Gas emission from the UO2samples, containing fission products and burnable absorber

Depletion of RBMK-1500 spent nuclear fuel (SNF) with and without an erbium burnable absorber was modelled, and one-group burn-up dependent cross-section libraries for Origen-ARP were created. Depletion calculations for the generation of cross-section libraries were performed using the SCALE 6.1 code package with the TRITON control module, which employs the NEWT deterministic 2D transport code with the 238-group energy library based on the ENDF-B VII library and the ORIGEN-S nuclide composition calculation code. Concentrations of the most important actinides for criticality safety were calculated using the created libraries and were compared with the available experimental data and the newest modelling results. Available experimental data of fission products (Nd and Cs isotopes) were also compared to the modelling results. Composition differences were evaluated for several fuel enrichments and water densities. The comparison shows an acceptable agreement between the values obtained using new one-group cross-section libraries and experimental data except for238Pu and241Am, as well as the causes of discrepancy are discussed. It has been found that the enrichment and presence of the burnable absorber play an important role in the SNF composition. At the highest evaluated burn-up (29 GWd/tU) isotopic composition differences between 2% enrichment fuel and 2.8% burn-up for actinides important to burn-up credit (BUC) applications varied from 11 to 52%.

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FUEL BURN-UP DISTRIBUTION AND TRANSURANIC NUCLIDE CONTENTS PRODUCED AT THE FIRST CYCLE OPERATION OF AP1000

JURNAL TEKNOLOGI REAKTOR NUKLIR TRI DASA MEGA ◽

10.17146/tdm.2016.18.2.2665 ◽

2016 ◽

Vol 18 (2) ◽

pp. 101 ◽

Cited By ~ 1

Author(s):

Jati Susilo ◽

Jupiter Sitorus Pane

Keyword(s):

Fuel Assembly ◽

Input Data ◽

Reactor Core ◽

Fission Products ◽

Life Time ◽

Fuel Loading ◽

The Core ◽

Fuel Burn ◽

Burnable Absorber ◽

High Level

ABSTRACT FUEL BURN-UP DISTRIBUTION AND TRANSURANIC NUCLIDE CONTENTS PRODUCED AT THE FIRST CYCLE OPERATION OF AP1000. AP1000 reactor core was designed with nominal power of 1154 MWe (3415 MWth), operated within life time of 60 years and cycle length of 18 months. For the first cycle, the AP1000 core uses three kinds of UO2 enrichment, they are 2.35 w/o, 3.40 w/o and 4.45 w/o. Absorber materials such as ZrB2, Pyrex and Boron solution are used to compensate the excess reactivity at the beginning of cycle. In the core, U-235 fuels are burned by fission reaction and produce energy, fission products and new neutron. Because of the U-238 neutron absoption reaction, the high level radioactive waste of heavy nuclide transuranic such as Pu, Am, Cm and Np are also generated. They have a very long half life. The purpose of this study is to evaluate the result of fuel burn-up distribution and heavy nuclide transuranic contents produced by AP1000 at the end of first cycle operation (EOFC). Calculation of ¼ part of the AP1000 core in the 2 dimensional model has been done using SRAC2006 code with the module of COREBN/HIST. The input data called the table of macroscopic crossection, is calculated using module of PIJ. The result shows that the maximum fuel assembly (FA) burn-up is 27.04 GWD/MTU, that is still lower than allowed maximum burn-up of 62 GWD/MTU. Fuel loading position at the center/middle of the core will produce bigger burn-up and transuranic nuclide than one at the edges the of the core. The use of IFBA fuel just give a small effect to lessen the fuel burn-up and transuranic nuclide production. Keywords: Fuel Burn-Up, Transuranic, AP1000, EOC, SRAC2006 ABSTRAK DISTRIBUSI BURN-UP DAN KANDUNGAN NUKLIDA TRANSURANIUM YANG DIHASILKAN BAHAN BAKAR PADA SIKLUS OPERASI PERTAMA TERAS AP1000. Reaktor AP1000 didesain dengan daya nominal 1154 MWe (3415 MWth), mampu beroperasi selama umur reaktor sekitar 60 tahun dan memiliki panjang tiap siklus sekitar 18 bulan. Pada siklus operasi pertama, teras AP1000 menggunakan tiga jenis pengkayaan bahan bakar UO2 yaitu 2,35 w/o, 3,40 w/o dan 4,450 w/o. Penyerap neutron ZrB2, Pyrex dan larutan Boron digunakan sebagai kompensasi reaktivitas lebih pada awal siklus. Di dalam teras reaktor, bahan bakar U-235 mengalami pembakaran melalui reaksi fisi yang akan menghasilkan energi, produk fisi dan neutron baru. Karena adanya reaksi serapan neutron oleh U-238 maka reaktor juga menghasilkan limbah radioaktif tingkat tinggi berupa nuklida transuranium yang mempunyai waktu paruh sangat panjang seperti Np, Pu, Am, dan Cm. Dalam penelitian ini dilakukan analisis hasil perhitungan distribusi burn-up bahan bakar dan kandungan nuklida transuranium yang dihasilkan oleh teras AP1000 saat akhir siklus operasi pertama. Perhitungan model geometri 2 dimensi teras AP1000 bentuk ¼ bagian dilakukan dengan paket program SRAC2006 modul COREBN/HIST. Sedangkan input data berupa tabel tampang lintang makroskopik diperoleh dari perhitungan dengan modul PIJ. Hasil prhitungan menunjukkan bahwa burn-up perangkat bahan bakar (Fuel Assembly, FA) tertinggi adalah sebesar 27,04 GWD/MTU dan ini masih jauh lebih rendah dari batas maksimum burn-up yang diijinkan yaitu 62 GWd/MTU. Posisi pemuatan perangkat bahan bakar di bagian tengah teras akan menghasilkan burn-up dan nuklida transuranium yang lebih besar dibandingkan dengan ditepi teras. Penggunaan bahan bakar Integrated Fuel Burnable Absorber hanya sedikit berpengaruh terhadap penurunan burn-up dan nuklida transuranium yang dihasilkan. Kata kunci: Fuel burn-up, kandungan nuklida transuranium, AP1000, siklus operasi pertama, SRAC2006

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Nuclear Processes Related to the Ap Stars and the Heaviest Chemical Elements

International Astronomical Union Colloquium ◽

10.1017/s0252921100080520 ◽

1976 ◽

Vol 32 ◽

pp. 169-182

Author(s):

B. Kuchowicz

Keyword(s):

Nuclear Physics ◽

Nuclear Reactions ◽

Chemical Elements ◽

Fission Products ◽

Abundance Pattern ◽

Isotopic Shifts ◽

Processed Material ◽

R Process ◽

Ap Stars ◽

Nuclear Processes

SummaryIsotopic shifts in the lines of the heavy elements in Ap stars, and the characteristic abundance pattern of these elements point to the fact that we are observing mainly the products of rapid neutron capture. The peculiar A stars may be treated as the show windows for the products of a recent r-process in their neighbourhood. This process can be located either in Supernovae exploding in a binary system in which the present Ap stars were secondaries, or in Supernovae exploding in young clusters. Secondary processes, e.g. spontaneous fission or nuclear reactions with highly abundant fission products, may occur further with the r-processed material in the surface of the Ap stars. The role of these stars to the theory of nucleosynthesis and to nuclear physics is emphasized.

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Irradiation behavior of pyrolytic silicon carbide

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074288 ◽

1983 ◽

Vol 41 ◽

pp. 72-73

Author(s):

R. J. Lauf

Keyword(s):

Silicon Carbide ◽

Fission Products ◽

Thermodynamics And Kinetics ◽

Neutron Fluences ◽

Fuel Particles ◽

Sic Coatings ◽

Irradiation Behavior ◽

Kinetics Of ◽

Htgr Fuel

Fuel particles for the High-Temperature Gas-Cooled Reactor (HTGR) contain a layer of pyrolytic silicon carbide to act as a miniature pressure vessel and primary fission product barrier. Optimization of the SiC with respect to fuel performance involves four areas of study: (a) characterization of as-deposited SiC coatings; (b) thermodynamics and kinetics of chemical reactions between SiC and fission products; (c) irradiation behavior of SiC in the absence of fission products; and (d) combined effects of irradiation and fission products. This paper reports the behavior of SiC deposited on inert microspheres and irradiated to fast neutron fluences typical of HTGR fuel at end-of-life.

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TEM studies of amorphization processes and amorphous structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104303 ◽

1988 ◽

Vol 46 ◽

pp. 448-449

Author(s):

T. E. Mitchell ◽

R. B. Schwarz

Keyword(s):

Amorphous Materials ◽

Fission Products ◽

Rapid Quenching ◽

Surface Films ◽

List Type ◽

Oxide Glasses ◽

Crystalline Materials ◽

Amorphous Structures ◽

Amorphous Surface ◽

Interfacial Films

Traditional oxide glasses occur naturally as obsidian and can be made easily by suitable cooling histories. In the past 30 years, a variety of techniques have been discovered which amorphize normally crystalline materials such as metals. These include [1-3]:Rapid quenching from the vapor phase.Rapid quenching from the liquid phase.Electrodeposition of certain alloys, e.g. Fe-P.Oxidation of crystals to produce amorphous surface oxide layers.Interdiffusion of two pure crystalline metals.Hydrogen-induced vitrification of an intermetal1ic.Mechanical alloying and ball-milling of intermetal lie compounds.Irradiation processes of all kinds using ions, electrons, neutrons, and fission products.We offer here some general comments on the use of TEM to study these materials and give some particular examples of such studies.Thin specimens can be prepared from bulk homogeneous materials in the usual way. Most often, however, amorphous materials are in the form of surface films or interfacial films with different chemistry from the substrates.

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