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In-situ borehole seismic monitoring of injected CO2 at the FrioSite

Description: The U.S. Dept. of Energy funded Frio Brine Pilot provided an opportunity to test borehole seismic monitoring techniques in a saline formation in southeast Texas. A relatively small amount of CO{sub 2} was injected (about 1600 tons) into a thin injection interval (about 6 m thick at 1500 m depth). Designed tests included time-lapse vertical seismic profile (VSP) and crosswell surveys which investigated the detectability of CO{sub 2} with surface-to-borehole and borehole-to-borehole measurement.
Date: June 1, 2006
Creator: Daley, Thomas M. & Korneev, Valeri A.
Partner: UNT Libraries Government Documents Department

Characterization of Mixed Wettability at Different Scales and Its Impact on Oil Recovery Efficiency

Description: The objectives of the this research project were to: (1) Quantify the pore scale mechanisms that determine the wettability state of a reservoir; (2) Study the effect of crude oil, brine and mineral compositions in the establishment of mixed wet states; (3) Clarify the effect of mixed-wettability on oil displacement efficiency in waterfloods; and (4) Develop a new tracer technique to measure wettability, fluid distributions, residual saturations and relative permeabilities.
Date: September 1, 2003
Creator: Sharma, Mukul M. & Hirasaki, George J.
Partner: UNT Libraries Government Documents Department

Intercomparison of numerical simulation codes for geologic disposal of CO2

Description: Numerical simulation codes were exercised on a suite of eight test problems that address CO2 disposal into geologic storage reservoirs, including depleted oil and gas reservoirs, and brine aquifers. Processes investigated include single- and multi-phase flow, gas diffusion, partitioning of CO2 into aqueous and oil phases, chemical interactions of CO2 with aqueous fluids and rock minerals, and mechanical changes due to changes in fluid pressures. Representation of fluid properties was also examined. In most cases results obtained from different simulation codes were in satisfactory agreement, providing confidence in the ability of current numerical simulation approaches to handle the physical and chemical processes that would be induced by CO2 disposal in geologic reservoirs. Some discrepancies were also identified and can be traced to differences in fluid property correlations, and space and time discretization.
Date: November 27, 2002
Creator: Pruess, Karsten; Garcia, Julio; Kovscek, Tony; Oldenburg, Curt; Rutqvist, Jonny; Steefel, Carl et al.
Partner: UNT Libraries Government Documents Department

Characterization of Mixed Wettablility at Different Scales and Its Impact on Oil Recovery Efficiency

Description: The objectives of the this research project were to: (1) Quantify the pore scale mechanisms that determine the wettability state of a reservoir; (2) Study the effect of crude oil, brine and mineral compositions in the establishment of mixed wet states; (3) Clarify the effect of mixed-wettability on oil displacement efficiency in waterfloods; and (4) Develop a new tracer technique to measure wettability, fluid distributions, residual saturations and relative permeabilities.
Date: August 31, 2003
Creator: Sharma, Mukul M. & Hirasaki, George J.
Partner: UNT Libraries Government Documents Department

Bioremediation Techniques of Oil Contaminated Soils in Ohio

Description: The objective of this project is to develop environmentally sound and cost-effective remediation techniques for crude oil contaminated soils. By providing a guidance manual to oil and gas operators, the Ohio Division of Oil and Gas regulatory authority hopes to reduce remediation costs while improving voluntary compliance with soil clean-up requirements. This shall be accomplished by conducting a series of field tests to define the optimum range for nutrient and organic enhancement to biologically remediate soils contaminated with brines and crude oil having a wide rage of viscosity.
Date: October 3, 1996
Creator: Hodges, David
Partner: UNT Libraries Government Documents Department

DESIGN AND DEVELOPMENT OF GAS-LIQUID CYLINDRICAL CYCLONE COMPACT SEPARATORS FOR THREE-PHASE FLOW

Description: The objective of this five-year project (October, 1997-September, 2002) is to expand the current research activities of Tulsa University Separation Technology Projects (TUSTP) to multiphase oil/water/gas separation. This project will be executed in two phases. Phase I (1997-2000) will focus on the investigations of the complex multiphase hydrodynamic flow behavior in a three-phase Gas-Liquid Cylindrical Cyclone (GLCC{copyright}) Separator. The activities of this phase will include the development of a mechanistic model, a computational fluid dynamics (CFD) simulator, and detailed experimentation on the three-phase GLCC{copyright}. The experimental and CFD simulation results will be suitably integrated with the mechanistic model. In Phase II (2000-2002), the developed GLCC{copyright} separator will be tested under high pressure and real crudes conditions. This is crucial for validating the GLCC{copyright} design for field application and facilitating easy and rapid technology deployment. Design criteria for industrial applications will be developed based on these results and will be incorporated into the mechanistic model by TUSTP. This report presents a brief overview of the activities and tasks accomplished during the first half year (October 1, 1999-March 31, 2000) of the budget period (October 1, 1999-September 30, 2000). The total tasks of the budget period are given initially, followed by the technical and scientific results achieved till date. The report concludes with a detailed description of the plans for the conduct of the project for the second half year (April 1, 2000-September 30, 2000) of the current budget period.
Date: April 28, 2000
Creator: Mohan, Dr. Ram S. & Shoham, Dr. Ovadia
Partner: UNT Libraries Government Documents Department

DILUTE SURFACTANT METHODS FOR CARBONATE FORMATIONS

Description: There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the only hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. We have acquired field oil and core samples and field brine compositions from Marathon. We have conducted preliminary adsorption and wettability studies. Addition of Na{sub 2}CO{sub 3} decreases anionic surfactant adsorption on calcite surface. Receding contact angles increase with surfactant adsorption. Plans for the next quarter include conducting adsorption, phase behavior and wettability studies.
Date: January 1, 2003
Creator: Mohanty, Kishore K.
Partner: UNT Libraries Government Documents Department

DESIGN AND DEVELOPMENT OF GAS-LIQUID CYLINDRICAL CYCLONE COMPACT SEPARATORS FOR THREE-PHASE FLOW

Description: The U.S. Department of Energy (DOE) has awarded a five-year (1997-2002) grant (Mohan and Shoham, DE-FG26-97BC15024, 1997) to The University of Tulsa, to develop compact multiphase separation components for 3-phase flow. The research activities of this project have been conducted through cost sharing by the member companies of the Tulsa University Separation Technology Projects (TUSTP) research consortium and the Oklahoma Center for the Advancement of Science and Technology (OCAST). As part of this project, several individual compact separation components have been developed for onshore and offshore applications. These include gas-liquid cylindrical cyclones (GLCC{copyright}), liquid-liquid cylindrical cyclones (LLCC{copyright}), and the gas-liquid-liquid cylindrical cyclones (GLLCC{copyright}). A detailed study has also been completed for the liquid-liquid hydrocyclones (LLHC). Appropriate control strategies have been developed for proper operation of the GLCC{copyright} and LLCC{copyright}. Testing of GLCC{copyright} at high pressure and real crude conditions for field applications is also completed. Limited studies have been conducted on flow conditioning devices to be used upstream of the compact separators for performance improvement. This report presents a brief overview of the activities and tasks accomplished during the 5-year project period, October 1, 1997-March 31, 2003 (including the no-cost extended period of 6 months). An executive summary is presented initially followed by the tasks of the 5-year budget periods. Then, detailed description of the experimental and modeling investigations are presented. Subsequently, the technical and scientific results of the activities of this project period are presented with some discussions. The findings of this investigation are summarized in the ''Conclusions'' section, followed by relevant references. The publications resulting from this study in the form of MS Theses, Ph.D. Dissertation, Journal Papers and Conference Presentations are provided at the end of this report.
Date: June 25, 2003
Creator: Mohan, Dr. Ram S. & Shoham, Dr. Ovadia
Partner: UNT Libraries Government Documents Department

Prediction of dissolved actinide concentrations in concentrated electrolyte solutions: a conceptual model and model results for the Waste Isolation Pilot Plant (WIPP)

Description: The conceptual model for WIPP dissolved concentrations is a description of the complex natural and artificial chemical conditions expected to influence dissolved actinide concentrations in the repository. By a set of physical and chemical assumptions regarding chemical kinetics, sorption substrates, and waste-brine interactions, the system was simplified to be amenable to mathematical description. The analysis indicated that an equilibrium thermodynamic model for describing actinide solubilities in brines would be tractable and scientifically supportable. This paper summarizes the conceptualization and modeling approach and the computational results as used in the WIPP application for certification of compliance with relevant regulations for nuclear waste repositories. The WIPP site contains complex natural brines ranging from sea water to 10x more concentrated than sea water. Data bases for predicting solubility of Am(III) (as well as Pu(III) and Nd(III)), Th(IV), and Np(V) in these brines under potential repository conditions have been developed, focusing on chemical interactions with Na, K, Mg, Cl, SO{sub 4}, and CO{sub 3} ions, and the organic acid anions acetate, citrate, EDTA, and oxalate. The laboratory and modeling effort augmented the Harvie et al. parameterization of the Pitzer activity coefficient model so that it could be applied to the actinides and oxidation states important to the WIPP system.
Date: October 25, 1996
Creator: Novak, C.F.; Moore, R.C. & Bynum, R.V.
Partner: UNT Libraries Government Documents Department

Salt effects on isotope partitioning and their geochemical implications: An overview

Description: Essential to the use of stable isotopes as natural tracers and geothermometers is the knowledge of equilibrium isotope partitioning between different phases and species, which is usually a function of temperature only. The one exception known to date is oxygen and hydrogen isotope fractionation between liquid water and other phases (steam, gases, minerals), which changes upon the addition of salts to water, i.e., the isotope salt salt effect. Our knowledge of this effect, the difference between activity and composition (a-X) of isotopic water molecules in salt solutions, is very limited and controversial, especially at elevated temperatures. For the last several years, we have been conducting a detailed, systematic experimental study at Oak Ridge National Laboratory to determine the isotope salt effects from room temperature to elevated temperatures (currently to 500{degree}C). From this effort, a simple, coherent picture of the isotope salt effect is emerging, that differs markedly from the complex results reported in the literature. In this communication, we present an overview on the isotope salt effect, obtained chiefly from our study. Observed isotope salt effects in salt solutions are significant even at elevated temperatures. The importance and implications of the isotope salt effect for isotopic studies of brine-dominated systems are also discussed in general terms.
Date: January 1, 1996
Creator: Horita, J.; Cole, D.R. & Fortier, S.M.
Partner: UNT Libraries Government Documents Department

Wetting behavior of selected crude oil/brine/rock systems

Description: Of the many methods of characterizing wettability of a porous medium, the most commonly used are the Amott test and the USBM test. The Amott test does not discriminate adequately between systems that give high values of wettability index to water and are collectively described as very strongly water-wet. The USBM test does not recognize systems that achieve residual oil saturation by spontaneous imbibition. For such systems, and for any systems that exhibit significant spontaneous imbibition, measurements of imbibition rate provide a useful characterization of wettability. Methods of interpreting spontaneous imbibition data are reviewed and a new method of quantifying wettability from rate of imbibition is proposed. Capillary pressure is the driving force in spontaneous imbibition. The area under an imbibition curve is closely related to the work of displacement that results from decrease in surface free energy. Imbibition rate data can be correlated to allow for differences in interracial tension, viscosities, pore structure, and sample size. Wettability, the remaining key factor in determining the capillary driving force and the related imbibition rate, then largely determines the differences in saturation vs. scaled time curves. These curves are used to obtain pseudo imbibition capillary pressure curves; a wettability index based on relative areas under these curves is defined as the relative pseudo work of imbibition. The method is applied for two crude oil/brine/rock systems. Comparison of the method with the Amott wettability index is made for different wettability states given by differences in aging of cores with crude oil. Correlations of wettability indices with waterflood recoveries are presented.
Date: April 1, 1997
Partner: UNT Libraries Government Documents Department

Laboratory evaluation of colloidal actinide transport at the Waste Isolation Pilot Plant (WIPP): 1. crushed-dolomite column flow...

Description: Colloid-facilitated transport of Pu, Am, U, Th, and Np has been recognized as a potentially important phenomenon affecting the performance of the Waste Isolation Pilot Plant (WIPP) facility being developed for safe disposal of transuranic radioactive waste. In a human intrusion scenario, actinide-bearing colloidal particles may be released from the repository and be transported by brines (approximately 0.8 to 3 molal ionic strength) through the Culebra, a thin fractured microcrystalline (mean grain size 2 micrometers) dolomite aquifer overlying the repository. Transport experiments were conducted using sieved, uniformly packed crushed Culebra rock or nonporous dolomite cleavage rhombohedra. Experiments with mineral fragments and fixed and live WIPP-relevant bacteria cultures showed significant levels of retardation due to physical filtration effects. Humic substances were not attenuated by the Culebra dolomite. Comparison of elution curves of latex microspheres in columns prepared with microcrystalline rock and nonporous rock showed minimal effect of Culebra micropores on colloid transport. These data form part of the basis to parameterize numerical codes being used to evaluate the performance of the WIPP.
Date: December 31, 1996
Creator: Yelton, W.G.; Behl, Y.K.; Kelly, J.W.; Dunn, M.; Gillow, J.B.; Francis, A.J. et al.
Partner: UNT Libraries Government Documents Department

Evaluation of Reservoir Wettability and its Effect on Oil Recovery.

Description: This project has three main goals. The first is to achieve improved understanding of the surface and interfacial properties of crude oils and their interactions with mineral surfaces. The second goal is to apply the results of surface studies to improved predictions of oil production in laboratory experiments. Finally, we aim to use the results of this research to recommend ways to improve oil recovery by waterflooding. In order to achieve these goals, the mechanisms of wetting alteration must be explained. We propose a methodology for studying those mechanisms on mineral surfaces, then applying the results to prediction and observation of wetting alteration in porous media. Improved understanding of the underlying mechanisms will show when and how wettability in the reservoir can be altered and under what circumstances that alteration would be beneficial in terms of increased production of oil. Crude Oil/Brine/Solid Interactions The interactions between crude oils, brines, and solid surfaces have been studied using a variety of core materials as well as in two-dimensional micromodels of interconnecting pores and throats. In the work reported this quarter, these same interactions have been applied to create mixed-wet conditions in a very simple model porous material, namely square glass tubes which have the advantage of permitting dual occupancy by both wetting and nonwetting phases simultaneously. The interactions between crude oil samples from Prudhoe Bay have been studied on a variety of surfaces. Figure 1 outlines the regions of stable and unstable brine compositions with A-93, a sample from Prudhoe Bay, and glass surfaces. A brine with pH 8 and 1 M concentration of NaCl produces a stable water film between glass and A-93 crude oil. If the brine has pH 4 and 0.01M NaCl, thin films of water are unstable and oil contacts the glass. Between these extremes is a wide ...
Date: October 1, 1997
Creator: Buckley, J.S.
Partner: UNT Libraries Government Documents Department

History of geophysical studies at the Waste Isolation Pilot Plant (WIPP), southeastern New Mexico

Description: A variety of geophysical methods including the spectrum of seismic, electrical, electromagnetic and potential field techniques have supported characterization, monitoring and experimental studies at the Waste Isolation Pilot Plant (WIPP). The geophysical studies have provided significant understanding of the nature of site deformation, tectonics and stability. Geophysical methods have delineated possible brine reservoirs beneath the underground facility and have defined the disturbed rock zone that forms around underground excavations. The role of geophysics in the WIPP project has evolved with the project. The early uses were for site characterization to satisfy site selection criteria or factors. As the regulatory framework for WIPP grew since 1980, the geophysics program supported experimental and field programs such as Salado hydrogeology and underground room systems and excavations. In summary, the major types of issues that geophysical studies addressed for WIPP are: Site Characterization; Castile Brine Reservoirs; Rustler/Dewey Lake Hydrogeology; Salado Hydrogeology; and Excavation Effects. The nature of geophysics programs for WIPP has been to support investigation rather than being the principal investigation itself. The geophysics program has been used to define conceptual models (e.g., the Disturbed Rock Zone-DRZ) or to test conceptual models (e.g., high transmissivity zones in the Rustler Formation). The geophysics program primarily supported larger characterization and experimental programs. Funding was not available for the complete documentation and interpretation. Therefore, a great deal of the geophysics survey information resides in contractor reports.
Date: March 5, 1997
Creator: Borns, D.J.
Partner: UNT Libraries Government Documents Department

Stress corrosion cracking of Fe-Ni-Cr-Mo, Ni-Cr-Mo and Ti alloys in 90{degrees}C acidic brince

Description: Susceptibility to stress corrosion cracking (SCC) of candidate materials for the inner container of the multi-barrier nuclear waste package was evaluated by using wedge-loaded precracked double- cantilever-beam (DCB) specimens in deaerated acidic brine (pH at 2.70) at 90{degrees}C. Materials tested include Alloys 825, G-30, C-4, 625 and C-22; and Ti Grade- 12. Duplicate specimen of each material was loaded at different initial stress intensity factor (K) values ranging between 23 and 46 ksi/in. Both metallography and compliance method were used to determine the final crack length. The final stress intensity for SCC (K{sup ISCC}) was computed from the measured final wedge load and the average crack length. The results indicate that in general, the final crack length measured by metallography and compliance was very close to each other, thus, providing very similar K{sup ISCC} values. While tests are still ongoing, the preliminary results suggest that, compared to other five alloys tested, Alloy 825 may exhibit the maximum tendency to SCC.
Date: November 1, 1997
Creator: Roy, A.K.; Fleming, D.L. & Lum, B.Y.
Partner: UNT Libraries Government Documents Department

WETTING BEHAVIOR OF SELECTED CRUDE OIL/BRINE/ROCK SYSTEMS

Description: The effect of aging and displacement temperatures, and brine and oil composition on wettability and the recovery of crude oil by spontaneous imbibition and waterflooding has been investigated. This study is based on displacement tests in Berea Sandstone using three distinctly different crude oils and three reservoir brines. Brine concentration was varied by changing the concentration of total dissolved solids of the synthetic brine in proportion to give brine of twice, one tenth, and one hundredth of the reservoir brine concentration. Aging and displacement temperatures were varied independently. For all crude oils, water-wetness and oil recovery increased with increase in displacement temperature. Tests on the effect of brine concentration showed that salinity of the connate and invading brines can have a major influence on wettability and oil recovery at reservoir temperature. Oil recovery increased over that for the reservoir brine with dilution of both the initial (connate) and invading brine or dilution of either. Removal of light components from the crude oil resulted in increased water-wetness. Addition of alkanes to the crude oil reduced the water-wetness, and increased oil recovery. Relationships between waterflood recovery and wettability are summarized.
Date: April 1, 1997
Creator: Tang, G.Q. & Morrow, N.R.
Partner: UNT Libraries Government Documents Department

Geochemistry of Aluminum in High Temperature Brines

Description: The objective ofthis research is to provide quantitative data on the equilibrium and thermodynamic properties of aluminum minerals required to model changes in permeability and brine chemistry associated with fluid/rock interactions in the recharge, reservoir, and discharge zones of active geothermal systems. This requires a precise knowledge of the thermodynamics and speciation of aluminum in aqueous brines, spanning the temperature and fluid composition rangesencountered in active systems. The empirical and semi-empirical treatments of the solubility/hydrolysis experimental results on single aluminum mineral phases form the basis for the ultimate investigation of the behavior of complex aluminosilicate minerals. The principal objective in FY 1998 was to complete the solubility measurements on boehmite (AIOOH) inNaC1 media( 1 .O and 5.0 molal ionic strength, IOO-250°C). However, additional measurements were also made on boehmite solubility in pure NaOH solutions in order to bolster the database for fitting in-house isopiestic data on this system. Preliminary kinetic Measurements of the dissolution/precipitation of boehmite was also carried out, although these were also not planned in the earlier objective. The 1999 objectives are to incorporate these treatments into existing codes used by the geothermal industry to predict the chemistry ofthe reservoirs; these calculations will be tested for reliability against our laboratory results and field observations. Moreover, based on the success of the experimental methods developed in this program, we intend to use our unique high temperature pH easurement capabilities to make kinetic and equilibrium studies of pH-dependent aluminosilicate transformation reactions and other pH-dependent heterogeneous reactions.
Date: May 18, 1999
Creator: Benezeth, P.; Palmer, D. A. & Wesolowski, D. J.
Partner: UNT Libraries Government Documents Department

Design and Development of Gas-Liquid Cylindrical Cyclone Compact Separators for Three-Phase Flow

Description: The objective of this five-year project (October 1997 - September 2002) was to expand the current research activities of Tulsa University Separation Technology Projects (TUSTP) to multiphase oil/water/gas separation. This project was executed in two phases. Phase I (1997 - 2000) focused on the investigations of the complex multiphase hydrodynamic flow behavior in a three-phase Gas-Liquid Cylindrical Cyclone (GLCC) Separator. The activities of this phase included the development of a mechanistic model, a computational fluid dynamics (CFD) simulator, and detailed experimentation on the three-phase GLCC. The experimental and CFD simulation results will be suitably integrated with the mechanistic model. In Phase II (2000 - 2002), the developed GLCC separator will be tested under high pressure and real crude conditions. This is crucial for validating the GLCC design for field application and facilitating easy and rapid technology deployment. Design criteria for industrial applications will be developed based on these results and will be incorporated into the mechanistic model by TUSTP.
Date: January 18, 2001
Creator: Mohan, R.S. & Shoham, O.
Partner: UNT Libraries Government Documents Department

Electrochemical and metallographic evaluation of alloys C-22 and 625

Description: Electrochemical cyclic potentiodynamic polarization (CPP) experiments were performed on Alloys C-22 and 625 to evaluate their susceptibility to localized corrosion in acidic brines of various salt content at 90{degrees}C. The microstructures of both tested and untested specimen`s were evaluated by optical microscopy. This paper presents the results showing the effect of chloride ion concentration on the pitting and crevice corrosion behavior of these alloys, and the relationship of the observed microstructures to the resulting surface degradation modes.
Date: May 1, 1997
Creator: Roy, A. K.; Fleming, D. L. & Lum, B. Y.
Partner: UNT Libraries Government Documents Department