what is the difference between depleted and enriched uranium??

Question

thanks for answers!

Answer 1

Natural uranium metal contains about 0.71% U-235, 99.28% U-238, and about 0.0054% U-234. In order to produce enriched uranium, the process of isotope separation removes a substantial portion of the U-235 for use in nuclear power, weapons, or other uses. The remainder, depleted uranium, contains only 0.2% to 0.4% U-235. Because natural uranium begins with such a low percentage of U-235, the enrichment process produces large quantities of depleted uranium. For example, producing 1 kg of 5% enriched uranium requires 11.8 kg of natural uranium, and leaves about 10.8 kg of depleted uranium with only 0.3% U-235 remaining.

enriched uranium for nuclear plants is about 5% U-235, weapons grade enriched uranium is > 90% U-235.

Answer 2

first, uranium exists as several different isotopes.

Uranium 238 is the most abundant with 92 protons, 92 electrons, and 146 neutrons.

Uranium 235 is the next most abundant with 92 protons, 92 electrons, and 143 neutrons.

Uranium 235 is the form used in nuclear power plants and in atomic weapons because it can undergo "induced" fission. ie one atom fizzes and releases alpha particles, etc, a second atom will readily capture that alpha particle and will then undergo fission of it's own. U238 does not readily absorb alpha particles.

naturally occurring uranium, which can be found essentially everywhere, contains approximately 99.3% U238 and 0.7% U235. to undergo induced fission in a useful enough scale for a reactor, the concentration of U235 must be approximately 5% (90% U235 is required for weapons).

During the enrichment process, usually performed in gas phase made by reacting uranium with HF to make uranium hexaflouride, some U235 is removed from the 0.7% stream and placed in another stream. a stream more concentrated with U235. The result is the concentration of U235 in the original stream drops from 0.7% to approximately 0.2%. This stream is called the "depleted uranium" stream because it is depleted in U235. the other stream is called the "enriched" stream because the concentration of U235 is increased.

***** update ******

spent fuel rods are NOT depleted uranium. Spent fuel rods may be reprocessed via the uranium enrichment process, but spent rods are NOT depleted uranium.

Depleted uranium is relatively safe. see here
http://66.218.69.11/search/cache?ei=UTF-8&p=depleted+uranium+safety&fr=yfp-t-501&u=www.gao.gov/new.items/ns00070.pdf&w=depleted+uranium+safety&d=O_kp2OrnO8TF&icp=1&.intl=us

spend nuclear fuel rods are not safe at all. They must be stored precisely. They are generally not reprocessed due to the difficulty of reprocessing.

Answer 3

Natural uranium contains 0.7% of U235 and the balance U238. Uranium containing more than 0.7% of U235 is enriched. Many nuclear reactor fuels and nuclear weapons contain very high percentages of U235. Percentage of U235 can be increased by enrichment processes such as gaseous diffusion, centrigufe process, laser process etc. The uranium left behind is obviously depleted in U235.

Spent fuel also contains less U235 since some of it was used in reactor to produce fission. Thus depleted Uranium can come from two sources.

Answer 4

Enriched uranium is a sample of uranium in which the percent composition of uranium-235 has been increased through the process of isotope separation. Natural uranium is 99.284% 238U isotope, with 235U only constituting about 0.72 % of its weight. However, 235U is the only isotope existing in nature (in any appreciable amount) that is fissionable by thermal neutrons.
printable version

Depleted Uranium
Uranium (U) is used primarily as fuel material in nuclear power plants. However, most reactors require uranium in which the 235U content is enriched from its naturally occurring concentration. The uranium remaining after removal of the enriched fraction is referred to as depleted uranium (DU). DU is weakly radioactive and a radiation dose from it would be about 60% of that from purified natural uranium with the same mass. It is used in armour penetrating military ordinance because of its high density, and also in the manufacture of defensive armour plate.

Answer 5

Most uranium is U238, U235 is more fissionable. Enriched has more U235 isotope.
Depleted generally refers to spent fuel rods that have been used in nuclear generating plants. It has less U235, but is still radioactive.

Answer 6

enriched U has high quantity of U235 whereas the quantity avail. is less due to decay in the other one