Control and Prevention

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The best way to control pollutants is to prevent them from forming in the first place. The obvious choice is to reduce fossil fuel consumption and switch to cleaner sources of energy. Short of that, cleaning the fuel and subsequently modifying combustion processes is probably our next best option. As a last resort, we may opt to remove gaseous and particulate pollutants from the exhaust before they are released into the atmosphere. Fortunately, technologies exist that can help reduce environmental impact at every stage in the process. New technologies have made many alternative and renewable sources of energy cheaper and, in some instances, competitive with fossil fuels. Several new processes have been developed that show the promise of more efficient combustion and reduced air pollution. Cogeneration and combined cycle combustion turbines have helped to improve efficiency and reduce pollution considerably.

Coal combustion has become cleaner as well. For example, in fluidized bed combustion, coal is pulverized and suspended on a bed of air, thus reducing combustion temperature which reduces nitric oxide emission.

These technologies can reduce particulate and sulfur emissions to a great degree but still produce substantial amounts of gaseous emissions which must be removed before they are released into the atmosphere (end-of-the-pipe control technologies). Depending on the nature and size of the particulates, they can be removed by cyclones, bag houses, filters, scrubbers, or electrostatic precipitators. Gaseous pollutants can be removed by physical and chemical adsorption. Sulfur dioxide emission can be controlled by fuel desulphurization and limestone scrubbing. Nitric oxides and oxides of carbon are best removed by catalytic converters and other flue gas treatment techniques (Cooper, 1994). Automobiles are another source of emission. Vehicular emission is controlled by catalytic converters, where small pellets of palladium and platinum transform carbon monoxide and nitric oxides into carbon dioxide and nitrogen. Automotive emission will be discussed in greater detail in transportation.


(1) Cooper, C. D., Alley, F. C., “Air Pollution Control-A Design approach,” Waveland Press, Inc., 1994.

(2) Toossi Reza, "Energy and the Environment:Sources, technologies, and impacts", Verve Publishers, 2005

Further Reading

Gore, A., An Inconvenient Truth, Penguin Books, 2007.

Roleff, T., Pollution: Opposing viewpoints, Greenhaven Press, 2000.

Walsh, P. J., Dudney, C. S., Copenhave, E. D., Indoor Air Quality, CRC Press, 1984.

Environmental Science and Technology, published by the American Chemical Society.

External Links

Environmental Protection Agency (

Occupational Safety and Health Administration (OSHA) (

Intergovernmental Panel on Climate Control (IPCC), (

United Nations Environment Programme (

World Health Organization (WHO) (