In February 2001, Kalgoorlie Consolidated Gold Mines (KCGM) commissioned its first full-scale ultra fine grinding (UFG) plant to supplement its existing roaster-concentrate treatment capacity. The process involves the fine grinding of refractory pyritic concentrate to 10 Jim followed by direct cyanide leaching for gold recovery.
Preliminary tests have confirmed that ultra-fine grinding substantially improves the extraction of silver from the tailings in cyanide leaching (i.e. 36% Ag extraction from the as-received ...
Extremely fine (<10μm) particles are locked within an impervious, unreactive mineral. This can be overcome by ultra-fine grinding. However, this is often not economically viable. If the gold is encapsulated in sulfides, oxidation of the sulfide minerals by roasting, pressure oxidation, or bio-oxidation is used. Chemical Interference
DOI: 10.1016/S1003-6326(13)62882-4 Corpus ID: 56106153; Ultra fine grinding of silver plant tailings of refractory ore using vertical stirred media mill @article{Celep2013UltraFG, title={Ultra fine grinding of silver plant tailings of refractory ore using vertical stirred media mill}, author={Oktay Celep and Ersin Yener Yazici}, journal={Transactions of Nonferrous …
Ultra fine grinding by using stirred media mills has recently received great interest for treatment of refractory gold ores or plant tailings (Corrans and Angove, 1991;Davey, 2010;Celep et al ...
Reducing the particle size from 27 to 7.5 µm (d 80) by ultra-fine grinding adversely affected the leaching performance in that the extraction of Au and Ag markedly decreased from 40.2% to 10.4% ...
Ultra fine grinding (UFG) can be suitably practiced to improve metal extractions from those ores that contain the locked gold with 1 2 to 20 µm in size (Celep et al., 2011a; Corrans and Angove ...
Ultrafine grinding of a pyrite ore to reduce the 80% passing size (P80) from 74 to 10 μm increased gold recovery from 23.4 to 70.2% by cyanidation . Mechanical activation of bio-oxidized gold ores improved gold recovery by up to 1.8 times by cyanidation [ 11 ].
Since early-2001, Kalgoorlie Consolidated Gold Mines (KCGM) has successfully operated an ultra fine grinding (UFG) circuit to supplement its roaster capacity for the treatment …
Ultra fine grinding by using stirred media mills has recently received great interest for treatment of refractory gold ores or plant tailings (Corrans and Angove, 1991;Davey, 2010; Celep et al ...
UFG of pyritic concentrates for subsequent leaching is used in ores where refractoriness to direct cyanidation arises from fine to ultrafine (0.02 -20 μm) gold mineral inclusions in the pyrite ...
Not all refractory gold ores give a large recovery improvement after fine milling. Gold locked in arsenopyrite for example does not achieve the same gold recovery as gold disseminated in pyrite due to the smaller gold particle size of the locked gold (Figure 5). Figure 5. Gold Recovery of Arsenopyrite and Pyrite Ores 50 55 60 65 70 75 80 85 90 ...
Effect of grinding time on particle size (3mm steel ball; 750rpm) 723 The effect of ultrafine grinding on gold and silver extractions from the ore is shown in Fig. 3 and 4, respectively. The most of gold and silver was gone into solution over the initial two hour of cyanidation.
Ultrafine grinding (UFG) was proposed as a pretreatment method prior to cyanide leaching of old plant tailings of a refractory silver ore. Direct cyanidation of the as-received tailings (d80: 100 µm) led to a low silver extraction of only ≤43% over 24 h. A size-based diagnostic study has demonstrated that the refractoriness of the tailings is essentially physical in …
In terms of the nature and size of gold grains, ores are often classified as containing microscopic gold, submicroscopic gold and surface gold. Gold in various ores is …
The original application for ultra-fine grained orebodies is a relatively small niche, but it is ... ore) as grinding media These features distinguish stirred mills as fundamentally different from both ball mills and Tower Mills, as demonstrated by Tables 1 and 2. ... (eg exposing fine gold to cyanide). In this case dissolution of the
Abstract. Since early 2001, Kalgoorlie Consolidated Gold Mines (KCGM) has successfully operated an ultra fine grinding (UFG) circuit to supplement its roaster capacity for the treatment of the refractory gold flotation concentrate. A second UFG mill was installed in …
Since early 2001, Kalgoorlie Consolidated Gold Mines (KCGM) has successfully operated an ultra fine grinding (UFG) circuit to supplement its roaster capacity for the treatment …
Ultra-fine grinding. If the locked gold measures between 2 and 20 μm, ultra-fine grinding can be employed, which involves intensive milling and particle disintegration (Celep et al., 2011; Corrans and Angove, 1991).
The PolarFit ultra-fine-grinding mill is available in a range of sizes to meet your needs Model 100 200 400 800 1200 1600 Scale-up factor 0.25 1.0 2.5 6 8.8 13
Table 1 .The Effect of Ultrafine Grinding on Gold Recovery from Pyritic Ore. Figure 4. Gold Recovery versus Particle Size for a Refractory Gold Ore Ultrafine grinding resulted in a significant improvement in the gold recovery through cyanidation. Typical gold recoveries for the ore sample, when ground to 80 % passing 75
The tailings from Shuiyindong Gold Mine have a large grinding fineness, in which the ultra-fine particles (with the particle diameter below 20 μm) occupy 66.13% and the fine particles (with the particle diameter below 75 μm) occupy as high as 92.22%.
Hence ultra-fine grinding which exposes the gold followed by cyanide leaching was selected with the arsenopyrite returning to the tailings in an unaltered state. The plant …
Ultra fine grinding of the plant tailings of a refractory silver ore was studied using a laboratory type vertical stirred media mill. Preliminary tests confirmed that ultra fine grinding substantially improves the extraction of silver from the tailings in cyanide leaching (i.e. 36% Ag extraction rate from the as-received tailings with d 80 of 100 μm, c.f. 84% …
The physical lock-up of gold can be overcome by ultra-fine grinding of the ore to liberate the locked gold or enable the complete destruction of the mineral when present in the solid solution within the mineral matrix in the form of molecular or "invisible" gold [16, 17]. However, the ultra-fine grinding is a physical method for the exposed ...
Ultra-Fine Grinding: In cases such as ore containing pyritic gold, the gold is often finely disseminated in the mineral matrix at sub 10 µm particle size and consequently can be …
Since early-2001, Kalgoorlie Consolidated Gold Mines (KCGM) has successfully operated an ultra fine grinding (UFG) circuit to supplement its roaster capacity for the treatment of the refractory gold flotation concentrate. A second UFG mill was installed in 2002 taking the total UFG capacity to over 20 tph while grinding to 11 to 12 microns and achieving over …
Young et al, 2000). These are required for ultra-fine grinding to achieve liberation of fine-grained minerals, which improves separation of th e minerals in the flotation circuits. The process parameters and IsaMill designs have been continuously improved to increase the IsaMill grinding performance and the component life between maintenance ...
1. Introduction1.1. Background. With the continual depletion of high grade simple ore bodies, more complex, finely disseminated ore bodies are being processed, which has led to an increase in the prevalence of fine grinding (Sinnott et al., 2006).This has been evident in the platinum group element (PGE) industry in South Africa, where …
This laboratory work presents a study of the effect of ultrafine grinding on the gold recovery of a highly refrac-tory gold concentrate. The particle size of the concentrate was P 80 = 46 μm and ...
Improvement of Silver Extraction by Ultra-fine Grinding prior to Cyanide Leaching of the Plant Tailings of a Refractory Silver Ore ... (Zhou et al. 2009). In fact, silver ores or silver in gold ores often respond poorly to the chemical pretreatment processes leading to low silver extractions compared with gold (Celep et al. 2009; Zhou 2010 ...