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Tables of thermodynamic functions for analysis of aircraft-propulsion systems

Description: Report presenting tables of thermodynamic functions for 42 substances containing argon, aluminum, boron, carbon, chlorine, fluorine, hydrogen, lithium, nitrogen, and oxygen. The functions examined included the specific heat at constant pressure, sensible enthalpy, sum of sensible enthalpy and chemical energy, molar entropy, enthalpy change due to formation of substance from elements in atomic gas state divided by gas constant times temperature, and the logarithm of the equilibrium constant at designated temperatures.
Date: August 1950
Creator: Huff, Vearl N. & Gordon, Sanford
Partner: UNT Libraries Government Documents Department

Fundamental Study of Low NOx Combustion Fly Ash Utilization

Description: This study is principally concerned with characterizing the organic part of coal combustion fly ashes. High carbon fly ashes are becoming more common as by-products of low-NOx combustion technology, and there is need to learn more about this fraction of the fly ash. The project team consists of two universities, Brown and Princeton, and an electrical utility, New England Power. A sample suite of over forty fly ashes has been gathered from utilities across the United States, and includes ashes from a coals ranging in rank from bituminous to lignite. The characterizations of these ashes include standard tests (LOI, Foam Index), as well as more detailed characterizations of their surface areas, porosity, extractability and adsorption behavior. The ultimate goal is, by better characterizing the material, to enable broadening the range of applications for coal fly ash re-use beyond the current main market as a pozzolanic agent for concretes. The potential for high carbon-content fly ashes to substitute for activated carbons is receiving particular attention. The work performed to date has already revealed how very different the surfaces of different ashes produced by the same utility can be, with respect to polarity of the residual carbon. This can help explain the large variations in acceptability of these ashes as concrete additives.
Date: May 1, 1997
Creator: Suubert, E. M.; Kuloats, I.; Smith, K.; Sabanegh, N.; Hurt, R.H.; Lilly, W. D. et al.
Partner: UNT Libraries Government Documents Department

The role of pore structure on char reactivity. Quarterly progress report, October 1994--December 1994

Description: In order to examine the role of pore structure, studies will be conducted on coal chars in the electrodynamic balance. Larger particles will also be examined using a fluidized bed to examine diffusion control reactions, and soot will also be investigated to examine the role of meso- and micro-pores without macro-pore interference. These studies will allow a full range of particles sizes and temperatures to be investigated and eventually modeled.
Date: January 1, 1995
Creator: Sarofim, A. F.
Partner: UNT Libraries Government Documents Department

Influence of sample composition on aerosol organic and black carbon determinations

Description: In this paper we present results on characterization of filter-collected redwood (Sequoia sempevirens)-needle and eucalyptus smoke particles by thermal, optical, and solvent extraction methods. Our results demonstrate that organic and black carbon concentrations determined by thermal and optical methods are not only method dependent, but also critically influenced by the overall chemical composition of the samples. These conclusions are supported by the following: (1) the organic fraction of biomass smoke particles analyzed includes a component, ranging in concentration from about 6-20% of total carbon or from 16-30% of organic carbon, that is relatively non-volatile and has a combustion temperature close to that of black carbon; (2) presence of K or Na in biomass smoke samples lowers the combustion temperatures of this organic component and of black carbon, making their combustion properties indistinguishable; (3) about 20% of total organic material is nonvolatile when heated to 550{degrees}C in an inert atmosphere. Consequently, thermal methods that rely on a specific temperature to separate organic from black carbon may either underestimate or overestimate the black and organic carbon concentrations, depending on the amounts of Na and K and on the composition and concentration of organic material present in a sample. These analytical uncertainties and, under some conditions, absorption by organic material may contribute to the variability of empirically derived proportionality between light transmission through filter deposits and black carbon concentrations.
Date: July 1, 1995
Creator: Novakov, T. & Corrigan, C.E.
Partner: UNT Libraries Government Documents Department

Fundamental Study of Low-Nox Combustion Fly Ash Utilization

Description: This study is principally concerned with characterizing the organic part of coal combustion fly ashes. High carbon fly ashes are becoming more common as by-products of low-NOx combustion technology, and there is need to learn more about this fraction of the fly ash. The project team consists of two universities, Brown and Princeton, and an electrical utility, New England Power. A sample suite of over forty fly ashes has been gathered from utilities across the United States, and includes ashes from a coals ranging in rank from bituminous to lignite. The characterizations of these ashes include standard tests (LOI, Foam Index), as well as more detailed characterizations of their surface areas, porosity, extractability and adsorption behavior. The ultimate goal is, by better characterizing the material, to enable broadening the range of applications for coal fly ash re-use beyond the current main market as a pozzolanic agent for concretes. The potential for high carbon-content fly ashes to substitute for activated carbons is receiving particular attention. The work performed to date has already revealed how very different the surfaces of different ashes produced by the same utility can be, with respect to polarity of the residual carbon. This can help explain the large variations in acceptability of these ashes as concrete additives.
Date: November 1, 1997
Creator: Suuberg, E. M.; Kuloats, I.; Smith, K.; Sabanegh, N.; Hurt, R. H.; Lilly, W. D. et al.
Partner: UNT Libraries Government Documents Department

Residues From Coal Comversion and Utilization: Advanced Mineralogical Characterization and Disposed Byproduct Diagensesis

Description: The goals of the project are two-fold: 1) to upgrade semi-quantitative X-ray diffraction(QXRD) methods presently used in analyzing complex coal combustion by-product (CCB)systems, with the quantitative Rietveld method, and 2) to apply this method to a set of by-product materials that have been disposed or utilized for a long period (5 years or more) in contact with the natural environment, to further study the nature of CCB diagenesis. The project is organized into three tasks to accomplish these two goals: 1) thorough characterization of a set of previously analyzed disposed by-product materials, 2) development of a set of CCB specific protocols for Rietveld QXRD, and 3) characterization of an additional set of disposed CCB materials, including application of the protocols for Rietveld QXRD developed in Task 2.
Date: December 4, 1998
Creator: McCarthy, Gregory J.
Partner: UNT Libraries Government Documents Department

Zinc Bromide Combustion: Implications for the Consolidated Incinerator Facility

Description: In the nuclear industry, zinc bromide (ZnBr2) is used for radiation shielding. At Savannah River Site (SRS) zinc bromide solution, in appropriate configurations and housings, was used mainly for shielding in viewing windows in nuclear reactor and separation areas. Waste stream feeds that will be incinerated at the CIF will occasionally include zinc bromide solution/gel matrices.The CIF air pollution systems control uses a water-quench and steam atomizer scrubber that collects salts, ash and trace metals in the liquid phase. Water is re-circulated in the quench unit until a predetermined amount of suspended solids or dissolved salts are present. After reaching the threshold limit, "dirty liquid", also called "blowdown", is pumped to a storage tank in preparation for treatment and disposal. The air pollution control system is coupled to a HEPA pre-filter/filter unit, which removes particulate matter from the flue gas stream (1).The objective of this report is to review existing literature data on the stability of zinc bromide (ZnBr2) at CIF operating temperatures (>870 degrees C (1600 degrees F) and determine what the combustion products are in the presence of excess air. The partitioning of the combustion products among the quencher/scrubber solution, bottom ash and stack will also be evaluated. In this report, side reactions between zinc bromide and its combustion products with fuel oil were not taken into consideration.
Date: December 16, 1998
Creator: Oji, L.N.
Partner: UNT Libraries Government Documents Department

Equation of state for detonation products

Description: To be useful, an equation of state for detonation products must allow rapid computation. The constraints applied by this requirement have surprising thermodynamic effects. Some of these are discussed here. A simple, complete equation of state is proposed, and its properties are discussed. With the form assumed here, all the useful integrals (except for the Riemann integral) can be written simply and explicitly, so the behavior of the important variables can be easily seen. The complete equation of state is calibrated for PBX9404 and PBX9501.
Date: December 31, 1998
Creator: Davis, W.C.
Partner: UNT Libraries Government Documents Department

Cycle-by-cycle combustion variations in spark-ignited engines

Description: Under constant nominal operating conditions, internal combustion engines can exhibit substantial variation in combustion efficiency from one cycle to the next. Previous researchers have attempted to explain these variations as resulting from stochastic, linear, or chaotic physical processes. Our investigations indicate that cyclic combustion variations can be explained as the result of interactions between a global low-dimensional nonlinearity and small-scale, high-dimensional processes that perturb the nonlinearity. Using this approach, we have proposed a simple model that accurately simulates experimentally observed patterns in cyclic combustion variations. Our model also explains the apparent discrepancies among previous investigators regarding the basic nature of cyclic variations. Further, it appears that symbol dynamics are useful for characterizing the observed model and experimental behavior.
Date: September 1, 1997
Creator: Daw, C.S.; Finney, C.E.A. & Connolly, F.T.
Partner: UNT Libraries Government Documents Department

Phenyl radical thermolysis and rate constants for phenyl + O{sub 2}

Description: The thermal decomposition of C{sub 6}H{sub 5}I has been used to prepare in-situ known initial concentrations of phenyl radicals at high temperatures. These can be degraded by direct decomposition at T > 1350 K giving H + C{sub 6}H{sub 4}. Using H-atom ARAS, rate constants for C{sub 6}H{sub 5} dissociation have been measured. Using the same ARAS technique, constants for C{sub 6}H{sub 5} dissociation have been measured. Using the same ARAS technique, the H- and O-atoms formed from the reaction, C{sub 6}H{sub 5} + O{sub 2}, have both been measured. The rate constant results are discussed along with lower T measurements in terms of RRKM calculations using published ab initio electronic structure determinations of transition states.
Date: August 1, 1997
Creator: Kumaran, S.S. & Michael, J.V.
Partner: UNT Libraries Government Documents Department

Residues From Coal Conversion and Utilization: Advanced Mineralogical Characterization and Disposed Byproduct Diagenesis

Description: The goals of the project are two-fold: 1) to upgrade semi-quantitative X-ray diffraction(QXRD) methods presently used in analyzing complex coal combustion by-product (CCB)systems, with the quantitative Rietveld method, and 2) to apply this method to a set of by-product materials that have been disposed or utilized for a long period (5 years or more) in contact with the natural environment, to further study the nature of CCB diagenesis. The project is organized into three tasks to accomplish these two goals: 1) thorough characterization of a set of previously analyzed disposed by-product materials, 2) development of a set of CCB specific protocols for Rietveld QXRD, and 3) characterization of an additional set of disposed CCB materials, including application of the protocols for Rietveld QXRD developed in Task 2.
Date: December 4, 1998
Creator: McCarthy, Gregory J.
Partner: UNT Libraries Government Documents Department

SILICON CARBIDE MICRO-DEVICES FOR COMBUSTION GAS SENSING UNDER HARSH CONDITIONS

Description: A sensor based on the wide bandgap semiconductor, silicon carbide (SiC), has been developed for the detection of combustion products in power plant environments. The sensor is a catalytic gate field effect device that can detect hydrogen containing species in chemically reactive, high temperature environments. Robust metallization and electrical contacting techniques have been developed for device operation at elevated temperatures. To characterize the time response of the sensor responses in the millisecond range, a conceptually new apparatus has been built. Software has been developed to cope with the requirements of fast sensor control and data recording. In addition user friendly software has been developed to facilitate use of the SiC sensors for industrial process control applications.
Date: April 1, 2004
Creator: Ghosh, Ruby N.; Tobias, Peter & Tobin, Roger G.
Partner: UNT Libraries Government Documents Department

SENSITIZATION AND EXACERBATION OF ALLERGIC DISEASES BY DIESEL ENGINE PARTICLES

Description: Most studies of the health effects of diesel exhaust have focused on the controversial issue of its role in cancer. However, recently the role of combustion products such as diesel exhaust particles (DEP) in modulating the immune response has garnered much attention. In particular the effect of DEP on allergic and asthmatic diseases has been the focus of many studies. A link between industrialization and allergic disease has long been presumed. Indeed, only 50 years after the first recorded reported case of allergy in 1819, Charles Blackely wrote that the ''hay-fever epidemic'' was associated with the movement of people from the country into the cities. Ishizaki et al. (1987) found that people in Japan living on busy roads lined with cedar trees have more allergies to cedar than residents living on similar streets with much less traffic. Since that time other epidemiological studies have reported similar findings. Kramer, et al., showed that hay fever is greater in residential areas with heavy truck traffic, while Weiland, et al., reported that allergic symptoms correlate with the distance of residences to roads with heavy traffic.
Date: August 20, 2000
Creator: Diaz-Sanchez, David
Partner: UNT Libraries Government Documents Department

Nitrogen release during coal combustion

Description: Experiments in entrained flow reactors at combustion temperatures are performed to resolve the rank dependence of nitrogen release on an elemental basis for a suite of 15 U.S. coals ranging from lignite to low-volatile bituminous. Data were obtained as a function of particle conversion, with overall mass loss up to 99% on a dry, ash-free basis. Nitrogen release rates are presented relative to both carbon loss and overall mass loss. During devolatilization, fractional nitrogen release from low-rank coals is much slower than fractional mass release and noticeably slower than fractional carbon release. As coal rank increases, fractional nitrogen release rate relative to that of carbon and mass increases, with fractional nitrogen release rates exceeding fractional mass and fractional carbon release rates during devolatilization for high-rank (low-volatile bituminous) coals. At the onset of combustion, nitrogen release rates increase significantly. For all coals investigated, cumulative fractional nitrogen loss rates relative to those of mass and carbon passes through a maximum during the earliest stages of oxidation. The mechanism for generating this maximum is postulated to involve nascent thermal rupture of nitrogen-containing compounds and possible preferential oxidation of nitrogen sites. During later stages of oxidation, the cumulative fractional loss of nitrogen approaches that of carbon for all coals. Changes in the relative release rates of nitrogen compared to those of both overall mass and carbon during all stages of combustion are attributed to a combination of the chemical structure of coals, temperature histories during combustion, and char chemistry.
Date: February 1, 1995
Creator: Baxter, L. L.; Mitchell, R. E.; Fletcher, T. H. & Hurt, R. H.
Partner: UNT Libraries Government Documents Department

Coal Combustion Products Extension Program

Description: This final project report presents the activities and accomplishments of the ''Coal Combustion Products Extension Program'' conducted at The Ohio State University from August 1, 2000 to June 30, 2005 to advance the beneficial uses of coal combustion products (CCPs) in highway and construction, mine reclamation, agricultural, and manufacturing sectors. The objective of this technology transfer/research program at The Ohio State University was to promote the increased use of Ohio CCPs (fly ash, FGD material, bottom ash, and boiler slag) in applications that are technically sound, environmentally benign, and commercially competitive. The project objective was accomplished by housing the CCP Extension Program within The Ohio State University College of Engineering with support from the university Extension Service and The Ohio State University Research Foundation. Dr. Tarunjit S. Butalia, an internationally reputed CCP expert and registered professional engineer, was the program coordinator. The program coordinator acted as liaison among CCP stakeholders in the state, produced information sheets, provided expertise in the field to those who desired it, sponsored and co-sponsored seminars, meetings, and speaking at these events, and generally worked to promote knowledge about the productive and proper application of CCPs as useful raw materials. The major accomplishments of the program were: (1) Increase in FGD material utilization rate from 8% in 1997 to more than 20% in 2005, and an increase in overall CCP utilization rate of 21% in 1997 to just under 30% in 2005 for the State of Ohio. (2) Recognition as a ''voice of trust'' among Ohio and national CCP stakeholders (particularly regulatory agencies). (3) Establishment of a national and international reputation, especially for the use of FGD materials and fly ash in construction applications. It is recommended that to increase Ohio's CCP utilization rate from 30% in 2005 to 40% by 2010, the CCP Extension Program ...
Date: January 11, 2006
Creator: Butalia, Tarunjit S. & Wolfe, William E.
Partner: UNT Libraries Government Documents Department

JV 58-Effects of Biomass Combustion on SCR Catalyst

Description: A portable slipstream selective catalytic reduction (SCR) reactor was installed at a biomass cofired utility boiler to examine the rates and mechanisms of catalyst deactivation when exposed to biomass combustion products. The catalyst was found to deactivate at a much faster rate than typically found in a coal-fired boiler, although this may have been the result of high ash loading rather than a general property of biomass combustion. Deactivation was mainly the result of alkali and alkaline-earth sulfate formation and growth in catalyst pores, apparently caused by alkaline-earth ash deposition on or near the pore sites. The high proportion of biomass in the fuel contributed to elevated levels of alkali and alkaline-earth material in the ash when compared to coal ash, and these higher levels provided more opportunity for sulfate formation. Based on laboratory tests, neither catalyst material nor ammonia contributed measurably to ash mass gains via sulfation. A model constructed using both field and laboratory data was able to predict catalyst deactivation of catalysts under subbituminous coal firing but performed poorly at predicting catalyst deactivation under cofiring conditions. Because of the typically higher-than coal levels of alkali and alkaline-earth elements present in biomass fuels that are available for sulfation at typical SCR temperatures, the use of SCR technology and biomass cofiring needs to be carefully evaluated prior to implementation.
Date: August 31, 2006
Creator: Folkedahl, Bruce C.; Zygarlicke, Christopher J.; Strege, Joshua R.; McCollor, Donald P.; Laumb, Jason D. & Kong, Lingbu
Partner: UNT Libraries Government Documents Department

Chemical Fixation of CO2 in Coal Combustion Products and Recycling through Biosystems

Description: This Annual Technical Progress Report presents the principal results in enhanced growth of algae using coal combustion products as a catalyst to increase bicarbonate levels in solution. Optimal production of biomass depends on a number of factors. These factors include pH management, harvesting, and impact of auxiliary operations on the algae population. A number of experiments are presented which attempt to identify and characterize the impact of these factors.
Date: September 30, 2002
Creator: Copeland, C. Henry; Pier, Paul; Whitehead, Samantha & Behel, David
Partner: UNT Libraries Government Documents Department

Chemical Fixation of CO2 in Coal Combustion Products and Recycling through Biosystems

Description: This Annual Technical Progress Report presents the principle results in enhanced growth of algae using coal combustion products as a catalyst to increase bicarbonate levels in solution. A co-current reactor is present that increases the gas phase to bicarbonate transfer rate by a factor of five to nine. The bicarbonate concentration at a given pH is approximately double that obtained using a control column of similar construction. Algae growth experiments were performed under laboratory conditions to obtain baseline production rates and to perfect experimental methods. The final product of this initial phase in algae production is presented.
Date: September 30, 2001
Creator: Copeland, C. Henry; Pier, Paul; Whitehead, Samantha & Behel, David
Partner: UNT Libraries Government Documents Department

Speciation and Attenuation of Arsenic and Selenium at Coal Combustion By-Product Management Facilities

Description: The overall objective of this project was to evaluate the impact of key constituents captured from power plant air streams (principally arsenic and selenium) on the disposal and utilization of coal combustion products (CCPs). Specific objectives of the project were: (1) to develop a comprehensive database of field leachate concentrations at a wide range of CCP management sites, including speciation of arsenic and selenium, and low-detection limit analyses for mercury; (2) to perform detailed evaluations of the release and attenuation of arsenic species at three CCP sites; and (3) to perform detailed evaluations of the release and attenuation of selenium species at three CCP sites. Each of these objectives was accomplished using a combination of field sampling and laboratory analysis and experimentation. All of the methods used and results obtained are contained in this report. For ease of use, the report is subdivided into three parts. Volume 1 contains methods and results for the field leachate characterization. Volume 2 contains methods and results for arsenic adsorption. Volume 3 contains methods and results for selenium adsorption.
Date: December 31, 2005
Creator: Ladwig, K.
Partner: UNT Libraries Government Documents Department

Methylmercury risk assessment issues

Description: This paper reviews the general background of health risks associated with mercury (Hg), primarily methylmercury (MeHg), with a view towards application to advanced technologies that could reduce any contributions from coal combustion. The need for accurate assessment of such risks is discussed, since Hg is now widely dispersed in the environment and cannot easily be eliminated. The primary pathway of MeHg intake is through eating contaminated fish. The issues of concern include identification of critical health outcomes (various neurological indices) and their confounding factors, accurate assessment of MeHg intake rates, and appropriate use of dose-response functions. Ultimately, such information will be used to evaluate alternative coal combustion systems.
Date: July 1, 1996
Creator: Lipfert, F.W. & Saroff, L.
Partner: UNT Libraries Government Documents Department

Quantifying magnitudes and distributions of CO sources

Description: We use a simplified version of the GRANTOUR chemical tracer model to analyze emissions of CO from various sources. The GRANTOUR model has been simplified to include the eigenvalue chemistry solution method of Prather (1994). The analysis includes fossil fuel combustion, biomass burning, hydrocarbon oxidation, ocean, and terrestrial sources of CO. We also present a 1{degree} x 1{degree} emissions inventory of CO from fossil fuel combustion.
Date: March 1, 1998
Creator: Dignon, J.; Penner, J. E. & Walton, J. J.
Partner: UNT Libraries Government Documents Department

Flamelet/flow interaction in premixed turbulent flames: simultaneous measurements of gas velocity and flamelet position

Description: An experimental technique for obtaining simultaneous measurements of fluid velocity and flamelet position in premixed flames is described and applied in a turbulent V-flame. The flamelet position information is used to calculate conditional velocity statistics, conditional on both zone (reactants or products) as well as conditional on distance from the flamelet. The conditional zone statistics demonstrate that increases (or decreases) in turbulence across the flame are dependent on axial position and location within the flame brush. The product- zone conditional covariance, coupled with the measured conditional mean velocity profiles, indicate that turbulence generation by shear may be a significant contribution to product zone turbulence levels. Velocity statistics conditional on distance from the flamelet demonstrate a considerable interaction between the flamelet and velocity field. Man and rms velocities vary significantly with proximity to the flamelet, such that differences in velocities which which occur just across the flamelet surface. The change in rms velocities just across the flamelet is found to be anisotropic, with the largest increase (smallest decrease) occurring in the axial velocity component. Rms velocities conditional on flamelet position further support the hypothesis that increased product gas velocity fluctuations may have a significant component associated with turbulence generation by mean shear.
Date: December 1, 1996
Creator: Miles, P.C. & Gouldin, F.C.
Partner: UNT Libraries Government Documents Department

Toxic substances from coal combustion -- a comprehensive assessment. Quarterly technical progress report, 1 April 1996--30 June 1996

Description: Before electric utilities can plan or implement emissions minimization strategies for hazardous pollutants, they must have an accurate and site-specific means of predicting emissions in all effluent streams for the broad range of fuels and operating conditions commonly utilized. Development of a broadly applicable emissions model useful to utility planners first requires a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion (specifically in Phase I, As, Se, Cr, and possibly Hg). PSI Technologies (PSIT) and its team members will achieve this objective through the development of an {open_quotes}Engineering Model{close_quotes} that accurately predicts the formation and partitioning of toxic species as a result of coal combustion. The {open_quotes}Toxics Partitioning Engineering Model{close_quotes} (ToPEM) will be applicable to all conditions including new fuels or blends, low-NO{sub x} combustion systems, and new power systems being advanced by DOE in the Combustion 2000 program. This report describes the mineralogy and chemical analysis of bituminous coal samples.
Date: July 1, 1996
Creator: Bool, L.E. III; Senior, C.L.; Huggins, F.; Huffman, G.P. & Shah, N.
Partner: UNT Libraries Government Documents Department