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Integral Fast Reactor

by catseye747
Tags: integral, reactor
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sloughter
#145
Jun15-09, 02:40 PM
P: 19
The major problem with Inertial Confinement Fusion is that physicists think it is a physics problem. It is an engineering problem. Getting fusion is 1% of the job. 99% is the supporting engineering. I don't see anyone defending the farcical cartoon on Charlie Gibson showing an ICF reactor firing every second (Do you really think that it is possible to go from 100,000,000 degrees to -260 degrees in under one second?). Do you really think that you can isolate lasers from the explosive force of a 100 pound stick of dynamite going off a few feet away? Do you really think that one detonation means anything when you are going to have to get a detonation every second? Do you really think hitting a stationary target has any relevance to hitting a moving target? Hitting a static target is comparable to hitting a missile on a launch pad as opposed to hitting it in flight. Do you really think that Star Wars in a bottle is feasible?

This is just a partial list of all the engineering problems faced by ICF engineers.

Quote Quote by Captainjf View Post
I am in debate and i was instructed by my teacher to find negative evidence on the IFR reactor. is there anything wrong with the reactor that stands out alot?
Morbius
#146
Jun15-09, 02:56 PM
Sci Advisor
P: 1,160
Quote Quote by sloughter View Post
The major problem with Inertial Confinement Fusion is that physicists think it is a physics problem. It is an engineering problem. Getting fusion is 1% of the job. 99% is the supporting engineering. I don't see anyone defending the farcical cartoon on Charlie Gibson showing an ICF reactor firing every second (Do you really think that it is possible to go from 100,000,000 degrees to -260 degrees in under one second?). Do you really think that you can isolate lasers from the explosive force of a 100 pound stick of dynamite going off a few feet away? Do you really think that one detonation means anything when you are going to have to get a detonation every second? Do you really think hitting a stationary target has any relevance to hitting a moving target? Hitting a static target is comparable to hitting a missile on a launch pad as opposed to hitting it in flight. Do you really think that Star Wars in a bottle is feasible?

This is just a partial list of all the engineering problems faced by ICF engineers.
sloughter,

Funny you should mention "Stars Wars'. I remember when so many of the self-proclaimed
"experts" said that Livermore's X-ray laser would never work. Well, it turns out they were WRONG!!!
We now even have table-top X-ray lasers:

https://www.llnl.gov/str/Dunn.html

Actually, the plans are to have the reactor fire about 10X per second. The reactor doesn't have
to go from 100M degrees to -250 degrees. Where did you get that idea? The only thing that needs
to be at those temperatures is the fusion capsules - NOT the entire reactor - and you got the
temporal gradient wrong. It goes from -250 degrees to 100M degrees - and that certainly IS
possible given the energy released. Why do you "think" the capsule can't do that?

As I told you last time - and you've evidently failed to absorb the information - the lasers are NOT
a few feet away from the target. They are hundreds of feet away. You do know that laser light
can propagate a fair distance - you don't need the laser amplifiers right next to the target.

If what you are saying was true - we'd destroy NIF the first time we fire it. That's not going to
happen.

Why don't you read up on ICF - because you really don't know what you are talking about.

It sounds like the clap-trap that comes off the anti-nuke websites.

Dr. Gregory Greenman
Physicist
Morbius
#147
Jun15-09, 04:06 PM
Sci Advisor
P: 1,160
Quote Quote by sloughter View Post
Do you really think that you can isolate lasers from the explosive force of a 100 pound stick of dynamite going off a few feet away?
sloughter,

Why not? You just need a big volume to contain the energy - like the target chamber at NIF.

LLNL does that type of testing with normal chemical high explosives all the time at HEAF -
High Explosives Applications Facility.

High Explosives are test-fired in big tanks - and some of the diagnostics are lasers. So there's
no problem isolating an explosive of modest size [ not a huge truck bomb ] from the environs.

https://wci.llnl.gov/fac/heaf/Media/jpg/1Ktank001.jpg

It's not like you don't know what the yield of the capsule is - and you design the facility to
tolerate it.

Dr. Gregory Greenman
Physicist
Morbius
#148
Jun15-09, 04:11 PM
Sci Advisor
P: 1,160
Quote Quote by sloughter View Post
Do you really think hitting a stationary target has any relevance to hitting a moving target? Hitting a static target is comparable to hitting a missile on a launch pad as opposed to hitting it in flight.
sloughter,

Except you know EXACTLY the trajectory of the capsules. One design has the capsules attached to
a wire guide that traverses the target chamber. It's like a miniature version of a cable car - like they
have at ski slopes. The capsule isn't in free flight like a missile - it has to be where the cable constrains
it to be - so it has to be along the cable. Since you are also pulling the cable - you know how far along
the cable the capsule is - and that gives you the location of the capsule.

Don't you know where a cable car is at a ski slope if someone has told you how much cable has been
played out since the car left the terminal building?

Dr. Gregory Greenman
Physicist
mheslep
#149
Jun15-09, 05:02 PM
PF Gold
P: 3,098
Quote Quote by Morbius View Post
sloughter,

Except you know EXACTLY the trajectory of the capsules. One design has the capsules attached to
a wire guide that traverses the target chamber. It's like a miniature version of a cable car - like they
have at ski slopes. The capsule isn't in free flight like a missile - it has to be where the cable constrains
it to be - so it has to be along the cable. Since you are also pulling the cable - you know how far along
the cable the capsule is - and that gives you the location of the capsule.
...
The cable must also be obliterated with the shot. Then what? Cable per shot? Just curious.
Morbius
#150
Jun16-09, 08:25 AM
Sci Advisor
P: 1,160
Quote Quote by sloughter View Post
Last thing I read was that MIT has gotten $15 billion for their hot fusion program and a total of $20 billion has been spent on the hot fusion program in this country so far.
sloughter,

WAY WAY WAY WRONG!!!

MIT's effort in fusion may be on the order of a few million NOT a few billion. I think you've confused
millions and billions. BY FAR - the major effort of the magnetic fusion research has been at
Princeton. The Princeton Large Torus [ PLT ] and the Tokamak Fusion Test Reactor [ TFTR ] have
both been at Princeton. The Dept. of Energy established one of its national laboratories at
Princeton - the Princeton Plasma Physics Lab [ PPPL ]:

http://www.pppl.gov/

There's no national lab scale effort at MIT. MIT runs a small tokamak called "Alcator". The MIT
effort is on the order of a few million. Again, I think you didn't keep "millions" and "billions" straight
in your reading.

The budget for a big national lab like Lawrence Livermore is 1 Billion / year. Lawrence Livermore
get that $15 Billion in a 15 YEARS!!! That's to run the WHOLE LAB!!!

The fusion effort at MIT is one small tokamak and may have consumed a few million dollars.

Again, I would posit you've been sloppy in your reading and confused millions with billions.

Dr. Gregory Greenman
Physicist
Morbius
#151
Jun16-09, 08:35 AM
Sci Advisor
P: 1,160
Quote Quote by sloughter View Post
To suggest as you do that no new energy fields would develop in the next few decades to a century that would make hot fusion irrelevant is specious reasoning.
sloughter,

NOT AT ALL!! Evidently you evidently can NOT or won't do the calculation of how much energy
is available via hot fusion.

First - there's no such thing as "new energy". We know and can account for ALL the potential energy
sources. Some like nuclear fusion - we don't know how to tap yet - but we know how many atoms
of deuterium there are; and we know how much energy we can get from fusion.

We know how much energy there is in sunshine. We know how much energy there is in wind.

You can calculate the energy potential. The fact that you make the specious arguments that you
do tells me that you have NOT done the calculation. You are either unwilling or unable to calculate
the true energy potential available - so you resort to nonsensical handwaving.

Yes - I know how much energy there are in storms like hurricanes. Did you actually "think" you
were telling me something I don't already know?

Dr. Gregory Greenman
Physicist
Morbius
#152
Jun16-09, 08:51 AM
Sci Advisor
P: 1,160
Quote Quote by sloughter View Post
L
The size of the deuterium/tritium particle is the size of a small piece of gravel. How precisely do you attach a "cable" to it? At or near absolute zero every metal behaves brittlely
sloughter,

OH BROTHER - don't you ever do any research before spouting off??
As usual - you don't know what you are talking about.

As for attaching a cable to a particle the size of a small piece of gravel - child's play. Have you
ever seen videos of how Intel and AMD make CPUs? The processors have these tiny, tiny, tiny,
little contacts WAY WAY smaller than a small piece of gravel - and a machine that acts like a
sewing machine connects those tiny little contacts to the upper end of the little pins on the bottom
of the die that holds the microchip with a slender gold thread.

You "think" there is a "problem" connecting a pea gravel sized pellet to a cable?
That has to be one of the dumbest responses I've seen on this forum.

Additionally, we won't be dealing with metals anywhere near absolute zero. The only component
that has to be extremely cold is the deuterium. The pellets may / may not have deuterium ice.

Surrounding the deuterium ice is a capsule which is essentially plastic. So the temperature on
the outside of the plastic won't be as cold as the deuterium ice because the plastic is a fairly good
insulator.

That plastic capsule is then encased in a hohlraum - little cylinder that the lasers heat in order to
generate the drive that implodes the capsule:

https://wci.llnl.gov/org/ax/projects/phohlraum.html
https://lasers.llnl.gov/programs/nic...ma_physics.php
https://publicaffairs.llnl.gov/news/...05-12-02p.html

The hohlraum is the thing that needs to be attached to the cable - and it's not going to be near
absolute zero in temperature.

Additionally, who said the cable was going to be made out of metal?

Your "motis operandi" here seems to be to think up the dumbest way something can be done -
and then rail against how it won't work. Yes - the stuff you come up with won't work - but the
designs that people who know the physics will.

Dr. Gregory Greenman
Physicst
russ_watters
#153
Jun16-09, 07:35 PM
Mentor
P: 22,297
Sorry, I haven't been paying attention to this thread. We do not allow crackpottery here. In particular, crackpot sources of information, such as the referenced sites. Thread locked.

Sloughter, please reread the forum guidelines before continuing here.
russ_watters
#154
Jun19-09, 12:52 PM
Mentor
P: 22,297
I've deleted crackpot and conspiracy theory posts and responses and reopened the thread. Apologies to those who lost time to deleted responses.

Lets keep the thread on point and, more importantly, scientific.
joelupchurch
#155
Jun19-09, 06:35 PM
P: 149
IFR Question.

I was writing up my ideas for replacing Yucca mountain and I wrote that a fuel reprocessing facility should co-located with the storage facility and also an IFR to handle whatever can't be reprocessed. What exactly would be leftover after that? Would any of it have a long half life? How much waste would we talking about per TWH?

If you want to see what I wrote, use the link and go to section 2.

http://www.anupchurchchrestomathy.com/2009/06/upchurch-american-energy-act.html
signerror
#156
Jun19-09, 10:08 PM
P: 223
Quote Quote by joelupchurch View Post
How much waste would we talking about per TWH?
Since there is a one-to-one mass correspondence between fissile material and fission products (minus the tiny fraction of binding energy that is lost), there is a fixed ratio of the mass of fission products to energy generated, for each fissile isotope. For a U-238/Pu-239 closed cycle, it would be about 45 kg/TWh(thermal), where 199 MeV is the energy per fission of a Pu-239 nucleus, and the TWh is of heat produced (not electricity). So for a 50% efficient high-temperature reactor (say), it would 90 kg/TWh(electricity).

So this is the absolute minimum spent fuel waste for any fission reactor. A fast reactor with full reprocessing (like the IFR system) would come close to this.

In an ordinary once-through reactor, there is a lot more waste. For example, the new French EPRs have a (design) burnup of 70 GW-days per ton fuel, which corresponds to spent fuel mass of 595 kg/TWh(thermal) or 1,653 kg/TWh(electric) (so, 26 tons/year). But only a small fraction of this is fission products, corresponding to the same mass fraction which was fissioned (about what, 5%?). The rest is mostly harmless U-238, and a tiny fraction of synthetic actinides created by neutron capture (Pu-239 and beyond). So with full reprocessing and MOX fuel burning (as the French do), the once-through light water reactors produce about the same mass of high-level waste as fast reactors - although since it has a much larger amount of transuranic isotopes, it is much longer-lived.

I hope the experts here will correct me if I've misunderstood something.
joelupchurch
#157
Jun20-09, 01:52 AM
P: 149
I obviously don't understand. What I read is that 95% of the spent fuel is Uranium or Plutonium and all those isotopes are fissile or fertile and can be reused. Most of the rest is actinides that can be burned in an IFR. It looks to me like the only thing that needs to be disposed of are the actual fission products, but it isn't clear what those products are and how long they are dangerous.

From what I read on the LFTR, it looked like you could get a GWe Year out of 1 ton of Thorium, so the actual waste product would be 1 ton or less. I was hoping to get a similar result with uranium, albeit with more hassle.

From what I read about spent fuel, they amount to about 1 ounce per person per year, so I was hoping to get it down to a couple of grams a year using all the technology available.
signerror
#158
Jun20-09, 06:17 AM
P: 223
Quote Quote by joelupchurch View Post
From what I read on the LFTR, it looked like you could get a GWe Year out of 1 ton of Thorium, so the actual waste product would be 1 ton or less.
Yes, 1 ton/GWe-yr is about 100 kg/TWh. (There are 104 hours in a year.)

It looks to me like the only thing that needs to be disposed of are the actual fission products, but it isn't clear what those products are and how long they are dangerous.
Hundreds of years.



from http://www.nea.fr/html/ndd/reports/2002/nea3109.html

The third bold line is fission products (FPs). The individual examples shown are Strontium-90, Cesium-137, Technetium-99, and Iodine-129.
joelupchurch
#159
Jun20-09, 01:25 PM
P: 149
Thanks signerror, I like the graph. It looks like most of the fission products are safe in 400-500 years, but there are some long half-life isotopes that need to be separated out and handled differently.

That would mean that each fuel recycling would produce some fission products that need to separated and stored. I guess one ton a year for a GWe electrical plant isn't too bad.

I calculated what a GWe coal plant would put out per year and came out with over 7 megatons of CO2 and 600 to 700 kilotons of other waste, including 12 tons of thorium and 5 tons of uranium.


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