Can someone explain this to me - nuclear reactors

[WiseOwlKnits]

So they're pouring sea water in to cool the reactors. Doesn't this pollute the sea water? Or does all the water boil off into steam? :confused:

[Mejane]

Seawater is often used to cool reactors. That's why so many are located on the coastline. Others are located by rivers or lakes. This (very long) article explains the process, but the snippet below sort of says it all:

 

http://www.world-nuclear.org/info/cooling_power_plants_inf121.html

 

"In a nuclear plant, beyond some minor chlorination, the cooling water is not polluted by use - it is never in contact with the nuclear part of the plant but only cools the condenser in the turbine hall."

 

I'm not sure if the situation in Japan is more complicated because fuel rods have been exposed. I'd ask my husband (who is in the power industry), but he's away at a meeting right now.

Edited March 18, 2011 by Mejane

[Pretty in Pink]

I can't find the article now, but I think the situation in Japan is a bit different than usual in that once the rods are exposed, the materials inside can heat up to such a high temperature that they begin chemically reacting with the metal around the rods. I believe this has already happened in Japan; an article I was reading the other day said that one by-product of those chemical reactions would be a hydrogen-containing compound; that could have been the cause of the explosions, which were caused by hydrogen reacting with oxygen either in the air or the sea water being used to cool the rods.