Colloidal Agglomerates in Tank Sludge and Their Impact on Waste Processing

1999 ◽  
Vol 556 ◽  
Author(s):  
J. M. Tingey ◽  
B. C. Bunker ◽  
G. L. Graff ◽  
K. D. Keeper ◽  
A. S. Lea ◽  
...  

AbstractDisposal of millions of gallons of existing radioactive wastes in underground storage tanks is a major remediation activity for the United States Department of Energy. These wastes include a substantial volume of insoluble sludges consisting of submicron colloidal particles. Processing these sludges under the proposed processing conditions presents unique challenges in retrieval transport, separation, and solidification of these waste streams. Depending on processing conditions, these colloidal particles can form agglomerated networks having high viscosities that could clog transfer lines or produce high volumes of low-density sediments that interfere with solid-liquid separations. Under different conditions, these particles can be dispersed to form very fine suspended particles that do not settle. Given the wide range of waste chemistries present at Department of Energy sites, it is impractical to measure the properties of all treatment procedures. Under the current research activities, the underlying principles of colloid chemistry and physics are being studied to predict and eventually control the physical properties of sludge suspensions and sediment layers in tank wastes and other waste processing streams. Proposed tank processing strategies include retrieval transport, and solid-liquid separations in basic (pH 10 to 14), high ionic strength (0.1 to 1.0 M) salt solutions. The effect of salt concentration, ionic strength, and salt composition on the physical properties such as viscosity, agglomerate size, and sedimentation of model suspensions containing mixtures of one or two of the major components found in actual wastes have been measured to understand how agglomeration influences processing. Property models developed from theory and experiment on these simple suspensions are then applied to explain the results obtained on actual wastes.

1997 ◽  
Vol 492 ◽  
Author(s):  
W. D. Wilson ◽  
C. M. Schaldach

ABSTRACTWe present a method for the calculation of the binding and rotational energies of neutral (H2S) and charged (HS-) molecules impinging upon a charged (Cu <100>) surface in the presence of an electrolyte. A molecular surface is constructed surrounding the H2S and HS- molecules forming boundary elements. A coupled Schrödinger-Poisson-Boltzmann iterative procedure treats the electronic structure of the molecules at the 6–31G**/MP2 level of theory and includes solvation effects through the single and double layers of charge induced by the electronic distribution. The molecule, together with its charged layers, forms a Molecular Single and Double Layer (MSDL), an object which then interacts with a Gouy-Chapman plane within the electrolyte. The additional induced charge at the molecular surface resulting from this electric field is obtained by solving a second set of boundary element equations. Repulsive interactions between the atoms of the molecule and those of the surface are obtained using a rigid-ion Hartree-Fock method. Binding energies of the molecule to the surface are determined as a function of the real surface charge imposed and also the ionic strength of the solution. It is found that surface charges can completely (180°) reorient these molecules and that the counterions in the solution can completely screen binding effects of even large surface charges.Work supported by the United States Department of Energy under contract #DE-AC04–94AL85000.


2006 ◽  
Vol 930 ◽  
Author(s):  
Robert W. Bradshaw ◽  
Blake A. Simmons ◽  
Eric H Majzoub ◽  
W. Miles Clift ◽  
Daniel E. Dedrick

ABSTRACTClathrate hydrates are crystalline inclusion compounds of water and a guest molecule (e.g., methane) that form at temperatures below ambient but above the freezing point of water. There are three known crystalline structures of hydrates (structure I, II, and H) in which cavities within the hydrogen bonded water molecule lattice trap the hydrate-forming species. The clathrate structure excludes dissolved solutes, such as sodium chloride, from the aqueous phase and thereby offers a possible means to produce potable water from seawater or brackish water. The concept of using clathrate hydrates for desalination is not new. However, before clathrate hydrate desalination becomes a viable technology, fundamental issues of controlled hydrate formation, hydrate size and morphology, agglomeration, amount of entrapped salt, and the efficient recovery of hydrates must be understood. This paper will report structural characterization of hydrates formed with several guest molecules over a wide range of conditions in an attempt to further the physicochemical insight needed to address these issues.Clathrate hydrate formation experiments were performed using a variety of host molecules, including R141b, a commercial refrigerant, C2FCl2H3. Hydrates of R141b were formed at temperatures from 2°C to 6°C and atmospheric pressure from deionized water and 2% - 7% NaCl solutions. Samples of the hydrates were characterized by cold-stage x-ray diffraction and Raman spectroscopy and determined to be structure II. Additional experiments were conducted with a gaseous hydrate former, ethylene, which readily formed hydrates with deionized or saline water at 2°C and several atmospheres of pressure. Experiments with several other hydrate forming molecules were conducted and the results obtained from their structural characterization will be reported. We will also present proof-of-concept experiments demonstrating a novel technique of desalination using these hydrate formers.Sandia National Laboratories is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin company, for the United States Department of Energy under contract DE-AC04-94AL85000.


2021 ◽  
Vol 12 (3) ◽  
pp. 90
Author(s):  
Ehsan Sabri Islam ◽  
Shabbir Ahmed ◽  
Aymeric Rousseau

The U.S. Department of Energy’s Vehicle Technologies Office (VTO) supports research, development, and deployment of efficient, sustainable transportation technologies that will improve energy efficiency and fuel economy, and enable America to use less petroleum. To accelerate the development and adoption of new technologies, VTO has developed specific targets for a wide range of powertrain components, including the energy storage system. In this study, we use Autonomie, Argonne National Laboratory’s (Argonne’s) vehicle system simulation tool to evaluate future energy storage requirements (power, energy, etc.) for different vehicle classes, powertrains, component technologies and timeframes. BatPac, Argonne’s tool dedicated to energy storage pack design and costs, is then used to quantify the materials required for each pack. Market penetrations are then used to estimate the overall material demand worldwide and in the United States, with or without recycling. The results demonstrate that the positive impact of VTO research and development will lead to significant reduction in material compared to business-as-usual due to new anode and cathode designs, along with acceleration in battery cell chemistry penetrations. In terms of material demands, it is observed that lithium demand reaches about 80,000 tons (by a factor of 42–45), nickel demand reaches about 500,000 tons (by a factor of 47–56), manganese demand reaches about 30,000–50,000 tons (by a factor of 20–34), and cobalt demand reaches about 30,000 tons (by a factor of 13–28) in the future by 2050. The individual material demand per unit energy, however, decreases significantly in the future due to advances in VTO research and development activities. The increase in battery material demands is mostly driven by increased electrified vehicle fleet penetration in the markets.


TAPPI Journal ◽  
2016 ◽  
Vol 15 (5) ◽  
pp. 331-335 ◽  
Author(s):  
LEBO XU ◽  
JEREMY MYERS ◽  
PETER HART

Retention of cationic dispersed rosin size was studied via turbidity measurements on stock filtrate with different alum and dispersed rosin size dosages. Stock charge characteristics were analyzed using both an analysis of charge demand determined via a streaming current detector and an evaluation of zeta potential of the fibers by streaming potential measurement. The results indicated that an optimum amount of alum existed such that good sizing retention was maintained throughout a wide range of dispersed rosin size dosages. However, when an excessive amount of alum was used and fines and colloidal particles were transitioned from anionic to cationic, the cationic size retention was reduced. Laboratory results were confirmed with a paper machine trial. All data suggested that a stock charge study was necessary to identify optimal alum dosage for a cationic dispersed rosin sizing program.


Author(s):  
Tim Rutherford-Johnson

By the start of the 21st century many of the foundations of postwar culture had disappeared: Europe had been rebuilt and, as the EU, had become one of the world’s largest economies; the United States’ claim to global dominance was threatened; and the postwar social democratic consensus was being replaced by market-led neoliberalism. Most importantly of all, the Cold War was over, and the World Wide Web had been born. Music After The Fall considers contemporary musical composition against this changed backdrop, placing it in the context of globalization, digitization, and new media. Drawing on theories from the other arts, in particular art and architecture, it expands the definition of Western art music to include forms of composition, experimental music, sound art, and crossover work from across the spectrum, inside and beyond the concert hall. Each chapter considers a wide range of composers, performers, works, and institutions are considered critically to build up a broad and rich picture of the new music ecosystem, from North American string quartets to Lebanese improvisers, from South American electroacoustic studios to pianos in the Australian outback. A new approach to the study of contemporary music is developed that relies less on taxonomies of style and technique, and more on the comparison of different responses to common themes, among them permission, fluidity, excess, and loss.


Author(s):  
Kathryn A. Sloan

Popular culture has long conflated Mexico with the macabre. Some persuasive intellectuals argue that Mexicans have a special relationship with death, formed in the crucible of their hybrid Aztec-European heritage. Death is their intimate friend; death is mocked and accepted with irony and fatalistic abandon. The commonplace nature of death desensitizes Mexicans to suffering. Death, simply put, defines Mexico. There must have been historical actors who looked away from human misery, but to essentialize a diverse group of people as possessing a unique death cult delights those who want to see the exotic in Mexico or distinguish that society from its peers. Examining tragic and untimely death—namely self-annihilation—reveals a counter narrative. What could be more chilling than suicide, especially the violent death of the young? What desperation or madness pushed the victim to raise the gun to the temple or slip the noose around the neck? A close examination of a wide range of twentieth-century historical documents proves that Mexicans did not accept death with a cavalier chuckle nor develop a unique death cult, for that matter. Quite the reverse, Mexicans behaved just as their contemporaries did in Austria, France, England, and the United States. They devoted scientific inquiry to the malady and mourned the loss of each life to suicide.


Author(s):  
David Vogel

This book examines the politics of consumer and environmental risk regulation in the United States and Europe over the last five decades, explaining why America and Europe have often regulated a wide range of similar risks differently. It finds that between 1960 and 1990, American health, safety, and environmental regulations were more stringent, risk averse, comprehensive, and innovative than those adopted in Europe. But since around 1990 global regulatory leadership has shifted to Europe. What explains this striking reversal? This book takes an in-depth, comparative look at European and American policies toward a range of consumer and environmental risks, including vehicle air pollution, ozone depletion, climate change, beef and milk hormones, genetically modified agriculture, antibiotics in animal feed, pesticides, cosmetic safety, and hazardous substances in electronic products. The book traces how concerns over such risks—and pressure on political leaders to do something about them—have risen among the European public but declined among Americans. The book explores how policymakers in Europe have grown supportive of more stringent regulations while those in the United States have become sharply polarized along partisan lines. And as European policymakers have grown more willing to regulate risks on precautionary grounds, increasingly skeptical American policymakers have called for higher levels of scientific certainty before imposing additional regulatory controls on business.


Alloy Digest ◽  
1982 ◽  
Vol 31 (8) ◽  

Abstract ANACONDA Alloy 268 is a copper-zinc alloy with excellent cold-working properties; it can be cold worked by all the conventional fabrication processes. Its corrosion resistance is excellent-to-good in most environments. This alloy has a wide range of applications including items such as springs, bathroom fixtures, automotive radiators, lamp sockets and sanitary traps. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fatigue. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Cu-442. Producer or source: Anaconda American Brass Company.


Alloy Digest ◽  
1981 ◽  
Vol 30 (8) ◽  

Abstract CENTRI-CAST GRAY IRON 50 is a centrifugally cast gray iron with a nominal tensile strength of 50,000 psi. It is cast in the form of tubing which has a wide range of uses in applications where size and shape are of paramount importance and freedom from pattern cost is an important consideration. Among its many applications are farm machinery, seals, bushings, machine tools and general machinery uses. This datasheet provides information on composition, physical properties, microstructure, hardness, elasticity, tensile properties, and compressive and shear strength as well as fatigue. It also includes information on casting, heat treating, machining, and surface treatment. Filing Code: CI-51. Producer or source: Federal Bronze Products Inc..


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