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Small-Scale Bioremediation Experiments in the Lab

Bioremediation is used in the field of biotechnology and is the process of overcoming environmental problems using biological means. Important applications include cleaning petroleum-contaminated soil, tetrachloroethene-affected land and oil-spill affected areas. Always before full-scale, environmental usage, the bioremediation options and methodologies are tested in situ, in the laboratory. It is interesting to note that the first organism ever patented was a genetically-engineered oil-degrading organism.

  1. Bio-cell and Bio-pole Designs

    • Environmental conservationists developed bio-cell and bio-pole technology to overcome the problem of petroleum contamination in soils, a major global issue. Although applied to soil areas of up to 30 to 100 yards cubed, according to the Department of Environmental Conservation (DEC), early experiments were conducted on small samples using indigenous (naturally-existing) microorganisms. Optimal pH values for petroleum-consuming microorganisms are 7, although a small amount of lime may be required to achieve this. Operating temperatures of between 40 and 100 degrees Fahrenheit are required.

    Tetrachloroethene-Affected Site Approaches

    • Even if it is occurring and accumulating naturally, tetrachloroethene (and its related compounds) requires removal from the environment. Bioremediation solutions are first developed and tested in the laboratory before scale-up is achievable. New Bio-Trap samplers using in situ microorganisms are used to evaluate the clean-up. A biostimulation "pilot test" is then carried out. Concentrations of accumulated by-product cis-dichlorethane ranged from 10 to 100 mg/L, as reported by Microbe. After testing, a high-performing solution is selected, such as HRC (hydrogen releasing compound) injection into affected soil or land.

    Oil Spill Clear-up Operations

    • Even huge and damaging oil-spills need laboratory bioremediation testing prior to successful clearing. According to Florida Sea Grant, the total oil spilled in the 2010 Gulf of Mexico oil-spill was estimated to be between 600 and 4,000 meters cubed. In addition to the technique used in petroleum-contamination removal using bio-cells and bio-poles, a process called "seeding" is carried out, where naturally-occurring microorganisms are added to samples of contaminated water. The microorganisms cause increased biodegradation in mass-culture laboratory experiments or in on-site bioreactors. Seeding with efficient degrading organisms reduces oil in controlled laboratory conditions, but it has yet to be tested and evaluated on large-scale operations in open water.

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