Getting Energy from Chernobyl

[TheGatesofLogic]

if there is one thing that surprises me about chernobyl more than anything else, it is that it was constructed in the first place. The way it was constructed meant that it was built with two extremely stupid features, one: it had a positive temperature coefficient, which means that as the reactor got hotter it produced more thermal energy, which was very bad, and two: it was built without almost any shielding at all. Very poor design choices, even considering what they knew back then. The designers should have known far better.

[pizzaoverhead]

graphite moderators

Very poor design choices

Another thing worth pointing out: Graphite isn't used as a moderator any more, and Chernobyl gives a great example why: At reactor temperatures, it burns well. After the steam explosion wrecked the reactor, the lack of water allowed the graphite to catch fire, lifting particles from the core into the air with the smoke, and spreading it into the surrounding landscape. This was the cause of the "nuclear fallout" from Chernobyl.

EDIT: On further reading, there is evidence to suggest that graphite did not play a major role in the Chernobyl reactor fire. It has also been discovered that the graphite did not burn during the 1957 Windscale reactor fire in the UK.

Edited September 12, 2014 by pizzaoverhead

[lajoswinkler]

Graphite does not burn in air unless it is close or at temperature of sublimation. It does slowly oxidize, though, but that's not burning. It can't sustain the fire because the released energy is not sufficiently large to keep the temperature at the needed levels (as for example wood or wax).

At first, there had to be some burning graphite because the temperatures were insane, but they quickly subsided and were replaced by ordinary fires. The materials were contaminated with fission products, so highly radioactive fumes and aerosols were seeping out all around Europe, including my home.

[TheGatesofLogic]

Well, the Chernobyl reactor didn't actually release much aerosol radioactive material... Any study which claims it did is fabricating or misrepresenting data. In fact, there should have been no noticeable difference in the local radioactivity anywhere outside a 10 mile radius from the reactor. Chernobyl only had a noticeable effect on the health of about 3000 individuals, so unless you lived near to the reactor you didn't actually encounter any contamination at any marginal level.

[peadar1987]

Well, the Chernobyl reactor didn't actually release much aerosol radioactive material... Any study which claims it did is fabricating or misrepresenting data. In fact, there should have been no noticeable difference in the local radioactivity anywhere outside a 10 mile radius from the reactor. Chernobyl only had a noticeable effect on the health of about 3000 individuals, so unless you lived near to the reactor you didn't actually encounter any contamination at any marginal level.

It depends what you mean by "noticeable". The first anyone in the West knew about it as when the increased radiation levels set off alarms at a nuclear plant in Sweden, over 1000km away. The levels weren't harmful, but they were definitely elevated.

[magnemoe]

It depends what you mean by "noticeable". The first anyone in the West knew about it as when the increased radiation levels set off alarms at a nuclear plant in Sweden, over 1000km away. The levels weren't harmful, but they were definitely elevated.

yes, remember i saw the log from an radioactivity logger in Norway. No health effects except some meat from animals who ate plants who accumulates lot of radioactivity become more radioactive than legal.

Granted the limits are set very low as its no reason to set them higher.

As I understand in the area close to Chernobyl you got lots of radioactive dust who hanged around for years in places.

[lajoswinkler]

Well, the Chernobyl reactor didn't actually release much aerosol radioactive material... Any study which claims it did is fabricating or misrepresenting data. In fact, there should have been no noticeable difference in the local radioactivity anywhere outside a 10 mile radius from the reactor. Chernobyl only had a noticeable effect on the health of about 3000 individuals, so unless you lived near to the reactor you didn't actually encounter any contamination at any marginal level.

You are joking, right?

Chernobyl released 5200 petabecquerels of radioactive material and there was a HUGE dump of it on Belarus. No noticeable difference outside 10 mile radius? Where did you pick up that crappy "data"?

There were bans on milk throughout Europe because of Sr-90. It's true that only several thousand people had noticeable effects on their health, but there was a lot of contamination way outside country borders.

[TheGatesofLogic]

where did i get that crappy data? An uncle who led one of the response teams and worked at Oak-ridge national laboratory as the Non-destructive Assay Team Lead, but i also am very familiar with the data personally. To clarify my point before, when i said noticeable, i did not mean on a detection level basis, i meant on a physiological basis. The effects of the radiation outside of a 10 mile radius should have been miniscule physiologically. There certainly was a large amount of radioactive material released, however the percentage of which was aerosols was minor in comparison to what would ultimately be necessary to cause an effect on the body (for more regarding this look into hormesis and the ULLR laboratory). Also, the primary reason Belarus recieved such a comparatively high dose of contaminants was because the Soviets seeded rains in the area, forcing release of the aerosol particles, a move which arguable increased the rate of fallout so significantly that it should never have been done in the first place, as the concentrations would have been effectively lowered even if it had traveled to more populated regions.

[peadar1987]

The short-term effects outside a fairly short radius would have been minimal. No radiation poisoning or burns or whatever. The longer-term effects, primarily an increase in various cancers, but also things like foetal abnormalities, are less clear, but are generally thought (and estimated by the WHO) to be far more widespread.

The problem is we don't actually know what low levels of radiation do to people. We can't exactly do a controlled trial, because that would be horrifically unethical, so the effects of low doses are interpolated from data we have about much larger doses, (mainly Hiroshima and Nagasaki survivors). From that we estimate that a low dose will cause an increase in the likelihood of developing cancer, but we actually don't know whether or not this is true, and it's very hard to pick out any concrete impacts from the statistical noise.

[lajoswinkler]

where did i get that crappy data? An uncle who led one of the response teams and worked at Oak-ridge national laboratory as the Non-destructive Assay Team Lead, but i also am very familiar with the data personally. To clarify my point before, when i said noticeable, i did not mean on a detection level basis, i meant on a physiological basis. The effects of the radiation outside of a 10 mile radius should have been miniscule physiologically. There certainly was a large amount of radioactive material released, however the percentage of which was aerosols was minor in comparison to what would ultimately be necessary to cause an effect on the body (for more regarding this look into hormesis and the ULLR laboratory). Also, the primary reason Belarus recieved such a comparatively high dose of contaminants was because the Soviets seeded rains in the area, forcing release of the aerosol particles, a move which arguable increased the rate of fallout so significantly that it should never have been done in the first place, as the concentrations would have been effectively lowered even if it had traveled to more populated regions.

So your uncle said the contamination was minimal outside 10 mile radius? That's a blatant lie.

Here's one of the more known maps, this one dealing with Cs-137 contamination.

There are places in Austria where almost 200 kBq of Cs-137 ions fell onto a square metre. It even rained on me.

I'm acquainted with hormesis and physiology and all that. I understand, but saying there was negligible contamination outside 10 mile radius is... There are no words how wrong it is.

[lajoswinkler]

The short-term effects outside a fairly short radius would have been minimal. No radiation poisoning or burns or whatever. The longer-term effects, primarily an increase in various cancers, but also things like foetal abnormalities, are less clear, but are generally thought (and estimated by the WHO) to be far more widespread.

The problem is we don't actually know what low levels of radiation do to people. We can't exactly do a controlled trial, because that would be horrifically unethical, so the effects of low doses are interpolated from data we have about much larger doses, (mainly Hiroshima and Nagasaki survivors). From that we estimate that a low dose will cause an increase in the likelihood of developing cancer, but we actually don't know whether or not this is true, and it's very hard to pick out any concrete impacts from the statistical noise.

Actually, we know quite a lot except what's impossible to pull out because of the very nature of statistical noise.

"Developed" countries like USA used to poison people (no consent) with radionuclides, telling them it's something else, and then measure data.

[TheGatesofLogic]

First off, my uncle is just part of the source. I would rather not reveal my personal knowledge regarding of the matter since this is the internet, but I am quite familiar with the effects physiologically. But again, minimal physiological effects, and yes, that map is accurate, but what it doesn't do is describe the rate of decay and energies of the other products in comparison to their specific average distribution, since cesium is not very dangerous below ingested concentrations on the order of tens of ingested MBq per kilogram of body mass. In general the heavier aerosols, (typically shorter lasting, higher energy or longer lasting, higher energy) are dumped out of the atmosphere very quickly. The quantities of very high energy long lasting radioactive material that drifted outside the immediate area is very low, and the amount of short lasting low energy radioactive waste that drifted outside the immediate area was extremely high, thus the data looks more dangerous than it truly is, since short lived waste has very little time to interact with humans on a physiological level. (92.6% of the radioactive products by mass and 74% by energy of the chernobyl accident would be classified in the French Low Level Waste designation if it were reactor waste products, while almost all of the rest would be Intermiediate Level waste, leaving the truly dangerous stuff, the High Level and Very High Level stuff less than 1% of the total in either measurement basis)

Edit for clarification: Cs-137 is a bad indicator in this sense as well, since it is one of the Low-level waste products i referred to and as such it leads to the map being very misleading

Edited September 13, 2014 by TheGatesofLogic

[Kryten]

That's a map of Cs-137 alone, so none of what you just said is relevant to it.

[TheGatesofLogic]

The map is misleading BECAUSE it only includes Cs-137.