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The challenge of implementing an IRP process in Asia: The case of Hainan Province, China (open access)

The challenge of implementing an IRP process in Asia: The case of Hainan Province, China

Developing a modern electric power sector is necessary for economic growth and development to proceed. Institutions to implement an IRP (integrated resource planning) process do not exist in many countries. Hainan`s economy is growing rapidly with a concomitant increase in electricity demand. This is an ideal time in Hainan`s development to implement an IRP process. The challenge is for Hainan to develop institutions and incentive mechanisms for HEPCO (Hainan Electric Power Co.) to adopt cost-based pricing, run DSM programs, construct renewable generating plants, etc. One proposal is to great a Hainan government-wide IRP committee.
Date: December 31, 1994
Creator: Hill, L.J.
Object Type: Article
System: The UNT Digital Library
Changing mass liner system for generation of soft X-radiation (open access)

Changing mass liner system for generation of soft X-radiation

This report is issued in compliance with Clause F.4.2 of Contract 4769M0014-9Y ``Design study for X-ray generation``. In the first report (Clause F.4.1 of Contract) three systems were considered to solve the formulated problem. All of them were designed on the basis of employment of {O}400 mm disk explosive-magnetic generators (DEMG) as an energy source using a high-speed (25--30 cm/{micro}s) liner converging to the axis. The considered systems differs in modes of current pulse formation. For further effort the customer has chosen System 3 with the changing mass liner. In accordance with this fact this report discusses basic theoretical and computational results obtained to date for System 3. Further development of the theory of the considered system is suggested in the context of the series of experiments the ultimate goal of which is to generate soft X-radiation. Basic stages of the effort to generate soft X-radiation are discussed on the basis of the schedule given with consideration of some corrections which occurred when the system type had been selected.
Date: December 31, 1994
Creator: Mokhov, V. N.; Buyko, A. M.; Burenkov, O. M.; Garanin, S. F.; Startsev, A. I. & Yakubov, V. B.
Object Type: Report
System: The UNT Digital Library
Characterizadtion of porosity via secondary reactions. Quarterly technical progress report, 1 July 1994--30 September 1994 (open access)

Characterizadtion of porosity via secondary reactions. Quarterly technical progress report, 1 July 1994--30 September 1994

The following was accomplished during the reporting period: Comparisons between porosity characterization data obtained from nitrogen adsorption isotherms, and that revealed by CO and CO{sub 2} temperature programmed desorption (TPD) spectra were performed for Pittsburgh {number_sign}8 coal char samples prepared at various degrees of burn-off, ranging from 0--72% burn-off, in 0.1 MPa oxygen at 470{degrees}C. Conclusions derived from these analyses include: The CO TPD spectra correlate the development of the microporosity; and the CO{sub 2} spectra correlate the development of the larger, external porosity. This behavior is the same as we have observed for Wyodak coal char. This behavior is currently attributed to the restriction of formation of the larger C0{sub 2}-liberating oxygen surface complexes (e.g., lactones, carboxylic acid anhydrides) to the larger, external porosity, while the smaller CO{sub 2}-liberating complexes (e.g., carbonyls, semi-quinones) form on the surfaces of all they porosity, but since the microporosity accounts for the bulk of the surface area, the latter correlates the microporosity quite well. Together with the Wyodak coal char results, these data represent the first time that this particular connection has been made between porosity development and TPD spectra.
Date: December 31, 1994
Creator: Calo, J.M. & Zhang, L.
Object Type: Report
System: The UNT Digital Library
Characterization and performance of carbon films deposited by plasma and ion beam based techniques (open access)

Characterization and performance of carbon films deposited by plasma and ion beam based techniques

Plasma and ion beam based techniques have been used to deposit carbon-based films. The ion beam based method, a cathodic arc process, used a magnetically mass analyzed beam and is inherently a line-of-sight process. Two hydrocarbon plasma-based, non-line-of-sight techniques were also used and have the advantage of being capable of coating complicated geometries. The self-bias technique can produce hard carbon films, but is dependent on rf power and the surface area of the target. The pulsed-bias technique can also produce hard carbon films but has the additional advantage of being independent of rf power and target surface area. Tribological results indicated the coefficient of friction is nearly the same for carbon films from each deposition process, but the wear rate of the cathodic arc film was five times less than for the self-bias or pulsed-bias films. Although the cathodic arc film was the hardest, contained the highest fraction of sp{sup 3} bonds and exhibited the lowest wear rate, the cathodic arc film also produced the highest wear on the 440C stainless steel counterface during tribological testing. Thus, for tribological applications requiring low wear rates for both counterfaces, coating one surface with a very hard, wear resistant film may detrimentally affect …
Date: December 31, 1994
Creator: Walter, K. C.; Kung, H. & Levine, T.
Object Type: Article
System: The UNT Digital Library
Characterization and reclamation assessment for the central shops diesel storage facility at Savannah River Site (open access)

Characterization and reclamation assessment for the central shops diesel storage facility at Savannah River Site

The contamination of subsurface terrestrial environments by organic contaminants is a global phenomenon. The remediation of such environments requires innovative assessment techniques and strategies for successful cleanups. Using innovative approaches, the central Shops Diesel Storage Facility at the Savannah River Site (SRS) was characterized to determine the extent of subsurface diesel fuel contamination. Effective bioremediation techniques for cleaning up of the contaminant plume were established.
Date: December 31, 1994
Creator: Fliermans, C.B.; Hazen, T.C. & Bledsoe, H.W.
Object Type: Report
System: The UNT Digital Library
Characterization of a desert soil sequence at Yucca Mountain, NV (open access)

Characterization of a desert soil sequence at Yucca Mountain, NV

Yucca Mountain, Nevada, is currently being evaluated as a potential site for a geologic repository for high level radioactive waste. Hydrologic evaluation of the unsaturated zone of Yucca Mountain is being conducted as an integrated set of surface and subsurface-based activities with a common objective to characterize the temporal and spatial distribution of water flux through the potential repository. Yucca Mountain is covered with a thin to thick layer of colluvial/alluvial materials, where there are not bedrock outcrops. It is across this surface boundary that all infiltration and all exfiltration occurs. This surface boundary effects water movement through the unsaturated zone. Characterization of the hydrologic properties of surficial materials is then a necessary step for short term characterization goals and for long term modeling.
Date: December 31, 1994
Creator: Guertal, William R.; Flint, Alan L.; Hofmann, Lon L. & Hudson, David B.
Object Type: Article
System: The UNT Digital Library
Characterization of defects in deuterium-implanted beryllium (open access)

Characterization of defects in deuterium-implanted beryllium

This work investigated surface material modifications in high-purity beryllium foils resulting from 1-keV deuterium ion implantation into specimens for which the anneal temperatures and implantation temperatures were varied. Defects in unimplanted and in deuterium-implanted beryllium were characterized principally by positron-beam depth-profile analyses. Depth-profiles of the defect distributions in the specimens were made by stepping the energy of the positron beam from 0.055 keV to 40 keV, accompanied by measurements of the Doppler-broadened annihilation radiation line shape at each positron energy. These analyses identified a varying defect structure in beryllium, dependent on the previous anneal history of the material and on the temperature of the material during implantation with energetic deuterium ions. For specimens implanted at room temperature with 1-keV/D ions, the beam-induced defect structure had a profile that was peaked near the mean. range of the implanting deuterium and that extended beyond the implantation zone. Isochronal step-thermal anneal experiments revealed that deuterium was released from these defects at a temperature of about 400K, indicative of shallow traps, and that the defect structure annealed at temperatures above 623K. The beam-induced vacancy-defect complexes were estimated to be 1-nm voids for 1-keV/D implantation into Be at room temperature. For beryllium implanted at temperatures …
Date: December 31, 1994
Creator: Anderl, R. A.; Denison, A. B.; Szpala, S.; Asoka-Kumar, P.; Lynn, K. G. & Nielsen, B.
Object Type: Article
System: The UNT Digital Library
Characterization of high-level waste saltcake stored at the Savannah River Site (open access)

Characterization of high-level waste saltcake stored at the Savannah River Site

Approximately 34 million gallons of high-level nuclear waste (HLW) are stored at the Savannah River Site (SRS) in 51 underground storage tanks. Facilities have been constructed to permanently dispose of this waste. The radioactive components will be separated from the bulk of the waste into a small volume fraction and vitrified in the Defense Waste Processing Facility (DWPF). The remaining, much larger volume fraction will be incorporated into a cement waste form in the Saltstone facility. Most of the radioactivity in the HLW is present in a solids fraction referred to as sludge. These solids are produced upon addition of sodium hydroxide to the acidic waste solutions to provide a highly alkaline slurry. The highly alkaline condition is necessary to prevent corrosion of the carbon steel storage tanks. After allowing the sludge solids to settle, the waste solutions are decanted and evaporated to conserve storage space in the tanks. Upon cooling, salts are crystallized from the evaporated wastes. The crystallized salts are referred to as saltcake.
Date: December 31, 1994
Creator: Hobbs, D. T. & Coleman, C. J.
Object Type: Article
System: The UNT Digital Library
Characterization of indoor and outdoor pool fires with active calorimetry (open access)

Characterization of indoor and outdoor pool fires with active calorimetry

A water cooled, 1 m {times} 1 m, vertical calorimeter panel has been used in conjunction with other fire diagnostics to characterize a 6 m {times} 6 m outdoor and three 3 m {times} 3 m indoor JP-4 pool fires. Measurements reported include calorimeter surface heat flux and surface temperatures, flame temperatures, and gas flow velocities in the fire. From the data, effective radiative absorption coefficients for various zones in the fires have been estimated. The outdoor test was conducted at Sandia`s Coyote Canyon test facility, while indoor tests were conducted at the indoor SMokE Reduction Facility (SMERF) at the same location. The measurements provide data useful in calibrating simple analytic fire models intended for the analysis of packages containing hazardous materials.
Date: December 31, 1994
Creator: Koski, J. A.; Gill, W.; Gritzo, L. A.; Kent, L. A. & Wix, S. D.
Object Type: Article
System: The UNT Digital Library
Characterization of mercury forms in contaminated floodplain soils (open access)

Characterization of mercury forms in contaminated floodplain soils

The chemical form or speciation of Hg in the floodplain soils of the East Fork Poplar Creek in Oak Ridge TN, a site contaminated from past industrial activity, was investigated. Hg speciation in the soils is an important factor in controlling the fate and effect of mercury at the site and in assessing human health and ecological risk. Application of 3 different sequential extraction speciation schemes indicated the Hg at the site was predominantly relatively insoluble mercuric sulfide or metallic Hg, though the relative proportions of each did not agree well between procedures. Application of x-ray and electron beam studies to site soils confirmed the presence of metacinnabar, a form of mercuric sulfide, the first known evidence of authigenic mercuric sulfide formation in soils.
Date: December 31, 1994
Creator: Barnett, M. O.; Turner, R. R.; Henson, T. J.; Harris, L. A.; Melton, R. E. & Stevenson, R.J.
Object Type: Article
System: The UNT Digital Library
Characterization of radioactive contamination inside pipes with the Pipe Explorer{trademark} system (open access)

Characterization of radioactive contamination inside pipes with the Pipe Explorer{trademark} system

The objective for the development of the Pipe Explorer{trademark} radiological characterization system is to achieve a cost effective, low risk means of characterizing gamma radioactivity on the inside surface of pipes. The unique feature of this inspection system is the use of a pneumatically inflated impermeable membrane which transports the detector into the pipe as it inverts. The membrane`s internal air pressure tows the detector and tether through the pipe. This mechanism isolates the detector and its cabling from the contaminated surface, yet allows measurement of radioactive emissions which can readily penetrate the thin plastic membrane material (such as gamma and high energy beta emissions). In Phase 1, an initial survey of DOE facilities was conducted to determine the physical and radiological characteristics of piping systems. The inverting membrane deployment system was designed and extensively tested in the laboratory. A range of membrane materials was tested to evaluate their ruggedness and deployment characteristics. Two different sizes of gamma scintillation detectors were procured and tested with calibrated sources. Radiation transport modeling evaluated the measurement system`s sensitivity to detector position relative to the contaminated surface, the distribution of the contamination, background gamma levels, and gamma source energy levels. In the culmination of …
Date: December 31, 1994
Creator: Lowry, W.
Object Type: Article
System: The UNT Digital Library
Characterization of residual stresses in graded ceramic-metal structures: A comparison of diffraction experiments and FEM calculations (open access)

Characterization of residual stresses in graded ceramic-metal structures: A comparison of diffraction experiments and FEM calculations

Numerical models have been extensively developed for predicting the thermomechanical behavior of ceramic-metal joints containing graded interlayers. The goal of such modeling is to be able to design optimum interlayer microstructural characteristics required to meet the needs of specific application conditions, and to use this design information to guide component fabrication. The graded specimen examined in this research was fabricated by powder processing methods. Al{sub 2}O{sub 3}-Ni was selected as a model system. The residual stresses expected in the specimen were predicted by FEM calculations using an elastic-plastic model. Strain and stress distributions in the specimen were characterized experimentally using x-ray and neutron diffraction techniques. Preliminary neutron and x-ray diffraction measurements were not in very good agreement with FEM model predictions, particularly regarding the in-plane stresses along the axis of symmetry. These results suggest additional diffraction measurements on graded specimens having fewer interlayers should be carried out, and experimental verification of the constitutive assumptions used in the FEM model is needed.
Date: December 31, 1994
Creator: Rabin, B.H.; Williamson, R.L.; Watkins, T.R.; Wang, X.L.; Hubbard, C.R. & Spooner, S.
Object Type: Report
System: The UNT Digital Library
Characterization of trapped gas saturation and heterogeneity in core samples using miscible-displacement experiments (open access)

Characterization of trapped gas saturation and heterogeneity in core samples using miscible-displacement experiments

Trapped gas saturation and permeability heterogeneity were evaluated in Berea cores at reservoir conditions, using standard miscible displacement experiments, with and without surfactants. Pressure and production history were influenced by core heterogeneity and foam lamellae formation when aqueous surfactant was present in the core. A simple dispersion model and a three-coefficient dispersion-capacitance model (Coates-Smith) were fit to the experimental data. The dispersion-capacitance model successfully matched the experiments in which foam lamella formed, while the simple dispersion model was used only for determining initial core flow heterogeneity. The objective of the dispersion-capacitance model was to estimate trapped gas saturations; however longitudinal dispersion and mass transfer also were examined. The results show that the dispersion-capacitance model accurately fits trapped gas saturation controlled by rock heterogeneities and foam lamellae for lamella generating mechanisms that allow a continuous gas phase (leave-behind lamellae). The practical applications resulting from this study can aid in core sample selection and scaling short laboratory corefloods to field dimensions for applications to foam stimulation and underground storage of natural gas.
Date: December 31, 1994
Creator: Smith, D.H. & Jikich, S.A.
Object Type: Report
System: The UNT Digital Library
Characterization of vegetation properties: Canopy modeling of pinyon-juniper and ponderosa pine woodlands; Final report. Modeling topographic influences on solar radiation: A manual for the SOLARFLUX model (open access)

Characterization of vegetation properties: Canopy modeling of pinyon-juniper and ponderosa pine woodlands; Final report. Modeling topographic influences on solar radiation: A manual for the SOLARFLUX model

This report is comprised of two studies. The first study focuses on plant canopies in pinyon-juniper woodland, ponderosa pine woodland, and waste sites at Los Alamos National Laboratory which involved five basic areas of research: (1) application of hemispherical photography and other gap fraction techniques to study solar radiation regimes and canopy architecture, coupled with application of time-domain reflectometry to study soil moisture; (2) detailed characterization of canopy architecture using stand mapping and allometry; (3) development of an integrated geographical information system (GIS) database for relating canopy architecture with ecological, hydrological, and system modeling approaches; (4) development of geometric models that simulate complex sky obstruction, incoming solar radiation for complex topographic surfaces, and the coupling of incoming solar radiation with energy and water balance, with simulations of incoming solar radiation for selected native vegetation and experimental waste cover design sites; and (5) evaluation of the strengths and limitations of the various field sampling techniques. The second study describes an approach to develop software that takes advantage of new generation computers to model insolation on complex topographic surfaces. SOLARFLUX is a GIS-based (ARC/INFO, GRID) computer program that models incoming solar radiation based on surface orientation (slope and aspect), solar angle (azimuth …
Date: December 31, 1994
Creator: Rich, P. M.; Hetrick, W. A. & Saving, S. C.
Object Type: Report
System: The UNT Digital Library
Chemical and electrical properties of cavities in silicon and germanium (open access)

Chemical and electrical properties of cavities in silicon and germanium

Cavities were formed in Si and Ge by He ion implantation and annealing, and resultant chemical and electrical properties were investigated. The dissociation energies for Si-H and Ge-H surface monohydride bonds were determined, showing that H chemisorption on Si is energetically stable with respect H{sub 2} gas whereas H chemisorption on Ge is not. Cavity walls in Si were found to trap transition metals strongly, suggesting application to impurity gettering in devices. Measurement and modeling of cavity electrical properties elucidated surface electronic states and indicated a potential for controlled electrical isolation in devices. 35 refs.
Date: December 31, 1994
Creator: Myers, S. M.; Follstaedt, D. M.; Petersen, G. A.; Seager, C. H.; Stein, H. J. & Wampler, W. R.
Object Type: Report
System: The UNT Digital Library
Chemically bonded phosphate ceramics for low-level mixed waste stabilization (open access)

Chemically bonded phosphate ceramics for low-level mixed waste stabilization

Novel chemically bonded phosphate ceramics (CBPCs) are being developed and fabricated for low-temperature stabilization and solidification of mixed waste streams which are amenable to conventional high-temperature stabilization processes due to presence of volatiles such as heavy metal chloride and fluorides and/or pyrophorics in the wastes. Phosphates of Mg, Mg-Na and Zr are being developed as candidate matrix materials. In this paper, we present the fabrication procedures of phosphate waste forms using surrogates compositions of three typical mixed wastes streams -- ash, cement sludges, and salts. The performance of the final waste forms such as compression strength, leachability of the contaminants, durability in aqueous environment were conducted. In addition, parameteric studies have been conducted to establish the optimal waste loading in a particular binder system. Based on the results, we present potential applications in the treatment of various mixed waste streams.
Date: December 31, 1994
Creator: Singh, D.; Wagh, A. S.; Cunnane, J. C. & Mayberry, J. L.
Object Type: Report
System: The UNT Digital Library
Chemistry of spring and well waters on Kilauea Volcano, Hawaii, and vicinity (open access)

Chemistry of spring and well waters on Kilauea Volcano, Hawaii, and vicinity

Published and new data for chemical and isotopic samples from wells and springs on Kilauea Volcano and vicinity are presented. These data are used to understand processes that determine the chemistry of dilute meteoric water, mixtures with sea water, and thermal water. Data for well and spring samples of non-thermal water indicate that mixing with sea water and dissolution of rock from weathering are the major processes that determine the composition of dissolved constituents in water. Data from coastal springs demonstrate that there is a large thermal system south of the lower east rift of Kilauea. Samples of thermal water from shallow wells in the lower east rift and vicinity have rather variable chemistry indicating that a number of processes operate in the near surface. Water sampled from the available deep wells is different in composition from the shallow thermal water, indicating that generally there is not a significant component of deep water in the shallow wells. Data for samples from available deep wells show significant gradients in chemistry and steam content of the reservoir fluid. These gradients are interpreted to indicate that the reservoir tapped by the existing wells is an evolving vapor-dominated system.
Date: December 31, 1994
Creator: Janik, Cathy J.; Nathenson, Manuel & Scholl, Martha A.
Object Type: Report
System: The UNT Digital Library
The Chickasha Star (Chickasha, Okla.), Vol. 93, No. 55, Ed. 1 Saturday, December 31, 1994 (open access)

The Chickasha Star (Chickasha, Okla.), Vol. 93, No. 55, Ed. 1 Saturday, December 31, 1994

Semiweekly newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: December 31, 1994
Creator: unknown
Object Type: Newspaper
System: The Gateway to Oklahoma History
Chiral limit of QCD (open access)

Chiral limit of QCD

This talk contains an analysis of quenched chiral perturbation theory and its consequences. The chiral behavior of a number of quantities such as the pion mass m{sub pi}{sup 2}, the Bernard-Golterman ratios R and {sub X}, the masses of nucleons, and the kaon B-parameter are examined to see if the singular terms induced by the additional Goldstone boson, {eta}{prime}, are visible in present data. The overall conclusion (different from that presented at the lattice meeting) of this analysis is that even though there are some caveats attached to the indications of the extra terms induced by {eta}{prime} loops, the standard expressions break down when extrapolating the quenched data with m{sub q} < m{sub s}/2 to physical light quarks. I then show that due to the single and double poles in the quenched {eta}{prime}, the axial charge of the proton cannot be calculated using the Adler-Bell-Jackiw anomaly condition. I conclude with a review of the status of the calculation of light quark masses from lattice QCD.
Date: December 31, 1994
Creator: Gupta, R.
Object Type: Article
System: The UNT Digital Library
Cleaning without chlorinated solvents (open access)

Cleaning without chlorinated solvents

Because of health and environmental concerns, many regulations have been passed in recent years regarding the use of chlorinated solvents. The Oak Ridge Y-12 Plant has had an active program to find alternatives for these solvents used in cleaning applications for the past 7 years. During this time frame, the quantity of solvents purchased has been reduced by 92%. The program has been a twofold effort. Vapor degreasers used in batch cleaning-operations have been replaced by ultrasonic cleaning with aqueous detergent, and other organic solvents have been identified for use in hand-wiping or specialty operations. In order to qualify these alternatives for use, experimentation was conducted on cleaning ability as well as effects on subsequent operations such as welding, painting and bonding. Cleaning ability was determined using techniques such as X-ray photoelectron spectroscopy (XPS) and Fourier Transform Infrared Spectroscopy (FTIR) which are capable of examining monolayer levels of contamination on a surface. Solvents have been identified for removal of rust preventative oils, lapping oils, machining coolants, lubricants, greases, and mold releases. Solvents have also been evaluated for cleaning urethane foam spray guns, swelling of urethanes and swelling of epoxies.
Date: December 31, 1994
Creator: Thompson, L.M. & Simandl, R.F.
Object Type: Article
System: The UNT Digital Library
CO{sub 2} exchange environmental productivity indices, and productivity of agaves and cacti under current and elevated atmospheric CO{sub 2} concentrations. Final report (open access)

CO{sub 2} exchange environmental productivity indices, and productivity of agaves and cacti under current and elevated atmospheric CO{sub 2} concentrations. Final report

The research described in the proposal investigated net CO{sub 2} uptake and biomass accumulation for an extremely productive CAM plant, the prickly pear cactus Opuntia ficus-indica, under conditions of elevated CO{sub 2} concentrations for relatively long periods. The influences of soil water status, air temperature, and the photosynthetic photon flux (PPF) on net CO{sub 2} uptake over 24-h periods were evaluated to enable predictions to be made based on an Environmental Productivity Index (EPI). Specifically, EPI predicts the fraction of maximal daily net CO{sub 2} uptake based on prevailing environmental conditions. It is the product of indices for temperature, soil water, and intercepted PPF, each of which range from 0.00 when that index factor completely inhibits net CO{sub 2} uptake to 1.00 when no limitation occurs. For instance, the Water Index is 1.00 under wet conditions and decreases to 0.00 during prolonged drought. Although the major emphasis of the research was on net C0{sub 2} uptake and the resulting biomass production for O. ficus-indica, effects of elevated CO{sub 2} concentrations on root: shoot ratios and on the activities of the two carboxylating enzymes were also investigated. Moreover, experiments were also done on other CAM plants, including Agave deserti, Agave salmiana, …
Date: December 31, 1994
Creator: Nobel, P.S.
Object Type: Report
System: The UNT Digital Library
Coal combustion: Effect of process conditions on char reactivity. Quarterly technical report, July 1, 1994--September 30, 1994 (open access)

Coal combustion: Effect of process conditions on char reactivity. Quarterly technical report, July 1, 1994--September 30, 1994

The project will quantify the effect of the following pyrolysis conditions on the macropore structure and on the subsequent reactivity of chars: (a) pyrolysis heating rate; (b) final heat treatment temperature (HTT); (c) duration of heat treatment at HTT (or soak time); (d) pyrolysis atmosphere (N{sub 2} or O{sub 2}/N{sub 2} mixtures); (e) coal particle size (100-1,000 {mu}m in diameter); (f) sulfur-capturing additives (limestone); and (g) coal rank. Pyrolysis experiments will be carried out for three coals from the Argonne collection: (1) a high-volatile bituminous coal with high ash content (Illinois {number_sign}6), (2) a bituminous coal with low ash content (Utah Blind Canyon) and (3) a lower rank subbituminous coal (Wyodak-Anderson seam). A mathematical model was developed to study the thermal ignition of char particles. The model assumes a bimodal pores size distribution with small micropores (of the order of a few {angstrom}) and large micropores in the {mu}m size range. All the model parameters can be estimated using data obtained previously in our laboratory. We are currently testing this model to determine its validity and to investigate how char properties (porosity, particle size, macropore surface area, micropore radius) and operating conditions (temperature, oxygen concentration, flow rate) affect ignition phenomena.
Date: December 31, 1994
Creator: Zygourakis, K.
Object Type: Report
System: The UNT Digital Library
Coal combustion: Effect of process conditions on char reactivity. Quarterly technical report, October 1, 1994--December 31, 1994 (open access)

Coal combustion: Effect of process conditions on char reactivity. Quarterly technical report, October 1, 1994--December 31, 1994

The project will quantify the effect of the following pyrolysis conditions on the macropore structure and on the subsequent reactivity of chars: (a) pyrolysis heating rate; (b) final heat treatment temperature (HTT); (c) duration of heat treatment at HTT (or soak time); (d) pyrolysis atmosphere (N{sub 2} or O{sub 2}/N{sub 2} mixtures); (e) coal particle size (100--1000 {mu}m in diameter); (f) sulfur-capturing additives (limestone); and (g) coal rank. Pyrolysis experiments will be carried out for three coals from the Argonne collection: (1) a high-volatile bituminous coal with high ash content (Illinois No. 6), (2) a bituminous coal with low ash content (Utah Blind Canyon) and (3) a lower rank subbituminous coal (Wyodak-Anderson seam). A systematic parametric study was carried out in the past quarter to quantify the effect of different process parameters on the ignition phenomena. Using the mathematical model presented in the previous quarterly report, we investigated how char properties (porosity, particle size, macropore surface area, and micropore radius) and operating conditions (oxygen concentration, flow rate) affect ignition phenomena. In every case, we clearly identified the temperature range in which thermal ignitions may be expected. Model predictions will next be compared to experimental results to validate our theoretical model.
Date: December 31, 1994
Creator: Zygourakis, K.
Object Type: Report
System: The UNT Digital Library
Coal liquefaction model compounds. Final report, September 1, 1992--August 31, 1994 (open access)

Coal liquefaction model compounds. Final report, September 1, 1992--August 31, 1994

This final report is divided into sections dealing with tetralin pyrolysis, chroman pyrolysis, molecular mechanics of organometallic systems, and pi conjugated biradicals. Experiments performed and results are discussed for each area of study.
Date: December 31, 1994
Creator: Gajewski, J.J. & Gilbert, K.E.
Object Type: Report
System: The UNT Digital Library