Nuclear waste
Nuclear waste may mean spent nuclear fuel, extracted from the nuclear reactors.
Nuclear waste may refer to substances with unstable isotopes, created at manufacturing of the nuclear fuel, or retreatment of the spent nuclear fuel.
Nuclear waste may refer to contamination, released to atmosphere, water and/or soil at the accidents, catastrophes or the criminal uncontrolled management.
In all the three cases, term Nuclear waste refers to some dangerous and usually unwanted substance.
Scale of the disaster
Most of popular news agencies, sites, newspapers mention the problem of nuclear contamination or risks of such a contamination, at least in so-called "popular" form, without numerical estimates and without formulas. In the vulgar interpretation, the problem of the nuclear waste appears as a world-wide disaster. Scale of this «disaster» is discussed in this section.
Usually, the authors, who mention the Nuclear waste, do not imagine even orders of magnitude of the quantities they are writing about; in particular, they they do not provide table of the isotopic content of the nuclear waste. This may indicate some kind of sabotage of personal of the nuclear facilities: they do not estimate even orders of magnitude of amounts of the dangerous substance.
However, there are some exceptions from this general rules. The amount of nuclear waste, produced in Germany, is sedimated [1]
The table of amount of 43 most important unstable isotopes produced in Germany in 2022 is copy pasted here:
| No | isotope | amount,t |
|---|---|---|
| 01 | U-233 | 3.59e-5 |
| 02 | U-234 | 4.50e-1 |
| 03 | U-235 | 8.41e+1 |
| 04 | U-236 | 4.21e+1 |
| 05 | U-237 | 4.79e-7 |
| 06 | U-238 | 9.58e+3 |
| 07 | Pu-238 | 3.05e+0 |
| 08 | Pu-239 | 7.10e+0 |
| 09 | Pu-240 | 3.66e+1 |
| 10 | Pu-241 | 9.91e+0 |
| 11 | Pu-242 | 1.01e+1 |
| 12 | Pu-244 | 9.92e-4 |
| 13 | Th-229 | 3.12e-9 |
| 14 | Th-230 | 1.30e-5 |
| 15 | Th-232 | 1.98e-5 |
| 16 | Pa-231 | 1.33e-6 |
| 17 | Pa-233 | 2.11e-7 |
| 18 | Np-237 | 6.21e+0 |
| 19 | Np-238 | 4.77e-9 |
| 20 | Np-239 | 2.02e-6 |
| 21 | Am-241 | 1.22e+1 |
| 22 | Am-242 | 3.30e-7 |
| 23 | Am-242m | 2.77e-2 |
| 24 | Am-243 | 2.34e+0 |
| 25 | Cm-242 | 1.16e-3 |
| 26 | Cm-243 | 7.34e-3 |
| 27 | Cm-244 | 5.72e-1 |
| 28 | Cm-245 | 7.43e-2 |
| 29 | Cm-246 | 6.76e-3 |
| 30 | Cm-247 | 9.52e-5 |
| 31 | Cm-248 | 6.56e-6 |
| 32 | Bk-249 | 5.84e-10 |
| 33 | Cf-249 | 9.78e-8 |
| 34 | Cf-250 | 7.51e-9 |
| 35 | Cf-251 | 5.90e-9 |
| 36 | Cf-252 | 5.53e-11 |
| 37 | Cs-134 | 8.74e-2 |
| 38 | Cs-135 | 5.43e+0 |
| 39 | Cs-137 | 1.04e+1 |
| 40 | Sr-90 | 4.29e+0 |
| 41 | Tc-99 | 9.28e+0 |
| 42 | I-129 | 2.27e+0 |
| 43 | Ru-106 | 3.33e-2 |
The table above appeared in year 2013; so, one can guess, that it is one a prediction. Up to date, in the open access, no publication is found to confirm or to reject this estimate. However, one can expect, that since year 2013, the nuclear physics had nor chance, nor the main decision of the nuclear reactors; so, at least orders of macnitude of the quantities suggested may be correct.
Main components
The table indicates that the main components of the nuclear waste are
| 00 | isotope | amount,t | Halflife |
|---|---|---|---|
| 03 | U-235 | 8.41e+1 | |
| 04 | U-236 | 4.21e+1 | |
| 06 | U-238 | 9.58e+3 | |
| 07 | Pu-238 | 3.05e+0 | |
| 08 | Pu-239 | 7.10e+0 | |
| 09 | Pu-240 | 3.66e+1 | |
| 10 | Pu-241 | 9.91e+0 | |
| 11 | Pu-242 | 1.01e+1 | |
| 18 | Np-237 | 6.21e+0 | |
| 21 | Am-241 | 1.22e+1 | |
| 24 | Am-243 | 2.34e+0 | |
| 38 | Cs-135 | 5.43e+0 | |
| 39 | Cs-137 | 1.04e+1 | |
| 40 | Sr-90 | 4.29e+0 | |
| 41 | Tc-99 | 9.28e+0 | |
| 42 | I-129 | 2.27e+0 |
At leas one tonne of each of these isotopes is produced yearly in Germany. Extrapolating, one can guess, that the total amount of the isotopes, produced world-wide during a century, is at least 3 orders of magnitude bigger.
The total amount of these nuclear waste is not so big; it could git a cube of size of order of 20 meters. However, it is would not be a good idea to keep all the nuclear waste in a single compact cube; at least because father relaxation heat.
Namely these isotopes should be taken into account in the estimates of the future of the nuclear energetics, at least in century 21. total amount of the isotopes, produced worldwide during a century shold be at least 3 orders of magnitude larger, than in the table above.
Below, the table above is extended: From Wikipedia (mainly), the masses and lifetimes of the contaminants are loaded:
0 name M,tonn atomic m, amu HalfL,y En,MeV 1 U-235 84 235.04392949 703.8e6 4.9 2 U-236 42 236.045568 2.342e7 4.572 3 U-238 9580 238.05078826 4468.e6 51.77 4 Pu-238 3 238.049553 87.7 5.593 5 Pu-239 7 239.0521634 24110 6 Pu-240 37 240.0538135 6561 7 Pu-241 10 241.057 14 8 Pu-242 10 242.059 375000 9 Np-237 6 237.0481734 2.144e6 10 Am-241 12 241.056829144 432.2 11 Am-243 2 243.0613811 7370 12 Cs-135 5 134.9059770 2.3e6 13 Cs-137 10 136.9070895 30.1671 14 Sr-90 4 89.907738 28.90 15 Tc-99 9 98.906254 211000 16 I-129 2 128.904984 1.57е7 0.189
Trash of useful product?
There is no absolute trash. Existence of any "unwanted" substance indicates, that yet, there is no technology, that would make the separation of the substance to components (that has positive price at the market) is economical non-profitable. In many cases, it is cheaper just to store the waste, than to separate it to components that can be sold.
Am-241
The most important (id let, most dangerous) in the table above seem to be Pu-241 and Am-241.
Estimates, that after a 100 years, namely Am-241 will produce the most of the relaxation heat
Art
Warning
References
- ↑ https://www.hindawi.com/journals/stni/2013/293792/ Research Article | Open Access Volume 2013 |Article ID 293792 | https://doi.org/10.1155/2013/293792 A. Schwenk-Ferrero, "German Spent Nuclear Fuel Legacy: Characteristics and High-Level Waste Management Issues", Science and Technology of Nuclear Installations, vol. 2013, Article ID 293792, 11 pages, 2013. https://doi.org/10.1155/2013/293792
https://pubs.rsc.org/en/content/articlelanding/2022/ja/d2ja00052k Aurélien Beaumais, ORCID logo *a Anthony Nonell,*a Céline Caussignac,a Sébastien Mialle,a Guillaume Stadelmann,b Myriam Janin,c Hélène Isnard,a Michel Aubert,a Thomas Vercouterd and Frédéric Chartiere. Journal of Analytical Atomic Spectrometry. Issue 6, 2022. he low abundance cerium-144 radionuclide is one of the significant contributors to the decay heat from spent nuclear fuel for cooling times of less than ten years after nuclear reactor discharge. The accurate quantification of the 144Ce content (or 144Ce/238U) in irradiated nuclear fuel is necessary to validate and extend the neutronic calculation codes as well as to improve the short-term nuclear waste management strategies. In order to quantify the 144Ce/238U atomic ratios at low uncertainty, we developed a new analytical technique based on double spike isotope dilution associated with mass spectrometry. This includes (1) the chemical elimination of the major neodymium-144 isobaric interference by two steps of liquid chromatography prior to isotope analysis by Thermal Ionization Mass Spectrometry (TIMS) using both total evaporation and sequential methods, and (2) the preparation and use of an in-house double spike solution, using a mixture of a natural Ce solution with a 233U-enriched solution. This new approach was applied for the first time on two Mixed Oxide (MOx) spent nuclear fuel samples and allowed the determination of 144Ce/238U atomic ratios ranging from 35 × 10−6 to 59 × 10−6 with a relative expanded uncertainty of measurement of around 1% at a 95% confidence level.