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Task 1.13 - Data Collection and Database Development for Clean Coal Technology By-Product Characteristics and Management Practices

Description: U.S. Department of Energy Federal Energy Technology Center-Morgantown (DOE FETC) efforts in the areas of fossil fuels and clean coal technology (CCT) have included involvement with both conventional and advanced process coal conversion by-products. In 1993, DOE submitted a Report to Congress on "Barriers to the Increased Utilization of Coal Combustion Desulfurization Byproducts by Governmental and Commercial Sectors" that provided an outline of activities to remove the barriers identified in the report. DOE charged itself with participation in this process, and the work proposed in this document facilitates DOE's response to its own recommendations for action. The work reflects DOE's commitment to the coal combustion by-product (CCB) industry, to the advancement of clean coal technology, and to cooperation with other government agencies. Information from DOE projects and commercial endeavors in fluidized-bed combustion (FBC) and coal gasification is the focus of this task. The primary goal is to provide an easily accessible compilation of characterization information on the by-products from these processes to government agencies and industry to facilitate sound regulatory and management decisions. Additional written documentation will facilitate the preparation of an updated final version of background information collected for DOE in preparation of the Report to Congress on barriers to CCB utilization.
Date: February 1, 1998
Creator: Pflughoeft-Hassett, Debra F.
Partner: UNT Libraries Government Documents Department

Task 1.15 - Enhanced Bioremediation of Coal Tar-Contaminated Soil

Description: The remediation of sites where soils have been contaminated with hydrophobic organic compounds is a major problem. This is especially true for manufactured gas plants (MGP) and similar industries. Gasification of fossil fuels has resulted in the production of tars that contain polyaromatic hydrocarbons (PAHs). PAHs are of concern because they are persistent in the environment and because many of them are carcinogenic. When soils contain very high concentrations of PAHs and other tar components, it is generally most feasible to use a chemical-physical remediation technique such as incineration. However, when the contaminant concentrations are medium to low, the most inexpensive technology is generally biological treatment. Biological treatment is an environmentally acceptable method of remediation that is relatively low-cost for many organic contaminants. PAHs and similar hydrophobic compounds, however, present major challenges to the microbial methods. These problems can be broken down into two related areas: mass transfer and bioavailability. The water volubility of most PAW is very small, and they have very low vapor pressures. As a result the diffkion of the sorbed PAHs to a location where a biodegrading microorganism can encounter it is often limiting. Complicating this is that especially in aged samples, the PAHs are bound so strongly to soil components, they are not available for the microorganisms. These two phenomena can be better understood by examination of a typical biodegradation curve, such as might be observed for mixed PAHs. In Figure 1, there are three phases of the biodegradation process plotted with respect to time. In the first phase, concentrations are changing only slowly as the microbes adapt to the conditions, grow to a larger population, and begin to biodegrade the PAHs. The second phase is the phase of rapid, often logarithmic, biodegradation. The third and last phase is that period when available concentrations of ...
Date: February 1, 1998
Creator: Gallagher, John R.
Partner: UNT Libraries Government Documents Department

Task 1.16 - Enhanced Mobility of Dense Nonaqueoius-Phase Liquids (DNAPLs) Using Dissolved Humic Acids

Description: Chlorinated solvent contamination is widespread across the U.S. Department of Energy (DOE) complex and other industrial facilities. Because of the physical properties of dense nonaqueous-phase liquids (DNAPLs), current treatment technologies are generally incapable of completely removing contamination from the source area. Incomplete removal means that the residual DNAPL will persist as a long-term source of groundwater contamination. When DNALPs occur in the subsurface, they resist remediation, owing to low water volubility, high viscosity and interracial tension, and microbial recalcitrance. Because of their high density and polarity, they are usually found sorbed to aquifer solids or in pools on impermeable materials. Surfactants have been used with some success to reduce interracial tension between the aqueous and organic phases and improve volubility of DNAPLs. However, surfactants are expensive and toxic and exhibit an oxygen demand. An alternative is the use of dissolved humic acids in improving DNAPL mobilization and solubilization. Humic acids, a. natural form of organic carbon, are abundant, inexpensive, and nontoxic; biodegrade slowly (low oxygen demand); and have excellent mobilization properties. The present work is to establish the feasibility of using humates for enhancing DNAPL remediation.
Date: August 1, 1997
Creator: Kurz, Marc D.
Partner: UNT Libraries Government Documents Department

Task 2.0 - Air Quality Assessment, Control, and Analytical Methods Subtask 2.11 - Lactic Acid FGD Additives From Sugar Beet Wastewater

Description: Organic buffers maintain the pH of the scrubber slurry in flue gas desulfurization (FGD) as the SO2 dissolves at the air-liquid interface. Inexpensive acids with an appropriate pKa are required for this application. The pKa of lactic acid (3.86) is between that of the interface and the recirculating slurry and will make soluble calcium ion available in large amounts. Currently lactic acid is somewhat expensive for this use, but this project will develop a new source of inexpensive lactate. Microbial action during the storage and processing of sugar beets forms lactic acid in concentrations as high 14 g/L in the processing water. The concentrations are lower than those occurring in conventional fermentation production of lactic acids, but since a considerable amount of water is involved in the processing of sugar beets in the Red River Valley (1 million gallons/day), a substantial amount of lactic acid or calcium lactate could be recovered as a by- product for use in FGD and other applications.
Date: February 1, 1998
Creator: Olson, Edwin S.
Partner: UNT Libraries Government Documents Department

Task 2.3 - Review and Assessment of Results From the Comprehensive Characterization of Toxic Emissions From Coal-Fired Power Plants

Description: To help meet the requirements of the 1990 Clean Air Act Amendments, the U.S. Department of Energy (DOE) sponsored Phase I of a study entitled "Comprehensive Characterization of Toxic - Emissions from Coal-Fired Power Plants" in 1992. Final reports which detail air toxic emissions from eight power plants (nine conilgurations) were completed by the contractors. The Energy & Environmental Research Center (EERC) served as an independent third-party reviewer of these reports; it has completed the activities as outlined for the initial review process and has prepared two reports. The fiist report, entitled "A Comprehensive Assessment of Toxic Emissions from Coal-Fired Power Plants: Phase I Results from the U.S. Department of Energy Study" was published in September 1996 and is available to the public and private sectors through the U. S. Department of Energy (DOE) Federal Energy Technology Center (FETC) at Pittsburgh. This report surnmar izes and evaluates the stack emission data. The second report prepared by the EERC, entitled "A Comprehensive Assessment of Toxic Emission from Coal-Fired Power Plants: Statistical Correlations from the Combined DOE and EPRI Field Test Data," details empirical correlations derived horn the Phase I DOE data and the Electric Power Research Institute (EPIU) PISCES (Power Plant Integrated Systems: Chemical Emissions Studies) data. The objective of the project was to provide an independent review of the Phase I data, evaluate the scientific validity of the conclusions, identify significant correlations between emissions and fuel or process parameters, compare the data with available data from EPRI studies, make recommendations for future studies, and complete a combined report that summarizes Phase I, Phase II, and EPRI findings.
Date: August 1, 1997
Creator: Ness, Sumitra R.
Partner: UNT Libraries Government Documents Department

Task 2.8 - Mercury Speciation and Capture in Scubber Solutions

Description: U.S. Environmental Protection Agency (EPA) investigation into health risks associated with mercury emissions from utility steam generators, municipal waste combustion units, and other sources was mandated by the Clean Air Act Amendments (CAAA) of 1990. In anticipation of mercury emission regulation, attention has been focused on quantification of mercury emissions, which require verifiable sampling and analytical techniques. Several sampling and analytical methods are currently under the final stages of development as well as a variety of emission control methods. In particular, wet scrubber systems designed for S2 control in coal-fired utilities have been targeted for mercury control. Conventional wet-scrubbers remove mercury in a variety of soluble oxidized forms. Oxidized mercury is highly water-soluble and can be removed by scrubber slurry, theoretically limited only by gas-film mass transfer. However, since some oxidized mercury forms such as HgClz are borh soluble and volatile, the final fate of mercury trapped in scrubber solutions is unclear. Elemental mercury is not water-soluble, remaining in the vapor state at temperatures through pollution control devices and exiting the stack into the environment. However, notable exceptions to this rule exist. Depending on the type of mercury-sampling method used, an increase ofs 10% in elemental mercury concentrations across wet scrubbers has been metiured but is yet unconllrmed. Also, significant amounts of elemental mercury (metallic form) have been removed during wet scrubber maintenance. In addition, questions concerning 1) the initial speciation between oxidized and elemental forms of mercury in flue gas from coal- fired boilers and 2) the effects of scrubber slurry composition and pH on the mercury species have been raised.
Date: August 1, 1997
Creator: Ness, Sumitra R.
Partner: UNT Libraries Government Documents Department

Task 2.10 - Advanced Sampling and Analysis of Fine Particulates

Description: The objectives of this study are to develop a sampling method to capture the fine particulate and classiyi the particulate according to their size and chemistry. When developing the sampling method, two criteria need to be met: 1) the particulate are randomly dispersed on the sampling media and 2) the sampling media can be put directly into a scanning electron microscope (SEM) for analysis to prevent any alteration of the particulate. Several methods for the sampling and analysis of fine particulate are to be tested. Each sampling test will be analyzed using the FPT technique for collecting the size, shape, and chemical composition of 1500 to 2000 individual fine particulate. The FPT data will be classified using cluster analysis and principal component analysis to provide a classification system for these particles. As reported previously, particulate samples were collected using the advanced hybrid particulate collector (AHPC) on the inlet port of the particulate test combustor (PTC) when the Absaloka coal was burned in early April. The samples were collected at the inlet rather than the outlet port because of the loading that was expected and the temperature at which the PTC was run. Samples at the inlet were expected to see a much greater particulate loading than at the outlet because of the efficiency of the particulate collection device on the PTC. Also, polycarbonate filters cannot withstand temperatures above 230oC for long periods of time; therefore, a quick loading time was required. The samples were briefly scanned and photographed using the SEM to determine the best particulate loading time. The particulate were too close together on the 20- and 30-second polycarbonate filters to be able to analyze individual particles. The particle dispersion on the vitreous carbon substrate appeared to be the best of the four samples. Aerosols were produced from pure ...
Date: January 1, 1998
Creator: McCollor, Donald P. & Eyland, Kurt E.
Partner: UNT Libraries Government Documents Department

Task 3.0 - Advanced Power Systems Subtask 3.18 - Ash Behavior in Power Systems

Description: Ash behavior in power systems can have a significant impact on the design and performance of advanced power systems. The Energy & Environmental Research Center (EERC) has focused significant effort on ash behavior in conventional power systems that can be applied to advanced power systems. This initiative focuses on filling gaps in the understanding of fundamental mechanisms of ash behavior that has relevance to commercial application and marketable products. This program develops methods and means to better understand and mitigate adverse coal ash behavior in power systems and can act to relieve the U.S. reliance on diminishing recoverable oil resources, especially those resources that are not domestically available and are fairly uncertain.
Date: July 1, 1997
Creator: Zygarlicke, Christopher J. & McCollor, Donald P.
Partner: UNT Libraries Government Documents Department

Characterization of Transport and Solidification in the Metal Recycling Processes

Description: The characterization of the transport and solidification of metal in the melting and casting processes is significant for the optimization of the radioactively contaminated metal recycling and refining processes. . In this research project, the transport process in the melting and solidification of metal was numerically predicted, and the microstructure and radionuclide distribution have been characterized by scanning electron microscope/electron diffractive X-ray (SEWEDX) analysis using cesium chloride (CSC1) as the radionuclide surrogate. In the melting and solidification process, a resistance furnace whose heating and cooling rates are program- controlled in the helium atmosphere was used. The characterization procedures included weighing, melting and solidification, weighing after solidification, sample preparation, and SEM/EDX analysis. This analytical methodology can be used to characterize metal recycling and refining products in order to evaluate the performance of the recycling process. The data obtained provide much valuable information that is necessary for the enhancement of radioactive contaminated metal decontamination and recycling technologies. The numerical method for the prediction of the melting and solidification process can be implemented in the control and monitoring system-of the melting and casting process in radioactive contaminated metal recycling. The use of radionuclide surrogates instead of real radionuclides enables the research to be performed without causing harmfid effects on people or the community. This characterization process has been conducted at the Hemispheric Center for Environmental Technology (HCET) at Florida International University since October 1995. Tests have been conducted on aluminum (Al) and copper (Cu) using cesium chloride (CSCI) as a radionuclide surrogate, and information regarding the radionuclide transfer and distribution in melting and solidification process has been obtained. The numerical simulation of the solidification of molten metal has been very successful for aluminium; however, a stability problem in the simulation of iron/steel solidification poses a challenge. Thus, additional development is needed to simulate ...
Date: August 6, 1997
Creator: Ebadian, M. A.; Xin, R. C. & Dong, Z. F.
Partner: UNT Libraries Government Documents Department

Development of a Gas-Promoted Oil Agglomeration Process

Description: Further agglomeration tests were conducted in a series of tests designed to determine the effects of various parameters on the size and structure of the agglomerates formed, the rate of agglomeration, coal recovery, and ash rejection. For this series of tests, finely ground Pittsburgh No. 8 coal has been agglomerated with i-octane in a closed mixing system with a controlled amount of air present to promote particle agglomeration. The present results provide further evidence of the role played by air. As the concentration of air in the system was increased from 4.5 to 18 v/w% based on the weight of coal, coal recovery and ash rejection both increased. The results also show that coal recovery and ash rejection were improved by increasing agitator speed. On the other hand, coal recovery was not affected by a change in solids concentration from 20 to 30 w/w%.
Date: October 30, 1998
Creator: Shen, M. & Wheelock, T. D.
Partner: UNT Libraries Government Documents Department

MAINTENANCE OF THE COAL SAMPLE BANK AND DATABASE

Description: This project generates and provides coal samples and accompanying analytical data for research by DOE contractors and others. The five-year contract has been completed and a six-month no-cost extension is under way; this will continue the limited distribution of samples and data to DOE, its contractors and grantees. All activities specified under the five-year contract have been completed. Eleven DECS samples were collected, processed to a variety of particle sizes, heat-sealed in foil laminate bags under argon, and placed in refrigerated storage. All were analyzed for basic chemical composition, inorganic major and trace element composition including hazardous air pollutant elements, petrographic composition and characteristics, thermoplastic behavior (if applicable), and other properties relevant to commercial utilization. Most were also analyzed by NMR, py/gc/ms, and a standardized liquefaction test; trends and relationships observed were evaluated and summarized. Twenty-two DECS samples collected under the previous contract received further processing, and most of these were subjected to organic geochemical and standardized liquefaction tests as well. Selected DECS samples were monitored annually to evaluate the effectiveness of foil laminate bags for long-term sample storage. Twenty-three PSOC samples collected under previous contracts and purged with argon before storage were also maintained and distributed, for a total of 56 samples covered by the contract. During the five years, 524 samples in 1501 containers, 2075 data printouts, and individual data items from 30327 samples were distributed. In the subject quarter, 45 samples, 101 data printouts, and individual data items from 1237 samples were distributed. Splits of the last two samples from the previous contract received processing to minus 0.25 mm; all DECS samples are now available for immediate distribution at minus 6 mm (-1/4 inch), minus 0.85 mm (- 20 mesh U.S.), and minus 0.25 mm (minus 60 mesh U.S.). The final annual monitoring of foil laminate bag ...
Date: October 1, 1998
Partner: UNT Libraries Government Documents Department

A NOVEL APPROACH TO CATALYTIC DESULFURIZATION OF COAL

Description: Efforts toward quantitation of the sulfur removed from coal in the reaction Coal(S) + excess PBu3 {yields}heat Coal + SPBu3 /PBu3 by column chromatography of the products followed by weighing the SPBu3 and vacuum distillation of the SPBu3/PBu3 mixture followed by gas chromatographic analysis are described. The first method failed, but the latter is more successful. It has been discovered that para-chloro phenol catalyzes the removal of sulfur from dibenzothiophene by PBu3 under mild conditions.
Date: May 31, 1996
Partner: UNT Libraries Government Documents Department

Mining and Reclamation Technology Symposium

Description: The Mining and Reclamation Technology Symposium was commissioned by the Mountaintop Removal Mining/Valley Fill Environmental Impact Statement (EIS) Interagency Steering Committee as an educational forum for the members of the regulatory community who will participate in the development of the EIS. The Steering Committee sought a balanced audience to ensure the input to the regulatory community reflected the range of perspectives on this complicated and emotional issue. The focus of this symposium is on mining and reclamation technology alternatives, which is one of eleven topics scheduled for review to support development of the EIS. Others include hydrologic, environmental, ecological, and socio-economic issues.
Date: June 24, 1999
Partner: UNT Libraries Government Documents Department

Riverton Dome Gas Exploration and Stimulation Technology Demonstration, Wind River Basin, Wyoming

Description: This project will provide a full demonstration of an entirely new package of exploration technologies that will result in the discovery and development of significant new gas reserves now trapped in unconventional low-permeability reservoirs. This demonstration includes the field application of these technologies, prospect definition and well siting, and a test of this new strategy through wildcat drilling. In addition this project includes a demonstration of a new stimulation technology that will improve completion success in these unconventional low permeability reservoirs which are sensitive to drilling and completion damage. The work includes two test wells to be drilled by Snyder Oil Company on the Shoshone/Arapahoe Tribal Lands in the Wind River Basin. This basin is a foreland basin whose petroleum systems include Paleozoic and Cretaceous source beds and reservoirs which were buried, folded by Laramide compressional folding, and subsequently uplifted asymmetrically. The anomalous pressure boundary is also asymmetric, following differential uplift trends. The Institute for Energy Research has taken a unique approach to building a new exploration strategy for low-permeability gas accumulations in basins characterized by anomalously pressured, compartmentalized gas accumulations. Key to this approach is the determination and three-dimensional evaluation of the pressure boundary between normal and anomalous pressure regimes, and the detection and delineation of areas of enhanced storage capacity and deliverability below this boundary. This new exploration strategy will be demonstrated in the Riverton Dome� Emigrant Demonstration Project (RDEDP) by completing the following tasks: 1) detect and delineate the anomalous pressure boundaries, 2) delineate surface lineaments, fracture and fault distribution, spacing, and orientation through remote sensing investigations, 3) characterize the internal structure of the anomalous pressured volume in the RDEDP and determine the scale of compartmentalization using produced water chemistry, 4) define the prospects and well locations as a result on this new exploration technology, and 5) ...
Date: November 15, 1998
Creator: Surdam, Ronald C.
Partner: UNT Libraries Government Documents Department

Sixteenth Quarterly Report Regulation of Coal Polymer Degradation by Fungi

Description: Three phenomena which concern coal solubilization and depolymerization were studied during this reporting period. Previous investigations have shown that lignin peroxidases mediate the oxidation of soluble coal macromolecule. Because it appears to be a substrate, soluble coal macromolecule is also an inhibitor of veratryl alcohol oxidation, a reaction that is mediated by these enzymes. The mechanism of inhibition is complex in that oxidation (as assayed by decolorization) of soluble coal macromolecule requires the presence of veratryl alcohol and veratryl alcohol oxidation occurs only after a substantial lag period during which the soluble coal macromolecule is oxidized. In a previous quarterly report we proposed a reaction mechanism by which this may occur. During the present reporting period we showed that our proposed reaction mechanism is consistent with classical enzyme kinetic theory describing enzyme activity in the presence of a potent inhibitor (i.e., an inhibitor with a very low KI ). The oxidative decolorization and depolymerization of soluble coal macromolecule was also studied. Because wood rotting fungi produce hydrogen peroxide via a variety of reactions, we studied the effect of hydrogen peroxide on soluble coal macromolecule decolorization and depolymerization. Results showed that substantial decolorization occurred only at hydrogen peroxide concentrations that are clearly non-physiological (i.e., 50 mM or greater). It was noted, however, that when grown on solid lignocellulosic substrates, wood rotting fungi, overtime, cumulatively could produce amounts of hydrogen peroxide that might cause significant oxidative degradation of soluble coal macromolecule. Thirdly, we have shown that during oxalate mediated solubilization of low rank coal, a pH increase is observed. During this reporting period we have shown that the pH of solutions containing only sodium oxalate also undergo an increase in pH, but to a lesser extent than that observed in mixtures containing sodium oxalate and low rank coal. It is our hypothesis ...
Date: July 31, 1998
Creator: Bumpus, John A.
Partner: UNT Libraries Government Documents Department

SO2 REMOVAL FROM FLUE GASES USING UTILITY SYNTHESIZED ZEOLITES

Description: It is well known that natural and synthetic zeolites (molecular sieves) can adsorb gaseous SO<sub>2</sub> from flue gas and do it more efficiently than lime based scrubbing materials. Unfortunately their cost ($500-$800 per ton) has deterred their use in this capacity. It is also known that zeolites are easy to synthesize from a variety of natural and man-made materials. The overall objective of the current work has been to evaluate the feasibility of having a utility synthesize its own zeolites, on-site, from fly ash and other recycled materials and then use these zeolites to adsorb SO<sub>2</sub> from their flue gases. Work to date has shown that the efficiency of the capture process is related to the degree of crystallinity and the type of zeolite that forms in the samples. Normally, those samples cured at 150°C contained a greater proportion of zeolite and as such were more SO<sub>2</sub> adsorptive than their low-temperature counterparts. However, in order for the project to be successful, on site synthesis must remain an option, i.e. _100°C synthesis. In light of this, the experimental focus now has two aspects. First, compositions of the starting materials are being altered by blending the current suite of fly ashes with other fly ashes, ground glass cullet and silica fume to promote the formation and growth of well crystallized and highly adsorptive zeolites. Second, greater degrees of reaction at significantly lower temperatures are being promote by ball milling the fly ash prior to use, by the use of more concentrated caustic solutions, and by the addition of zeolite seeds to the reactants. In all cases studies will focus on the effect of structure type and degree of conversion on SO<sub>2</sub> adsorption. Future work will concentrate on the study of the effect of weathering on the suitability of converting fly ash into ...
Date: October 31, 1998
Creator: GRUTZECK, MICHAEL
Partner: UNT Libraries Government Documents Department

INVESTIGATION ON DURABILITY AND REACTIVITY OF PROMISING METAL OXIDE SORBENTS DURING SULFIDATION AND REGENERATION

Description: The main objective of this research project during this quarter is to investigate effects of hydrogen on initial absorption as well as equilibrium absorption of 2500-ppm H2S into 0.1-g TU-188 sorbent in the presence of 10 vol % moisture at the 0.12-s space time and 530 o C.
Date: August 1, 1998
Creator: Kwon, K. C.
Partner: UNT Libraries Government Documents Department

INVESTIGATION ON DURABILITY AND REACTIVITY OF PROMISING METAL OXIDE SORBENTS DURING SULFIDATION AND REGENERATION

Description: The main objectives of this research project during this quarter are to investigate effects of hydrogen, moisture, concentrations of H<sub>2</sub> S, and residence time of reaction gas mixtures on equilibrium absorption as well as dynamic absorption of H<sub>2</sub> S into the TU-188 sorbent at 530 o C, and to evaluate effective diffusivity of H<sub>2</sub> S through the sorbent particles, using the newly-fabricated differential reactor.
Date: December 1, 1997
Creator: KWON, K.C.
Partner: UNT Libraries Government Documents Department

MAINTENANCE OF THE COAL SAMPLE BANK AND DATABASE

Description: This project generates and provides coal samples and accompanying analytical data for research by DOE contractors and others. The five-year contract has been completed and a six-month no-cost extension is under way; this will continue the limited distribution of samples and data to DOE, its contractors and grantees. All activities specified under the five-year contract have been completed. Eleven DECS samples were collected, processed to a variety of particle sizes, heat-sealed in foil laminate bags under argon, and placed in refrigerated storage. All were analyzed for basic chemical composition, inorganic major and trace element composition including hazardous air pollutant elements, petrographic composition and characteristics, thermoplastic behavior (if applicable), and other properties relevant to commercial utilization. Most were also analyzed by NMR, py/gc/ms, and a standardized liquefaction test; trends and relationships observed were evaluated and summarized. Twenty-two DECS samples collected under the previous contract received further processing, and most of these were subjected to organic geochemical and standardized liquefaction tests as well. Selected DECS samples were monitored annually to evaluate the effectiveness of foil laminate bags for long-term sample storage. Twenty-three PSOC samples collected under previous contracts and purged with argon before storage were also maintained and distributed, for a total of 56 samples covered by the contract. During the five years, 524 samples in 1501 containers, 2075 data printouts, and individual data items from 30327 samples were distributed. In the subject quarter, 23 samples, 16 data printouts, and individual data items from 2507 samples were distributed. All DECS samples are now available for immediate distribution at minus 6 mm (-1/4 inch), minus 0.85 mm (- 20 mesh U.S.), and minus 0.25 mm (- 60 mesh U.S.).
Date: January 1, 1999
Partner: UNT Libraries Government Documents Department

SYNTHESIS OF METHYL METHACRYLATE FROM COAL-DERIVED SYNGAS

Description: Research Triangle Institute (RTI), Eastman Chemical Company, and Bechtel collectively are developing a novel three-step process for the synthesis of methyl methacrylate (MMA) from coal-derived syngas that consists of the steps of synthesis of a propionate, its condensation with formaldehyde to form methacrylic acid (MAA), and esterification of MAA with methanol to produce MMA. The research team has completed the research on the three-step methanol-based route to MMA. Under an extension to the original contract, we are currently evaluating a new DME-based process for MMA. The key research need for DME route is to develop catalysts for DME partial oxidation reactions and DME condensation reactions. Over the last quarter(Oct.-Dec./98), we have investigated the condensation between methyl propionate and formaldehyde (MP/HCHO=4.5/1) at various reaction temperatures(280-360EC) over 5%, 10%, and 20% Nb O /SiO catalysts. The conversion of HCHO increases with reaction 2 5 2 temperature and niobium loading. MMA+MAA selectivity goes through a maximum with the temperature over both 10% and 20% Nb O /SiO . The selectivities to MMA+MAA are 67.2%, 2 5 2 72.3%and 58.1% at 320EC over 5%, 10%, 20% Nb O /SiO , respectively. However, the 2 5 2 conversion of formaldehyde decreases rapidly with time on stream. The results suggest that silica supported niobium catalysts are active and selective for condensation of MP with HCHO, but deactivation needs to be minimized for the consideration of commercial application. We have preliminarily investigated the partial oxidation of dimethyl ether(DME) over 5% Nb O /SiO catalyst. Reactant gas mixture of 0.1% DME, 0.1% O and balance nitrogen is 2 5 2 2 studied with temperature ranging from 200°C to 500°C. The conversion of DME first increases with temperature reaching an maximum at 400°C then decreases. The selectivity to HCHO also increases with reaction temperature first. But the selectivity to ...
Date: January 20, 1999
Creator: JANG, BEN W.-L.; CHOI, GERALD N.; SPIVEY, JAMES J.; ZOELLER, JOSPEH R. & COLBERG, RICHARD D.
Partner: UNT Libraries Government Documents Department

Task 37 - Ash Deposition Course

Description: The goals of this Energy & Environmental Research Center project are to develop a short course for transferring technical information from the research community to the industrial community, to seek out the research needs of industry, and to continually upgrade course materials. The Coal Ash Behavior and Deposition short course developed in the project provides an overview of recent research that is increasing the understanding of mineral behavior in coal utilization. This research leads to the advancement of methods to predict ash behavior, which can economically resolve fouling problems for the utility industry.
Date: December 31, 1998
Creator: Brekke, David W.
Partner: UNT Libraries Government Documents Department

Poc-Scale Testing of an Advanced Fine Coal Dewatering Equipment/Technique

Description: In the last quarterly report, it was noticed that the baseline dewatering data varied significantly. This abnormality was attributed to the use of house vacuum which varied significantly during the testing. This quarter tests were repeated using a portable vacuum pump which provided a constant vacuum of 25 inches of mercury. Using 30 secs cake drying time and 30 secs cake formation time, the high- and low-porosity ceramic leaf filters provided 21.5% and 18.0% filter cake moistures, respectively. The solids loading on the high- and low-porosity filters were 0.8 Kg/m 2 and 0.44 Kg/m 2 , respectively. Addition of 10 g/t of an anionic flocculant lowered the filter cake moisture from 22.0% to 14.0% using the high-porosity filter, and 18.0% to 13.5% using the low-porosity filter. Addition of 15 g/t of a cationic flocculant lowered filter cake moisture from 18.0% to 16.0% using the low-porosity filter. High-porosity filter did not provide any lowering of filter cake moisture, however, the solids loading increased from 1.5 kg/m 2 to 5.8 kg/m 2 at a flocculant dosage of 25 g/t. This high solids loading indicated thicker filter cake which would retain a high moisture. Among the three surfactants studied, only the non-ionic and the cationic were effective in lowering the filter cake moisture. 0.4 kg/t of a non-ionic surfactant (octyl phenoxy polyethoxy ethanol) lowered filter cake moisture from 19.5% to 16.8%; and 1 kg/t of the cationic surfactant CPCL, lowered the filter cake moisture from 19.0% to 15.8%. Addition of 0.4 kg/t of copper ions or 0.3 kg/t of aluminum ions lowered the filter cake moisture from 20.5% to 17.0%, using the low-porosity filter. The high-porosity filter which showed increase solids loading (thicker filter cakes) did not provide any lowering of the filter cake moisture. Low-porosity filter was found to be more effective ...
Date: October 21, 1998
Creator: Parekh, B.K.; Tao, D. & Groppo, J.G.
Partner: UNT Libraries Government Documents Department