Flowsheet testing

Law, J.D., Herbst, R.S., Todd, T.A. 2002. Integrated AMP-PAN, TRUEX, and SREX testing. II. Flowsheet testing for separation of radionuclides from actual acidic radioactive waste. Sep. Sci. Technol. 37 (6) 1353-1373. 

Herbst, R.S., Law, J.D., Todd, T.A. et al. 2002. Universal solvent extraction (UNEX) flowsheet testing for the removal of cesium, strontium, and actinides elements from radioactive, acidic dissolved waste. Solvent Extr. IonExch. 20 (4—5) 429 445. 

FIGURE 3.10 DIAMEX process flowsheet tested at the CEA Marcoule in 2000 with DMDOHEMA. (Courtesy of Madic, C., Lecomte, M., Baron, P., Boullis, B., Compte-Rendu de Physique, 3, 797-811, 2002.)... 

As organic and aqueous phases are macroscopically separated by the membrane, HFM offer several hydrodynamic advantages over other contactors, such as the absence of flooding and entrainment, or the reduction of feed consumption (160, 161). The flowsheets tested in HFM were similar to those developed for centrifugal contactor tests. Computer codes based on equilibrium (162) and kinetics data, diffusion coefficients (in both phases and in the membrane pores), and a hydrodynamic description of the module, were established to calculate transient and steady-state effluent concentrations. It was demonstrated that, by selecting appropriate flow rates (as mass transfer is mainly controlled by diffusion), very high DFs (DI A 11 = 20,000 and DFrm = 830) could be achieved. Am(III) and Cm(III) back-extraction efficiency was up to 99.87%. 

Thanks to these promising results, two hot tests were further carried out in the hot cells of the ITU (181, 182) on a genuine highly active PUREX raffinate obtained by reprocessing 500 g of a U02 commercial reactor spent fuel (60 GWd/t). Oxalic acid and HEDTA were added to the PUREX high-activity raffinates, and its acidity was adjusted to 4.4 M. The flowsheet tested was... 

FIGURE3.14 TODG A/TBP process flowsheet tested at the FZ J on a surrogate PUREX raffinate. (Courtesy of Modolo, G., Asp, H., Vijgen, H., Malmbeck, R., Magnusson, D., Sorel, C., Global 2007 Advanced Nuclear Fuel Cycles and Systems, September 2007, Boise, ID.)... 

FIGURE 3.23 ALINA process flowsheet tested at the FZJ on a surrogate DIAMEX product. (Courtesy of Modolo, G., Odoj, R., Baron, P., Global 1999 Nuclear Technology - Bridging the Millennia, August-September 1999, Jackson Hole, WY.)... 

FIGURE 3.24 SETFICS process flowsheet tested by JNC on an inactive surrogate PUREX raffinate. (Courtesy of Hirano, H., Koma, K., Koyama, T., 7th Information Exchange Meeting on Actinide and Fission Product Partitioning and Transmutation, October 2002, Jeju, Republic of Korea.)... 

FIGURE 3.25 SETFICS process flowsheet tested at JAEA (CPF) on a highly active feed. (Courtesy of Nakahara, M., Sano, Y., Koma, Y., Kamiya, M., Shibata, A., Koizumi, T., Koyama, T. 2007. Journal of Nuclear Science and Technology, 44, 373-381, 2007.)... 

While this chapter and this applications section has focused on ANL and CINC contactors, other centrifugal contactors have been used to process nuclear materials. Some of these contactors and the flowsheets tested using them are discussed here. 

Law, J. D., R. S. Herbst, T. A. Todd, et al. 2001. Flowsheet Testing of the Universal Solvent Extraction Process for the Simultaneous Separation of Cesium, Strontium, and the Actinides from Dissolved INEEL Calcine. Proceedings of WM-01, February 25-March 1, 2001, Tucson, AZ. 

Leonard, R. A., S. B. Aase, H. A. Arafat, et al. 2002a. Simulant Flowsheet Test with Modified Solvent for Cesium Removal Using Caustic-side Solvent Extraction. Argonne National Laboratory Report ANL-02/22, Argonne, IL. 

In addition to collection of comprehensive distribution data, Schulz s investigations embraced ways of purifying commercial-grade DHDECMP, alpha radiolysis of DHDECMP-CCI4 solvents, and mixer-settler flowsheet tests with both synthetic and actual CAW solutions. Collectively, results of this research clearly demonstrated the many advantages of substituting DHDECMP for DBBP. Shutdown of PRF Am(III) extraction operation in 1976 prevented follow-on plant tests of the DHDECMP flowsheet. 

Flowsheet testing and data collection were performed using the General Atomic Company solvent extraction pilot plant equipment shown in Figure 1. Included in this equipment are several 5.1 to 7.6 cm (2 to 3 in.) diameter cylindrical glass pulse columns, a 15-2 cm (6 in.) diameter annular pulse column, a centrifugal contactor (Robatel Co.) and associated tanks, feed systems and concentrators. 

Flowsheet Testing. Na2C03 scrub waste solutions were prepared by extracting measured amounts of U(VI) and Pu(IV) into dodecane solutions containing 0.02 M - 0.04 M HDBP and 0.0067 M -0.0134 M H2MBP. The resultant organic phase plus precipitates were then slurried with the required amount of Na2C03 until all the precipitate dissolved. 

Law, J. 1998. Countercurrent flowsheet testing of the TRUEX process with ICPP calcine. Proceedings of the International Conference on Decommissioning and Decontamination and on Nuclear and Hazardous Waste management, 566-70, Denver, CO, September 13-18. 

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