[zapkitty]

Mike Weber Goodenow wrote: I saw somewhere that it appears that D-T fusion processes can be used to clean up nuclear waste from current nuclear power plants and nuclear weapons. Cut it by 90% or more.

If true, and if it’s cost-effective, this would be of very significant interest to federal policymakers, including Congress, and could help accelerate fusion R&D funding.

First, is this true?

Second might it be cost-effective?

Third, has anyone thought about the use of aneutronic fusion to clean up fission-produced nuclear waste, comparing and contrasting aneutronic with D-T for this purpose?

BTW… did you perhaps mean your topic title to be “Fusion Cleans Up Nuclear Waste from [em]Fission[/em]”…?

[zapkitty]

Mike Weber Goodenow wrote: Does aneutronic fusion require a high-repetition long-lasting laser?

Nope. Not required.

Can a laser be used? Possibly. NASA engineer John Chapman has proposed a laser-based pB11 thruster design but the oligarchs have banned fusion projects at NASA proper so if it can be built it’ll have to be built somewhere else…

A thread on it here:
https://focusfusion.org/index.php/forums/viewthread/922/

[zapkitty]

Tulse wrote: “Aneutronic” refers to the nature of the fusion reaction, namely that it produces no (or, more accurately, very few) neutrons. This characteristic is in principle orthogonal to the method used to get the nuclei to fuse (although aneutronic reactions generally require higher energies to cause fusion).

(This is all my understanding — someone else may be able to correct any errors I’ve made.)

That’s it. Aneutronic fusion is defined as when neutrons carry no more than 1% of the total released energy. Essentially means that if a particular reaction generates any neutrons at all they would be a side-effect of the main fusion process and thus would be an annoyance instead of something required for net power generation.

And as the neutrons are <1% of the total power that means no neutron activation of reactor materials… and thus no nuclear waste.

[zapkitty]

Tulse wrote: As I understand it, aneutronic fusion wouldn’t be much use for cleaning up fission waste, since what you want to do with such waste is transmute the problematic nuclei, which entails a neutron source.

Nope… neutrons can be generated without a neutronic fusion power source. In fact anyone can generate neutrons. All you need is electricity.

For the task at hand, transmuting the waste from nuclear fission… artificially “aging” it into safer forms… you’d just need a lot of cheap, safe power.

… and it’s FF to the rescue again! 🙂

Aneutronic fusion would actually be both safer and cheaper than neutronic fusion in this task and FF would enable flexibility and portability on top of that.

Instead of the concatenated expenses and increased hazards of trying to transport and integrate the nuclear fission waste into the fusion fuel process, FF units would power onsite particle accelerators wherever the waste happens to be located.

So you’d swap the costly neutronic setup of tritium and neutrons and steam and turbines and the extensive modifications to the fusion fuel cycle… for a particle accelerator and on-site waste processing wherever the fission waste happens to be.

The task must be done with whatever tools we have available. The problem is yet another Sword of Damocles hanging over our heads…

(passing extraterrestrial: “Errr… quite a blade collection you people have up there on the ceiling…”)

… but using FF units for the task would be a win-win-win situation.

[zapkitty]

Duke Leto wrote: No, zapkitty’s right. The current Desal process is obviously too equipment intensive by comparison to just boil and coalesce. If he’s right then 50 cents might not be unrealistic.

Then and again I’m barking mad.

You ARE mad… it would be much cheaper 😉

The following calculations are BotE, don’t count plant costs (but those will be dirt cheap compared to current desal gear) and assume 100% efficiency in applying the FF heat to the water… but this will still get you within an order of magnitude or two of the cost:

amount water at 20 degrees c (kg) 1000
(1 metric ton seawater)

spec heat water (kj/kg) 4.186
latent heat (kj/kg) 2260
delta t (c) 80

1st step raise to 100c (kj) 334880
2nd step vaporize (kj) 2260000
total (kj) 2594880

FF kilowatts thermal (kwt) 7000

process time (sec) 370.7
process time (min) 6.18

Yep, even the waste heat from a 5 MWe fusion reactor takes over 6 minutes to boil away one ton of water.

daily water output (tons) 233.07

kwh in a day 24
FF elec cost kwh (cents) 0.2
desal power cost per day (cents)… 4.8

power cost 1 ton water (cents) 0.021

Lerner-hakase has it right… FF fusion desal makes water problems simply go away.

[zapkitty]

delt0r wrote:
Bremsstrahlung is the main source of xrays and is very definitely wide spectrum. There may be some line radiation from impurities, but this push the losses up massively and is typically avoided.

Well, “not wide-spectrum” was in response to opensources question about whether, since the plasmoid emitted x-rays, if it also emitted spectra other than x-rays in quantities sufficient to affect the overall power output.

delt0r wrote: `The xrays are wide spectrum, there is no doubt about it.

And there we get into details of the onion… which is why I stuck to generalities 🙂 I do wonder how the magnetic quantum effect will affect the x-ray output spectra with pB11 but I guess we’ll have to wait and see…

[zapkitty]

opensource wrote:
Vansig said that one-third to one-half of the total output is x-rays. Doesn’t this mean that the output in other spectra would be significant?

No. The x-rays are produced by a specific process in the plasmoid called bremsstrahlung and in an FF DPF plasmoid that process produces mostly x-rays. The specific energies of the x-rays generated are governed by the fuel, the temperature and the nature of the plasma confinement. The plasmoid is not a wide-spectrum energy source.

If you are looking for energy to scavenge to achieve fusion then as far as FF DPF output power is concerned you would have the beam of charged particles, a pretty omnidirectional burst of x-rays and the heat. An FF unit would be very efficient.

Will other things be produced? Yes, but not enough of anything to affect the balance of power.

Bremsstrahlung, often referred to as “brem” or “brems” in fusion-speak 🙂 , actually cools the fusing plasma and is unwanted. It was initially supposed that brem losses would stop a DPF plasmoid from achieving a self-sustaining plasma burn, or “ignition”, and thus make practical DPF power generators impossible. But Lerner-hakase and company realized that the extreme magnetic field in a DPF core would be strong enough to cut down on brem losses… theoretically at least enough to enable a burn and move a practical DPF power generator from “impossible” to “perhaps feasible.”

opensource wrote: How do I find the proportions of the various different types of energy outputs?

If you are speaking of things that would affect the power balance, which is what I gathered from your questions, then it seems that you are looking for something that isn’t there.

opensource wrote: Also, are the x-rays all the same frequency? If not, then doesn’t this create an issue for capturing them.

The x-ray pulse would not be monochromatic but the spread of energy would be governed by the factors I noted above. And as the “onion” would have to be composed of many thousands of layers of metal foil to work it would, by its nature, be engineered to capture a wider spectrum than lower-energy photoelectric converters.

opensource wrote: I take it this “pulse of charged particles” (loose language in my opinion) is mostly x-rays

No, it’s a pulse of charged particles. In a beam no less 🙂 These would be alpha particles for the most part.The brem x-rays are an annoyance in that they have to be reduced as much as possible and what cannot be eliminated needs to be harvested.

opensource wrote: In theory, what charged particle or EM frequency would be the most ideal for converting into electrons using photo-voltaics?

side note: The onion is photoelectric in nature… photovoltaics are a branch of photoelectrics. Although I’ve made the error myself when speaking of FF it’s not quite the same thing.

Ideal? From an FF? Converting the beam would be a few more percent efficient than converting the x-rays. The heat cannot be efficiently converted to electricity with current tech.

[zapkitty]

opensource wrote: Sorry that’s not really what I’m asking, and I don’t really understand what “beam” stands for. My questions from post numbers 10 and 12 are what I’m trying to understand – sorry for being thick-headed.

Then the google talks video would be very helpful in that case.

Very short version; A DPF produces a brief plasmoid. As this plasmoid collapses it emits a beam. In a Focus Fusion DPF the beam would be composed of helium nuclei, alpha particles, produced from the fusion of p and B11 in the plasmoid.

This beam of fast-moving charged particles is electricity just waiting to be tapped.

The plasmoid also produces x-rays, which again can be converted to electricity at high efficiency.

And the plasmoid emits heat. 7-8 MWt at about 600 degrees wouldn’t be too great for spinning turbines but would be great for heating the neighborhood buildings in winter, endless applications as industrial process heat and also for evaporating seawater for desalination. If the heat is not wanted at all then it can be sent to an air-cooled heat exchanger.

The energy total of everything else produced by the FF wouldn’t amount to very much compared to the beam, x-rays and heat.

[zapkitty]

opensource wrote: There seem to be some basics to straighten out here. Can you reply to my questions as well zapkitty?

From the google tech talk: after losses (thermodynamic efficiency is estimated to be ~42%) the net output would be split thusly:

x-ray over input .81
beam over input .98
x-ray + beam over input 1.79

[zapkitty]

vansig wrote: if i recall correctly, the model, with various different parameters, predicts from about a third to half of input energy being emitted in x-ray.

the 80% figure for the onion capturing the x-rays might be unrealistic. if we capture its energy with photo-voltaic cells, we can get 10 to 20%. if we capture its energy with a heat engine, we can get about 55%. (but i have not fully explored the possibilities).

Nope. The efficiency of photoelectric conversion of a photon is directly proportional to the energy of the photon. That’s why infrared-range photoelectric converters are not nearly as efficient as visible-range converters. X-ray conversion will be even more efficient than visible light conversion. The trick is catching enough of them first.

There’s no great mystery about X-ray photoelectrics… it’s just that before FF there was no reason to investigate it as a power source.

And the heat from an FF unit, once removed from the core, would be what is considered “low grade” heat in industrial terms… not efficient for turbine use.

vansig wrote: the present set of parameters for attempting break-even is…

… not being attempted for FoFu-1 (what a name 🙂 ) The only coils in the drift tube are for measurement, not power conversion.

What [em]will[/em] be attempted is a demonstration of scientific feasibility. If they can show that an FF-style DPF produces enough extra energy to make a generator feasible then it’s game, set and match… and without having to build an actual generator on top of everything else they have to do.

[zapkitty]

asymmertic_implosion wrote:
I agree that marketing and PR are important but I suggest staying away from textbooks…

But I swear the textbooks followed me home on their own!

More seriously, complying with your suggestion is gonna be difficult… Houghton-Mifflin keeps texting me asking for articles on aneutronic fusion’s influence on 16th century Ottoman Empire merchant ship designs…

asymmertic_implosion wrote: … and regulators.

Too late… FoFu-1 haz dun bin regulated 🙂

asymmertic_implosion wrote: All I ask is show me the data before claiming fusion will change the world. I’ve heard it too many times before. 🙁

We are saying that fusion power would change the world… and we are correct.

We are saying that aneutronic fusion power would have an even greater impact than neutronic fusion… and we are correct.

And we speculate on how a successful FF unit would affect the world… but we don’t claim that it’s anything other than speculation.

Then again, it doesn’t take a genius to understand that inexpensive and sustainable aneutronic fusion power would change the world and the very nature of the FF unit will define the how some of those changes would occur.

As for these particular threads: the fact is that a successful demonstration would have staggering implications for humanity. The magnitude of those implications is no reason not to discuss the potential effects of success.

Indeed, it’s probably a good idea to start talking about these things early…

[zapkitty]

asymmertic_implosion wrote: That is my point. Lerner-Hakase have gone over them in paper. I have no problem with speculation and research. Optimism should be the norm for those working on any new technology. Great potential is the reason to take on new things. However, many research papers are not going to convince regulators.

Regulators already have defined regulations for all aspects that an FF unit would entail.The simple fact that no radioactive fuels are involved and the compete absence of radioactive waste greatly simplifies life for all concerned.

asymmertic_implosion wrote: To a regulator, FoFu-1 is a new “thing” that they don’t understand. If they don’t understand something, they don’t let it operate.

They won’t understand an electrically-powered radiation source whose operational mode is “fully shielded at all times”? Sorry, but even the nuclear density gauge market has a rental segment now and [em]those[/em] are actually designed to emit radiation into the public space.

Would FF units be regulated? Certainly… but they would be covered by existing regulations.

[zapkitty]

Just a note: you seem to be churning over a variety of things that Lerner-hakase and company have already addressed either in their papers or on the forum… a sort of “best of” list of skeptic talking points.

Nothing wrong with questions, of course, but you shouldn’t be surprised to learn that they’ve already been discussed and either do not seem to apply or are not show-stoppers.

As for your view on what should and shouldn’t be discussed at this time… insofar as Focus Fusion is concerned it would be quite irresponsible not to speculate 🙂

[zapkitty]

Last I heard estimated FF electrode lifetime was about a month, revised downwards from an earlier estimate of about 3 months.

Given electrode recycling, wear isn’t expected to be a big impactor on cost or performance unless the electrode lifetime gets a lot shorter is than currently thought. An apt comparison would be the wear and maintenance costs of a gas turbine generator and associated gear… and that’s a comparison that the turbine just can’t win.

[zapkitty]

dennisp wrote: The bill in question does allow a higher limit when companies supply audited financial statements.

And it wasn’t exactly the small startup companies that crashed the economy and wiped out investors in 2008. The bill makes no changes to regulations of large companies or financial institutions.

If the bills are successful then I would be very happy to invest in LPP, but if anyone thinks that any new securities law will not be abused then they haven’t been paying attention.

As I said: it is good that legalizing alternatives such as crowdfunding is being considered… but that doesn’t change the fact that current securities laws were written to serve a much-needed purpose.

And aside from the rather panglossian cheerleading on startupexemption.com the reasons for the existence of those laws still apply. The securities markets of the 1920’s would be as much of a disaster today as they were in 1929. The current misbehavior of less-than-upright companies that is documented daily in investor forums worldwide can leave no doubt of that.

People lie and in the financial world if something can be misused then it will be misused… and thus regulation.

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