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1 Pershing, David W.; Wendt, Jost O. L.Pulverized coal combustion: the influence of flame temperature and coal composition on thermal and fuel NOxA laboratory combustor was used to investigate the factors that influence the conversion of fuel nitrogen in coal during coal combustion. Fuel NO was isolated by experimentation utilizing Argon / Oxygen / Carbon Dioxide mixtures as the oxidant, and care was taken to compare cases with air at matche...Fuel nitrogen; Flame temperature; Coal composition1977
2 Pershing, David W.; Wendt, Jost O. L.Investigation of first- and second-stage variables on control of NOx emissions using staged combustion in a pulverized coal wall-fired furnaceRecent tests on an EPA 1- to 1.5 x 106 Btu/hr pilot-scale pulverized coal furnace show that N0X emissions of 100 ppm to 150 ppm (zero percent 02) are achievable with the use of two-stage combustion. Comparable N0X emission levels were obtained with three different coal types fired in either the sing...NOx; Carbon monoxide; Emissions1979
3 Pershing, David W.Influence of fuel composition and flame temperature on the formation of thermal and fuel NOx in residual oil flamesA 900 kw model package boiler and a 20 kw laboratory tunnel furnace were used to study fuel and thermal NO, formation during heavy oil combustion. Package boiler results indicated that atomizer design, spray/ flow field interactions, and fuel composition were significant, dependent parameters. These...Residual oil flames1979
4 Pershing, David W.; Wendt, Jost O. L.Pulverized coal combustion: NOx formation mechanisms under fuel rich and staged combustion conditionsA 2 Kg/h pulverized fuel one dimensional flame combustor was used to determine time resolved NO profiles under fuel rich and staged combustion conditions. Seven solid fuels, including two coal chars, were investigated. Results show that at all fuel rich conditions NO is formed rapidly and then is ...Flame; Composition; Reaction1979
5 Pershing, David W.Control of NOx emissionsNITROGEN OXIDES (NOX) are produced in combustion from molecular nitrogen (thermal NOx) or from oxidation of nitrogen contained in the fuel (fuel NOx). Production of NOx in a turbulent diffusion flame is largely dependent upon fuel composition and fuel/air contacting, which for liquid fuels is determ...Staged heat release; Tunnel furnace; Boiler simulator; Staged combustion1980
6 Pershing, David W.Mechanisms of NOx formation and control: alternative and petroleum-derived liquid fuelsPetroleum-, coal- and shale-derived liquid fuels were burned in a downfired tunnel furnace to assess the impact of fuel properties on the formation and control of NOx emissions. A nitrogen-free oxidant mixture (Ar, C02 , 02) was used to isolate fuel NOx formation. Under excess air conditions fuel N...Exhaust emissions; Alternative fuels; Petroleum-derived liquid fuels1981
7 Pershing, David W.Influence of coal composition on the fate of volatile and char nitrogen during combustionFifty coals from North America, Europe, Asia, South Africa and Australia were burned in a 21 kW, refractory-lined tunnel furnace to determine the influence of coal properties on the fate of volatile and char nitrogen. Excess air fuel NO emissions (as determined by combustion in Ar/02/C02) ranged fro...Coal composition; Char nitrogen; Volatile nitrogen; NO emissions1982
8 Pershing, David W.; Slaughter, David MichaelParameters influencing the evolution and oxidation of sulfur in suspension phase coal combustionStoker coal-fired boiler furnaces are significant in terms of coal consumption and environmental impact; however, they have received relatively little research attention. This paper describes the results of a two-year study on the formation of sulfur oxides in the suspension phase of a coal-fired s...Stoker coal-fired furnaces1983
9 Pershing, David W.Formation and control of NO emissions from coal-fired spreader-stoker boilersStoker coal-fired furnaces are significant in terms of coal consumption and environmental impact; however, they have received little research attention. This paper describes the results of a study on the formation and control of nitrogen oxides in coal-fired spreader-stoker systems. Three scales of...Stoker coal-fired furnaces1983
10 Pershing, David W.Bench and pilot scale process evaluation of reburning for in-furnace NOx reductionThis paper describes a combined experimental and theoretical study which was undertaken to quantify the impact of fuel and process parameters on reburning effectiveness and provide the scaling information required for commercial application of reburning under highly varied industrial conditions. Ini...Reburning; Nitrogen oxides reduction; Staged fuel injection1986
11 Pershing, David W.Control of NOx and particulate emissions from spreader-stokers fired with hogged woodThe formation and emission of nitrogen oxides and particulate carry-over were studied from spreader-stoker combustion of hogged Douglas-fir, with a focus on optimizing the combustion conditions in each of the two distinct combustion zones, the bed phase and the suspension phase local oxygen availabi...Chemical analysis; Combustion; Emission; Engineering; Environmental control; Fuels; Nitrogen compounds; Particulates; NOx; Hogged wood1987
12 Pershing, David W.Biomass combustion: relationship between pollutant formation and fuel compositionA 65-kW refractory-walled reactor was used to study biomass combustion under conditions typical of the suspension-burning phase in a spreader-stoker-fired boiler. Isothermal combustion data and nitric oxide (NO) emission rates were obtained as a function of temperature, local oxygen concentration, ...Combustion; Emissions; Energy; Environmental control; Fuels; Pyrolysis; Biomass fuel; Particulates1989
13 Pershing, David W.Design and construction of a rotary kiln simulator for use in studying the incineration of hazardous wasteRotary kilns have been used extensively in the cement industry to calcine limestone. In the past few years, the technology has been viewed as a possible option for the incineration of hazardous waste materials, especially for the disposal of solid wastes and the cleanup of contaminated soils and tra...Rotary kilns; Hazardous waste; Waste burning1989-08
14 Veranth, John M.; Pershing, David W.; Sarofim, Adel F.Sources of unburned carbon in the fly ash produced from low-NOx pulverized coal combustionThe unburned carbon in the fly ash produced from low-NOx pulverized coal combustion is shown to consist of a mixture of soot and coal char. The soot was identified by the presence of chains or aggregates of 10-50-nm-diameter primary particles in electron microscope images of both laboratory sample...Unburned carbon; Char1998
15 Stringfellow, Gerald B.; Shurtleff, James KevinHeterostructures in GaInP grown using a change in Te dopingIn organometallic vapor phase epitaxy, changes in growth conditions can be used to modulate the extent of CuPt ordering and, hence, the band gap energy of GaInP. One method is to add Te during growth. An increase in the band gap energy of 0.1 eV due to a decrease in ordering has been obtained by ...Heterostructures; Alloys2000
16 Smith, Philip J.State space sensitivity to a prescribed probability density function shape in coal combustion systems: joint β-PDF versus clipped Gaussian PDFThe turbulent transport of three coal off-gas mixture fractions is coupled to a prescribed joint //-probability- density-function (//-PDF) mixing model. This physical transport and subgrid joint //-PDF mixing model is used to explore the incorporation of coal off-gas compositional disparities betwe...Off-gas stream; β-PDF; Char oxidation2000
17 Eddings, Eric G.; Sarofim, Adel F.; Pershing, David W.Production of nitrogen oxide during char oxidation at pulverized coal combustion conditionsMore stringent regulations for NOx control in pulverized coal combustors have made the scientific community focus on sources of emissions that were traditionally considered less relevant to the overall NOx production. The oxidation to NO of the nitrogen that is organically bound to the char is one o...2001
18 Lighty, Joann; Sarofim, Adel F.Carbon dioxide effects on metal vaporization during coal combustionCoal combustion products may take one of two forms. Residual ash (> 1 micron) is formed by particle shrinkage and breaking during combustion. Some material will vaporize and later recondense. During recondensation, these molecules have a high affinity for submicron particles because of the large sur...Coal combustion products; Metal vaporization; Carbon dioxide; Residual ash2001
19 Sarofim, Adel F.; Pugmire, Ronald J.13C NMR analysis of soot produced from model compounds and a coalSoot samples, including the associated organics, produced from an Illinois No. 6 coal (five samples) and two model compounds, biphenyl (three samples) and pyrene (two samples), have been studied by 13C NMR methods. The coal soot data served as a guide to selection of the temperature range that would...13C NMR; Biphenyl; Aromatic cluster size2001
20 Eddings, Eric G.; Sarofim, Adel F.Fast cook-off tests reportThe Center for the Simulation of Accidental Fires and Explosions (C-SAFE) at the University of Utah is focused on providing science-based tools for the numerical simulation of accident scenarios involving fires and high-energy devices (Pershing, 2000). The initial computational efforts are concentra...Heat flux; Heat transfer; Cookoff tests; Center for the Simulation of Accidental Fires and Explosions; C-SAFE2003
21 Sarofim, Adel F.Numerical combustion of aviation fuel part I: a cross-model comparison of n-heptane premixed flameFour different n-heptane mechanisms were used to simulate a fuel rich n-heptane premixed flame and their results were compared with experimental measurements. In addition to discussion of the numerical performance of each mechanism, flux analysis coupled with the atomic distribution technique was us...Aviation fuel; n-heptane; Premixed flame2003
22 Sarofim, Adel F.Simulation of soot formation using particle dynamics with one dimensional nucleation modeTwo soot formation models using particle dynamics with one-dimensional nucleation mode directly coupled with gas phase chemistry are tested on three ethylene and three methane laminar premixed flames. These models demonstrate strength in the prediction of concentration profiles of major combustion p...Soot formation models; Particle dynamics; One dimensional nucleation mode; Combustion chemistry2004
23 Eddings, Eric G.; Sarofim, Adel F.Thermal behavior of a high-energy material immersed in a fireOne of the uncertainties in the calculations of time-to-explosion for containers of high-energy materials immersed in fires is that of the thermal boundary at the container-explosive interface. Understanding this interface is critical in evaluating risks, safety issues and prevention mechanisms. In ...2004
24 Lighty, Joann; Sarofim, Adel F.; Eddings, Eric G.Modeling the coagulation of charged particlesOne important mechanism in the growth of soot particles is to understand the role of particle charge in the coagulation of the particles. A previously developed model has been extended to include the coagulation of charged particles. The model includes neutral particles and charged particles (up to ...Charged particles; Flame ionization; Modeling2004
25 Eddings, Eric G.NOx emissions from intermediate-temperature combustion of steel-industry by-product gasesA study of NOx emissions from the combustion of coke-oven gas and blast-furnace gas (steel industry by-product gases) was undertaken using detailed kinetic modeling to elucidate the pathways for NOx formation. The study was performed at the intermediate temperatures (1200-1400K) and 1 atm, which rep...2004
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