Could the same accident at Chernobyl happen in a CANDU 3 reactor?

Answer 1

No...

Answer 2

Actually a similar sort of accident could happen in the CANDU reactor. In a CANDU two types of water are used heavy water (which uses D2O) and regular light water. The heavy water is the moderator and is what slows down the neutrons. The light water is the coolant. The light water also acts as a light poison absorbing some neutrons and slowing the reaction.

The problem is that if the temperature starts to increase the light water will boil but the heavy, which is contained around the core, will not. And the over power of the reactor will actually increase a little. This is because the amount of light water a neutron will encounter is decreased a little. As the power increases the temperature will increase, increasing the power even more, and so on so forth. This is very similar to what happened in Chernobyl except instead of having heavy water Chernobyl used graphite.

Normal reactors do not have this problem. This is because they use light water as both a coolant and moderator. So if the water boils there is less material slowing down the neutrons and the power will decrease cooling the reactor.

Answer 3

Not likely since in the event of a LOCA, the reaction will die down by moderator boling off. And CANDU doesn't have the graphite like Chernobyl to catch fire and burn.