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No proliferation risk at all in a tritium fountain full of 14 MeV neutrons? Are you sure you know what you're talking about? These will all be guarded with pse

No proliferation risk at all in a tritium fountain full of 14 MeV neutrons? Are you sure you know what you're talking about? These will all be guarded with pseudo military guns guards and gates just like fission, and monitored by the IAEA. As for radiological safety, see point about tritium. And google tritium leak nuclear plant for good measure. Youre right that there is less radioactivity in fusion plants, but maybe not enough less to really matter.

smaudet 4y ago
"Still, the NRC and industry consider the leaks a public relations problem, not a public health or accident threat, records and interviews show." https://www.ap.org/press-releases/2012/part-ii-ap-impact-tritium-leaks-found-at-many-nuke-sites#:~:text=Tritium%2C%20which%20is%20a%20radioactive,at%20aging%20nuclear%20power%20plants https://www.ap.org/press-releases/2012/part-ii-ap-impact-tri.... And this is why we should not trust any fission-bearing folk. Or apparently fusion-bearing folk either.
- mlindner 4y ago
  Tritium leaks are indeed public relations problems, if done in the very small quantities that would be in a fusion reactor.
  - pfdietz 4y ago
    > very small quantities that would be in a fusion reactor Fusion reactors would involve much more tritium than in a fission reactor. In the latter, especially LWRs, tritium comes from rare ternary fission events. In a DT fusion reactor, T is a primary fuel. A 1 GWe fusion plant will burn about 150 kg of tritium a year. To illustrate how much that is: that quantity of tritium would be enough to raise 2 months worth of the average flow of the Mississippi River above the legal limit for drinking water.
mlindner 4y ago
> No proliferation risk at all in a tritium fountain full of 14 MeV neutrons? Are you sure you know what you're talking about? If you're putting hunks of uranium inside a fusion pressure vessel it'd be really obvious. Tritium itself doesn't have proliferation risk. > These will all be guarded with pseudo military guns guards and gates just like fission, and monitored by the IAEA. No they won't. Because even if you crash a truck into them there's no ecological disaster. > As for radiological safety, see point about tritium. And google tritium leak nuclear plant for good measure. The tritium stored in the reactor will be in the microgram range. > Youre right that there is less radioactivity in fusion plants, but maybe not enough less to really matter. It's several orders of magnitude less. I think that matters quite a bit.
- adrian_b 4y ago
  It is completely premature to claim that the radioactivity will be "several orders of magnitude less". The neutron flux produced by a fusion reactor will be much higher than in any fission reactor, and it must be absorbed in a shield, to produce heat, which will be the output of the fission reactor. Choosing an appropriate material for the shield will minimize the quantity of radioactive material that is created per unit of output energy, but it is pretty certain that the radioactivity will not be "several orders of magnitude less". The best that can be hoped is that it is possible to find a shield material that will produce only very small quantities of long-lived radioactive isotopes, so that, after a storage for not too many years, the radioactivity might decrease to be "several orders of magnitude less". Nevertheless this remains to be demonstrated. For example, any piece of steel present near a fusion reactor would produce copious amounts of cobalt 60, but that would decay to negligible radioactivity after a few hundreds years. Moreover, to ensure the predicted low residual radioactivity, any shield material needs to be free of impurities, which even in very small quantities could produce dangerous radioactive isotopes. The requirements for advanced purification will greatly increase the cost of the structural materials for fusion reactors. However this is not a new problem. Similar requirements are imposed on the structural materials for fission reactors, but the fusion reactors will not be any better from this point of view.
  - 4y ago

smaudet 4y ago

"Still, the NRC and industry consider the leaks a public relations problem, not a public health or accident threat, records and interviews show." https://www.ap.org/press-releases/2012/part-ii-ap-impact-tritium-leaks-found-at-many-nuke-sites#:~:text=Tritium%2C%20which%20is%20a%20radioactive,at%20aging%20nuclear%20power%20plants https://www.ap.org/press-releases/2012/part-ii-ap-impact-tri.... And this is why we should not trust any fission-bearing folk. Or apparently fusion-bearing folk either.

mlindner 4y ago
Tritium leaks are indeed public relations problems, if done in the very small quantities that would be in a fusion reactor.
- pfdietz 4y ago
  > very small quantities that would be in a fusion reactor Fusion reactors would involve much more tritium than in a fission reactor. In the latter, especially LWRs, tritium comes from rare ternary fission events. In a DT fusion reactor, T is a primary fuel. A 1 GWe fusion plant will burn about 150 kg of tritium a year. To illustrate how much that is: that quantity of tritium would be enough to raise 2 months worth of the average flow of the Mississippi River above the legal limit for drinking water.

mlindner 4y ago

> No proliferation risk at all in a tritium fountain full of 14 MeV neutrons? Are you sure you know what you're talking about? If you're putting hunks of uranium inside a fusion pressure vessel it'd be really obvious. Tritium itself doesn't have proliferation risk. > These will all be guarded with pseudo military guns guards and gates just like fission, and monitored by the IAEA. No they won't. Because even if you crash a truck into them there's no ecological disaster. > As for radiological safety, see point about tritium. And google tritium leak nuclear plant for good measure. The tritium stored in the reactor will be in the microgram range. > Youre right that there is less radioactivity in fusion plants, but maybe not enough less to really matter. It's several orders of magnitude less. I think that matters quite a bit.

adrian_b 4y ago
It is completely premature to claim that the radioactivity will be "several orders of magnitude less". The neutron flux produced by a fusion reactor will be much higher than in any fission reactor, and it must be absorbed in a shield, to produce heat, which will be the output of the fission reactor. Choosing an appropriate material for the shield will minimize the quantity of radioactive material that is created per unit of output energy, but it is pretty certain that the radioactivity will not be "several orders of magnitude less". The best that can be hoped is that it is possible to find a shield material that will produce only very small quantities of long-lived radioactive isotopes, so that, after a storage for not too many years, the radioactivity might decrease to be "several orders of magnitude less". Nevertheless this remains to be demonstrated. For example, any piece of steel present near a fusion reactor would produce copious amounts of cobalt 60, but that would decay to negligible radioactivity after a few hundreds years. Moreover, to ensure the predicted low residual radioactivity, any shield material needs to be free of impurities, which even in very small quantities could produce dangerous radioactive isotopes. The requirements for advanced purification will greatly increase the cost of the structural materials for fusion reactors. However this is not a new problem. Similar requirements are imposed on the structural materials for fission reactors, but the fusion reactors will not be any better from this point of view.
- 4y ago