z*n
发帖数: 2893 | 1 仔细读了一下usatoday的文章, 好象没有想象中的严重.
地震的时候反应堆已经自动关闭, 余热大约是6%设计容量. 本来如果一切正常会在几天
到几周完全冷却下来, 结果海啸破坏了备用电机,冷却设施失灵. 余热破坏了燃料棒的
表层金属, 燃料棒/金属和水蒸气反应生成氢气, 氢气聚集产生爆炸.
现在的问题是要释放出反应堆里面的气体,这样冷却水才能进入,这些气体带有放射物质
. 不是反应堆能不能控制得住的问题, 是如何尽量安全的释放这些放射气体的问题, 什
么核爆之类是扯蛋.
以后的情况应当是"今天晴天, 风向又好, 赶快向外排一些气体...". 最坏情况就是污
染周围环境. 当初切尔诺贝利是反应堆在空气中燃烧, 放射物质直接随烟飘散, 完全不
是一个量级的事故. 同样的排气问题三里岛事故中也遇到过, 现在是three Three Mile
Island事故. | t*****y
发帖数: 445 | 2 你这个是之前的情况了
现在外层保护壳已经炸毁
3号很可能已经发生meltdown了
不会核爆炸，但如果金属保护壳损坏，会发生严重的核泄漏
Mile
【在 z*n 的大作中提到】
: 仔细读了一下usatoday的文章, 好象没有想象中的严重.
: 地震的时候反应堆已经自动关闭, 余热大约是6%设计容量. 本来如果一切正常会在几天
: 到几周完全冷却下来, 结果海啸破坏了备用电机,冷却设施失灵. 余热破坏了燃料棒的
: 表层金属, 燃料棒/金属和水蒸气反应生成氢气, 氢气聚集产生爆炸.
: 现在的问题是要释放出反应堆里面的气体,这样冷却水才能进入,这些气体带有放射物质
: . 不是反应堆能不能控制得住的问题, 是如何尽量安全的释放这些放射气体的问题, 什
: 么核爆之类是扯蛋.
: 以后的情况应当是"今天晴天, 风向又好, 赶快向外排一些气体...". 最坏情况就是污
: 染周围环境. 当初切尔诺贝利是反应堆在空气中燃烧, 放射物质直接随烟飘散, 完全不
: 是一个量级的事故. 同样的排气问题三里岛事故中也遇到过, 现在是three Three Mile
| z*n
发帖数: 2893 | 3 http://www.usatoday.com/news/world/2011-03-15-1Aquake15_ST_N.ht
两小时前的文章.
安吧, 最坏情况就是把所有气体全排出来, 往反应堆里灌水...
【在 t*****y 的大作中提到】
: 你这个是之前的情况了
: 现在外层保护壳已经炸毁
: 3号很可能已经发生meltdown了
: 不会核爆炸，但如果金属保护壳损坏，会发生严重的核泄漏
:
: Mile
| W***i
发帖数: 9134 | | t*****s
发帖数: 2933 | 5 以下是日本官方发布的顺序，
一开始，没有任何辐射泄露，
然后，一号暴了，有轻微泄露，
三号也暴了，有辐射，一百多人受污染了，
二号，四号 也暴了，疏散范围由20里到30里。
现在，400里东京也开始准备核微粒了，要求大家不要被雨水淋到。
目前官方承认是4级。
。。。。。。。。。
接下来呢？到此为止了么？
Mile
【在 z*n 的大作中提到】
: 仔细读了一下usatoday的文章, 好象没有想象中的严重.
: 地震的时候反应堆已经自动关闭, 余热大约是6%设计容量. 本来如果一切正常会在几天
: 到几周完全冷却下来, 结果海啸破坏了备用电机,冷却设施失灵. 余热破坏了燃料棒的
: 表层金属, 燃料棒/金属和水蒸气反应生成氢气, 氢气聚集产生爆炸.
: 现在的问题是要释放出反应堆里面的气体,这样冷却水才能进入,这些气体带有放射物质
: . 不是反应堆能不能控制得住的问题, 是如何尽量安全的释放这些放射气体的问题, 什
: 么核爆之类是扯蛋.
: 以后的情况应当是"今天晴天, 风向又好, 赶快向外排一些气体...". 最坏情况就是污
: 染周围环境. 当初切尔诺贝利是反应堆在空气中燃烧, 放射物质直接随烟飘散, 完全不
: 是一个量级的事故. 同样的排气问题三里岛事故中也遇到过, 现在是three Three Mile
| m*****n
发帖数: 5611 | 6 跟美国一点关系没有 洗洗睡吧
【在 t*****s 的大作中提到】
: 以下是日本官方发布的顺序，
: 一开始，没有任何辐射泄露，
: 然后，一号暴了，有轻微泄露，
: 三号也暴了，有辐射，一百多人受污染了，
: 二号，四号 也暴了，疏散范围由20里到30里。
: 现在，400里东京也开始准备核微粒了，要求大家不要被雨水淋到。
: 目前官方承认是4级。
: 。。。。。。。。。
: 接下来呢？到此为止了么？
:
| t*****y
发帖数: 445 | 7 2号的保护壳已经损坏了。。。
We are on the brink. We are now facing the worst-case scenario,” said
Hiroaki Koide, a senior reactor engineering specialist at the Research
Reactor Institute of Kyoto University. “We can assume that the containment
vessel at Reactor No. 2 is already breached. If there is heavy melting
inside the reactor, large amounts of radiation will most definitely be
released.”
放气体灌水从一开始就在做了
【在 z*n 的大作中提到】
: http://www.usatoday.com/news/world/2011-03-15-1Aquake15_ST_N.ht
: 两小时前的文章.
: 安吧, 最坏情况就是把所有气体全排出来, 往反应堆里灌水...
| t*****s
发帖数: 2933 | 8 当年 Chernobyl 核辐射微粒票遍欧洲。。。
【在 m*****n 的大作中提到】
: 跟美国一点关系没有 洗洗睡吧
| z*n
发帖数: 2893 | 9 爆的不是反应堆(reactor chamber), 是外面的建筑(reactor housing).
现在就是如何把放射性气体放出来的问题, 换中国政府估计是小菜一碟, 也就是在日本
全世界都看着.
科普一下发生了什么事情, 自己去读文章.
The cooling challenge
On Friday, when the magnitude-9.0 earthquake rocked Japan, all of the
reactors now in trouble automatically shut down. All are boiling water
models. Normally, they generate steam to make electricity, which then cools
and returns to the reactor chamber as water, ready to be boiled once more.
Control rods that turn off the atomic reaction between the fuel rods
automatically slid into place as soon as the quake started, sensed by motion
detectors in the floor of the reactor facility.
Despite the shutdown, the rods didn't cool off immediately. Leftover
radioactive heat remained inside them, perhaps 6% of its normal operating
energy. In a normal shutdown, cooling systems and pumps would control those
temperatures, dissipating them until the radioactive materials inside the
rod finished cooking off most of their energy in the coming days to weeks.
Instead, the tsunami disrupted power for the pumps and cooling systems,
leading the rods to heat up, boiling off the water that normally cools them.
On Saturday, the Tokyo Electric Power Co., which owns all three power
plants, alerted government officials to overheating in two reactors,
triggering emergency declarations.
"The problem then, is removing that (radioactive) decay heat," says nuclear
engineer John Gilligan of North Carolina State University in Raleigh.
Without cooling, Tokyo Electric Power Co. officials face a cascade of
problems:
•With cooling knocked out, the temperature in the rods rises, boiling
off more water, exposing the tips of the rods to steam and air.
•Once exposed to steam and air, the rods begin heating, leading to
blistering of the metal that covers them, letting radioactive elements
escape.
•The blistering also creates a chemical reaction between the steam and
metal, generating hydrogen gas that builds unsafe pressure in the reactor.
While generators were rushed to the power plants to restart power to the
cooling system over the weekend, engineers needed to vent radioactive gas
from the reactors to relieve this pressure. Desperate to cool the reactors,
they turned to piping seawater into two reactors at the Dai-ichi plant. "
That's an extraordinary thing to do," Alvarez says, because it means the
reactors, billion-dollar machines in today's market, will be contaminated
and never used again. Alvarez and others point to still more problems at the
reactors:
•Plutonium fuel inside one reactor, different from the uranium used in
the other reactors, may take longer to cool down than others, raising its
risks. Barrett calls that a very small concern.
•Venting the hydrogen inside the reactors led to explosions that have
injured 15 workers at the plants, and blew the roof off the outermost
containment building housing two of the reactors.
•Used-up fuel rods are on-site, kept in water pools above the reactors
. Leaks from those pools could lead to the release of radioactive elements
in the old, used-up fuel rods.
If steps to cool the reactor proceed without further mishaps, the reactors
should cool in the next few weeks, Gilligan says. Engineers will likely
continue having to vent small amounts of radioactive gas from the reactors
for months however, to keep the pressure off, even under the best of
scenarios.
"That's how it was at Three Mile Island," Barrett says. "The weather report
would say, 'Today will be sunny, and they will be venting gases today from
the plant.' "
containment
【在 t*****y 的大作中提到】
: 2号的保护壳已经损坏了。。。
: We are on the brink. We are now facing the worst-case scenario,” said
: Hiroaki Koide, a senior reactor engineering specialist at the Research
: Reactor Institute of Kyoto University. “We can assume that the containment
: vessel at Reactor No. 2 is already breached. If there is heavy melting
: inside the reactor, large amounts of radiation will most definitely be
: released.”
: 放气体灌水从一开始就在做了
| t*****y
发帖数: 445 | 10 现在说的就是reactor chamber有可能破损，而2号可能已经破损
大家都知道外面建筑爆炸了，现在担心的就是内层的再损坏
要是简单放气体灌水就能解决，自卫队和其他工作人员也就不撤退，早解决了
cools
【在 z*n 的大作中提到】
: 爆的不是反应堆(reactor chamber), 是外面的建筑(reactor housing).
: 现在就是如何把放射性气体放出来的问题, 换中国政府估计是小菜一碟, 也就是在日本
: 全世界都看着.
: 科普一下发生了什么事情, 自己去读文章.
: The cooling challenge
: On Friday, when the magnitude-9.0 earthquake rocked Japan, all of the
: reactors now in trouble automatically shut down. All are boiling water
: models. Normally, they generate steam to make electricity, which then cools
: and returns to the reactor chamber as water, ready to be boiled once more.
: Control rods that turn off the atomic reaction between the fuel rods
| s*y
发帖数: 18644 | 11 最新的消息是，这个气体可能会要排很久，几周到1年都可能，好像没有其他的办法降
温，就是灌水，排气。。。。
【在 z*n 的大作中提到】
: http://www.usatoday.com/news/world/2011-03-15-1Aquake15_ST_N.ht
: 两小时前的文章.
: 安吧, 最坏情况就是把所有气体全排出来, 往反应堆里灌水...
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