LMFBR program

Figure 3. Concentration ratios (CR) for Pu and Am. CR is defined as the simple ratio of actinide concentration for plants vs. soil on a dry weight basis. Sites where data sets have been collected are NTS (Nevada Test Site, Nev.), SR (Savannah River, S. C.), OR (Oak Ridge, Tenn.), RF (Rocky Flats, Col.), Enewetak Atoll, South Pacific. Arrow denotes approximate value used in the LMFBR Program Impact Assessment (2).

A.88oelated with the development of Liquid-Metal Fhst Breeder Reactors will be the need to fabricate, process, and recover larp quantities of mixed PuCh-UQi fuels. There is, however, a lack of homogeneous experimental criticality data that can be used to provide guidance for establishing nuclear criticality safety specifications for fuels typical of those to be encountered in the LMFBR program. Consequently, one must resort to computed values for guidance. ... 

ZPPR is designed to be used for physics studies of power breeder reactor systems in support of the AEC s lMFBR program, and can accommodate mockups characr terlstic of the proposed 300- to 500-MW(e) demonstration pltmts and lOOO-MW(e) commercial plants- Compositiph simulation is accomplished by assembling fuel, coolant, and structural materials, In the form of small plates, Into drawers which are, In turn, loaded into the reactor matrix. 

Although the data have been generated in support of the LMFBR program, the experimental results on the 7.89 wt% Pu-enriched fuel will be of use to the li t-water reactor community. The plutonium enrichment range applicable to the LWR fuels is between 3 and 8 wt%, but experimental criticality data on homogeneous mixtures have been unavailable for these low enrichment systems. 

Aqueous Processing of LMFBR Fuels, Technical Assessment and Experimental Program" ORNL-4436, June 1970. 

G9. Goode, J. H., and S. D. Clinton Aqueous Processing of LMFBR Fuels—Technical Assessment and Experimental Program Definition, Report ORNL-4436, secs. 4.4 and... 

Seismic analysis method development and verification on FBR core in the framework of "lAEA/IWGFR Coordinated Research Program on Intercomparison of LMFBR Seismic Analysis Codes" was completed in 1995. From 1996 PNC joins SYMPHONY program on FBR core seismic tests and analysis at CEA, France. 

ZPPR Assembly 2 is part of the demonstration reactor benchmark critical assembly program. E is a Ihrge, zoned, critical assembly designed to simulate the compositions and configurations of the LMFBR demonstratioh> plants. 

LMFBR Demonstration Reactor Benchmark Critical Experiments Program—Initiol P iate-Rod Heterogeneity Measurements, R. A. 

An initial set of measurements has been carried out to evaluate the effect on measured core physics parameters of the configurationai heterogeneity differences between the nornial pbte-form ZPR fast critical assemblies and rodded assemblies typical of a Pua-PuOa-fueled LMFBR. These measurements are the first set of a series of heterogeneity measurements planned for the ANL LMFBR Demonstration Plant Critical Experiments Program currently underway on ZPR-6 (Assembly 7) and ZPPR (Assemblies 2 and 3). 

Soluable poisons for secondary protection. Generally satisfied for LMFBR fuel compositions by Hanford data, for water-reactor fuel by Y-12 program, if limited to backup protection. But see item 3. 

C. E. TILL et al., ZPR-6 Assemblies 6A and 7 Benchmark S ciGcation for the Two Large Single-Core-Zone Critical Assemblies— U-Fueled Assembly 6A and Phitonium-Ftaeled Assembly 7—LMFBR Demonstration Reactor Critical Experiment Program, Applied Physics Division Annual Report, July 1, 1970 to June 30, 1971, ANL-7910, pp. 86-102. Argonne National Lab. 

Nonetheless, the experimental criticality data cur> rently available for LMFBR fuels do provide a secure validation point for (Pu, U)C>2 fuels to be used in the fast flux test facility (FFTF) program. Indeed, the data in Table H were obtained for this program. As a consequence, the criticality safety parameters for FFTF fuel pin handling are currently based directly on the experimental data, since the fuel rods used in the experiments are nearly the same sizes as those to be used in the FFTF reactor. These criticality parameters are as follows ... 

When the configuration of the next-generation LMFBR is known better, results from this program of critical experiments will permit initial assessment of phytics feasibility, and will guide planning for experiments on more prototypic configurations ... 

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