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COMPACTING BIOMASS AND MUNICIPAL SOLID WASTES TO FORM AND UPGRADED FUEL

Description: Biomass waste materials exist in large quantity in every city and in numerous industrial plants such as wood processing plants and waste paper collection centers. Through minimum processing, such waste materials can be turned into a solid fuel for combustion at existing coal-fired power plants. Use of such biomass fuel reduces the amount of coal used, and hence reduces the greenhouse effect and global warming, while at the same time it reduces the use of land for landfill and the associated problems. The carbon-dioxide resulting from burning biomass fuel is recycled through plant growth and hence does not contribute to global warming. Biomass fuel also contains little sulfur and hence does not contribute to acid rain problems. Notwithstanding the environmental desirability of using biomass waste materials, not much of them are used currently due to the need to densify the waste materials and the high cost of conventional methods of densification such as pelletizing and briquetting. The purpose of this project was to test a unique new method of biomass densification developed from recent research in coal log pipeline (CLP). The new method can produce large agglomerates of biomass materials called ''biomass logs'' which are more than 100 times larger and 30% denser than conventional ''pellets'' or ''briquettes''. The Phase I project was to perform extensive laboratory tests and an economic analysis to determine the technical and economic feasibility of the biomass log fuel (BLF). A variety of biomass waste materials, including wood processing residues such as sawdust, mulch and chips of various types of wood, combustibles that are found in municipal solid waste stream such as paper, plastics and textiles, energy crops including willows and switch grass, and yard waste including tree trimmings, fallen leaves, and lawn grass, were tested by using this new compaction technology developed at Capsule ...
Date: November 1, 2000
Creator: Liu, Henry & Li, Yadong
Partner: UNT Libraries Government Documents Department

LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

Description: This project has three main goals: Thin Films Studies, Preparation of Graded Porous Substrates and Basic Electrical Characterization and Testing of Planar Single Cells. During this time period substantial progress has been made in developing low temperature deposition techniques to produce dense, nanocrystalline yttrium-stabilized zirconia films on both dense oxide and polymer substrates. Progress has been made in the preparation and characterization of thin electrolytes and porous LSM substrates. Both of these tasks are essentially on or ahead of schedule. In our proposal, we suggested that the ZrO{sub 2}/Sc system needed to be considered as a candidate as a thin electrolyte. This was because microcrystalline ZrO{sub 2}/Sc has a significantly higher ionic conductivity than YSZ, particularly at the lower temperatures. As a result, some 0.5 micron thick film of ZrO{sub 2}/16% Sc on an alumina substrate (grain size 20nm) was prepared and the electrical conductivity measured as a function of temperature and oxygen activity. The Sc doped ZrO{sub 2} certainly has a higher conductivity that either 20nm or 2400nm YSZ, however, electronic conductivity dominates the conductivity for oxygen activities below 10{sup -15}. Whereas for YSZ, electronic conductivity is not a problem until the oxygen activity decreases below 10{sup -25}. These initial results show that the ionic conductivity of 20nm YSZ and 20nm ZrO{sub 2}/16% Sc are essentially the same and the enhanced conductivity which is observed for Sc doping in microcrystalline specimens is not observed for the same composition when it is nanocrystalline. In addition they show that the electronic conductivity of Sc doped ZrO{sub 2} is at least two orders of magnitude higher than that observed for YSZ. The conclusion one reaches is that for 0.5 to 1 micron thick nanocrystalline films, Sc doping of ZrO{sub 2} has no benefits compared to YSZ. As a result, electrolyte films of ...
Date: March 31, 2000
Creator: Anderson, Harlan U.
Partner: UNT Libraries Government Documents Department

LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

Description: This project has three main goals: Thin Films Studies, Preparation of Graded Porous Substrates and Basic Electrical Characterization and testing of Planar Single Cells. During this time period substantial progress has been made in developing low temperature deposition techniques to produce dense, nanocrystalline yttrium-stabilized zirconia films on both dense oxide and polymer substrates. Microstructural changes in unsupported nanocrystalline yttrium stabilized zirconia (ZrO{sub 2}:16%Y, or YSZ) thin films were examined as a function of temperature and annealing time in order to determine the grain growth exponent and the mechanisms of pinhole formation. Grain growth and pinhole formation were measured using high resolution transmission electron microscopy (HRTEM), normal imaging mode transmission electron microscopy (TEM), electron diffraction, and energy dispersive X-ray microanalysis (EDS). Grain growth was found to vary with a time exponent of about one half before pinhole formation and about one third after. Pinhole formation in 70 nm thick films occurred at temperatures near 600 C, corresponding to a grain size of about 15 nm, or a grain size to film thickness ration of approximately 0.25. The deposition of films on porous substrates is hampered by the penetration of the polymer precursor solution into the substrate whose pores as > 0.2 {micro}m, therefore much attention has to be paid to the development of porous colloidal oxide films onto surfaces. Thus during this line period we have been studying these films. Optical properties have proven to be an excellent way to study the quality of these nanoporous films. The influence of porosity and densification on optical properties of films on sapphire substrates that were prepared from water colloidal suspensions of small ({approx}5nm) particles of ceria was investigated. The colloidal ceria films have initially very porous structure (porosity about 50%) and densification starts at about 600 C accompanied by grain growth. The concurrence ...
Date: September 30, 2000
Creator: Anderson, Harlan U.; Huebner, Wayne & Kosacki, Igor
Partner: UNT Libraries Government Documents Department

LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

Description: This project has three main goals: Thin Films Studies, Preparation of Graded Porous Substrates and Basic Electrical Characterization and testing of Planar Single Cells. Substantial progress has been made on both characterizing thin films as well as developing methods to produce films on nanoporous substrates. The results of electrical conductivity measurements on ZrO{sub 2}:16%Sc nanocrystalline thin films under controlled oxygen partial pressure and temperature are presented. The experimental data have been interpreted using a defect model, which describes the interaction between Sc and oxygen vacancies resulting in the formation of donor - (Sc{sub Zr} - V{sub o} - e){sup x} and acceptor - (Sc{sub Zr}-h){sup x} levels. From this the electronic and ionic contribution to the electrical transport has been determined and correlated with the band structure. These results suggest that ZrO{sub 2}:16%Sc possesses higher electronic conductivity than ZrO{sub 2}:16%Y, which dominates the total conductivity in reducing atmospheres. This is an important result since it indicates that Sc-YSZ maybe useful in the anode regions of the cell. We have made important breakthroughs on depositing dense Ceria films on to porous LSM substrates. In previous studies we have found that in order to produce a surface which is smooth enough to coat with dense polymer precursor derived films, the required thickness of the colloidal film layer is determined by the maximum surface roughness. That is, if we wish to make 2 micron thick colloidal oxide layers, the roughness of the LSM surface can not exceed 2 microns. Currently, we are producing the composite CeO{sub 2}/LSM structures that can be coated with polymer precursor to produce 0.5 to 1.5 micron thickness dense YSZ films. In the next quarter, we will be testing SOFC's using these structures. YSZ/CeO{sub 2}/LSM composites have been formed by annealing at 800 C. Our studies show that the ...
Date: March 31, 2001
Creator: Anderson, Harlan U.; Huebner, Wayne & Kosacki, Igor
Partner: UNT Libraries Government Documents Department

LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

Description: This project has three main goals: Thin Films Studies, Preparation of Graded Porous Substrates and Basic Electrical Characterization and testing of Planar Single Cells. In this portion of study we have focused on producing YSZ films on porous LSM substrates. When using the polymer precursor there are a number of obstacles to overcome in order to form dense electrolyte layers on porous substrates (cathode or anode). Probably the most difficult problems are: (1) Extreme penetration of the polymer into the substrate must be prevented. (2) Shrinkage cracking must be avoided. (3) Film thickness in the 1 to 5{micro}m range must be achieved. We have demonstrated that cracking due to shrinkage involved during the elimination of solvents and organic matter and densification of the remaining oxide is not a problem as long as the resulting oxide film is < {approx} 0.15 {micro}m in thickness. We have also shown that we can make thicker films by making multiple depositions if the substrate is smooth (roughness {le} 0.1 {micro}m) and contains no surface pores > 0.2 {micro}m. The penetration of the polymer into the porous substrate can be minimized by increasing the viscosity of the polymer and reducing the largest pore at the surface of the substrate to {le} 0.2 {micro}m. We have shown that this can be done, but we have also shown that it is difficult to make dense films that are defect free with areas > 1 cm{sup 2}. This is because of the roughness of the substrate and the difficulty in making a substrate which does not have surface voids > 0.2 {micro}m. Thus the process works well for dense, smooth substrates for films < 1 {micro}m thick, but is difficult to apply to rough, porous surfaces and to make film thickness > 1 {micro}m. As a result of ...
Date: September 30, 2001
Creator: Anderson, Harlan U.; Huebner, Wayne & Kosacki, Igor
Partner: UNT Libraries Government Documents Department

LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

Description: This project has three main goals: Thin Films Studies, Preparation of Graded Porous Substrates and Basic Electrical Characterization and testing of Planar Single Cells. This period has continued to address the problem of making dense 1/2 to 5 {micro}m thick dense layers on porous substrates (the cathode LSM). Our current status is that we are making structures of 2-5 cm{sup 2} in area, which consist of either dense YSZ or CGO infiltrated into a 2-5 {micro}m thick 50% porous layer made of either nanoncrystalline CGO or YSZ powder. This composite structure coats a macroporous cathode or anode; which serves as the structural element of the bi-layer structure. These structures are being tested as SOFC elements. A number of structures have been evaluated both as symmetrical and as button cell configuration. Results of this testing indicates that the cathodes contribute the most to cell losses for temperatures below 750 C. In this investigation different cathode materials were studied using impedance spectroscopy of symmetric cells and IV characteristics of anode supported fuel cells. Cathode materials studied included La{sub 0.8}Sr{sub 0.2}Co{sub 0.2}Fe{sub 0.8}O{sub 3} (LSCF), La{sub 0.7}Sr{sub 0.2}MnO{sub 3} (LSM), Pr{sub 0.8}Sr{sub 0.2}Fe{sub 0.8}O{sub 3} (PSCF), Sm{sub 0.8}Sr{sub 0.2}Co{sub 0.2}Fe{sub 0.8}O{sub 3} (SSCF), and Yb{sub .8}Sr{sub 0.2}Co{sub 0.2}Fe{sub 0.8}O{sub 3} (SSCF). A new technique for filtering the Fourier transform of impedance data was used to increase the sensitivity of impedance analysis. By creating a filter specifically for impedance spectroscopy the resolution was increased. The filter was tailored to look for specific circuit elements like R//C, Warburg, or constant phase elements. As many as four peaks can be resolved using the filtering technique on symmetric cells. It may be possible to relate the different peaks to material parameters, like the oxygen exchange coefficient. The cathode grouped in order from lowest to highest ASR is ...
Date: March 31, 2002
Creator: Anderson, Harlan U.; Dogan, Fatih & Petrovsky, Vladimir
Partner: UNT Libraries Government Documents Department

LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

Description: This report represents a summary of the work carried out on this project which started October 1999 and ended March 2003. A list of the publications resulting from the work are contained in Appendix A. The most significant achievements are: (1) Dense nanocrystalline zirconia and ceria films were obtained at temperatures < 400 C. (2) Nanocrystalline films of both ceria and zirconia were characterized. (3) We showed that under anodic conditions 0.5 to 1 micron thick nanocrystalline films of Sc doped zirconia have sufficient electronic conductivity to prevent them from being useful as an electrolyte. (4) We have developed a process by which dense 0.5 to 5 micron thick dense films of either YSZ or ceria can be deposited on sintered porous substrates which serve as either the cathode or anode at temperatures as low as 400 C. (5) The program has provided the research to produce two PhD thesis for students, one is now working in the solid oxide fuel cell field. (6) The results of the research have resulted in 69 papers published, 3 papers submitted or being prepared for publication, 50 oral presentations and 3 patent disclosures.
Date: March 31, 2003
Creator: Anderson, Harlan U.; Dogan, Fatih & Petrovsky, Vladimir
Partner: UNT Libraries Government Documents Department

Refractory for Black Liquor Gasifiers Quarterly Report

Description: The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided ...
Date: July 1, 2004
Creator: Headrick, William L., Jr.; Karakus, Musa; Liang, Xiaoting & Rezaie, Alireza
Partner: UNT Libraries Government Documents Department

Refractory for Black Liquor Gasifiers Quarterly Report

Description: The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. This report covers Task 1.3, ...
Date: March 1, 2005
Creator: Headrick, William L., Jr.; Karakus, Musa & Wei, Jun
Partner: UNT Libraries Government Documents Department

Refractory for Black Liquor Gasifiers Quarterly Report

Description: The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LFHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided ...
Date: December 1, 2003
Creator: Headrick, William L., Jr. & Rezaie, Alireza
Partner: UNT Libraries Government Documents Department

Refractory for Black Liquor Gasifiers Quarterly Report

Description: The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided ...
Date: April 1, 2005
Creator: Jr, William L. Headrick; Karakus, Musa; Liang, Xiaoting & Wei, Jun
Partner: UNT Libraries Government Documents Department

Refractory for Black Liquor Gasifiers Quarterly Report

Description: The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided ...
Date: April 1, 2004
Creator: Headrick, William L., Jr. & Rezaie, Alireza
Partner: UNT Libraries Government Documents Department

Refractory for Black Liquor Gasifiers Quarterly Report

Description: The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided ...
Date: October 1, 2004
Creator: Jr, William L. Headrick; Karakus, Musa; Liang, Xiaoting & Rezaie, Alireza
Partner: UNT Libraries Government Documents Department

Refractory for Black Liquor Gasifiers Quarterly Report

Description: The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided ...
Date: January 1, 2005
Creator: Headrick, William L., Jr.; Karakus, Musa; Liang, Xiaoting & Wei, Jun
Partner: UNT Libraries Government Documents Department

PROCESSING OF LaCrO{sub 3} SOLID OXIDE FUELL CELL APPLICATIONS

Description: In this portion of the research the authors are focusing on the microstructure {leftrightarrow} property relations in solid oxide fuel cells (SOFC's) to better understand the mechanisms involved in cell performance. The overall aim is to fabricate SOFC's with controlled microstructures utilizing La{sub 1-x}Sr{sub x}MnO{sub 3} (LSM), yttria stabilized zirconia (YSZ), and Ni-YSZ composites as the cathode, electrolyte, and anode, respectively. Ideally, the electrode materials would be tailored for an increased reaction rate (grain size {le} 1 {micro}m), be stable with time (> 10,000 h), have a thermal expansion match to YSZ ({alpha} {approx} 11 x 10{sup -6}/C), show limited chemical interaction with the electrolyte, and show no degradation in electrical performance. This paper describes anodic studies, including starting powder characteristics, electrical conductivity and overpotential measurements, and resultant microstructures as a function of processing conditions (i.e. powder calcination temperature, and annealing temperature) and composition. During the last year several important discoveries have been made regarding the influence of composition and microstructure of anodes on the performance of the SOFCs. These results can be summarized as follows: (1) YSZ anodes prepared with lower Ni volume fractions (40 and 45%) resulted in lower overpotentials and improved stability. (2) Higher sintering temperatures effectively lowered the overpotential and increased the in-plane conductivity. Due to constrained sintering between the anode and the YSZ electrolyte, higher sintering temperatures allowed more densification in the z-direction, resulting in a rigid YSZ structure to support Ni particles. (3) By decreasing the densification between Ni grains, there are more paths for conduction (more Ni-Ni contacts throughout the structure and higher conductivities) and a larger number of Ni-YSZ contacts (lower overpotentials). (4) The 45 vol% Ni composition co-fired with the electrolyte had the lowest initial overpotential of any cermet with a similar composition.
Date: November 1, 1999
Creator: Wayne Huebner, Harlan U. Anderson
Partner: UNT Libraries Government Documents Department

TOTAL ORE PROCESSING INTEGRATION AND MANAGEMENT

Description: The lessons learned from ore segregation test No.3 were presented to Minntac Mine personnel during the reporting period. Ore was segregated by A-Factor, with low values going to Step 1/2 and high values going to Step 3. During the test, the mine maintained the best split possible for the given production and location constraints. During the test, Step 1&2 A-Factor was lowered more than Step 3 was raised. All other ore quality changes were not manipulated, but the segregation by A-Factor affected most of the other qualities. Magnetic iron, coarse tails, fine tails, silica, and grind changed in response to the split. Segregation was achieved by adding ore from HIS to the Step 3 blend and lowering the amount of LC 1&2 and somewhat lowering the amount of LC 3&4. Conversely, Step 1&2 received less HIS with a corresponding increase in LC 1&2. The amount of IBC was increased to both Steps about one-third of the way into the test. For about the center half of the test, LC 3&4 was reduced to both Steps. The most noticeable layer changes were, then: an increase in the HIS split; a decrease in the LC 1&2 split; adding IBC to both Steps; and lowering LC 3&4 to both Steps. Statistical analysis of the dataset collected during ordinary, non-segregated operation of the mine and mill is continuing. Graphical analysis of blast patterns according to drill monitor data was slowed by student classwork. It is expected to resume after the semester ends in May.
Date: May 16, 2005
Creator: Gertsch, Leslie & Gertsch, Richard
Partner: UNT Libraries Government Documents Department

TOTAL ORE PROCESSING INTEGRATION AND MANAGEMENT

Description: A new dataset to illustrate ordinary, non-segregated operation of the mine and mill has been collected. Beginning in mid-November, it ended on 31 December, 2004. Drill monitoring data for several blast patterns is being analyzed. Figures 1 through 6 represent one of the patterns. Sample preparation for laboratory rock strength tests is underway, for comparison with the density and point-load test results measured last summer. The relationships among data mined from the databases and the ore segregation tests of both mines are being examined, mainly through use of multiple regression analysis. The study is ongoing.
Date: May 16, 2005
Creator: Gertsch, Leslie & Gertsch, Richard
Partner: UNT Libraries Government Documents Department

DEVELOPMENT PRACTICES FOR OPTIMIZED MEOR IN SHALLOW HEAVY OIL RESERVOIRS

Description: The objective of this research project is to demonstrate an economically viable and sustainable method of producing shallow heavy oil reserves in western Missouri and southeastern Kansas, using an integrated approach including surface geochemical surveys, conventional MEOR treatments, horizontal fracturing in vertical wells, electrical resistivity tomography (ERT), and reservoir simulation to optimize the recovery process. The objective also includes transferring the knowledge gained from the project to other local landowners, to demonstrate how they may identify and develop their own heavy oil resources with little capital investment. The first year period was divided into two phases--Phase I and Phase II. Each phase was 6 months in duration. Tasks completed in first six month period included soil sampling, geochemical analysis, construction of ERT arrays, collection of background ERT surveys, and analysis of core samples to develop a geomechanical model for designing the hydraulic fracturing treatment. Five wells were to be drilled in phase I. However, weather and funding delays resulted in drilling shifting to the second phase of the project. During the second six month period, five vertical wells were drilled through the Bluejacket and Warner Sands. These wells were drilled with air and logged openhole. Drilling locations were selected after reviewing results of background ERT and geochemical surveys. Three ERT wells (2,3,4) were arranged in an equilateral triangle, spaced 70 feet apart and these wells were completed open hole. ERT arrays constructed during Phase I, were installed and background surveys were taken. Two wells (1,5) were drilled, cased, cemented and perforated. These wells were located north and south of the three ERT wells. Each well was stimulated with a linear guar gel and 20/40 mesh Brady sand. Tiltmeters were used with one fracture treatment to verify fracture morphology. Work performed during the first year of this research project demonstrates that ...
Date: March 1, 2004
Creator: Dunn-Norman, Shari
Partner: UNT Libraries Government Documents Department

DEVELOPMENT PRACTICES FOR OPTIMIZED MEOR IN SHALLOW HEAVY OIL RESERVOIRS

Description: The objective of this research project is to demonstrate an economically viable and sustainable method of producing shallow heavy oil reserves in western Missouri and southeastern Kansas, using an integrated approach including surface geochemical surveys, conventional MEOR treatments, horizontal fracturing in vertical wells, electrical resistivity tomography (ERT), and reservoir simulation to optimize the recovery process. The objective also includes transferring the knowledge gained from the project to other local landowners, to demonstrate how they may identify and develop their own heavy oil resources with minimal capital investment. Tasks completed in the first six-month period include soil sampling, geochemical analysis, construction of ERT arrays, collection of background ERT surveys, and analysis of core samples to develop a geomechanical model for designing the hydraulic fracturing treatment. Five wells were to be drilled in phase I. However, weather and funding delays resulted in drilling shifting to the second phase of the project. Work performed to date demonstrates that surface geochemical methods can be used to differentiate between productive and non-productive areas of the Warner Sand and that ERT can be used to successfully image through the Warner Sand.
Date: September 5, 2003
Creator: Dunn-Norman, Shari
Partner: UNT Libraries Government Documents Department

DEVELOPMENT PRACTICES FOR OPTIMIZED MEOR IN SHALLOW HEAVY OIL RESERVOIRS

Description: The objective of this research project is to demonstrate an economically viable and sustainable method of producing shallow heavy oil reserves in western Missouri and southeastern Kansas, using an integrated approach including surface geochemical surveys, conventional MEOR treatments, horizontal fracturing in vertical wells, electrical resistivity tomography (ERT), and reservoir simulation to optimize the recovery process. The objective also includes transferring the knowledge gained from the project to other local landowners, to demonstrate how they may identify and develop their own heavy oil resources with minimal capital investment. In the twelve to eighteen-month project period, three wells were equipped with ERT arrays. Electrical resistivity tomography (ERT) background measurements were taken in the three ERT equipped wells. Pumping equipment was installed on the two fracture stimulated wells and pumping tests were conducted following the hydraulic fracture treatments. All wells were treated monthly with microbes, by adding a commercially available microbial mixture to wellbore fluids. ERT surveys were taken on a monthly basis, following microbial treatments. Worked performed to date demonstrates that resistivity changes are occurring in the subsurface, with resistivity increasing slightly. Pumping results for the hydraulically fractured wells were disappointing, with only a show of oil recovered and an increase in well shut-in pressure.
Date: June 1, 2005
Creator: Dunn-Norman, Shari
Partner: UNT Libraries Government Documents Department

Characterization of Tumor-Avid Antibody Fragments Genetically Engineered for Mono-Specific Radionuclide Chelation

Description: The successful clinical application of targeted-radiopharmaceuticals depends on the development of molecules that optimize tumor specific radionuclide deposition and minimize non-specific organ irradiation. To this end, this proposal outlines a research effort to identify and evaluate novel antibodies and antibody fragments that bind breast tumors. The tumor-avid antibodies will be investigated for as imaging and therapeutic agents and to gain a better understanding of the pharmacokinetics and metabolism of radiolabeled tumor-avid antibody fragments through the use of site-specifically labeled molecules. Antibodies or antibody fragments, that bind breast carcinoma carbohydrate antigens, will be obtained from hybridoma or bacteriophage library screening. More specifically, antibody fragments that bind the carcinoma-associated Thomsen-Friedenreich (T) antigen will be radiolabeled with {sup 99m}Tc and {sup 188}Re at a natural amino acid chelation site and will be investigated in vivo for their abilities to target human breast tumors. In addition, site-specific radiolabeled antibody fragments will be biosynthesized using misacylated suppressor tRNAs. Homogeneously radiolabeled populations of antibody fragments will be used to investigate the effects of radionuclide location and chelation chemistries on their biodistribution and metabolism. It is hypothesized that site-specifically radiolabeled antibody fragments will possess enhanced tumor imaging and therapeutic properties due to optimal label location and conjugation chemistries. New insights into the factors that govern antibody metabolism in vivo are also expected from this work. Results from these studies should enhance our ability to design and synthesize radiolabeled antibody fragments that have improved pharmacokinetic properties. The studies in this proposal involve basic research into the development of antibody-based radiopharmaceuticals, with the ultimate goal of application in humans. This type of basic nuclear medicine research has been funded by the Department of Energy and is consistent with the research topics and guidelines recommended during the recent review of the Medical Applications and Biophysical Research Program.
Date: December 31, 2003
Creator: Quinn, T.P.
Partner: UNT Libraries Government Documents Department