Since the copper grade is very low and the deposit contains significant amounts of arsenic, the traditional flotation and smelting process cannot be applied to extract copper economically and effectively, and in 1998 the mine operators began extracting copper using heap bioleaching (Ruan et al. 2006). Due to the relatively warm climate (average ...
Considering the extraction of Au from refractory ores as an example, it has been seen that without pretreatment, the recovery of Au with the conventional leaching process (cyanidation) is less than 50% but with bioleaching, the recovery rates increase to more than 95% depending on the mineral composition of the ore and on the extent of pre ...
The interaction between microorganisms and minerals was a hot topic to reveal the transformation of key elements that affecting bioleaching efficiency. Three typical lowgrade copper ores, the main copperbearing components of which were primary sulfide, secondary sulfide and highoxidative sulfide copper, were obtained from Dexing, Zijinshan ...
The use of biotechnology to explore lowgrade ore deposits and mining tailings is one of the most promising alternatives to reduce environmental impacts and costs of copper extraction. However, such technology still depends on improvements to be fully applied in Brazil under industrial scale. In this way, the bioleaching, by Acidithiobacillus ferrooxidans, in columns and stirred reactors were ...
Microbial ore leaching (bioleaching) is the process of extracting metals from ores with the use of microorganisms. This method is used to recover many different precious metals like copper, lead, zinc, gold, silver, and nickel. Microorganisms are used because they can: lower the production costs. cause less environmental pollution in comparison ...
net reaction: (4) In general, sulfides are first oxidized to elemental sulfur, whereas disulfides are oxidized to give thiosulfate, and the processes above can be applied to other sulfidic ores. Bioleaching of nonsulfidic ores such as pitchblende also uses ferric iron as an oxidant (, UO 2 + 2 Fe 3+ ==> UO 22+ + 2 Fe 2+ ).
Biofilm formation within the process of bioleaching of copper sulfides is a relevant aspect of iron and sulfuroxidizing acidophilic microorganisms as it represents their lifestyle in the actual heap/dump mining industry. Here, we used biofilm flow cell chambers to establish laminar regimes and compare them with turbulent conditions to evaluate biofilm formation and mineralogic dynamics ...
Bioleaching refers then to the process of extracting metals from ores using natural materials present in the environment, such as water, air, ... Sidborn et al., on the other hand, developed a model for representing the process of bioleaching of secondary copper ores from a heap leach. It was considered that the aeration of the heap is ...
Finite reserves of copper ores are becoming scarce and new ways of extracting copper from lowgrade ores include phytomining, and bioleaching. Low grade ores only contain small concentrations of copper and would not normally be considered economic to mine and process, as would waste material from processing high grade copper ores.
Bioleaching is commonly used to extract copper from the lowgrade ores or coppercontaining wastes due to the merits of environmentally friendliness and low cost (Yin et al., 2019a, Yin et al., 2021a; Li et al., 2014), however, bioleaching is impeded by its sluggish reaction kinetics (Yu et al., 2020; Guezennec et al., 2017).
In this regard, the present work assessed the bioleaching of two chalcopyrite ores—containing % Cu (copper ore 1) and % Cu (copper ore 2) by the extreme thermophilic archaea Sulfolobus acidocaldarius. In addition, the effect of different NaCl concentrations ( − mol/L) on copper extraction were investigated.
Heap leaching. Heap leaching is another common method used to extract copper from lowgrade ore. The process involves placing the ore on a lined pad and then sprinkling it with a solution that contains sulfuric acid. The acid leaches the copper out of the ore and into the solution, which is then collected and processed to concentrate the copper.
Spasova et al. (2006) examined the extraction of copper, gold, and silver from a heap consisting of five tons of polymetallic sulfide ore that had been crushed to less sizes than 10 mm. The main copperbearing mineral of the ore was chalcopyrite, while secondary copper sulfides, such as covellite and bornite, also were present.
Although bioleaching is used commercially to process copper, zinc, nickel and cobalt ores, ... Post bioleaching process the extraction of metals is a crucial and complex procedure. Due to no. of metals and nonmetals embedded over the waste material, a multicomponent solution is obtained. Therefore, the extraction of target metals is a ...
Lowgrade ores generated by mining activities can lead to resource waste and environment pollution, which is of great concern. Thus, lowgrade copper sulfide ores bioleaching is investigated in this study by reinoculating bacteria at different intervals. The highest bacteria concentration of × 107 cells·mL−1, improved attached bacteria proportion of % and copper recovery of 68 ...
This paper provides an overview of hydrometallurgical copper extraction studies in which liquid extraction technology has been used with four copper deposits of different compositions. The sulfuric acid consumption rate and copper extraction efficiency, which are dependent on the initial content and forms of calcium compounds and other impurities in ore samples, were calculated, and the ...
On a former Air Force base in Louisiana, Ucore Rare Metals aims to process rare earths by mid2025 using a technology known as RapidSX that it says is at least three times faster than solvent ...
Biofilm formation within the process of bioleaching of copper sulfides is a relevant aspect of iron and sulfuroxidizing acidophilic microorganisms as it represents their lifestyle in the actual heap/dump mining industry.
This paper reports on a study of column bioleaching of a lowgrade chalcopyrite ore that is currently dumpleached under natural biological conditions without any control over microbial populations. The experimental methodology was focused on the effect of managing the bacterial populations in a raffinate solution sourced from a dumpleach operation. This study presents results from columns of ...
In bioleaching, bacteria are used to extract copper ions from low grade copper this process, bacteria convert copper compounds within ores into copper compound solutions are called the leachate and can be separates using electrolysis or displacement reactions to form copper metal.. Bioleaching has the advantage of being a relatively green process.
Copper (Cu) extraction and processing is one of the most important mining activities around the world. ... Initially during this process, lowgrade Cu ores (with less than 2% Cu content) are ground and crushed. ... José Antonio, Jennyfer Serrano, and Eduardo Leiva. 2018. "Bioleaching of ArsenicBearing Copper Ores" Minerals 8, no. 5: 215 ...
Extraction processes for secondary copper sulfides and lowgrade ores includes the process of heap bioleaching. Heap bioleaching presents a cost efficient extraction method that requires a less intensive energy input resulting in a higher profit. This extraction process can be applied to large quantities of lowgrade ores, at a lower capital ...
Fig. 6 shows a twostage pilotscale heap bioleaching process to extract copper, gold, and silver from a polymetallic sulfide ore using biosolutions containing acidophilic chemolithotrophic bacteria for copper bioleaching, and containing microbial protein hydrolysate, thiosulphate, and copper and sulfite ions for gold and silver bioleaching ...
The increase of the temperature leads to an increase of copper extraction rates from lowgrade copper ore as shown in Fig. 4. A maximum of % Cu was recovered at 60°C as compared to other three temperatures % at 40°C, % at 50°C and % at 60°C respectively. Copper dissolution was higher at 60°C than at 50 or 40°C.
There are large quantities of such lowgrade ores especially copper ores, which can be processed profitably by bioleaching. Copper and Uranium are presently produced commercially by employing bioleaching process.
It is divided in two parts, the fundamentals and the practical aspects of this technology, and includes (i) the principles of bioleaching chemistry, (ii) data regarding bioleaching...
These processes have been applied to heap and tank leaching, nowadays termed biomining, but increasing concerns about the social acceptance of mining has also seen the reemergence of in situ leaching and quest for broader applicability beyond uranium and copper.
The bioleaching process resulted in 98% (copper) and 82% (nickel) at 30 °C (160 rpm) within 72 h. ... (zinc), 64% (aluminum), 86% (copper), and 74% (nickel) were obtained. A higher copper extraction of 85% at 50 °C in 8 d by Sulfobacillus ... Kaksonen, Bioleaching of gold from sulfidic gold ore concentrate and electronic waste by ...
Bioleaching is a simple and effective technology for metal extraction from lowgrade ores and mineral concentrates. Metal recovery from sulfide minerals is based on the activity of chemolithotrophic bacteria, mainly Thiobacillus ferrooxidans and T. thiooxidans, which convert insoluble metal sulfides into soluble metal ores and minerals can be treated by heterotrophic ...
Abstract. In copper dump leaching, runofmine ore is irrigated with acidic leaching solution to generate aqueous cupric ions for further processing. The very large size of the ore particles being leached, as much as two meters in diameter, should preclude any significant metal recovery. Dump leaching should not work; and yet it does.
Overall, some 20% of the world's copper production comes from bioleaching. The practice is not limited to copper. Microorganisms are also used to extract gold and uranium.
Dump leaching was popularly used for the extraction of copper sulfide ores (Brierley 2008). Heap Leaching. Heap bioleaching is a speedily rising method for the extraction of base metals from sulfide minerals. Bioheaps are a big amount of lowgrade ores and effluents from extraction strategies that include trace quantities of minerals.
Additionally, for gold and copper extractions, bioleaching is used to extract cobalt, zinc, nickel, and uranium from lowgrade ores and industrial effluents. In this review, the fundamental process of bioleaching from lowgrade metal sulfide ores are discussed with emphasis on mechanism, types, pathways, techniques, and bioleaching development.
Bacterial community dynamics and copper leaching with applied forced aeration were investigated during lowgrade copper sulphide bioleaching to obtain better bioleaching efficiency. Results illustrated that appropriate aeration improved bacterial concentrations and leaching efficiencies. The highest bacterial concentration and Cu2+ concentration after 14d leaching were × 107 cells·mL ...
Now, miners aim to use bacteria or other newly developed chemicals to extract even more copper from that waste rock in a secondary leaching process. That could enable them to produce copper at ...
© DZCrusher - كل الحقوق محفوظة
