Nuclear Engineering and Design 241 (2011) 3736–3747 Contents lists available at ScienceDirect Nuclear Engineering and Design jo u r n al hom epage : www.elsevier.com/locate/nucengdes Characterization of radiation fields and dose assessment from fuels manufacturing for advanced fuel cycles Benjamin J. Hawkins, Travis W. Knight ∗ Department of Mechanical Engineering, University of South Carolina, Nuclear Engineering Program, 300 Main Street, Columbia, SC 29208, USA a r t i c l e i n f o Article history: Received 2 November 2010 Received in revised form 15 June 2011 Accepted 20 June 2011 a b s t r a c t The purpose of this study was to examine radiological hazards introduced to workers from the fabrica- tion of fuels with minor actinides (MA) and reprocessed uranium (RepU) and determine the feasibility of using shielded gloveboxes instead of remotely controlled operations in hot cells. Of particular concern is the increase in photon source term from the daughter products in RepU and the mixed neutron and photon fields introduced by MA recycle. In the interest of keeping the glovebox worker’s radiation dose as low as reasonable achievable (ALARA), dose rates were calculated for various typical and bounding fuel compositions for light water reactors (LWR) and fast reactor (FR) mixed oxide (MOX) fuels with and without MA. The impact of varying the separation efficiency of americium (Am) and curium (Cm) was examined because current separation processes in reprocessing and recycling do not allow for the complete separation of Am from Cm. The additional Cm will cause a significant increase in the neutron source term. The sensitivity of the fuels to aging time was also examined by decaying the recycled feed- stocks from 6 months to 3 years to simulate the effect of delays in reuse of recycled materials. The highest photon and neutron sources were used to calculate the additional shielding requirements that would be needed for fuel fabrication. Through insight gained from this study, it can be concluded that a standard glovebox with one quarter inch stainless steel walls can be used to fabricate fuels with Am with little to no additional shielding. The introduction of small amounts of Cm in the fuels will require the fuel fabrication to be preformed remotely in hot cells. Thus, stressing the importance of developing methods to increase the separation efficiency of Am from Cm. © 2011 Elsevier B.V. All rights reserved. 1. Introduction 1.1. Motivation Advanced fuel cycles necessitate the development and eval- uation of a number of different processes for handling high transuranic (TRU) content materials to indeed effect an advanced, closed fuel cycle. Some of these processes have yet to be demon- strated or evaluated for the unique considerations imposed by high TRU content materials such as high decay heat, high spe- cific activity, criticality safety, etc. Special consideration is also required due to restrictions imposed by concerns over proliferation. New processes must be evaluated to accommodate homogenous recycling of actinides or some limited form of heterogeneous recy- cling. Studies carried out recently show that multi-pass full-core MOX appears to be a less effective way than multi-pass blended core with ∗ Corresponding author. Tel.: +1 803 777 1465; fax: +1 803 777 0106. E-mail addresses: hawkinb2@email.sc.edu, shai hulud79@yahoo.com (B.J. Hawkins), KNIGHTTW@cec.sc.edu (T.W. Knight). inert matrix fuel to manage the fuel cycle system because it requires higher TRU throughput while accruing waste management bene- fits at a slower rate (Piet et al., 2006). GEN IV reactors such as the high-temperature gas-cooled reactor (HTGR) and fast reactors have certain advantage in Advanced Fuel Cycle Initiative (AFCI) program. The HTGR is a promising system for the incineration of plutonium and possibly minor actinides (Kuijper et al., 2006). The fast reac- tors in a closed fuel cycle can also effectively reduce the amount of spent fuel accumulation and the inventory of the transuranic ele- ments compared to once-through cycles (Jeong and Ko, 2008; Foley and Knight, 2008). Fabrication of fuels from reprocessed materials presents some additional concerns over fabrication from natural uranium and even over concerns associated with plutonium in say MOX fuels (Foley and Knight, 2008; NEA, 2007). While the bulk of spent LWR fuel is uranium it does contain small quantities of 232 U which decays to 208 Tl which emits a high energy photon of 2.6 MeV and can be problematic for shielding. Also included in fuels for an advanced breeder reactor (ABR) would be TRU including minor actinides such as americium and curium. Americium recycle leads to additional production of curium and its recycle is required if larger than a tenfold reduction in radiotoxicity is to be achieved. 0029-5493/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.nucengdes.2011.06.048