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Program summaries for 1979: environmental programs

Description: Progress in research is reported for the three Divisions and one Group. Current programs in the Atmospheric Sciences Division include major participation in the multilaboratory cooperative Multistate Power Production Pollution Study - Regional Acidity of Industrial Emissions (MAP3S-RAINE), involving both field and modeling studies related to power-plant produced atmospheric pollutants on a regional scale, the study of the meteorology of the coastal land-sea interface, including both field and analytical activities, and field and modeling studies of the exchange of momentum, heat, and water vapor between the atmosphere and the ocean. The Environmental Chemistry Division is engaged in a wide range of programs including the development of methodologies and practical instrumentation for the detection and measurement of a variety of atmospheric constituents at ambient levels in real time in the field and in the laboratory, development and measurement of atmospheric tracers at extremely low levels, theoretical, laboratory, and field studies of the formation and behavior of aerosol particulates, and studies of gaseous and particulate emissions at power plants and in stack plumes in the atmosphere. The programs in Oceanographic Sciences include studies on coastal transport and diffusion, primary production and utilization, food chain dynamics, and ecosystems analysis. Emphasis in the Land and Freshwater Environmental Sciences Group has been on the effects of acid rain caused by energy-related pollutants on field crops, microbiota, and forest and freshwater ecosystems. Studies of the effects of acidification on the biota and biological processes of freshwater lakes are reported. Areas in the eastern United States sensitive to acidification were evaluated and mapped in a field and library study. (JGB)
Date: December 1, 1979
Partner: UNT Libraries Government Documents Department

The EPRI Laboratory experiments at ANL. [Vaporization of core-concrete mixtures]

Description: The vaporization of core-concrete mixtures is being measured using a transpiration method. Mixtures of stainless steel, concrete (limestone or basaltic) and urania (doped with La/sub 2/O/sub 3/, SrO, BaO, and ZrO/sub 2/) are vaporized at 2150 - 2400 K from a zirconia crucible into flowing He - 6% H/sub 2/ gas. Up to 600 ppM H/sub 2/O is added to the gas to fix the partial molar free energy of oxygen in the range -420 kJ to -550 kJ. The fraction of the sample that is vaporized is determined by weight change and by chemical analyses on the condensates that are collected in an Mo condenser tube. The results are being used to test the thermodynemic data base and the underlying assumptions of computer codes used for prediction of release during the severe accident. 13 refs., 2 tabs.
Date: October 28, 1987
Creator: Roche, M.F.; Settle, J.L.; Leibowitz, L.; Johnson, C.E. & Ritzman, R.L.
Partner: UNT Libraries Government Documents Department

Low-rank coal thermal properties and diffusivity: Final report

Description: This project developed techniques for measuring thermal properties and mass diffusivities of low-rank coals and coal powders. Using the concept of volume averaging, predictive models have been developed for these porous media properties. The Hot Wire Method was used for simultaneously measuring the thermal conductivity and thermal diffusivity of both consolidated and unconsolidated low-rank coals. A new computer-interfaced experiment is presented and sample container designs developed for both coal powders and consolidated coals. A new mathematical model, based upon volume averaging, is presented for the prediction of these porous media properties. Velocity and temperature effects on liquid-phase dispersion through unconsolidated coal were determined. Radioactive tracer data were used to determine mass diffusivities. A new predictive mathematical model is presented based upon volume averaging. Vapor-phase diffusivity measurements of organic solvents in consolidated lignite coal are reported. An unsteady-state pressure response experiment with microcomputed-based data acquisition was developed to estimate dispersion coefficients through consolidated lignite coals. The mathematical analysis of the pressure response data provides the dispersion coefficient and the adsorption coefficient. 48 refs., 59 figs., 17 tabs.
Date: June 1, 1987
Creator: Ramirez, W.F.
Partner: UNT Libraries Government Documents Department

Coal Technology Program. Progress report for November 1977

Description: A block of Pittsburgh seam bituminous coal and a block of Wyodak subbituminous coal were pyrolyzed under reducing gas in support of in situ gasification. Information from previously completed block pyrolysis of bituminous coal under an argon atmosphere show that differences in evolved gas result from differences in heating rates. Compared to block pyrolysis at 0.3 C/sup 0//min, block pyrolysis at 3 C/sup 0//min produces less gas but gas with a higher heating value, yielding a higher overall pyrolysis gas efficiency in recovering coal heating value. Experimental work on the fracture toughness and tensile properties of steels that may be used for piping and pressure vessels in very large gasification systems continued. The toughness of quenched 2/sup 1///sub 4/ Cr-1 Mo steel simulating the surface of a 254 to 305 mm-thick plate was measured, and the differences in toughness and tensile properties following two temperature treatments were determined. Post-weld heat treatment effects were also characterized. All properties remained within the range for ASME SA 387, Grade 22, Class 2 material. Work on inspection techniques for ceramic and cermet coatings is being closed out by completing and updating reports in various draft stages. Work is underway to establish a program for testing coal feeders under development by DOE/FE. Jet Propulsion Laboratory has recommended five feeders for testing. (LTN)
Date: January 1, 1978
Partner: UNT Libraries Government Documents Department

Physical and chemical characterization of synthetic calcined sludge

Description: Calcined synthetic sludge was chemically characterized in support of engineering studies to design a processing plant to solidify highly radioactive waste at the Savannah River Plant. An analytical technique is described which provides quantitative data by mass spectrometric analysis of gases evolved during thermogravimetric analysis without measurements of gas flow rates or mass spectrometer sensitivities. Scanning electron microprobe analysis, Mossbauer spectroscopy, and several other common analytical methods were also used. Calcined sludge consists primarily of amorphous particles of hydrous oxides with iron, manganese, nickel, and calcium distributed fairly uniformly throughout the powder. Iron, manganese, nickel, and calcium exist in forms that are highly insoluble in water, but aluminum, sulfate, nitrate, and sodium exhibit relative water solubilities that increase in the given order from 60% to 94%. Evolved gas analysis in a helium atmosphere showed that calcined sludge is completely dehydrated by heating to 400/sup 0/C, carbon dioxide is evolved between 100 to 700/sup 0/C with maximum evolution at 500/sup 0/C, and oxygen is evolved between 400 and 1000/sup 0/C. Evolved gas analyses are also reported for uncalcined sludge. A spinel-type oxide similar to NiFe/sub 2/O/sub 4/ was detected by x-ray diffraction analysis at very low-level in calcined sludge.
Date: March 1, 1982
Creator: Slates, R.V.; Mosley, W.C. Jr.; Tiffany, B. & Stone, J.A.
Partner: UNT Libraries Government Documents Department

A scoping study of fission product transport from failed fuel during N Reactor postulated accidents

Description: This report presents a scoping study of cesium, iodine, and tellurium behavior during a cold leg manifold break in the N Reactor. More detail about fission product behavior than has previously been available is provided and key parameters that control this behavior are identified. The LACE LA1 test and evidence from the Power Burst Facility Severe Fuel Damage tests are used to test the key model applied to determine aerosol behavior. Recommendations for future analysis are also provided. The primary result is that most of the cesium, iodine, and tellurium remains in the molten uranium fuel. Only 0.0035 of the total inventory is calculated to be released. Condensation of the most of the species of cesium and iodine that are released is calculated, with 0.998 of the released cesium and iodine condensing in the spacers and upstream end of the connector tubes. Most of the tellurium that is released condenses, but the chemical reaction of tellurium vapor with surfaces is also a major factor in the behavior of this element.
Date: January 1, 1988
Creator: Hagrman, D.L.
Partner: UNT Libraries Government Documents Department

Ion-assisted doping of 2-6 compounds during physical vapor deposition

Description: This report describes a research program to (1) investigate ion-assisted doping during chemical vapor deposition of CdTe and (2) determine the influence of co-depositing ionized dopant atoms in the growth and structural and photoelectronic properties of the deposited films. In p-CdTe homo-epitaxial films, we controlled doping up to about 6 {times} 10{sup 16} cm{sup {minus}3} and 2 {times} 10{sup 17} cm{sub {minus}3} or ion-assisted depositions with As and P ions, respectively. At a growth rate of approximately 0.1 {mu}m/min, a substrate temperature of 400{degree}C, and ion energy of 60 eV, a maximum doping density was found near an ion current of 0.6{mu}A/cm{sup 2}. Related studies included elucidating the role of low-energy ion damage in the ion-assisted doping process, and investigating the decrease in carrier density near the surface of p-CdTe upon heating in vacuum, H{sub 2}, or Ar. We demonstrate the ability to make carrier density profiles and to grade junctions, and we present preliminary results from polycrystalline p-CdTe films grown on graphite and alumina substrates. We also present solar cells prepared using the p-CdTe as the collector area and n-CdS as the window layer, and we examine their photovoltaic parameters for different carrier densities and configurations in p-CdTe. 91 refs., 44 figs., 5 tabs.
Date: July 1, 1990
Creator: Bube, R H
Partner: UNT Libraries Government Documents Department

Recent developments in the CONTAIN-LMR code

Description: Through an international collaborative effort, a special version of the CONTAIN code is being developed for integrated mechanistic analysis of the conditions in liquid metal reactor (LMR) containments during severe accidents. The capabilities of the most recent code version, CONTAIN LMR/1B-Mod.1, are discussed. These include new models for the treatment of two condensables, sodium condensation on aerosols, chemical reactions, hygroscopic aerosols, and concrete outgassing. This code version also incorporates all of the previously released LMR model enhancements. The results of an integral demonstration calculation of a sever core-melt accident scenario are given to illustrate the features of this code version. 11 refs., 7 figs., 1 tab.
Date: January 1, 1990
Creator: Murata, K.K.
Partner: UNT Libraries Government Documents Department

A fixed granular-bed sorber for measurement and control of alkali vapors in PFBC (pressurized fluidized-bed combustion)

Description: Alkali vapors (Na and K) in the hot flue gas from the pressurized fluidized-bed combustion (PFBC) of coal could cause corrosion problems with the gas turbine blades. In a laboratory-scale PFBC test with Beulah lignite, a fixed granular bed of activated bauxite sorbent was used to demonstrate its capability for measuring and controlling alkali vapors in the PFBC flue gas. The Beulah lignite was combusted in a bed of Tymochtee dolomite at bed temperatures ranging from 850 to 875{degrees}C and a system pressure of 9.2 atm absolute. The time-averaged concentration of sodium vapor in the PFBC flue gas was determined from the analysis of two identical beds of activated bauxite and found to be 1.42 and 1.50 ppmW. The potassium vapor concentration was determined to be 0.10 ppmW. The sodium material balance showed that only 0.24% of the total sodium in the lignite was released as vapor species in the PFBC flue gas. This results in an average of 1.56 ppmW alkali vapors in the PFBC flue gas. This average is more than 1.5 orders of magnitude greater than the currently suggested alkali specification limit of 0.024 ppm for an industrial gas turbine. The adsorption data obtained with the activated bauxite beds were also analyzed mathematically by use of a LUB (length of unused bed)/equilibrium section concept. Analytical results showed that the length of the bed, L{sub o} in centimeters, relates to the break through time, {theta}{sub b} in hours, for the alkali vapor to break through the bed as follows: L{sub o} = 33.02 + 1.99 {theta}{sub b}. This formula provides useful information for the engineering design of fixed-bed activated bauxite sorbers for the measurement and control of alkali vapors in PFBC flue gas. 26 refs., 4 figs., 4 tabs.
Date: January 1, 1990
Creator: Lee, S.H.D. & Swift, W.M.
Partner: UNT Libraries Government Documents Department

SPARC-90: A code for calculating fission product capture in suppression pools

Description: This report describes the technical bases and use of two updated versions of a computer code initially developed to serve as a tool for calculating aerosol particle retention in boiling water reactor (BWR) pressure suppression pools during severe accidents, SPARC-87 and SPARC-90. The most recent version is SPARC-90. The initial or prototype version (Owczarski, Postma, and Schreck 1985) was improved to include the following: rigorous treatment of local particle deposition velocities on the surface of oblate spherical bubbles, new correlations for hydrodynamic behavior of bubble swarms, models for aerosol particle growth, both mechanistic and empirical models for vent exit region scrubbing, specific models for hydrodynamics of bubble breakup at various vent types, and models for capture of vapor iodine species. A complete user's guide is provided for SPARC-90 (along with SPARC-87). A code description, code operating instructions, partial code listing, examples of the use of SPARC-90, and summaries of experimental data comparison studies also support the use of SPARC-90. 29 refs., 4 figs., 11 tabs.
Date: October 1, 1991
Creator: Owczarski, P.C. & Burk, K.W. (Pacific Northwest Lab., Richland, WA (United States))
Partner: UNT Libraries Government Documents Department

Investigation of mechanisms of ash deposit formation from low-rank coal combustion: Final report

Description: This project was undertaken to determine the chemical behavior of alkali metal and other species implicated in the ash fouling which can occur during the combustion of low rank coals. The coal combustion was studied in unaugmented premixed pulverized coal flames. Vapor species were measured by molecular beam mass spectrometry. Temperatures were also measured, and time-resolved coal/ash particulate samples were collected and analyzed. A major part of the research on this project was devoted to: (1) the development and refinement of techniques for the MBMS analysis of trace quantities of unstable and reactive high temperature vapor species from the pulverized coal flames; and (2) the time-resolved sampling and collection of particulates. The equipment is now operating very satisfactorily. Inorganic species, some of which were present at parts-per-million levels, were quantitatively sampled and measured in the pulverized coal flames. Time-resolved particulate samples which were free of vapor deposited contaminants were collected without the use of an interfering substrate. Profiles of the alkali metal species in Beulah lignite and Decker subbituminous coal flames were obtained. It was found in both flames that sodium is volatilized as the atomic species early (milliseconds) in the combustion process. The gaseous Na reacts, also in milliseconds, to form an unknown species which is probably an oxide fume, but which is not NaOH or Na/sub 2/SO/sub 4/. This is probably the mechanism for the formation of the alkali ''fumes'' observed in other systems. Measurements were also made of a number of other gaseous species, and time-resolved coal/ash samples were obtained and analyzed. 27 refs., 23 figs., 8 tabs.
Date: August 1, 1987
Creator: Greene, F. T. & O'Donnell, J. E.
Partner: UNT Libraries Government Documents Department

Investigation of the corrosion behavior of cooling coil material in a simulated concrete environment

Description: Pitting corrosion of the cooling coils embedded in the concrete roof of the waste tanks is one of the suspected causes of the recent cooling coil failures. Cyclic polarization tests were conducted to predict the threshold chloride level above which pitting would initiate. The threshold chloride level was determined to be 9000 ppM. Although these tests predict the electrochemical or corrosion behavior of the metal, they may not predict the severity of attack. Further tests which investigate the effect of the permeability of the concrete matrix on the transport of water and oxygen to the metal surface are planned to assess the severity of attack.
Date: February 1, 1993
Creator: Wiersma, B.J.
Partner: UNT Libraries Government Documents Department

Effects of a range of machined and ground surface finishes on the simulated reactor helium corrosion of several candidate structural materials. [Inconel MA 754]

Description: This report discusses the corrosion behavior of several candidate reactor structural alloys in a simulated advanced high-temperature gas-cooled reactor (HTGR) environment over a range of lathe-machined and centerless-ground surface finishes. The helium environment contained 50 Pa H/sub 2//5 Pa CO/5 Pa CH/sub 4//<0.05 Pa H/sub 2/O (500 ..mu..atm H/sub 2//50 ..mu..atm CO/50 ..mu..atm CH/sub 4//<0.5 ..mu..atm H/sub 2/O) at 900/sup 0/C for a total exposure of 3000 h. The test alloys included two vacuum-cast superalloys (IN 100 and IN 713LC); a centrifugally cast austenitic alloy (HK 40); three wrought high-temperature alloys (Alloy 800H, Hastelloy X, and Inconel 617); and a nickel-base oxide-dispersion-strengthened alloy (Inconel MA 754). Surface finish variations did not affect the simulated advanced-HTGR corrosion behavior of these materials. Under these conditions, the availability of reactant gaseous impurities controls the kinetics of the observed gas-metal interactions. Variations in the near-surface activities and mobilities of reactive solute elements, such as chromium, which might be expected to be affected by changes in surface finish, do not seem to greatly influence corrosion in this simulated advanced HTGR environment. 18 figures, 4 tables.
Date: February 1, 1981
Creator: Thompson, L.D.
Partner: UNT Libraries Government Documents Department

Regional aerosol deposition in human upper airways

Description: During the current report experimental studies of upper respiratory deposition of radon progeny aerosols and stimulant aerosols were carried out in replicate casts of nasal and oral passages of adults and children. Additionally, preliminary studies of nasal passage deposition of unattached Po{sup 218} particles was carried out in four human subjects. Data on nasal inspiratory deposition in replicate models of adults and infants from three collaborating laboratories were compared and a best-fit curve of deposition efficiency for both attached and unattached particles was obtained, showing excellent inter-laboratory agreement. This curve demonstrates that nasal inspiratory deposition of radon progeny is weakly dependent upon flow rate over physiologically realistic ranges of flow, does not show a significant age effect, and is relatively independent of nasal passage dimensions for a given age range. Improved replicate models of the human adult oral passage extending to the mid-trachea were constructed for medium and higher flow mouth breathing states; these models were used to assess the deposition of unattached Po{sup 218} particles during oronasal breathing in the oral passage and demonstrated lower deposition efficiency than the nasal passage. Measurements of both Po{sup 218} particle and attached fraction particle size deposition were performed in replicate nasal passage of a four week old infant. 5 refs., 1 fig.
Date: November 1, 1991
Creator: Swift, D.L.
Partner: UNT Libraries Government Documents Department

Coal technology program. Progress report, May 1977

Description: Two successful operability tests with sustained operation of the bench-scale hydrocarbonizer were achieved with Illinois No. 6 coal diluted with char. Several activities in the area of nondestructive testing of coatings are reviewed. Failure analysis activities included examination of several components from the solvent refined coal plants at Wilsonville, Alabama, and Tacoma, Washington. In the gas-fired potassium boiler project, all of the design work were completed except for several of the instrument and control drawings. In the design studies of a coal-fired alkali metal vapor topping cycle, the first phase of a cycle analysis and the design and analysis of a metal vapor turbine were completed. A report entitled &#x27;&#x27;Critical Component Test Facility--Advance Planning for Test Modules&#x27;&#x27; presents the planning study for the conceptual design of component test modules on a nonsite-specific basis. Engineering studies, project evaluation and process and program analysis of coal conversion processes were continued. A report on the landfill storage of solid wastes from coal conversion is being finalized. In the coal-fueled MIUS project, a series of successful tests of the coal feeding system and a report on the analysis of 500-hr fire-side corrosion tests in a fluidized bed combustor were completed.
Date: July 1, 1977
Partner: UNT Libraries Government Documents Department