scholarly journals Increasing gold recovery from poor ore using gravity

2021 ◽  
Vol 13 (4) ◽  
Author(s):  
Moussa Koulibaly ◽  
Tatiana Chekushina ◽  
Alexey Yankevskiy
Keyword(s):  
Climatic Conditions ◽  
Gold Recovery ◽  
Test Method ◽  
African Continent ◽  
Gold Production ◽  
Republic Of Guinea ◽  
Ore Processing ◽  
Useful Components ◽  
Maximum Extraction ◽  
Gold Bearing

The article discusses the issues of increasing the efficiency of extraction of gold-bearing ores from poor ores using gravity using combined geotechnologies at the Sigiri mine (Republic of Guinea). Gravity Recoverable Gold (GRG) is defined as gold present in a particle in sufficient quantities to be selectively recovered from waste rock by gravity methods. Since Guinea is one of the ten leaders among the countries of the African continent in terms of gold reserves (2019 — 700,000 tons), it should be taken into account that the complex of measures for ore processing includes crushing modules interconnected during the technological process, grinding-gravity module, flotation module and metallurgical a module that affects the solution of the problem of integrated development of subsoil in the generally accepted understanding and this is the maximum extraction of recorded reserves from the subsoil and useful components from mined ore. The author presents the influence of the centrifugal concentrator Nelson (Knelson) on increasing the degree of gold recovery from gold-bearing poor ores under high climatic conditions. Increase in gold production by the GRG test method due to the destruction of the ore structure and a significant decrease in density, as well as an increase in the opening of minerals using gravity up to 63 %. Thus, the optimization is classified as medium-coarse gold.

Gravity-flotation gold-bearing ore concentration

2021 ◽  
Vol 1 (1) ◽  
pp. 4-15
Author(s):  
P. K. Fedotov ◽  
A. E. Senchenko ◽  
K. V. Fedotov ◽  
A. E. Burdonov
Keyword(s):  
High Performance ◽  
Gold Recovery ◽  
Gold Content ◽  
Flotation Concentrate ◽  
Stage Scheme ◽  
Study Results ◽  
Ore Minerals ◽  
Concentrate Yield ◽  
Flotation Concentration ◽  
Gold Bearing

The paper focuses on the study of the gold-bearing ore dressability. According to technological research, the average gold content is 11.88 g/t. The silver content is insignificant – 2.43 g/t. Main ore minerals in the sample are pyrite and pyrrhotite. According to mineralogical and X-ray structural analysis, the average content of these minerals in the ore is about 6 % (in total). Main rock-forming minerals of the original ore are: quartz (60.1 %), quartz-chlorite-mica aggregates (3.8 %), carbonates (7.1 %). According to the study results, it was found that the gold recovery in the GRG test was 72.75 % with a total concentrate yield of 1.34 % and a content of 664.78 g/t. At the same time, the gold content in tailings was 3.29 g/t. A stage test showed that it is advisable to use a two-stage scheme for ore processing by gravity technology only. The first stage is in the grinding cycle with the 60–70 % ore size, and the second stage is with the final classifier overflow size of 90 % –0.071 mm. Centrifugal separation has high performance as a free gold recovery operation in the grinding cycle. A concentrate with a gold content of 2426 g/t was obtained with a yield of 0.31 % and a recovery of 63.74 %. The beneficiation of first stage tailings ground to 90 % –0.071 mm at the KC-CVD concentrator (modeling) made it possible to extract gold into a total gravity concentrate (KC-MD + KC-CVD) of 87.25 % with a concentrate yield of 22.63 %. The gold content in tailings was 1.97 g/t. The results of gravity and flotation concentration of the original ore indicate the feasibility of using a combined gravity-flotation technological scheme. In a closed experiment of the initial ore beneficiation according to the gravity-flotation scheme at a natural pH of the pulp (without adding acid), the following products were obtained: gravity concentrate with a gold content of 2426 g/t at a yield of 0.31 % and recovery of 64.06 %; flotation concentrate (after the II cleaning) with a gold content of 122 g/t at a yield of 2.90 % and recovery of 33.01 %; the total gold recovery in the gravity-flotation concentrate was 94.07 % with a yield of 3.21 % and an Au content of 345.87 g/t, the gold content in the flotation tailings was 0.72 g/t.

Fasteners at Low Temperatures: Characterization and Methods for Design

2011 ◽  
Author(s):  
Melanie Stephan ◽  
Jens O. Weber ◽  
Ulrich Wuttke ◽  
Christina Berger
Keyword(s):  
Impact Test ◽  
Freezing Point ◽  
Lattice Structure ◽  
Detailed Examination ◽  
Test Methods ◽  
Climatic Conditions ◽  
Test Method ◽  
Design Concepts ◽  
Ductile Behavior ◽  
Pendulum Impact

Bolted joints are a major part of wind energy plants. Due to climatic conditions, they are often exposed to temperatures far below the freezing point. Together with the multiaxial state of stress, which results from the notch effect of the thread, and possible dynamic overloads during operation, sufficient ductility of the material is needed. The state of the art method to investigate the ductile behavior of fasteners is the Charpy pendulum impact test with a V-notched specimen. According to international standard DIN EN ISO 898-1 [1] respectively ASTM F568M-07 [2], fasteners made of carbon steel and alloy steel with a body centered cubic lattice structure can be used for temperatures down to 223 K (−50°C, −58°F) as long as a minimum impact energy of 27 J at 253 K (−20°C, −4°F) is met. As there are several disadvantages in using this test method for fasteners, a detailed examination of existing test methods and design concepts is necessary to find alternatives to the Charpy pendulum impact test. Extensive quasi-static and dynamic material tests were conducted on fasteners with property classes 5.6, 10.9 and 12.9 in a temperature range between 203 K (−70°C, −94°F) and room temperature 293 K (20°C, 68°F). Both mechanical properties and the influence of different specimen geometries were evaluated. Analytical concepts for the description of the low temperature applicability of different steels were analyzed.

STALE GOLD-BEARING TAILINGS OF THE BALEIZOLOTO PLANT AND THE PROBLEM OF THEIR DISPOSAL

2021 ◽  
Vol 27 (4) ◽  
pp. 45-54
Author(s):  
G. Yurgenson ◽  
◽  
L. Shumilova ◽  
А. Khatkova ◽  
◽  
...  
Keyword(s):  
Negative Impact ◽  
Chemical Elements ◽  
Raw Materials ◽  
Precious Metals ◽  
Gold Content ◽  
Residential Areas ◽  
Extraction Technology ◽  
Useful Components ◽  
Technogenic Raw Materials ◽  
Gold Bearing

The relevance of the research is the need to recultivate the waste from the enrichment of gold-bearing ores that lie in the immediate vicinity of the residential areas of Baley city, which have a negative impact on the environmental situation in it, as well as to develop a technological approach to the extraction of gold and silver. The purpose of the study is to study the material composition and develop a technology for extracting precious metals. The object of the study is the stale tailings of the ZIF-1 plant “Baleizoloto”. The subject of the study is mineral composition of stale tailings, content of useful components and their extraction technology, the method and methodology presented by mineralogical and chemical analyses of enrichment tailings. Results. The analysis of the tailings dumps’ state of the gold recovery factories of the Baleizoloto plant was carried out. The contents of gold and other chemical elements, among which arsenic, zinc, copper, antimony, and lead predominate, were determined. The gold content prevails in the stale tailings of the ZIF-1 factory, which processed the ores of the Baley deposit, and is in the range of 1.09-1.37 g / t, on average – 1.17 g/t. This determines the prospects for their primary processing. The gold in the clay-sand fraction of the stale tailings is mainly found in thin accretions with quartz, carbonates, pyrite, arsenopyrite, sulfosols, and tellurides. The field of application is processing of technogenic raw materials. Conclusions. It was determined that the sizes of gold inclusions are in the range of 0.7-0.03 mm, the gold penetration varies from 63 to 91.15, and on average is 82.13; the main impurity in gold is silver with a content of 8.85-37%; the average silver content in the tailings of the ZIF-1 factory is 1.85 g/t; the recommended technological scheme for processing stale tailings of ZIF-1 of the Baleizoloto plant has been developed, including the following operations: photoelectron-activation preparation, pelletizing with active solution, heap leaching, two-stage sorption with bubbling with ozone

scholarly journals Metodología geometalúrgica para mejorar el proceso de extracción de oro en pequeña escala de la mina Gualconda en Nariño – Colombia

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Gabriel Kamilo Pantoja-Barrios ◽  
Eliana Katherine Molina-Ramírez ◽  
Silvia Natalia Fuentes-Torres ◽  
Fabian Andrés Ramírez ◽  
Jaime Mojica ◽  
...  
Keyword(s):  
Particle Size ◽  
Low Cost ◽  
Size Reduction ◽  
Gold Recovery ◽  
Small Scale ◽  
Operational Parameters ◽  
Particle Size Reduction ◽  
Mineralogical Characterization ◽  
Analytical Technique ◽  
Gold Bearing

In the gold beneficiation processes, the degree of particle size reduction is strongly influenced by the size and shape of the mineral species associated with the economically important metals. The capacity, energy consumption, and costs of the gold-bearing ore processing depend mainly on the operational parameters of the equipment of comminution and gravimetric concentration; therefore, it is essential to characterize the liberation degree of the minerals of interest as function of particle size. The small-scale mining beneficiation plants usually do not consider the liberation of sulfide particles as a requirement to define the grinding size reduction ratio, this is determined empirically, evaluating in which size a higherpercentage of gold recovery is obtained. The methodology proposed in this paper constitutes a low cost analytical technique, using the free software IMAGE-J, to determine the appropriate liberation size for sulfide particles and associated gold particles,as well as the size distribution of gold ore particles. Additionally, the Molycop-Tools software was used to simulate the best grinding strategy based on the liberation results obtained.Through the methodology of automatic image analysis to determine the liberation degree of sulfides, the mineralogical characterization, and the recommendation of a metallurgical processing strategy for the gold-bearing ore based on steady-state simulations, it was possible to establish the appropriate parameters of ball mill grinding and gravimetric concentration of the Gualconda mine in the Department of Nariño, in order to improve the gold recovery and increase the plant capacity.

Development of a combined processing technology for low-sulfide gold-bearing ores

2021 ◽  
pp. 3-8
Author(s):  
A. K. Koyzhanova ◽  
B. K. Kenzhaliev ◽  
D. R. Magomedov ◽  
N. N. Abdyldaev
Keyword(s):  
Raw Materials ◽  
Gold Recovery ◽  
Gold Content ◽  
Ministry Of Education ◽  
Gravity Concentration ◽  
Laboratory Equipment ◽  
Sorption Leaching ◽  
The Republic ◽  
Processing Circuit ◽  
Gold Bearing

This paper presents the results of laboratory dressability studies for low-sulfide gold-bearing ores using combined processing and subsequent oxidation leaching of the resulting combined concentrate. According to the current raw materials processing circuit used at the Sekisovskoye deposit, gravity concentration experiments were first carried out using the following laboratory equipment: a Knelson KSMD 3 centrifugal concentrator, an SKO-05 concentration table, and a two-chamber diaphragm jigging machine (i.e., OML by TsNIGRI). A significant portion (0.5 to 1.0 g/t) of the gold remains in the gravity concentration tailings. Subsequent flotation experiments for the tailings suggest that additional gold recovery is possible. The gold content in the final flotation tailings was in the range of 0.15–0.25 g/t. The final gold recovery in the combined process was therefore 93.7–96.5 %. The subsequent sorption cyanidation of the concentrate according to the current processing circuit allows depositing an average of 75.0–80.0 % Au on the coal. At the same time, the residual gold content in the sorption leaching tailings is significant and amounts to 3.6–7.5 g/t. The preliminary oxidation experiments for the concentrate slurry indicate the possibility of a more complete gold recovery with subsequent leaching, including sorption leaching. The residual gold content in the cakes was measured at 0.7–1.5 g/t, which ultimately yielded 95–96 % recovery at the leaching stage. The research was completed with the financial support of the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan under grant No. АР05130143.

scholarly journals Effect of Riffle Height and Spacing of a Sluice Board on Placer Gold Recovery

2017 ◽  
Vol 17 (1) ◽  
pp. 64-72
Author(s):  
G. Agyei ◽  
J. J. Gordon
Keyword(s):  
Cost Effective ◽  
Processing Technique ◽  
Gold Recovery ◽  
Small Scale ◽  
Mining Site ◽  
Placer Gold ◽  
Gold Particles ◽  
Artisanal Miners ◽  
The University ◽  
Gold Bearing

Sluicing is the preferred mineral processing technique for the treatment of placer gold-bearing alluvium for small scale and artisanal miners in Ghana because sluice board is perceived to be the most cost effective device. However, there are differences in approaches from design to operation.  In this work, about 50 kg of ore was obtained from “Peace School” small scale mining site near the University of Mines and Technology, Tarkwa. It was processed to determine the effects of riffle height and spacing on gold recovery. It was confirmed that, in order to trap a greater percentage of gold particles, the height of the riffle ought to be higher than the suspension height of the gold. The suspension heights of the gold particles of the various operational regimes of the sluice board at superficial velocities of 0.5 m/s, 1.0 m/s, 1.5 m/s and 2.0 m/ were   0.9 cm, 1.2 cm, 1.5 cm and 2.9 cm respectively. Analysis of concentrates showed that, 85.4% of gold was recovered during sluicing at approximately 1.0 cm riffle height.  The lowest recovery was recorded at 0.5 cm riffle height. Gold recovery was also affected by riffles spacing.  For the indicated speeds and the riffle heights the necessary spacing should not be more than 20 cm. The peak recovery was obtained at a riffle height of 1.0 cm but dropped after 20.0 cm spacing. Keywords: Sluice Board, Riffle Height, Gold, Rifle Spacing 

Dependence of uranium extraction into solution during heap leaching on the petrographic composition of ores

2021 ◽  
Vol 27 (7) ◽  
pp. 27-32
Author(s):  
V. Ovseychuk ◽  
Keyword(s):  
Raw Materials ◽  
Acid Leaching ◽  
Heap Leaching ◽  
Material Composition ◽  
Raw Material ◽  
Petrographic Composition ◽  
Uranium Extraction ◽  
Useful Components ◽  
Maximum Extraction ◽  
Productive Solution

The widespread introduction of physical and chemical geotechnologies in the production of mineral raw materials makes it possible to involve ores that are poor in the content of the useful component, which are unprofitable to work out using traditional physical and technical methods. One of these new geotechnologies is the heap leaching of rocky uranium ores. When planning the volume of output of finished products, it is necessary to have an analytical apparatus that would make it possible, using the acquired knowledge, to calculate the required volume of mineral raw material production and its varietal composition. Based on their task, studies were conducted on the qualitative and quantitative characteristics of ores that affect the indicators of extraction of useful components from them. As a result of the research, the dependence of the index of uranium extraction into a productive solution during infiltration of sulfuric acid leaching on the material composition of ores was established. Ores localized in various lithological differences of acidic, medium and basic rocks were tested: granites, felsites, trachydacites, andesites and conglomerates. The ores were classified according to the size of the piece with the allocation of fineness classes +200 mm, -200 +150 mm, -150 + 100 mm, -100+70 mm, -70+ 30 mm, -30 mm. The tests were carried out in laboratory and semi-industrial conditions. The maximum extraction was obtained for the class – 30 mm in columns. When leaching in stacks, the maximum extraction of uranium into the solution was obtained for the size class -70+30 mm. The reason for the lower extraction from the -30 mm class during leaching in semi-industrial conditions was the processes of mechanical colmatation, due to the large number of fine fractions. The criterion characterizing the material composition of ores is the content of silica (SiO2). During the tests, the dependence of the uranium extraction coefficient in the productive solution on the content of silica in the ores was established. The higher the concentration of silica, the more uranium passes into the productive solution during leaching with a stable composition of uranium mineralization. The dependence is described by a mathematical formula, which allows us to use it to calculate the extraction of uranium into a productive solution, knowing the material composition of ores

Sign in / Sign up

Export Citation Format

Share Document