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Linkage of anthropogenic aerosol to clouds and climate. Final report

Description: Work performed between July 1991 and June 1994 is very briefly summarized in this report. The work done concerns differences between clouds and the aerosol particles, or cloud condensation nuclei (CCN), upon which the cloud droplets condense. In particular, the substantial contribution of anthropogenic sources to CCNs and their effects on clouds were examined. Ship board measurements of CCN concentrations in clouds were taken in July 1991. In June 1992, aircraft measurements and analyses of CCN concentrations showed substantial influences of anthropogenic aerosol on clouds through long-range transport of polluted air. A June 1994 study indicated that CCN produced by ships caused ship trail clouds even in moderately polluted clouds.
Date: November 1997
Creator: Hudson, J. G.
Partner: UNT Libraries Government Documents Department

Modeling the wind-fields of accidental releases with an operational regional forecast model

Description: The Atmospheric Release Advisory Capability (ARAC) is an operational emergency preparedness and response organization supported primarily by the Departments of Energy and Defense. ARAC can provide real-time assessments of atmospheric releases of radioactive materials at any location in the world. ARAC uses robust three-dimensional atmospheric transport and dispersion models, extensive geophysical and dose-factor databases, meteorological data-acquisition systems, and an experienced staff. Although it was originally conceived and developed as an emergency response and assessment service for nuclear accidents, the ARAC system has been adapted to also simulate non-radiological hazardous releases. For example, in 1991 ARAC responded to three major events: the oil fires in Kuwait, the eruption of Mt. Pinatubo in the Philippines, and the herbicide spill into the upper Sacramento River in California. ARAC`s operational simulation system, includes two three-dimensional finite-difference models: a diagnostic wind-field scheme, and a Lagrangian particle-in-cell transport and dispersion scheme. The meteorological component of ARAC`s real-time response system employs models using real-time data from all available stations near the accident site to generate a wind-field for input to the transport and dispersion model. Here we report on simulation studies of past and potential release sites to show that even in the absence of local meteorological observational data, readily available gridded analysis and forecast data and a prognostic model, the Navy Operational Regional Atmospheric Prediction System, applied at an appropriate grid resolution can successfully simulate complex local flows.
Date: September 11, 1995
Creator: Albritton, J.R.; Lee, R.L. & Sugiyama, G.
Partner: UNT Libraries Government Documents Department

Aerosol can puncture device test report

Description: This test report documents the evaluation of an aerosol can puncture device to replace a system currently identified for use in the WRAP-1 facility. The new system is based upon a commercially available puncture device, as recommended by WHC Fire Protection. With modifications found necessary through the testing program, the Aerosol Can Puncture Device was found able to puncture and drain aerosol cans without incident. Modifications include the addition of a secondary collection bottle and the modification of the can puncture needle. In the course of testing, a variety of absorbents were tested to determine their performance in immobilizing drained fluids. The visibility of the puncture with Non-Destructive Examination techniques were also reviewed.
Date: October 1, 1994
Creator: Leist, K. J.
Partner: UNT Libraries Government Documents Department

Environmental surveillance at Los Alamos during 1995

Description: This report describes the environmental surveillance program at Los Alamos National Laboratory (LANL or the Laboratory) during 1995. The Laboratory routinely monitors for radiation and for radioactive and nonradioactive materials at (or on) Laboratory sites as well as in the surrounding region. LANL uses the monitoring result to determine compliance with appropriate standards and to identify potentially undesirable trends. Data were collected in 1995 to assess external penetrating radiation; quantities of airborne emissions and liquid effluents; concentrations of chemicals and radionuclides in ambient air, surface waters and groundwaters, municipal water supply, soils and sediments, and foodstuffs; and environmental compliance. Using comparisons with standards, regulations, and background levels, this report concludes that environmental effects from Laboratory operations are small and do not pose a demonstrable threat to the public, Laboratory employees, or the environment.
Date: October 1, 1996
Partner: UNT Libraries Government Documents Department

Low density inorganic foams fabricated using microwaves

Description: The objective of our work was to determine if high temperature foams could be made using microwave heating; and if so, to investigate some of their properties. Several foams were made and their compressive strengths, tensile strengths and densities were determined. Foams were made of glass, metal-glass, glass-fiber, metal-glass-fiber, and fly ash. The microwave source used was a Litton model 1521 microwave oven which operated at 2.45 GHz and had an output of 700 watts.
Date: January 1, 1985
Creator: Meek, T.T.; Blake, R.D. & Gregory, T.G.
Partner: UNT Libraries Government Documents Department

Emissions model of waste treatment operations at the Idaho Chemical Processing Plant

Description: An integrated model of the waste treatment systems at the Idaho Chemical Processing Plant (ICPP) was developed using a commercially-available process simulation software (ASPEN Plus) to calculate atmospheric emissions of hazardous chemicals for use in an application for an environmental permit to operate (PTO). The processes covered by the model are the Process Equipment Waste evaporator, High Level Liquid Waste evaporator, New Waste Calcining Facility and Liquid Effluent Treatment and Disposal facility. The processes are described along with the model and its assumptions. The model calculates emissions of NO{sub x}, CO, volatile acids, hazardous metals, and organic chemicals. Some calculated relative emissions are summarized and insights on building simulations are discussed.
Date: March 1, 1995
Creator: Schindler, R.E.
Partner: UNT Libraries Government Documents Department

Environmental aspects of cooling tower operation: survey of the emission, transport, and deposition of drift from the K-31 and K-33 cooling towers at ORGDP

Description: The results from a program ulo evaluaule the environmental aspeculs of cooling ulower operation at the Oak Ridge Gaseous Diffusion Plan (ORGDP) are presented. The quantities of chemicals being introduced into the atmosphere as well as the deposition of these chemicals on the environs surrounding the cooling towers were measured. Based on the tests performed, the cooling towers, under present operating conditions, are noul causing any adverse effect on the native vegetation surrounding ORGDP. (auth)
Date: February 1, 1974
Creator: Jallouk, P.A.; Kidd, G.J. Jr. & Shapiro, T.
Partner: UNT Libraries Government Documents Department

Evaluation of EPA method 5 probe deposition and filter media efficiency. [Air sampler evaluation]

Description: In the process of development of an improved extractive stack sampler, EPA Method 5 was evaluated to quantitate probe deposition and efficiency of several glass fiber filters accepted by the method. Monodisperse fluorescing dye aerosols from 0.6 to 4.4 ..mu..m geometric diameter were generated from a vibrating orifice aerosol generator. Collection efficiencies against these aerosols were measured for MSA 1106 BH, Reeve-Angel 934AH, and Whatman GF/A and GF/C glass fiber filters at operating velocities of 5.2 and 10.3 cm/s. Efficiencies of these four filters were comparable, ranging from 99.6 to 99.8 percent against the 0.6 ..mu..m aerosol, to above 99.9 percent for aerosols larger than 1.0 ..mu..m. Probe deposition of a large (13.4 ..mu..m mass median diameter) glass bead aerosol was 94 percent, with approximately half occurring in the nozzle. Probe deposition of a 2.0 ..mu..m fly ash aerosol was 10.5 percent, again with approximately half deposited in the nozzle. Only 1.5 percent of a 1.2 ..mu..m dye aerosol deposited in the probe. These measurements emphasize the importance of consistent probe washing procedures, lower gas velocity in the nozzle, fewer bends and diameter changes, and smoother transition between probe components in the design of an improved sampler.
Date: January 1, 1977
Creator: Elder, J. C.; Tillery, M. E. & Ettinger, H. J.
Partner: UNT Libraries Government Documents Department

Development of the Nested Fiber Filter

Description: Battelle, has tested the Nested Fiber Filter (NFF) as a particulate control device for high temperature, high-pressure (HTHP) applications. Battelle funded initial bench-scale tests which were the basis for patents and a concept applying the NFF. Subsequent parametric tests in a 6-inch diameter reactor established excellent particulate capture performance, > 99 percent, for conditions up to 1600 F and 6 atmospheres. Effective cleaning/regeneration of the NFF was achieved in the 6-inch scale with acoustic and mechanical vibration. A pulse combustor was tested in an integrated NFF arrangement because of compatibility with the HTBP conditions. This arrangement provided the basis for larger scale tests under the subject contract. A 6-ft[sup 2] test module was designed and installed with an existing fluidized bed combustor for additional development and testing.
Date: January 1, 1992
Creator: Litt, R.D.; Conkle, H.N. & Raghavan, J.K.
Partner: UNT Libraries Government Documents Department

Flue gas conditioning for improved particle collection in electrostatic precipitators

Description: Several tasks have been completed in a program to evaluate additives to improve fine particle collection in electrostatic precipitators. Screening tests and laboratory evaluations of additives are summarized in this report. Over 20 additives were evaluated; four were found to improve flyash precipitation rates. The Insitec particle analyzer was also evaluated; test results show that the analyzer will provide accurate sizing and counting information for particles in the size range of [le] 10 [mu]m dia.
Date: April 16, 1993
Creator: Durham, M.D.
Partner: UNT Libraries Government Documents Department

High performance cyclone development

Description: The results of cold flow experiments at atmospheric conditions of an air-shielded 18 in-dia electrocyclone with a central cusped electrode are reported using fine test dusts of both flyash and nickel powder. These results are found to confirm expectations of enhanced performance, similar to earlier work on a 12 in-dia model. An analysis of the combined inertial-electrostatic force field is also presented which identifies general design goals and scaling laws. From this, it is found that electrostatic enhancement will be particularly beneficial for fine dusts in large cyclones. Recommendations for further improvement in cyclone collection efficiency are proposed.
Date: January 1, 1981
Creator: Giles, W.B.
Partner: UNT Libraries Government Documents Department

Optical properties of fly ash

Description: This task is planned to provide the basic optical properties data in a comprehensive and conveniently usable form. The optical constants (i.e., the components of the complex refractive index m = n - ik) of samples of synthetic slags of controlled compositions will be measured using established techniques involving transmission and surface reflectance methods. The wavelength range will extend from the visible to 12 {mu}m and the temperature range will extend to 2000K. Initially, the optical constants of the basic calcium-aluminosilicate host glass will be determined for the composition range defined by Task 1. Subsequently, by adding infrared-active mineral oxide constituents in controlled amounts, one at a time, the modifications to m({Lambda}, T) produced by such constituents will be quantitatively determined. The particular constituents (and their range of mass fractions) to be examined will be determined by those disclosed by Task 1, taking account of knowledge of the optical activity at relevant wavelengths of such additions from the literature of glass technology. Specific constituents to be examined will include Fe{sub 2}O{sub 3}, taking especial account of its valence state (Fe{sup 2+}/Fe{sup 3+} ratio), and of TiO{sub 2}. The contribution of the OH radical to the optical properties will be evaluated and quantified if significant. The experimental data on m({Lambda},T) as a function of composition, over the range relevant to coal ashes, will be reduced to generate simple correlation formulae. The latter will constitute the data base necessary to calculate the radiative properties of bulk slags and ash dispersions required for understanding and computing radiative transfer in coal combustion systems.
Date: July 1, 1988
Creator: Self, S.A.
Partner: UNT Libraries Government Documents Department

Optical properties of flyash

Description: The chemical composition and size distribution of representative flyashes are being measured by appropriate microanalytical techniques to provide information required. Measurements of the infrared optical constants (i.e., the complex refractive index m = n - ik) of synthetic slags are being made as a function of wavelength and temperature for controlled compositions. Particular attention will be given to the contribution of the Fe{sub 2}O{sub 3} content and its valence state. The data is being reduced to yield formulae giving the complex refractive index over relevant ranges of wavelength and temperature, as a function of the relevant metal oxide constituents. A benchscale experiment is planned to compare the measured radiant properties of a dispersion of well-characterized ash with computations based on data developed under the first two tasks.
Date: July 1, 1990
Creator: Self, S.A.
Partner: UNT Libraries Government Documents Department

Optical properties of flyash

Description: The purpose of this task is to validate the whole approach adopted in this program. Specifically, this bench-scale experiment is intended to compare the measured optical/radiative properties of a dispersion of well characterized ash with those calculated on the basis of the known size/composition distribution using the correlation formulae relating the composition and complex refractive index resulting from measurements on bulk samples of synthetic slag. Considerable thought has been given to the various possible approaches to satisfying the objectives of this task. Several experiments were done to guide our design of an apparatus for measuring the scattering and absorption properties of dispersions of flyash. As a result of these experiments, and from extensive prior experience in connection with research on electrostatic precipitation, it has been determined that there is no satisfactory way to satisfy the aims of this task using a gaseous dispersion of flyash because it is not possible to adequately disperse and deagglomerate flyash into a gas stream. Unless the ash is adequately dispersed, as it exists in the radiant boiler of a pulverized coal-fired combustion system, one cannot expect calculations, based on Mie calculations for a dispersion of spheres to properly agree with laboratory measurements. For these reasons, our design efforts are based on making measurements on a dispersion of flyash in liquid, for which our experience shows we can obtain stable, well-deagglomerated dispersions of ash. Because there is not single liquid which is adequately transparent over the wavelength range 1--12 {mu}m, we plan to use a combination of three liquids, C Cl{sub 4}, C S{sub 2} and bromoform to cover the full range. Windows of BaF{sub 2} will be used to contain the liquid suspension in an absorption/scattering cell.
Date: July 1, 1989
Creator: Self, S.A.
Partner: UNT Libraries Government Documents Department

Potential products from North Dakota lignite fly ash. Final report

Description: Four major areas where fly ash can be used are explored. Concrete building blocks with fly ash replacing 50% of the portland cement have proven to be successful using current ASTM standards. Results in the ceramics area show that a ceramic-like product using fly ash and crushed glass with a small amount of clay as a green binder. Some preliminary results using sulfur ash in building materials are reported and with results of making wallboard from ash. (MHR)
Date: June 1, 1980
Creator: Anderson, G R
Partner: UNT Libraries Government Documents Department

Characterization of fly ash from coal combustion

Description: Fly ash derived from coal combustion contains predominantly spherical particles which consist of an insoluble aluminosilicate glass containing several mineral impurities. An outer layer, 50 to 300 A thick, is rich in many potentially toxic trace elements in the form of simple and complex sulfates. This layer, which is soluble in water, contains essentially all of the particulate sulfur present in fly ash in the form of sulfate. The actual mechanism(s) of formation of particulate sulfate salts are ill-defined but probably involve adsorption of condensation of gaseous sulfur species onto fly ash surfaces within the power plant stack system.
Date: January 1, 1978
Creator: Natusch, D. F.S.
Partner: UNT Libraries Government Documents Department

Multinuclear NMR approach to coal fly ash characterization

Description: This report describes the application of various nuclear magnetic resonance (NMR) techniques to study the hydration kinetics and mechanisms, the structural properties, and the adsorption characteristics of coal fly ash. Coal fly ash samples were obtained from the Dave Johnston and Laramie River electric power generating plants in Wyoming. Hydrogen NMR relaxation times were measured as a function of time to observe the kinetics of hydration for the two coal fly ashes at different temperatures and water-to-cement ration. The kinetic data for the hydrated coal fly ashes were compared to the hydration of portland cement. The mechanism used to describe the kinetic data for the hydration of portland cement was applied, with reservation, to describe the hydration of the coal fly ashes. The results showed that the coal fly ashes differ kinetically from that of portland cement and from each other. Consequently, both coal fly ashes were judged to be poorer cementitious materials than portland cement. Carbon-13 NMR CP/MAS spectra were obtained for the anhydrous coal fly ashes in an effort to determine the type of organic species that may be present, either adsorbed on the surface or entrained.
Date: September 1, 1991
Creator: Netzel, D.A.
Partner: UNT Libraries Government Documents Department

Pulsed electron beam precharger

Description: During the previous reporting period (Quarter Six), the charging and removal of a fine, high resistivity aerosol using the advanced technology of electron beam precipitation was successfully accomplished. Precharging a dust stream circulating through the EBP wind tunnel produced collection efficiency figures of up to 40 times greater than with corona charging and collection alone (Table 1). The increased system collection efficiency attributed to electron beam precharging was determined to be the result of increased particle charge. It was found that as precharger electric field was raised, collection efficiency became greater. In sequence, saturation particle charge varies with the precharger electric field strength, particle migration velocity varies with the precharger and collector electric field, and collection efficiency varies with the migration velocity. Maximizing the system collection efficiency requires both a high charging electric field (provided by the E-beam precharger), and a high collecting electric field (provided by the collector wires and plates). Because increased particle collection efficiency is directly attributable to higher particle charge, the focus of research during Quarter Seven was shifted to learning more about the actual charge magnitude on the aerosol particles. Charge determinations in precipitators have traditionally been made on bulk dust samples collected from the flue gas stream, which gives an overall charge vs. mass (Q/M) ratio measurement. More recently, techniques have been developed which allow the measurement of the charge on individual particles in a rapid and repeatable fashion. One such advanced technique has been developed at FSU for use in characterizing the electron beam precharger.
Date: January 1, 1991
Creator: Finney, W.C. (ed.) & Shelton, W.N.
Partner: UNT Libraries Government Documents Department

Pulsed electron beam precharger

Description: Quarter Eight of the Pulsed Electron Precharging project was principally devoted to the operation of the E-beam precharger in the pulsed anode mode. We shall first briefly review the motivation for carrying out this project and the experimental approach used. The combustion of low sulfur coal for the purpose of generating electric energy in power plants results in the production of a flue gas containing very high resistivity fly ash. This fly ash is not easily collected by conventional electrostatic precipitators due to the large electric potential difference which develops across the layer of fly ash on the collector plate. If this layer of collected material is allowed to reach a thickness as great as is normally desirable before rapping'' the plates, then the collected fly ash is subject to re-entrainment into the flue gas stream due to back-corona. The back-corona corona problem is described more fully in the next section of this report. This re-entrainment problem can be eliminated through reduction of the voltage applied across the high voltage wires and the grounded plates of the electrostatic precipitator. This is not a good solution to the problem since the charging capability and collection efficiency of the precipitator system are both greatly reduced at the low voltages required to avoid the back-corona problem. Another approach to solving the problems inherent in collecting high resistivity fly ash in an electrostatic precipitator is to decouple the charging and collecting functions. At FSU an electron beam precharger is employed directly before (upstream in the flue gas pathway) the precipitator. This precharger can be optimized for the charging function while the downstream collector can be optimized for collection of the high-resistivity fly ash.
Date: January 1, 1991
Creator: Finney, W.C. (ed.) & Shelton, W.N.
Partner: UNT Libraries Government Documents Department

Fly ash from Texas lignite and western subbituminous coal: a comparative characterization

Description: As examples, we use two Jackson group lignites from Atascosa and Fayette Counties, Texas, and a Green River Region subbituminous coal from Routt County, Colorado. The composition of individual fly ash particles was determined using scanning electron microscopy and electron microprobe, with support from x-ray diffraction of bulk ash. Using particle sample populations large enough to permit statistical treatment, we describe the relationship of composition to particle size and the correlation between elemental concentrations, as well as particle size and composition distributions. Correlations are displayed as data maps which show the complete range of observed variation among these parameters, emphasizing the importance of coal variability. We next use this data to produce a population distribution of ash particle resistivities calculated with Bickelhaupt's model. The relationship between calculated resistivity and particle size is also displayed, and the results are compared with measured values. 7 figures.
Date: January 1, 1982
Creator: Sears, D. R.; Benson, S. A.; McCollor, D. P. & Miller, S. J.
Partner: UNT Libraries Government Documents Department

Use of fast-neutron activation analysis for the determination of the silicon content in coal, flyash, and soil

Description: The values of the silicon content and the associated precisions obtained for the samples analyzed in this study are listed. It was the purpose of this study to employ fast neutron activation analysis for the determination of silicon content in coal, flyash, and soil. The silicon content of coal, flyash, and soil samples have been obtained with accuracies and precisions in good agreement with the accuracies and precisions reported by other researchers performing similar analyses. Terramethylsilane was found to be a suitable standard for this study. Finally, careful sample packaging and handling techniques were found to be crucial for obtaining accurate and precise results. It can be concluded that fast neutron activation analysis using the system at the University of Illinois can be used successfully to determine silicon content.
Date: January 1, 1982
Creator: Chan, K. K.
Partner: UNT Libraries Government Documents Department

Energy and solid/hazardous waste

Description: This report addresses the past and potential future solid and hazardous waste impacts from energy development, and summarizes the major environmental, legislation applicable to solid and hazardous waste generation and disposal. A glossary of terms and acronyms used to describe and measure solid waste impacts of energy development is included. (PSB)
Date: December 1, 1981
Partner: UNT Libraries Government Documents Department

Particulate processes in pulverized coal flames. Quarterly technical progress report, October-December 1980

Description: Major attention has been focused on the design and construction of the experiment. The design of two dilute coal stream reactor heads was completed as was the fabrication of one of the reactor heads. A parametric analysis of furnace design was conducted to allow operating conditions and insulation configurations to be selected to provide an axial temperature drop of less than 200/sup 0/K/m with a 1-second residence time in the reactor. Final design of the reactor body is in progress. Design of the instrumentation interface with the experiment was initiated. Emphasis has been placed on reactants metering and interface requirements for frontlight and backlight holography. Fabrication of the gas phase reactants metering system is in progress as are exploratory studies of particulate phase metering systems.
Date: January 1, 1981
Partner: UNT Libraries Government Documents Department