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Cesium-137 Research Irradiator

Description: Abstract: A 12,000 curie cesium-137 research irradiator has been designed and installed on the Georgia Tech campus. The evaluation of the physical characteristics of the irradiator has been completed.
Date: April 20, 1961
Creator: Carter, R. W.; Palmer, R. C. & Willis, W. V.
Partner: UNT Libraries Government Documents Department

The Development of an Improved Thermionic Energy Converter: Third Quarterly Technical Report

Description: From introduction: The objective of the current program is to determine the feasibility of the reservoirless converter operation by conducting a series of tests on operating thermionic converters which contain cesium in the vapor phase only.
Date: April 1965
Creator: Radio Corporation of America. Direct Energy Conversion Department.
Partner: UNT Libraries Government Documents Department

Strontium Program: Quarterly Summary Report, January 1, 1960

Description: From Abstract: "This report is one of the a sequence of quarterly reports, each designed to up-date its predecessor beginning with HASL-42, "Environmental Contamination from Weapon Tests." Herein are presented data accrued since HASL-69. Plutonium-239 and cesium-137 levels in human tissue and other biological materials are also presented."
Date: January 1, 1960
Creator: Hardy, Edward P., Jr. & Klein, Stanley
Partner: UNT Libraries Government Documents Department

Next Generation Solvent Development for Caustic-Side Solvent Extraction of Cesium

Description: This report summarizes the FY 2010 and 2011 accomplishments at Oak Ridge National Laboratory (ORNL) in developing the Next Generation Caustic-Side Solvent Extraction (NG-CSSX) process, referred to commonly as the Next Generation Solvent (NGS), under funding from the U.S. Department of Energy, Office of Environmental Management (DOE-EM), Office of Technology Innovation and Development. The primary product of this effort is a process solvent and preliminary flowsheet capable of meeting a target decontamination factor (DF) of 40,000 for worst-case Savannah River Site (SRS) waste with a concentration factor of 15 or higher in the 18-stage equipment configuration of the SRS Modular Caustic-Side Solvent Extraction Unit (MCU). In addition, the NG-CSSX process may be readily adapted for use in the SRS Salt Waste Processing Facility (SWPF) or in supplemental tank-waste treatment at Hanford upon appropriate solvent or flowsheet modifications. Efforts in FY 2010 focused on developing a solvent composition and process flowsheet for MCU implementation. In FY 2011 accomplishments at ORNL involved a wide array of chemical-development activities and testing up through single-stage hydraulic and mass-transfer tests in 5-cm centrifugal contactors. Under subcontract from ORNL, Argonne National Laboratory (ANL) designed a preliminary flowsheet using ORNL cesium distribution data, and Tennessee Technological University developed a chemical model for cesium distribution ratios (DCs) as a function of feed composition. Inter Laboratory efforts were coordinated in complementary fashion with engineering tests carried out (and reported separately) by personnel at Savannah River National Laboratory (SRNL) and Savannah River Remediation (SRR) with helpful advice by Parsons Engineering and General Atomics on aspects of possible SWPF implementation.
Date: July 1, 2013
Creator: Duncan, Nathan C; Delmau, Laetitia Helene; Ensor, Dale; Lee, Denise L; Birdwell Jr, Joseph F; Hill, Talon G et al.
Partner: UNT Libraries Government Documents Department

Recommended Guanidine Suppressor for the Next-Generation Caustic-Side Solvent Extraction Process

Description: The guanidine recommended for the Next-Generation Caustic-Side is N,N ,N -tris(3,7-dimethyloctyl)guanidine (TiDG). Systematic testing has shown that it is significantly more lipophilic than the previously recommended guanidine DCiTG, the active extractant in the commercial guanidine product LIX -79, while not otherwise changing the solvent performance. Previous testing indicated that the extent of partitioning of the DCiTG suppressor to the aqueous strip solution is significantly greater than expected, potentially leading to rapid depletion of the suppressor from the solvent and unwanted organic concentrations in process effluents. Five candidate guanidines were tested as potential replacements for DCiTG. The tests included batch extraction with simulated waste and flowsheet solutions, third-phase formation, emulsion formation, and partition ratios of the guanidine between the solvent and aqueous strip solution. Preliminary results of a thermal stability test of the TiDG solvent at one month duration indicated performance approximately equivalent to DCiTG. Two of the guanidines proved adequate in all respects, and the choice of TiDG was deemed slightly preferable vs the next best guanidine BiTABG.
Date: January 1, 2013
Creator: Moyer, Bruce A; Delmau, Laetitia Helene; Duncan, Nathan C; Ensor, Dale; Hill, Talon G; Lee, Denise L et al.
Partner: UNT Libraries Government Documents Department

Solvent Blending Strategy to Upgrade MCU CSSX Solvent to Equivalent Next-Generation CSSX Solvent

Description: The results of the present study have validated an equal-volume blending strategy for upgrading freshly prepared CSSX solvent to a blended solvent functionally equivalent to NG-CSSX solvent. It is shown that blending fresh CSSX solvent as currently used in MCU with an equal volume of an NG-CSSX solvent concentrate of appropriate composition yields a blended solvent composition (46.5 mM of MaxCalix, 3.5 mM of BOBCalixC6, 0.5 M of Cs-7SB, 3 mM of guanidine suppressor, and 1.5 mM of TOA in Isopar L) that exhibits equivalent batch ESS performance to that of the NG-CSSX solvent containing 50 mM of MaxCalix, 0.5 M of Cs-7SB, and 3 mM of guanidine suppressor in Isopar L. The solvent blend composition is robust to third-phase formation. Results also show that a blend containing up to 60% v/v of CSSX solvent could be accommodated with minimal risk. Extraction and density data for the effect of solvent concentration mimicking diluent evaporation or over-dilution of the equal-volume blended solvent are also given, providing input for setting operational limits. Given that the experiments employed all pristine chemicals, the results do not qualify a blended solvent starting with actual used MCU solvent, which can be expected to have undergone some degree of degradation. Consequently, further work should be considered to evaluate this risk and implement appropriate remediation if needed.
Date: December 1, 2012
Creator: Delmau, Laetitia Helene & Moyer, Bruce A
Partner: UNT Libraries Government Documents Department

Alkaline-Side Extraction of Cesium from Savannah River Tank Waste Using a Calixarene-Crown Ether Extractant

Description: Results are presented supporting the viability of the alkaline-side CSEX process as a potential replacement for the In-Tank Precipitation process for removal of cesium from aqueous high-level waste (HLW) at the Savannah River Site (SRS). Under funding from the USDOE Efficient Separations and Crosscutting program, a flowsheet was suggested in early June of 1998, and in the following four months, this flowsheet underwent extensive testing, both in batch tests at ORNL and ANL and in two centrifugal-contactor tests at ANL. To carry out these tests, the initial ESP funding was augmented by direct funds from Westinghouse Savannah River Corporation. The flowsheet employed a solvent containing a calixarene-crown hybrid compound called BoBCalixC6 that was invented at ORNL and can now be obtained commercially for government use from IBC Advanced Technologies. This special extractant is so powerful and selective that it can be used at only 0.01 M, compensating for its expense, but a modifier is required for use in an aliphatic diluent, primarily to increase the cesium distribution ratio D{sub Cs} in extraction. The modifier selected is a relatively economical fluorinated alcohol called Cs3, invented at ORNL and so far available. only from ORNL. For the flowsheet, the modifier is used at 0.2 M in the branched aliphatic kerosene Isopar{reg_sign} L. Testing at ORNL and ANL involved simulants of the SRS HLW. After extraction of the Cs from the waste simulant, the solvent is scrubbed with 0.05 M HNO{sub 3} and stripped with a solution comprised of 0.0005 M HNO{sub 3} and 0.0001 M CsNO{sub 3}. The selection of these conditions is justified in this report, both on the basis of experimental data and underlying theory.
Date: December 1, 1998
Creator: Bonnesen, P.V.; Delmau, L.H.; Haverlock, T.J. & Moyer, B.A.
Partner: UNT Libraries Government Documents Department

Development Program for Magnetically Assisted Chemical Separation : Evaluation of Cesium Removal from Hanford Tank Supernatant

Description: Magnetic particles (MAG*SEP(sup SM)) coated with various absorbents were evaluated for the separation and recovery of low concentrations of cesium from nuclear waste solutions. The MAG*SEP(sup SM) particles were coated with (1) clinoptilolite, (2) transylvanian volcanic tuff, (3) resorcinol formaldehyde, and (4) crystalline silico-titanate, and then were contacted with a Hanford supernatant simulant. Particles coated with the crystalline silico-titanate were identified by Bradtec as having the highest capacity for cesium removal under the conditions tested (variation of pH, ionic strength, cesium concentration, and absorbent/solution ratio). The MAG*SEP(sup SM) particles coated with resorcinol formaldehyde had high distribution ratios values and could also be used to remove cesium from Hanford supernant simulant. Gamma irradiation studies were performed on the MAG*SEP(sup SM) particles with a gamma dose equivalent to 100 cycles of use. This irradiation decreased the loading capacity and distribution ratios for the particles by greater than 75%. The particles demonstrated high sensitivity to radiolytic damage due to the degradation of the polymeric regions. These results were supported by optical microscopy measurements. Overall, use of magnetic particles for cesium separation under nuclear waste conditions was found to be marginally effective.
Date: December 1994
Creator: Nuñez, Luis
Partner: UNT Libraries Government Documents Department

Final Report: The Cesium-137 Power Program

Description: From introduction: The technology of isotopic power generation, though recent, is a logical extension of the search for power from the atom. Controlled fission of uranium utilizes only a fraction of the total energy made available from this nuclear process.
Date: May 1964
Partner: UNT Libraries Government Documents Department

MINERAL AND SEDIMENT AFFINITY FOR RADIONUCLIDES

Description: In determining radionuclide sorption by clay minerals, shortcomings in the filtration technique for solid separation and in the contact times selected for testing were noted. Filters were found to have a high affinity for cesium and strontium when these elements were present in tracerlevel concentrations. Sorption equilibrium was not established in 24 hr, and the contact time was extended to 7 days. The affinity of the clay minerals illite, kaolinite, montmorillonite, and vermiculite for selected radionuclides was established after these shortcomings in the testing procedure were corrected. Illite exhibited a very high affinity for Cs/sup 137/ (K/sub d/ =200,000 after 7-day contact); none of the clay minerals demonstrated exceptionally high affinity for strontium (K/ sub d/ = 4000 for kaolinite, which was the highest measured value). The behavior of cobalt and zirconium-niobium was complicated by the colloidal nature of the elements. The uptake of the above radionuclides by a composited sample of Clinch River sediment showed that cesium and strontium behaved in accordance with the mineralogic character of the sediment. The sediment sorbed more cobalt than was accountable by the mineral composition; organic matter interactions with the cobalt are thereby suspected. (auth)
Date: July 25, 1960
Creator: Sorathesn, A; Bruscia, G; Tamura, T & Struxness, E G
Partner: UNT Libraries Government Documents Department

EFFECTIVE HALF-LIFE OF CESIUM-137 IN VARIOUS ENVIRONMENTAL MEDIA AT THE SAVANNAH RIVER SITE

Description: During the operational history of the Savannah River Site (SRS), many different radionuclides have been released from site facilities into the SRS environment. However, only a relatively small number of pathways, most importantly {sup 137}Cs in fish and deer, have contributed significantly to doses and risks to the public. The “effective” half-lives (T{sub e}) of {sup 137}Cs (which include both physical decay and environmental dispersion) in Savannah River floodplain soil and vegetation and in fish and white-tailed deer from the SRS were estimated using long-term monitoring data. For 1974–2011, the T{sub e}s of {sup 137}Cs in Savannah River floodplain soil and vegetation were 17.0 years (95% CI = 14.2–19.9) and 13.4 years (95% CI = 10.8–16.0), respectively. These T{sub e}s were greater than in a previous study that used data collected only through 2005 as a likely result of changes in the flood regime of the Savannah River. Field analyses of {sup 137}Cs concentrations in deer collected during yearly controlled hunts at the SRS indicated an overall T{sub e} of 15.9 years (95% CI = 12.3–19.6) for 1965–2011; however, the T{sub e} for 1990–2011 was significantly shorter (11.8 years, 95% CI = 4.8–18.8) due to an increase in the rate of {sup 137}Cs removal. The shortest T{sub e}s were for fish in SRS streams and the Savannah River (3.5–9.0 years), where dilution and dispersal resulted in rapid {sup 137}Cs removal. Long-term data show that T{sub e}s are significantly shorter than the physical half-life of {sup 137}Cs in the SRS environment but that they can change over time. Therefore, it is desirable have a long period of record for calculating Tes and risky to extrapolate T{sub e}s beyond this period unless the processes governing {sup 137}Cs removal are clearly understood.
Date: December 12, 2013
Creator: Jannik, T.; Paller, M. & Baker, R.
Partner: UNT Libraries Government Documents Department

ACCUMULATION OF RADIOCESIUM BY MUSHROOMS IN THE ENVIRONMENT: A LITERATURE REVIEW AND IMAGE GALLERY

Description: During the last 50 years, a large amount of information on radionuclide accumulators or 'sentinel-type' organisms in the environment has been published. Much of this work focused on the risks of food-chain transfer of radionuclides to higher organisms such as reindeer and man. However, until the 1980's and 1990's, there has been little published data on the radiocesium ({sup 134}Cs and {sup 137}Cs) accumulation by mushrooms. This presentation will consist of a review of the published data for {sup 134,137}Cs accumulation by mushrooms in nature. The review will consider the time of sampling, sample location characteristics, the radiocesium source term and other aspects that promote {sup 134,137}Cs uptake by mushrooms. This review will focus on published data for mushrooms that demonstrate a large propensity for use in the environmental biomonitoring of radiocesium contamination. It will also provide photographs and descriptions of habitats for many of these mushrooms to facilitate their collection for biomonitoring.
Date: November 5, 2006
Creator: Duff, M & Mary Ramsey, M
Partner: UNT Libraries Government Documents Department

Hydraulic Performance and Gas Behavior of a Tall Crystalline Silicotitanate Ion-Exchange Column

Description: Crystalline silicotitanate (CST) sorbent is one of several technologies being evaluated by the Savannah River Site (SRS) for removing cesium from high-level tank-waste supernatant. As currently envisioned, three large 5-ft-diam, 20-ft-high ion-exchange columns will be operated in series at a superficial velocity of 4.1 cm/min. The CST will be subjected to a high radiation field from the sorbed cesium. The tests described in this work were conducted to evaluate column hydraulics, to identify changes in the CST particles during operation, to explore how radiolytic gases generated during operation behave, and to demonstrate sluicing of CST into and out of columns.
Date: February 1, 2000
Creator: Welch, T.D.; Anderson, K.K.; Bostick, D.A.; Dillow, T.A.; Getting, M.W.; Hunt, R.D. et al.
Partner: UNT Libraries Government Documents Department

Decision document for the final disposition of cesium and strontium capsules

Description: This report was prepared to document decisions regarding the disposition of cesium and strontium capsules. A Decision Support Board was established to consider the multiple drivers for decisions regarding disposition of cesium and strontium capsules and make decisions that form the near-term guidance for the project. The decision process included several Decision Board meetings, documented in this report, in which technical and programmatic information was presented by Tank Waste Remediation System (TWRS) technical staff and considered by the Decision Board. The process also included preparation of the decision documentation, which is presented in this report.
Date: March 1, 1997
Creator: Claghorn, R.D., Fluor Daniel Hanford
Partner: UNT Libraries Government Documents Department

Analysis of water from K west basin canisters (second campaign)

Description: Gas and liquid samples have been obtained from a selection of the approximately 3,820 spent fuel storage canisters in the K West Basin. The samples were taken to characterize the contents of the gas and water in the canisters. The data will provide source term information for two subprojects of the Spent Nuclear Fuel Project (SNFP) (Fulton 1994): the K Basins Integrated Water Treatment System subproject (Ball 1996) and the K Basins Fuel Retrieval System subproject (Waymire 1996). The barrels of ten canisters were sampled in 1995, and 50 canisters were sampled in a second campaign in 1996. The analysis results for the gas and liquid samples of the first campaign have been reported (Trimble 1995a; Trimble 1995b; Trimble 1996a; Trimble 1996b). An analysis of cesium-137 (137CS ) data from the second campaign samples was reported (Trimble and Welsh 1997), and the gas sample results are documented in Trimble 1997. This report documents the results of all analytes of liquid samples from the second campaign.
Date: March 6, 1997
Creator: Trimble, D.J., Fluor Daniel Hanford
Partner: UNT Libraries Government Documents Department