用過核燃料中的次要錒系元素是造成放射性廢料擁有長期危害的主要原因。本論文利用再循環次要錒系元素的核燃料循環，探討次要錒系元素的減量效果，並採用SCALE計算程式系統中的SAS2H控制模組，模擬燃料在燃燒和冷卻過程中核種隨時間的變化。本論文分別針對輕水式反應爐和液金快滋生反應爐的核燃料循環作計算，並參考文獻資料建立兩種反應爐的計算模型。
輕水式反應爐使用氧化鈾作燃料，235U的濃化度是 3.2%，燃耗設定在 33 GWD/tHM。液金快滋生反應爐使用混合耗乏鈾和鈽的氧化燃料， 其中鈽是由輕水式反應爐中的用過核燃料提煉製成，耗乏鈾和鈽重量各佔 87.6% 和 12.4%，設定燃耗為 100 GWD/tHM。在經歷完整燃燒和冷卻過程之後，用過核燃料中的次要錒系元素再加到新的燃料中，然後儲存一段時間再放進反應爐中燃燒。核燃料循環中的冷卻和儲存時間的總和，在輕水式反應爐中是五年；而在液金快滋生反應爐中是十年。
結果顯示輕水式反應爐封閉核燃料循環跟一次核燃料循環相比，在第十次循環時，次要錒系元素總量減少達到 20%。在液金快滋生反應爐核燃料循環中，經過二十次再循環次要錒系元素，可使次要錒系元素總量減量高達 90%。由於次要錒系元素為高放射性的元素，基於輻射安全的考量，針對再循環之新燃料的射源強度和等效劑量率作評估。在幾次循環後，新燃料的射源強度約維持在同一個水平，每根燃料的中子射源強度約為 3.3×108 neutrons/s，光子射源強度約為 2.3×1013 gamma-rays/s；而在距離射源1米處，中子和光子等效劑量率分別為 3.8×103 µSv/hr 和 8.4×104 µSv/hr 。因此，在新燃料製造、運輸和吊裝上的屏蔽問題必須額外加以考慮。

The minor actinides in spent fuels dominate long-term hazard radioactive waste. In this study, we evaluated the minor actinides reduction in minor actinides multiple recycling fuel cycle compared with minor actinides non-recycling. SAS2H control module in SCALE 4.4a code system was used to calculate fuel depletion and actinide transmutation. The LWR and LMFBR fuel cycle were investigated respectively.
For the LWR fuel cycle it was assumed that the fresh fuel consists of uranium oxide with a 3.2% enrichment of 235U and the burnup is 33 GWd/tHM. For the LMFBR fuel cycle the fresh fuel was assumed to be the oxide fuel consisting of 12.4% of Pu, which is from thirteen of the LWR spent fuels, and 87.6% depleted uranium and a burnup of 100 GWd/tHM was adopted. After the completion of the burnup and cooling, the minor actinides in the spent fuel were added in the fresh fuel and stored a while for recycling. It was assumed that the sum of cooling time and storage time are 5 years for LWR and 10 years for LMFBR.
For LWR, the minor actinides reduction in multiple recycling fuel cycle at 10th recycling are 20% compared with LWR once-through fuel cycle. For LMFBR the minor actinides reduction in minor actinides multiple recycling fuel cycles at 20th recycling are 90% compared with minor actinides non-recycling fuel cycle. For radiation shielding safety issue, the source intensity and dose equivalent rate of fresh fuels in minor actinides recycling LMFBR fuel cycle were also evaluated. It was found that after a few recycling the neutron intensity of the fresh fuel is ~3.3×108 neutrons/s per assembly and the gamma-ray source intensity is ~2.3×1013 gamma-rays/s per assembly. Furthermore, the neutron and gamma dose equivalent rate at 1 m distance from the fresh fuels are ~3.8×103 µSv/hr and ~8.4×104 µSv/hr, respectively. Therefore, shielding problems must be taken into account for fuel fabrication, transportation, and handling.

Chinese Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i
English Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
Acknowledgment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
List of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Problem description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Transmutation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.3 Literature review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.4 Objectives of this thesis . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1 Code description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1.1 SCALE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1.2 SAS2H . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.1.3 ORIGEN-S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.1.4 SCALE Cross Section Libraries . . . . . . . . . . . . . . . . . . . 12
2.1.5 BONAMI and NITAWL-II . . . . . . . . . . . . . . . . . . . . . . 15
2.1.6 XSDRNPM-S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2.1.7 COUPLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
2.2 LWR calculation model setup . . . . . . . . . . . . . . . . . . . . . . . . 24
2.3 LMFBR calculation model setup . . . . . . . . . . . . . . . . . . . . . . 25
2.4 Radiotoxicity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
3 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
3.1 Minor actinides production in LWR once-through fuel cycle . . . . . . . . 29
3.1.1 The amount and radiotoxicity of nuclides in the LWR spent fuels 29
3.1.2 Minor actinides production in the LWR spent fuels with different
burnups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3.2 Minor actinides incineration in multiple recycling LWR fuel cycles . . . . 32
3.2.1 The scheme of minor actinides recycling LWR fuel cycles . . . . . 32
3.2.2 Minor actinides reduction in multiple recycling LWR fuel cycles . 33
3.3 Minor actinides production at the first LMFBR fuel cycle . . . . . . . . . 36
3.4 Minor actinides incineration in multiple recycling LMFBR fuel cycles . . 38
3.4.1 The scheme of multiple recycling LMFBR fuel cycles . . . . . . . 38
3.4.2 Minor actinides reduction in the multiple recycling LMFBR fuel
cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
3.4.3 The neutron and gamma-ray source strengths of the fresh and spent
fuels in multiple recycling LMFBR fuel cycles . . . . . . . . . . . 44
4 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . 48
5 Future work . . . . . . . . . . . . . . . . . . . . . . . . 50
References. . . . . . . . . . . . . . . . . . . . . . . . 51
Appendix . . . . . . . . . . . . . . . . . . . . . . . . 53
A The resonance data of 238U in the 44GROUPNDF5 cross-section library . . . 53
A.1 Bondarenko Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
A.2 NITAWL-II Resonance Data . . . . . . . . . . . . . . . . . . . . . . . . . 55
B SAS2H Input Files. . . . . . . . . . . . . . . . . . . . . . . . 61
B.1 PWR 33 GWd/tHM at the first LWR fuel cycle . . . . . . . . . . . . . . 61
B.2 LMFBR 100 GWd/tHM at the first LMFBR fuel cycle . . . . . . . . . . 63
C Ingesting Dose Coefficients . . . . . . . . . .67

[1] F. Varaine, A. Zaetta, D. Warin, and M. Delpech. Review on Transmutation Studies
at CEA: Scientific Feasibility According Neutronic Spectrum. Proceedings of
GLOBAL 2005, Tsukuba, Japan, October 2005.
[2] C.H.M. Broeders, E. Kiefaber, and H.W. Wiese. Burning Transuranium Isotopes in
Thermal and Fast Reactors. Nuclear Engineering and Design, 202:157–172, 2000.
[3] K.S. Allen and E.P. Naessens. Monte Carlo-Based Analysis for the Transmutation of
Transuranic Waste Recycled in Light Water Reactors. Nuclear Technology, 152:354–
366, 2005.
[4] E.L. Gluekler. U.S. Advanced Liquid Metal Reactor(ALMR). Progress in Nuclear
Energy, 31(12):43–61, 1997.
[5] N. Messaoudi and J. Tommasi. Fast Burner Reactore Devoted to Minor Actinide
Incineration. Nuclear Technology, 137:84–96, 2001.
[6] I. Krivitski, M. Vorotyntsev, V. Pyshin, and L. Korobeinikova. Safety Analysis of
Fast Reactor Core with Uranium-Free Fuel for Actinide Transmutation. Nuclear
Technology, 143:281–289, 2003.
[7] O. W. Hermann and K. D. Dobbin. SAS2H: A Coupled One-Dimensional Depletion
and Shielding Anaylsis Module, March 2000.
[8] O. W. Hermann and R. M. Westfall. ORIGEN-S: SCALE System Module to Calculate
Fuel Depletion Actinide Transmutation, Fission Product Buildup and Decay,
and Associated Radiation Source Terms, 2000.
[9] N.M. Greene. BONAMI: Resonance Self-Shielding by the Bondarenko Method. Oak
Ridge Natl. Lab., March 2000.
[10] N.M. Greene, L.M. Petrie, and R.M. Westfall. NITAWL-II: Scale System Module for
Performing Resonance Shielding and Working Library Production. Oak Ridge Natl.
Lab., March 2000.
[11] N.M. Greene and L.M. Petrie. XSDRNPM: A One-Dimensional Discrete-Ordinates
Code for Transport Analysis. Oak Ridge Natl. Lab., March 2000.
[12] O. W. Hermann. COUPLE: SCALE System Module to Process Problem-Dependent
Cross Sections and Neutron Spectral Data for ORIGEN-S Analysis. Oak Ridge Natl.
Lab., March 2000.
[13] D.R. Kingdon, V.A. Khotylev, and A.A. Harms. Conceivable Limits for Thermal
Reactor Spent-Fuel Recycling. Nuclear Technology, 127(2):186–198, August 1999.
[14] H.W. Wiese. Actinide Transmutation Properties of Thermal and Fast Fission Reactors
Including Multiple Recycling. Journal of Alloys and Compounds, p. 522–529,
1998.
[15] S. M. Bowman and L. C. Leal. ORIGEN-ARP: Automatic Rapid Process For Spent
Fuel Depletion, Decay, and Source Term Analysis, March 2000.
[16] J.J. Duderstadt and L.J. Hamilton. Nuclear Reactor Analysis, p. 634–635. John
Wiley & Sons, Inc., 1976.
[17] International Atomic Energy Agency. Status of Liquid Metal Cooled Fast Breeder
Reactors, chapter VI, p. 311. 1985.
[18] Institute for Transuranium Elements. NUCLIDES 2000 - An Electronic Chart of the
Nuclides on CD, ITU, Joint Research Center, Europian Commision.
[19] J.R. Larmash and A.J. Baratta. Introduction to Nuclear Engineering, p. 519. Third
edition.