Biomining and Bioleaching SARDAR HUSSAIN In . Bioleaching where microorganisms are used to facilitate the mining of metals. For biomining specialized microorganisms are used in order to recover valuable metals from ores via bioleaching. Important leaching bacteria are aerobic. Microbial Leaching (Bioleaching, Biomining). Microbial leaching is the process by which metals are dissolved from ore bearing rocks using microorganisms.
|Published (Last):||14 September 2005|
|PDF File Size:||12.57 Mb|
|ePub File Size:||13.26 Mb|
|Price:||Free* [*Free Regsitration Required]|
Current Opinion in Biotechnology.
Use the lead layout guide to ensure the section follows Wikipedia’s norms and to be inclusive of all essential details. This risk can be managed by ensuring that biomining is conducted under controlled conditions with proper sealing and waste management protocols. Views Read Edit View history. The company simply collects the ions out of the solution after the bacteria have finished.
In the industrial microbial leaching process popularly known as bioleachinglow grade ore is dumped in a large pile the leach dump and a dilute sulfuric acid solution pH 2 is percolated down through the pile.
Can we mitigate environmental impacts from mining? Pyrite leaching FeS 2: This page was last edited on 15 Decemberat Not to be confused with Bioprospecting. In the microbial leaching process A. From Wikipedia, the free encyclopedia. This is the basic process behind most biomining, which is used for metals that can be more easily recovered when dissolved than from the solid rocks.
Some biomininng of past projects in biotechnology include a biologically assisted in situ mining program, biodegradation methods, passive bioremediation of acid rock drainage, and bioleaching of ores and concentrates. Bioremediation is not specific to metals. World Journal of Microbiology and Biotechnology. Iron-and sulfur-oxidizing microorganisms are used to release copper, gold and uranium from minerals. Fungi can be grown on many different substrates, such as electronic scrapcatalytic convertersand fly ash from municipal waste incineration.
Bioleaching – Wikipedia
The copper can also be concentrated and separated by displacing nad copper with Fe from scrap iron:. Furthermore biomining is applied for the recovery of gold, cobalt, nickel, zinc and uranium. Other uses of biomining New biomining techniques that do not involve oxidation are being tested, which would enable large-scale biomining for different types of minerals and metals. Most current biomining operations use naturally occurring microbial communities.
Applied and Environmental Microbiology. Heap or dump bioleaching, tank bioleaching, in situ or in place bioleaching. Some microbes bioleacning oxidize those metals, allowing them to dissolve in water. The ore minerals of the metals copper, nickel, cobalt, and zinc occur in nature mainly as metal sulfides.
In industrial bioleaching biomining three technical processes are differentiated: In this case, the lower cost of bacterial leaching outweighs the time it takes to extract the bio,ining. April Learn how and when to remove this template message. However, this process can also be usefully exploited when controlled.
During metal sulfide oxidation sulfur compounds and elemental sulfur occur. These microorganisms actually gain energy by breaking down minerals into their constituent elements.
Biomining: metal recovery from ores with microorganisms.
This yields soluble products that can be further purified and refined to yield the desired metal. Implementation of biological and chemical techniques to recover metals from copper-rich leach solutions. For biomining specialized microorganisms are used in order to recover valuable metals from ores via bioleaching. The sulfur containing ore pyrite FeS 2 is at the start of this process.
Upon further acidification Ferroplasma will also develop and further acidify. What happens before, during, and after mining?
What is biomining?
Several smaller operations recover metals from existing acid mine drainage. As a consequence of the microbial activity energy producing reaction:.
A different biomining technique, for metals which are not dissolved by the microbes, uses microbes to break down the surrounding minerals, making it easier to recover the metal of interest directly from the remaining rock.
The microbial oxidation process occurs at the cell membrane of the bacteria.
The lead section of this article may need to be rewritten. It is used most frequently when the percentage of the desired metal in a rock is small, or to extract remaining metals from waste rock after conventional mining.
The most common processes used in biomining are: The development of industrial mineral processing has been established now in several countries including South AfricaBrazil and Australia. Effect of elevated pressure on ferric iron reduction coupled to sulfur oxidation by biomining microorganisms. The temperature inside the leach dump often rises spontaneously as a result of microbial activities.
Valuable metals are commonly bound up in solid minerals. Economically it is also very expensive and many companies once started can not keep up with the demand and end up in debt. Bioreactor for metal bioleaching in the geomicrobiology laboratory of BGR Source: Gold is frequently found in nature associated with minerals containing arsenic and pyrite.
Companies can now grow large chemostats of microbes that are leaching viomining from their media, these vats of culture can then be transformed into many marketable metal compounds. Using Bacteria such as Acidithiobacillus ferrooxidans to leach copper from mine tailings has improved recovery rates and reduced operating costs. The liquid is then pumped back to the top of the pile and the cycle is repeated.
Traces of precious metals such as gold may be left in the original solution.