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Higher operating temperatures require more cooling water than a coal-fired plant of the same electricity generation capacity. Nuclear plants generate electricity in a steam cycle similar to the system in coal plants, except that nuclear fission is the source of heat for the boiler. operates 104 nuclear fission plants with a combined rated capacity of 101 GW. In December 2008, 438 nuclear fission plants with a combined rated capacity of 372 GW were operating in 31 countries ( IAEA, 2009). Uranium conversion, enrichment, and fuel fabrication require toxic chemicals, including fluorine gas, which is lethal on contact to animals, damages vegetation, and forms toxic by-products. Mining and milling of uranium ore creates most of the same environmental problems described for deep coal mines and coal processing. Fuel fabrication then produces 30 Mt of uranium dioxide (UO 2) pellets for use in the nuclear reactor core. The original 150,000 Mt of ore for a standard 1 GW nuclear fission plant has thus yielded 31 Mt UF 6 enriched in uranium-235. Continuation of the process produces material enriched to 97–99% uranium for nuclear warheads. Nuclear fission for electricity generation requires enrichment to 2–3% uranium-235. Processors use one of three methods – gaseous diffusion, gas centrifuge separation, or liquid thermal diffusion – to divide UF 6 into separate fractions, one of which is enriched in a higher concentration of uranium-235 than found in nature. Fluorination of the yellowcake produces 188 Mt of uranium hexafluoride (UF 6). Milling, roasting, and acid leaching of the ore produces 150 Mt uranium oxide (U 3O 8) in a granular form called yellowcake as well as substantial amounts of ore tailings and chemical effluents. A standard 1 GW nuclear fission plant requires 150,000 Mt uranium-containing ore to fabricate enough fuel for 1 year. The isotope uranium-238 accounts for over 99% of the uranium in nature, but nuclear fission fuel requires the uranium-235 isotope. Uranium rests in geologic strata in the minerals uraninite and pitchblende. Nuclear fission plants require highly processed uranium fuel. The similarity of the atomic structure of strontium to calcium increases the uptake of strontium by animals and its incorporation into bones. While the half-life of strontium-90 is 29 years and the half-life of cesium-137 is 30 years, plutonium-239 decays with a half-life of 25,000 years, and a quantity of iodine-129 will decay to half of its mass only after 17 million years. When radiation passes through living tissue, the particles or photons impart their energy to atoms and molecules in the tissue, disrupting molecular and atomic structures.įission products emit radiation until they reach a stable atomic state. Radiation consists of kinetic energy of small molecules and atomic particles and electromagnetic energy of photons traveling at certain frequencies. A fission reaction produces energy in the form of light, heat, motion of the fission products, and radiation. Uranium and plutonium are the elements that provide the most effective yield from fission. Nuclear fission is the splitting of high-molecular-weight elements to release energy held by protons and neutrons in the nucleus of the atom. This “missing” mass has been converted into energy according to Einstein’s equation: Fission can occur when a nucleus of a heavy atom captures a neutron or it can happen spontaneously.Patrick Gonzalez, in Encyclopedia of Biodiversity (Second Edition), 2013 Nuclear Fission The sum of the masses of these fragments is less than the original mass. These fragments or fission products are about equal to half the original mass. When a nucleus fission, it splits into several smaller fragments. The equation of the reaction has been given below. The missing mass is what is converted into nuclear energy in the above reaction.Īn example of nuclear fission is the splitting of Uranium – 235. The resulting fragments tend to have a combined mass which is less than the original. This decay can be natural or can actually be simulated in a lab by achieving necessary conditions. Nuclear Fission:When the nucleus of an atom splits into lighter nuclei through a nuclear reaction the process is termed as nuclear fission. Nuclear power plants produce energy using nuclear fission.

In nuclear fission, the division of atoms takes place to form smaller atoms by releasing energy.

In nuclear fusion, atoms combine together to form a larger atom. Nuclear Energy is discharged by nuclear reactions either by fission or fusion. Where an atom is a tiny particle that constitutes every matter in the universe. Nuclear Energy is the energy in the core of an atom.