So, now that they're pumping in seawater in to these reactors, what happens to the

seawater after it's been run over the radioactive rods?...pumped back out to sea?...stored?...just converted into radioactive steam?

About as accurate as anything the Japanese government says.

Usually.

They're pumping in seawater because the usual systems are no longer working.

The reactors in question are BWRs and have no heat exchangers/steam generators.

where the coolant (sea water) enters and leaves. Notice how the coolant doesn't come into contact with the reactor? That is thanks to a heat changer. Rather than asking me if I know the difference, why not ask the folks at Wiki why their diagram didn't label all the parts? :shrug:

Not the cooling loop used to cool and condense the steam that went through the turbine.

Yes, BWRs do have a heat exchanger in their design, but that's not what they're talking about here. That water in the heat exchanger is way far down the line from the actual reactor.

We are at such a bad point, they are having to pump water into the reactor directly. That's why this is so bad.

And God they are lying and those reactor containment systems didn't probably make it through the explosion safely, without even the slightest crack, right?

I'm so sick and fucking tired of this shit.

and a BWR like the one at Fukushima.

First the PWR:


At points 6 and 7, you will notice there is NO FUCKING HEAT EXCHANGER!

Down the line at point 12 there is. This is usually what cools and condenses the water after it's gone through a turbine in a BWR (boiling water reactor). This is not to mistaken as a full separation between the reactor and external water going into the rest of the plant, however. The steam comes directly from the reactor in a BWR.

However, in a PWR, or pressurized water reactor. No water in the core itself ever boils under normal circumstances. And there is a heat exchanger separating water that becomes steam and goes through the turbines from the water circulating in the core.

Here is a simple diagram of that:


In this diagram the heat exchanger is a "steam generator". Now you will also notice that down the line AFTER the turbines there is another heat exchanger. This one is the like the ONLY heat exchanger in a boiling water reactor. It serves the same purpose, to cause the steam to condense back down into water, by transferring heat to water that flows freely in and out of the plant.


NOW back to the BWR:


At point 1, there is coolant in there, and that in these reactors at Fukushima is low. So low that fuel rods are no longer being actively cooled. This is a problem, because although there are control rods that sort of shut down the reactions causing heat to be made, they do not themselves radiate heat away from this pressure vessel. So they can be in there, and unless there is cooling still going on during shut down, you will perhaps see the fuel rods melt (called a meltdown.)

This believed to be what's happening now, unfortunately. And this may very well breach the containment of the reactor if cannot be stopped and this means that radioactivity in large amounts could be released into the surrounding environment. If you've ever heard of the China Syndrome, that's what I'm talking about.

is even if it was in front of you (which it is in this case). Stop spreading hysterical misinformation.

However, there is not one between the reactor coolant the turbines in BWR.

That's not misinformation, that's the truth.

:facepalm:

Really?

Nuclear power plants work.



Really.

I just want your incredible ignorance and arrogance on display for all.

Feel free to prove me wrong, educate all of us.

with seawater are in the reactor vessel.



Now, I'd just LOVE to hear where you think they are.

Care to elaborate?

This sure makes it sound like the sea water is going into the reactor itself.

When they are talking about doing this, it goes right in there.

And that also means they're not planning on using that shit ever again, so it must be too far gone!

They need to add water in two places.

1) Primary coolant loop. Water has droped too low due to excess boiling. Adding water here would be a one way trip. The boron is a safety measure that would prevent criticality even if the fuel rods are melted (thus making control rods ineffective). This water stays in the reactor and replaces the water that was their under routine operation (it boiled off when reactor overheated).

2) They will use seawater to cool the primary loop. This water will be returned to the ocean and be a continual process. This water will not be exposed to the core.

Kicking the can down the road.

That unfortunately appears to be leaking out of the reactors as fast as they're pumping it in. Given the plant's location, the bulk of this almmost certainly ends up in the sea.

It's the kind of thing that would be a really big deal in other circumstances (I'm sure it's quite a bit more substantial than the tritiated water leaking out of a couple US reactors), but in context of the greater danger, it's not a major issue.

Unfortunately, it sounds like in all 3 reactors, it HAS been compromised, so presumably you're having all sorts of shit mixed in with the steam and waste.

It is hardly what anyone would call an ideal situation.

but the water doesn't appear to be spending much time in or around the core. It's leaking out (reportedly) as fast as they pump it in.

The activity levels in the core should be declining pretty rapidly as well... so that should make a difference.

and a short half life. Also water is "resistance" to neutron capture and thus only a tiny fraction becomes irradiated (usually less than 1%).

Which would contaminate it with uranium and all kids of ugly fission byproducts.

the primary coolant loop is a closed system. Contaminants would remains in the primary cooling loops. Not a good situation but harldy like dumping spent fuel into the ocean.

Are the pressure vessels losing coolant only because it's boiling off and they're having to release pressure, or is there a leak in the pressure vessel?

Can they even know at the current time if the valves controlling the flow of coolant are working properly?

Are they visually inspecting this? Wouldn't any cameras have been damaged in the hydrogen-oxygen explosions that were obviously strong enough to disintegrate the containment buildings?

Just asking.

That shouldn't be happening if they have containment, right?

:argh:

http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=102x4771621

into contact with unusable.

that's if the rods don't melt

they had hydrogen explosions. Neither plant will ever run again.

They made the decision to use seawater knowing that is essence they are writing the plant off forever.

not all radiation is equal.

There is a difference between radiation (energy) and radioactive material (material that now emits energy). Also not all the water goes into the core.


Water is being added to the core. That water is converted into steam and it flows into a condensor where more sea water (second loop) cools it back into water.

Only the water directly added to the core is exposed to radiation. Oxygen is extremely resistant to radiation and will not become radioactive. Some of the hydrogen in the water can be converted into an unstable isotope, tritium. In a normal reactor less than 1% of the water turns into tritium. Most of the water never becomes radioactive but some of it will. A small portion of steam is periodically vented to reduce pressure so some tritinated steam will escape

Most of the water is being used in the second loop and thus is not radioactive. Some water will need to be added to the core to replace water lost and that will become radioactive. Lastly tritium has a short half life (12 years) and will decay back into inert "normal" water. Also if you absorb tritium it leaves the body quickly (about 10 days) minimizing damage.

:eyes:

water goes.

They covered this on the news. Most of the seawater is being used to try and cool down the steam before the pressure gets too high and forces them to release contaminated steam. The water used in that process does not come in contact with contaminants from the fuel rods.

Also, I just saw where they may need to continue to release contaminated steam for months.

the ocean is a toilet don't cha know. :banghead: