Studies ... cyanide. Gold in Figure 1d occurs as submicroscopic gold in disseminated pyrite, making the gold extremely refractory. ...
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1. Introduction. About 90% of the world's gold mining workforce is represented by artisanal and small-scale gold miners, producing around 15% of the world's gold (UNEP, 2012).In Colombia there are about 200,000 artisanal gold miners, using mainly mercury for the gold processing (Cordy et al., 2011).The amalgamation process …
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Due to this type of operations, it is possible to find mining tailings dams which contain 0–25 ppm of cyanide species (Dash et al., 2009), as can be seen this concentration range is lower than that found in some cigarettes (0.5 mg/cigarette), however, from an environmental viewpoint, the accumulation of cyanide species in the mining …
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The aim of this study was to investigate the availability and fate of cyanide in gold mill solid tailings. For this purpose, aged (6–9 years) and recently discharged (3 months) tailings were sampled at various depths from two gold mining sites in …
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Rafiei et al., reported a pH value of 7.35 in gold mine tailings in Iran, whereas Mitileni et al., reported pH values of 3.25–6.28 in South Africa and Harish and David pH value of 3.48–8.12 in India. Highly acidic pH has also been observed in acid mine drainage arising from gold mining activity in other studies [25,26].
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study, the cyanide degradation of a B. subtilis strain iso-lated from artisanal gold mining tailings was thus analyzed under alkaline conditions in order to assess the potential of biotreating cyanide-containing effluents using native bacteria. Material and methods In order to assess the potential for cyanide biodegradation
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One of the world's largest copper-gold mines, Oyu Tolgoi, was settling in, and herder communities were being forced to resettle without consultation.
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Ahtiainen R, Lundström M. Cyanide-free gold leaching in exceptionally mild chloride solutions. Journal of Cleaner Production. 2019; 234:9-17. DOI: 10.1016/j.jclepro.2019.06.197; 38. Li H, Ma A, Srinivasakannan C, Zhang L, Li S, Yin S. Investigation on the recovery of gold and silver from cyanide tailings using chlorination …
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The planetGOLD Programme, together with the UNEP Global Mercury Partnership and its area of work on Mercury in Artisanal and Small Scale Gold Mining, jointly organized an online information-sharing session dedicated to best management practices in the use of cyanide on Tuesday 25 January 2022.. As the use of cyanide becomes more prevalent …
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Previous gold mining activities resulted in the discharge of tailing materials containing various hazardous trace metals such as manganese (Mn), nickel (Ni), arsenic (As), cadmium (Cd), cobalt (Co ...
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Chile's miners are also adopting alternatives such as paste, co-disposal, filtered, or thickened tailings. Dry stack tailings permit the recovery of the maximum …
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It is known that the tailings of gold mines have brought serious heavy metal pollution; however, the heavy metal pollution caused by gold tailings in specific geological environments and extraction processes still must be studied. ... bioaccumulation … Heavy metal pollution caused by cyanide gold leaching: a case study of gold tailings in ...
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Request PDF | A kinetic-mechanistic study of cyanide degradation which can be contained in mining tailings dams using a divided electrolytic cell | Cyanidation is considered the most employed ...
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This study assessed the effectiveness of the current cyanide management practice of a large gold mine as a case study of Thailand's cyanide-contaminated mine waste management policy. ... dangers from the mine's HCN emissions, cyanide levels in tailings must be carefully calculated and regulated using the HCN dispersion model, …
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Mexico is the top producer of silver and is on the eighth place from producing gold in the world. For instance, the hydrometallurgical extraction process produces wastewater (mining tailing) characterized by being composed with varying concentrations of cyanide and heavy metals. The purpose of this research was to study the …
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Most of the cyanide remains in the solution or the slurries after the cyanidation process. The cyanide species in the gold tailings are classified as free cyanide, weak acid dissociation, and metallocyanide complexes. Several methods, such as colorimetric, titrimetric, and electrochemical, have been developed to determine cyanide …
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Cyanide tailings are industrial hazardous solid wastes arising from gold mining industry. Hundreds of millions of tons of cyanide tailings that contain highly toxic cyanides and various valuable elements, such as gold, silver, iron, sulfur, copper, lead, and zinc are generated and discharged to tailing dams every year. ... In this study, the ...
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Although the total cyanide (T-CN) concentration (1.4–1.9 mg kg −1) found in most of the study area falls within the limits of gold mining tailing values for American sites (1.5–23 mg kg −1), it is worth noting that the values of the tailings of the last used mining operation exceed it (25.2–518 mg kg −1) and persist at the site. The ...
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The gold-mining industry commonly uses the cyanide process to recover gold from complex ore. During the gold cyanidation process, cyanide bearing water will react with sulfide in the ore to form ...
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The detection standard is that the total cyanide content in the tailings toxic leaching solution is less than 0.05 mg/L, while the national standard GB/T 14848-2017 "Quality of Groundwater" The ...
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Cyanide and potentially toxic elements in tailings from gold mining can cause serious pollution, and harm the surrounding environment through rainfall seepage and leakage from tailings ponds.
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It can be seen from Table 1 that cyanide tailings contain gold, silver, copper, lead and zinc of recovery value. Gold was wrapped by quartz and silicate (41.93%), and included by pyrite and copper, lead and zinc sulfide (40.88%) (Table 2).In addition, the content of SiO 2 was high, and contained some Al 2 O 3, CaO, MgO, Na 2 O, K 2 O, …
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gold. The use of cyanide mostly occurs at gold pro-cessing centres and larger AGSM operators within gold mining communities (Velasquez-Lopez et al., 2011; Veiga et al., 2014). Central Processing Centres in AGSM communities are facilities where miners send their gold-bearing ores or tailings to be extracted by dedicated operators for a fee.
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Endeavour's Sustainalytics score has improved from the 72nd percentile in 2019 to the 9th percentile (1st = lowest risk) for 2022, ranking the company fourth …
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1. Introduction. In recent decades, gold mining expanded from its historical core (South Africa, the United States, Canada, Australia, and Russia) into a wide range of new gold mining regions, many of them located in the global South (Verbrugge and Geenen, 2020).In addition to the expansion of large-scale industrial mining, many of …
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A highly toxic chemical that can be dangerous to humans and wildlife, cyanide use at gold mining operations provokes concern in many jurisdictions. In fact, it was in response to a damaging spill from a tailings pond in Romania in 2000 that released 100,000 cubic metres of cyanide contaminated water into the Somes River, that the …
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Free cyanide is not persistent in the tailings environment (Botz et al., 1995, Resource Assessment Commission, 1991) and will degrade through physical, chemical and biological processes, into other less toxic chemicals (Environment Australia, 2003).Natural degradation, primarily by volatilisation of cyanide in TSFs, is the most common method …
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