Heavy water(PHWR)--Pressurised heavy water reactor
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Tritium is formed by the capture of neutrons by deuterium (heavy hydrogen) which is in the heavy water in the moderator and coolant.
moderator, coolant
Different types of nuclear plants: Pressurised Water Reactor (PWR); Boiling Water Reactor (BWR); Heavy Water Moderated Reactor (CANDU); Advanced Gascooled Reactor (AGR); Fast Breeder Reactor (FBR); Pebble Bed Gascooled Reactor; Water Cooled Graphite Reactor (RBMK). There are other ideas that only exist on paper.
This is done in order to limit corrosion of the internal reactor components
CANDU, a reactor type designed in Canada which uses heavy water as the primary coolant.
Most often, light water (H2O) is used as a moderator in a nuclear reactor. Sometimes, heavy water (D2O), or graphite is used.
This is the function of the moderator, which may be heavy water, light water, or graphite
Zerlina.
Heavy water
The heavy water in a heavy water reactor is water where many of the regular hydrogen atoms (one proton and one electron) are replaced by heavy hydrogen (or deuterium) which has one proton, one electron, and one neutron. The addition of the neutron in the hydrogen atoms increases the mass (weight) of the water molecules and changes its chemical and physical properties making it useful in a heavy water reactor.Normal water is H2O or two hydrogen atoms and one oxygen atom. There is an isotope of hydrogen named deuterium. Deuterium is heavier than hydrogen but it's still hydrogen, so if one or more of the hydrogen atoms is replaced with deuterium it creates heavy water. So the water in a heavy water reactor is just water with deuterium atoms rather than ordinary hydrogen atoms. This is probably confusing but it is water and you could drink it without harm. But, don't drink a lot because the body is used to the lighter water.