Download or read book Assessment of Commercially Available Ion Exchange Materials for Cesium Removal from Highly Alkaline Wastes written by and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Initial Evaluation of Two Organic Resins and Their Ion Exchange Column Performance for the Recovery of Cesium from Hanford Alkaline Wastes written by Lane A. Bray and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Alternatives for High Level Waste Salt Processing at the Savannah River Site written by National Research Council and published by National Academies Press. This book was released on 2000-11-30 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Second World War introduced the world to nuclear weapons and their consequences. Behind the scene of these nuclear weapons and an aspect of their consequences is radioactive waste. Radioactive waste has varying degrees of harmfulness and poses a problem when it comes to storage and disposal. Radioactive waste is usually kept below ground in varying containers, which depend on how radioactive the waste it. High-level radioactive waste (HLW) can be stored in underground carbon-steel tanks. However, radioactive waste must also be further immobilized to ensure our safety. There are several sites in the United States where high-level radioactive waste (HLW) are stored; including the Savannah River Site (SRS), established in 1950 to produce plutonium and tritium isotopes for defense purposes. In order to further immobilize the radioactive waste at this site an in-tank precipitation (ITP) process is utilized. Through this method, the sludge portion of the tank wastes is being removed and immobilized in borosilicate glass for eventual disposal in a geological repository. As a result, a highly alkaline salt, present in both liquid and solid forms, is produced. The salt contains cesium, strontium, actinides such as plutonium and neptunium, and other radionuclides. But is this the best method? The National Research Council (NRC) has empanelled a committee, at the request of the U.S. Department of Energy (DOE), to provide an independent technical review of alternatives to the discontinued in-tank precipitation (ITP) process for treating the HLW stored in tanks at the SRS. Alternatives for High-Level Waste Salt Processing at the Savannah RIver Site summarizes the finding of the committee which sought to answer 4 questions including: "Was an appropriately comprehensive set of cesium partitioning alternatives identified and are there other alternatives that should be explored?" and "Are there significant barriers to the implementation of any of the preferred alternatives, taking into account their state of development and their ability to be integrated into the existing SRS HLW system?"

Download or read book ION EXCHANGE MODELING FOR REMOVAL OF CESIUM FROM HANFORD WASTE USING SUPERLIG 644 RESIN written by L. Hamm and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The expected performance of a proposed ion exchange column using SuperLig{reg_sign} 644 resin for the removal of cesium from Hanford high level radioactive alkaline waste is discussed. This report represents a final report on the ability and knowledge with regard to modeling the Cesium-SuperLig{reg_sign} 644 resin ion exchange system. Only the loading phase of the cycle process is addressed within this report. Pertinent bench-scale column tests and batch equilibrium experiments are addressed. The methodology employed and sensitivity analyses are also included (i.e., existing methodology employed is referenced to prior developmental efforts while updated methodology is discussed). Pilot-scale testing is not assessed since no pilot-scale testing was available at the time of this report. Column performance predictions are made considering three selected feed compositions under nominal operating conditions. The sensitivity analyses provided help to identify key parameters that aid in resin procurement acceptance criteria. The methodology and application presented within this report reflect the expected behavior of SuperLig{reg_sign} 644 resin manufactured at the production-scale (i.e, 250 gallon batch size level). The primary objective of this work was, through modeling and verification based on experimental assessments, to predict the cesium removal performance of SuperLig{reg_sign} 644 resin for application in the RPP pretreatment facility.

Download or read book Development of a Continuous Ion Exchange Process for the Removal and Recovery of High purity Cesium from Alkaline Waste written by I. R. Higgins and published by . This book was released on 1958 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Testing a New Cesium specific Ion Exchange Resin for Decontamination of Alkaline High activity Waste written by and published by . This book was released on 1989 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radioactive Cs-137 is a fission produce found in wastes produced by reprocessing fuels from nuclear reactors. The highest concentrations of this isotope in wastes from the reprocessing of defense production reactors are found in the alkaline high-activity waste, a mixture primarily of sodium nitrate and sodium hydroxide called the supernate. In recent years, much research has been directed at methods for the selective removal and concentration of Cs-137 during waste processing. The approach to the ultimate management of high-activity waste at the Savannah River Site (SRS) is to remove cesium from the supernate, combine it with insoluble sludge formed on neutralization of acidic waste, and convert them both to glass by vitrification in a joule heater melter. A cesium-specific ion exchange resin that will adequately decontaminate the supernate but will not introduce excessive amounts of organic material into the melter has been developed at SRS. The resin has been tested with simulated, both at SRS and at Battelle's Pacific Northwest Lab, and with actual supernate at SRS. It has consistently shown reliable performance and high selectivity than other organic ion exchangers for cesium ion in those solutions. Repeated cycles on 200 mL. columns using simulated supernate feed and formic acid eluent have established operation parameters for the resin.

Download or read book Cesium Removal Using Crystalline Silicotitanate Innovative Technology Summary Report written by and published by . This book was released on 1999 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: Approximately 100 million gallons of radioactive waste is stored in underground storage tanks at the Hanford Site, Idaho National Engineering and Environmental Laboratory (INEEL), Oak Ridge Reservation, and Savannah River Site (SRS). Most of the radioactivity comes from 137Cs, which emits high-activity gamma radiation. The Cesium Removal System is a modular, transportable, ion-exchange system configured as a compact processing unit. Liquid tank waste flows through columns packed with solid material, called a sorbent, that selectively adsorbs cesium and allows the other materials to pass through. The sorbent is crystalline silicotitanate (CST), an engineered material with a high capacity for sorbing cesium from alkaline wastes. The Cesium Removal System was demonstrated at Oak Ridge using Melton Valley Storage Tank (MVST) waste for feed. Demonstration operations began in September 1996 and were completed during June 1997. Prior to the demonstration, a number of ion-exchange materials were evaluated at Oak Ridge with MVST waste. Also, three ion-exchange materials and three waste types were tested at Hanford. These bench-scale tests were conducted in a hot cell. Hanford's results showed that 300 times less sorbent was used by selecting Ionsiv IE-911 over organic ion-exchange resins for cesium removal. This paper gives a description of the technology and discusses its performance, applications, cost, regulatory and policy issues and lessons learned.

Download or read book Ion Exchange Pretreatment of Alkaline Radwaste for Cesium Removal written by and published by . This book was released on 1994 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: A cation exchange resin has been tested for its ability to remove the Cs ion from simulants of highly alkaline liquid nuclear wastes found at the Savannah River Site, Oak Ridge, and Hanford. The resin is a condensation polymer of the K salt of resorcinol and formaldehyde. It removes milli- and micromolar amounts of Cs from solutions that contain as high as 11 molar Na. Small column tests indicate that approximately 200 column volumes of SRS simulant and 205 column volumes of OR Tank 25 supernatant simulant can be processed before the resin requires regeneration. For these two wastes, a carousel arrangement of two columns in series and a third in reserve can be used effectively in a process. Hanford 101-AW simulant generates a less sharp breakthrough profile with this resin, though an operation using a maximum of three columns in series with another column off-line for regeneration would be effective if the resin beds are allowed to reach about 90% breakthrough before taking them out of service. Parameters that effect the performance of the resin with a particular feed solution are the concentrations of the two primary ions of interest, Cs+ and Na+, as well as the concentrations of K+ and OH−. A further ramification of the hydroxide ion concentration is its role in assisting oxidation of the resin, thereby destroying its usefulness in cesium removal. Although the performance of the resin is unaffected at doses of 1 E+8 rad ionizing radiation, it shows noticeable degradation after storage for 100 hours in alkaline solutions, generating quinone and ketone groups, as determined from C-13 NMR and by an increase in total organic C content of the contacting solution. Gases detected from the radiolysis of the resin/simulant mixture are CO2 from the resin, N2O from nitrate in the simulant, and H2 possibly from resin and simulant. Oxygen depletion in the mixture results from radiolysis and chemical degradation.

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 The Office of Environmental Management Technical Reports written by and published by . This book was released on 1997 with total page 972 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radioactive Waste Management written by and published by . This book was released on 1981 with total page 726 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ijj n m be sifr t hat talm d written by Ezra Zion Melamed and published by . This book was released on 1986 with total page 449 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Recent Developments in Ion Exchange written by Peter A. Williams and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: These Conference Proceedings deal with the papers presented at the International Conference on Ion Exchange Processes (ION-EX '90) which was held at The North East Wales Institute of Higher Education, 9- 11 July 1990. The camera-ready paper format was chosen so that delegates could receive their copy on arrival at the Conference. The Proceedings include reviews of biological materials, inorganic ion exchangers, the nuclear industry, theoretical aspects and new advances. In addition, there are research papers dealing with industrial ion exchange procedures and new materials. The Proceedings should therefore be of interest to those who need to be brought up to date in the various aspects of processes which involve ion exchange and ion chromatography which are now accepted as important in analysis, separation processes and process control. In each of these areas there have been important developments which are herein described. As Editors we should like to express our thanks to the individual authors for preparing their manuscripts in the required format and to Haydn Hughes and Linda Sneddon for their invaluable assistance in compiling these Proceedings. PETER A. WILLIAMS MICHAEL J. HUDSON V\1 CONTENTS v Preface Part 1: Biological Materials The Importance of Ion Exchange Processes in Living Systems 3 R. J. P. Williams The Use of Chemically Suppressed Ion Chromatography in Elemental Analysis 17 J. P. Senior Biological Separations Using Latex-Based Pellicular Resins 23 K.

Download or read book Evaluation and Comparison of SuperLig reg sign 644 Resorcinol formaldehyde and CS 100 Ion Exchange Materials for the Removal of Cesium from Simulated Alkaline Supernate written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: PNL evaluated three polymeric materials for Cs removal efficiency from a simulated Hanford Neutralized Current Acid Waste (NCAW) supernatant liquid using 200 mL ion exchange columns. Cs loadings (mmole Cs/g resin) were 0.20, 0.18, and 0.039 for Super Lig 644, R-F, and CS-100 (0.045, 0.070, 0.011 mmole Cs/mL resin). Elution of each resin material with 0.5 M HNO[sub 3] required 3.5, 7.0, and 3.2 cv to reach 0.1 C/C[sub 0] for the respective materials, resulting in volume compressions of 27, 20, and 6.9. Peak Cs concentrations during elution was 185, 38.5, and 27.8 C/C[sub 0]. SuperLig 644 had the highest Cs loading per gram in NCAW and the greatest volume compression on aci elution. Because of high density and poor elution, R-F had the highest Cs loading per unit volume and lower volume compression. CS-100, the baseline material for Cs removal at Hanford, was inferior to both SuperLig 644 and R-F in terms of Cs loading and selectivity over sodium.

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 Performance of Crystalline Silicotitanates for Cesium Removal from Hanford Tank Waste Simulants written by and published by . This book was released on 1994 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new class of inorganic ion exchangers, called crystalline silicotitanates (CSTs), has been prepared at Sandia National Laboratories and Texas A & M University. CSTs have been determined to have high selectivity for the adsorption of Cs and Sr, and several other radionuclides from highly alkaline, high-sodium supernate solutions such as those found at Westinghouse Hanford (WHC). Continuous flow, ion-exchange columns are expected to be used to remove Cs and other radionuclides from the Hanford tank supernate. The proposed application for the CST would be Cs removal from highly alkaline salt solutions in a single pass process with interim storage of the Cs loaded CST until the glass vitrification plant is operational. This paper presents test results which address material requirements relevant for Hanford radwaste processing. This paper also discusses the integrated experimental and modeling approach being developed to establish the performance of the CST materials for the range of solution compositions and processing conditions which are expected to occur. The status on the commercialization of the CST material is also discussed.

Download or read book Evaluation of Crystalline Silicotitanate and Self Assembled Monolayers on Mesoporous Support for Cesium and Mercury Removal from DWPF Recycle written by and published by . This book was released on 1999 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The affinities for cesium and mercury ions contained in DWPF recycle simulants and Tank-22H waste have been evaluated using Crystalline Silicotitanate (CST) and Self-Assembled Monolayers on Mesoporous Support (SAMMS) ion-exchange materials, respectively. Results of the performance evaluations of CST on the uptake of cesium with simulants and actual DWPF recycle samples (Tank 22H) indicate that, in practice, this inorganic ion-exchange material can be used to remove radioactive cesium from the DWPF recycle. SAMMS material showed little or no affinity for mercury from highly alkaline DWPF waste. However, at near neutral conditions (DWPF simulant solution pH adjusted to 7), SAMMS was found to have a significant affinity for mercury. Conventional Duolite/256 ion exchange material showed an increase in affinity for mercury with increase in DWPF recycle simulant pH. Duolite/256 GT-73 also had a high batch distribution coefficient for mercury uptake from actual Tank 22H waste.