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Cooperative Research Program in Coal-Waste Liquefaction
The results of a feasibility study for a demonstration plant for the liquefaction of waste plastic and tires and the coprocessing of these waste polymers with coal are presented. The study was conducted by a committee that included nine representatives from the CFFS, six from the U.S. Department of Energy - Federal Energy Technology Center (FETC), and four from Burns and Roe, Inc. The study included: (1) An assessment of current recycling practices, particularly feedstock recycling in Germany; (2) A review of pertinent research, and a survey of feedstock availability for various types of waste polymers; and (3) A conceptual design for a demonstration plant was developed and an economic analysis for various feedstock mixes. The base case for feedstock scenarios was chosen to be 200 tons per day of waste plastic and 100 tons per day of waste tires. For this base case with oil priced at $20 per barrel, the return on investment (ROI) was found to range from 9% to 20%, using tipping fees for waste plastic and tires typical of those existing in the U.S. The most profitable feedstock appeared to waste plastic alone, with a plant processing 300 t/d of plastic yielding ROI's from 13 …
Date:
March 31, 2000
Creator:
Huffman, Gerald
Object Type:
Report
System:
The UNT Digital Library
Texas Jewish Post (Fort Worth, Tex.), Vol. 54, No. 35, Ed. 1 Thursday, August 31, 2000
Weekly Jewish newspaper from Fort Worth, Texas that includes local, state, and national news along with extensive advertising.
Date:
August 31, 2000
Creator:
Wisch, J. A. & Wisch, Rene
Object Type:
Newspaper
System:
The Portal to Texas History
Seminole Sentinel (Seminole, Tex.), Vol. 93, No. 65, Ed. 1 Wednesday, May 31, 2000
Semiweekly newspaper from Seminole, Texas that includes local, state, and national news along with advertising.
Date:
May 31, 2000
Creator:
Dow, M. Gene & Fisher, David
Object Type:
Newspaper
System:
The Portal to Texas History
Hondo Anvil Herald (Hondo, Tex.), Vol. 114, No. 35, Ed. 1 Thursday, August 31, 2000
Weekly newspaper from Hondo, Texas that includes local, state, and national news along with extensive advertising.
Date:
August 31, 2000
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History
Archer County News (Archer City, Tex.), No. 35, Ed. 1 Thursday, August 31, 2000
Weekly newspaper from Archer City, Texas that includes local, state, and national news along with advertising.
Date:
August 31, 2000
Creator:
Lewis, Shelley
Object Type:
Newspaper
System:
The Portal to Texas History
SEQUENCE STRATIGRAPHIC ANALYSIS AND FACIES ARCHITECTURE OF THE CRETACEOUS MANCOS SHALE ON AND NEAR THE JICARILLA APACHE INDIAN RESERVATION, NEW MEXICO-THEIR RELATION TO SITES OF OIL ACCUMULATION
Oil distribution in the lower part of the Mancos Shale seems to be mainly controlled by fractures and by sandier facies that are dolomite-cemented. Structure in the area of the Jicarilla Apache Indian Reservation consists of the broad northwest- to southeast-trending Chaco slope, the deep central basin, and the monocline that forms the eastern boundary of the San Juan Basin. Superimposed on the regional structure are broad low-amplitude folds. Fractures seem best developed in the areas of these folds. Using sequence stratigraphic principals, the lower part of the Mancos Shale has been subdivided into four main regressive and transgressive components. These include facies that are the basinal time equivalents to the Gallup Sandstone, an overlying interbedded sandstone and shale sequence time equivalent to the transgressive Mulatto Tongue of the Mancos Shale, the El Vado Sandstone Member which is time equivalent to part of the Dalton Sandstone, and an unnamed interbedded sandstone and shale succession time equivalent to the regressive Dalton Sandstone and transgressive Hosta Tongue of the Mesaverde Group. Facies time equivalent to the Gallup Sandstone underlie an unconformity of regional extent. These facies are gradually truncated from south to north across the Reservation. The best potential for additional oil …
Date:
March 31, 2000
Creator:
Ridgley, Jennie
Object Type:
Report
System:
The UNT Digital Library
Phase Equilibria Modification by Electric Fields
This project has been focused on equilibrium and transport properties of gas-liquid, liquid-liquid, and solid-liquid systems under electric fields. The objective was to intensify separations methods that are used or can be used to process liquid waste or contaminated groundwater within DOE sites. Examples of processes that have been investigated are distillation (gas-liquid), extraction (liquid-liquid), and sorption (solid-liquid). Effects of electric fields on phase equilibria and interfacial transport have been investigated. So far, this project was directed at basic research on a broadly crosscutting concept. The results advocate continuation of this research in two directions, with the objective to solve problems related to solvent extraction of tank waste and groundwater treatment.
Date:
December 31, 2000
Creator:
Tsouris, Costas
Object Type:
Report
System:
The UNT Digital Library
Dynamical symmetry breaking in supersymmetric SU(n{sub c})and USp(2 n{sub c}) gauge theories
None
Date:
May 31, 2000
Creator:
Carlino, Giuseppe; Konishi, Kenichi & Murayama, Hitoshi
Object Type:
Article
System:
The UNT Digital Library
Improved Analytical Characterization of Solid Waste-Forms by Fundamental Development of Laser Ablation Technology
Laser ablation (LA) with inductively coupled plasma mass spectrometry (ICP-MS) has been demonstrated as a viable technology for sample characterization within the EM complex. Laser ablation systems have been set up at the Hanford Site, Savannah River Plant, the Pu immobilization program (MD), Los Alamos, and at numerous other DOE facilities. Characterization of elemental and isotopic chemical constituents is an important function in support of tank-waste operation and remediation functions. Proper waste characterization enables safe operation of the tank farms, resolution of tank safety questions, and development of processes and equipment for retrieval, pretreatment, and immobilization of tank waste. All of these operations are dependent on the chemical analysis of tank waste (1). A specified need by the Tanks Focus Area (TFA) is to validate the laser ablation mass spectrometer (LA/MS) technology through round robin testing of standard materials and through fundamental studies of the laser ablation process (2). Advancement of the laser ablation technology is warranted to guarantee accuracy of analysis for the diversity of complex EM samples. This EMSP research endeavored to understand fundamental laser-ablation and ICP-MS detection characteristics, to ensure accurate and sensitive analytical characterization for EM wastesite samples. The difficulty in characterization of EM waste samples …
Date:
December 31, 2000
Creator:
Russo, Richard E.
Object Type:
Report
System:
The UNT Digital Library
National Hispanic Bilingual Engineering Program (NHBEP)
This report describes program goals, activities, processes, benefits for the profession of engineering and for the project participants, coordination, and impact of NHBEP throughout the three years of implementation.
Date:
October 31, 2000
Creator:
Cruz, M.
Object Type:
Report
System:
The UNT Digital Library
High Resolution Prediction of Gas Injection Process Performance for Heterogeneous Reservoirs Quarterly Report
Gas injection in oil reservoirs offers huge potential for improved oil recovery. However, successful design of a gas injection process requires a detailed understanding of a variety of different significant processes, including the phase behavior of multicomponent mixtures and the approach to multi-contact miscibility in the reservoir, the flow of oil, water and gas underground, and the interaction of phase behavior reservoir heterogeneity and gravity on overall performance at the field scale. This project attempts to tackle all these issues using a combination of theoretical, numerical and laboratory studies of gas injection. The aim of this work is to develop a set of ultra-fast compositional simulation tools that can be used to make field-scale predictions of the performance of gas injection processes. To achieve the necessary accuracy, these tools must satisfy the fundamental physics and chemistry of the displacement from the pore to the reservoir scales. Thus this project focuses on four main research areas: (1) determination of the most appropriate methods of mapping multicomponent solutions to streamlines and streamtubes in 3D; (2) development of techniques for automatic generation of analytical solutions for one-dimensional flow along a streamline; (3) experimental investigations to improve the representation of physical mechanisms that govern …
Date:
December 31, 2000
Creator:
Hewett, Thomas A. & Orr, Franklin M., Jr.
Object Type:
Report
System:
The UNT Digital Library
Catalysts for High Cetane Ethers as Diesel Fuels Annual Report
A novel 1,2-ethanediol, bis(hydrogen sulfate), disodium salt precursor-based solid acid catalyst with a zirconia substrate was synthesized and demonstrated to have significantly enhanced activity and high selectivity in producing methyl isobutyl ether (MIBE) or isobutene from methanol-isobutanol mixtures. The precursor salt was synthesized and provided by Dr. T. H. Kalantar of the M.E. Pruitt Research Center, Dow Chemical Co., Midland, MI 48674. Molecular modeling of the catalyst synthesis steps and of the alcohol coupling reaction is being carried out. A representation of the methyl transfer from the surface activated methanol molecule (left) to the activated oxygen of the isobutanol molecule (right) to form an ether linkage to yield MIBE is shown.
Date:
August 31, 2000
Creator:
Klier, Kamil; Herman, Richard G.; Shen, James G.C. & Ma, Qisheng
Object Type:
Report
System:
The UNT Digital Library
Bioavailability Of Organic Solvents In Soils: Input Into Biologically Based Dose-Response Models for Human Risk Assessments
The purpose of this study is to determine the bioavailability of organic solvents following dermal exposures to contaminated soil and water. Breath analysis is being used to obtain real-time measurements of volatile organics in expired air following exposure in rats and humans. Rhesus monkeys were used as surrogates for humans in benzene exposures. The exhaled breath data was analyzed using physiologically based pharmacokinetic (PBPK) models to determine the dermal bioavailability of organic solvents under realistic exposure conditions. The end product of this research will be a tested framework for the rapid screening of real and potential exposures while simultaneously developing PBPK models to comprehensively evaluate and compare exposures to organic compounds from either contaminated soil or water.
Date:
December 31, 2000
Creator:
Wester, Ronald C.
Object Type:
Report
System:
The UNT Digital Library
Aqueous Electrochemical Mechanisms in Actinide Residue Processing
Plutonium and uranium residues (e.g., incinerator ash, combustibles, and sand/slag/crucibles) resulting from the purification and processing of nuclear materials constitute an enormous volume of ''lean'' processing waste and represent a significant fraction of the U. S. Department of Energy's (DOE) legacy waste from fifty years of nuclear weapons production activities. Much of this material is presently in storage at sites throughout the DOE weapons production complex (most notably Rocky Flats, Savannah River and Hanford) awaiting further processing and/or final disposition. The chemical and physical stability of much of this material has been called into question recently by the Defense Nuclear Facility Safety Board (DNFSB) and resulted in the issuance of a mandate by the DNFSB to undertake a program to stabilize these materials [1]. The ultimate disposition for much of these materials is anticipated to be geologic repositories such as the proposed Waste Isolation Pilot Plant in New Mexico. However, in light of the mandate to stabilize existing residues and the probable concomitant increase in the volume of material to be disposed as a result of stabilization (e.g., from repackaging at lower residue densities), the projected storage volume for these wastes within anticipated geologic repositories will likely be exceeded simply …
Date:
December 31, 2000
Creator:
Morris, David E.; Burns, Carol J.; Smith, Wayne H. & Blanchard
Object Type:
Report
System:
The UNT Digital Library
Design and Development of A New Hybrid Spectroelectrochemical Sensor
The general aim of this project is to design and implement a new sensor technology that offers the unprecedented levels of specificity needed for analysis of the complex chemical mixtures found at USDOE sites nationwide. The new sensor concept combines the elements of electrochemistry, spectroscopy and selective partitioning into a single device that provides three levels of selectivity. We have had three major goals: Demonstration of the general sensor concept on seven model systems; Development of a prototype sensor for ferrocyanide with associated instrumentation; and Testing prototype sensor for ferrocyanide on waste tank simulant (U-Plant-2 Simulant Solution) provided by PNNL and then on actual tank waste (Tank 241-C-112) at PNNL/Hanford
Date:
December 31, 2000
Creator:
Heineman, William R.; Seliskar, Carl J. & Ridgway, Thomas
Object Type:
Report
System:
The UNT Digital Library
USE OF SONICATION FOR IN-WELL SOFTENING OF SEMIVOLATILE ORGANIC COMPOUNDS
This project investigates the in-situ degradation of semivolatile organic compounds (SVOCs) and volatile organic compounds (VOCs) using in-well sonication, in-well vapor stripping, and bioremediation. Pretreating groundwaters with sonication techniques in-situ would form VOCs that can be effectively removed by in-well vapor stripping and bioremediation. The mechanistic studies focus on the coupling of megasonics and ultrasonics to ''soften'' (i.e., partially degrade) the SVOCs; oxidative reaction mechanism studies; surface corrosion studies (on the reactor walls/well); enhancement due to addition of oxidants, quantification of the hydroxyl radical formation; identification/quantification of degradation products; volatility/degradability of the treated waters; development of a computer simulation model to describe combined in-well sonication/in-well vapor stripping/bioremediation; systems analysis/economic analysis; large laboratory-scale experiment verification; and field demonstration of the integrated technology. Benefits of this approach include: (1) Remediation is performed in-situ; (2) The treatment systems complement each other; their combination can drastically reduce or remove SVOCs and VOCs; (3) Ability to convert hard-to-degrade organics into more volatile organic compounds; (4) Ability to remove residual VOCs and ''softened'' SVOCs through the combined action of in-well vapor stripping and biodegradation; (5) Does not require handling or disposing of water at the ground surface; and (6) Cost-effective and improved efficiency, resulting in shortened …
Date:
December 31, 2000
Creator:
Peters, Robert W.
Object Type:
Report
System:
The UNT Digital Library
LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES
This project has three main goals: Thin Films Studies, Preparation of Graded Porous Substrates and Basic Electrical Characterization and Testing of Planar Single Cells. During this time period substantial progress has been made in developing low temperature deposition techniques to produce dense, nanocrystalline yttrium-stabilized zirconia films on both dense oxide and polymer substrates. Progress has been made in the preparation and characterization of thin electrolytes and porous LSM substrates. Both of these tasks are essentially on or ahead of schedule. In our proposal, we suggested that the ZrO{sub 2}/Sc system needed to be considered as a candidate as a thin electrolyte. This was because microcrystalline ZrO{sub 2}/Sc has a significantly higher ionic conductivity than YSZ, particularly at the lower temperatures. As a result, some 0.5 micron thick film of ZrO{sub 2}/16% Sc on an alumina substrate (grain size 20nm) was prepared and the electrical conductivity measured as a function of temperature and oxygen activity. The Sc doped ZrO{sub 2} certainly has a higher conductivity that either 20nm or 2400nm YSZ, however, electronic conductivity dominates the conductivity for oxygen activities below 10{sup -15}. Whereas for YSZ, electronic conductivity is not a problem until the oxygen activity decreases below 10{sup -25}. These …
Date:
March 31, 2000
Creator:
Anderson, Harlan U.
Object Type:
Report
System:
The UNT Digital Library
Risk Reduction With a Fuzzy Expert Exploration Tool
Incomplete or sparse information on types of data such as geologic or formation characteristics introduces a high level of risk for oil exploration and development projects. ''Expert'' systems developed and used in several disciplines and industries, including medical diagnostics, have demonstrated beneficial results. A state-of-the-art exploration ''expert'' tool, relying on a computerized data base and computer maps generated by neural networks, is proposed for development through the use of ''fuzzy'' logic, a relatively new mathematical treatment of imprecise or non-explicit parameters and values. Oil prospecting risk can be reduced with the use of a properly developed and validated ''Fuzzy Expert Exploration (FEE) Tool.'' This tool will be beneficial in many regions of the US, enabling risk reduction in oil and gas prospecting and decreased prospecting and development costs. In the 1998-1999 oil industry environment, many smaller exploration companies lacked the resources of a pool of expert exploration personnel. Downsizing, low oil prices and scarcity of exploration funds have also affected larger companies, and will, with time, affect the end users of oil industry products in the US as reserves are depleted. The proposed expert exploration tool will benefit a diverse group in the US, leading to a more efficient use …
Date:
December 31, 2000
Creator:
Weiss, William W.
Object Type:
Report
System:
The UNT Digital Library
BIOFILTRATION OF VOLATILE POLLUTANTS: Fundamental Mechanisms for Improved Design, Long-term Operation, Prediction, and Implementation
Biofiltration systems can be used for treatment of volatile organic compounds (VOCs); however, the systems are poorly understood and are normally operated as ''black boxes''. Common operational problems associated with biofilters include fouling, deactivation, and overgrowth, all of which make them ineffective for continuous, long-term use. The objective of this investigation was to develop generic methods for long-term stable operation, in particular by using selective limitation of supplemental nutrients while maintaining high activity. As part of this effort, we have provided a deeper fundamental understanding of the important biological and transport mechanisms in biodestruction of sparingly soluble VOCs and have extended this approach and mathematical models to additional systems of high priority EM relevance--direct degradation and cometabolic degradation of priority pollutants such as BTEX and chlorinated organics. Innovative aspects of this project included development of a user-friendly two-dimensional predictive model/program for MS Windows 95/98/2000 to elucidate mass transfer and kinetic limitations in these systems, isolation of a unique microorganism capable of using sparingly soluble organic and chloroorganic VOCs as its sole carbon and energy source, and making long-term growth possible by successfully decoupling growth and degradation metabolisms in operating trickle bed bioreactors.
Date:
December 31, 2000
Creator:
Davison,Brian H.
Object Type:
Report
System:
The UNT Digital Library
Real-Time Broad Spectrum Characterization of Hazardous Mixed Waste by Membrane Introduction Mass Spectrometry
The goal of this project was to expand the range of chemical species that may be detected by membrane introduction mass spectrometry (MIMS) in environmental, and specifically in Mixed Waste, monitoring and characterization applications. Membrane introduction mass spectrometry (MIMS) functions as a near real-time monitor: there is little to no sample preparation and t analysis time is seconds to minutes. MIMS can be implemented as a flow injection technique, where samples, standards, and method blanks can be sequentially analyzed in a continuous fashion. The membrane acts as an interface between the sample (air or water) and the vacuum of the mass spectrometer. Transport of the analyte through the membrane occurs by the process of pervaporation. This process is described by adsorption to the outer surface of the membrane, diffusion through the membrane, and desorption from the inner membrane surface into a helium gas flow or into vacuum. The driving force for this work is the need for a rapid, sensitive, and broadly applicable tool for characterizing organic and metal-containing contaminants in a variety of DOE (and other) waste streams. In all characterization scenarios, a balance must be struck between evaluation of the hazards and their extent at a waste site, …
Date:
December 31, 2000
Creator:
Wilkerson Jr., Charles W.
Object Type:
Report
System:
The UNT Digital Library
Genetic Analysis of Stress Responses in Soil Bacteria for Enhanced Bioremediation of Mixed Contaminants
In order to realize the full potential of bioremediation, an understanding of microbial community and individual bacterial responses to the stresses encountered at contaminated sites is needed. Knowledge about genetic responses of soil and subsurface bacteria to environmental stresses, which include low nutrients, low oxygen, and mixed pollutants, will allow extrapolation of basic principles to field applications, either using indigenous bacteria or genetically engineered microorganisms. Defining bacterial responses to those stresses presents an opportunity for improving bioremediation strategies, both with indigenous populations and genetically-engineered microbes, and should contribute to environmental management and restoration actions that would reduce the cost and time required to achieve OEM's clean up goals. Stress-inducible genes identified in this project can be used as molecular probes for monitoring performance of indigenous bacteria as well as the effectiveness of bioremediation strategies being employed. Knowledge of survival and catabolic plasmid stability of indigenous bacteria will be needed for devising the most effective bioremediation strategy. In addition, stress-inducible regulatory elements identified in this project will be useful for creating genetically-engineered microorganisms which are able to degrade hazardous wastes under stress conditions at contaminated sites. One of the model organisms, Deinococcus radiodurans, is a stress-resistant bacterium. Thus, in addition to …
Date:
December 31, 2000
Creator:
Wong, Kwong-Kwok
Object Type:
Report
System:
The UNT Digital Library
Characterization of Chemically Modified Enzymes for Bioremediation Reactions
Remediation processes frequently involve species possessing limited solubility in water. For this project, we were interested in novel strategies using molecularly modified enzymes with enhanced activity and stability for remediation of recalcitrant compounds in organic solvents. Performance of naturally occurring enzymes is usually quite limited in such organic environments. The primary objective of the work was to gain a fundamental understanding of the molecular and catalytic properties of enzymes that have been chemically modified so that they are catalytically active and chemically stable in organic solvents. The premise was that stabilized and activated enzymes, which can function under harsh chemical conditions, are optimally suited for bioremediation in nonaqueous media where substrates of interest are more soluble and processed with greater efficiency. This unique strategy was examined with respect to the degradation of chlorophenols and PCBs.
Date:
December 31, 2000
Creator:
Davison, Brian H.
Object Type:
Report
System:
The UNT Digital Library
Photocatalytic and Chemical Oxidation of Organic Compounds in Supercritical Carbon Dioxide
The goal of the proposed research is to develop new chemistry for the removal of organic contaminants from supercritical carbon dioxide. This has application in processes used for continuous cleaning and extraction of parts and waste materials. Cleaning and extraction using supercritical carbon dioxide (scCO2) can be applied to the solution of a wide range of environmental and pollution prevention problems in the DOE complex. The objectives at the outset of the project were to: (1) determine if photocatalytic or other clean oxidation chemistry can be applied to the removal of organic or inorganic contaminants that are introduced into supercritical carbon dioxide during its use as an extraction and cleaning medium. The target will be contaminants left in solution after the bulk of solutes have been separated from the fluid phase by changing pressure and/or temperature (but not evaporating the CO2). This is applicable to development of efficient separations and will strengthen pollution prevention strategies that eliminate hazardous solvents and cleaning agents. (2) explore the use of supercritical carbon dioxide as a solvent for the photocatalytic oxidation of organic compounds and to compare it to other types of oxidation chemistry. This will add to the fundamental understanding of photocatalytic oxidation …
Date:
December 31, 2000
Creator:
Blake, Daniel M.
Object Type:
Report
System:
The UNT Digital Library
RADIATION EFFECTS IN NUCLEAR WASTE MATERIALS
The objective of this research was to develop fundamental understanding and predictive models of radiation effects in glasses and ceramics at the atomic, microscopic, and macroscopic levels, as well as an understanding of the effects of these radiation-induced solid-state changes on dissolution kinetics (i.e., radionuclide release). The research performed during the duration of this project has addressed many of the scientific issues identified in the reports of two DOE panels [1,2], particularly those related to radiation effects on the structure of glasses and ceramics. The research approach taken by this project integrated experimental studies and computer simulations to develop comprehensive fundamental understanding and capabilities for predictive modeling of radiation effects and dissolution kinetics in both glasses and ceramics designed for the stabilization and immobilization of high-level tank waste (HLW), plutonium residues and scraps, surplus weapons plutonium, other actinides, and other highly radioactive waste streams. Such fundamental understanding is necessary in the development of predictive models because all experimental irradiation studies on nuclear waste materials are ''accelerated tests'' that add a great deal of uncertainty to predicted behavior because the damage rates are orders of magnitude higher than the actual damage rates expected in nuclear waste materials. Degradation and dissolution processes …
Date:
December 31, 2000
Creator:
Weber, William J.
Object Type:
Report
System:
The UNT Digital Library