Recovery of gold from sulfide refractory gold ore: Oxidation …
— Most of the gold in the roasting slag is recovered by thiourea/cyanide leaching process, however, the leaching residues (gold tailings) obtained from thiourea leaching process or the sodium cyanide leaching still contain 9–16 g/t gold, which is difficult to recover and is usually discarded with the leaching residues; This phenomenon is …
Heavy metal pollution caused by cyanide gold leaching: a case study …
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 ...
Determination and detoxification of cyanide in gold mine …
— The cyanide species in the gold tailings are classified as free cyanide, weak acid dissociation, and metallocyanide complexes. Several methods, such as …
Reaction of Cyanide with Hg 0-Contaminated Gold Mining Tailings
— Elemental mercury (Hg 0) contamination in artisanal and small-scale gold mining (ASGM) communities is widespread, and Hg 0-contaminated tailings are often reprocessed with cyanide (-CN) to extract residual gold remaining after amalgamation. Hg 0 reacts with -CN under aerobic conditions to produce Hg(CN) 4 2-and other Hg(CN) n n-2 …
Reaction of Cyanide with Hg0-Contaminated Gold Mining Tailings …
— The findings from this study are the first to show that Hg(CN)2 complexes are highly stable complexes that can lead to cellular injury and death in mammalian organ systems. Elemental mercury (Hg0) contamination in artisanal and small-scale gold mining (ASGM) communities is widespread, and Hg0-contaminated tailings are often …
(PDF) Impacts of cyanide in gold mining and cyanide …
— ABSTRACT The aim of this work was to present an overview of studies on the use of mining tailings in the State of Pará from 2010 to 2020. ... decomposition of cyanide from gold leaching tailings ...
The cyanide revolution: Efficiency gains and exclusion in …
— 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 …
Spatial distribution and risk assessment of pollutants in a tailings …
— 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. In this study, 40 surface soil samples were collected from the Liujiadian tailings pond basin in Pinggu District, Beijing, and the contents of cyanide, Sb, …
Environmental Impact Assessment of Mine Tailings Spill …
— The generation of tailings in the world today is immense, since only ounces or pounds of metals are extracted for each ton of ore processed. In 2022, it was estimated that more than 14 billion metric tons of mining tailings were produced per year in the world. Currently, many environmental problems associated with tailings management in both …
Cyanide and cyanidation wastes management in gold …
— The socio-economic benefits of gold extraction through cyanidation of mercury-contaminated tailings notwithstanding, the study establishes inadequate …
Current situation and prospects for the clean utilization of gold tailings
— Cyanide tailings used in the study by Zhang et al. (2012) are residues obtained after extracting gold from gold tailings by conventional cyanidation or roasting-cyanidation processes. ... Gold mining tailing: environmental availability of metals and human health risk assessment. J Hazard Matert, 397 (2020) ...
Spatial distribution and risk assessment of pollutants in a …
In the early days, waste from gold mining in Pinggu District accumulated on the ground and was exposed to the environ - ment. From 2004 to 2006, the Pinggu District Government established tailings ponds to contain all gold tailings in the area. These tailings ponds have been closed for 17 years, mining activities have long been banned and acid mine
Experimental analysis on cyanide removal of gold tailings
— The cyanide content of gold tailings exceeds the standard seriously due to the cyanide extraction process. In order to improve the resource utilization efficiency of gold tailings, a medium ...
Characterization and availability of cyanide in solid mine tailings …
— 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 …
First insight into the natural biodegradation of cyanide in a gold …
— The disposal of mining wastes that contain cyanide are dumped in tailings from gold extraction is a public concern in mining countries such as South Africa. Many studies have shown the potential of microorganisms to degrade cyanide. However, no in-situ exploration, in tailings contaminated with cyan …
Biodegradation of cyanide using a Bacillus subtilis strain …
— Artisanal and small-scale mining are informal activities used as a source of family income in many countries, mostly in developing regions. They also represent rudimentary practices that generate environmental and health impacts. In these activities, gold is the main mineral extracted commonly using cyanide leaching as the main …
(PDF) Physico-chemical Characteristics of a Gold Mining Tailings …
— The study was conducted on the status of the quality of wastewater from the tailings dam of Central Africa Gold Limited in Bibiani, Ghana, to ascertain the level of contamination of the wastewater.
Factors influencing the risk of wildlife cyanide poisoning on …
— Wildlife and livestock that ingest bioavailable cyanide compounds in gold mining tailings dams are known to experience cyanide toxicosis. Elevated levels of salinity in open impoundments have been shown to prevent wildlife cyanide toxicosis by reducing drinking and foraging. ... During this study, cyanide-bearing solutions stored in open ...
A critical review of the effects of gold cyanide-bearing …
Cyanide concentrations below 50 mg/L weak-acid-dissociable (WAD) are deemed safe to wildlife but are considered an interim benchmark for discharge into tailings storage …
Cyanide contamination of soil and water: Sources, toxicity, …
— Cyanide (CN −) is a silent killer and is highly toxic to the environment and biological life (Kaszeta, 2020).Also known as isocyanides, cyanide ions, cyanide anions, or cyanide (1−) ions, cyanides are composed of a carbon atom triple bonded to a nitrogen atom (C N) (Adeola, 2011).Given its acute toxicity, cyanide is harmful to health and the …
A critical review of the effects of gold cyanide-bearing tailings
The formation of copper-cyanide complex occurs preferentially to gold cyanide complex indicating the relative importance of economic vs. environmental considerations in the tailings water. Management of cyanide to a perceived threshold has inherent risks since cyanide has a steep toxicity response curve; is difficult to accurately measure in ...
Determination and detoxification of cyanide in gold mine …
— The thermal decomposition rule of cyanide in gold tailings was analyzed, and the effects of different roasting temperatures and roasting durations on cyanide removal …
Decomposition of Cyanide from Gold Leaching …
— Cyanidation is widely used by most gold mine worldwide and will remain prevail in years (or decades) to come, while cyanide is hazardous, toxic pollutants whose presence in wastewater and tailings …
A kinetic-mechanistic study of cyanide degradation which …
— 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 tailings ...
First insight into the natural biodegradation of cyanide in a …
— The disposal of mining wastes that contain cyanide are dumped in tailings from gold extraction is a public concern in mining countries such as South Africa. Many …
Microbial destruction of cyanide wastes in gold mining
Microbial destruction of cyanide and its related compounds is one of the most important biotechnologies to emerge in the last two decades for treating process and tailings solutions at precious metals mining operations. Hundreds of plant and microbial species (bacteria, fungi and algae) can detoxify cyanide quickly to environmentally acceptable levels and …
The detoxification and utilization of cyanide tailings: A …
— 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 ...
CYANIDE MANAGEMENT
2.0 CYANIDE IN MINING 3 2.1 Cyanide in context 3 2.2 Gold extraction 5 2.3 Alternatives to cyanide 7 2.4 Cyanide treatment, recovery and reuse 7 2.5 Control of process losses 8 3.0 CYANIDE AND THE ENVIRONMENT 9 3.1 Cyanide ecotoxicology 9 CASE STUDY: Sunrise Dam gold mine, tailings and compliance with the ICMC 11 3.2 Environmental …
Process effluents and mine tailings: sources, effects and
— Cyanide de-toxification of mining wastewaters with TiO 2 nanoparticles and its recovery by electrocoagulation was studied by Parga et al. . They reported that photo-degradation of cyanide is 93% in 30 min using a 450-W halogen lamp and the recovery of anatase with the electro-coagulation process is 98%. ... Further, a study of gold grains …
A critical review of the effects of gold cyanide-bearing …
— Cyanide allows gold to be dissolved at a range of pH levels, although the stability of cyanide is greater at a higher pH. For gold mining metallurgical purposes, …
Determination and detoxification of cyanide in gold mine tailings…
— 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 ...
The detoxification and utilization of cyanide tailings: A …
— 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 ...
Gold recovery from synthetic mine tailings leachate using …
— 1. Introduction. 8.75 billion tonnes of waste globally are created from gold mining annually (Earthworks and Oxfam America 2004).Solid waste streams generated from gold mining and processing, better known as mine tailings, still contain a significant mass of gold, with a global estimate of around 425 tonnes (Ogola et al., 2017).The U.S. …
Mercury methylation in cyanide influenced river …
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.
Reprocessing of Gango Gold Mine Tailings via Different …
Keywords: tailings, gold, cyanide leaching, thiourea leaching, thiosulfate leaching, iodine leaching INTRODUCTION The Gango Gold Mine, located at barangay Gango municipality of Libona province of Bukidnon, Philippines, is a "Minahang Bayan" (People's Mining Area), as declared by the Department of Environment and Natural Resources Mines ...