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At least 1,711 records · Page 95

Clearwater and Wineskin Sub-CAU Flow and Transport Models

The Clearwater (U12q) test of 1963 and the Wineskin (U12r) test of 1969 each have a 200 kt maximum announced yield (USDOE, 2000). Together, these two vertical shaft tests constitute about 25% of the total maximum yield on Rainier Mesa (Bowen et al., 2001). Their western location requires assessment of radionuclide flux to the Timber Mountain regional volcanic aquifer (Fenelon et al., 2008) or Redrock Valley Aquifer or “RVA” (NSTec, 2007). The Clearwater and Wineskin sub-CAU modeling objective is to generate realistic distributions of groundwater flow and radionuclide transport flux (realizations) using ranges of flow and transport properties bounded by data, flow calibration, and radionuclide concentration measurements. Key uncertainty variables include: (1) fraction of infiltration reaching the RVA, (2) fracture permeability and porosity in the TCU, (3) altered zone permeability and porosity enhancement, (4) hydraulic head in the RVA adjacent to the tests, (5) the radionuclide source term, and (6) transport mobility properties including Kd, tortuosity, and penetration depth of radionuclides into the matrix. Between 225 and 2160 realizations of radionuclide transport were generated for each of the 11 radionuclide sources (see Table 1), with the number of realizations depending on number of cases needed to address uncertainty variables - 5 flow cases, 3 transport mobility cases, 3 source term magnitudes, 3 to 5 source term spatial distributions, 1 to 4 melt glass partition fractions, and 1 to 3 melt glass dissolution fractions. Realizations exceeding 0.1 MCL to the RVA at any time between 0 and 1000 years post-test time were forwarded to the CAU model.

58 GEOSCIENCES↗

HERMES Model Modifications and Applications 2012

HERMES was developed to meet requirements for a model to describe explosive response to impacts that do not produce prompt detonation, but can include delayed detonations such as DDT and XDT. Such response is termed High Explosive Violent Response (HEVR). The HERMES model includes a constitutive description of strength as a function of pressure, strain-rate, strain, and ambient temperature; the development of damage including fragmentation and porosity; the conditions leading to ignition; the propagation of a burning reaction through the volume of damaged explosive; the burn-up of the damaged and undamaged explosive; and the development of detonation using the Computational Reaction Evolution dependent on Entropy (S) and Time (CREST) detonation model. CREST can distinguish gradual pressure increases from shock waves, and also predict the increase in shock sensitivity to detonation that results from increased porosity. This year HERMES has been implemented as a User Defined Function in ALE 3D. As a result, modifications to the model can be implemented in a timely fashion asynchronously from the ALE 3D distribution process. There are differences between the implementation of HERMES in ALE 3D and the implementation in LS DYNA. The major difference is the propagation of an ignition front from an element that has started to burn. In LS DYNA, the time at which an element begins to burn is based on the minimum line-of-sight distance between the element and any previously ignited element. In ALE 3D the time to burn is based on a level-set method that propagates the ignition front from all elements that were previously ignited. The ALE 3D implementation modifies the time of ignition when element deformation changes the distance from the element to the source. The LS DYNA implementation does not. There are also differences in the implementation of artificial viscosity, which is important for CREST since the artificial viscosity increases the element entropy in a shock. In general, however, the differences have proven minor. In collaboration with the Atomic Weapons Establishment, UK (AWE), we have characterized two additional explosives – PETN and Composition B, a mixture of 60% RDX and 40% TNT by weight. Applications of HERMES to these explosives are described below.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Reservoir Characterization of Bridgeport and Cypress Sandstones in Lawrence Field Illinois to Improve Petroleum Recovery by Alkaline-Surfactant-Polymer Flood

Within the Illinois Basin, most of the oilfields are mature and have been extensively waterflooded with water cuts that range up to 99% in many of the larger fields. In order to maximize production of significant remaining mobile oil from these fields, new recovery techniques need to be researched and applied. The purpose of this project was to conduct reservoir characterization studies supporting Alkaline-Surfactant-Polymer Floods in two distinct sandstone reservoirs in Lawrence Field, Lawrence County, Illinois. A project using alkaline-surfactantpolymer (ASP) has been established in the century old Lawrence Field in southeastern Illinois where original oil in place (OOIP) is estimated at over a billion barrels and 400 million barrels have been recovered leaving more than 600 million barrels as an EOR target. Radial core flood analysis using core from the field demonstrated recoveries greater than 20% of OOIP. While the lab results are likely optimistic to actual field performance, the ASP tests indicate that substantial reserves could be recovered even if the field results are 5 to 10% of OOIP. Reservoir characterization is a key factor in the success of any EOR application. Reservoirs within the Illinois Basin are frequently characterized as being highly compartmentalized resulting in multiple flow unit configurations. The research conducted on Lawrence Field focused on characteristics that define reservoir compartmentalization in order to delineate preferred target areas so that the chemical flood can be designed and implemented for the greatest recovery potential. Along with traditional facies mapping, core analyses and petrographic analyses, conceptual geological models were constructed and used to develop 3D geocellular models, a valuable tool for visualizing reservoir architecture and also a prerequisite for reservoir simulation modeling. Cores were described and potential permeability barriers were correlated using geophysical logs. Petrographic analyses were used to better understand porosity and permeability trends in the region and to characterize barriers and define flow units. Diagenetic alterations that impact porosity and permeability include development of quartz overgrowths, sutured quartz grains, dissolution of feldspar grains, formation of clay mineral coatings on grains, and calcite cementation. Many of these alterations are controlled by facies. Mapping efforts identified distinct flow units in the northern part of the field showing that the Pennsylvanian Bridgeport consists of a series of thick incised channel fill sequences. The sandstones are about 75-150 feet thick and typically consist of medium grained and poorly sorted fluvial to distributary channel fill deposits at the base. The sandstones become indistinctly bedded distributary channel deposits in the main part of the reservoir before fining upwards and becoming more tidally influenced near their top. These channel deposits have core permeabilities ranging from 20 md to well over 1000 md. The tidally influenced deposits are more compartmentalized compared to the thicker and more continuous basal fluvial deposits. Fine grained sandstones that are laterally equivalent to the thicker channel type deposits have permeabilities rarely reaching above 250 md. Most of the unrecovered oil in Lawrence Field is contained in Pennsylvanian Age Bridgeport sandstones and Mississippian Age Cypress sandstones. These reservoirs are highly complex and compartmentalized. Detailed reservoir characterization including the development of 3-D geologic and geocellular models of target areas in the field were completed to identify areas with the best potential to recover remaining reserves including unswept and by-passed oil. This project consisted of tasks designed to compile, interpret, and analyze the data required to conduct reservoir characterization for the Bridgeport and Cypress sandstones in pilot areas in anticipation of expanded implementation of ASP flooding in Lawrence Field. Geologic and geocellular modeling needed for reservoir characterization and reservoir simulation were completed as prerequisites for design of efficient ASP flood patterns. Characterizing the complex reservoir geology that identifies the geologic conditions that will optimize oil recoveries for expansion of the ASP pilots in the Bridgeport and Cypress sandstones to other areas of Lawrence Field is the primary objective of this project. It will permit evaluation of efficiency of oil recovery from Bridgeport and Cypress sandstone reservoirs using ASP technology. Additionally evaluation of similar Pennsylvanian and Chesterian reservoirs shows that it is likely that ASP flood technology can be successfully applied to similar reservoirs in the Illinois Basin as well as to other U.S. reservoirs. Chemical flooding was introduced in stages with the first flood initiated in 2010 and a second offset pilot project initiated during 2011. Rex Energy Corporation is reporting a positive response on its ASP Middagh pilot project in the Pennsylvanian Bridgeport B reservoir, Lawrence Field. Oil response in the 15 acre flood has continued to show an increase in oil cut from 1% to 12%. Total pattern production increased from 16 BOPD and stabilized at a range of 65-75 BOPD in the last three months of 2011. Peak production rose to 100 + BOPD. Oil cut in the pilot increased for 1.0% to ~ 12.0% with an individual well showing oil cuts greater than 20%. A second, 58 acre pilot (Perkins-Smith) adjacent to and likely in communication with the Middagh pilot has been initiated. Preliminary brine injection has been implemented and ASP injection was initiated in mid-2012. Response is expected by mid-2013 with peak recovery expected by late 2013. Rex Energy is projecting full scale expansion with the next step of development being a 351 acre project scheduled to begin in mid-2013. Preliminary development has been initiated in this Delta Unit area located in the south half of section 32, T4N, R12W.

02 PETROLEUM↗

Petrologic and Petrophysical Evaluation of the Dallas Center Structure, Iowa, for Compressed Air Energy Storage in the Mount Simon Sandstone

The Iowa Stored Energy Plant Agency selected a geologic structure at Dallas Center, Iowa, for evaluation of subsurface compressed air energy storage. The site was rejected due to lower-than-expected and heterogeneous permeability of the target reservoir, lower-than-desired porosity, and small reservoir volume. In an initial feasibility study, permeability and porosity distributions of flow units for the nearby Redfield gas storage field were applied as analogue values for numerical modeling of the Dallas Center Structure. These reservoir data, coupled with an optimistic reservoir volume, produced favorable results. However, it was determined that the Dallas Center Structure cannot be simplified to four zones of high, uniform permeabilities. Updated modeling using field and core data for the site provided unfavorable results for air fill-up. This report presents Sandia National Laboratories' petrologic and petrophysical analysis of the Dallas Center Structure that aids in understanding why the site was not suitable for gas storage.

Heath, Jason E.↗

Fuel Performance Modeling Results for Representative FCRD Irradiation Experiments: Projected Deformation in the Annular AFC-3A U-10Zr Fuel Pins and Comparison to Alternative Designs

The objective of the present study was to predict the outcome of the AFC-3A annular U-10Zr fuel irradiation experiment. Specifically, the study attempted to predict whether the annular fuel will swell inward and fill the annulus, or swell outward resulting in an undesirable cladding deformation. It was predicted that both 55% and 75% annular fuels operating at 350 W/cm for 201 days will swell inward and partially fill the annulus which signifies a positive outcome of the experiment. The driving mechanism for such behavior is the fuel creep under the compressive stress exerted on the fuel by the cladding as a result of the fuel cladding mechanical interaction. Comparison with the solid fuel revealed that the annular fuel is expected to swell less early in life due to the mechanical constraint provided by the cladding. Furthermore, mechanical constraint is expected to yield a marked reduction of the axial elongation of the annular fuel as compared to the solid fuel. The prediction is based on the assumption that the annular fuel is not capable of moving axially relative to the cladding after the two come in contact. Post irradiation examination results would be very useful to assess the validity of this assumption. Specifically, underprediction of the axial growth would point to the fact that some slippage of the fuel relative to the cladding occurs after the onset of the FCMI. As fuel creep plays the major role in the deformation of the annular fuel, the contributions from the thermal and irradiation induced creep to the total creep rate of fuel were examined to provide guidance for possible creep testing experiments of the fuel (separate effect tests). It was found that irradiation induced creep dominates deformation of the fresh fuel at low temperatures. At high temperatures, and in the case of porous fuel, the thermal creep of the fuel becomes dominant and irradiation induced creep can be neglected. Fission gas induced porosity seems to accelerate fuel creep drastically. Recognizing the sensitivity of the fuel creep to the porosity, additional studies exploring this phenomenon and verifying published equations either experimentally or through computation may benefit the understanding of the annular fuel behavior.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

ASC PEM Materials Modeling Overview: Focus on Predicting Response of Metals [Slides]

In general, the large / high rate deformation process involves high pressure and temperature, finite elasticity, phase change, localization, porosity initiation, porosity growth, and coalescence dominated by localized deformation. These physical events are statistical, coupled, occur over several length scales, and intimately involves the microstructure. Understanding these complex thermo-mechanical processes is critical to our ability to numerically represent and predict these deformation events. ASC Materials is generally responsible for the modeling of 12-15 different metallic materials subjected to a broad range of conditions. This talk discusses current approaches and unanswered questions in the areas of high rate strength, phase transformations, and damage and failure.

36 MATERIALS SCIENCE↗

Risk Evaluation for CO 2 Geosequestration in the Knox Supergroup, Illinois Basin (Final Report)

This report describes a process and provides seed information for identifying and evaluating risks pertinent to a hypothetical carbon dioxide (CO 2 ) capture and sequestration (CCS) project. In the envisioned project, the target sequestration reservoir rock is the Potosi Formation of the Knox Supergroup. The Potosi is identified as a potential target formation because (1) at least locally, it contains vuggy to cavernous layers that have very high porosity, and (2) it is present in areas where the deeper Mt. Simon Sandstone (a known potential reservoir unit) is absent or nonporous. The key report content is discussed in Section 3.3, which describes two lists of Features, Events, and Processes (FEPs) that should be considered during the design stage of such a project. These lists primarily highlight risk elements particular to the establishment of the Potosi as the target formation in general. The lists are consciously incomplete with respect to risk elements that would be relevant for essentially all CCS projects regardless of location or geology. In addition, other risk elements specific to a particular future project site would have to be identified. Sources for the FEPs and scenarios listed here include the iconic Quintessa FEPs list developed for the International Energy Agency Greenhouse Gas (IEAGHG) Programme; previous risk evaluation projects executed by Schlumberger Carbon Services; and new input solicited from experts currently working on aspects of CCS in the Knox geology. The projects used as sources of risk information are primarily those that have targeted carbonate reservoir rocks similar in age, stratigraphy, and mineralogy to the Knox-Potosi. Risks of using the Potosi Formation as the target sequestration reservoir for a CCS project include uncertainties about the levels of porosity and permeability of that rock unit; the lateral consistency and continuity of those properties; and the ability of the project team to identify suitable (i.e., persistently porous and permeable) injection depths within the overall formation. Less direct implications include the vertical position of the Potosi within the rock column and the absence of a laterally extensive shale caprock immediately overlying the Potosi. Based on modeling work done partly in association with this risk report, risks that should also be evaluated include the ability of available methods to predict and track the development of a CO 2 plume as it migrates away from the injection point(s). The geologic and hydrodynamic uncertainties present risks that are compounded at the stage of acquiring necessary drilling and injection permits. It is anticipated that, in the future, a regional geologic study or CO 2 -emitter request may identify a small specific area as a prospective CCS project site. At that point, the FEPs lists provided in this report should be evaluated by experts for their relative levels of risk. A procedure for this evaluation is provided. The higher-risk FEPs should then be used to write project-specific scenarios that may themselves be evaluated for risk. Then, actions to reduce and to manage risk can be described and undertaken. The FEPs lists provided as Appendix 2 should not be considered complete, as potentially the most important risks are ones that have not yet been thought of. But these lists are intended to include the most important risk elements pertinent to a Potosi-target CCS project, and they provide a good starting point for diligent risk identification, evaluation, and management.

54 ENVIRONMENTAL SCIENCES↗

Processing of Sintered Mo Disks Using Hydrogen Peroxide

Dissolution studies performed on NorthStar and ORNL disks show that an increase in sintering temperature has a negative effect on dissolution rates in 30% hydrogen peroxide. This is due to changes in the microstructure of sintered Mo powder. At higher sintering temperatures, the powder particles coalesce, form diffusion bonds, and grow into larger grains, which reduce the open porosity of the disks. The remaining porosity becomes trapped within the grains, and therefore the dissolution rates are very low. We also observed that different starting materials lead to different dissolution properties, and in some cases, even high sintering temperature at 1600°C does not produce disks with high packing densities. Studies with NorthStar disks showed that increased packing density can be achieved by increased pressing conditions without affecting the dissolution rates if mild sintering conditions are used. Future experiments will focus on producing sintered Mo disks produced from recovered Mo material and on optimizing the sintering process to produce disks with >90% packing density and good dissolution rates.

Dissolution↗

Nanostructured polymeric materials for hydrogen storage

The objective of this project is to develop a new class of hydrogen storage adsorbent, nanostructured porous organic polymers (POPs), through collaboration between Argonne National Laboratory and The University of Chicago. POPs have excellent thermal stability and tolerance to gas contaminants such as moisture. They also have low skeleton density and high intrinsic porosity via covalent bonds, capable of maintaining specific surface area (SSA) during high pressure pelletizing for better volumetric density. Furthermore, they can be produced at a commercial scale with the existing industrial infrastructure. The team’s approach focused on improving hydrogen uptake capacity and the heat of adsorption by enhancing SSA, porosity control, and framework-adsorbate interactions through rational design and synthesis at the molecular level. The design principles aim at improving the following attributes of the polymers: (a) high SSA to provide sufficient interface with H2; (b) narrow pore diameter to enhance van der Waals interactions in the confined space; and (c) “metallic” features, either through π- conjugation or metal doping, to promote electronic orbital interactions with hydrogen.

36 MATERIALS SCIENCE↗

Multi-scale modeling of inter-granular fracture in UO2

A hierarchical multi-scale approach is pursued in this work to investigate the influence of porosity, pore and grain size on the intergranular brittle fracture in UO2. In this approach, molecular dynamics simulations are performed to obtain the fracture properties for different grain boundary types. A phase-field model is then utilized to perform intergranular fracture simulations of representative microstructures with different porosities, pore and grain sizes. In these simulations the grain boundary fracture properties obtained from molecular dynamics simulations are used. The responses from the phase-field fracture simulations are then fitted with a stress-based brittle fracture model usable at the engineering scale. This approach encapsulates three different length and time scales, and allows the development of microstructurally informed engineering scale model from properties evaluated at the atomistic scale.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Uniaxial Creep as a Control on Mercury Intrusion Capillary Pressure in Consolidating Rock Salt

The nature of geologic disposal of nuclear waste in salt formations requires validated and verified two-phase flow models of transport of brine and gas through intact, damaged, and consolidating crushed salt. Such models exist in other realms of subsurface engineering for other lithologic classes (oil and gas, carbon sequestration etc. for clastics and carbonates) but have never been experimentally validated and parameterized for salt repository scenarios or performance assessment. Models for waste release scenarios in salt back-fill require phenomenological expressions for capillary pressure and relative permeability that are expected to change with degree of consolidation, and require experimental measurement to parameterize and validate. This report describes a preliminary assessment of the influence of consolidation (i.e. volume strain or porosity) on capillary entry pressure in two phase systems using mercury injection capillary pressure (MICP). This is to both determine the potential usefulness of the mercury intrusion porosimetry method, but also to enable a better experimental design for these tests. Salt consolidation experiments are performed using novel titanium oedometers, or uniaxial compression cells often used in soil mechanics, using sieved run-of-mine salt from the Waste Isolation Pilot Plant (WIPP) as starting material. Twelve tests are performed with various starting amounts of brine pore saturation, with axial stresses up to 6.2 MPa (~900 psi) and temperatures to 90°C. This corresponds to UFD Work Package 15SN08180211 milestone “FY:15 Transport Properties of Run-of-Mine Salt Backfill – Unconsolidated to Consolidated”. Samples exposed to uniaxial compression undergo time-dependent consolidation, or creep, to various degrees. Creep volume strain-time relations obey simple log-time behavior through the range of porosities (~50 to 2% as measured); creep strain rate increases with temperature and applied stress as expected. Mercury porosimetry is used to determine characteristic capillary pressure curves from a series of consolidation tests and show characteristic saturation-capillary pressure curves that follow the common van Genuchten (1978, 1980) formulation at low stresses. Higher capillary pressure data are suspect due to the large potential for sample damage, including fluid inclusion decrepitation and pore collapse. Data are supportive of use of the Leverett “J” function (Leverett, 1941) to use for scaling characteristic curves at different degrees of consolidation, but better permeability determinations are needed to support this hypothesis. Recommendations for further and refined testing are made with the goal of developing a self- consistent set of constitutive laws for granular salt consolidation and multiphase (brine-air) flow.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

CFD Simulations of a Regenerative Process for Carbon Dioxide Capture in Advanced Gasification Based Power Systems

This project describes the work carried out to prepare a highly reactive and mechanically strong MgO based sorbents and to develop a Population Balance Equations (PBE) approach to describe the evolution of the particle porosity distribution that is linked with Computational Fluid Dynamics (CFD) to perform simulations of the CO2 capture and sorbent regeneration. A large number of MgO-based regenerable sorbents were prepared using low cost and abundant dolomite as the base material. Among various preparation parameters investigated the potassium/magnesium (K/Mg) ratio was identified as the key variable affecting the reactivity and CO2 capacity of the sorbent. The optimum K/Mg ratio is about 0.15. The sorbent formulation HD52-P2 was identified as the “best” sorbent formulation and a large batch (one kg) of the sorbent was prepared for the detailed study. The results of parametric study indicate the optimum carbonation and regeneration temperatures are 360° and 500°C, respectively. The results also indicate that steam has a beneficial effect on the rate of carbonation and regeneration of the sorbent and that the reactivity and capacity of the sorbent decreases in the cycling process (sorbent deactivation). The results indicate that to achieve a high CO2 removal efficiency, the bed of sorbent should be operated at a temperature range of 370-410°C which also favors production of hydrogen through the WGS reaction. To describe the carbonation reaction kinetics of the MgO, the Variable Diffusivity shrinking core Model (VDM) was developed in this project, which was shown to accurately fit the experimental data. An important advantage of this model is that the changes in the sorbent conversion with time can be expressed in an explicit manner, which will significantly reduce the CFD computation time. A Computational Fluid Dynamic/Population Balance Equations (CFD/PBE) model was developed that accounts for the particle (sorbent) porosity distribution and a new version of the method of moments, called Finite size domain Complete set of trial functions Method Of Moments (FCMOM) was used to solve the population balance equations. The PBE model was implemented in a commercial CFD code, Ansys Fluent 13.0. The code was used to test the model in some simple cases and the results were verified against available analytical solution in the literature. Furthermore, the code was used to simulate CO2 capture in a packed-bed and the results were in excellent agreement with the experimental data obtained in the packed bed. The National Energy Laboratory (NETL) Carbon Capture Unit (C2U) design was used in simulate of the hydrodynamics of the cold flow gas/solid system (Clark et al.58). The results indicate that the pressure drop predicted by the model is in good agreement with the experimental data. Furthermore, the model was shown to be able to predict chugging behavior, which was observed during the experiment. The model was used as a base-case for simulations of reactive flow at elevated pressure and temperatures. The results indicate that by controlling the solid circulation rate, up to 70% CO2 removal can be achieved and that the solid hold up in the riser is one of the main factors controlling the extent of CO2 removal. The CFD/PBE simulation model indicates that by using a simulated syngas with a composition of 20% CO2, 20% H2O, 30% CO, and 30% H2, the composition (wet basis) in the reactor outlet corresponded to about 60% CO2 capture with and exit gas containing 65% H2. A preliminary base-case-design was developed for a regenerative MgO-based pre-combustion carbon capture process for a 500 MW IGCC power plant. To minimize the external energy requirement, an extensive heat integration network was developed in Aspen/HYSYS® to produce the steam required in the regenerator and heat integration. In this process, liquid CO2 produced at 50 atm can easily be pumped and sequestered or stored. The preliminary economic analyses indicate that the estimated cost of carbon v capture is in the range of $31-$44/ton, suggesting that a regenerative MgO-Based process can be a viable option for pre-combustion carbon dioxide capture in advanced gasification based power systems.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Evaluation of Additive Manufacturing for Stainless Steel Components

This collaboration between Oak Ridge National Laboratory and General Electric Company aimed to evaluate the mechanical properties, microstructure, and porosity of the additively manufactured 316L stainless steel by ORNL’s Renishaw AM250 machine for nuclear application. The program also evaluated the stress corrosion cracking and corrosion fatigue crack growth rate of the same material in high temperature water environments. Results show the properties of this material to be similar to the properties of 316L stainless steel fabricated additively with equipment from other manufacturers with slightly higher porosity. The stress corrosion crack growth rate is similar to that for wrought 316L stainless steel for an oxygenated high temperature water environment and slightly higher for a hydrogenated high temperature water environment. Optimized heat treatment of this material is expected to improve performance in high temperature water environments.

36 MATERIALS SCIENCE↗

Experimental deformation in sandstone, carbonates and quartz aggregate

The first part of my thesis is mainly focused on the effect of grain size distribution on compaction localization in porous sandstone. To identify the microstructural parameters that influence compaction band formation, I conducted a systematic study of mechanical deformation, failure mode and microstructural evolution in Bleurswiller and Boise sandstones, of similar porosity (~25%) and mineralogy but different sorting. Discrete compaction bands were observed to develop over a wide range of pressure in the Bleurswiller sandstone that has a relatively uniform grain size distribution. In contrast, compaction localization was not observed in the poorly sorted Boise sandstone. My results demonstrate that grain size distribution exerts important influence on compaction band development, in agreement with recently published data from Valley of Fire and Buckskin Gulch, as well as numerical studies. The second part aimed to improve current knowledge on inelastic behavior, failure mode and brittle-ductile transition in another sedimentary rock, porous carbonates. A micritic Tavel (porosity of ~13%) and an allochemical Indiana (~18%) limestones were deformed under compaction in wet and dry conditions. At lower confining pressures, shear localization occurred in brittle faulting regime. Through transitional regime, the deformation switched to cataclastic flow regime at higher confining pressure. Specifically in the cataclastic regime, the (dry and wet) Tavel and dry Indiana failed by distributed cataclastic flow, while in contrast, wet Indiana failed as compaction localization. My results demonstrate that different failure modes and mechanical behaviors under different deformation regimes and water saturation are fundamental prior to any geophysical application in porous carbonates. The third part aimed to focus on investigating compaction on quartz aggregate starting at low (MPa) using X-ray diffraction. We report the diffraction peak evolution of quartz with increasing pressures. Through evaluating the unit cell lattice parameters and the volume of the quartz sample, macroscopic stress and strain were resolved. Moreover, we observed quartz peak broadened asymmetrically at low pressure, such extent is more prominent in axial than in radial direction. Our evaluation on peak [101] (highest intensity among peaks) demonstrated that full width at half maximum can be a good proxy for microscopic stress distribution. We observed deviations in the pressurevolume curves at P = ~0.4 GPa and speculated that it was the point of which onset of grain crushing and pore collapse occur in quartz. This is on the same order of which onset of grain crushing (commonly known as P*) is observed in sandstones in the rock mechanics literature. This demonstrated that there is potential in estimating grain crushing and pore collapse pressure with our technique.

58 GEOSCIENCES↗

Final Report

This project employed a continuum approach to formulate an elastic constitutive model for Castlegate sandstone. The resulting constitutive framework for high porosity sandstone is thermodynamically sound, (i.e., does not violate the 1st and 2nd law of thermodynamics), represents known material constitutive response, and is able to be calibrated using available mechanical response data. To authenticate the accuracy of this model, a series of validation criteria were employed, using an existing mechanical response data set for Castlegate sandstone. The resulting constitutive framework is applicable to high porosity sandstones in general, and is tractable for scientists and researchers endeavoring to solve problems of practical interest.

02 PETROLEUM↗

Additive Manufacturing of Porous Metal

Currently, helium is obtained through separation from natural gas. The current industrial process incurs significant costs and requires large energy resources to successfully achieve separation. Through utilizing Additive Manufacturing (AM) technologies it is possible to reduce both of these burdens when refining helium gas. The ability to engineer porosity levels within Inconel 718 discs for controlled separation of helium from natural gas was investigated. Arrays of samples fabricated using the electron beam melting process were analyzed for their relative porosity density. Based upon the measurements, full scale discs were fabricated, and subsequently tested to determine their effectiveness in separating helium from liquefied natural gas.

03 NATURAL GAS↗

Characterization of the Triassic Newark Basin of New York and New Jersey for geologic storage of carbon dioxide

The Newark Basin is a Triassic-aged rift basin underlying densely populated, industrialized sections of New York, New Jersey and Pennsylvania. The Basin is an elongate half-graben encompassing an area of more than 7,510 square-kilometers (2,900 square-miles), and could represent a key storage component for commercial scale management of carbon dioxide emissions via geologic sequestration. The project team first acquired published reports, surface and subsurface maps, and seismic data, which formed the basis for a three-dimensional model framework for the northern end of the Basin incorporating stratigraphic, hydrologic, and water quality data. Field investigations included drilling, coring, and logging of two stratigraphic test borings in Clarkstown, NY (Exit 14 Tandem Lot Well No. 1), drilled to a depth of 2,099 meters (6,885 feet); and Palisades, NY (Lamont-Doherty Earth Observatory Test Well No. 4) drilled to a depth of 549 meters (1,802 feet). Two two-dimensional seismic reflection data lines arrayed perpendicularly were acquired by Schlumberger/WesternGeco to help characterize the structure and stratigraphy and as part of pre-drilling field screening activities for the deep stratigraphic borehole. A total of 47 meters (155 feet) of continuous whole core was recovered from the Tandem Lot boring from depths of 1,393 meters (4,570 feet) to 1,486 meters (4,877 feet). Twenty-five horizontal rotary cores were collected in mudstones and sandstones in the surface casing hole and fifty-two cores were taken in various lithologies in the deep borehole. Rotary core plugs were analyzed by Weatherford Laboratories for routine and advanced testing. Rotary core plug trim end thin sections were evaluated by the New York State Museum for mineralogical analysis and porosity estimation. Using core samples, Lawrence Berkley National Laboratory designed and completed laboratory experiments and numerical modeling analyses to characterize the dissolution and reaction of carbon dioxide with formation brine and minerals, and resulting effects on injection rate, pressure, effective storage volume, and carbon dioxide migration within a prospective sandstone reservoir. $$Three potential porous and permeable sandstone units were identified in the Passaic Formation at the New York State Thruway Exit 14 location. Potential Flow Unit 1, at a depth of 643 meters (2,110 feet) to 751 meters (2,465 feet); Potential Flow Unit 2 at a depth of 853 meters (2,798 feet) to 1,000 meters (3,280 feet); and Potential Flow Unit 3, at a depth of 1,114 meters (3,655 feet) to 1,294 meters (4,250 feet). Reactive transport simulations of interactions between carbon dioxide, brine and formation minerals were carried out to evaluate changes in formation water chemistry, mineral precipitation and dissolution reactions, and any potential resulting effects on formation permeability. The experimental and modeling analyses suggest that mineral precipitation and dissolution reactions (within the target formation) are not expected to lead to significant changes to the underground hydrologic system over time frames (~30 years) typically relevant for carbon dioxide injection operations. Key findings of this basin characterization study include an estimate of carbon dioxide storage capacity in the Newark Basin. Assuming an average porosity of twelve percent and an aquifer volume of 6.1E+12 meters3, calculated ranges of likely storage capacity range from 1.9 – 20.2 gigatonnes under high temperature (low carbon dioxide density) conditions; and 2.9 – 30.2 gigatonnes under low temperature (low carbon dioxide density) conditions. Intra-basin faulting, geometry of the Palisades Sill, and the presence of altered meta-sediments above and below the Sill, increase potential compartmentalization within the basin. A structural/stratigraphic trap type may occur where porous/permeable sediments are cross-cut by the Palisades Sill. Potential injection intervals are present within the Stockton Formation of the Newark Basin. Additional porous/permeable intervals may be present within sandstones of the Passaic Formation, increasing projected storage capacity. Deeper wedges of strata are likely present in the deeper portions of the basin in southern New York and into northern New Jersey. Abundant mudstones are present in the Passaic, Lockatong, and Stockton Formations. These intervals have the requisite petrophysical properties to form effective primary and secondary containment intervals to industrial-scale sequestration of carbon dioxide in the Newark Basin. Hydro-thermally altered meta-sediments in the region immediately surrounding the top and base of the Palisades Sill is devoid of porosity/permeability and forms an additional effective lateral/vertical sealing cap rock.

58 GEOSCIENCES↗

Graphite Microstructural Characterization Using Time-Domain and Correlation-Based Ultrasonics

Among techniques that have been used to determine elastic modulus in nuclear graphites, ultrasonic methods have enjoyed wide use and standards using contacting piezoelectric tranducers have been developed to ensure repeatability of these types of measurements. However, the use of couplants and the pressures used to effectively couple transducers to samples can bias measurements and produce results that are not wholly related to the properties of the graphite itself. In this work, we have investigated the use of laser ultrasonic methods for making elastic modulus measurements in nuclear graphites. These methods use laser-based transmitters and receivers to gather data and do not require use of ultrasonic couplants or mechanical contact with the sample. As a result, information directly related to the elastic responses of graphite can be gathered even if the graphite is porous, brittle and compliant. In particular, we have demonstrated the use of laser ultrasonics for the determination of both Young’s modulus and shear modulus in a range of nuclear graphites including those that are being considered for use in future nuclear reactors. These results have been analyzed to assess the contributions of porosity and microcracking to the elastic responses of these graphites. Laser-based methods have also been used to assess the moduli of NBG-18 and IG-110 where samples of each grade were oxidized to produce specific changes in porosity. These data were used to develop new models for the elastic responses of nuclear graphites and these models have been used to infer specific changes in graphite microstructure that occur during oxidation that affect elastic modulus. Specifically, we show how ultrasonic measurements in oxidized graphites are consistent with nano/microscale oxidation processes where basal plane edges react more readily than basal plane surfaces. We have also shown the use of laser-based methods to perform shear-wave birefringence measurements and have shown how these measurements can be used to assess elastic anisotropy in nuclear graphites. Using models developed in this program, ultrasonic data were interpreted to extract orientation distribution coefficients that could be used to represent anisotropy in these materials. This demonstration showed the use of ultrasonic methods to quantify anisotropy and how these methods provide more detailed information than do measurements of thermal expansion – a technique commonly used for assessing anisotropy in nuclear graphites. Finally, we have employed laser-based, ultrasonic-correlation techniques in attempts to quantify aspects of graphite microstructure such as pore size and distribution. Results of these measurements indicate that additional work must be performed to make this ultrasonic approach viable for quantitative microstructural characterization.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗