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Environmental biotechnology is the use of nature, in the form of plants, animals, bacteria, fungi and algae, to produce renewable energy, food and nutrients in a cycle. In this cycle the waste of each process becomes the feedstock for another process.

Today biotechnology can not only help clean up environmental messes but also keep problems from developing. It can do everything from keeping the water clean in your area to helping the world to stop global warming.

Bioremediation techniques can be used to reduce or to remove hazardous waste which has already polluted the environment. ("Remediate" means to solve a problem, and "bio-remediate" means to use biological organisms to solve an environmental problem such as contaminated soil or groundwater). They are also used to clean waste water before it leaves production facilities. Micro-organisms in sewage treatment plants remove pollutants from waste water before it is discharged into rivers or the sea. Industrial and agricultural pollution needs processes that remove specific pollutants such as nitrogen and phosphorus compounds, heavy metals and chlorinated compounds. The costs of waste water treatment can be reduced by the conversion of wastes into useful products. For example, heavy metals and sulphur compounds can be removed from waste streams by the aid of sulphur metabolizing bacteria and reused. Another example is the production of animal feed from the fungal biomass which remains after the production of penicillin. Most anaerobic waste water treatment systems produce useful biogas.

Air and waste gases: Originally, industrial waste gas treatment systems were based on cheap compost-filled filters that removed odours. Such systems still exist. However, there are better methods such as bio scrubbers, in which the pollutants are washed out using bio trickling filters, in which the pollutant is cleaned by micro-organisms.

Soil and land treatment: The soil may be treated in soil banks, or in specialized bioreactors. Groundwater is treated in bioreactors and either pumped back into the ground or drained into surface water. Bioremediation of land is often cheaper than physical methods.

Process improvement: Many industrial processes have been made more environmentally friendly by the use of enzymes. Enzymes are biological catalysts that are highly efficient and have numerous advantages over non-biological catalysts. They are non-toxic and biodegradable; work best at moderate temperatures and in mild conditions, and have fewer side reactions than traditional methods because they are highly specific. Production methods that use enzymes are generally not only cleaner and safer compared with other methods, but more economic in energy and resource consumption.

Many more of these biotechnological solutions for pollution have been developed. But biotechnology still can play an important role in further cleaning up the world and helping it stay clean.


Date: 2016-03-03; view: 1045

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