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):||3 May 2017|
|PDF File Size:||4.87 Mb|
|ePub File Size:||19.21 Mb|
|Price:||Free* [*Free Regsitration Required]|
Enhanced chalcopyrite dissolution in stirred tank reactors by temperature increase during bioleaching. This oxidation relies on a combination of chemically and microbiologically catalyzed processes.
Adding concentrated acid reverses the equation, and the copper ions go back into an aqueous iboleaching. Biotechnology Economic geology Metallurgical processes Applied microbiology. This risk can be managed by ensuring that biomining is conducted under controlled conditions with proper sealing and waste management protocols.
Recent Advances in Acidophile Microbiology: Some examples 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.
Biomining is the use of microorganisms to leach metals from their growth medium. Some past projects include in situ mining, biodegradation, bioremediation, and bioleaching of ores.
It was discovered in the mid s that microorganisms use metals in the cell. The process for copper is very similar, but the efficiency and kinetics depend on the copper mineralogy. Populations of bacteria and archaea were used to rejuvenate the coast after the oil spill. This is shown in this figure. Microbes can achieve things at a chemical viomining that could never be done by humans. In general, sulfides are first oxidized to elemental sulfur, whereas disulfides are oxidized to give thiosulfateand the processes above can be applied to other sulfidic ores.
Biomining is the process of using microorganisms microbes to extract metals of economic interest from rock ores or mine waste. From in situ mining to mineral processing and treatment technology, biotechnology provides innovative and cost-effective industry solutions. Retrieved from ” https: The very first recognized biomining system was published in when Kenneth Temple PhD discovered that Acidithiobacillus ferrooxidans thrives in iron, copper and magnesium rich environments.
Companies can now grow large chemostats hioleaching microbes that are leaching metals from their media, these vats of culture can then be transformed into many marketable metal compounds. Languages Deutsch Edit links. 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.
From Wikipedia, the free encyclopedia.
Biomining: metal recovery from ores with microorganisms.
Via targeted research and further development of bioleaching valuable substances such as economically critical metals could be recovered from mine waste dumps mine tailingscomplex ores, non-sulfidic ores such as laterites and manganese nodules, as well as industrial residues such as ashes, sludges, slags and even electronic waste. Iron-and sulfur-oxidizing microorganisms are used to release occluded coppergold and uranium from mineral sulfides. Gold is frequently found in nature associated with minerals containing arsenic and pyrite.
An electric current is passed through biominihg resulting solution of copper ions. 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.
At the current time, it is more economical to smelt copper ore rather than to use bioleaching, since the concentration of copper in its ore is in general quite high.
These metal extractions can be performed in situ or ex situ where in situ is preferred since it is less expensive to excavate the substrate. Other metals, like gold, are not directly dissolved by this microbial process, but are made more accessible to traditional mining techniques because the minerals surrounding these metals are dissolved and removed by microbial processes.
What happens before, during, and after mining? In addition, an overview is given about metal sulfide oxidizing microorganisms, fundamentals of biomining including bioleaching mechanisms and interface processes, as well as anaerobic bioleaching and bioleaching with heterotrophic microorganisms. The electrons lost by the iron are taken up by the copper.
Bioleaching is a conversion of an insoluble valuable metal into a soluble form by means of microorganisms.
Biomining – Wikipedia
This step is entirely independent of microbes. Fungi can be grown on many different substrates, such as electronic scrapcatalytic convertersand fly ash from municipal waste incineration. In addition to copper and gold production, biomining is also used to produce cobalt, nickel, zinc, and uranium. The ore minerals of the metals copper, nickel, cobalt, and zinc occur in nature mainly as xnd sulfides.