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North Texas Star (Mineral Wells, Tex.), January 2009
Monthly newspaper from Mineral Wells, Texas that includes history and travel stories along with advertising.
Date:
January 1, 2009
Creator:
May, David
Object Type:
Newspaper
System:
The Portal to Texas History
North Texas Star (Mineral Wells, Tex.), March 2009
Monthly newspaper from Mineral Wells, Texas that includes history and travel stories along with advertising.
Date:
March 1, 2009
Creator:
May, David
Object Type:
Newspaper
System:
The Portal to Texas History
North Texas Star (Mineral Wells, Tex.), February 2009
Monthly newspaper from Mineral Wells, Texas that includes history and travel stories along with advertising.
Date:
February 1, 2009
Creator:
May, David
Object Type:
Newspaper
System:
The Portal to Texas History
North Texas Star (Mineral Wells, Tex.), April 2009
Monthly newspaper from Mineral Wells, Texas that includes history and travel stories along with advertising.
Date:
April 1, 2009
Creator:
May, David
Object Type:
Newspaper
System:
The Portal to Texas History
Mineral transformation and biomass accumulation associated with uranium bioremediation at Rifle, Colorado
Injection of organic carbon into the subsurface as an electron donor for bioremediation of redox-sensitive contaminants like uranium often leads to mineral transformation and biomass accumulation, both of which can alter the flow field and potentially bioremediation efficacy. This work combines reactive transport modeling with a column experiment and field measurements to understand the biogeochemical processes and to quantify the biomass and mineral transformation/accumulation during a bioremediation experiment at a uranium contaminated site near Rifle, Colorado. We use the reactive transport model CrunchFlow to explicitly simulate microbial community dynamics of iron and sulfate reducers, and their impacts on reaction rates. The column experiment shows clear evidence of mineral precipitation, primarily in the form of calcite and iron monosulfide. At the field scale, reactive transport simulations suggest that the biogeochemical reactions occur mostly close to the injection wells where acetate concentrations are highest, with mineral precipitate and biomass accumulation reaching as high as 1.5% of the pore space. This work shows that reactive transport modeling coupled with field data can be an effective tool for quantitative estimation of mineral transformation and biomass accumulation, thus improving the design of bioremediation strategies.
Date:
April 20, 2009
Creator:
Li, L.; Steefel, C. I.; Williams, K. H.; Wilkins, M. J. & Hubbard, S. S.
Object Type:
Article
System:
The UNT Digital Library
Mountaintop Mining: Background on Current Controversies
Mountaintop removal mining involves removing the top of a mountain in order to recover the coal seams contained there. This practice occurs in several Appalachian states. It creates an immense quantity of excess spoil (dirt and rock that previously composed the mountaintop), which is typically placed in valley fills on the sides of the former mountains, burying streams that flow through the valleys. Critics say that, as a result of valley fills, stream water quality and the aquatic and wildlife habitat that streams support are destroyed by tons of rocks and dirt. The mining industry argues that mountaintop mining is essential to conducting surface coal mining in the Appalachian region and that surface coal mining would not be economically feasible there if producers were restricted from using valleys for the disposal of mining overburden. Mountaintop mining is regulated under several laws, including the Clean Water Act and the Surface Mining Control and Reclamation Act. This report provides background on regulatory requirements, controversies, and legal challenges to regulation of mountaintop mining. Congressional attention to these issues, including legislation that would restrict the practice (H.R. 1310, the Clean Water Protection Act, and S. 696, the Appalachia Restoration Act), also is discussed.
Date:
April 20, 2009
Creator:
Copeland, Claudia
Object Type:
Report
System:
The UNT Digital Library
Effects of physical and geochemical heterogeneities on mineral transformation and biomass accumulation during uranium bioremediation at Rifle, Colorado
None
Date:
June 15, 2009
Creator:
Li, Li; Steefel, C. I.; Hubbard, S. S.; Kowalsky, M. B. & Englert, A.
Object Type:
Article
System:
The UNT Digital Library
Numerical simulation study of silica and calcite dissolution around a geothermal well by injecting high pH solutions with chelating agent.
Dissolution of silica, silicate, and calcite minerals in the presence of a chelating agent (NTA) at a high pH has been successfully performed in the laboratory using a high-temperature flow reactor. The mineral dissolution and porosity enhancement in the laboratory experiment has been reproduced by reactive transport simulation using TOUGHREACT. The chemical stimulation method has been applied by numerical modeling to a field geothermal injection well system, to investigate its effectiveness. Parameters from the quartz monzodiorite unit at the Enhanced Geothermal System (EGS) site at Desert Peak (Nevada) were used. Results indicate that the injection of a high pH chelating solution results in dissolution of both calcite and plagioclase minerals, and avoids precipitation of calcite at high temperature conditions. Consequently reservoir porosity and permeability can be enhanced especially near the injection well.
Date:
February 1, 2009
Creator:
Xu, Tianfu; Rose, Peter; Fayer, Scott & Pruess, Karsten
Object Type:
Article
System:
The UNT Digital Library
Mineral Revenues: MMS Could Do More to Improve the Accuracy of Key Data Used to Collect and Verify Oil and Gas Royalties
A letter report issued by the Government Accountability Office with an abstract that begins "In fiscal year 2008, the Department of Interior's Minerals Management Service (MMS) collected over $12 billion in royalties from oil and gas production from federal lands and waters. Companies that produce this oil and gas self-report to MMS data on the amount of oil and gas they produced and sold, the value of this production, and the amount of royalties owed. Since 2004, GAO has noted systemic problems with these data and recommended improvements. GAO is providing: (1) a descriptive update on MMS's key efforts to improve the accuracy of oil and gas royalty data; (2) our assessment of the completeness and reasonableness of fiscal years 2006 and 2007 oil and gas royalty data--the latest data available; and (3) factors identified by oil and gas companies that affect their ability to accurately report royalties owed to the federal government."
Date:
July 15, 2009
Creator:
United States. Government Accountability Office.
Object Type:
Report
System:
The UNT Digital Library
Silurian "Clinton" Sandstone Reservoir Characterization for Evaluation of CO2-EOR Potential in the East Canton Oil Field, Ohio
The purpose of this study was to evaluate the efficacy of using CO2-enhanced oil recovery (EOR) in the East Canton oil field (ECOF). Discovered in 1947, the ECOF in northeastern Ohio has produced approximately 95 million barrels (MMbbl) of oil from the Silurian 'Clinton' sandstone. The original oil-in-place (OOIP) for this field was approximately 1.5 billion bbl and this study estimates by modeling known reservoir parameters, that between 76 and 279 MMbbl of additional oil could be produced through secondary recovery in this field, depending on the fluid and formation response to CO2 injection. A CO2 cyclic test ('Huff-n-Puff') was conducted on a well in Stark County to test the injectivity in a 'Clinton'-producing oil well in the ECOF and estimate the dispersion or potential breakthrough of the CO2 to surrounding wells. Eighty-one tons of CO2 (1.39 MMCF) were injected over a 20-hour period, after which the well was shut in for a 32-day 'soak' period before production was resumed. Results demonstrated injection rates of 1.67 MMCF of gas per day, which was much higher than anticipated and no CO2 was detected in gas samples taken from eight immediately offsetting observation wells. All data collected during this test was analyzed, …
Date:
December 30, 2009
Creator:
Riley, Ronald; Wicks, John & Perry, Christopher
Object Type:
Report
System:
The UNT Digital Library
On modeling of chemical stimulation of an enhanced geothermal system using a high pH solution with chelating agent
Dissolution of silica and calcite in the presence of a chelating agent (NTA) at a high pH was successfully demonstrated in laboratory experiments using a high-temperature flow reactor. (Note that the term 'silica' used here includes amorphous silica, quartz, and silicate glass bead). The mineral dissolution and associated porosity enhancement in the experiments were reproduced by reactive transport modeling using TOUGHREACT. The chemical stimulation method was applied by numerical modeling to a field geothermal injection well system to investigate its effectiveness. Parameters applicable to the quartz monzodiorite unit at the Enhanced Geothermal Systems (EGS) site at Desert Peak (Nevada) were used. Results indicate that the injection of a high pH chelating solution results in dissolution of both calcite and plagioclase, while avoiding precipitation of calcite at high temperature conditions. Consequently reservoir porosity and permeability can be enhanced especially near the injection well. Injection at a lower temperature of 120 C (over 160 C in the base-case) results in a porosity increase that is smaller close to the injection point, but extends to a larger radial distance. A slower kinetic rate results in less aggressive mineral dissolution close to the injection point and larger extent along the flow path, which is …
Date:
May 1, 2009
Creator:
Xu, T.; Rose, P.; Fayer, S. & Pruess, K.
Object Type:
Article
System:
The UNT Digital Library
Using hyperspectral plant signatures for CO2 leak detection during the 2008 ZERT CO2 sequestration field experiment in Bozeman, Montana
Hyperspectral plant signatures can be used as a short-term, as well as long-term (100-yr timescale) monitoring technique to verify that CO2 sequestration fields have not been compromised. An influx of CO2 gas into the soil can stress vegetation, which causes changes in the visible to nearinfrared reflectance spectral signature of the vegetation. For 29 days, beginning on July 9th, 2008, pure carbon dioxide gas was released through a 100-meter long horizontal injection well, at a flow rate of 300 kg/day. Spectral signatures were recorded almost daily from an unmown patch of plants over the injection with a ''FieldSpec Pro'' spectrometer by Analytical Spectral Devices, Inc. Measurements were taken both inside and outside of the CO2 leak zone to normalize observations for other environmental factors affecting the plants.
Date:
November 1, 2009
Creator:
Male, E. J.; Pickles, W. L.; Silver, E. A.; Hoffmann, G. D.; Lewicki, J.; Apple, M. et al.
Object Type:
Article
System:
The UNT Digital Library
Numerical simulation to study the feasibility of using CO2 as a stimulation agent for enhanced geothermal systems
A major concern in the development of enhanced geothermal systems (EGS) is achieving and maintaining adequate injectivity, while avoiding the development of preferential short-circuiting flow paths such as those caused by thermally-induced stress cracking. Past researches have tended to focus primarily on thermal and hydraulic stimulation. Recent studies suggest that chemical stimulation may improve the performance of EGS reservoirs. Geothermal injection wells are often drilled into formations containing reactive minerals such as calcite. Injecting aqueous chemical agents such as mineral acids, could be effective for mineral dissolution and porosity enhancement at distances of several meters around a well. An alternative to treatment with strong acids is the use of supercritical (SC) CO{sub 2} as stimulation agent for an aqueous-based EGS. Reactive transport modeling is used to investigate the effectiveness of this method. We used the thermal condition and mineralogical composition from a well of Desert Peak EGS site, to examine ways in which mixtures of water and CO{sub 2} can be injected to enhance porosity.
Date:
November 15, 2009
Creator:
Xu, T.; Zhang, W. & Pruess, K.
Object Type:
Article
System:
The UNT Digital Library
300 Area Uranium Stabilization Through Polyphosphate Injection: Final Report
The objective of the treatability test was to evaluate the efficacy of using polyphosphate injections to treat uranium-contaminated groundwater in situ. A test site consisting of an injection well and 15 monitoring wells was installed in the 300 Area near the process trenches that had previously received uranium-bearing effluents. This report summarizes the work on the polyphosphate injection project, including bench-scale laboratory studies, a field injection test, and the subsequent analysis and interpretation of the results. Previous laboratory tests have demonstrated that when a soluble form of polyphosphate is injected into uranium-bearing saturated porous media, immobilization of uranium occurs due to formation of an insoluble uranyl phosphate, autunite [Ca(UO2)2(PO4)2•nH2O]. These tests were conducted at conditions expected for the aquifer and used Hanford soils and groundwater containing very low concentrations of uranium (10-6 M). Because autunite sequesters uranium in the oxidized form U(VI) rather than forcing reduction to U(IV), the possibility of re-oxidation and subsequent re-mobilization is negated. Extensive testing demonstrated the very low solubility and slow dissolution kinetics of autunite. In addition to autunite, excess phosphorous may result in apatite mineral formation, which provides a long-term source of treatment capacity. Phosphate arrival response data indicate that, under site conditions, the …
Date:
June 30, 2009
Creator:
Vermeul, Vincent R.; Bjornstad, Bruce N.; Fritz, Brad G.; Fruchter, Jonathan S.; Mackley, Rob D.; Newcomer, Darrell R. et al.
Object Type:
Report
System:
The UNT Digital Library
81st Texas Legislature, Regular Session, House Bill 2259, Chapter 442
Bill introduced by the Texas House of Representatives relating to the plugging of certain inactive oil or gas wells and to standards for electrical power lines serving certain oil and gas facilities.
Date:
June 19, 2009
Creator:
Texas. Legislature. House of Representatives.
Object Type:
Legislative Document
System:
The Portal to Texas History
An Evaluation of the Feasibility of Combining Carbon Dioxide Flooding Technologies with Microbial Enhanced Oil Recovery Technologies in Order To Sequester Carbon Dioxide
The need for more energy as our population grows results in an increase in the amount of CO2 introduced into the atmosphere. The effect of this introduction is currently debated intensely as to the severity of the effect of this. The bjective of this investigation was to determine if the production of more energy (i.e. petroleum) and the sequestration of CO2 could be coupled into one process. Carbon dioxide flooding is a well-established technique that introduces Compressed CO2 into a subsurface oil-bearing formation to aide in liquefying harder to extract petroleum and enhancing its mobility towards the production wells.
Date:
August 19, 2009
Creator:
French, Todd; Brown, Lew; Hernandez, Rafael; Green, Magan; Prewitt, Lynn & Coggins, Terry
Object Type:
Report
System:
The UNT Digital Library
Precipitate Formation Potential of Resin Regeneration Effluent in the 100-HR-3 Operable Unit
Calculations performed as part of this study indicate that injection of treated groundwater containing treated regenerant solution has a high potential for precipitate formation that could lead to plugging of formation porosity surrounding the injection well. In the worst case scenario, substantial plugging could occur within a year of the initiation of injection. Some uncertainty is associated with respect to this conclusion. The uncertainty results from the fact that equilibrium with the most stable mineral assemblage cannot always be assumed and that slow precipitation rates could occur and reliable estimates of precipitation kinetics under Hanford aquifer conditions are not available. It is recommended that the potential of calcium phosphate precipitation be investigated further using a combination of laboratory and field investigations.
Date:
October 9, 2009
Creator:
Cantrell, Kirk J.
Object Type:
Report
System:
The UNT Digital Library
Preliminary simulations of planned experiments to study the impact of trace gases on the capacity of the Weyburn-Midale field to store carbon dioxide
The CO{sub 2} stream injecting into the Weyburn-Midale field can be generally classified as a reducing stream with residual H{sub 2}S and low-molecular weight hydrocarbons. The composition of the CO{sub 2} gas stream from the Dakota Gasification Company is reported to be 95% CO{sub 2}, 4% hydrocarbons, and 1% H{sub 2}S by volume (Huxley 2006). In addition to the H{sub 2}S introduced at the injection wells, significant concentrations of H{sub 2}S are thought to have been produced in-situ by sulfate reducing bacteria from previous water floods for enhanced oil production. Produced gas compositions range in H{sub 2}S concentrations from 1 to 6 volume percent. The produced gas, including the trace impurities, is re-injected into the field. Although there is no evidence for inorganic reduction of SO{sub 4}{sup 2-} to H{sub 2}S at the Weyburn-Midale field, Sitchler and Kazuba (2009) suggest that SO{sub 4}{sup 2-} can be inorganically reduced to elemental sulfur in highly reducing environments based on a natural analog study of the Madison Formation in Wyoming. They propose that elevated concentrations of CO{sub 2} dissolve anhydrite to produce the sulfate that is then reduced. Oxidizing CO{sub 2} streams with residual O{sub 2} and SO{sub 2} typical of streams captured …
Date:
November 13, 2009
Creator:
Carroll, S & Hao, Y
Object Type:
Report
System:
The UNT Digital Library
Changes in the chemistry of shallow groundwater related to the 2008 injection of CO2 at the ZERT Field Site, Bozeman, Montana
Approximately 300 kg/day of food-grade CO2 was injected through a perforated pipe placed horizontally 2-2.3 m deep during July 9-August 7, 2008 at the MSU-ZERT field test to evaluate atmospheric and near-surface monitoring and detection techniques applicable to the subsurface storage and potential leakage of CO2. As part of this multidisciplinary research project, 80 samples of water were collected from 10 shallow monitoring wells (1.5 or 3.0 m deep) installed 1-6 m from the injection pipe, at the southwestern end of the slotted section (zone VI), and from two distant monitoring wells. The samples were collected before, during and following CO2 injection. The main objective of study was to investigate changes in the concentrations of major, minor and trace inorganic and organic compounds during and following CO2 injection.
Date:
September 1, 2009
Creator:
Kharaka, Y. K.; Thordsen, T. T.; Kakouros, E.; Ambats, G.; Herkelrath, W. N.; Birkholzer, J. T. et al.
Object Type:
Article
System:
The UNT Digital Library
Crosscutting Technology Development at the Center for Advanced Separation Technologies
The U.S. is the largest producer of mining products in the world. In 2003, U.S. mining operations produced $57 billion worth of raw materials that contributed a total of $564 billion to the nation's wealth. Despite these contributions, the mining industry has not been well supported with research and development funds as compared to mining industries in other countries. To overcome this problem, the Center for Advanced Separation Technologies (CAST) was established to develop technologies that can be used by the U.S. mining industry to create new products, reduce production costs, and meet environmental regulations. Originally set up by Virginia Tech and West Virginia University, this endeavor has been expanded into a seven-university consortium -- Virginia Tech, West Virginia University, University of Kentucky, University of Utah, Montana Tech, New Mexico Tech and University of Nevada, Reno - that is supported through U.S. DOE Cooperative Agreement No. DE-FC26-02NT41607: Crosscutting Technology Development at the Center for Advanced Separation Technologies. Much of the research to be conducted with Cooperative Agreement funds will be longer-term, high-risk, basic research and will be carried out in five broad areas: (1) Solid-solid separation; (2) Solid-liquid separation; (3) Chemical/biological extraction; (4) Modeling and control; and (5) Environmental control. …
Date:
October 31, 2009
Creator:
Hull, Christopher
Object Type:
Report
System:
The UNT Digital Library
Investigation of CO2 plume behavior for a large-scale pilot test of geologic carbon storage in a saline formation
The hydrodynamic behavior of carbon dioxide (CO{sub 2}) injected into a deep saline formation is investigated, focusing on trapping mechanisms that lead to CO{sub 2} plume stabilization. A numerical model of the subsurface at a proposed power plant with CO{sub 2} capture is developed to simulate a planned pilot test, in which 1,000,000 metric tons of CO{sub 2} is injected over a four-year period, and the subsequent evolution of the CO{sub 2} plume for hundreds of years. Key measures are plume migration distance and the time evolution of the partitioning of CO{sub 2} between dissolved, immobile free-phase, and mobile free-phase forms. Model results indicate that the injected CO{sub 2} plume is effectively immobilized at 25 years. At that time, 38% of the CO{sub 2} is in dissolved form, 59% is immobile free phase, and 3% is mobile free phase. The plume footprint is roughly elliptical, and extends much farther up-dip of the injection well than down-dip. The pressure increase extends far beyond the plume footprint, but the pressure response decreases rapidly with distance from the injection well, and decays rapidly in time once injection ceases. Sensitivity studies that were carried out to investigate the effect of poorly constrained model parameters …
Date:
April 1, 2009
Creator:
Doughty, C.
Object Type:
Article
System:
The UNT Digital Library
Formation dry-out from CO2 injection into saline aquifers: Part 1, Effects of solids precipitation and their mitigation
Injection of CO{sub 2} into saline aquifers may cause formation dry-out and precipitation of salt near the injection well, which may reduce formation porosity, permeability, and injectivity. This paper uses numerical simulation to explore the role of different processes and parameters in the salt precipitation process and to examine injection strategies that could mitigate the effects. The main physical mechanisms affecting the dry-out and salt precipitation process include (1) displacement of brine away from the injection well by injected CO{sub 2}, (2) dissolution (evaporation) of brine into the flowing CO{sub 2} stream, (3) upflow of CO{sub 2} due to gravity effects (buoyancy), (4) backflow of brine toward the injection point due to capillary pressure gradients that oppose the pressure gradient in the CO{sub 2}-rich ('gas') phase, and (5) molecular diffusion of dissolved salt. The different mechanisms operate on a range of spatial scales. CO{sub 2} injection at constant rate into a homogeneous reservoir with uniform initial conditions is simulated in 1-D radial geometry, to resolve multiscale processes by taking advantage of the similarity property, i.e., the evolution of system conditions as a function of radial distance R and time t depends only on the similarity variable R{sup 2}/t. Simulations in …
Date:
February 1, 2009
Creator:
Pruess, Karsten & Muller, Nadja
Object Type:
Article
System:
The UNT Digital Library
Evaluation of Oil and Gas Platforms on the Louisiana Continental Shelf for Organisms with Biotechnology Potential
This is a study that looks at the potential biotechnology application of organisms attached to offshore platforms and wells.
Date:
November 2009
Creator:
Louisiana State University (Baton Rouge, La.). Coastal Studies Institute.
Object Type:
Text
System:
The UNT Digital Library
Leveraging Regional Exploration to Develop Geologic Framework for CO2 Storage in Deep Formations in Midwestern United States
Obtaining subsurface data for developing a regional framework for geologic storage of CO{sub 2} can require drilling and characterization in a large number of deep wells, especially in areas with limited pre-existing data. One approach for achieving this objective, without the prohibitive costs of drilling costly standalone test wells, is to collaborate with the oil and gas drilling efforts in a piggyback approach that can provide substantial cost savings and help fill data gaps in areas that may not otherwise get characterized. This leveraging with oil/gas drilling also mitigates some of the risk involved in standalone wells. This collaborative approach has been used for characterizing in a number of locations in the midwestern USA between 2005 and 2009 with funding from U.S. Department of Energy's National Energy Technology Laboratory (DOE award: DE-FC26-05NT42434) and in-kind contributions from a number of oil and gas operators. The results are presented in this final technical report. In addition to data collected under current award, selected data from related projects such as the Midwestern Regional Carbon Sequestration Partnership (MRCSP), the Ohio River Valley CO{sub 2} storage project at and near the Mountaineer Plant, and the drilling of the Ohio Stratigraphic well in Eastern Ohio are …
Date:
September 30, 2009
Creator:
Gupta, Neeraj
Object Type:
Report
System:
The UNT Digital Library