Download or read book Preliminary Ion Exchange Modeling for Removal of Technetium from Hanford Waste Using SuperLig 639 Resin written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: A proposed facility is being designed for the immobilization of Hanford underground storage tank radioactive waste. The waste is pretreated to split it into Low Activity Waste (LAW) and High Level Waste (HLW) streams for separate vitrification. One unit process in the facility is designed to remove radioactive technetium by ion-exchange from a highly alkaline aqueous phase.
Download or read book Upgrade to Ion Exchange Modeling for Removal of Technetium from Hanford Waste Using SuperLig 639 Resin written by and published by . This book was released on 2013 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report documents the development and application of computer models to describe the sorption of pertechnetate [TcO4−], and its surrogate perrhenate [ReO4−], on SuperLig® 639 resin. Two models have been developed: 1) A thermodynamic isotherm model, based on experimental data, that predicts [TcO4−] and [ReO4−] sorption as a function of solution composition and temperature and 2) A column model that uses the isotherm calculated by the first model to simulate the performance of a full-scale sorption process. The isotherm model provides a synthesis of experimental data collected from many different sources to give a best estimate prediction of the behavior of the pertechnetate-SuperLig® 639 system and an estimate of the uncertainty in this prediction. The column model provides a prediction of the expected performance of the plant process by determining the volume of waste solution that can be processed based on process design parameters such as column size, flow rate and resin physical properties.
Download or read book Evaluation of SuperLig 639 Ion Exchange Resin for the Removal of Rhenium from Hanford Envelope A Simulant written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hanford Radioactive Waste materials have been categorized into four envelopes labeled A through D as specified in the Tank Waste Remediation Contract between BNFL and DOE. 1 Envelopes A, B and C contain only solubilized species and are specified as Low-Activity Waste (LAW). Each envelope is defined based on compositional maximums of chemical and radioactive constituents. Envelopes A and B contain low concentrations of organic species and the primary form of technetium is pertechnetate (TcO4- ). Envelope C contains higher levels of organic species and technetium which is primarily in the nonpertechnetate form (presumably complexed TcO2). Envelope D is sludge which has been separated from the supernate and is referred to as High Activity Waste. The current plant design utilizes SuperLig ion exchange resins to remove cesium and technetium (the primary radioactive constituents) from the Hanford LAW. The process is designed to produce a decontaminated waste stream and a concentrated eluate waste stream for vitrification into low and high activity glasses, respectively.
Download or read book Ion Exchange Distribution Coefficient Tests and Computer Modeling at High Ionic Strength Supporting Technetium Removal Resin Maturation written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary treatment of the tank waste at the DOE Hanford site will be done in the Waste Treatment and Immobilization Plant (WTP) that is currently under construction. The baseline plan for this facility is to treat the waste, splitting it into High Level Waste (HLW) and Low Activity Waste (LAW). Both waste streams are then separately vitrified as glass and poured into canisters for disposition. The LAW glass will be disposed onsite in the Integrated Disposal Facility (IDF). There are currently no plans to treat the waste to remove technetium, so its disposition path is the LAW glass. Due to the water solubility properties of pertechnetate and long half-life of 99Tc, effective management of 99Tc is important to the overall success of the Hanford River Protection Project mission. To achieve the full target WTP throughput, additional LAW immobilization capacity is needed, and options are being explored to immobilize the supplemental LAW portion of the tank waste. Removal of 99Tc, followed by off-site disposal, would eliminate a key risk contributor for the IDF Performance Assessment (PA) for supplemental waste forms, and has potential to reduce treatment and disposal costs. Washington River Protection Solutions (WRPS) is developing some conceptual flow sheets for supplemental LAW treatment and disposal that could benefit from technetium removal. One of these flowsheets will specifically examine removing 99Tc from the LAW feed stream to supplemental immobilization. To enable an informed decision regarding the viability of technetium removal, further maturation of available technologies is being performed. This report contains results of experimental ion exchange distribution coefficient testing and computer modeling using the resin SuperLig® 639a to selectively remove perrhenate from high ionic strength simulated LAW. It is advantageous to operate at higher concentration in order to treat the waste stream without dilution and to minimize the volume of the final wasteform. This work examined the impact of high ionic strength, high density, and high viscosity if higher concentration LAW feed solution is used. Perrhenate (ReO4- ) has been shown to be a good nonradioactive surrogate for pertechnetate in laboratory testing for this ion exchange resin, and the performance bias is well established. Equilibrium contact testing with 7.8 M [Na+] average simulant concentrations indicated that the SuperLig® 639 resin average perrhenate distribution coefficient was 368 mL/g at a 100:1 phase ratio. Although this indicates good performance at high ionic strength, an equilibrium test cannot examine the impact of liquid viscosity, which impacts the diffusivity of ions and therefore the loading kinetics. To get an understanding of the effect of diffusivity, modeling was performed, which will be followed up with column tests in the future.
Download or read book Small Scale Ion Exchange Removal of Cesium and Technetium from Hanford Tank 241 AN 103 written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The pretreatment process for BNFL, Inc.'s Hanford River Protection Project is to provide decontaminated low activity waste and concentrated eluate streams for vitrification into low activity and high level waste glass, respectively. The pretreatment includes sludge washing, filtration, precipitation, and ion exchange processes to remove entrained solids, cesium, transuranics, technetium, and strontium. The ion exchange removal of cesium (Cs) and technetium (Tc) ions is accomplished by using SuperLig 644, and 639 resins from IBC Advanced Technologies, American Fork, Utah. The resins were shown to selectively remove cesium and technetium (as pertechnetate), from alkaline salt solutions. The efficiency of ion exchange column loading and elution is a complex function involving feed compositions, equilibrium and kinetic behavior of ion exchange resins, diffusion, and the ionic strength and pH of the aqueous solution. A previous experimental program completed at the Savannah River Technology Center demonstrated the conceptualized flow sheet parameters with a similar Hanford tank sample (241-AW-101). Those experiments included determination of Cs and Tc batch distribution coefficients by SuperLig 644 and 639 resins and demonstration of small-scale column breakthrough and elution. The experimental findings were used in support of preliminary design bases and pretreatment flow sheet development by BNFL, Inc.
Download or read book Comprehensive Scale Testing of the Ion Exchange Removal of Cesium and Technetium from Hanford Tank Wastes written by and published by . This book was released on 2001 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Highly selective ion exchange materials will be used to remove radionuclides from tank waste at the Hanford site as part of the River Protection Project. Testing in support of facility design was performed with different sizes of ion exchange columns to provide a basis for comparing results obtained using small-scale with radioactive samples and full design-height (i.e., pilot-scale) with simulant. Results indicate good comparison between small-scale radioactive tests and pilot-scale simulant tests. Because of the cost of performing radioactive tests and the unavailability of large sample volumes, understanding scale-up of performance parameters is critical to ensure that the system will perform as designed. The consistency of scale-up of ion exchange columns using SuperLig 644 and 639 resins has been demonstrated. Maintaining constant residence time, i.e., Column Volumes per hour, yields similar breakthrough profiles with resin columns ranging from 3.5 cm to 230 cm in height. Experiments performed with flow rates greatly exceeding the design parameters provided valuable information on loading and diffusion parameters. These data will be used, along with a computer model, to permit verification of design and prediction of column performance.
Download or read book Multiple Ion Exchange Column Tests for Technetium Removal from Hanford Tank Waste Supernate written by and published by . This book was released on 2004 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Five cycles of loading, elution, and regeneration were performed to remove technetium from a Hanford waste sample retrieved from Tank 241-AW-101 using SuperLig 639 resin. The waste sample was diluted to 4.95 M Na plus and then was processed to remove 137Cs through dual ion exchange columns each containing 15 mL of SuperLig 644. To remove 99Tc, the cesium decontaminated solution was processed downwards through two ion exchange columns, each containing 12 mL of SuperLig 639 resin. The columns, designated as lead and lag, each had an inside diameter of 1.45 cm and a height of 30 cm. The columns were loaded in series, but were eluted and then regenerated separately. The average technetium loading for the cycles was 250 BV at 10 percent breakthrough. There was no significant difference in the loading performances among the five cycles. The percent removal of 99Tc was greater than 99.94 percent and the average decontamination factor (DF) was approximately 1.7 x 103. Approximately 99 percent of the 99Tc loaded on the resin was eluted with less than 15 BV of de-ionized water at 65 degrees C.
Download or read book Small Scale Ion Exchange Removal of Cesium and Technetium from Hanford Tank 241 AN 102 written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The pretreatment process for BNFL, Inc.'s Hanford River Protection Project is to provide decontaminated low activity waste and concentrated eluate streams for vitrification into low and high activity waste glass, respectively. The pretreatment includes sludge washing, filtration, precipitation, and ion exchange processes to remove entrained solids, cesium, transuranics, technetium, and strontium. The cesium (Cs-137) and technetium (Tc-99) ion exchange removal is accomplished by using SuperLig 644, and 639 resins from IBC Advanced Technologies, American Fork, Utah. The resins were shown to selectively remove cesium and technetium (as anionic pertechnetate) from alkaline salt solutions. The efficiency of ion exchange column loading and elution is a complex function involving feed compositions, equilibrium and kinetic behavior of ion exchange resins, diffusion, and the ionic strength and pH of the aqueous solution. A previous experimental program completed at the Savannah River Tech nology Center2 demonstrated the conceptualized flow sheet parameters with an Envelope C sample from Hanford Tank 241-AN-107. Those experiments also included determination of Cs and Tc batch distribution coefficients by SuperLig 644 and 639 resins and demonstration of small-scale column breakthrough and elution. The experimental findings were used in support of preliminary design bases and pretreatment flow sheet development by BNFL, Inc.
Download or read book Preliminary Ion Exchange Modeling for Removal of Cesium from Hanford Waste Using Hydrous Crystalline Silicotitanate Material written by and published by . This book was released on 2004 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the current pretreatment facility design of the River Protection Project (RPP) Waste Treatment Plant (WTP), the removal of cesium from low activity waste (LAW) is achieved by ion-exchange technology based on SuperLig(R) 644 resin. Due to recent concerns over potential radiological and chemical degradation of SuperLig(R) 644 resin and increased pressure drops observed during pilot-scale column studies, an increased interest in developing a potential backup ion-exchanger material has resulted. Ideally, a backup ion-exchanger material would replace the SuperLig(R) 644 resin and have no other major impacts on the pretreatment facility flowsheet. Such an ideal exchanger has not been identified to date. However, Crystalline Silicotitanate (CST) ion-exchanger materials have been studied for the removal of cesium from a variety of DOE wastes over the last decade. CST ion-exchanger materials demonstrate a high affinity for cesium under high alkalinity conditions and have been under investigation for cesium removal specifically at Hanford and SRS during the last six years. Since CST is an inorganic based material (with excellent properties in regard to chemical, radiological, and thermal stability) that is considered to be practically non-elutable (while SuperLig(R) 644 is an organic based elutable resin), the overall pretreatment facility flowsheet would be impacted in various ways. However, the CST material is still being considered as a potential backup ion-exchanger material. The performance of a proposed backup ion-exchange column using IONSIV IE-911 (CST in its engineered-form) material for the removal of cesium from Hanford high level radioactive alkaline waste is discussed. This report focuses attention on the ion-exchange aspects and addresses the loading phase of the process cycle.
Download or read book SuperLig 639 Equilibrium Sorption Data for Technetium from Hanford Tank written by and published by . This book was released on 2001 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: SuperLig (R) 639 ion exchange resin is currently being evaluated for technetium removal from radioactive Hanford tank wastes. The results indicate that SuperLig (R) 639 resin is highly selective for pertechnetate in the presence of relatively high concentrations of nitrate anion.
Download or read book Technetium Removal from Hanford and Savannah River Site Actual Tank Waste Supernates with SuperLig R 639 Resin written by and published by . This book was released on 2002 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: SuperLig(R) 639 elutable, organic resin has been selected for technetium (as pertechnetate ion) removal from Hanford Site radioactive waste samples as part of the River Protection Project - Waste Treatment Plant (RPP-WTP) design. In support of the RPP-WTP flow sheet development, column tests have been performed at the Savannah River Technology Center with SuperLig(R) 639 resin using actual Hanford Site tank waste samples. The resin was shown to be highly effective at pertechnetate removal from these caustic, high-sodium, aqueous waste samples. Pertechnetate ion was subsequently eluted from the columns with water. An additional column test conducted on a Savannah River Site waste sample revealed exceptional performance, presumably due to the fact that lower concentrations of competing anions (primarily nitrate) were present in the sample.
Download or read book Summary of Testing of SuperLig 639 at the TFL Ion Exchange Facility written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: A pilot scale facility was designed and built in the Thermal Fluids Laboratory at the Savannah River Technology Center to test ion exchange resins for removing technetium and cesium from simulated Hanford Low Activity Waste (LAW). The facility supports the design of the Hanford River Protection Project for BNFL, Inc. The pilot scale system mimics the full-length of the columns and the operational scenario of the planned ion exchange system. Purposes of the testing include confirmation of the design, evaluation of methods for process optimization and developing methods for waste volume minimization. This report documents the performance of the technetium removal resin.
Download or read book Scoping Tests of Technetium and Iodine Removal from Tank Waste Using SuperLig 639 Resin written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary chemical form of 99Tc found in Hanford Low Activity Waste (LAW) is pertechnetate anion (TcO4 - ), which is highly soluble in water, and is mobile if released to the environment. Pertechnetate will not be removed from the aqueous waste in the Hanford waste treatment plant, and the primary disposition path is immobilization in the LAW glass waste form, which will be disposed in the Integrated Disposal Facility (IDF). Due to the soluble properties of pertechnetate, and the potential for impact to the Performance Assessment (PA), effective management of 99Tc is important to the overall success of the River Protection Project mission. Washington River Protection Solutions (WRPS) is developing some conceptual flow-sheets for LAW treatment and disposal that could benefit from technetium removal. While 99Tc is the primary radionuclide of interest, 129I also contributes to the calculated future dose of disposed LAW, and it would be of interest to examine if removal is possible.
Download or read book Intermediate Scale Ion Exchange Removal of Technetium from Savannah River Site Tank 44 F Supernate Solution written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: As part of the Hanford River Protection Project waste Treatment facility design contracted to BNFL, Inc., a sample of Savannah River Site (SRS) Tank 4 F waste solution was treated for the removal of technetium (as pertechnetate ion). Interest in treating the SRS sample for Tc removal resulted from the similarity between the Tank 44 F supernate composition and Hanford Envelope A supernate solutions. The Tank 44 F sample was available as a by-product of tests already conducted at the Savannah River Technology Center (SRTC) as part of the Alternative Salt Disposition Program for treatment of SRS wastes. Testing of the SRS sample resulted in considerable cost-savings since it was not necessary to ship a sample of Hanford supernate to SRS.
Download or read book Intermediate scale Ion Exchange Removal of Cesium and Technetium from Hanford Tank 241 AN 102 written by William D. King and published by . This book was released on 2001 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of Spent Ion Exchange Media written by and published by . This book was released on 2000 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: The current BNFL Inc. flowsheet for the pretreatment of the Hanford High-Level tank wastes includes the use of Superlig{reg_sign} materials for the removal of 137Cs and 99Tc from the aqueous fraction of the waste. The cesium-selective Superlig{reg_sign} 644 (SL-644) and the technetium-selective Superlig{reg_sign} 639 (SL-639) have been evaluated in tests with actual waste samples. These materials have a finite processing lifetime in the plant and will need to be disposed of. The composition and level of residual radionuclide contamination is important for assessing various disposal pathways for the Superlig{reg_sign} materials. This report contains the results of analyses of subsamples of the SL-639 and SL 644 materials that have been used in small column testing of actual waste samples at the Radiochemical Processing Laboratory. The wastes that have been tested include samples from Tanks 241-AW-101 and 241-AN-107. The analyses of the spent resins include inductively coupled plasma/atomic emission spectrometry (ICP-AES) for metals, cold vapor atomic absorption (CVAA) spectroscopy for mercury, gamma energy analysis (GEA) for radionuclides and inductively coupled plasma/mass spectrometry (ICP-MS) for selected metals and radionuclides. While these results provide an indication of the analyte concentrations that may be left on the spent resin, they do not fully represent the concentrations that may be found after extended plant processing with additional load/elute cycles and different waste compositions. BNFL estimates that the SL-644 may last for 100 load/elute cycles with Envelope A and C wastes and 20 cycles with Envelope B wastes. The number of useable load/elute cycles for the SL-639 is not well defined, but is likely on the order of hundreds.
