effect of excess cyanide in leaching of uranium pdf





Hot Searchs

New Technology for Recovery of Gold and Silver by ,New Technology for Recovery of Gold and Silver by Pressure Cyanidation Leaching and Electrocoagulation , Because of this, before the cyanidation process excessive lime or caustic soda must be used in or der to the pH of the pulp to 10 or 11 , minerals and leaching the Au/Ag with the cyanide ions, simultaneously in a single stage...know more

The major role played by calcium in T gold plant circuitsserious effect on the kinetic response, loadings of 40 to 60 kg/t have a detrimental effect on gold adsorption The deleterious effect on leaching caused by excessive additions of calcium in the leach circuit6 may also be explained by the adsorption of this calcium aurocyanide complex by ,...know more

US4337979A - Process for the in-situ leaching of uranium ,Process for the in-situ leaching of uranium from a subterranean ore deposit employing a lixiviant containing an oxidizing agent, sulfuric acid, and carbon dioxide Prior to the injection of the lixiviant, an aqueous solution of sulfuric acid and oxidizing agent is injected into the deposit in an amount of at least 1 pore volume The initially injected acid solution is substantially free of ....know more

Improvement of Stability of Hydrogen Peroxide using ,(though excess use may increase consumption of cyanide) [1, 3], precipitation of uranium or plutanoium in peroxide form from pregnant leach solutions (PLS) [2,4] and sulphate/chloride leaching of copper from its ores/concentrates [5, 6] and waste materials such as waste electrical...know more

Re-Processing Gold Tailings in South Africathe leach residue The slurry discharge from the autoclave will then be combined with the cleaner scavenger tailings in a hot atmospheric leaching (AL) circuit, in which the acid and ferric ions generated during POX will be utilized to leach uranium and oxidize some of the pyrite in the cleaner tailings...know more

Interference of Metals with the Determination of Free CyanideIn cyanide leaching plants, free cyanide level in leach solutions is commonly controlled by silver nitrate titration The presence of zinc in solutions leads to an overestimation of free cyanide ....know more

Calcium Sulfide Precipitation of Mercury During Cyanide ,CALCIUM SULFIDE PRECIPITATION OF MERCURY DURING CYANIDE LEACH ING OF GOLD ORES By R G Sandberg, 1 W W Dimpson, 2 and W L Staker 2 ABSTRACT Many gold-bearing ores throughout the Western United States contain small quantities of mercury The presence of mercury not only decreases...know more

Leaching and recovery of platinum group metals from UG ,Leaching and recovery of platinum group metals from UG-2 concentrates yields were not good (less than 40 per cent) Platinum leaching was particularly poor with cyanide (ambient temperature) A HCl/chlorine leach on untreated material had the same effect as a cyanide leach with a nitric acid pre-leach....know more

Effects of stripping parameters on cyanide recovery in ,It is also known that gold and silver leaching of tailings with a higher cyanide concentration requires a larger G/L ratio or a taller stripping column (Botz et al, 1995) Fig 5 shows the effects of variations in G/L ratio on cyanide recovery as a function of stripping time The total height of the stripping column (6 m) was required to reach ....know more

Optimizing and evaluating the operational factors ,Optimizing and evaluating the operational factors affecting the cyanide leaching circuit of the , have concluded that using an excess of cyanide results in unnecessary cyanide consumption and has no beneficial effect on gold extraction The excess cyanide will consume more cyanide because of the formation of cyanocomplexes from impurities ....know more

Copper: Health Information Summary - New HampshireCopper: Health Information Summary Copper is a naturally-occurring metallic element that occurs in soil at an average concentration of about 50 parts per million (ppm) It is present in all animals and plants and is an essential nutrient for humans and animals in small amounts...know more

CCR Appendix D Source and Health Effectsthese byproducts in excess of the MCL may lead to adverse health effects, liver or kidney problems, or nervous system effects, and may lead to an increased risk of getting cancer Turbidity (NTU) TT TT N/A Soil runoff Turbidity has no health effects However, turbidity can interfere with disinfection and provide a medium for microbial growth...know more

Cyanide Leaching Chemistry & Gold CyanidationThe reactions that take place during the dissolution of gold in cyanide solutions under normal conditions have been fairly definitely established Most agree that the overall cyanide equation for leaching and cyanidation of gold is as follows: 4 Au + 8 NaCN + ,...know more

5 Health Effects of Excess Copper | Copper in Drinking ,THIS chapter focuses on the health effects associated with acute and chronic exposure to excess copper Information on those effects comes from human case-reports and population-based studi The emphasis is placed on acute exposure effects on the gastrointestinal (GI) system Effects on other ....know more

Aurorra Gold Mining: Non Cyanide LeachingThe CLS leaching solution was Action Mining's first product, but just as important is the technology attached to this leach solution Since CLS is different than cyanide or any other leach solution now in use, this new technology must, in some manner, be ,...know more

CYANIDE RECOVERY COST EFFECTIVENESS IS WHY RECYCLE ,cyanide in the tailings can therefore have a major influence on the economic health of a project The economic impact of cyanide is different in every operation, but it is possible to compare cyanide destruction and cyanide recovery costs for a fairly generic high cyanide-consuming case The capital cost of a cyanide recovery...know more

Copper and Cyanide Recovery in Cyanidation Effluentslute cyanide solution, typical of leach conditions found in the gold cyanidation process Minerals such as azurite and malaquite, are fast leached and soluble in dilute cya-nide solutions Enargite and chalcopyrite leach more slowly but are sufficient soluble to cause excessive cya-nide loss and contamination of leach solutions with arse-nic [5]...know more

CYANIDE REMEDIATION: CURRENT AND PAST TECHNOLOGIES104 Proceedings of the 10th Annual Conference on Hazardous Waste Research CYANIDE REMEDIATION: CURRENT AND PAST TECHNOLOGIES CA Young§ and TS Jordan, Department of Metallurgical Engineering, Montana Tech, Butte, MT 59701 ABSTRACT Cyanide (CN-) is a toxic species that is found predominantly in industrial effluents generated by metallurgical operations Cyanide's ,...know more

Improvement of Stability of Hydrogen Peroxide using ,(though excess use may increase consumption of cyanide) [1, 3], precipitation of uranium or plutanoium in peroxide form from pregnant leach solutions (PLS) [2,4] and sulphate/chloride leaching of copper from its ores/concentrates [5, 6] and waste materials such as waste electrical...know more

Mineralogy and uranium leaching response of low grade ,In the recovering of uranium as a by-product of gold production, two process routes can be considered with respect to gold recovery: (i) forward leaching (direct cyanide leaching of gold) and (ii) reverse leaching (sulphuric acid leaching of uranium followed by cyanide leaching ,...know more

Treatment of copper-rich gold ore by cyanide leaching ,The treatment of a copper sulphide-bearing gold ore by direct cyanide leaching, ammonia pretreatment and ammoniacal cyanide leaching was investigated Dissolution behaviour of gold and copper in these leaching systems was demonstrated...know more

MODELING OF GOLD CYANIDATIONModeling of gold cyanidation Master of Science (Technology) Thesis 2008 , The effect of leaching parameters on gold cyanidation is studied in this , Figure 8 Effect of cyanide concentration on leaching Pre-leaching: pH 112, 8 ppm O 2, 100 g/t Pb(NO 3)...know more

METHOD 9016 FREE CYANIDE IN WATER, SOILS AND SOLID ,FREE CYANIDE IN WATER, SOILS AND SOLID WASTES BY MICRODIFFUSION , Figure 3 illustrates the effects of various extraction conditions on the recovery of free cyanide in a complex, mixed-waste sample , sulfide) can be removed by adding an excess of either lead carbonate or lead...know more

Chapter - L HYDROMETALLURGY & SOLUTION MININGABSTRACT The effect of temperature on the rate of gold dissolution from copper anode slime by chloride leaching was investigated A series of experiments were conducted in a temperature range of 30 to Û& WR evaluate the kinetics and thermodynamics of gold dissolution...know more

Alternative Lixiviants to Cyanide for Leaching Gold Ores ,Higher reagent concentrations compared to those used in cyanide leaching make recycling important to make gold extraction by alternative lixiviants economical The complexity of the process may be substantially greater than in cyanide leaching, potentially requiring nonstandard monitoring equipment and specialized training of staff...know more

Gold-Precious Metals ConferenceFigure 3: Effect of free cyanide concentration on Cu(I) speciation at 10 mg/L Cu and pH 10 (4) Gold Recovery Via Activated Carbon from Cyanide Liquors Containing Cuprous Cyanocomplexes Activated carbon is widely used for gold recovery from cyanide leach liquors via in-leach carbon-(CIL) or carbonin-pulp (CIP) technology...know more

New Technology for Recovery of Gold and Silver by ,New Technology for Recovery of Gold and Silver by Pressure Cyanidation Leaching and Electrocoagulation , Because of this, before the cyanidation process excessive lime or caustic soda must be used in or der to the pH of the pulp to 10 or 11 , minerals and leaching the Au/Ag with the cyanide ions, simultaneously in a single stage...know more

Interference of Metals with the Determination of Free CyanideIn cyanide leaching plants, free cyanide level in leach solutions is commonly controlled by silver nitrate titration The presence of zinc in solutions leads to an overestimation of free cyanide ....know more

A review of acid leaching of uraninite | Request PDFA review of acid leaching of uraninite , Laboratory-scale leach tests for gold (cyanide) and uranium (sulphuric acid) were carried out using dissolution conditions similar to that in use at the ....know more

Cyanide Leaching Of Gold - Mine EngineerComCyanide Leaching Of Gold , Arsenic and antimony do present a larger problem, by reacting with the cyanide and using up all of the excess oxygen, leaving little or no oxygen to effect the dissolution of gold Carbonaceous gold ores can have the carbon adsorb the gold onto its surface, and as a result will not be recovered from the pregnant ....know more