Waste from high-level liquid

The above information was used to develop conceptual flowsheets for the extraction of all of the actinides (U, Np, Pu, Am, and Cm) from high-level liquid waste from PUREX processing using 0.4 M 0fuel using 0.8 M DHDECMP in DEB. In both flowsheets, no oxidation state of Pu is necessary since the III, IV, and VI state extract into the organic phase. 

Conceptual flowsheet for the extraction of actinides from high-level liquid waste using 0.4 M 0<)>D[IB]CMP0 in DEB. 

Simon, N., Toumois, B., Eymard, S. et al. 2004. Cs selective extraction from high level liquid wastes with crown calixarenes Where are we today Atalante, Nimes, France, June 21-25, pp. 1-57. 

Madic, C., Blanc, P., Condamines, N., Baron, P., Berthon, L., Nicol, C., Pozo, C., Lecomte, M., Philippe, M., Masson, M., Hequet, C., Hudson, M.J. 1994. Actinide partitioning from high level liquid waste using the DIAMEX process. RECOD 94, April, London, UK. 

Hirano, H., Koma, K., Koyama, T. 2002. Waste minimization in actinides(IH)/ lanthanides(III) separation process from high-level liquid waste. 7th Information Exchange Meeting on Actinide and Fission Product Partitioning and Transmutation, October, Jeju, Republic of Korea. 

Chinese scientists used trialkyl phosphine oxides (TRPO) to remove long-lived radioactive nuclides from high-level liquid waste (67, 167). TRPO is the trademark of a Chinese commercial product, consisting of a mixture of several TRPO (with alkyl chains from hexyl to octyl). The TRPO process has been tested in China and at ITU in Karlsruhe (2, 168-174). 

Xuegang, L., Junfu, L., Jingming, X. 2004. Simplified Chinese TRPO Process to extract and recover transuranium elements from high-level liquid waste. Solvent Extr. Ion Exch. 22(2) 163-173. 

Figure 1. Batch cross current extraction of Am-Cm from high-level liquid waste with 30% DHDECMP 3M HNOs 25°C organic-to-aqueous phase ratio = L...

In addition, Na2C03 scrub waste will be generated in the clean-up of the dihexyl-N,N-diethyl carbamoylmethylene phosphonate (DHDECMP) extractant which is to be used to extract all of the actinides from high-level liquid waste (HLLW) in the proposed waste treatment facility described by Tedder, Finney, and Blomeke (3). 

To rather selectively separate pertechnetate, with more than 90 % yield, from solutions of acid fission products it was proposed to use finely divided cadmium sulphide. The overall yield of the radionuclide pure c, finally extracted as [(C(,H5)4As TcC)4, was 68 % [182,183]. In addition, activated carbon was used to efficiently separate pertechnetate from high-level liquid waste. Distribution coefficients of more than 500 were observed when pertechnetate was separated with activated carbon from a 2 M HNO3 solution [184]. Effective separation and recovery of Tc04 from contaminated groundwater with activated carbon have been reported very recently [185. ... 

Feasibility of Separation and Utilization of Caesium and Strontium from High Level Liquid Waste, Technical Reports Series, No. 356, International Atomic Energy Agency, Vienna, 1993. 

They reported the distribution ratios (Dm) of lanthanide and actinide ions and compared the Dm values with that of Am " in the extraction system of 1 M HNO3 and 0.1 M TODGA/ M-dodecane as shown in Table 18.11. The order of extractability of actinide ions from 1 M HNO3 is An, An > An02 > An02. The TODGA has an ability of co-extraction of trivalent actinide ions and lanthanide ions from high-level liquid radioactive waste. 

The vendor claims that this technology will have four basic applications (1) on-site stabilization of high-level liquid radioactive waste (2) development of cheaper thermal and electrical energy sources (3) creation of scarce elements from more plentiful elements and (4) design and fabrication of table-top particle accelerators. 

High-Level Waste. There are approximately 285 million liters containing approximately 590 x 10 curies ( ) of military and 2.3 million liters of commercial high-level liquid waste (O presently stored in tanks. Although the volume of high-level military waste is much greater, the curie content of strontium 90 of both sources is approximately the same if stored spent fuel rods from commercial reactors are included in the inventory. The total curie content will be the same for both sources by 1985 at the present rate of use ( ). To date, there has been no disposal of any high-level waste. 

Wang, J., Song, C. 2001. Hot test of trialkyl phosphine oxide (TRPO) for removing actinides from highly saline high-level liquid waste (HLLW). Solvent Extr. Ion Exch. 19 (1) 231-242. 

Manohar, S., Sharma, J.N., Shah, B.V., Wattal, P.K. 2007. Process development for bulk separation of trivalent actinides and lanthanides from radioactive high-level liquid waste. Nuclear Science and Engineering 156 96-102. 

Morita, Y., Sasaki, Y., Tachimori, S. 2001. Development of TODGA extraction process for high level liquid waste. Preliminary evaluation of actinide separation by calculation. Global 2001 Back-end of the Fuel Cycle From Research to Solutions, September, Paris, France. 

The CTH actinide separation process was developed as a possible means to reduce the expected long term dose to man from a geologic repository containing solidified radioactive waste from the reprocessing of spent nuclear fuel The distribution data for the elements present in significant amounts in the high level liquid waste (HLLW) from a Purex plant, the general principles and the flowsheet have been described in detail elsewhere A... 

The results show that separation of metals from simulated high level liquid wastes is possible and that approximately 42 wt% of the metals can be recovered. From the experiments performed, there is some interaction between the metals and redox couples must exist as determined by the change in oxidation states of Cr, Ce, and Pr from +3 to +4. Periodic table Group I metals were found to remain in solution. It is not known at this point whether the metals in solution are unreacted nitrates or whether they have reacted to some species that are soluble in 1.6 M HN03. A simple model based on an adsorption model was found to adequately describe the data. Because of the experimental technique, it is not possible to know the precise metals and percentages that can be recovered from the solutions studied at supercritical conditions. More detailed experiments with a flow experiment and further research will answer many of these questions. This research on these points is in progress. 

Kondo, Y and Kuboto, M., Precipitation Behavior of Platinum Group Metals from Simulated High Level Liquid Waste in Sequential Denitration Process, J. Nucl. Sci. Technol., 29(2), (1992), ppl40-l48. 

To date the ICPP has produced approximately 4.6 million gal of high-level liquid waste of which 2.0 million gal are in the liquid form as shown in Table IV and 2.6 million have been calcined to a solid. High-level wastes began accumulating at the ICPP in 1953 and the rate of production has steadily increased (3). New wastes are anticipated from new fuels and will be discussed later in this chapter. 

Routine Releases. The high-level waste operations under consideration here are the storage of liquid waste, waste calcination, and storage of calcine in bins. In the 20 years of storing high-level liquid waste, there have been no instances of releases to the ground, nor even of leaks of waste from the tanks to their surrounding vaults. Similarly, there have... 

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