In No 4, cool down system in spent fuel pool stopped. On 5th of May, 11:00 the temperature was 34 Celsius degree. It rises 7.2 Celsius degrees a day. If it boils, the spent fuel rods are in danger.
Now it's 2 PM, 6th of May..the temperature must be 42.1.
So let's see. If the temperature rises at 7.2°C per day, it will take roughly 8-9 days to reach 100°C.
ReplyDeleteThen, given that it takes 1 calorie to raise 1 gram of water 1°C, but 540 calories to boil 1 gram of water at 100°C, it would take 4000 to 5000 days to boil off the water in the spent-fuel pool.
I think there is plenty of time to do something.
huh. I suppose we could say it would be a problem if the rods are only exposed a few inches. So the entire tank volume need not be boiled off for there to be a
ReplyDelete"Houston we have a problem" moment. But at a minimum a few days before the water reaches boiling temperatures. I wonder what volume that holding pool has?
ohhh wait, the volume issue is already calculated for us if we know how fast the temperature rises in the pool each day. Or at least, we know that the pool mass and energy emitted gives rise to a temperature increase of 7.2 degrees C over a 24hr period. which means we have a known Energy input to mass ratio.
ReplyDeleteThe known constant is 2.06 Joules energy needed to raise 1 gram of water 1 degree Celsius.
Q = m * T(delta) * Cp
Where Q is how much energy is needed to raise m mass of water by T degrees and Cp is the constant mentioned above.
So
Q/M = T * Cp
And if the (delta) T is 7.2 Degrees C per 24hours, then our Energy to Mass ratio for the pools + rods is:
Q/M = 2.06*7.2C
That means our Energy to Mass per 7.2C increase per day ratio is 14.832, for whatever value of mass of water we have and whatever rate of introduction of energy.
4.184 joules (one calorie).
ReplyDeletescience fail. I copied and pasted from a site with out checking. hehehee
ReplyDeleteI know so much of this crap cold it's not funny.
ReplyDeleteThe cooling system is recovered in the evening on the same day. It often gets out of control. Three times in the past. For those who are earnestly waiting for the last day, it is a ray of hope.
ReplyDeleteSo you're telling me that it requires several days before it gets hot enough to be a problem and would not be a safety hazard for weeks, but you're concerned about downtimes of hours.
ReplyDeleteWhy are you concerned about this? Are the news reports covering every change in breathless, panicked tones? Are you picking up on the panic?
The solution is to ignore the news reports. There are more important things they SHOULD be covering (like the corruption in the hauling contract), but instead they're giving you junk. Punish them for it; take away your attention, and complain to their advertisers.
Workers have to get away from the site if coolant system stopped, although fuel rods are safe. If workers can't work there, no one can maintain the site. All we can do will be just wait for critical prompt. So catastrophe is over there.
ReplyDeleteSo you're saying that work is delayed a few hours while the coolant system is fixed. Does this harm anything?
ReplyDeleteIf the regulations requiring workers to be removed if the coolant system stops are causing more harm than they are preventing, the solution is to change the regulations. Perhaps nothing needs to be done until the coolant system has been off for 24 hours? That would make life easier for everyone except the reporters hanging breathlessly on every bit of news from Fukushima Dai'ichi, and the advertisers buying time on their shows.