[en] A fuel rod is positioned in axial alignment with a stationary set of cutters on a table and a winch on the other end of the table pulls the rod through the cutters and in so doing, cuts a groove almost through the opposite sides of the rod. As the machine continues pulling the rod, it is caused to spread open and drop fuel rod pellets into a receptacle for later disposition. (Patent Office Record)

[en] To organize data being obtained in an existing experimental program on the dispersion coefficient for material in a rotating kiln, a dimensional analysis was performed using all of the variables now thought to be relevant. Rotary kilns are being considered for use in the voloxidation process for the recovery of tritium from spent nuclear power reactor fuels. Design for the efficient recovery of tritium stipulates a residence time distribution for material within the kiln; therefore, a consideration of material dispersion is important. The study revealed that the system is fairly tightly constrained. Of all possible dimensionless groups formed from the process variables, only three remained after those groups consisting of ratios of length were extracted and allowance was made for implicit relations among variables. The set that describes the system includes the velocity number, the Watt number, and the fraction of the kiln filled with solids. Since the velocity number divided by the operating slope of the kiln behaves as a constant (at least for first-order effects), the program should correlate the Watt number with fraction full and the dimensionless numbers that relate the geometry of the system, including size of the feed material and flight dimensions

[en] Design of an engineering-scale trapping system to be used in PRIDE (Pyroprocess Integrated Inactive Demonstration) facility of KAERI to remove semi-volatile fission gases generated from the advanced vololoxdation process of 50 kg-SF/batch was performed. The design was performed to produce flow diagram for the off-gas trapping system. The gaseous waste arisings for off-gas trapping system was estimated considering the release rate of each target fission product. To design the off-gas trapping system, zero release concept was taken to the environment through off-gas trapping system. Each unit process in the trapping system is arranged to effectively remove the species of interest by considering the chemical properties of the target fission products to be trapped. Cs and Rb are trapped on a fly ash filter at around 900 .deg. C. Tc, Te, Se, and Mo on a calcium filter are trapped at about 700 .deg. C, and I on a AgX is trapped at about 250 .deg. C. Off-gas trapping system was designed based on the design requirements such as trapping media, fission products to be trapped, design temperatures of the trapping units, optimum operation temperatures and specifications of the filters. Off-gas trapping system was also designed based on the design requirements such as reomoteability, accessibility, operationability and flexibility of instrument, separability of trapping basket, material of instrument

[en] The selection of mechanical dismantling and cutting methods instead of thermal cutting by grinding, for example, is a decision taken for reasons of radiological safety, in order to prevent entrainment of radioactivity. Radiological protection is one of the main reasons leading to application of mechanical methods for dismantling, as the thermal dismantling and thermal grinding methods produce dust and other debris that are a hazard to the personnel, not only due to the radioactivity. Mechanical dismantling work does not require protective means such as tents, hoods, or the like. (orig./DG)

[en] Full text of publication follows: ORNL is conducting a complete, coupled end-to-end (CETE) demonstration of advanced nuclear fuel reprocessing to support the Global Nuclear Energy Partnership (GNEP). These small scale reprocessing operations provide a unique opportunity to test integrated off-gas treatment systems designed to recover the primary volatile fission and activation products (³H, ¹⁴C, ⁸⁵Kr, and ¹²⁹I) released from the spent nuclear fuel (SNF). The CETE project will demonstrate an advanced head-end process referred to as 'Voloxidation' designed to condition the spent nuclear fuel, separate the SNF from the cladding, and release of tritium contained in the fuel matrix. The off-gas from this process as well as from the more traditional fuel dissolution process will be treated separately and the volatile components recovered. This paper will provide descriptions of the off-gas treatment systems for both the Voloxidation process and for the fuel dissolution process, and provide preliminary results from the initial CETE processing runs. Impacts of processing parameters on the relative quantities of volatile components released and recovery efficiencies will be evaluated. (authors)

[en] For reprocessing spent fuel elements are cut by series of 3 to 8 offset blades, distance between edges of parallelepipedic blades is equal to the thickness of the fuel element bundle

[en] After separation of the top piece and bottom piece, the spacer grid devices are progressively separated in layers from fuel rod level to fuel to fuel rod level and are removed from the fuel rods. The released fuel rods are then taken from the fuel element in layers and are placed in a more compact configuration. A separating tool with a separating disc head is used for separation. The release of the fuel rods is done using pliers, which bend the separated spacer grid open in steps. (orig./HP)

[en] This invention concerns an apparatus and process for recovering fuel pellets from nuclear fuel elements containing them. The main object of the invention is to provide a simple apparatus for easily removing fuel pellets from their cladding without damaging them. An opening is created in one end of the fuel element, a liquid at high pressure is introduced into the cladding by this aperture in order to place the fuel element under pressure and bring about the expansion of the metal cladding to clear the fuel pellets it contains. This cladding is then cut up to allow the fuel pellets to slide from the cladding

[en] The objective of this report is to develop the trapping concepts for immobilizing the volatiles from voloxidation process. KAERI supplied fly ash filters for cesium, calcium filters for ruthenium and technetium, and AgX for I to INL. Based on KAERI's experimental results and experience on the trapping characteristics of each gaseous fission product in terms of carrier gas and chemical species, INL hot experiments will be performed in off-gas treatment system (OTS) for a voloxidizer. This report will be used as useful means for providing the trapping methods for trapping semi-volatile fission products under air, oxygen, and vacuum conditions. As results of trapping experiments, it was found that trapping efficiency of cesium volatilized from CsI by fly ash filter was decreased in the order of Air> Ar > O₂ > vacuum conditions. It was also found that higher trapping temperature, close to 1100 .deg. C, tends to give an improved trapping efficiency even at vacuum condition

[en] The head-end process plays an important role in providing feed materials to electrolytic reduction after fabrication of the fuel fragments (crushed pellets) and the porous pellets feed materials. The head-end process is composed of various devices such as disassembling/rod extraction/rod cutting devices of the nuclear fuel assembly, oxidative decladding device, compaction, and pre-treatment device. The head-end process project currently has no hotcell. In addition, there are no tools validate core devices designed or manufactured. This paper introduces a head-end process fDMU (Functional DMU) being developed to solve this problem. To establish the efficiency and reliability of core devices based on a previous DMU environment, an advanced fDMU for the head-end process was designed. It was concluded that fDMU has great features such as a functional integration and validation of virtual mechatronic systems, couple the functional and geometry models within the total system model, and combine the functional simulation and interactive 3D visualization