CSvax:svb@pur-ee.UUCP (09/24/83)
My personal opinion about nuclear energy ('convential' reactors) is that
its usage is untolerable, because the waste problem is unsolved.
My hope was (is?) that nuclear fusion (plasma....) would not cause these
problems. And that is what I would like to ask - is there anybody who
can comment on the waste problem in connection with nuclear fusion power
plants?
I finally would like to draw your attention to an article in the October
issue of the Scientific American - which has an article about nuclear fusion,
but which does not really answer my question. What is the amount of
waste produced??
Stephan v. Bechtolsheim
Purdue CShalle1@houxz.UUCP (J.HALLE) (09/26/83)
I really wish people would not spout off on subjects about which they know nothing. Fusion waste? If you had read and understood the article, you would realize that there is no waste, at least none that was any trouble. Fusion works by "fusing" together several hydrogen molecules, either as pure H in some isotopic form, or water. (There are other potential materials also, but the principles are the same.) No radioactive materials are produced by the process that are not contained. No toxic chemicals are produced. An extremely clean operation. Unfortunately, it also requires conditions we cannot produce yet. Don't expect anything until next century. As for the waste problem with fisson. This problem has been solved many times and the solutions have been known for years. The problems are pure and simply POLITICS and FEAR. The thought of nuclear anything terrifies people (witness your question that prompted this reply). Unless you can guarantee 100% (make that 100^100%) that the waste can't escape, even if it is harmless, people will scream. And screaming people catch politicians ears. There is absolutely no problem disposing of nuclear wastes safely. What makes this fear of nuclear waste so absurd is that there is no noise whatsoever about waste from other forms of energy. The worst offender is coal. The products of coal mining, milling, and use are among the most toxic substances known to man. And there has been little done about disposing of these wastes safely. One day's production of coal waste products is far more toxic than all the nuclear wastes produced to date. These wastes are then just buried or left sitting in slag heaps. (Drive through the northeast Pennsylvania countryside some time to see how these wastes are "disposed".) But coal is not "dangerous" so it is not a problem. If you can figure out and implement a way to dispose of those wastes as cleanly and safely as has already been done for nuclear wastes, then and only then will I entertain your comments about nuclear waste.
dgary@ecsvax.UUCP (09/26/83)
Oh, boy, nuclear flames! I have run into a good many people who are upset about nuclear power because of the "waste disposal question". There are a good many reasons to be concerned about nuclear power (and coal power, and hydroelectric power, and windmills chewing up birds, etc. etc.), but I find the much-ballyhooed waste-disposal problem a non-issue when it comes to being for or against nuclear energy. Suppose that tomorrow morning at 0900 EST we shut down forever all nuclear reactors on Earth (perhaps keeping one or two for medical and research purposes). What would happen to the existing waste? Would it become offended and leave? Failing that, it seems the problem is with us, nukes or no nukes. We HAVE to solve the problem. By the by, only about half of this high-level, long-lived waste is from power production if memory serves. Since there have been no new nuclear plants begun for sever years, the few plants still a-building are not worth worrying about when it comes to waste. I'm not as comfortable with the question of major radiation leaks from a reactor. It's encouraging to note that reportable (and often unreported) foulups happen at commercial sites worldwide on a very frequent basis, but so far no disaster seriously affecting the general public has been observed. Even the most pessimistic projections of long-term deaths from Three Mile Island suggest if we wanted to save lives by banning something, we'd be loads better off banning Labor Day Weekend. I repeat: I am not completely comfortable with nuclear power (or with any means of power production - I'm not in love with burning up fossil fuel, building dams everywhere, you name it). The whole issue needs careful study and intelligent thought. What it does NOT need (flame throwers at the ready) is self-appointed experts on engineering with degrees in phys ed or whathaveyou deciding that they bygod KNOW what's best for the rest of us and, not content with cumbersome annoyances like the democratic process and similar, elect to occupy buildings and lie down in highways and get arrested and generally play act the role of the REAL martyrs like Ghandi et al who resorted to civil disobedience as a last resort instead of a hobby. (Please note that this is directed at no one on this net.) Finally, on fusion power: Most fusion reactions being studied emit neutrons which in turn causes transmutation of the walls of the reactor. (Neutrons cannot be contained in a "magnetic bottle", of course, since they are electrically neutral.) The neutrons themselves are easy to stop, but the resulting isotopes may be quite dangerous, depending on the material used for shielding. There is an alternative to both fission and fusion, but I confess I cannot recall much about it save the fact that only a handful of physicists are working on it, many think it's not practical, but if it were, it would be essentially radiation free and would make everybody happy or something. Seem to recall it involved lithium fusion or something...
dgary@ecsvax.UUCP (09/26/83)
addendum... I meant to say that supposedly wonderful substitute for fusion was lithium FISSION (or something along those lines). Yes, I know you aren't supposed to get energy out of fissioning anything lighter than iron (cold iron, the master of them all). But there are indeed a few non-spontaneous splittings (i.e. n + Li --> n + something) that give up a little energy. I read something about this in Technology Illustrated, I think... If anyone is really interested, I'll see if I can dig the thing up.
gjphw@ihuxm.UUCP (Not really but: Patrick H. Wyant) (09/26/83)
While it has been awhile since I have seriously discussed and performed
homework problems in nuclear physics, I would still like to enter the upcoming
fray on nuclear fusion. Too often, fusion is presented as the savior to our
large-scale, long-term energy needs. It is supposed to be tasteless,
odorless, colorless, harmless, and nonfattening. Not being an expert in
plasma fusion, I am unable to dwell in great detail on the mechanisms, but I
can tell you what I have heard that makes sense.
Hydrogen fusion is the mechanism assumed to be in operation in the Sun,
despite the observation that the neutrino flux is not as predicted. The
fusion of four hydrogen atoms into a helium yields lots of energy, which we
see as neutrinos, gamma rays, and heat. The conditions that allow such fusion
to occur are difficult to realize without the high forces that can exist in a
star (e.g., for gravitation or densities). These conditions are sufficiently
difficult to achieve on Earth that the fusion of hydrogen is probably not the
best route to take for controlled power generation. Either deuterium or
lithium would be fuel more suitable for terrestrial fusion. Both are fairly
plentiful on Earth.
However, the use of either of these two fuels, or perhaps a combination of
the two, gives results that are not exactly the same as the hydrogen fusion
cycle of the Sun. The use of either deuterium or lithium does not have as
high a yield as hydrogen. Also, the use of these fuels generates a sizable
number of neutrons (high neutron flux) as an additional byproduct of the
fusion. This neutron flux contributes to the heat given off by the fusion
reaction, and will act to make the containment vessel for the fusion
radioactive. One of the oft overlooked aspects of fusion research is how to
make the containment vessel resist the corrosive effects of neutron
irradiation, and how to dispose of the material (or how often will it have to
be replaced).
As stated by J. Halle (houxz!halle1), the radioactive wastes produced by
nuclear fusion are more easily contained that those from fission. If some
problem occurs, the fusion process is quickly quenched and the only lingering
radioactive material is the containment vessel. The fission process makes
lots of radioactive solids and liquids, while fusion is expected to affect
only solids (mostly metals). Unfortunately, I have no information as to how
the quantity of radioactive materials from the two processes compare. What I
have heard is that the radioactivity from nuclear fission covers a wide
spectrum of half-lives, while the fusion-induced radioactivity is almost all
long-lived. Fusion will produce radioactive metals that cannot be further
refined and must be safely stored for many centuries.
The Scientific American article, mentioned by S. Bechtolsheim (pur-ee!svb),
fails to discuss much about the radioactive wastes from the fusion process
because they are considered to be more manageable than those from the fission
process, and because not much attention has been given to it. From what I
have read, there is little effective protection that can be given to the
containment vessel to protect it against neutron corrosion. And, that is the
primary source of radioactivity in the fusion process.
Further comments?
Patrick Wyant
AT&T Bell Laboratories (Naperville, IL)
*!ihuxm!gjphw
P.S. I must also agree with J. Halle in his complaint about how nuclear
wastes are treated. Often, they are used as pawns in a political power
struggle between different interest groups. At the same time, wastes from
more conventional power sources (e.g., coal) are overlooked and sometimes
ignored (e.g., acid rain) because they may be too familiar.els@CSvax:Pucc-H:pur-phy.UUCP (09/27/83)
Nuclear fusion does indeed leave a form of radioactive waste.
Neutron activation will leave the reactor core in a fairly high
state of radioactivity. In a large reactor which will be used over
many years, this isn't much of a problem. However, some companies
have expressed plans to build lots of little reactors that are
expected to 'burn out'(i.e. have the magnetic field windings fail)
in less than a year. If these reactors can be mass produced, it will
be cheaper to just use them, recycle some of the materials, and throw
the rest away!! While these cores won't be nearly as hot as a fission
core, they will still need to be isolated from the environment.
Current thinking is that the can be encased in concrete and dropped
into an old mine. In spite of this, it should be realized that, even
getting rid of old fusion cores represents a waste problem that is
orders of magnitude smaller than the problem of fusion waste.
By the way, the same guy who designed that 'throwaway' tokamak
also says that once fusion has progressed to hotter(thermally) reactions,
that fission and toxic chemical waste could be dumped into one of these
fusion reactors. The neutrons from the fusion would break high-level
radioactive waste into its low-level decay products(thereby eliminating
the storage problem) and the chemical waste (usually complex molecules)
would be broken down to its constituent atoms. Neat, huh?
els[Eric Strobel]
pur-ee!pur-phy!elsShinbrot.WBST@PARC-MAXC.ARPA@sri-unix.UUCP (09/28/83)
I am also interested in the waste issue. Particularly, what becomes of the endless supply of neutrons that fusion generates??? - Troy
Shinbrot.WBST@PARC-MAXC.ARPA@sri-unix.UUCP (09/28/83)
I will take your advice and not be irritated by your comment that none of your derogatory comments are aimed at anyone on this net. I do, however, find your remarks about waste-disposal being a non-issue to be a wee bit infuriating. I would like to remind you that people have been opposing nuclear fission for some time now. It was not yesterday that we brought up the issue of nuclear waste disposal. Therefore those of us who have been involved in investigating problems and alternatives can be excused for finding your remarks peculiar. At what point, pray tell, does the non-issue become relevent? Just how much waste would you like before you choose to become concerned? We were calling for an end to this domestic nuclear proliferation 10 and more years ago. The uranium presently driving nuclear plants was still in the ground then. If we had shut the plants down then, most of the waste would not be around. Your suggestion, therefore, that we not worry about waste, that we not worry about the few plants still a-building make me think that you are less than impartial and rational on this issue. As for the rest of your letter, I cannot imagine where you get your information or what has gotten you so exercized. Anyone on any side of the nuclear issue will tell you that almost without exception, the democratic process has nothing whatever to do with the licensing or implementation of nuclear power plants. The local governing bodies in most municipalities, including yours I expect, institute an appointed body of utility commissioner(s). This body decides the rates and economic recourses available to nuclear utilities. The physical constraints applying to the nuclear plants are established by the Nuclear Regulatory Commission - not an elected body. The emergency procedures pertaining to the nuclear plants are dictated by the Federal Emergency Management Agency - not an elected body. The financial decisions to go nuclear are made by banks and banking groups, which are not elected. So next time before you harp about phys ed majors play acting as a hobby, THINK, willya???
KING%KESTREL@sri-unix.UUCP (09/29/83)
From: Richard M. King <KING at KESTREL>
[Troy]
what becomes of
the endless supply of neutrons that fusion generates???
I recommend an article in October's Scientific American.
The "common" form of fusion uses one duteron (H2) and one triton
(H3) to make an alpha particle (He4) and a neutron. This neutron runs into
a body of common Lithium (mixture of Li6 and Li7) and does one of two
things: Li6+N->H3+He4, or Li7+n->H3+He4+N. The latter reaction can't go on
forever because it requires a fast neutron and produces a slower one, and
because eventually a Li6 will get lucky. This is where new tritium comes
from.
The only nuclear waste from a fusion plant is caused by neutrons
making material such as the reacter vessel radioactive. This does happen,
but (according to the article) the volume can be considerably reduced by
choosing construction materials carefully and by choosing good isotopes of
(for example) alloying materials. These wastes are low in volume (after
all, it's a parasitic effect), and they tend to decay quickly.
I've been wondering about the matter and I would think that a
tritium leak would be pretty benign. First, tritium is hydrogen and it
would tend to float away. Then it becomes water vapor. Life doesn't tend
to absorb water vapor; it dissipates it. Then when it condenses it has a
lot of room to hide. Contrast this with iodine, which doesn't get diluted
much once it enters the body. By the way, one thereputic measure against
fallout is to take iodine pills to crowd out the radioactive iodine.
Dick
-------WELD%MIT-OZ@sri-unix.UUCP (09/29/83)
Does anyone know what percentage of the nuclear waste that is produced in the US comes from civilian reactors and what comes from making bombs? I seem to remember the figure 95% military. In which case somebody better solve the waste storage problem REGARDLESS of the future of civilian power plants.
howard@metheus.UUCP (09/30/83)
A recent posting was obnoxious AND wrong enough to make me want to respond. "I really wish people would not spout off on subjects about which they know nothing." Me too. [in fusion] "there is no waste, at least none that was any trouble." "No radioactive materials are produced by the process that are not contained." Wrong. All present and proposed fusion devices release both tritium, which can be contained by chemical means but usually is not, and helium-3, which cannot be contained by chemical means. "As for the waste problem with fisson[sic]. This problem has been solved many times and the solutions have been known for years. The problems are pure and simply POLITICS and FEAR." "There is absolutely no problem disposing of nuclear wastes safely." I've heard the claim before that the nuclear waste disposal problem is solved. But no one making that claim has ever been able to describe a solution that I haven't been able to shoot down in minutes. Are you claiming that the problems are solved AND that there are no such problems? Or are you claiming that the problems of POLITICS and FEAR have been solved many times and the solutions have been known for years? :-) I seem to recall General Electric spending about $250,000,000 on their Midwest Fuel Recovery Plant, which was intended to recycle nuclear fuel. I don't believe MFRP ever actually recycled anything. But I digress. Let me mention just ONE objection that I have, that of terrorists having access to nuclear wastes. Many nuclear wastes are active for several tens of thousands of years. Anyone who believes that such wastes can be safely stored for that length of time are very naive about history, politics, sociology, military science, and technology, to name a few areas. ANY storage scheme that we can dream up now MUST be able to defend against the wiles of terrorists using the technology of 5,000+ years in the future! I suggest that no such storage scheme exists, even in theory. If you wonder why I say MUST, consider that a cupful of plutonium, finely enough divided, could cause cancer with probability > .9 in EVERY MEMBER OF THE HUMAN RACE. It's use on a major city would render it uninhabitable for quite some time. For a country which has only been in existence for 200 or so years to think it can safely manage a nuclear waste site for thousands of years is a childish fantasy. "What makes this fear of nuclear waste so absurd is that there is no noise whatsoever about waste from other forms of energy. The worst offender is coal. The products of coal mining, milling, and use are among the most toxic substances known to man. And there has been little done about disposing of these wastes safely. One day's production of coal waste products is far more toxic than all the nuclear wastes produced to date. These wastes are then just buried or left sitting in slag heaps." I am pretty much in complete agreement with you on the evils of coal, but you can't be serious about "no noise whatsoever"! You failed to mention one of the worst by-products of coal burning, namely acid rain. A specially hard problem politically because the effects are geographically distant from the offenders, and it is VERY hard to "prove" that a particular coal plant had anything to do with a particular fall of sulfuric acid. Choosing between coal and nuclear, I might in many cases choose nuclear myself, but that doesn't exonerate nuclear. You seem to imply that it does. It is sad but true, however, that an average coal plant releases much more radioactivity into the environment than an average nuclear plant of the same capacity. The NRC is not allowed to regulate radioactive output from coal plants, otherwise ALL coal plants might have to shut down. "If you can figure out and implement a way to dispose of those wastes as cleanly and safely as has already been done for nuclear wastes, then and only then will I entertain your comments about nuclear waste." Sort of like saying we shouldn't prosecute any rapists as long as there's a murderer who isn't behind bars? Public or private flames cheerfully received, and maybe even answered. Howard A. Landman ogcvax!metheus!howard
dya@unc-c.UUCP (10/02/83)
References: sri-arpa.12111
1 ) An elected body is NOT necessarily the only way to become
involved in the political process
2 ) The administrative bodies you cited have to get their members
from SOMEWHERE. They are not imported from pluto. And those
on either side of the issue could, in theory and practise,
become members of these administrative bodies.
I was merely suggesting that instead of having hot, emotional debates
over the issue with little information, that those truly interested in doing
something about nuclear power, yea or nay, should become involved in the
political process. Once they did so, they then could debate the issue
ON THE MERITS. Those who claim that there is NO WAY for an organised group
to become involved are suffering from anti technological backlash and an
impotency feeling created from same. From an efficiency point of view, I
think that an organised effort d directed at the source of the regulatory
bodies' power would be far more effective. I agree basically with what
you are saying, however, my comment was aimed at the ten zillion members
of the population who oppose nuclear power without having the slightest
idea of the MERITS of the argument.
My comment was one of questoning the methodology of the debate, that's
all.
--Davidabc@brl-bmd@sri-unix.UUCP (10/03/83)
From: Brint Cooper (CTAB) <abc@brl-bmd> HI! Being merely a dumb engineer, I should like to learn more about one of your assertions: that the average coal plant releases more radioactivity than the average nuclear power plant. 1. What kind of radioactivity is released? 2. Who has measured it and where are the statistics reported? Thanks, Brint
Shinbrot.WBST@PARC-MAXC.ARPA@sri-unix.UUCP (10/03/83)
Bravo. On an added point, it is worth noting that many coal deposits contain not inconsiderable quantities of uranium - enough that Esso (now Exxon) carried out a project a few years ago to investigate the cost effectiveness of extracting the uranium from the coal. Hence it has been estimated by Amory Lovins and company that (in normal operation) coal plants emit MORE radio-isotopes than nuclear plants. Nuclear power is indeed untenable, but coal is no alternative. - Troy
abc@brl-bmd@sri-unix.UUCP (10/04/83)
From: Brint Cooper (CTAB) <abc@brl-bmd> Sorry to disagree, but I quote from his message, "It is sad but true, however, that an average coal plant releases much more radioactivity into the environment than an average nuclear plant of the same capacity. The NRC is nnot allowed to regulate radioactive output from coal plants, otherwise ALL coal plants might have to shut down." So I ask again, what is the source of this assertion; who measured the radioactivity, and where is the data reported? Thanks, Brint
mcbryan@cmcl2.UUCP (10/09/83)
The waste aspects of nuclear fusion power are likely to be unpleasant. In general, large numbers of free neutrons escape from the containment area, and need to be stopped. In addition, since these neutrons carry a lot of energy, they have to be stopped in order to make the overall fusion process energy efficient. One of the primary proposals for doing this is to surround the containment area with uranium, - the uranium is converted to plutonium by the neutrons, and the plutonium can then be burned in conventional reactors. The waste aspects of this scheme are to say the least not clean.