: 
: 
: I really don't know where to post this question so I figured that
: this board would be most appropriate.
: I was wondering about those massive concrete cylinders that
: are ever present at nuclear poer sites. They look like cylinders
: that have been pinched in the middle. Does anybody know what the
: actual purpose of those things are?. I hear that they're called
: 'Cooling Towers' but what the heck do they cool?
: I hope someone can help 
:-----------------------
During the nuclear fission reaction the uranium fuel can get hot enough
to melt. When this happens the liquid uranium is pumped to the cooling
tower where it is sprayed into the air. Contact with the cool outside air
will condense the mist and it will fall back to the cooling tower floor.
There it is collected by a cleaning crew using shop vacs and is then
reformed into pellets for reactor use the next day.

Cooling towers are a lot taller than they really need to be. Power companies
are forced to make them that tall by some enviromental law that requires the
raw uranium emisions to be held to under 1%. This law is now under attack
by lawyers arguing that the 1% should be measured at the edge of the property
rather than the edge of the cooling tower. Eliminating this law will save
power companies thousands of dollars in concrete costs for new nukes.