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A Widely Tunable Infrared Laser Spectrometer for Measurements of Isotopic Ratios of Carbon Cycle Gases (open access)

A Widely Tunable Infrared Laser Spectrometer for Measurements of Isotopic Ratios of Carbon Cycle Gases

The atmospheric abundances of carbon dioxide and methane have increased dramatically during the industrial era. Measurements of the isotopic composition of these gases can provide a powerful tool for quantifying their sources and sinks. This report describes the development of a portable instrument for isotopic analysis CO{sub 2} and CH{sub 4} using tunable infrared laser absorption spectroscopy. This instrument combines novel optical design and signal processing methods with a widely tunable mid-infrared laser source based on difference frequency generation (DFG) which will can access spectral regions for all the isotopes of CO{sub 2} and CH{sub 4} with a single instrument. The instrument design compensates for the large difference in concentration between major and minor isotopes by measuring them with path lengths which differ by a factor of 100 within the same multipass cell. During Phase I we demonstrated the basic optical design and signal processing by determining {sup 13}CO{sub 2} isotopic ratios with precisions as small as 0.2{per_thousand} using a conventional lead salt diode laser. During Phase II, the DFG laser source was coupled with the optical instrument and was demonstrated to detect {sup 13}CH{sub 4}/{sup 12}CH{sub 4} ratios with a precision of 0.5{per_thousand} and an averaging time of 20 …
Date: January 31, 2005
Creator: Shorter, Joanne H.; McManus, J. Barry; Nelson, David D.; Kolb, Charles E.; Zahniser, Mark S.; Bambha, Ray et al.
Object Type: Report
System: The UNT Digital Library
NANOSTRUCTURED CERAMICS AND COMPOSITES FOR REFRACTORY APPLICATIONS IN COAL GASIFICATION (open access)

NANOSTRUCTURED CERAMICS AND COMPOSITES FOR REFRACTORY APPLICATIONS IN COAL GASIFICATION

A class of ceramics, capable of exhibiting low coefficients of thermal expansion and catalytic properties was investigated. Investigations were directed towards nanoengineering of NZP ceramics and NZP-based composites by chemical means by controlling their compositions and processing variables. NaZr{sub 2}(PO{sub 4}){sub 3} (NZP) was synthesized by combining water-soluble precursors leading to the precipitation of a gel that was dried, calcined, pressed into pellets, then fired at 850 C. Without chemical additives, the resulting ceramic comprised pores ranging in size from approximately 25 to 50 nm and a surface area of about 30m{sup 2}/g. Hydroxyapatite, which has a needle-like morphology, was mechanically mixed with the calcined gel to template NZP crystallization. What resulted was a coarsening of the pore structure and a decrease in surface area. When copper nitrate was added to the solution during synthesis, the resulting ceramic underwent shrinkage upon firing as well as an increase in strength. HAp and copper additions combined resulted in 40% volume shrinkage and a doubling of the tensile strength to 16MPa. A very different type of porosity was achieved when silica was partly substituted for phosphorous in the NZP structure. Na{sub 3}Zr{sub 2}(Si{sub 2}P)O{sub 12} (NASCION) was synthesized in the same manner as …
Date: January 31, 2005
Creator: Brown, Paul
Object Type: Report
System: The UNT Digital Library
Applying Current Human Factors Engineering Guidance to Control Room Design (open access)

Applying Current Human Factors Engineering Guidance to Control Room Design

The Westinghouse Savannah River Company, a contractor to the Department of Energy, has compared Revisions 1 and 2 of NUREG-0700-Human System Interface Design Review Guideline, from the United States Nuclear Regulatory Commission Nuclear Regulatory Guide. The comparison has been made with respect to which guidelines remained the same, the guidelines that were reformatted or reworded, additional guidelines, and deleted guidelines. This comparison was made in preparation of revising the previously developed Human Factors Engineering Analysis Tool for automating the review, analysis, and evaluation of human system interface designs. This tool has been described at previous conferences on human factors and the merits and benefits of the tool described. The tool has been successfully applied to over eight facilities at WSRC. This paper describes the methodology and results of the comparison and the plans to enhance the already successful automation tool. The number of criteria in NUREG-0700 increased from approximately 1650 in Revision 1 to almost 2200 in Revision 2. Approximately 1600 criteria remained the same, though they were significantly reorganized; while about 100 were reworded or reformatted to clarify or expand the guidance provided. Around 600 guidelines were added and approximately 70 deleted. The majority of the changes and additions …
Date: January 31, 2005
Creator: Leo, Geary
Object Type: Article
System: The UNT Digital Library
Transport Locomotive and Waste Package Transporter ITS Standards Identification Study (open access)

Transport Locomotive and Waste Package Transporter ITS Standards Identification Study

To date, the project has established important to safety (ITS) performance requirements for structures, systems and components (SSCs) based on identification and categorization of event sequences that may result in a radiological release. These performance requirements are defined within the ''Nuclear Safety Design Basis for License Application'' (NSDB) (BSC 2005). Further, SSCs credited with performing safe functions are classified as ITS. In turn, performance confirmation for these SSCs is sought through the use of consensus code and standards. The purpose of this study is to identify applicable codes and standards for the waste package (WP) transporter and transport locomotive ITS SSCs. Further, this study will form the basis for selection and the extent of applicability of each code and standard. This study is based on the design development completed for License Application only. Accordingly, identification of ITS SSCs beyond those defined within the NSDB are based on designs that may be subject to further development during detail design. Furthermore, several design alternatives may still be under consideration to satisfy certain safety functions, and that final selection will not be determined until further design development has occurred. Therefore, for completeness, throughout this study alternative designs currently under consideration will be discussed. …
Date: March 31, 2005
Creator: Draper, K. D.
Object Type: Report
System: The UNT Digital Library
Parametric Evaluation of an Innovative Ultra-Violet PhotocatalyticOxidation (UVPCO) Air Cleaning Technology for Indoor Applications (open access)

Parametric Evaluation of an Innovative Ultra-Violet PhotocatalyticOxidation (UVPCO) Air Cleaning Technology for Indoor Applications

An innovative Ultra-Violet Photocatalytic Oxidation (UVPCO) air cleaning technology employing a semitransparent catalyst coated on a semitransparent polymer substrate was evaluated to determine its effectiveness for treating mixtures of volatile organic compounds (VOCs) representative of indoor environments at low, indoor-relevant concentration levels. The experimental UVPCO contained four 30 by 30-cm honeycomb monoliths irradiated with nine UVA lamps arranged in three banks. A parametric evaluation of the effects of monolith thickness, air flow rate through the device, UV power, and reactant concentrations in inlet air was conducted for the purpose of suggesting design improvements. The UVPCO was challenged with three mixtures of VOCs. A synthetic office mixture contained 27 VOCs commonly measured in office buildings. A building product mixture was created by combining sources including painted wallboard, composite wood products, carpet systems, and vinyl flooring. The third mixture contained formaldehyde and acetaldehyde. Steady state concentrations were produced in a classroom laboratory or a 20-m{sup 3} chamber. Air was drawn through the UVPCO, and single-pass conversion efficiencies were measured from replicate samples collected upstream and downstream of the reactor. Thirteen experiments were conducted in total. In this UVPCO employing a semitransparent monolith design, an increase in monolith thickness is expected to result …
Date: October 31, 2005
Creator: Hodgson, Alfred T.; Sullivan, Douglas P. & Fisk, William J.
Object Type: Report
System: The UNT Digital Library
High-Density Infrared Surface Treatments of Refractories (open access)

High-Density Infrared Surface Treatments of Refractories

Refractory materials play a crucial role in all energy-intensive industries and are truly a crosscutting technology for the Industries of the Future (IOF). One of the major mechanisms for the degradation of refractories and a general decrease in their performance has been the penetration and corrosion by molten metals or glass. Methods and materials that would reduce the penetration, wetting, and corrosive chemistry would significantly improve refractory performance and also maintain the quality of the processed liquid, be it metal or glass. This report presents the results of an R&D project aimed at investigating the use of high-density infrared (HDI) heating to surface treat refractories to improve their performance. The project was a joint effort between Oak Ridge National Laboratory (ORNL) and the University of Missouri-Rolla (UMR). HDI is capable of heating the near-surface region of materials to very high temperatures where sintering, diffusion, and melting can occur. The intended benefits of HDI processing of refractories were to (1) reduce surface porosity (by essentially sealing the surface to prevent liquid penetration), (2) allow surface chemistry changes to be performed by bonding an adherent coating onto the underlying refractory (in order to inhibit wetting and/or improve corrosion resistance), and (3) produce …
Date: March 31, 2005
Creator: Tiegs, T. N.
Object Type: Report
System: The UNT Digital Library
Manzanita Hybrid Power system Project Final Report (open access)

Manzanita Hybrid Power system Project Final Report

The Manzanita Indian Reservation is located in southeastern San Diego County, California. The Tribe has long recognized that the Reservation has an abundant wind resource that could be commercially utilized to its benefit, and in 1995 the Tribe established the Manzanita Renewable Energy Office. Through the U.S. Department of Energy's Tribal Energy Program the Band received funds to install a hybrid renewable power system to provide electricity to one of the tribal community buildings, the Manzanita Activities Center (MAC building). The project began September 30, 1999 and was completed March 31, 2005. The system was designed and the equipment supplied by Northern Power Systems, Inc, an engineering company with expertise in renewable hybrid system design and development. Personnel of the National Renewable Energy Laboratory provided technical assistance in system design, and continued to provide technical assistance in system monitoring. The grid-connected renewable hybrid wind/photovoltaic system provides a demonstration of a solar/wind energy hybrid power-generating project on Manzanita Tribal land. During the system design phase, the National Renewable Energy Lab estimated that the wind turbine is expected to produce 10,000-kilowatt hours per year and the solar array 2,000-kilowatt hours per year. The hybrid system was designed to provide approximately 80 percent …
Date: March 31, 2005
Creator: Frank, Trisha
Object Type: Report
System: The UNT Digital Library
Cost-Effective Method for Producing Self Supported Palladium Alloy Membranes for Use in Efficient Production of Coal Derived Hydrogen Quarterly Technical Progress Report: September 2003-July 2005, Revised (open access)

Cost-Effective Method for Producing Self Supported Palladium Alloy Membranes for Use in Efficient Production of Coal Derived Hydrogen Quarterly Technical Progress Report: September 2003-July 2005, Revised

Efforts in this quarter were concentrated on developing vacuum processing procedures to produce thinner (<4 {micro}m-thick), defect-free films over larger areas (>100 cm{sup 2}). We continued to test three different types of rigid supporting substrates, thermally oxidized silicon (10 cm diameter), polished borosilicate glass (10 cm diameter), and soda-lime glass (>100 cm{sup 2} areas), each representing a different cost, surface roughness, and chemistry. Mechanical integrity, defect density, and release characteristics of the films, though similar for the oxidized silicon and borosilicate glass, were distinctly different for the inexpensive soda-lime (float) glass; i.e., more sensitive to surface impurities. In general, films less than 4 {micro}m-thick were shown to be very sensitive to surface condition of the supporting substrate, particularly in the case of the soda-lime glass, to the point where surface strain overrode and dominated the intrinsic bulk stresses that are produced during the growth process. Therefore, in the near term (over the next quarter), large area films (>100 cm{sup 2}) will be produced at a minimum thickness of 5 {micro}m while further development will be conducted in subsequent quarters to reduce membrane thickness in large area films. Continued hydrogen permeation experiments and characterization of 5 and 10 {micro}m-thick, Pd-Cu films, …
Date: August 31, 2005
Creator: Lanning, B. & Arps, J.
Object Type: Report
System: The UNT Digital Library
Ocean carbon sequestration by fertilization: An integrated bioeochemical assessment (open access)

Ocean carbon sequestration by fertilization: An integrated bioeochemical assessment

Under this grant, the authors investigated a range of issues associated with the proposal to fertilize the ocean with nutrients (such as iron) in order to increase the export of organic matter from the ocean's near surface waters and consequently increase the uptake of CO{sub 2} from the atmosphere. There are several critical scientific questions that have the potential to be make-or-break issues for this proposed carbon sequestration mechanism: (1) If iron is added to the ocean, will export of organic carbon from the surface actually occur? Clearly, if no export occurs, then there will be no sequestration. (2) if iron fertilization does lead to export of organic carbon from the surface of the ocean, how much CO{sub 2} will actually be removed from the atmosphere? Even if carbon is removed from the surface of the ocean, this does not guarantee that there will be significant removal of CO{sub 2} from the atmosphere, since the CO{sub 2} may be supplied by a realignment of dissolved inorganic carbon within the ocean. (3) What is the time scale of any sequestration that occurs? If sequestered CO{sub 2} returns to the atmosphere on a relatively short time scale, iron fertilization will not contribute …
Date: May 31, 2005
Creator: Gruber, N.; Sarmiento, J.L. & Gnandesikan, A.
Object Type: Report
System: The UNT Digital Library
Developing State Policies Supportive of Bioenergy Development (open access)

Developing State Policies Supportive of Bioenergy Development

None
Date: July 31, 2005
Creator: Baskin, Kathryn
Object Type: Report
System: The UNT Digital Library
Surface Structures of Cubo-octahedral Pt-Mo Catalyst Nanoparticles from Monte Carlo Simulations (open access)

Surface Structures of Cubo-octahedral Pt-Mo Catalyst Nanoparticles from Monte Carlo Simulations

The surface structures of cubo-octahedral Pt-Mo nanoparticles have been investigated using the Monte Carlo method and modified embedded atom method potentials that we developed for Pt-Mo alloys. The cubo-octahedral Pt-Mo nanoparticles are constructed with disordered fcc configurations, with sizes from 2.5 to 5.0 nm, and with Pt concentrations from 60 to 90 at. percent. The equilibrium Pt-Mo nanoparticle configurations were generated through Monte Carlo simulations allowing both atomic displacements and element exchanges at 600 K. We predict that the Pt atoms weakly segregate to the surfaces of such nanoparticles. The Pt concentrations in the surface are calculated to be 5 to 14 at. percent higher than the Pt concentrations of the nanoparticles. Moreover, the Pt atoms preferentially segregate to the facet sites of the surface, while the Pt and Mo atoms tend to alternate along the edges and vertices of these nanoparticles. We found that decreasing the size or increasing the Pt concentration leads to higher Pt concentrations but fewer Pt-Mo pairs in the Pt-Mo nanoparticle surfaces.
Date: March 31, 2005
Creator: Wang, Guofeng; Van Hove, M.A.; Ross, P.N. & Baskes, M.I.
Object Type: Article
System: The UNT Digital Library
Calibration and Testing of Sonic Stimulation Technologies (open access)

Calibration and Testing of Sonic Stimulation Technologies

In conjunction with Baker Atlas Inc. Michigan Technological University devised a system capable of recording the earth motion and pressure due to downhole and surface seismic sources. The essential elements of the system are 1) a borehole test site that will remain constant and is available all the time and for any length of time, 2) a downhole sonde that will itself remain constant and, because of its downhole digitization feature, does not require the wireline or surface recording components to remain constant, and 3) a set of procedures that ensures that the amplitude and frequency parameters of a wide range of sources can be compared with confidence. This system was used to record four seismic sources, three downhole sources and one surface source. A single activation of each of the downhole sources was not seen on time traces above the ambient noise, however, one sweep of the surface source, a small vertical vibrator, was easily seen in a time trace. One of the downhole sources was seen by means of a spike in its spectrum and a second downhole source was clearly seen after correlation and stacking. The surface vibrator produced a peak to peak particle motion signal of …
Date: March 31, 2005
Creator: Turpening, Roger M. & D.Pennington, Wayne
Object Type: Report
System: The UNT Digital Library
Feasibility Study of Compact Gas-Filled Storage Ring for 6D Cooling of Muon Beams (open access)

Feasibility Study of Compact Gas-Filled Storage Ring for 6D Cooling of Muon Beams

The future of elementary particle physics in the USA depends in part on the development of new machines such as the International Linear Collider, Muon Collider and Neutrino Factories which can produce particle beams of higher energy, intensity, or particle type than now exists. These beams will enable the continued exploration of the world of elementary particles and interactions. In addition, the associated development of new technologies and machines such as a Muon Ring Cooler is essential. This project was to undertake a feasibility study of a compact gas-filled storage ring for 6D cooling of muon beams. The ultimate goal, in Phase III, was to build, test, and operate a demonstration storage ring. The preferred lattice for the storage ring was determined and dynamic simulations of particles through the lattice were performed. A conceptual design and drawing of the magnets were made and a study of the RF cavity and possible injection/ejection scheme made. Commercial applications for the device were investigated and the writing of the Phase II proposal completed. The research findings conclude that a compact gas-filled storage ring for 6D cooling of muon beams is possible with further research and development.
Date: October 31, 2005
Creator: Garren, A. & Kolonlo, J.
Object Type: Report
System: The UNT Digital Library
Electrons and gas versus high brightness ion beams (open access)

Electrons and gas versus high brightness ion beams

None
Date: March 31, 2005
Creator: Molvik, A. W.; Cohen, R. H.; Bieniosek, F.; Friedman, A.; Kireeff Covo, M.; Lund, S. M. et al.
Object Type: Article
System: The UNT Digital Library
Advanced Strained-Superlattice Photocathodes for Polarized Electron Sources (open access)

Advanced Strained-Superlattice Photocathodes for Polarized Electron Sources

Polarized electrons have been essential for high-energy parity-violating experiments and measurements of the nucleon spin structure. The availability of a polarized electron beam was crucial to the success of the Stanford Linear Collider (SLC) in achieving a precise measurement of the electroweak mixing angle, and polarized electron beams will be required for all future linear colliders. Polarized electrons are readily produced by GaAs photocathode sources. When a circularly polarized laser beam tuned to the bandgap minimum is directed to the negative-electron-affinity (NEA) surface of a GaAs crystal, longitudinally polarized electrons are emitted into vacuum. The electron polarization is easily reversed by reversing the laser polarization. The important properties of these photocathodes for accelerator applications are: degree of polarization of the extracted beam; ability to extract sufficient charge to meet accelerator pulse-structure requirements; efficiency and stability of operation; and absence of any asymmetries in the beam properties (charge, position, energy, etc.) upon polarization reversal. The performance of GaAs photocathodes has improved significantly since they were first introduced in 1978 [1]. The theoretical maximum polarization of 50% for natural GaAs was first exceeded in 1991 using the lattice mismatch of a thin InGaAs layer epitaxially grown over a GaAs substrate to generate …
Date: January 31, 2005
Creator: Moy, Dr. Aaron
Object Type: Report
System: The UNT Digital Library
An Advanced Fracture Characterization and Well Path Navigation System for Effective Re-Development and Enhancement of Ultimate Recovery From the Complex Monterey Reservoir of South Ellwood Field, Offshore California, Quarterly Report: October - December 2004 (open access)

An Advanced Fracture Characterization and Well Path Navigation System for Effective Re-Development and Enhancement of Ultimate Recovery From the Complex Monterey Reservoir of South Ellwood Field, Offshore California, Quarterly Report: October - December 2004

Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase …
Date: January 31, 2005
Creator: Horner, Steve
Object Type: Report
System: The UNT Digital Library
The NOx System in Homogeneous and Heterogeneous Nuclear Waste (open access)

The NOx System in Homogeneous and Heterogeneous Nuclear Waste

None
Date: August 31, 2005
Creator: Meisel, Dan; Bentley, John; Carmichael, Ian; Chipman, Daniel; Hug, Gordon; Camaioni, Donald et al.
Object Type: Report
System: The UNT Digital Library
Distributed Physical and Molecular Separations for Selective Harvest of Higher Value Wheat Straw Components Project (open access)

Distributed Physical and Molecular Separations for Selective Harvest of Higher Value Wheat Straw Components Project

Wheat straw (Triticum aestivum L.) is an abundant source of plant fiber. It is regenerated, in large quantities, every year. At present, this potentially valuable resource is greatly under-exploited. Most of the excess straw biomass (i.e., tonnage above that required for agronomic cropping system sustainability) is managed through expensive chopping/tillage operations and/or burnt in the field following harvest, resulting in air pollution and associated health problems. Potential applications for wheat straw investigated within this project include energy and composites manufacture. Other methods of straw utilization that will potentially benefit from the findings of this research project include housing and building, pulp and paper, thermal insulation, fuels, and chemicals. This project focused on components of the feedstock assembly system for supplying a higher value small grains straw residue for (1) gasification/combustion and (2) straw-thermoplastic composites. This project was an integrated effort to solve the technological, infrastructural, and economic challenges associated with using straw residue for these bioenergy and bioproducts applications. The objective of the research is to contribute to the development of a low-capital distributed harvesting and engineered storage system for upgrading wheat straw to more desirable feedstocks for combustion and for straw-plastic composites. We investigated two processes for upgrading wheat …
Date: January 31, 2005
Creator: Hess, J.R
Object Type: Report
System: The UNT Digital Library
CO2 Capture by Absorption With Potassium Carbonate Quarterly Report (open access)

CO2 Capture by Absorption With Potassium Carbonate Quarterly Report

The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. The baseline campaign with 30% MEA has given heat duties from 40 to 70 kcal/gmol CO{sub 2} as predicted by the stripper model. The Flexipak 1Y structured packing gives significantly better performance than IMTP 40 duped packing in the absorber, but in the stripper the performance of the two packings is indistinguishable. The FTIR analyzer measured MEA volatility in the absorber represented by an activity coefficient of 0.7. In the MEA campaign the material balance closed with an average error of 3.5% and the energy balance had an average error of 5.9.
Date: July 31, 2005
Creator: Rochelle, Gary T.; Hilliard, Marcus; Chen, Eric; Oyenekan, Babatunde; Dugas, Ross & McLees, John
Object Type: Report
System: The UNT Digital Library
TOXICOLOGICAL EVALUATION OF REALISTIC EMISSIONS OF SOURCE AEROSOLS (TERESA): APPLICATION TO POWER PLANT-DERIVED PM2.5 (open access)

TOXICOLOGICAL EVALUATION OF REALISTIC EMISSIONS OF SOURCE AEROSOLS (TERESA): APPLICATION TO POWER PLANT-DERIVED PM2.5

This report documents progress made on the subject project during the period of September 1, 2004 through February 28, 2005. The TERESA Study is designed to investigate the role played by specific emissions sources and components in the induction of adverse health effects by examining the relative toxicity of coal combustion and mobile source (gasoline and/or diesel engine) emissions and their oxidative products. The study involves on-site sampling, dilution, and aging of coal combustion emissions at three coal-fired power plants, as well as mobile source emissions, followed by animal exposures incorporating a number of toxicological endpoints. The DOE-EPRI Cooperative Agreement (henceforth referred to as ''the Agreement'') for which this technical progress report has been prepared covers the performance and analysis of field experiments at the first TERESA plant, located in the Upper Midwest and henceforth referred to as Plant 0, and at two additional coal-fired power plants (Plants 1 and 2) utilizing different coal types and with different plant configurations. During this reporting period, all fieldwork at Plant 0 was completed. Stack sampling was conducted in October to determine if there were significant differences between the in-stack PM concentrations and the diluted concentrations used for the animal exposures. Results indicated …
Date: March 31, 2005
Creator: Rohr, Annette
Object Type: Report
System: The UNT Digital Library
Establishment of an Industry-Driven Consortium Focused on Improving the Production Performance of Domestic Stripper Wells (open access)

Establishment of an Industry-Driven Consortium Focused on Improving the Production Performance of Domestic Stripper Wells

None
Date: August 31, 2005
Creator: Morrison, Joel L.
Object Type: Report
System: The UNT Digital Library
DESIGN, SYNTHESIS, AND MECHANISTIC EVALUATION OF IRON-BASED CATALYSIS FOR SYNTHESIS GAS CONVERSION TO FUELS AND CHEMICALS (open access)

DESIGN, SYNTHESIS, AND MECHANISTIC EVALUATION OF IRON-BASED CATALYSIS FOR SYNTHESIS GAS CONVERSION TO FUELS AND CHEMICALS

This project explores the extension of previously discovered Fe-based catalysts to hydrogen-poor synthesis gas streams derived from coal and biomass sources. These catalysts have previously shown unprecedented Fischer-Tropsch synthesis rate, selectivity with synthesis gas derived from methane. During the first reporting period, we certified a microreactor, installed required analytical equipment, and reproduced synthetic protocols and catalytic performance previously reported. During the second reporting period, we prepared several Fe-based compositions for Fischer-Tropsch synthesis and tested the effects of product recycle under both subcritical and supercritical conditions. During this third reporting period, we have prepared a large number of Fe-based catalyst compositions using precipitation and impregnations methods with both supercritical and subcritical drying and with the systematic use of surface active agents to prevent pore collapse during drying steps required in synthetic protocols. These samples were characterized during this period using X-ray diffraction, surface area, and temperature-programmed reduction measurements. These studies have shown that these synthesis methods lead to even higher surface areas than in our previous studies and confirm the crystalline structures of these materials and their reactivity in both oxide-carbide interconversions and in Fischer-Tropsch synthesis catalysis. Fischer-Tropsch synthesis reaction rates and selectivities with low H{sub 2}/CO ratio feeds (H{sub 2}/CO …
Date: March 31, 2005
Creator: Ishikawa, Akio; Ojeda, Manuel & Iglesia, Enrique
Object Type: Report
System: The UNT Digital Library
Industrial Membrane Filtration and Short-bed Fractal Separation Systems for Separating Monomers from Heterogeneous Plant Material (open access)

Industrial Membrane Filtration and Short-bed Fractal Separation Systems for Separating Monomers from Heterogeneous Plant Material

Large-scale displacement of petroleum will come from low-cost cellulosic feedstocks such as straw and corn stover crop residues. This project has taken a step toward making this projection a reality by reducing capital and energy costs, the two largest cost factors associated with converting cellulosic biomass to chemicals and fuels. The technology exists for using acid or enzyme hydrolysis processes to convert biomass feedstock (i.e., waste cellulose such as straw, corn stover, and wood) into their base monomeric sugar building blocks, which can, in turn, be processed into chemicals and fuels using a number of innovative fermentation technologies. However, while these processes are technically possible, practical and economic barriers make these processes only marginally feasible or not feasible at all. These barriers are due in part to the complexity and large fixed and recurring capital costs of unit operations including filtration, chromatographic separation, and ion exchange. This project was designed to help remove these barriers by developing and implementing new purification and separation technologies that will reduce the capital costs of the purification and chromatographic separation units by 50% to 70%. The technologies fundamental to these improvements are: (a) highly efficient clarification and purification systems that use screening and membrane …
Date: March 31, 2005
Creator: Kearney, M; Kochergin, V; Hess, R; Foust, T; Herbst, R & Mann, N
Object Type: Report
System: The UNT Digital Library
Comprehensive Renewable Energy Feasibility Study for the Makah Indian Tribe (open access)

Comprehensive Renewable Energy Feasibility Study for the Makah Indian Tribe

The purpose of this project was to determine the technical feasibility, economic viability, and potential impacts of installing and operating a wind power station and/or small hydroelectric generation plants on the Makah reservation. The long-term objective is to supply all or a portion of Tribe's electricity from local, renewable energy sources in order to reduce costs, provide local employment, and reduce power outages. An additional objective was for the Tribe to gain an understanding of the requirements, costs, and benefits of developing and operating such plants on the reservation. The Makah Indian Reservation, with a total land area of forty-seven square miles, is located on the northwestern tip of the Olympic Peninsula in Washington State. Four major watersheds drain the main Reservation areas and the average rainfall is over one hundred inches per year. The reservation's west side borders the Pacific Ocean, but mostly consists of rugged mountainous terrain between 500 and 1,900 feet in elevation. Approximately 1,200 tribal members live on the Reservation and there is an additional non-Indian residential population of about 300. Electric power is provided by the Clallam County PUD. The annual usage on the reservation is approximately 16,700 mWh. Project Work Wind Energy--Two anemometer suites …
Date: March 31, 2005
Creator: RobertLynette; Wade, John & Coupe, Larry
Object Type: Report
System: The UNT Digital Library