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Post-Closure Monitoring Report for Corrective Action Unit 329: Area 22 Desert Rock Airstrip Fuel Spill, Nevada Test Site, Nevada (Rev. No.: 0, June 2002)

Description: There was an increase in total petroleum hydrocarbons (TPH) concentrations at all three depths within Borehole DRA-0. The oxygen concentration at 40 ft below ground surface (bgs) decreased. There was also an increase in carbon dioxide concentration at that depth. The decrease in oxygen concentrations and the increase in carbon dioxide concentration at the 40 ft bgs level could be possible indicators of natural attenuation. It is not possible to determine trends or biodegradation rates with the limited amount of data collected from the site. The sample results from this first monitoring period did not correlate with the baseline results collected in August 2000. Additional samples will be collected and the results will be compared to previously collected samples to determine if the site was at equilibrium in August 2000. Continued annual monitoring will be conducted as specified in the Closure Report to determine trends at the site. As natural attenuation occurs, the TPH concentrations should decrease. The TPH concentrations will be compared over successive monitoring events to determine trends and approximate rates. As natural attenuation occurs, oxygen will be consumed and carbon dioxide will be produced. The oxygen, nitrogen, and carbon dioxide concentrations will also be evaluated to determine if biodegradation is indicated. When all available oxygen has been consumed, methane-producing bacteria may continue the natural attenuation process so methane levels will be monitored as an additional possible indicator of natural attenuation. The rate of decrease will be determined on the microbial populations, contaminant concentrations, available nutrients, and other environmental factors. Samples were collected and submitted for microbial analysis during closure activities. The results indicated that the microbial populations and nutrients were adequate for limited bioremediation (DOE/NV, 2000). Additional sampling for microbial analysis are not planned. The site is currently inactive and the source of additional contamination was removed. ...
Date: June 6, 2002
Creator: /NV, NNSA
Partner: UNT Libraries Government Documents Department

Arctic Energy Technology Development Laboratory (Part 2)

Description: Methane (CH{sub 4}) in natural gas is a major energy source in the U.S., and is used extensively on Alaska's North Slope, including the oilfields in Prudhoe Bay, the community of Barrow, and the National Petroleum Reserve, Alaska (NPRA). Smaller villages, however, are dependent on imported diesel fuel for both power and heating, resulting in some of the highest energy costs in the U.S. and crippling local economies. Numerous CH{sub 4} gas seeps have been observed on wetlands near Atqasuk, Alaska (in the NPRA), and initial measurements have indicated flow rates of 3,000-5,000 ft{sup 3} day{sup -1} (60-100 kg CH{sub 4} day{sup -1}). Gas samples collected in 1996 indicated biogenic origin, although more recent sampling indicated a mixture of biogenic and thermogenic gas. In this study, we (1) quantified the amount of CH{sub 4} generated by several seeps and evaluated their potential use as an unconventional gas source for the village of Atqasuk; (2) collected gas and analyzed its composition from multiple seeps several miles apart to see if the source is the same, or if gas is being generated locally from isolated biogenic sources; and (3) assessed the potential magnitude of natural CH{sub 4} gas seeps for future use in climate change modeling.
Date: December 31, 2008
Creator: 960443, See OSTI ID Number
Partner: UNT Libraries Government Documents Department

A Novel High-Heat Transfer Low-NO{sub x} Natural Gas Combustion System. Final Technical Report

Description: A novel high-heat transfer low NO(sub x) natural gas combustion system. The objectives of this program are to research, develop, test, and commercialize a novel high-heat transfer low-NO{sub x} natural gas combustion system for oxygen-, oxygen-enriched air, and air-fired furnaces. This technology will improve the process efficiency (productivity and product quality) and the energy efficiency of high-temperature industrial furnaces by at least 20%. GTI's high-heat transfer burner has applications in high-temperature air, oxygen-enriched air, and oxygen furnaces used in the glass, metals, cement, and other industries. Development work in this program is focused on using this burner to improve the energy efficiency and productivity of glass melting furnaces that are major industrial energy consumers. The following specific project objectives are defined to provide a means of achieving the overall project objectives. (1) Identify topics to be covered, problems requiring attention, equipment to be used in the program, and test plans to be followed in Phase II and Phase III. (2) Use existing codes to develop models of gas combustion and soot nucleation and growth as well as a thermodynamic and parametric description of furnace heat transfer issues. (3) Conduct a parametric study to confirm the increase in process and energy efficiency. (4) Design and fabricate a high-heat transfer low-NOx natural gas burners for laboratory, pilot- and demonstration-scale tests. (5) Test the high-heat transfer burner in one of GTI's laboratory-scale high-temperature furnaces. (6) Design and demonstrate the high-heat transfer burner on GTI's unique pilot-scale glass tank simulator. (7) Complete one long term demonstration test of this burner technology on an Owens Corning full-scale industrial glass melting furnace. (8) Prepare an Industrial Adoption Plan. This Plan will be updated in each program Phase as additional information becomes available. The Plan will include technical and economic analyses, energy savings and waste reduction predictions, ...
Date: January 1, 2004
Creator: Abbasi, H.
Partner: UNT Libraries Government Documents Department

Evaluation of Ultra Clean Fuels from Natural Gas

Description: ConocoPhillips, in conjunction with Nexant Inc., Penn State University, and Cummins Engine Co., joined with the U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) in a cooperative agreement to perform a comprehensive study of new ultra clean fuels (UCFs) produced from remote sources of natural gas. The project study consists of three primary tasks: an environmental Life Cycle Assessment (LCA), a Market Study, and a series of Engine Tests to evaluate the potential markets for Ultra Clean Fuels. The overall objective of DOE's Ultra Clean Transportation Fuels Initiative is to develop and deploy technologies that will produce ultra-clean burning transportation fuels for the 21st century from both petroleum and non-petroleum resources. These fuels will: (1) Enable vehicles to comply with future emission requirements; (2) Be compatible with the existing liquid fuels infrastructure; (3) Enable vehicle efficiencies to be significantly increased, with concomitantly reduced CO{sub 2} emissions; (4) Be obtainable from a fossil resource, alone or in combination with other hydrocarbon materials such as refinery wastes, municipal wastes, biomass, and coal; and (5) Be competitive with current petroleum fuels. The objectives of the ConocoPhillips Ultra Clean Fuels Project are to perform a comprehensive life cycle analysis and to conduct a market study on ultra clean fuels of commercial interest produced from natural gas, and, in addition, perform engine tests for Fisher-Tropsch diesel and methanol in neat, blended or special formulations to obtain data on emissions. This resulting data will be used to optimize fuel compositions and engine operation in order to minimize the release of atmospheric pollutants resulting from the fuel combustion. Development and testing of both direct and indirect methanol fuel cells was to be conducted and the optimum properties of a suitable fuel-grade methanol was to be defined. The results of the study are also applicable to ...
Date: February 28, 2006
Creator: Abbott, Robert; Casey, Edward; Esen, Etop; Smith, Douglas; Burke, Bruce; Nguyen, Binh et al.
Partner: UNT Libraries Government Documents Department

Compression ratio effect on methane HCCI combustion

Description: We have used the HCT (Hydrodynamics, Chemistry and Transport) chemical kinetics code to simulate HCCI (homogeneous charge compression ignition) combustion of methane-air mixtures. HCT is applied to explore the ignition timing, bum duration, NO<sub>x</sub> production, gross indicated efficiency and gross IMEP of a supercharged engine (3 atm. Intake pressure) with 14:1, 16:l and 18:1 compression ratios at 1200 rpm. HCT has been modified to incorporate the effect of heat transfer and to calculate the temperature that results from mixing the recycled exhaust with the fresh mixture. This study uses a single control volume reaction zone that varies as a function of crank angle. The ignition process is controlled by adjusting the intake equivalence ratio and the residual gas trapping (RGT). RGT is internal exhaust gas recirculation which recycles both thermal energy and combustion product species. Adjustment of equivalence ratio and RGT is accomplished by varying the timing of the exhaust valve closure in either 2-stroke or 4-stroke engines. Inlet manifold temperature is held constant at 300 K. Results show that, for each compression ratio, there is a range of operational conditions that show promise of achieving the control necessary to vary power output while keeping indicated efficiency above 50% and NO<sub>x</sub> levels below 100 ppm. HCT results are also compared with a set of recent experimental data for natural gas.
Date: September 29, 1998
Creator: Aceves, S. M.; Pitz, W.; Smith, J. R. & Westbrook, C.
Partner: UNT Libraries Government Documents Department

Sensitivity of natural gas HCCI combustion to fuel and operating parameters using detailed kinetic modeling

Description: This paper uses the HCT (Hydrodynamics, Chemistry and Transport) chemical kinetics code to analyze natural gas HCCI combustion in an engine. The HCT code has been modified to better represent the conditions existing inside an engine, including a wall heat transfer correlation. Combustion control and low power output per displacement remain as two of the biggest challenges to obtaining satisfactory performance out of an HCCI engine, and these are addressed in this paper. The paper considers the effect of natural gas composition on HCCI combustion, and then explores three control strategies for HCCI engines: DME (dimethyl ether) addition, intake heating and hot EGR addition. The results show that HCCI combustion is sensitive to natural gas composition, and an active control may be required to compensate for possible changes in composition. The three control strategies being considered have a significant effect in changing the combustion parameters for the engine, and should be able to control HCCI combustion.
Date: July 19, 1999
Creator: Aceves, S.; Dibble, R.; Flowers, D.; Smith, J. R. & Westbrook, C. K.
Partner: UNT Libraries Government Documents Department

Optimization of a CNG series hybrid concept vehicle

Description: Compressed Natural Gas (CNG) has favorable characteristics as a vehicular fuel, in terms of fuel economy as well as emissions. Using CNG as a fuel in a series hybrid vehicle has the potential of resulting in very high fuel economy (between 26 and 30 km/liter, 60 to 70 mpg) and very low emissions (substantially lower than Federal Tier II or CARB ULEV). This paper uses a vehicle evaluation code and an optimizer to find a set of vehicle parameters that result in optimum vehicle fuel economy. The vehicle evaluation code used in this analysis estimates vehicle power performance, including engine efficiency and power, generator efficiency, energy storage device efficiency and state-of-charge, and motor and transmission efficiencies. Eight vehicle parameters are selected as free variables for the optimization. The optimum vehicle must also meet two perfect requirements: accelerate to 97 km/h in less than 10 s, and climb an infinitely long hill with a 6% slope at 97 km/h with a 272 kg (600 lb.) payload. The optimizer used in this work was originally developed in the magnetic fusion energy program, and has been used to optimize complex systems, such as magnetic and inertial fusion devices, neutron sources, and mil guns. The optimizer consists of two parts: an optimization package for minimizing non-linear functions of many variables subject to several non-linear equality and/or inequality constraints and a programmable shell that allows interactive configuration and execution of the optimizer. The results of the analysis indicate that the CNG series hybrid vehicle has a high efficiency and low emissions. These results emphasize the advantages of CNG as a near-term alternative fuel for vehicles.
Date: September 22, 1995
Creator: Aceves, S.M.; Smith, J.R.; Perkins, L.J.; Haney, S.W. & Flowers, D.L.
Partner: UNT Libraries Government Documents Department

Compressed Natural Gas (CNG) Transit Bus Experience Survey: April 2009--April 2010

Description: This survey was commissioned by the U.S. Department of Energy (DOE) and the National Renewable Energy Laboratory (NREL) to collect and analyze experiential data and information from a cross-section of U.S. transit agencies with varying degrees of compressed natural gas (CNG) bus and station experience. This information will be used to assist DOE and NREL in determining areas of success and areas where further technical or other assistance might be required, and to assist them in focusing on areas judged by the CNG transit community as priority items.
Date: September 1, 2010
Creator: Adams, R. & Horne, D. B.
Partner: UNT Libraries Government Documents Department

Outlook and Challenges for Chinese Coal

Description: China has been, is, and will continue to be a coal-powered economy. The rapid growth of coal demand since 2001 has created deepening strains and bottlenecks that raise questions about supply security. Although China's coal is 'plentiful,' published academic and policy analyses indicate that peak production will likely occur between 2016 and 2029. Given the current economic growth trajectory, domestic production constraints will lead to a coal gap that is not likely to be filled with imports. Urbanization, heavy industry growth, and increasing per-capita consumption are the primary drivers of rising coal usage. In 2006, the power sector, iron and steel, and cement accounted for 71% of coal consumption. Power generation is becoming more efficient, but even extensive roll-out of the highest efficiency units could save only 14% of projected 2025 coal demand. If China follows Japan, steel production would peak by 2015; cement is likely to follow a similar trajectory. A fourth wedge of future coal consumption is likely to come from the burgeoning coal-liquefaction and chemicals industries. New demand from coal-to-liquids and coal-to-chemicals may add 450 million tonnes of coal demand by 2025. Efficient growth among these drivers indicates that China's annual coal demand will reach 4.2 to 4.7 billion tonnes by 2025. Central government support for nuclear and renewable energy has not been able to reduce China's growing dependence on coal for primary energy. Few substitution options exist: offsetting one year of recent coal demand growth would require over 107 billion cubic meters of natural gas, 48 GW of nuclear, or 86 GW of hydropower capacity. While these alternatives will continue to grow, the scale of development using existing technologies will be insufficient to substitute significant coal demand before 2025. The central role of heavy industry in GDP growth and the difficulty of substituting other fuels suggest ...
Date: June 20, 2008
Creator: Aden, Nathaniel T.; Fridley, David G. & Zheng, Nina
Partner: UNT Libraries Government Documents Department

Attrition Resistant Iron-Based Catalysts For F-T SBCRs

Description: The Fischer-Tropsch (F-T) reaction provides a way of converting coal-derived synthesis gas (CO+ H{sub 2}) to liquid fuels. Since the reaction is highly exothermic, one of the major problems in control of the reaction is heat removal. Recent work has shown that the use of slurry bubble column reactors (SBCRs) can largely solve this problem. The use of iron-(FE) based catalysts is attractive not only due to their low cost and ready availability, but also due to their high water-gas shift activity which makes it possible to use these catalysts with low H{sub 2}/CO ratios. However, a serious problem with the use of Fe catalysts in a SBCR is their tendency to undergo attrition. This can cause fouling/plugging of downstream filters and equipment; makes the separation of catalyst from the oil/wax product very difficult, if not impossible; and results in a steady loss of catalyst from the reactor. Under a previous Department of Energy (DOE)/University Research Grant (UCR) grant, Hampton University reported, for the first time, the development of demonstrably attrition-resistant Fe F-T synthesis catalysts having good activity, selectivity, and attrition resistance. These catalysts were prepared by spray drying Fe catalysts with potassium (K), copper (Cu), and silica (SiO{sub 2}) as promoters. SiO{sub 2} was also used as a binder for spray drying. These catalysts were tested for activity and selectivity in a laboratory-scale fixed-bed reactor. Fundamental understanding of attrition is being addressed by incorporating suitable binders into the catalyst recipe. This has resulted in the preparation of a spray dried HPR-43 catalyst having average particle size (aps) of 70 {micro}m with high attrition resistance. This HPR-43 attrition resistant, active and selective catalyst gave 95% CO conversion through 125 hours of testing in a fixed-bed at 270 C, 1.48 MPa, H{sub 2}/CO=0.67 and 2.0 NL/g-cat/h with C{sub 5+} selectivity of ...
Date: January 31, 2006
Creator: Adeyiga, Adeyinka A.
Partner: UNT Libraries Government Documents Department

DEVELOPMENT OF ATTRITION RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS

Description: The Fischer-Tropsch (F-T) reaction provides a way of converting coal-derived synthesis gas (CO+H{sub 2}) to liquid fuels. Since the reaction is highly exothermic, one of the major problems in control of the reaction is heat removal. Recent work has shown that the use of slurry bubble column reactors (SBCRs) can largely solve this problem. The use of iron-based catalysts is attractive not only due to their low cost and ready availability, but also due to their high water-gas shift activity which makes it possible to use these catalysts with low H{sub 2}/CO ratios. However, a serious problem with use of Fe catalysts in a SBCR is their tendency to undergo attrition. This can cause fouling/plugging of downstream filters and equipment, makes the separation of catalyst from the oil/wax product very difficult if not impossible, and results in a steady loss of catalyst from the reactor. Recently, fundamental understanding of physical attrition is being addressed by incorporating suitable binders into the catalyst recipe. This has resulted in the preparation of a spray dried Fe-based catalyst having aps of 70 mm with high attrition resistance. This Fe-based attrition resistant, active and selective catalyst gave 95% CO conversion through 125 hours of testing in a fixed-bed at 270 C, 1.48 MPa, H{sub 2}/CO=0.67 and 2.0 NL/g-cat/h with C{sub 5}{sup +} selectivity of &gt;78% and methane selectivity of &lt;5%. However, further development of the catalyst is needed to address the chemical attrition due to phase changes that any Fe-catalyst goes through potentially causing internal stresses within the particle and resulting in weakening, spalling or cracking. The objective of this research is to develop robust iron-based Fischer-Tropsch catalysts that have suitable activity, selectivity and stability to be used in the slurry bubble column reactor. Specifically we aim to develop to: (i) improve the performance and ...
Date: September 1, 2001
Creator: Adeyiga, Adeyinka A.
Partner: UNT Libraries Government Documents Department

DEVELOPMENT OF ATTRITION RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS

Description: Fischer-Tropsch (FT) synthesis to convert syngas (CO + H{sub 2}) derived from natural gas or coal to liquid fuels and wax is a well-established technology. For low H{sub 2} to CO ratio syngas produced from CO{sub 2} reforming of natural gas or from gasification of coal, the use of Fe catalysts is attractive because of their high water gas shift activity in addition to their high FT activity. Fe catalysts are also attractive due to their low cost and low methane selectivity. Because of the highly exothermic nature of the FT reaction, there has been a recent move away from fixed-bed reactors toward the development of slurry bubble column reactors (SBCRs) that employ 30 to 90 {micro}m catalyst particles suspended in a waxy liquid for efficient heat removal. However, the use of Fe FT catalysts in an SBCR has been problematic due to severe catalyst attrition resulting in fines that plug the filter employed to separate the catalyst from the waxy product. Fe catalysts can undergo attrition in SBCRs not only due to vigorous movement and collisions but also due to phase changes that occur during activation and reaction. The objectives of this research were to develop a better understanding of the parameters affecting attrition of Fe F-T catalysts suitable for use in SBCRs and to incorporate this understanding into the design of novel Fe catalysts having superior attrition resistance. The catalysts were prepared by co-precipitation, followed by binder addition and spray drying at 250 C in a 1 m diameter, 2 m tall spray dryer. The binder silica content was varied from 0 to 20 wt %. The results show that use of small amounts of precipitated SiO{sub 2} alone in spray-dried Fe catalysts can result in good attrition resistance. All catalysts investigated with SiO{sub 2} wt% {le} 12 ...
Date: December 1, 2003
Creator: Adeyiga, Adeyinka A.
Partner: UNT Libraries Government Documents Department

DIGESTER GAS - FUEL CELL - PROJECT

Description: GEW has been operating the first fuel cell in Europe producing heat and electricity from digester gas in an environmentally friendly way. The first 9,000 hours in operation were successfully concluded in August 2001. The fuel cell powered by digester gas was one of the 25 registered ''Worldwide projects'' which NRW presented at the EXPO 2000. In addition to this, it is a key project of the NRW State Initiative on Future Energies. All of the activities planned for the first year of operation were successfully completed: installing and putting the plant into operation, the transition to permanent operation as well as extended monitoring till May 2001.
Date: March 1, 2002
Creator: Adolph, Dr.-Eng. Dirk & Saure, Dipl.-Eng. Thomas
Partner: UNT Libraries Government Documents Department

IMPROVED TUBULARS FOR BETTER ECONOMICS IN DEEP GAS WELL DRILLING USING MICROWAVE TECHNOLOGY

Description: The main objective of the research program has been to improve the rate-of-penetration in deep hostile environments by improving the life cycle and performance of coiled-tubing, an important component of a deep well drilling system for oil and gas exploration, by utilizing the latest developments in the microwave materials technology. This is being accomplished by developing an efficient and economically viable continuous microwave process to sinter continuously formed/extruded steel powder for the manufacture of seamless coiled tubing and other tubular products. The entire program has been spread over three phases with the following goals: Phase I--Demonstration of the feasibility concept of continuous microwave sintering process for tubular steel products. Phase II--Design, building and testing of a prototype microwave system which shall be combined with a continuous extruder for steel tubular objects. Phase III--Execution of the plan for commercialization of the technology by one of the industrial partners. The criteria for the success of the program is based on the performance of coiled tubing made by the microwave process. It is expected that this product will have superior quality and performance to the standard product, and will be economically viable.
Date: January 1, 2004
Creator: Agrawal, Dinesh
Partner: UNT Libraries Government Documents Department

Improved Tubulars for Better Economics in Deep Gas Well Drilling Using Microwave Technology

Description: The main objective of the entire research program has been to improve the rate-of-penetration in deep hostile environments by improving the life cycle and performance of coiled-tubing, an important component of a deep well drilling system for oil and gas exploration, by utilizing the latest developments in the microwave materials technology. Based on the results of the Phase I and insurmountable difficulties faced in the extrusion and de-waxing processes, the approach of achieving the goals of the program was slightly changed in the Phase II in which an approach of microwave sintering combined with Cold Isostatic Press (CIP) and joining (by induction or microwave) has been adopted. This process can be developed into a semicontinuous sintering process if the CIP can produce parts fast enough to match the microwave sintering rates. The main objective of the Phase II research program is to demonstrate the potential to economically manufacture microwave processed coiled tubing with improved performance for extended useful life under hostile coiled tubing drilling conditions. After the completion of the Phase II, it is concluded that scale up and sintering of a thin wall common O.D. size tubing that is widely used in the market is still to be proved and further experimentation and refinement of the sintering process is needed in Phase III. Actual manufacturing capability of microwave sintered, industrial quality, full length tubing will most likely require several million dollars of investment.
Date: September 30, 2006
Creator: Agrawal, Dinesh
Partner: UNT Libraries Government Documents Department

DEVELOPMENT OF ADVANCED DRILL COMPONENTS FOR BHA USING MICROWAVE TECHNOLOGY INCORPORATING CARBIDE, DIAMOND COMPOSITES AND FUNCTIONALLY GRADED MATERIALS

Description: The main objective of this program was to develop an efficient and economically viable microwave processing technique to process cobalt cemented tungsten carbide with improved properties for drill-bits for advanced drilling operations for oil, gas, geothermal and excavation industries. The program was completed in three years and successfully accomplished all the states goals in the original proposal. In three years of the program, we designed and built several laboratory scale microwave sintering systems for conducting experiments on Tungsten carbide (WC) based composites in controlled atmosphere. The processing conditions were optimized and various properties were measured. The design of the system was then modified to enable it to process large commercial parts of WC/Co and in large quantities. Two high power (3-6 kW) microwave systems of 2.45 GHz were built for multi samples runs in a batch process. Once the process was optimized for best results, the technology was successfully transferred to our industrial partner, Dennis Tool Co. We helped them to built couple of prototype microwave sintering systems for carbide tool manufacturing. It was found that the microwave processed WC/Co tools are not only cost effective but also exhibited much better overall performance than the standard tools. The results of the field tests performed by Dennis Tool Co. showed remarkable advantage and improvement in their overall performance. For example: wear test shows an increase of 20-30%, corrosion test showed much higher resistance to the acid attack, erosion test exhibited about 15% better resistance than standard sinter-HIP parts. This proves the success of microwave technology for WC/Co based drilling tools. While we have successfully transferred the technology to our industrial partner Dennis Tool Co., they have signed an agreement with Valenite, a world leading WC producer of cutting and drilling tools and wear parts, to push aggressively the new microwave technology ...
Date: November 1, 2000
Creator: Agrawal, Dinesh & Roy, Rustum
Partner: UNT Libraries Government Documents Department

Improved Tubulars for Better Economics in Deep Gas Well Drilling using Microwave Technology

Description: The objective of the research program has been to improve the rate-of-penetration in deep hostile environments by improving the life cycle and performance of coiled-tubing, an important component of a deep well drilling system for oil and gas exploration. The current process of the manufacture long tubular steel products consists of shaping the tube from flat strip, welding the seam and sections into lengths that can be miles long, and coiling onto reels. However, the welds, that are a weak point, now limit the performance of the coil tubing. This is not only from a toughness standpoint but also from a corrosion standpoint. By utilizing the latest developments in the sintering of materials with microwave energy and powder metal extrusion technology for the manufacture of seamless coiled tubing and other tubular products, these problems can be eliminated. The project is therefore to develop a continuous microwave process to sinter continuously steel tubulars and butt-join them using microwave/induction process. The program started about three years ago and now we are in the middle of Phase II. In Phase I (which ended in February 2005) a feasibility study of the extrusion process of steel powder and continuously sinter the extruded tubing was conducted. The research program has been based on the development of microwave technology to process tubular specimens of powder metals, especially steels. The existing microwave systems at the Materials Research Laboratory (MRL) and Dennis Tool Company (DTC) were suitably modified to process tubular small specimens. The precursor powder metals were either extruded or cold isostatically pressed (CIP) to form tubular specimens. After conducting an extensive and systematic investigation of extrusion process for producing long tubes, it was determined that there were several difficulties in adopting extrusion process and it cannot be economically used for producing thousands of feet long green ...
Date: February 1, 2006
Creator: Agrawal, Dinesh; Gigl, Paul & Dennis, Mahlon
Partner: UNT Libraries Government Documents Department

IMPROVED TUBULARS FOR BETTER ECONOMICS IN DEEP GAS WELL DRILLING USING MICROWAVE TECHNOLOGY

Description: The main objective of the research program has been to improve the rate-of-penetration in deep hostile environments by improving the life cycle and performance of coiled-tubing, an important component of a deep well drilling system for oil and gas exploration, by utilizing the latest developments in the microwave materials technology. Originally, it was proposed to accomplish this by developing an efficient and economically viable continuous microwave process to sinter continuously formed/extruded steel powder for the manufacture of seamless coiled tubing and other tubular products. However, based on the results and faced with insurmountable difficulties in the extrusion and de-waxing processes, the approach of achieving the goals of the program has been slightly changed. In the continuation proposal an approach of microwave sintering combined with Cold Isostatic Press (CIP) and joining (by induction or microwave) is adopted. This process can be developed into a semi-continuous sintering process if the CIP can produce parts fast enough to match the microwave sintering rates. Originally, the entire program was spread over three phases with the following goals: Phase I: Demonstration of the feasibility concept of continuous microwave sintering process for tubular steel products. Phase II: Design, building and testing of a prototype microwave system which shall be combined with a continuous extruder for steel tubular objects. Phase III: Execution of the plan for commercialization of the technology by one of the industrial partners. However, since some of the goals of the phase I were not completed, an extension of nine months was granted and we continued extrusion experiments, designed and built semicontinuous microwave sintering unit.
Date: March 1, 2005
Creator: Agrawal, Dinesh; Gigl, Paul; Dennis, Mahlon & Stanley, Roderic
Partner: UNT Libraries Government Documents Department

Improved Tubulars for Better Economics in Deep Gas Well Drilling using Microwave Technology

Description: The main objective of the entire research program has been to improve the rate-of-penetration in deep hostile environments by improving the life cycle and performance of coiled-tubing, an important component of a deep well drilling system for oil and gas exploration, by utilizing the latest developments in the microwave materials technology. Based on the results of the Phase I and insurmountable difficulties faced in the extrusion and de-waxing processes, the approach of achieving the goals of the program was slightly changed in the Phase II in which an approach of microwave sintering combined with Cold Isostatic Press (CIP) and joining (by induction or microwave) has been adopted. This process can be developed into a semicontinuous sintering process if the CIP can produce parts fast enough to match the microwave sintering rates. The main objective of the Phase II research program is to demonstrate the potential to economically manufacture microwave processed coiled tubing with improved performance for extended useful life under hostile coiled tubing drilling conditions. After the completion of the Phase II, it is concluded that scale up and sintering of a thin wall common O.D. size tubing that is widely used in the market is still to be proved and further experimentation and refinement of the sintering process is needed in Phase III. Actual manufacturing capability of microwave sintered, industrial quality, full length tubing will most likely require several million dollars of investment.
Date: July 31, 2007
Creator: Agrawal, Dinesh; Gigl, Paul; Hunt, Mark & Dennis, Mahlon
Partner: UNT Libraries Government Documents Department

Fundamentals of Natural Gas and Species Flows from Hydrate Dissociation - Applications to Safety and Sea Floor Instability

Description: Semi-analytical computational models for natural gas flow in hydrate reservoirs were developed and the effects of variations in porosity and permeability on pressure and temperature profiles and the movement of a dissociation front were studied. Experimental data for variations of gas pressure and temperature during propane hydrate formation and dissociation for crushed ice and mixture of crushed ice and glass beads under laboratory environment were obtained. A thermodynamically consistent model for multiphase liquid-gas flows trough porous media was developed. Numerical models for hydrate dissociation process in one dimensional and axisymmetric reservoir were performed. The computational model solved the general governing equations without the need for linearization. A detail module for multidimensional analysis of hydrate dissociation which make use of the FLUENT code was developed. The new model accounts for gas and liquid water flow and uses the Kim-Boshnoi model for hydrate dissociation.
Date: September 30, 2006
Creator: Ahmadi, Goodarz
Partner: UNT Libraries Government Documents Department

Fundamentals of Natural Gas and Species Flows from Hydrate Dissociation-Applications to Safety and Sea Floor Instability

Description: Natural gas production from the dissociation of methane hydrate in a confined reservoir by a depressurizing down-hole well was studied. The case that the well pressure was kept constant was treated and two different linearization schemes in an axisymmetric configuration were used in the analysis. For different fixed well pressures and reservoir temperatures, approximate self-similar solutions were obtained. Distributions of temperature, pressure and gas velocity field across the reservoir were evaluated. The distance of the decomposition front from the well and the natural gas production rate as functions of time were also computed. Time evolutions of the resulting profiles were presented in graphical forms and their differences with the constant well output results were studied. It was shown that the gas production rate was a sensitive function of well pressure and reservoir temperature. The sensitivity of the results to the linearization scheme used was also studied.
Date: September 1, 2005
Creator: Ahmadi, Goodarz
Partner: UNT Libraries Government Documents Department

Expertise Revisited: Reflecting on the Intersection of Science and Democracy in the Case of Fracking

Description: This dissertation aims to explain the conditions under which expertise can undermine democratic decision making. I argue that the root of the conflict between expertise and democracy lies in what I call insufficiently “representative” expertise – that is forms of scientific research that are not relevant to the policy questions at hand and that fail to make visible their hidden values dimensions. I claim that the scholarly literature on the problem of expertise fails to recognize and address the issue correctly, because it does not open the black box of scientific methodologies. I maintain that only by making sense of the methodological choices of experts in the context of policy making can we determine the relevance of research and reveal the hidden socio-political values and consequences. Using the case of natural gas fracking, I demonstrate how expert contributions – even though epistemically sound – can muddle democratic policy processes. I present four case studies from controversies about fracking to show how to contextualize scientific methodologies in the pertinent political process. I argue that the common problem across all case studies is the failure of expertise to sufficiently represent stakeholders’ problems and concerns. In this context, “representation” has three criteria: (1) the operational research questions on which the qualified experts work are relevant to stakeholders’ problems and concerns; (2) the non-epistemic values and consequences of epistemic choices of experts are compatible with social and political values and priorities; and (3) hidden values attached to facts are fully transparent and openly debated. In the conclusion, I propose a normative version of this representation theory that can be used to evaluate the appropriateness of expertise for democratic policy making. Instead of the value-free science ideal, I propose a new ideal to legitimately allow non-epistemic values in scientific reasoning without compromising the soundness of ...
Date: December 2015
Creator: Ahmadi, Mahdi
Partner: UNT Libraries

Catalytic partial oxidation reforming of hydrocarbon fuels.

Description: The polymer electrolyte fuel cell (PEFC) is the primary candidate as the power source for light-duty transportation systems. On-board conversion of fuels (reforming) to supply the required hydrogen has the potential to provide the driving range that is typical of today's automobiles. Petroleum-derived fuels, gasoline or some distillate similar to it, are attractive because of their existing production, distribution, and retailing infrastructure. The fuel may be either petroleum-derived or other alternative fuels such as methanol, ethanol, natural gas, etc. [1]. The ability to use a variety of fuels is also attractive for stationary distributed power generation [2], such as in buildings, or for portable power in remote locations. Argonne National Laboratory has developed a catalytic reactor based on partial oxidation reforming that is suitable for use in light-duty vehicles powered by fuel cells. The reactor has shown the ability to convert a wide variety of fuels to a hydrogen-rich gas at less than 800 C, temperatures that are several hundreds of degrees lower than alternative noncatalytic processes. The fuel may be methanol, ethanol, natural gas, or petroleum-derived fuels that are blends of various hydrocarbons such as paraffins, olefins, aromatics, etc., as in gasoline. This paper will discuss the results obtained from a bench-scale (3-kWe) reactor., where the reforming of gasoline and natural gas generated a product gas that contained 38% and 42% hydrogen on a dry basis at the reformer exit, respectively.
Date: September 21, 1998
Creator: Ahmed, S.
Partner: UNT Libraries Government Documents Department

Fuel-flexible partial oxidation reforming of hydrocarbons for automotive applications.

Description: Micro-reactor tests indicate that our partial oxidation catalyst is fuel-flexible and can reform conventional (gasoline and diesel) and alternative (ethanol, methanol, natural gas) fuels to hydrogen rich product gases with high hydrogen selectivity. Alcohols are reformed at lower temperatures (&lt; 600 C) while alkanes and unsaturated hydrocarbons require slightly higher temperatures. Cyclic hydrocarbons and aromatics have also been reformed at relatively low temperatures, however, a different mechanism appears to be responsible for their reforming. Complex fuels like gasoline and diesel, which are mixtures of a broad range of hydrocarbons, require temperatures of &gt; 700 C for maximum hydrogen production.
Date: June 7, 1999
Creator: Ahmed, S.; Carter, J. D.; Kopasz, J. P.; Krumpelt, M. & Wilkenhoener, R.
Partner: UNT Libraries Government Documents Department