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Treatment of Spent Argentine Ion Exchange Resin Using Vitrification - Results of FY01 Testing at the Savannah River Technology Center

Description: Under the Science and Technology Implementing Arrangement for Cooperation on Radioactive and Mixed Waste Management (JCCRM), the Department of Energy (DOE) is helping to transfer waste treatment technology to international atomic energy commissions. In 1996, as part of the JCCRM, DOE established a collaborative research agreement with Argentina's Comision Nacional de Energia Atomica (CNEA). A primary mission of the CNEA is to direct waste management activities for Argentina's nuclear industry.
Date: August 14, 2002
Creator: Crawford, C.L.
Partner: UNT Libraries Government Documents Department

Copper Catalyzed Sodium Tetraphenylborate, Triphenylborane, Diphenylborinic Acid and Phenylboronic Acid Decomposition Kinetic Studies in Aqueous Alkaline Solutions

Description: This work studied the kinetics of copper-catalyzed decomposition of tetraphenylborate, triphenylborane, diphenylborinic acid and phenylboronic acid (NaTPB, 3PB, 2PB and 1PB, respectively) in aqueous alkaline solution over the temperature range of 25 to 70 degrees C. The statistically designed test matrices added copper sulfate to maximum concentrations of 10 mg/L. The relative rates of decomposition increase in the order of NaTPB < 1PB {tilde} 3PB < 2PB. Dependence of decomposition on the amount of added copper increases in the order of 3PB {tilde} 2PB < 1PB {tilde} NaTPB. Activation energies ranged from 82 to 143 kJ/mole over the temperature range studied. Final decomposition products predominately involved benzene and phenol. All 3PB, 2PB and 1PB intermediate phenylborate species proved relatively stable (< 8 percent decomposition over {tilde} 500 h) towards thermal hydrolysis in 1.5 M NaOH when contained in carbon-steel vessels sealed under air at ambient temperature (23 - 25 degrees C) with no added copper. Measurable (> 10-7 Mh-1) thermal hydrolysis of the phenylborate species occurs at 55 to 70 degrees C in alkaline (0.6-2.3 M OH-, 2-4.7 M Na+) solution with no added copper. The experiments suggest an important role for oxygen in copper-catalyzed phenylborate decomposition. NaTPB decomposes promptly under anoxic conditions while 3PB, 2PB and 1PB decompose faster in aerobic solutions. Benzene and phenol form as the predominant end-products from alkaline copper catalysis in static systems sealed under air. Both 2PB and 1PB decompose with near equal rates and quantitatively produce phenol under flowing air-purge conditions at 25 to 60 degrees C. Mechanisms for copper-catalyzed phenylborate decomposition likely involve a redox process giving loss of a phenyl group from the phenylborate with reduction of cupric ion, or dephenylation by reduced cuprous ion involving a phenylated copper intermediate.
Date: March 15, 1999
Creator: Crawford, C.L.
Partner: UNT Libraries Government Documents Department

Decomposition Studies of Tetraphenylborate Slurries

Description: This report details the decomposition of aqueous (K,Na) slurries in concentrated salt solutions using a more complete candidate catalyst recipe, extended testing temperatures (40-70 degrees C) and test durations of approximately 1500 hours (9 weeks). This study uses recently developed High-Pressure Liquid Chromatography (HPLC) methods for analysis of tetraphenylborate (TPB-), triphenylborane (3PB) and diphenylborinic acid (2PB). All of the present tests involve non-radioactive simulants and do not include investigations of radiolysis effects.
Date: May 6, 1997
Creator: Crawford, C.L.
Partner: UNT Libraries Government Documents Department

Crucible-Scale Active Vitrification Testing of a Hanford Envelope C Tank 241-AN-102

Description: The objectives of this work were to characterize and performance test the vitrified product and to provide RPP-WTP personnel with the results from these studies. This is the final report for the small scale active vitrification testing on the AN-102 sample.
Date: August 21, 2002
Creator: Crawford, C.L.
Partner: UNT Libraries Government Documents Department

Interim Report for Crucible-Scale Active Vitrification Testing Envelope B (AZ-102)

Description: The purposes of this work were to demonstrate the evaporation of AZ-102 supernate, demonstrate the vitrification of the evaporated concentrate in a crucible melt, and to demonstrate acceptance of the resulting glass by analysis (chemical and radionuclides) and durability testing.
Date: August 23, 2002
Creator: Crawford, C.L.
Partner: UNT Libraries Government Documents Department

Hanford Low-Level Waste Form Performance for Meeting Land Disposal Requirements

Description: Immobilized Low-activity waste (ILAW) from the Hanford site will be disposed of in near-surface burial grounds and must be processed into a chemically durable waste form to prevent release of hazardous constituents to the environment. To meet his goal, the LAW will be immobilized in borosilicate glass. the DOE office of River Protection and the Rive Protection Project-Waste Treatment Plant (RPP-WTP) project have agreed on testing requirements that the immobilized LAW glass must meet to demonstrate chemically durability. Two of the tests are the Product Consistency Test (PCT) and Environmental Protection Agency's (EPA) Toxicity Characteristic Leaching Procedure (TCLP). This paper provides results of RPP-WTP PCT and TCLP testing on both actual radioactive and non-radioactive simulant LAW glasses to show they meet the associated land disposal requirements.
Date: January 7, 2003
Creator: Crawford, C.L.
Partner: UNT Libraries Government Documents Department

Determination Of Reportable Radionuclides For DWPF Sludge Batch 7B (Macrobatch 9)

Description: The DWPF is receiving radioactive sludge slurry from HLW Tank 40. The radioactive sludge slurry in Tank 40 is a blend of the heel from Sludge Batch 7a (SB7a) and Sludge Batch 7b (SB7b) that was transferred to Tank 40 from Tank 51. The blend of sludge in Tank 40 is also referred to as Macrobatch 9 (MB9). This report develops the list of reportable radionuclides and associated activities as a function of time. Twenty-seven radionuclides have been identified as reportable for DWPF SB7b. Each of these radionuclides has a half-life greater than ten years and contributes more than 0.01% of the radioactivity on a Curie basis at some point from production through the 1100 year period between 2015 and 3115. For SB7b, all of the radionuclides in the Design Basis glass are reportable except for three radionuclides: Pd-107, Cs-135, and Th-230. At no time during the 1100- year period between 2015 and 3115 did any of these three radionuclides contribute to more than 0.01% of the radioactivity on a Curie basis. The radionuclide measurements made for SB7b are the most extensive conducted to date. Some method development/refinement occurred during the conduct of these measurements, leading to lower detection limits and more accurate measurement of some isotopes than was previously possible.
Date: December 17, 2012
Creator: Crawford, C. L. & Diprete, D. P.
Partner: UNT Libraries Government Documents Department

Determination Of Reportable Radionuclides For DWPF Sludge Batch 7B (Macrobatch 9)

Description: The Waste Acceptance Product Specifications (WAPS) 1.2 require that “The Producer shall report the inventory of radionuclides (in Curies) that have half-lives longer than 10 years and that are, or will be, present in concentrations greater than 0.05 percent of the total inventory for each waste type indexed to the years 2015 and 3115”. As part of the strategy to comply with WAPS 1.2, the Defense Waste Processing Facility (DWPF) will report for each waste type, all radionuclides (with half-lives greater than 10 years) that have concentrations greater than 0.01 percent of the total inventory from time of production through the 1100 year period from 2015 through 3115. The initial listing of radionuclides to be included is based on the design-basis glass as identified in the Waste Form Compliance Plan (WCP) and Waste Form Qualification Report (WQR). However, it is required that this list be expanded if other radionuclides with half-lives greater than 10 years are identified that may meet the greater than 0.01% criterion for Curie content. Specification 1.6 of the WAPS, International Atomic Energy Agency (IAEA) Safeguards Reporting for High Level Waste (HLW), requires that the ratio by weights of the following uranium and plutonium isotopes be reported: U-233, U-234, U-235, U-236, U-238, Pu-238, Pu-239, Pu-240, Pu-241, and Pu-242. Therefore, the complete set of reportable radionuclides must also include this set of U and Pu isotopes. The DWPF is receiving radioactive sludge slurry from HLW Tank 40. The radioactive sludge slurry in Tank 40 is a blend of the heel from Sludge Batch 7a (SB7a) and Sludge Batch 7b (SB7b) that was transferred to Tank 40 from Tank 51. The blend of sludge in Tank 40 is also referred to as Macrobatch 9 (MB9). This report develops the list of reportable radionuclides and associated activities as a function ...
Date: August 22, 2013
Creator: Crawford, C. L. & DiPrete, D. P.
Partner: UNT Libraries Government Documents Department

Sludge Washing And Demonstration Of The DWPF Flowsheet In The SRNL Shielded Cells For Sludge Batch 8 Qualification

Description: The current Waste Solidification Engineering (WSE) practice is to prepare sludge batches in Tank 51 by transferring sludge from other tanks to Tank 51. Tank 51 sludge is washed and transferred to Tank 40, the current Defense Waste Processing Facility (DWPF) feed tank. Prior to transfer of Tank 51 to Tank 40, the Savannah River National Laboratory (SRNL) typically simulates the Tank Farm and DWPF processes using a Tank 51 sample (referred to as the qualification sample). WSE requested the SRNL to perform characterization on a Sludge Batch 8 (SB8) sample and demonstrate the DWPF flowsheet in the SRNL shielded cells for SB8 as the final qualification process required prior to SB8 transfer from Tank 51 to Tank 40. A 3-L sample from Tank 51 (the SB8 qualification sample; Tank Farm sample HTF-51-12-80) was received by SRNL on September 20, 2012. The as-received sample was characterized prior to being washed. The washed material was further characterized and used as the material for the DWPF process simulation including a Sludge Receipt and Adjustment Tank (SRAT) cycle, a Slurry Mix Evaporator (SME) cycle, and glass fabrication and chemical durability measurements.
Date: April 26, 2013
Creator: Pareizs, J. M. & Crawford, C. L.
Partner: UNT Libraries Government Documents Department

Decomposition Studies of Triphenylboron, Diphenylborinic Acid and Phenylboric Acid in Aqueous Alkaline Solutions Containing Copper

Description: This report documents the copper-catalyzed chemical kinetics of triphenylboron, diphenylborinic acid and phenylboric acid (3PB, 2PB and PBA) in aqueous alkaline solution contained in carbon-steel vessels between 40 and 70 degrees C.
Date: February 11, 1997
Creator: Crawford, C.L. & Peterson, R. A.
Partner: UNT Libraries Government Documents Department

Effects of temperature and radiation on the nuclear waste glass product consistency leach test

Description: Previous leach studies carried out with monolithic glass samples have shown that glass dissolution rates increase with increasing temperature and may or may not increase on exposure to external gamma radiolysis. In this study we have investigated the effects of temperature (70--1200[degrees]C) and radiation on the dissolution of simulated radioactive waste glasses using the Product Consistency Test (PCT). The PCT is a seven day, crushed glass leach test in deionized water that is carried out at 9OO[degrees]C. To date our results indicate no significant effect of external Co--60 gamma radiation when testing various simulated waste glasses at 90[degrees]C in a wellinsulated compartment within a Gammacell 220 irradiation unit. The temperature dependence for glass dissolution clearly exhibits Arrheniustype behavior for two of the three glasses tested. For the third glass the dissolution decreases at the higher temperatures, probably due to saturation effects. Actual radioactive waste glasses will be investigated later as part of this study.
Date: January 1, 1993
Creator: Crawford, C.L. & Bibler, N.E.
Partner: UNT Libraries Government Documents Department

Analysis Of The Sludge Batch 7b (Macrobatch 9) DWPF Pour Stream Glass Sample

Description: The Defense Waste Processing Facility (DWPF) began processing Sludge Batch 7b (SB7b), also referred to as Macrobatch 9 (MB9), in January 2012. SB7b is a blend of the heel of Tank 40 from Sludge Batch 7a (SB7a) and the SB7b material that was transferred to Tank 40 from Tank 51. SB7b was processed using Frit 418. During processing of each sludge batch, the DWPF is required to take at least one glass sample to meet the objectives of the Glass Product Control Program (GPCP), which is governed by the DWPF Waste Form Compliance Plan, and to complete the necessary Production Records so that the final glass product may be disposed of at a Federal Repository. Two pour stream glass samples were collected while processing SB7b. The samples were transferred to the Savannah River National Laboratory (SRNL) where one was analyzed and the other was archived. The following conclusions were drawn from the analytical results provided in this report: The sum of oxides for the official SB7b pour stream glass is within the Product Composition Control System (PCCS) limits (95-105 wt%); The average calculated Waste Dilution Factor (WDF) for SB7b is 2.3. In general, the measured radionuclide content of the official SB7b pour stream glass is in good agreement with the calculated values from the Tank 40 dried sludge results from the SB7b Waste Acceptance Program Specification (WAPS) sample; As in previous pour stream samples, ruthenium and rhodium inclusions were detected by Scanning Electron Microscopy-Electron Dispersive Spectroscopy (SEM-EDS) in the SB7b pour stream sample; The Product Consistency Test (PCT) results indicate that the official SB7b pour stream glass meets the waste acceptance criteria for durability with a normalized boron release of 0.8 g/L, which is an order of magnitude less than the Environmental Assessment (EA) glass; The measured density of the ...
Date: November 18, 2013
Creator: Johnson, F. C.; Crawford, C. L. & Pareizs, J. M.
Partner: UNT Libraries Government Documents Department

Vitrification of Three Low-Activity Radioactive Waste Streams from Hanford

Description: As part of a demonstration for British Nuclear Fuels Limited, Incorporated (BNFL), the Immobilization Technology Section (ITS) of the Savannah River Technology Center (SRTC) has produced and characterized three low-activity waste (LAW) glasses from Hanford radioactive waste samples. The three LAW glasses were produced from radioactive supernate samples that had been treated by the Waste Processing Technology Section (WPTS) at SRTC to remove most of the radionuclides. These three glasses were produced by mixing the waste streams with between four and nine glass-forming chemicals in platinum/gold crucibles and heating the mixture to between 1120 and 1150 degrees C. Compositions of the resulting glass waste forms were close to the target compositions. Low concentrations of radionuclides in the LAW feed streams and, therefore, in the glass waste forms supported WPTS conclusions that pretreatment had been successful. No crystals were detected in the LAW glasses. In addition, all glass waste forms passed the leach tests that were performed. These included a 20 degrees C Product Consistency Test (PCT) and a modified version of the United States Environmental Protection Agency Toxicity Characteristic Leaching Procedure (TCLP).
Date: September 1, 1998
Creator: Ferrara, D.M.; Crawford, C.L.; Ha, B.C. & Bibler, N.E.
Partner: UNT Libraries Government Documents Department

Production of a High-Level Waste Glass from Hanford Waste Samples

Description: The HLW glass was produced from a HLW sludge slurry (Envelope D Waste), eluate waste streams containing high levels of Cs-137 and Tc-99, solids containing both Sr-90 and transuranics (TRU), and glass-forming chemicals. The eluates and Sr-90/TRU solids were obtained from ion-exchange and precipitation pretreatments, respectively, of other Hanford supernate samples (Envelopes A, B and C Waste). The glass was vitrified by mixing the different waste streams with glass-forming chemicals in platinum/gold crucibles and heating the mixture to 1150 degree C. Resulting glass analyses indicated that the HLW glass waste form composition was close to the target composition. The targeted waste loading of Envelope D sludge solids in the HLW glass was 30.7 wt percent, exclusive of Na and Si oxides. Condensate samples from the off-gas condenser and off-gas dry-ice trap indicated that very little of the radionuclides were volatilized during vitrification. Microstructure analysis of the HLW glass using Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Analysis (EDAX) showed what appeared to be iron spinel in the HLW glass. Further X-Ray Diffraction (XRD) analysis confirmed the presence of nickel spinel trevorite (NiFe2O4). These crystals did not degrade the leaching characteristics of the glass. The HLW glass waste form passed leach tests that included a standard 90 degree C Product Consistency Test (PCT) and a modified version of the United States Environmental Protection Agency Toxicity Characteristic Leaching Procedure (TCLP).
Date: September 1998
Creator: Crawford, C. L.; Farrara, D. M.; Ha, B. C. & Bibler, N. E.
Partner: UNT Libraries Government Documents Department

Apparent Benzene Solubility in Tetraphenylborate Slurries

Description: Personnel conducted testing to determine the apparent solubility of benzene in potassium tetraphenylborate (KTPB) slurries. The lack of benzene vapor pressure suppression in these tests indicate that for a 6.5 wt percent solids KTPB slurry in 4.65 M Na+ salt solution at approximately 25 degrees Celsius, no significant difference exists between the solubility of benzene in the slurry and the solubility of benzene in salt solution without KTPB solids. The work showed similar results in slurry with 6,000 mg/L sludge and 2,000 mg/L monosodium titanate added. Slurries containing tetraphenylborate decomposition intermediates (i.e., 4,200 mg/L triphenylboron (3PB), 510 mg/L diphenylborinic acid (2PB) and 1,500 mg/L phenylboric acid (1PB) or 100 mg/L tri-n-butylphosphate (TBP)) also showed no significant difference in benzene solubility form filtrate containing no KTPB solids. Slurry containing 2,000 mg/L Surfynol 420 did exhibit significant additional benzene solubility, as did irradiated slurries. The vapor pressure depression in the irradiated slurries presumably results from dissolution of biphenyl and other tetraphenylborate irradiation products in the benzene.
Date: November 1, 1997
Creator: Swingle, R.F.; Peterson, R.A. & Crawford, C.L.
Partner: UNT Libraries Government Documents Department

Decomposition of triphenylborane with enhanced comprehensive catalyst under aerated and inert conditions

Description: This work investigated the decomposition of triphenylborane in a statistically-designed set of tests to determine the effects of four process variables: temperature, hydroxide concentration, catalyst concentration, and atmosphere. Analysis of these tests provide the following conclusions:(1) The presence of tetraphenylborate solids facilitate a 10X increase in the rate of decomposition of triphenylborane, (2) The presence of oxygen slows the decomposition of triphenylborane, (3) The activation energy of the decomposition reaction in the presence of oxygen (59.88 + 27.73 kJ/mol) is statistically lower than inerted systems (99.11 + 10.14 kJ/mol), (4) Rate constants derived from the nitrogen inerted tests encompass the rate constants from previous tests with slurries. These rate constants agree reasonably with similar values obtained from Tank 48H operations at ambient temperatures, and (5) For test conducted in air, the decomposition reaction rate constant correlated with the catalyst concentration. In tests inerted by nitrogen, the same correlation did not hold.
Date: September 30, 1997
Creator: Wilmarth, W.R.; Crawford, C.L.; Peterson, R.A. & White, T.L.
Partner: UNT Libraries Government Documents Department

Vitrification of Three Low-Activity Radioactive Waste Streams from Hanford

Description: The Savannah River Technology Center (SRTC) used radioactive waste samples from Hanford to demonstrate a process being considered by British Nuclear Fuels Limited, Incorporated (BNFL) for immobilization of this waste. The paper being outlined in this summary will describe vitrification of the low-activity waste (LAW) streams resulting when three radioactive supernate samples were treated to remove the major radionuclides. Characterization of the resulting glass waste form showed that it met waste loading, durability, and leach resistance requirements set by the Department of Energy (DOE).
Date: July 1, 1998
Creator: Ferrara, D.; Crawford, C.L.; Ha, B.C. & Bibler, N.E.
Partner: UNT Libraries Government Documents Department

Decomposition studies of filtered slurries using the enhanced comprehensive catalyst

Description: This study examined decomposition of the soluble phenylborates at elevated temperatures (45 degrees Celsius) to determine the effects of filtering the solid tetraphenylborate, solid sludge and monosodium titanate and spiking additional levels of transition metal catalyst.
Date: November 13, 1997
Creator: Wilmarth, W.R.; Crawford, C.L. & Peterson, R.A.
Partner: UNT Libraries Government Documents Department

Immobilization of the Radionuclides from Spent Ion-Exchange Resins Using Vitrification

Description: Approximately 60 g of an iron-enriched borosilicate glass was made in the radiochemical labs of the Savannah River Technology Center (SRTC). The glass was made to demonstrate the immobilization of the radioisotopes contained on representative Argentine ion exchange resins (similar to those used at the Embalse plant). The product was approximately 90% amorphous and was quite durable as measured by the release rates from the Product Consistency Test (PCT). The release rates were considerably better than those of the U. S. High Level Waste (HLW) benchmark DWPF EA glass. The release rate of the Cs-137 was predictably similar to that of Na and Li. No Co-60 or Sr-90 was measured in the PCT leachate. The mass balances for the inactive additives were quite good. Of the radioisotopes, approximately 71% of Cs-137 was accounted for in the glass product. This was similar to the Na mass balance. Approximately 89% of the Co-60 was accounted for in the glass product.
Date: February 25, 2002
Creator: Hutson, N. D.; Crawford, C. L.; Russo, D. O. & Sterba, M. E.
Partner: UNT Libraries Government Documents Department

Radiolytic gas generation in salt cake technical task plan

Description: High-level radioactive wastes are stored in large, steel tanks in the Savannah River Site Tank Farms. The liquid levels in these tanks are monitored to detect leakage of waste out of tanks or leakage of liquids into the tanks. Recent unexplained level fluctuations in high-level waste (HLW) tanks have caused High Level Waste Engineering (HLWE) to develop a program to better understand tank level behavior. Interim Waste Technology (IWT) has been requested by HLWE to obtain data which will lead to a better understanding of the radiolytic generations of gases in salt cake. The task described below will provide data from laboratory experiments with simulated wastes which can be used in tank level fluctuation modeling. The following experimental programs have been formulated to meet the task requirements of the customer: (A) determine whether radiolytically generated gas bubbles can be trapped in salt cake; (B) determine the composition of gases produced by radiolysis; (C) determine the yield of radiolysis gases as a function of radiation dose; (D) determine bubble distribution.
Date: August 29, 1993
Creator: Walker, D. D.; Crawford, C. L. & Bibler, N. E.
Partner: UNT Libraries Government Documents Department

Evaluation of Foaming and Antifoam Effectiveness During the WTP Oxidative Leaching Process

Description: The River Protection Project-Waste Treatment Plant (RPP-WTP) requested Savannah River National Laboratory (SRNL) to conduct small-scale foaming and antifoam testing using a Hanford waste simulant subjected to air sparging during oxidative leaching. The foaminess of Hanford tank waste solutions was previously demonstrated by SRNL during WTP evaporator foaming studies and in small scale air sparger studies. The commercial antifoam, Dow Corning Q2-3183A was recommended to mitigate the foam in the evaporators and in vessel equipped with pulse jet mixers and air spargers. Currently, WTP is planning to use air spargers in the HLW Lag Storage Vessels (HLP-VSL-00027A/B), the Ultrafiltration Vessels (UFP-VSL-00002A&amp;B), and the HLW Feed Blend Vessel (HLPVSL-00028) to assist the performance of the Pulse Jet Mixers (PJM). The previous air sparger antifoam studies conducted by SRNL researchers did not evaluate the hydrogen generation rate expected from antifoam additions or the effectiveness of the antifoam during caustic leaching or oxidative leaching. The fate of the various antifoam components and breakdown products in the WTP process under prototypic process conditions (temperature & radiation) was also not investigated. The effectiveness of the antifoam during caustic leaching, expected hydrogen generation rate associated with antifoam addition, and the fate of various antifoam components are being conducted under separate SRNL research tasks.
Date: October 11, 2005
Creator: Burket, P. R.; Jones, T. M.; White, T. L.; Crawford, C. L. & Calloway, T. B
Partner: UNT Libraries Government Documents Department

Off-Gas Analysis During the Vitrification of Hanford Radioactive Waste Samples

Description: This paper describes the off-gas analysis of samples collected during the radioactive vitrification experiments. Production and characterization of the Hanford waste-containing LAW and HAW glasses are presented in related reports from this conference.
Date: March 1, 1998
Creator: Ha, B.C.; Ferrara, D.M.; Crawford, C.L.; Choi, A.S. & Bibler, N.E.
Partner: UNT Libraries Government Documents Department