Bioremediation: Microorganisms Cleaning the Environment
Background
What is Bioremediation?
Bioremediation is a cost-effective and natural approach to cleaning up corrupted soil and groundwater through biological agents such as bacteria, microbes, fungi, and other organisms or their enzymes. Technologies can be categorized as in situ or ex situ. In situ bioremediation includes treating the contaminated material on site, while ex situ is the removal of the affected material from its contaminated location to be handled elsewhere.
The bioremediation process requires two key factors:
1) Electron donor: usually hydrogen - which can be taken from a carbon source such as an oil, such as vegatables or even lactate.
2) Electron Acceptor: an oxidate agent like oxygen. However, any microorganisms are capable of using other agents such as nitrate, sulfate or even a chlorinated solvent (PCE or TCE).
Electron donor or electron acceptor are either roles the contaminant can play in. (B1, B2).
Why is it important?
Bioremediation has proven to be an effective remediation technology:
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It mobilizes naturally-occurring biogeochemical processes
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Rather than transfering contaminants from one environmental media to another, it destroys or immobilizes it instead
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Protects limited resources due to compressed cleanup times and/or lower capital costs relative to many other remediation machinery (B3).
Principles of Bioremediation
Environmental biotechnology is not a new field; two examples of older environmental biotechnologies are composting and wastewater treatment. Newer studies in molecular biology offer new insights to opportunities for more productive biological processes. Some developments of note in these studies include cleaning up polluted water and land areas. In order for bioremediation to be efficient, microbes must transform pollutants in to a nontoxic product. Because bioremediation is only effective where microbes can grow and thrive, its use usually requires the manipulation of the environment to allow microorganisms to grow and degrade pollutants at a quicker rate. (B4)
Microbial Populations For Bioremediation Processes
Microorganisms can be confined to almost any environmental position. Microbes are able to grow accustomed to most conditions, including desert conditions and low temperatures. Also they can adapt to anaerobic conditions, with the presence of dangerous compounds or on any waste stream. Carbon and energy sources are the main requirements for these populations. Because of the adaptability of microbes and other biological systems, they may be used to degrade or remediate environmental risks. (B4)