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It was observed that the highest percentages of bioleached uranium from the tested samples directly by Penicillium purpurogenium and Pseudomonas fluorescens SHA 281 were found to be 72.49, 55.49 and 60.06 %, respectively. Uranium (U) is one of the strategic elements and essential for many applications as a fuel in nuclear power plants and nuclear weapons. …
WhatsApp: +86 18221755073Microbiological leaching has been use as an alternative approach to conventional hydrometallurgical methods of uranium's extraction. In the microbiological leaching process, iron-oxidizing bacteria oxidize pyretic phase to ferric iron and sulfuric acid, and uranium is dissolved …
WhatsApp: +86 18221755073Later, attempts for in situ recovery of base metals have been undertaken. In the in situ leaching process, a leaching solution is injected into a subsurface ore body where valuable metals such as uranium or copper are dissolved from the ore. The pregnant leach solution (PLS) is pumped to the surface where metal extraction takes place.
WhatsApp: +86 182217550732016. Uranium (U) is one of the strategic elements and essential for many applications as a fuel in nuclear power plants and nuclear weapons. Microbiological leaching has been used as an alternative approach to conventional hydrometallurgical methods of uranium's recovery from low grade ores and waste samples Penicillium purpurogenium and Pseudomonas fluorescens …
WhatsApp: +86 18221755073The thin-layer leaching process originally conceived and developed for leaching oxide ores has been successfully adapted to bacterial leaching of mixed and secondary sulphide ores.
WhatsApp: +86 18221755073Uranium is bioleached from ores in acidic ferric sulfate lixiviant. Ferric iron oxidizes tetravalent uranium to the hexavalent form and is thereby reduced to ferrous iron in this redox …
WhatsApp: +86 18221755073CONTENTS 3.1 Introduction 3.2 Uranium Leaching Methodologies 3.2.1 Chemical Leaching 3.2.2 Bioleaching 3.3 Modes and Mechanism of Uranium Bioleaching 3.3.1 Direct Mechanism 3.3.2 Indirect Mechanism 3.3.3 Bioleaching by Heterotrophs 3.4 Factors Influencing Bioleaching 3.4.1 Mineralogy of the Ore 3.4.2 Microorganisms 3.4.3 Temperature 3.4.4 pH …
WhatsApp: +86 18221755073The feasibility of sulfur enhancement for uranium bioleaching in column reactors was assessed with a designed mixed Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Leptospirillum ferriphilum from a refractory uranium ore. The uranium extraction reached 86.2% with the sulfur enhancement (1 g/kg) in 77 days leaching process, increased by 12.6% …
WhatsApp: +86 18221755073Microbiological leaching has been used as an alternative approach to conventional hydrometallurgical methods of uranium extraction. In the microbiological leaching process, iron-oxidizing bacteria oxidize pyritic phases to ferric iron and sulfuric acid, and uranium is solubilized from the ore due to sulfuric acid attack. If uranium in the ore material is in the reduced, …
WhatsApp: +86 18221755073Bioleaching or microbial leaching: This broadly involves the extraction or solubilization of minerals from the ores by the microorganisms. 2. Bio-sorption: It deals with the microbial cell surface adsorption of metals from the mine wastes or dilute mixtures. ... (FeS2) within the uranium ore. For optimal extraction of uranium by bioleaching ...
WhatsApp: +86 18221755073Uranium, an essential source of nuclear fuel, has been increasingly applied in electricity generation and defense industry [1,2,3].Bioleaching, as an economical and eco-friendly metallurgical method [1, 2], has been identified to be one of the alternatively available ways for uranium extraction from the complex and refractory or low-grade ores using stirred tank …
WhatsApp: +86 18221755073Microbiological leaching of uranium ores. Olli Tuovinen. 1999, Mining, metallurgy & exploration. See full PDF download Download PDF. Related papers. Mineral Processing and Extractive Metallurgy Review: An International Journal Microbially Assisted …
WhatsApp: +86 18221755073Microbiological activity inside the heap is conditioned by its mineral composition and environmental and operational factors must also be taken into account. The industrial …
WhatsApp: +86 18221755073In biological leaching processes, for instance, as described in studies such as Abnilash et al.'s "Bioreactor Leaching of Uranium from Low-Grade Indian Silicate Ore," the optimal density of the "pulp" plays a crucial role in enhancing the efficiency of uranium extraction. Maintaining the pulp density at 20–40% ensures optimal ...
WhatsApp: +86 18221755073Microbial Leaching of Uranium Ore. Written By. Hadi Hamidian. Submitted: 24 October 2010 Published: 09 September 2011. DOI: 10.5772/17941. DOWNLOAD FOR FREE. Share. Cite IntechOpen. Nuclear Power Deployment, Operation ...
WhatsApp: +86 18221755073Bioleaching of uranium was carried out with Turamdih ore sample procured from Uranium Corporation of India Limited, Jaduguda. The bacterial strain that was used in the leaching experiments was isolated from the Jaduguda mine water sample. Efficiency of bioleaching was studied by varying parameters like pulp density and initial ferrous …
WhatsApp: +86 18221755073The column leaching experiments included two phases, acidic pre-leaching and microbial leaching (Yang et al., 2022). The column leaching turned into bioleaching phase when pH of the leaching liquor was at approx. 3.0. ... (2.79%) of the raw ore was sufficient for leaching of uranium. However, it would be transferred into jarosite on the surface ...
WhatsApp: +86 18221755073Uranium is one of the strategic elements and is used as a fuel in nuclear power plants. The application of microorganisms in the recovery of uranium can effectively reduce investment cost, improve uranium recovery and shorten the leaching cycle [1, 2].Bacterial leaching of uranium with chemoautotrophic bacteria has been extensively studied, including …
WhatsApp: +86 18221755073A bacterial leaching program was carried out in order to evaluate the potential of applying this process to leach uranium from the ore of Figueira—PR, Brazil. The experiments were carried out in shake flasks, column percolation …
WhatsApp: +86 18221755073In this study, an experimental column system is used to emulate the heap leaching process but on a much smaller and controlled scale in order to evaluate the leaching biogeochemistry of a non-sulfidic ore. An indigenous, active microbial community was prepared by concentrating biomass derived from the uranium extraction process from the Ranger ...
WhatsApp: +86 18221755073Indirect Bacterial Leaching (Non- contact leaching) In Indirect bacterial leaching, no direct contact between the microorganisms and the mineral occurs. ... The bacteria, particularly T. ferrooxidans, do not directly attack the …
WhatsApp: +86 18221755073Bioleaching and ore mineralogy Although there has been no definitive study of the influence which the type of uranium ore has on bacterial leaching, the literature [ 35,36 ] suggests that the pyrite content of the ore is of fundamental importance. For this reason, this type of attack has not been widely used in the extraction of uranium from ...
WhatsApp: +86 18221755073ISL uranium mining is mainly divided into three types: acid in-situ leaching, alkaline in-situ leaching and CO 2 +O 2 in-situ leaching. In acid in-situ leach (AISL) mining, U(IV) minerals undergo oxidation by H 2 O 2 or Fe 3+ to generate highly soluble uranyl sulfate species [UO 2 (SO 4 ) 2 ] 2- or [UO 2 (SO 4 ) 3 ] 4-, with the process being ...
WhatsApp: +86 18221755073A bacterial leaching program was carried out in order to evaluate the potential of applying this process to leach uranium from the ore of Figueira-PR, Brazil. The experiments were carried out in shake flasks, column percolation (laboratory and scmipilot scale)and in …
WhatsApp: +86 18221755073Uranium is an important strategic resource, which is mainly extracted from uranium ore. Acid leaching is the most commonly used uranium extraction technique, with sulfuric acid used as the leaching agent and MnO 2 or NaClO 3 used as the oxidants [].As the hard rock type high-grade uranium resources in southern China is gradually decreasing and the mining depth …
WhatsApp: +86 18221755073• Bioleaching, or microbial ore leaching: is a process used to extract metals from their ores using bacterial micro-organisms. • The bacteria feed on nutrients in the minerals, causing the metal to separate from its ore. • The metals commonly extracted using this process include gold, silver, zinc, copper, lead, arsenic, antimony, nickel ...
WhatsApp: +86 18221755073IN–SITU LEACHING: • Ore remains in natural state while leaching process takes place. ... oxide in order to leave the iron behind. • Acidithiobacillus ferrooxidans are used as bacterial agents. • Maximum extraction occurs at pH 1.3 Fe2O3+3CO 2Fe+3CO2 ... (FeS2) in uranium ore and produces ferric sulphate and sulphuric acid • The ...
WhatsApp: +86 18221755073Uranium (U) is one of the strategic elements and essential for many applications as a fuel in nuclear power plants and nuclear weapons. Microbiological leaching has been used as an alternative ...
WhatsApp: +86 18221755073Compared with traditional leaching methods for uranium ore [3], the bioleaching method has demonstrated the advantages of low cost and improved environmental safety and has been shown to be a ...
WhatsApp: +86 18221755073
We evaluated uranium bioleaching from low-grade, granite-type uranium ore using mixed acidophilic microbes from uranium mine leachate. A 4854-ton plant-scale heap bioleaching process achieved sustained leaching with a uranium leaching efficiency of 88.3% using a pH of 1.0–2.0 and an Fe3+ dosage of 3.0–5.5 g/L. Acid consumption amounted to 25.8 g H2SO4 …
WhatsApp: +86 18221755073characteristics of the individual ore, i.e. the leaching conditions have to be established for each type of ore. The solubilization of uranium is an indirect bacterially catalyzed process. In the present paper investigations on the applicability of bacterial leaching of sedimentary uranium ore from Forstau (Austria) are described.
WhatsApp: +86 18221755073Leaching rate of uranium from exhausted ore depended on both sulfuric acid concentration and microbial activity of bacteria isolated from acid mine drainage, formed on uranium deposit.
WhatsApp: +86 18221755073Uranium Leaching •Uranium leaching is an indirect process. •When T.ferroxidans are involved in uranium extraction, they do not directly attack on ore but on the iron oxidants. •The pyrite reaction is used for the initial production of Fe Reaction: 2FeS + …
WhatsApp: +86 18221755073Microbial Leaching of Uranium Ore. Written By. Hadi Hamidian. Submitted: 24 October 2010 Published: 09 September 2011. DOI: 10.5772/17941. DOWNLOAD FOR FREE. …
WhatsApp: +86 18221755073The use of heterotrophic fungi (strains of Aspergillus and Penicillium) and bacteria (strains of Bacillus and Pseudomona) for metal recovery have been extensively studied.However, in case of nickel recovery from lateritic ores, strains of Aspergillus and Penicillium are the most preferred microorganisms.Acidithiobacillus ferrooxidans a chemolithotrophic bacterium has …
WhatsApp: +86 18221755073The bacterial strain that was used in the leaching experiments was isolated from the Jaduguda mine water sample. Efficiency of bioleaching was studied by varying parameters like …
WhatsApp: +86 18221755073The optimal microbial leaching conditions with a mixed bacterial strain (Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans) for microwave-treated uranium ore were: pH of 1.58, pulp density of 10.11 %, Fe 2+ concentration of 3.67 g/L (Liu et al., 2021). Microwave treatment is proved to be an effective method to damage gangue ...
WhatsApp: +86 18221755073The invention provides a bacterial leaching method for refractory uranium ores, and belongs to the technical field of biological metallurgy. The method comprises the following steps: mixing sulfur powder into uranium ore, and performing acid leaching by using a sulfuric acid solution to obtain an adsorption tail solution; inoculating the domesticated and cultured compound bacterial liquid …
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