Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Application Of Multi Group Diffusion Theory To Mechanistic Modelling Of Leaching Behavior Of Solidified Low Level Radioactive Waste Forms
Download Application Of Multi Group Diffusion Theory To Mechanistic Modelling Of Leaching Behavior Of Solidified Low Level Radioactive Waste Forms full books in PDF, epub, and Kindle. Read online Application Of Multi Group Diffusion Theory To Mechanistic Modelling Of Leaching Behavior Of Solidified Low Level Radioactive Waste Forms ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis APPLICATION OF MULTI-GROUP DIFFUSION THEORY TO MECHANISTIC MODELLING OF LEACHING BEHAVIOR OF SOLIDIFIED LOW-LEVEL RADIOACTIVE WASTE FORMS. by : Somkid Nimnual
Download or read book APPLICATION OF MULTI-GROUP DIFFUSION THEORY TO MECHANISTIC MODELLING OF LEACHING BEHAVIOR OF SOLIDIFIED LOW-LEVEL RADIOACTIVE WASTE FORMS. written by Somkid Nimnual and published by . This book was released on 1987 with total page 0 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 1988 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Leaching Mechanisms of Solidified Low-level Waste. The Literature Survey by :
Download or read book Leaching Mechanisms of Solidified Low-level Waste. The Literature Survey written by and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A literature survey on leaching mechanisms, available mathematical models and factors that affect leaching from solidified low-level radioactive waste (LLW) was compiled. Physicochemical mechanisms identified include diffusion, dissolution, ion exchange, corrosion and surface effects. Diffusion was generally considered to be the predominant mechanism in LLW leachability. However, this hierarchy of importance has been strongly questioned for waste forms containing soluble salts and has been shown to be invalid for waste forms incorporating sorbents which control the release of radionuclides by ion exchange. Leaching behavior was modeled both mathematically for curve fitting to leaching data and by consideration of physical and chemical interactions within and between solidification agents, waste materials and additives, if any. Physicochemical analyses of bitumen and polymer solidification agents have considered them to be inert encapsulants with limited water permeability. All of the mathematical models are derived from solutions to the diffusion equation. Other mechanistic processes are included as additional terms in the equation. No comprehensive evaluations of mathematical models for LLW based on curve fitting to data were found in the literature. Factors that affect leaching have been categorized as system factors, leachant factors and waste form factors. System factors include temperature, pressure, radiation, time and the ratio of waste form area to leachant volume. Leachant factors include pH, Eh, flow or replacement frequency and composition while waste form factors include composition, surface condition, porosity and surface area to volume ratio. Information from the literature is reported for each of these factors. 75 refs., 2 figs., 4 tabs.
Book Synopsis A Mechanistic Model for Leaching from Low-level Radioactive Waste Packages by :
Download or read book A Mechanistic Model for Leaching from Low-level Radioactive Waste Packages written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of a waste leaching model to predict radionuclide releases from porous wastes in corrodible outer containers in unsaturated conditions and/or conditions of intermittent water flow is summarized in this paper. Three major processes have been conceptualized as necessarily participating in waste leaching: infiltration of water to the waste package; interaction of this water with the waste; and exit of radionuclide-laden water from the waste package. Through the exit point, the main features of the whole leaching process are held in common. The departure occurs in two main ways: 1) the method of entrance of the radionuclides to leachant (i.e., part of the waste-water interaction phase outlined earlier); and 2) the mode of exit from the waste form/waste package (i.e., the exit of radionuclide-laden water phase). The first branching point, which occurs in relation to 1), leads to either readily soluble species directly entering leachant on contact, or to other processes)emdash) mainly expected to be diffusion, dissolution or ion exchange, or some combination thereof. All of these latter processes will be slow compared to the first branch (ready solubilization). The modeling work presented here concentrates on early releases due to the accessing and solubilization readily available radionuclides (i.e., the waste-water interaction phase has been discussed for accessible, soluble species). The exit mode phase, 2) above, has been divided into a rinsing mechanism and a diffusion mechanism. Results of each of the modeled exit mechanisms are presented and discussed. 20 refs., 9 figs., 2 tabs.
Book Synopsis Dissertation Abstracts International by :
Download or read book Dissertation Abstracts International written by and published by . This book was released on 1987 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Index to American Doctoral Dissertations by :
Download or read book Index to American Doctoral Dissertations written by and published by . This book was released on 1986 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Comprehensive Dissertation Index by :
Download or read book Comprehensive Dissertation Index written by and published by . This book was released on 1989 with total page 1116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis A Mechanistic Model for Leaching from Low-level Radioactive Waste Packages by :
Download or read book A Mechanistic Model for Leaching from Low-level Radioactive Waste Packages written by and published by . This book was released on 1988 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Leaching Studies of Low-level Radioactive Waste Forms by :
Download or read book Leaching Studies of Low-level Radioactive Waste Forms written by and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A research program has been under way at the Brookhaven National Laboratory to investigate the radionuclide release behavior of ion exchange bead resin waste solidified in Portland cement. An important aspect of this program is to develop and evaluate testing procedures and methodologies which enable the long-term performance evaluation of waste forms under simulated field conditions. Cesium and strontium release behavior using a range of testing procedures, including intermittent leachant flow conditions, has been investigated. For cyclic wet/dry leaching tests, extended dry periods tend to enhance the release of Cs and suppress the release of Sr. Under extended wet period leaching conditions, however, both Cs and Sr exhibit suppressed releases. In contrast, radionuclide releases observed under continuously saturated leaching conditions, as represented by conventional leaching tests, are significantly different. The relevance and aplicability of these laboratory data obtained under a wide range of leaching conditions to the performance evaluation of waste forms under anticipated field conditions is discussed. 12 refs., 9 figs., 3 tabs.
Book Synopsis An Experimental Survey of the Factors that Affect Leaching from Low-level Radioactive Waste Forms by :
Download or read book An Experimental Survey of the Factors that Affect Leaching from Low-level Radioactive Waste Forms written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This report represents the results of an experimental survey of the factors that affect leaching from several types of solidified low-level radioactive waste forms. The goal of these investigations was to determine those factors that accelerate leaching without changing its mechanism(s). Typically, although not in every case, the accelerating factors include: increased temperature, increased waste loading (i.e., increased waste to binder ratio), and decreased size (i.e., decreased waste form volume to surface area ratio). Additional factors that were studied were: increased leachant volume to waste form surface area ratio, pH, leachant composition (groundwaters, natural and synthetic chelating agents), leachant flow rate or replacement frequency and waste form porosity and surface condition. Other potential factors, including the radiation environment and pressure, were omitted based on a survey of the literature. 82 refs., 236 figs., 13 tabs.
Download or read book INIS Atomindex written by and published by . This book was released on 1988 with total page 988 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Optimization of the Factors that Accelerate Leaching by :
Download or read book Optimization of the Factors that Accelerate Leaching written by and published by . This book was released on 1989 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: The prediction of long-term leachability of low-level radioactive waste forms is an essential element of disposal-site performance assessment. This report describes experiments and modeling techniques used to develop an accelerated leach test that meets this need. The acceleration in leaching rates caused by the combinations of two or more factors were experimentally determined. These factors were identified earlier as being able to individually accelerate leaching. They are: elevated temperature, the size of the waste form, the ratio of the volume of leachant to the surface area of the waste form, and the frequency of replacement of the leachant. The solidification agents employed were ones that are currently used to treat low-level radioactive wastes, namely portland type I cement, bitumen, and vinyl ester-styrene. The simulated wastes, sodium sulfate, sodium tetraborate, and incinerator ash, are simplified representatives of typical low-level waste streams. Experiments determined the leaching behavior of the radionuclides of cesium (Cs-137), strontium (Sr-85), and cobalt (Co-60 or Co-57) from several different formulations of solidification agents and waste types. Leaching results were based upon radiochemical and elemental analyses of aliquots of the leachate, and on its total alkalinity and pH at various times during the experiment (up to 120 days). Solid phase analyses were carried out by Scanning/Electron Microscopy and Energy Dispersive Spectroscopy on the waste forms before and after some leaching experiments. 43 refs., 96 figs., 16 tabs.
Book Synopsis The Effects of Temperature on the Leaching Behavior of Cement Waste Forms by :
Download or read book The Effects of Temperature on the Leaching Behavior of Cement Waste Forms written by and published by . This book was released on 1989 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The leaching mechanisms of simulated low-level radioactive waste forms are being determined as support for development of an accelerated leach test. Two approaches are being used: (1) comparisons of leaching data with results of a model that describes diffusion from a finite cylinder, and (2) observation of the leaching process at temperatures between 20°C and 65°C. To provide results that can be used for modeling, leaching at elevated temperatures must change neither the leaching mechanism nor the structural controls of leaching such as the porosity. Releases of 137Cs, 85Sr, calcium, sodium and potassium from portland cement containing sodium sulfate, as a simulated evaporator sludge, have been determined under a variety of experimental conditions. Data from the leach tests were compared to model results for diffusion from the finite cylinder. While most leaching appears to be diffusion controlled, notable exceptions occur. For all samples activation energies ranging between 6 and 11 Kcal/mole have been calculated from the relationship of the effective diffusion coefficient to increasing temperature, close to the expected value of 5 Kcal/mole for diffusion. 11 refs., 4 figs., 2 tabs.
Book Synopsis Mechanistic Modeling of Nuclear Waste Form Leaching by Aqueous Solutions by : Claudio Pescatore
Download or read book Mechanistic Modeling of Nuclear Waste Form Leaching by Aqueous Solutions written by Claudio Pescatore and published by . This book was released on 1983 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis An Experimental Survey of the Factors that Affect Leaching from Low-level Radioactive Waste Forms by : D. Dougherty
Download or read book An Experimental Survey of the Factors that Affect Leaching from Low-level Radioactive Waste Forms written by D. Dougherty and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis A Comparison of Solidification Media for the Stabilization of Low-level Radioactive Wastes by : M. G. Cowgill
Download or read book A Comparison of Solidification Media for the Stabilization of Low-level Radioactive Wastes written by M. G. Cowgill and published by . This book was released on 1991 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Mechanistic modeling of nuclear waste form leaching by aqueous solutions/ Claudio Pescatore by : Claudio Pescatore
Download or read book Mechanistic modeling of nuclear waste form leaching by aqueous solutions/ Claudio Pescatore written by Claudio Pescatore and published by . This book was released on 1985 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
