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Coal liquefaction and gas conversion: Proceedings. Volume 2
Volume II contains papers presented at the following sessions: Indirect Liquefaction (oxygenated fuels); and Indirect Liquefaction (Fischer-Tropsch technology). Selected papers have been processed separately for inclusion in the Energy Science and Technology Database.
Date:
December 31, 1993
Creator:
unknown
Object Type:
Article
System:
The UNT Digital Library
Coal liquefaction process streams characterization and evaluation: An analytical characterization case study
Deactivation of the second-stage supported catalyst dominated most of the properties over the course of the run. Consequences of increased catalyst age were increases in aromaticity and phenolic -OH concentration and decreases in hydrogen donor content and paraffinic hydrogen content in most process streams, including product distillates. Donor solvent quality of the whole PFL increased through the early part of the run until Period 8 when it apparently stabilized. The properties of the net product oil and its distillate fractions, as determined by NIPER, show that the coal-derived material has some desirable qualities. The whole crude has a low sulfur content and boils below the maximum temperature allowed for the production of transportation fuels. The naphtha fraction (IBP-380{degrees}F) is highly naphthenic and has a low benzene content. The naphtha fraction appears to be amenable to mild hydrotreating to produce a good gasoline blendstock. The kerosene (380--510{degrees}F) fraction is much too cyclic for use as aviation fuel and it is recommended that this fraction be distributed into the two cuts on either end of it (diesel and gasoline feedstocks). The 510--680{degrees}F fraction met most specifications as a heating fuel and diesel fuel. It appears that this material, after moderate hydroprocessing, could …
Date:
December 31, 1993
Creator:
Brandes, S. D.; Robbins, G. A.; Winschel, R. A. & Burke, F. P.
Object Type:
Article
System:
The UNT Digital Library
Coal-water slurry spray characteristics of an electronically-controlled accumulator fuel injection system
Experiments have been complete to characterize coal-water slurry sprays from a electronically-controlled accumulator fuel injection system of diesel engine. The sprays were injected into a pressurized chamber equipped with windows. High speed movies, fuel pressures and needle lifts were obtained as a function of time, orifice diameter, coal loading, gas density in the chamber, and accumulator fuel pressure. For the base conditions 50% (by mass) coal loading, 0.4 mm diameter nozzle hole, coal-water slurry pressure of 82 MPa (12,000 psi), and a chamber density of 25 kg/m{sup 3}, the break-up time was 0. 30 ms. An empirical correlation for both spray tip penetration and initial jet velocity was developed. For the conditions of this study, the spray tip penetration and initial jet velocity were 15% greater for coal-water slurry than for diesel fuel or water. Cone angles of the sprays were dependent on the operating conditions and fluid, as well as the time and locations of the measurement. The time-averaged cone angle for the base case conditions was 13.6{degree}. Results of this study and the correlation are specific to the tested coal-water slurry and are not general for other coal-water slurry fuels.
Date:
December 31, 1993
Creator:
Caton, J. A.; Payne, S. E.; Terracina, D. P. & Kihm, K. D.
Object Type:
Article
System:
The UNT Digital Library
Coal-water slurry sprays from an electronically controlled accumulator fuel injection system: Break-up distances and times
Experiments have been completed to characterize coal-water slurry sprays from an electronically-controlled accumulator fuel injection system of a diesel engine. The sprays were injected into a pressurized chamber equipped with windows. High speed movies, fuel pressures and needle lifts were obtained as a function of time, orifice diameter, coal loading, gas density in the chamber, and accumulator fuel pressure. For the base conditions (50% (by man) coal loading, 0.4 mm diameter nozzle hole, coal-water slurry pressure of 82 MPa (12,000 psi), and a chamber density of 25 kg/m{sup 3}), the break-up time was 0.30 ms. An empirical correlation for spray tip penetration, break-up time and initial jet velocity was developed. For the conditions of this study, the spray tip penetration and initial jet velocity were 15% greater for coal-water slurry than for diesel fuel or water. Results of this study and the correlation are specific to the tested coal-water slurry and are not general for other coal-water slurry fuels.
Date:
December 31, 1993
Creator:
Caton, J. A.; Payne, S. E.; Terracina, D. P. & Kihm, K. D.
Object Type:
Article
System:
The UNT Digital Library
Coaxial Slow Source. Final technical report, November 16, 1991--November 15, 1993
This report describes work performed by the University of Washington Aerospace and Energetics Research Program involving the Field Reversed Configuration (FRC) approach to magnetic confinement fusion. The group`s effort involved continued research on the Coaxial Slow Source annular FRC experimental device located on campus, as well as support for the Large s Experiment (LSX) operated by Spectra Technology Incorporated, Bellevue, Washington.
Date:
December 31, 1993
Creator:
Brooks, R. D. & Jarboe, T. R.
Object Type:
Report
System:
The UNT Digital Library
Code development incorporating environmental, safety and economic aspects of fusion reactors; Annual progress report
This document is a proposal to continue the authors work on the Environmental, Safety and Economic (ESE) aspects of fusion reactors under DOE contract DE-FR03-89ER52514. The grant objectives continue those from the previous grant: (1) completion of first-generation Environmental, Safety and Economic (ESE) computer modules suitable as integral components of tokamak systems codes. (2) continuation of work on special topics, in support of the above and in response to OFE requests. The proposal also highlights progress on the contract in the twelve months since April, 1992. This has included work with the ARIES and ITER design teams, work on tritium management, studies on materials activation, and calculation of radioactive inventories in fusion reactors.
Date:
December 31, 1993
Creator:
Fowler, T.K.; Greenspan, E. & Holdren, J.P.
Object Type:
Report
System:
The UNT Digital Library
Coherence and chaos
The annihilation operator for harmonic oscillator is a weighted shift operator and can be realized on a family of over complete coherent states. Shift operators arise in dynamical maps of systems exhibiting deterministic chaos. Generalized coherent states, called harmonious states, realize these maps in a simple manner. By analytic continuation the spectral family can be altered, thus furnishing an alternative perspective on resonant scattering. Singular distributions are necessary to reproduce the rich structure of chaotic and scattering systems.
Date:
December 31, 1993
Creator:
Sudarshan, E. C. G.
Object Type:
Article
System:
The UNT Digital Library
Coherent Compton X-ray sources
Coherent X-Rays can be produced by scattering of laser light by a beam of relativistic electrons, provided that the electron beam is density modulated or the scattering is done at, or near 90{degree}. Since the coherent scattering is proportional to N{sup 2}, where N is the number of electrons, and the incoherent scattering is proportional to N, also a modest degree of coherence can substantially increase the X-Ray yield. The theory of laser-electron beam scattering is reviewed and compared with the emission of radiation by an electron beam in an undulator. Examples of the practical implementation of an intense source of coherent X-Rays are discussed.
Date:
December 31, 1993
Creator:
Luccio, A. & Miceli, L.
Object Type:
Article
System:
The UNT Digital Library
Cold Cluster Ferromagnetism
We examine the magnetic moment distribution of ferromagnetic clusters under conditions where the magnetic moment is aligned with the internal cluster axis. Analytic expressions are obtained for the moment distribution and the adiabatic average moment induced in low fields. The result differs from the low-field Langevin function by a factor 2/3.
Date:
December 31, 1993
Creator:
Bertsch, G. F. & Yabana, K.
Object Type:
Report
System:
The UNT Digital Library
Collapse of Flux Tubes
Flux tubes are one of the most elementary systems of quantum chromodynamics. They are the idealized configurations of heavy quark-antiquark pairs at large separations L such that the region between can be assumed to possess axial-cylindrical symmetry. They play a central role in lattice QCD calculations and in models of QCD, as well as in the phenomenology of QCD processes. Lattice QCD calculations on flux tubes are generally limited to the quenched approximation (no massless quarks) and allow for a separation of the heavy quark-antiquark of only about 1 fm. Static flux tubes are unstable at separations greater than 1 fm, since the energy required to stretch the tube by 1 fm is about 1 GeV and that is about the energy difference between a quarkonium, Q{bar Q}, and a pair of heavy-light mesons, Q{bar q} + {bar Q}q. Lattice calculations without light quarks cannot explore this instability. The author then reviews work on efforts to explore the creation of light quark pairs as a mechanism for flux tube breaking.
Date:
December 31, 1993
Creator:
Wilets, L.
Object Type:
Article
System:
The UNT Digital Library
Collective Thomson scattering measurements of the Ion Acoustic Decay Instability. Final report
We have developed an uv collective Thomson scattering system for plasma produced by a short wavelength laser. The Ion Acoustic Decay Instabilities are studied in a large ({approximately}mm) scale, hot ({approximately}keV) plasma, which is relevant to a direct-driven laser fusion plasma. The IADI primary decay process is measured by the CTS. We used a random phase plate to minimize the non uniform irradiation of the interaction laser. Nevertheless, the threshold of the most unstable mode driven by the IADI is quite low. The measured threshold value agrees favorably with the theoretical value of the large scale plasma. We have also shown that the CTS from the IADI can be a good tool for measuring a local electron temperature. The measured results agree reasonably with the SAGE computer calculations. We used the real part of the wave (frequency) to estimate T{sub e}. The real part is, in general, reliable compared to the imaginary part such as the damping, and the growth rates. We have shown that the IADI can be easily excited in a large scale, hot plasma. The IADI has potentially important applications to direct drive laser fusion, and also critical surface diagnostic.
Date:
December 31, 1993
Creator:
Mizuno, K.; DeGroot, J. S.; Drake, R. P. & Seka, W.
Object Type:
Report
System:
The UNT Digital Library
Colloid formation in copper-implanted fused silica and silicate glasses
Copper implantations (90 keV, 5{times}10{sup 16} ions/cm{sup 2}) were made into fused silica, borosilicate glasses and soda-lime glass. The copper distribution has been found to vary according to glass type. The optical absorption band characteristic of the implanted metal optical properties was observed only for copper-implanted fused silica. Absorption for all the other samples was either not observable or was negligibly small, however very small metallic particles are present also in soda-lime glass. Subsequent nitrogen implantation (100 keV, 1.5{times}10{sup 17} ions/cm{sup 2}) completely eliminated the copper-colloid induced absorption in the copper-implanted fused silica, while it facilitated formation of copper-colloids in soda-lime glass.
Date:
December 31, 1993
Creator:
Mazzoldi, P.; Caccavale, F. & Cattaruzza, E.
Object Type:
Article
System:
The UNT Digital Library
Combustion and emissions characterization of pelletized coal fuels. Final technical report, September 1, 1992--August 31, 1993
The feasibility of converting waste preparation plant coal streams into marketable fuels with good combustion and emissions properties has been investigated in this project. Coal pellets containing both hydrated lime and limestone as sorbents were made from a flotation column waste feedstock under a related Illinois Clean Coal Institute project. These pellets, which contain sorbent with Ca/S ratio varying from 0.8 to 2.4 were successfully burnt in a 4-inch internal diameter circulating fluidized bed combustor. Emissions levels of sulfur dioxide, oxides of nitrogen and hydrogen chloride were measured as a function of bed temperature. Mineral matter analyses of the combustion generated ash was made, and combustion efficiencies were studied. The pellet coals combustion performance was compared to that of an Illinois No. 6 run-of-mine coal from the same preparation plant. Results show that the coal pellets, produced from the flotation column waste stream, are excellent fluidized bed combustor fuels. Calcium hydroxide impregnated pellets yielded lower sulfur dioxide emissions than limestone sorbent pellets for the same Ca/S ratio. Increase in Ca/S ratio with the hydrated lime sorbent produced a more rapid decline in sulfur dioxide emissions than with the limestone sorbent. Oxides of nitrogen emissions were generally on the order of …
Date:
December 31, 1993
Creator:
Rajan, S.
Object Type:
Report
System:
The UNT Digital Library
Combustion properties of coal-char blends: NO{sub x} emission characteristics. Interim final technical report, September 1, 1992--August 31, 1993
Under pulverized coal combustion conditions, NO{sub x} formed during the release of volatile matter far exceed NO{sub x} formed from combustion of the resulting char. It is believed that interactions of NO{sub x} with char is responsible for the reduced NO{sub x} formation from the combustion of char. The goal of this research is to assess the potential technical and economical benefits of co-firing coal-char blends in pulverized coal boilers to reduce NO{sub x}. The rationale for the proposed research is that the presence of char in the flame during the initial stages of combustion may provide catalytic activity for reduction of NO{sub x} produced from volatile nitrogen. This project is a cooperative effort between the Illinois State Geological Survey (ISGS) and BYU/ACERC. Seven hundred and fifty pounds of three coal-char blends containing 12.5%, 25%, and 50% char and 125 pounds of a coal-activated carbon blend containing 12.5% activated carbon were prepared. The volatile matter contents of the blends ranged from 27.3 to 35.6% (dry basis). Char (16.2 wt% volatile matter) was made from an Illinois No. 6 coal (Peabody Coal Company) in a continuous feed charring oven under mild gasification conditions. Nine combustion tests will be performed with the …
Date:
December 31, 1993
Creator:
Rostam-Abadi, M.; Khan, L.; Khan, S.; Smoot, L. D.; Germane, G. J. & Eatough, C. N.
Object Type:
Report
System:
The UNT Digital Library
Commercial demonstration of the NOXSO SO{sub 2}/NO{sub x} removal flue gas cleanup system. Quarterly technical progress report No. 9, March 1--May 31, 1993
The NOXSO process is a dry, post-combustion flue gas treatment technology which uses a regenerable sorbent to simultaneously adsorb sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) from the flue gas of a coal-fired utility boiler. In the process, the SO{sub 2} is reduced to elemental sulfur and the NO{sub x} is reduced to nitrogen and oxygen. It is predicted that the process can economically remove 90% of the acid rain precursor gases from the flue gas stream in a retrofit or new facility. The objective of the NOXSO Demonstration Project is to design, construct, and operate a flue gas treatment system utilizing the NOXSO process at Ohio Edison`s Niles Plant Unit {number_sign}1. The effectiveness of the process will be demonstrated by achieving significant reductions in emissions of sulfur and nitrogen oxides. In addition, sufficient operating data will be obtained to confirm the process economics and provide a basis to guarantee performance on a commercial scale. Ohio Edison`s Niles Plant Unit {number_sign}1 generates 115 MW of electricity and 275,000 scfm of flue gas while burning 3.5% sulfur coal. The project is presently in the project definition and preliminary design phase. This phase was included in the project to allow …
Date:
December 31, 1993
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Commercial demonstration of the NOXSO SO{sub 2}/NO{sub x} removal flue gas cleanup system. Quarterly technical progress report No. 10, June 1--August 31, 1993
The NOXSO process is a dry, post-combustion flue gas treatment technology which uses a regenerable sorbent to simultaneously adsorb sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) from the flue gas of a coal-fired utility boiler. In the process, the SO{sub 2} is reduced to sulfur by-product (elemental sulfur, sulfuric acid, or liquid SO{sub 2}) and the NO{sub x} is reduced to nitrogen and oxygen. It is predicted that the process can economically remove 90% of the acid rain precursor gases from the flue gas stream in a retrofit or new facility. The objective of the NOXSO Demonstration Project is to design, construct, and operate a flue gas treatment system utilizing the NOXSO process at Ohio Edison`s Niles Plant Unit {number_sign}1. The effectiveness of the process will be demonstrated by achieving significant reductions in emissions of sulfur and nitrogen oxides. In addition, sufficient operating data will be obtained to confirm the process economics and provide a basis to guarantee performance on a commercial scale. The project is presently in the project definition and preliminary design phase. Data obtained during pilot plant testing which was completed on July 30, 1993 is being incorporated in the design of the commercial size …
Date:
December 31, 1993
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Commercial demonstration of the NOXSO SO{sub 2}/NO{sub x} removal flue gas cleanup system. Quarterly technical progress report No. 11, September 1--November 30, 1993
The NOXSO process is a dry, post-combustion flue gas treatment technology which uses a regenerable sorbent to simultaneously adsorb sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) from the flue gas of a coal-fired utility boiler. In the process, the SO{sub 2} is reduced to sulfur by-product and the NO{sub x} is reduced to nitrogen and oxygen. It is predicted that the process can economically remove 90% of the acid rain precursor gases from the flue gas stream in a retrofit or new facility. The objective of the NOXSO Demonstration Project is to design, construct, and operate a flue gas treatment system utilizing the NOXSO process. The effectiveness of the process will be demonstrated by achieving significant reductions in emissions of sulfur and nitrogen oxides. In addition, sufficient operating data will be obtained to confirm the process economics and provide a basis to guarantee performance on a commercial scale. The project is presently in the project definition and preliminary design phase. Data obtained during pilot plant testing which was completed on July 30, 1993 is being incorporated in the design of the commercial size plant. A suitable host site to demonstrate the NOXSO process on a commercial scale is …
Date:
December 31, 1993
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Commercialization of previously-wasted coal mine gob gas and coalbed methane
Enrichment of a gas stream with only one contaminant is a relatively simple process (depending on the contaminant) using available technology. Most of the gas separation technology developed to date addresses this problem. However, gob gas has a unique nature, consisting of five primary constituents, only one of which has any significant value. These constituents are: methane, nitrogen, oxygen, carbon dioxide and water vapor. Each of the four contaminants may be separated from the methane using existing technologies that have varying degrees of complexity and compatibility. However, the operating and cost effectiveness of the combined system is dependent on careful integration of the clean-up processes. In summary, the system design that is expected to be the most favorable from both technical and economic viewpoints is a facility consisting of (1) a PSA nitrogen rejection unit, (2) a catalytic combustion deoxygenation process, (3) an amine or membrane carbon dioxide removal system, and (4) a conventional dehydration unit, as depicted in Figure 1.
Date:
December 31, 1993
Creator:
Sakashita, B. J. & Deo, M. D.
Object Type:
Article
System:
The UNT Digital Library
Comparative studies of brain activation with MEG and functional MRI
The past two years have witnessed the emergence of MRI as a functional imaging methodology. Initial demonstrations involved the injection of a paramagnetic contrast agent and required ultrafast echo planar imaging capability to adequately resolve the passage of the injected bolus. By measuring the local reduction in image intensity due to magnetic susceptibility, it was possible to calculate blood volume, which changes as a function of neural activation. Later developments have exploited endogenous contrast mechanisms to monitor changes in blood volume or in venous blood oxygen content. Recently, we and others have demonstrated that it is possible to make such measurements in a clinical imager, suggesting that the large installed base of such machines might be utilized for functional imaging. Although it is likely that functional MRI (fMRI) will subsume some of the clinical and basic neuroscience applications now touted for MEG, it is also clear that these techniques offer different largely complementary, capabilities. At the very least, it is useful to compare and cross-validate the activation maps produced by these techniques. Such studies will be valuable as a check on results of neuromagnetic distributed current reconstructions and will allow better characterization of the relationship between neurophysiological activation and associated …
Date:
December 31, 1993
Creator:
George, J. S.; Aine, C. J.; Sanders, J. A.; Lewine, J. D. & Caprihan, A.
Object Type:
Article
System:
The UNT Digital Library
A comparison between two Monte Carlo codes on determination of transient chemical yields
Monte Carlo computer codes have been independently developed at several laboratories for performing calculations of radiolysis of water. The different codes involve a wide variety of models and related assumptions in treating the many physical and chemical processes that occur. Because few detailed aspects of such computations can be directly checked by experiment, it is important to make comparisons of various predicted microscopic distributions. This paper compares results obtained with codes developed at Lawrence Berkeley Laboratory and at Oak Ridge National Laboratory. Both codes were used to calculate the spatial distributions of various radical species in spurs along the tracks of energetic electrons. Similarities and differences in the results of this preliminary study are shown. Additional work is planned.
Date:
December 31, 1993
Creator:
Hamm, R. N.; Turner, J. E. & Chatterjee, A.
Object Type:
Article
System:
The UNT Digital Library
Comparison of distribution, abundance, and activities of deep subsurface microorganisms. Progress report, 1 September 1992--31 August 1993
This project has provided DOE with basic information on the abundance, distribution and activities of aerobic heterotrophs in subsurface sediments from the Southeastern Coastal Plain (Savannah River Site -- SRS) and the Western Rockies Intermountain (Idaho National Engineering Laboratory -- INEL) and Columbia Plateau (Hanford Site). We have developed a new replica plating technique for determining numbers of microaerophiles and facultatively hypoaerobic bacteria in subsurface sediment samples. We have applied the technique to vadose zone samples from INEL and Hanford (Data submitted to database at Investigator`s Meeting, Chelan, WA, September 1991). The replica planting data suggest that most of the aerobic heterotrophic bacteria isolated from these boreholes grow at in wide range of oxygen concentrations from full saturation to one or to percent of saturation. We have tested several INEL and Hanford isolates for growth rate and growth yield at both low and high oxygen concentration. All isolates grew equally well at both oxygen concentrations regardless of whether they were isolated under low or high oxygen concentrations.
Date:
December 31, 1993
Creator:
Ghiorse, W. C. & Madsen, E. L.
Object Type:
Report
System:
The UNT Digital Library
Comparison of old and new ICRP models for respiratory tract dosimetry
This paper examines the historical development and application of respiratory tract dosimetry models by the International Commission for Radiological Protection, ICRP, for health protection from inhaled radioactive aerosols. Three different models are discussed, those that were included in ICRP recommendations published in 1960 and 1979, and the new ICRP Publication 66. Basic features of these models are compared and contrasted. These features include model structure, sites and frequencies of particle deposition, processes and rates of clearance of the deposited material from the respiratory tract, and consideration of the parameters involved in these processes and how various factors can influence these parameters. All three models lead to the calculation of absorbed radiation doses with differing degrees of regional and local specificity. These calculations are achieved using different tools ranging from quick hand calculations to sophisticated computerized modeling approaches. A side-by-side review of these models indicates several important trends in respiratory tract dosimetry models, the most obvious of which is the increased complexity of each new model over the past 30+ years. These increases reflect both the increasing size of the knowledge base derived from studies in laboratory animals and in human subjects and the need for models more broadly applicable for …
Date:
December 31, 1993
Creator:
Boecker, B.B.
Object Type:
Report
System:
The UNT Digital Library
Comparison of oxygen and silicon induced reactions at 14.6 A{center_dot}GeV/c
Oxygen induced reactions have been studied with minimum bias as well as with central triggers. A recent comparison of pion production for {sup 197}Au + Au {sup 28}Si + Au central collisions has shown a possible A{sup 2/3} dependance for the projectile and an A{sup 1/3} dependance with the target nucleon number. We find for central {sup 16}O + Au collisions that the pion yield dose similarly scale. The K/{pi} ratio for central {sup 16}O + Au reactions is .16 {plus_minus} .01, very similar to the central K/{pi} ratio for the {sup 28}Si + Au reaction.
Date:
December 31, 1993
Creator:
Zachary, D. S. & Collaboration, E802
Object Type:
Article
System:
The UNT Digital Library
A comparison of phase change phenomena in CTH with experimental data
An estimate of the current state of the predictive capabilities of hydrocodes for impacts where phase changes may be important was made by simulating a series of experiments where zinc spheres impact thin zinc plates at 4 velocities. The experimental data was taken from Mullin, et al. and consisted of radiographs of the debris cloud and estimates of the momentum in the debris cloud along the velocity vector. The velocities ranged from 3.30 to 6.79 km/s indicating that the debris consists of solid/molten fragments to predominantly vapor phase material as the velocity increases. The simulations reveal that the CTH hydro can accurately predict the debris structure and momentum transfer for this class of impacts.
Date:
December 31, 1993
Creator:
Hertel, E. S., Jr.; McIntosh, R. L. & Patterson, B. C.
Object Type:
Report
System:
The UNT Digital Library