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Quarterly Technical Progress Report - Investigation of Syngas Interaction in Alcohol Synthesis Catalysts
No full textThis report presents the work done on " Investigation of Syngas Interaction in Alcohol Synthesis Catalysts" during the last quarter. The major activity during this period is on FTIR absorption studies of Co/Cr catalysts using CO as a probe molecule. Transition metals cobalt and copper play significant roles in the conversion of syngas (CO + H2 ) to liquid fuels. With a view to examine the nature of interaction between CO and metal, the FTIR spectra of CO adsorbed on Co-Cr2 O3 composites were investigated. The results indicate that as cobalt loading increases, the intensity of the CO adsorption bands increase and several vibrational modes seem to be promoted. Heat treatment of the sample revealed two distinct processes of adsorption. Bands due to physisorption disappeared while bands due to chemisorption not only increased in intensity but persisted even after desorption. It seems that the physisorption process is more active when the catalyst is fresh and is hindered when carbidic/carbonyl formations occur on the metal surfaces
Improved Efficiency of Miscible C02 Floods and Enhanced Prospects for C02 Flooding Heterogeneous Reservoirs
No full textIn this quarter, we used parallel isolated composite core to test the effectiveness of foam on oil recovery efficiency. This composite core differs from the previous core in two areas: 1) Pyrex® glass beads were used in the center region to form a high permeability region and 2) a fired Berea sandstone was used in the annulus region to form a low permeability region. We also started to conduct surfactant adsorption measurements on coreflooding substrates. Static measurements with three anionic surfactants were conducted on Pyrex® glass beads. Surfactant concentrations were determined to calculate the amount of surfactant adsorbed on the substrate. The preliminary results showed that the loss of surfactant due to adsorption at 500 ppm concentration were 0.34 mg/cm 3 , 0.29 mg/cm 3 , and 0.19 mg/cm 3 for surfactants Alipa®CD128, Chaser-CD1040 and Dowfax-8390, respectively. Simulations were performed to assess the applicability of horizontal wells as a tool to increase oil recovery in CO2 injection projects
Geology and Petrophysical Characterization of the Ferron Sandstone for 3-D Simulation of a Fluvial-Deltaic Reservoir
No full textThe objective of this project is to develop a comprehensive, interdisciplinary, and quantitative characterization of a fluvial-deltaic reservoir which will allow realistic inter-well and reservoir-scale modeling to be constructed for improved oil-field development in similar reservoirs world-wide. The geological and petrophysical properties of the Cretaceous Ferron Sandstone in east-central Utah will be quantitatively determined. Both new and existing data will be integrated into a three-dimensional representation of spatial variations in porosity, storativity, and tensorial rock permeability at a scale appropriate for inter-well to regional-scale reservoir simulation. Four activities continued this quarter as part of the geological and petrophysical characterization of the fluvial-deltaic Ferron Sandstone in the Ivie Creek case-study area: (1) regional stratigraphic interpretation, (2) case-study evaluation, (3) reservoir modeling, and (4) technology transfer
Geological and Petrophysical Characterization of the Ferron Sandstone for 3-D Simulation of a Fluvial-Deltaic Reservoir
No full textThe objective of this project is to develop a comprehensive, interdisciplinary, and quantitative characterization of a fluvial-deltaic reser v oir which will allow realistic inter-well and reservoir-scale modeling to be constructed for improved oil-field development in similiar reservoirs world-wide. The geological and petrophysical properties of the Cretaceous Ferron Sandstone in east-central Utah will be quantitatively determined . Both new and existing data will be integrated into a three-dimensional representation of spatial variations in porosity, storativity, and tensorial rock permeability at a scale appropriate for inter-well to regional-scale reservoir simulation. Results could improve reservoir management through proper infill and extension drilling strategies, reduction of economic risks, increased recovery from existing oil fields, and more reliable reserve calculations . Transfer of the project results to the petroleum industry is an integral component of the project. Four activities continued this quarter as part of the geological and petrophysical characterization of the fluvial-deltaic Ferron Sandstone in the Ivie Creek case-study area: (1) geostatistics, (2) field description of clinoform bounding surfaces, (3) reservoir modeling, and (4) technology transfer
Improved Oil Recovery in Fluvial Dominated Deltaic Reservoirs of Kansas - Near-Term
No full textThe objective of this project is to address waterflood problems of the type found in Morrow sandstone reservoirs in southwestern Kansas and in Cherokee Group reservoirs in southeastern Kansas. Two demonstration sites operated by different independent oil operators are involved in this project. The Stewart Field is located in Finney County, Kansas and is operated by North American Resources Company. The Nelson Lease is located in Allen County, Kansas, in the N.E. Savonburg Field and is operated by James E. Russell Petroleum, Inc. General topics to be addressed are 1) reservoir management and performance evaluation, 2) waterflood optimization, and 3) the demonstration of recovery processes involving off-the-shelf technologies which can be used to enhance waterflood recovery, increase reserves, and reduce the abandonment rate of these reservoir types. In the Stewart Project, the reservoir management portion of the project conducted during Budget Period 1 involved performance evaluation. This included 1) reservoir characterization and the development of a reservoir database, 2) volumetric analysis to evaluate production performance, 3) reservoir modeling, 4) laboratory work, 5) identification of operational problems, 6) identification of unrecovered mobile oil and estimation of recovery factors, and 7) identification of the most efficient and economical recovery process. To accomplish these objectives the initial budget period was subdivided into three major tasks. The tasks were 1) geological and engineering analysis, 2) laboratory testing, and 3) unitization. Due to the presence of different operators within the field, it was necessary to unitize the field in order to demonstrate a field-wide improved recovery process. This work was completed and the project moved into Budget Period 2. Budget Period 2 objectives consisted of the design, construction, and operation of a field-wide waterflood utilizing state-of-the-art, off-the-shelf technologies in an attempt to optimize secondary oil recovery. To accomplish these objectives the second budget period was subdivided into five major tasks. The tasks were 1) design and construction of a waterflood plant, 2) design and construction of a water injection system, 3) design and construction of tank battery consolidation and gathering system, 4) initiation of waterflood operations and reservoir management, and 5) technology transfer. Tasks 1-3 have been completed and water injection began in October 1995. In the Savonburg Project, the reservoir management portion involves performance evaluation. This work included 1) reservoir characterization and the development of a reservoir database, 2) identification of operational problems, 3) identification of near wellbore problems such as plugging caused from poor water quality, 4) identification of unrecovered mobile oil and estimation of recovery factors, and 5) preliminary identification of the most efficient and economical recovery process i.e., polymer augmented waterflooding or infill drilling (vertical or horizontal wells). To accomplish this work the initial budget period was subdivided into four major tasks. The tasks included 1) geological and engineering analysis, 2) waterplant optimization, 3) wellbore cleanup and pattern changes, and 4) field operations. This work was completed and the project has moved into Budget Period 2. The Budget Period 2 objectives consisted of continual optimization of this mature waterflood in an attempt to optimize secondary and tertiary oil recovery. To accomplish these objectives the second budget period is subdivided into six major tasks. The tasks were 1) waterplant development, 2) profile modification treatments, 3) pattern changes, new wells and wellbore cleanups, 4) reservoir development (polymer flooding), 5) field operations, and 6) technology transfer
Investigating the Atomic Scale Superconducting Properties of Grain Boundaries in High-T(Sub c) Superconductors
No full textPresented at Fourteenth International Congress on Electron Microscopy Cancun, Mexico, August 31-September 4, 1998, and published in Proceedings Over ten years after the discovery of high-TC superconductors, their widespread application into viable device structures is still limited by the deleterious effect of grain boundaries. One of the main difficulties associated with understanding this effect is that transport measurements are usually performed on the micron scale. However, the critical parameter for superconductivity, the coherence length, is only ~lnm. To understand grain boundaries on a fundamental level it is therefore necessary to investigate the properties on this atomic scale; a scale attainable only by electron microscopy [12]. As an example of the observed properties of grain boundaries in YB~C~07d (YBCO), the V(I) curves recorded across a 24o boundary for several magnetic fields are shown m figure 1, To explain these properties, a model where the grain boundary is composed of equally sized and spaced dislocation cores separated by a very small fraction of much stronger links has been developed (figure 1). These strong links may carry either the depairing current, the JC of the grains or another Josephson current (a depairing current seems unlikely in view of the field dependence of the experimental data). The simulated behavior obtained for this model, where the fraction of strong links is x=O.005 and JC is the observed J=(B) of the grains, exhibits qualitatively similar behavior to the experimental data (figure 1). However, the fit is not perfect, suggesting that the strong links are more likely to be regions of grain boundary with a higher Josephson current, rather than links with the JC(B) of the grains. Using electron microscopy we can look for the origin of these stronger coupled regions at the grain boundary. Figure 2 shows a Z-contrast image of a similar high-angle [001] tilt grain boundary in YBCO. The image shows that there are some regions where the boundary plane is symmetric, while other regions where it is asymmetric. EELS measurements [1] at such boundaries have shown that the symmetry of the boundary plane plays an important role in determining the properties. Asymmetric high-angle grain boundaries show significant hole depletion whereas symmetric high angle grain boundaries show very little (Figure 3). This effect can be understood using bond valence sum analysis [3]. Figure 4 shows the Cu valence plots across regions of both high angle symmetric and asymmetric boundaries. The asymmetric boundaries show a dramatic drop in the copper valence (charge carrying holes are formed by hybridization of the O 2p and Cu 3d bands), whereas the symmetric regions show areas of dramatic decrease in valence and areas where there is no valence change. The origin of this behavior is that the asymmetric boundaries always show a reconstruction on the Cu sub-lattice while symmetric boundaries show a reconstruction on both the Cu and Y/Ba sub-lattices (figure 2). Regions of the boundary plane where the reconstruction exists on the Y/Ba sub-lattice may be the strong links seen in the transport measurements. Work is continuing to investigate this supposition [4]
Radionuclide Incorporation in Secondary Crystalline Minerals Resulting from Chemical Weathering of Selected Waste Glasses: Progress Report for Subtask 3d
No full textExperiments were conducted in fiscal year 1998 by Pacific Northwest National Laboratory to evaluate potential incorporation of radionuclides in secondary mineral phases that form from weathering vitrified nuclear waste glasses. These experiments were conducted as part of the Immobilized Low- Activity Waste-Petiormance Assessment (ILAW-PA) to generate data on radionuclide mobilization and transport in a near-field enviromnent of disposed vitrified wastes. An initial experiment was conducted to identify the types of secondary minerals that form from two glass samples of differing compositions, LD6 and SRL202. Chemical weathering of LD6 glass at 90oC in contact with an aliquot of uncontaminated Hanford Site groundwater resulted in the formation of a Crystalline zeolitic mineral, phillipsite. In contrast similar chemical weathering of SRL202 glass at 90"C resulted in the formation of a microcrystalline smectitic mineral, nontronite. A second experiment was conducted at 90"C to assess the degree to which key radionuclides would be sequestered in the structure of secondary crystalline minerals; namely, phillipsite and nontronite. Chemical weathering of LD6 in contact with radionuclide-spiked Hanford Site groundwater indicated that substantial ilactions of the total activities were retained in the phillipsite structure. Similar chemical weathering of SRL202 at 90"C, also in contact with radionuclide-spiked Hanford Site groundwater, showed that significant fractions of the total activities were retained in the nontronite structure. These results have important implications regarding the radionuclide mobilization aspects of the ILAW-PA. Additional studies are required to confkm the results and to develop an improved under- standing of mechanisms of sequestration and attenuated release of radionuclides to help refine certain aspects of their mobilization
Modeling Low-Dose-Rate Effects in Irradiated Bipolar-Base Oxides
No full textA physical model is developed to quantify the contribution of oxide-trapped charge to enhanced low-dose-rate gain degradation in bipolar junction transistors. Multiple-trapping simulations show that space charge limited transport is partially responsible for low-dose-rate enhancement. At low dose rates, more holes are trapped near the silicon-oxide interface than at high dose rates, resulting in larger midgap voltage shifts at lower dose rates. The additional trapped charge near the interface may cause an exponential increase in excess base current, and a resultant decrease in current gain for some NPN bipolar technologies
Estimation of upper bound probabilities for rare events resulting from nearby explosions
No full textIt is sometimes necessary to deploy, transport and store weapons containing high explosives (HE) in proximity. Accident analyses of these activities may include nearby explosion scenarios in which fragments from an exploding (donor) weapon impact a second (acceptor) weapon. Weapon arrays are designed to miti- gate consequences to potential acceptor weapons, but unless initiation of an accep- tor's HE is impossible, outcomes such as detonation must be considered. This paper describes an approach for estimating upper bound probabilities for fragment- dominated scenarios in which outcomes are expected to be rare events. Other aspectsl,z of nearby explosion problems were addressed previously. An example scenario is as follows. A donor weapon is postulated to detonate, and fragments of the donor weapon casing are accelerated outward. Some of the fragments may strike a nearby acceptor weapon whose HE is protected by casing materials. Most impacts are not capable of initiating the acceptor's HE. However, a sufficiently large and fast fragment could produce a shock-to-detonation transi- tion (SDT), which will result in detonation of the acceptor. Our approach will work for other outcomes of fragment impact, but this discussion focuses on detonation. Experiments show that detonating weapons typically produce a distribution of casing fragment sizes in which unusually large figments sometimes occur. Such fragments can occur because fragmentation physics includes predictable aspects as well as those best treated as random phenomena, such as the sizes of individual fragments. Likewise, some of the descriptors of fragment impact can be described as random phenomen% such as fragment orientation at impact (fragments typically are tumbling). Consideration of possibilities resulting from the various manifesta- tions of randomness can lead to worst-case examples tha~ in turn, lead to the out- comes of concern. For example, an unusually large fragment strikes an acceptor weapon with the worst possible orientation and in the acceptor's most vulnerable location. Intuitively, such an event clearly is very unlikely. Our approach is based on the quantification of such "unlikelihood." The randomness inherent in the physics is modeled explicitly. Worst-case events are pre&cted in simulations but appear with appropriately small frequencies and lead, in turn, to corresponding probability estimates. To make the complex physics involved in nearby explosions tractable, we keep some of worst-case approach. For example, we might assume that fragments strike with the worst-case orientation. Because some of the physics is modeled as worst case, our results become upper bound probability estimates. The remaining physics, which includes the random aspects, is modeled in a way that makes Monte Carlo esti- mation of probabilities possible. In the following, the different physical processes involved in nearby explosion scenarios are considered separately: fragmentation of the donor case, transport of the fragments to the acceptor, and impact of the fragment(s) and consequent effects on the acceptor warhead. The discussion focuses on the modeling choices, which inevitably limit the probability range over which outcome probabilities can be bounded by limiting the number of Monte Carlo simulations that are practical
Phase III: Implementation and Operation of the repository
No full textIn October all three Sun servers (3000, Ultra/II) were loaded, and we were able to demonstrate the complete system, databases, web front-page, and GeoTrek to a large audience. All systems required for the web-based metadata catalog are in place and operational. Version 54 of the PetroTrek/GeoTrek software was loaded in December and is being tested. It is expected this version will be placed in the production environment for beta testing in January. Installation of the Bureau of Economic Geology (BEG) databases on the IS Houston server was completed and GeoTrek was loaded on BEG's server in Austin. Installation of the entire MMS well data set (35,000 records) was completed and it will be moved to the production environment for beta testing in January. The Eastern Gulf Region PTTC interior salt basin data set was prepared and it will be loaded in January. The Gulf of Mexico PGS seismic data set was prepared and loaded in December. The web-site front pages for the NGDRS GeoTrek Metadata Catalog are 70 percent completed and write-ups for the tutorials are scheduled to be completed in January. Ten users identified to be beta testers are actively testing the system