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Catalytic fabric filtration for simultaneous NO{sub x} and particulate control. Quarterly technical progress report, October 1, 1991--December 31, 1991

Description: The overall objective of this project is the development of a catalytic fabric filter for simultaneous NO{sub x} and particulate control. The catalytic fabric filter must provide high removal efficiency of NO{sub x} and particulate matter. An acceptable bag and catalyst life must be demonstrated, and process economics must show a significant cost savings when compared to a commercial SCR process and conventional particulate control. Specific goals include the following: (1) Reduce NO{sub x} emissions to 60 ppm or less. (2) Demonstrate particulate removal efficiency of >99.5%. (3) Demonstrate a bag/catalyst life of >1 year. (4) Control ammonia slip to >25 ppm. (5) Show that catalytic fabric filtration can achieve a 50% cost savings over conventional fabric filtration and SCR control technology. (6) Determine compatibility with SO{sub 2} removal systems. (7) Show that the concept results in a nonhazardous waste product.
Date: February 1, 1992
Creator: Weber, G. F.; Ness, S. R.; Laudal, D. L. & Dunham, G.

Chaotic vibrations of nonlinearly supported tubes in crossflow

Description: By means of the unsteady-flow theory and a bilinear mathematical model, a theoretical study is presented for chaotic vibrations associated with the fluidelastic instability of nonlinearly supported tubes in a crossflow. Effective tools, including phase portraits, power spectral density, Poincare maps, Lyapunov exponent, fractal dimension, and bifurcation diagrams, are utilized to distinguish periodic and chaotic motions when the tubes vibrate in the instability region. The results show periodic and chaotic motions in the region corresponding to fluid-damping-controlled instability. Nonlinear supports, with symmetric or asymmetric gaps, significantly affect the distribution of periodic, quasiperiodic, and chaotic motions of a tube exposed to various flow velocities in the instability region of the tube-support-plate-inactive mode.
Date: February 1, 1992
Creator: Cai, Y. & Chen, S.S.

Chaotic Vibrations of Nonlinearly Supported Tubes in Crossflow

Description: By means of the unsteady-flow theory and a bilinear mathematical model, a theoretical study is presented for chaotic vibrations associated with the fluid-elastic instability of nonlinearly supported tubes in a crossflow. Effective tools, including phase portraits, power spectral density, Poincare maps, Lyapunov exponent, fractal dimension, and bifurcation diagrams, are utilized to distinguish periodic and chaotic motions when the tubes vibrate in the instability region. The results show periodic and chaotic motions in the region corresponding to fluid-damping-controlled instability. Nonlinear supports, with symmetric or asymmetric gaps, significantly affect the distribution of periodic, quasi-periodic, and chaotic motions of a tube exposed to various flow velocities in the instability region of the tube-support-plate-inactive mode.
Date: February 1992
Creator: Cai, Y. & Chen, Shoei-Sheng

Chaotic vibrations of nonlinearly supported tubes in crossflow

Description: By means of the unsteady-flow theory and a bilinear mathematical model, a theoretical study is presented for chaotic vibrations associated with the fluidelastic instability of nonlinearly supported tubes in a crossflow. Effective tools, including phase portraits, power spectral density, Poincare maps, Lyapunov exponent, fractal dimension, and bifurcation diagrams, are utilized to distinguish periodic and chaotic motions when the tubes vibrate in the instability region. The results show periodic and chaotic motions in the region corresponding to fluid-damping-controlled instability. Nonlinear supports, with symmetric or asymmetric gaps, significantly affect the distribution of periodic, quasiperiodic, and chaotic motions of a tube exposed to various flow velocities in the instability region of the tube-support-plate-inactive mode.
Date: February 1, 1992
Creator: Cai, Y. & Chen, S. S.

Characterization of core debris/concrete interactions for the Advanced Neutron Source

Description: This report provides the results of a recent study conducted to explore the molten core/concrete interaction (MCCI) issue for the Advanced Neutron Source (ANS). The need for such a study arises from the potential threats to reactor system integrity posed by MCCI. These threats include direct attack of the concrete basemat of the containment; generation and release of large quantities of gas that can pressurize the containment; the combustion threat of these gases; and the potential generation, release, and transport of radioactive aerosols to the environment.
Date: February 1, 1992
Creator: Hyman, C. R. & Taleyarkhan, R. P.

Characterization of core debris/concrete interactions for the Advanced Neutron Source. ANS Severe Accident Analysis Program

Description: This report provides the results of a recent study conducted to explore the molten core/concrete interaction (MCCI) issue for the Advanced Neutron Source (ANS). The need for such a study arises from the potential threats to reactor system integrity posed by MCCI. These threats include direct attack of the concrete basemat of the containment; generation and release of large quantities of gas that can pressurize the containment; the combustion threat of these gases; and the potential generation, release, and transport of radioactive aerosols to the environment.
Date: February 1, 1992
Creator: Hyman, C. R. & Taleyarkhan, R. P.

Characterization of the Weatherization Assistance Program network

Description: The Characterization of the Weatherization Assistance Program (WAP) Network was designed to describe the national network of State and local agencies that provide WAP services to qualifying low-income households. The objective of this study was to profile the current WAP network. To achieve the objective, two national surveys were conducted: one survey collected data from 49 State WAP agencies (including the coterminous 48 States and the District of Columbia), and the second survey collected data from 920 (or 81 percent) of the local WAP agencies.
Date: February 1, 1992
Creator: Mihlmester, P.E.; Koehler, W.C. Jr.; Beyer, M.A. (Aspen Systems Corp., Oak Ridge, TN (United States). Applied Management Sciences Div.); Brown, M.A. (Oak Ridge National Lab., TN (United States)) & Beschen, D.A. Jr. (Department of Energy, Washington, DC (United States). Office of Weatherization Assistance Programs)

Characterization of the Weatherization Assistance Program network. Weatherization Assistance Program

Description: The Characterization of the Weatherization Assistance Program (WAP) Network was designed to describe the national network of State and local agencies that provide WAP services to qualifying low-income households. The objective of this study was to profile the current WAP network. To achieve the objective, two national surveys were conducted: one survey collected data from 49 State WAP agencies (including the coterminous 48 States and the District of Columbia), and the second survey collected data from 920 (or 81 percent) of the local WAP agencies.
Date: February 1, 1992
Creator: Mihlmester, P. E.; Koehler, W. C. Jr.; Beyer, M. A.; Brown, M. A. & Beschen, D. A. Jr.

The chemical enhancement of the triboelectric separation of coal from pyrite and ash: A novel approach for electrostatic separation of mineral matter from coal

Description: Arthur D. Little, Inc., under contract to the US DOE Pittsburgh Energy Technology Center, has developed a triboelectric separation device for coal beneficiation, that employs an entrained-flow, rotating-cylinder concept. The described apparatus has been used to test the efficacy of chemical pretreatment and in-situ treatment of coal on separation efficiency. Coal particle entrainment is achieved with gaseous carbon dioxide and particle collection is accomplished by an electrostatic plate separator. The triboelectric separation device incorporates instrumentation for the direct measurement of charge in the dilute-phase particle stream. Some of the pretreatment materials investigated under this project to modify the surface charging characteristics of the coal included oleic acid, sodium oleate, quinoline and dicyclohexylamine. Ammonia and sulfur dioxide at a concentration up to 1000 ppM was used for in-situ treatment of the coal, with carbon dioxide as the carrier/inerting gas. Nitrogen was used earlier in the test program as the carrier/inerting gas for the coal, but a severe arcing problem was encountered in the electrostatic collector with nitrogen as the carrier gas. This problem did not occur when carbon dioxide was used. The report covers the chemical treatment employed, and summarizes and interprets the results achieved. In addition, an economic analysis of a full scale system based on this concept is presented.
Date: February 1, 1992
Creator: Gustafson, R.M.; DiMare, S. & Sabatini, J.

The chemical enhancement of the triboelectric separation of coal from pyrite and ash: A novel approach for electrostatic separation of mineral matter from coal. Final report

Description: Arthur D. Little, Inc., under contract to the US DOE Pittsburgh Energy Technology Center, has developed a triboelectric separation device for coal beneficiation, that employs an entrained-flow, rotating-cylinder concept. The described apparatus has been used to test the efficacy of chemical pretreatment and in-situ treatment of coal on separation efficiency. Coal particle entrainment is achieved with gaseous carbon dioxide and particle collection is accomplished by an electrostatic plate separator. The triboelectric separation device incorporates instrumentation for the direct measurement of charge in the dilute-phase particle stream. Some of the pretreatment materials investigated under this project to modify the surface charging characteristics of the coal included oleic acid, sodium oleate, quinoline and dicyclohexylamine. Ammonia and sulfur dioxide at a concentration up to 1000 ppM was used for in-situ treatment of the coal, with carbon dioxide as the carrier/inerting gas. Nitrogen was used earlier in the test program as the carrier/inerting gas for the coal, but a severe arcing problem was encountered in the electrostatic collector with nitrogen as the carrier gas. This problem did not occur when carbon dioxide was used. The report covers the chemical treatment employed, and summarizes and interprets the results achieved. In addition, an economic analysis of a full scale system based on this concept is presented.
Date: February 1, 1992
Creator: Gustafson, R. M.; DiMare, S. & Sabatini, J.

Chemical interactions in multimetal/zeolite catalysts

Description: For Pt/NaY catalysts our analysis of the mechanism of metal particle formation has enabled us to produce at will samples which contain either the majority of the Pt particles in supercages, without filling these cages completely, or the Pt particles bulge into neighboring cages. The catalytic selectivity is distinctly different for these preparations, in the former case molecules can enter a supercage which is partially filled by the Pt cluster, in the second case adsorption takes place through the cage window. Applying the same principles of catalyst preparation of bimetallic catalysts enables us to produce PtCu particles in supercages of NaY, which contain, initially a Pt core, surrounded by a Cu mantle. Earlier we have found that Ni ions migrate into hexagonal prisms during calcination of Ni/NaY; this process can be partially suppressed by first filling these prisms with Mn or Cr ions. In more recent work we found that addition of Pt strongly lowers the temperature of Ni reduction. Part of the Ni ions is reduced by hydrogen while still inside the smaller cages. This reduction process is, however, reversible; at elevated temperature and in an inert atmosphere protons re-oxidize the Ni atoms and dihydrogen gas is developed. In this way it seems possible to count the Ni atoms in small cages. The calcination stage in the preparation of zeolite supported metals has been studied in considerable detail for Pd/NaY. The Pd is introduced as a tetrammin complex; during calcination the ammine ligands are successively oxidized. Once three ammine ligands are destroyed, the Pd ions which carry only one ligand, surprisingly jump from the supercages to the sodalite cage.
Date: February 7, 1992
Creator: Sachtler, W.M.H.

Chemical interactions in multimetal/zeolite catalysts

Description: This report treats four subject areas: PtCu/NaY and Pd/Cu/NaY catalysts; reducibility of Ni in PdNi/NaY catalysts; CO hydrogenation over PdNi/NaY catalysts; and PdFe/NaY, Ga/H-ZSM5 and PtGa/H-ZSM5 catalysts.
Date: February 7, 1992
Creator: Sachtler, W.M.H.

Chemical interactions in multimetal/zeolite catalysts

Description: Mechanistic explanations have been found for the migration of atoms and ions through the zeolite channels leading to specific distribution of ions and the metal clusters. In this report, we summarize the state of understanding attained on a number of topics in the area of mono- and multimetal/zeolite systems, to which our recent research has made significant contributions. The following topics are discussed: (1) Formation of isolated metal atoms in sodalite cages; (2) differences of metal/zeolite systems prepared by ion reduction in channels or via isolated atoms; (3) rejuvenation of Pd/NaY and Pd/HY catalysts by oxidative redispersion of the metal; (4) formation of mono- or bimetal particles in zeolites by programmed reductive decomposition of volatile metal complexes; (5) cation-cation interaction as a cause of enhanced reducibility; (6) formation of palladium carbonyl clusters in supercages; (7) enhanced catalytic activity of metal particle-proton complexes for hydrocarbon conversion reactions; (8) stereoselectivity of catalytic reactions due to geometric constraints of particles in cages.
Date: February 7, 1992
Creator: Sachtler, W.M.H.

Clean Coal Technology III (CCT III) 10 MW demonstration of gas suspension absorption

Description: The Gas Suspension Absorber (GSA) system brings coal combustion gases into contact with a suspended mixture of solids, including sulfur-absorbing lime. After the lime absorbs the sulfur pollutants, the solids are separated from the gases in a cyclone device and recirculated back into the system where they capture additional sulfur pollutant. The cleaned flue gases are sent through a dust collector before being released into the atmosphere. The key to the system's superior economic performance with high sulfur coals is the recirculation of solids. Typically, a solid particle will pass through the system about one hundred times before leaving the system. Another advantage of the GSA system is that a single spray nozzle is used to inject fresh lime slurry. The GSA system is expected to be the answer to the need of the US industry for an effective, economic and space efficient solution to the SO{sub 2} pollution problem.
Date: February 7, 1992

Clean Coal Technology III (CCT III) 10 MW demonstration of gas suspension absorption. Fourth quarterly technical progress report, July 1, 1991--September 30, 1991

Description: The Gas Suspension Absorber (GSA) system brings coal combustion gases into contact with a suspended mixture of solids, including sulfur-absorbing lime. After the lime absorbs the sulfur pollutants, the solids are separated from the gases in a cyclone device and recirculated back into the system where they capture additional sulfur pollutant. The cleaned flue gases are sent through a dust collector before being released into the atmosphere. The key to the system`s superior economic performance with high sulfur coals is the recirculation of solids. Typically, a solid particle will pass through the system about one hundred times before leaving the system. Another advantage of the GSA system is that a single spray nozzle is used to inject fresh lime slurry. The GSA system is expected to be the answer to the need of the US industry for an effective, economic and space efficient solution to the SO{sub 2} pollution problem.
Date: February 7, 1992

Cleavage and crosslinking of polymeric coal structures during pyrolysis

Description: The ultimate objective of this project was to develop a better understanding of volatiles production to help optimize the yield and character of condensable coproducts during coal pyrolysis or mild gasification. The specific objectives were to (1) Develop pyrolysis procedures that minimize secondary reactions; and (2) Develop coal pretreatments that current knowledge suggests will prorate bond scission or prevent retrograde reactions. Our approach was to study the pyrolysis of coals and tar-loaded coals by using several techniques that span a range of heating rates and pressures. Slow-heating pyrolyses were performed at low pressures in the inlet of a field ionization mass spectrometer and at atmospheric pressures in a thermogravimetric analyzer. Moderately rapid-heating pyrolyses were performed in a vacuum TGA apparatus and in sealed silica ampules heated in a molten-salt bath. The fastest heating rates were achieved with laser pyrolysis at about 30,000 X/s. The high tar yield seen in this work where the entire volume of the coal particle becomes hot and fluid at very nearly the same time, taken together with the evident non-vapor transport of the tar under these conditions, emphasizes the importance of better understanding the development of fluidity during coal heating. This specifically includes the profound effects--long-recognized but poorly understood that mild oxidation has in suppressing coal fluidity. It also includes the more recently recognized fact that heating in the presence of an inert gas produced substantially greater fluidity than does heating in the presence of combustion gases, even if the conditions are very fuel rich and all the oxygen itself has already been consumed when the coal particles are encountered.
Date: February 1, 1992
Creator: McMillen, D. F. & Malhotra, R.

Cleavage and crosslinking of polymeric coal structures during pyrolysis. Final report

Description: The ultimate objective of this project was to develop a better understanding of volatiles production to help optimize the yield and character of condensable coproducts during coal pyrolysis or mild gasification. The specific objectives were to (1) Develop pyrolysis procedures that minimize secondary reactions; and (2) Develop coal pretreatments that current knowledge suggests will prorate bond scission or prevent retrograde reactions. Our approach was to study the pyrolysis of coals and tar-loaded coals by using several techniques that span a range of heating rates and pressures. Slow-heating pyrolyses were performed at low pressures in the inlet of a field ionization mass spectrometer and at atmospheric pressures in a thermogravimetric analyzer. Moderately rapid-heating pyrolyses were performed in a vacuum TGA apparatus and in sealed silica ampules heated in a molten-salt bath. The fastest heating rates were achieved with laser pyrolysis at about 30,000 X/s. The high tar yield seen in this work where the entire volume of the coal particle becomes hot and fluid at very nearly the same time, taken together with the evident non-vapor transport of the tar under these conditions, emphasizes the importance of better understanding the development of fluidity during coal heating. This specifically includes the profound effects--long-recognized but poorly understood that mild oxidation has in suppressing coal fluidity. It also includes the more recently recognized fact that heating in the presence of an inert gas produced substantially greater fluidity than does heating in the presence of combustion gases, even if the conditions are very fuel rich and all the oxygen itself has already been consumed when the coal particles are encountered.
Date: February 1, 1992
Creator: McMillen, D. F. & Malhotra, R.

Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. [Pseudomonas, Thiobacillus, Rhodococcus]

Description: The original conception of the work was that genetic determinants of the sulfoxide/sulfone/sulfonate/sulfate ( 4S'') pathway in Pseudomonas spp. would be cloned in vivo and then transferred to Thiobacillus spp. This ambition remains an appealing prospect; however, fulfilling that ambition has been confounded by an instability observed in the DbtS{sup +} phenotype in Pseudomonas spp. But the persisting interest in the phenotype has lead to isolation of fresh strains which have a DbtS{sup +} phenotype. One strain in particular, N1-36, has been the focus of extensive characterizations in long-term cultures. During the present quarter, seven cultures maintained in a fermentor'' for a week or longer have been run to determine rate and extent of growth, extent of conversion of dibenzothiophene (DBT) or dibenzosulfone (DBTO{sub 2}) to monohydroxybiphenyl (OH-BP), effect of pH maintained at 6.0, and the effect of adding glucose to cultures in which the amount of glucose had been diminished by bacterial consumption. In addition, a study of the effectiveness of using R68.445 as a vehicle for in vivo cloning of genes was completed this semester, and introduction of DbtS{sup +} determinants into Thiobacillus spp. continues to be an important goal.
Date: February 7, 1992
Creator: Krawiec, S.

Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. Tenth quarterly report

Description: The original conception of the work was that genetic determinants of the sulfoxide/sulfone/sulfonate/sulfate (``4S``) pathway in Pseudomonas spp. would be cloned in vivo and then transferred to Thiobacillus spp. This ambition remains an appealing prospect; however, fulfilling that ambition has been confounded by an instability observed in the DbtS{sup +} phenotype in Pseudomonas spp. But the persisting interest in the phenotype has lead to isolation of fresh strains which have a DbtS{sup +} phenotype. One strain in particular, N1-36, has been the focus of extensive characterizations in long-term cultures. During the present quarter, seven cultures maintained in a ``fermentor`` for a week or longer have been run to determine rate and extent of growth, extent of conversion of dibenzothiophene (DBT) or dibenzosulfone (DBTO{sub 2}) to monohydroxybiphenyl (OH-BP), effect of pH maintained at 6.0, and the effect of adding glucose to cultures in which the amount of glucose had been diminished by bacterial consumption. In addition, a study of the effectiveness of using R68.445 as a vehicle for in vivo cloning of genes was completed this semester, and introduction of DbtS{sup +} determinants into Thiobacillus spp. continues to be an important goal.
Date: February 7, 1992
Creator: Krawiec, S.

Coal plasticity at high heating rates and temperatures

Description: Using a high temperature plastometer with a new cone-shaped shearing disk, the effect of shear rate ({gamma}R) on the apparent viscosity of softened coal was studied. For {gamma}R from 2.01 s{sup {minus}1} to 10.7 s{sup {minus}1}, no shear rate effect on the viscosity of Pittsburgh No. 8 high volatile bituminous coal was observed. Three other coals, each of different ranks ranging from high volatile bituminous to low volatile bituminous, were also studied. Although lower in tar and extractable yields than high volatile bituminous coals, medium and low volatile bituminous coals were found to be very plastic. Their good plastic behavior is therefore hypothesized to arise from their ability to generate higher molecular weight liquid fragments ( macrometaplast'') which are not represented by tar and extractable yields.
Date: February 1, 1992
Creator: Gerjarusak, S.; Peters, W.A. & Howard, J.B.

Coal plasticity at high heating rates and temperatures. Seventh Technical progress report

Description: Using a high temperature plastometer with a new cone-shaped shearing disk, the effect of shear rate ({gamma}R) on the apparent viscosity of softened coal was studied. For {gamma}R from 2.01 s{sup {minus}1} to 10.7 s{sup {minus}1}, no shear rate effect on the viscosity of Pittsburgh No. 8 high volatile bituminous coal was observed. Three other coals, each of different ranks ranging from high volatile bituminous to low volatile bituminous, were also studied. Although lower in tar and extractable yields than high volatile bituminous coals, medium and low volatile bituminous coals were found to be very plastic. Their good plastic behavior is therefore hypothesized to arise from their ability to generate higher molecular weight liquid fragments (``macrometaplast``) which are not represented by tar and extractable yields.
Date: February 1, 1992
Creator: Gerjarusak, S.; Peters, W. A. & Howard, J. B.

Colorado School of Mines fusion gamma ray diagnostic project

Description: This report summarizes the 1991 calendar year activities of the fusion gamma ray diagnostics project in the Physics Department at the Colorado School of Mines. Considerable progress has been realized in the fusion gamma ray diagnostic project in the last year. Specifically we have achieved the two major goals of the project as outlined in last year's proposed work statement to the Office of Applied Plasma Physics in the DOE Division of Magnetic Fusion Energy. The two major goals were: (1) Solution of the severe interference problem encountered during the operation of the gamma ray spectrometer concurrent with high power levels of the neutral beam injectors (NBI) and the ICRH antenae. (2) Experimental determination of the absolute detection efficiency of the gamma ray spectrometer. This detection efficiency will allow the measured yields of the gamma rays to be converted to a total reaction rate. In addition to these two major accomplishments, we have continued, as permitted by the TFTR operating schedule, the observation of high energy gamma rays from the 3He(D,{gamma})5Li reaction during deuterium NBI heating of 3He plasmas.
Date: February 14, 1992
Creator: Cecil, F.E.

Colorado School of Mines fusion gamma ray diagnostic project. Technical progress report

Description: This report summarizes the 1991 calendar year activities of the fusion gamma ray diagnostics project in the Physics Department at the Colorado School of Mines. Considerable progress has been realized in the fusion gamma ray diagnostic project in the last year. Specifically we have achieved the two major goals of the project as outlined in last year`s proposed work statement to the Office of Applied Plasma Physics in the DOE Division of Magnetic Fusion Energy. The two major goals were: (1) Solution of the severe interference problem encountered during the operation of the gamma ray spectrometer concurrent with high power levels of the neutral beam injectors (NBI) and the ICRH antenae. (2) Experimental determination of the absolute detection efficiency of the gamma ray spectrometer. This detection efficiency will allow the measured yields of the gamma rays to be converted to a total reaction rate. In addition to these two major accomplishments, we have continued, as permitted by the TFTR operating schedule, the observation of high energy gamma rays from the 3He(D,{gamma})5Li reaction during deuterium NBI heating of 3He plasmas.
Date: February 14, 1992
Creator: Cecil, F. E.

Comparison of fracture behavior for low-swelling ferritic and austenitic alloys irradiated in the Fast Flux Test Facility (FFTF) to 180 DPA

Description: Fracture toughness testing was conducted to investigate the radiation embrittlement of high-nickel superalloys, modified austenitic steels and ferritic steels. These materials have been experimentally proven to possess excellent resistance to void swelling after high neutron exposures. In addition to swelling resistance, post-irradiation fracture resistance is another important criterion for reactor material selection. By means of fracture mechanics techniques the fracture behavior of those highly irradiated alloys was characterized in terms of irradiation and test conditions. Precipitation-strengthened alloys failed by channel fracture with very low postirradiation ductility. The fracture toughness of titanium-modified austenitic stainless steel D9 deteriorates with increasing fluence to about 100 displacement per atom (dpa), the fluence level at which brittle fracture appears to occur. Ferritic steels such as HT9 are the most promising candidate materials for fast and fusion reactor applications. The upper-shelf fracture toughness of alloy HT9 remained adequate after irradiation to 180 dpa although its ductile- brittle transition temperature (DBTT) shift by low temperature irradiation rendered the material susceptible to brittle fracture at room temperature. Understanding the fracture characteristics under various irradiation and test conditions helps reduce the potential for brittle fracture by permitting appropriate measure to be taken.
Date: February 1, 1992
Creator: Huang, F.H.