User:Milton Beychok/Sandbox: Difference between revisions

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As most [[ore]]s in the Earth's [[Crust (geology)|crust]], coal also contains low levels of [[uranium]], [[thorium]], and other naturally-occurring [[radioactive isotopes]] whose release into the environment leads to radioactive contamination. While these substances are present as very small trace impurities, enough coal is burned that significant amounts of these substances are released. A 1,000 MW coal-burning power plant could release as much as 5.2 tons/year of uranium (containing {{convert|74|lb|kg}} of [[uranium-235]]) and 12.8 tons/year of thorium. The radioactive emission from this coal power plant is 100 times greater than a comparable nuclear power plant with the same electrical output; including processing output, the coal power plant's radiation output is over 3 times greater.<ref>[http://www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html Coal Combustion: Nuclear Resource or Danger?] by Alex Gabbard, [[ORNL]] Review, Summer/Fall 1993, Vol. 26, Nos. 3 and 4.</ref>
===Radioactive trace elements===
 
As most [[ore]]s in the Earth's [[Crust (geology)|crust]], coal also contains trace levels of [[uranium]], [[thorium]], and other naturally-occurring [[radioactive]] elements. 
 
A report developed at the [[Oak Ridge National Laboratory]] (ORNL) estimated that the amount of coal burned each year in a typical 1000 MW coal-fired power plant contained about 5.2 tonnes of uranium and about 12.8 tonnes of thorium.<ref name=Gabbard>[http://www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html Coal Combustion: Nuclear Resource or Danger?] (by Alex Gabbard, [[ORNL]] Review, Summer/Fall 1993, Vol. 26, Nos. 3 and 4.</ref> The basis of ORNL estimate was that the annual coal consumption was 4 Mt and that the coal contained 1.3 ppm of uranium and 3.2 ppm of thorium.
 
Assuming that all of the uranium and thorium would be emitted into the fly ash and that the electrostatic precipitators would capture and remove 99% of the fly ash, the emissions of radioactive trace elements to the atmosphere from a 1000 MW coal-fired power plant would be 52 kg/yr of uranium and 128 kg/yr of thorium.
 
The average annual radiation received by a person from all sources (cosmic radiation, ground radiation, food intake, water intake, air intake, air travel, brick or stone or concrete home construction  and miscellaneous other sources) is 360 millirem.<ref name=DOERadiationBasics>[http://www.etec.energy.gov/EIS/Documents/Radiation_Basics_2008-07-22.pdf Radiation Basics] (U.S. DOE website page)</ref> The annual radiation received by persons living within 80 km of a coal-fired power plant is 0.03 millirem.<ref name=DOERadiationBasics/><ref>[http://www.epa.gov/radiation/understand/calculate.html Calculate Your Radiation Dose] U.S. EPA website page</ref>
 
 
 
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Revision as of 19:21, 23 December 2008

Radioactive trace elements

As most ores in the Earth's crust, coal also contains trace levels of uranium, thorium, and other naturally-occurring radioactive elements.

A report developed at the Oak Ridge National Laboratory (ORNL) estimated that the amount of coal burned each year in a typical 1000 MW coal-fired power plant contained about 5.2 tonnes of uranium and about 12.8 tonnes of thorium.[1] The basis of ORNL estimate was that the annual coal consumption was 4 Mt and that the coal contained 1.3 ppm of uranium and 3.2 ppm of thorium.

Assuming that all of the uranium and thorium would be emitted into the fly ash and that the electrostatic precipitators would capture and remove 99% of the fly ash, the emissions of radioactive trace elements to the atmosphere from a 1000 MW coal-fired power plant would be 52 kg/yr of uranium and 128 kg/yr of thorium.

The average annual radiation received by a person from all sources (cosmic radiation, ground radiation, food intake, water intake, air intake, air travel, brick or stone or concrete home construction and miscellaneous other sources) is 360 millirem.[2] The annual radiation received by persons living within 80 km of a coal-fired power plant is 0.03 millirem.[2][3]


  1. Coal Combustion: Nuclear Resource or Danger? (by Alex Gabbard, ORNL Review, Summer/Fall 1993, Vol. 26, Nos. 3 and 4.
  2. 2.0 2.1 Radiation Basics (U.S. DOE website page)
  3. Calculate Your Radiation Dose U.S. EPA website page