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Integrated Field, Laboratory, and Modeling Studies to Determine the Effects of Linked Microbial and Physical Spatial Heterogeneity on Engineered Vadose Zone Bioremediation (open access)

Integrated Field, Laboratory, and Modeling Studies to Determine the Effects of Linked Microbial and Physical Spatial Heterogeneity on Engineered Vadose Zone Bioremediation

Executive Summary - While numerous techniques exist for remediation of contaminant plumes in groundwater or near the soil surface, remediation methods in the deep vadose zone are less established due to complex transport dynamics and sparse microbial populations. There is a lack of knowledge on how physical and hydrologic features of the vadose zone control microbial growth and colonization in response to nutrient delivery during bioremediation. Yet pollution in the vadose zone poses a serious threat to the groundwater resources lying deeper in the sediment. While the contaminants may be slowly degraded by native microbial communities, microbial degradation rates rarely keep pace with the spread of the pollutant. It is crucial to increase indigenous microbial degradation in the vadose zone to combat groundwater contamination...
Date: October 31, 2004
Creator: Brockman, Fred J.; Selker, John S. & Rockhold, Mark L.
Object Type: Report
System: The UNT Digital Library
Ammonia-Free NOx Control System (open access)

Ammonia-Free NOx Control System

Research is being conducted under United States Department of Energy (DOE) Contract DEFC26-03NT41865 to develop a new technology to achieve very low levels of NOx emissions from pulverized coal fired boiler systems by employing a novel system level integration between the PC combustion process and the catalytic NOx reduction with CO present in the combustion flue gas. The combustor design and operating conditions will be optimized to achieve atypical flue gas conditions. This approach will not only suppress NOx generation during combustion but also further reduce NOx over a downstream catalytic reactor that does not require addition of an external reductant, such as ammonia. This report describes the work performed during the October 1 to December 30, 2004 time period.
Date: December 31, 2004
Creator: Wu, Song; Fan, Zhen & Herman, Richard G.
Object Type: Report
System: The UNT Digital Library
Dilute Surfactant Methods for Carbonate Formations (open access)

Dilute Surfactant Methods for Carbonate Formations

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. Anionic surfactants (Alfoterra 35, 38) recover more than 40% of the oil in about 50 days by imbibition driven by wettability alteration in the core-scale. Anionic surfactant, Alfoterra-68, recovers about 28% of the oil by lower tension aided gravity-driven imbibition in the core-scale. Residual oil saturation showed little capillary number dependence between 10{sup -5} and 10{sup -2}. Wettability alteration increases as the number of ethoxy groups increases in ethoxy sulfate surfactants. Plans for the next quarter include conducting mobilization, and imbibition studies.
Date: March 31, 2004
Creator: Mohanty, Kishore K.
Object Type: Report
System: The UNT Digital Library
Tampa Electric Neural Network Sootblowing (open access)

Tampa Electric Neural Network Sootblowing

Boiler combustion dynamics change continuously due to several factors including coal quality, boiler loading, ambient conditions, changes in slag/soot deposits and the condition of plant equipment. NOx formation, Particulate Matter (PM) emissions, and boiler thermal performance are directly affected by the sootblowing practices on a unit. As part of its Power Plant Improvement Initiative program, the US DOE is providing co-funding (DE-FC26-02NT41425) and NETL is the managing agency for this project at Tampa Electric's Big Bend Station. This program serves to co-fund projects that have the potential to increase thermal efficiency and reduce emissions from coal-fired utility boilers. A review of the Big Bend units helped identify intelligent sootblowing as a suitable application to achieve the desired objectives. The existing sootblower control philosophy uses sequential schemes, whose frequency is either dictated by the control room operator or is timed based. The intent of this project is to implement a neural network based intelligent sootblowing system, in conjunction with state-of-the-art controls and instrumentation, to optimize the operation of a utility boiler and systematically control boiler fouling. Utilizing unique, on-line, adaptive technology, operation of the sootblowers can be dynamically controlled based on real-time events and conditions within the boiler. This could be …
Date: March 31, 2004
Creator: Rhode, Mark A.
Object Type: Report
System: The UNT Digital Library
Review of Catalytic Hydrogen Generation in the Defense Waste Processing Facility (DWPF) Chemical Processing Cell (open access)

Review of Catalytic Hydrogen Generation in the Defense Waste Processing Facility (DWPF) Chemical Processing Cell

This report was prepared to fulfill the Phase I deliverable for HLW/DWPF/TTR-98-0018, Rev. 2, ''Hydrogen Generation in the DWPF Chemical Processing Cell'', 6/4/2001. The primary objective for the preliminary phase of the hydrogen generation study was to complete a review of past data on hydrogen generation and to prepare a summary of the findings. The understanding was that the focus should be on catalytic hydrogen generation, not on hydrogen generation by radiolysis. The secondary objective was to develop scope for follow-up experimental and analytical work. The majority of this report provides a summary of past hydrogen generation work with radioactive and simulated Savannah River Site (SRS) waste sludges. The report also includes some work done with Hanford waste sludges and simulants. The review extends to idealized systems containing no sludge, such as solutions of sodium formate and formic acid doped with a noble metal catalyst. This includes general information from the literature, as well as the focused study done by the University of Georgia for the SRS. The various studies had a number of points of universal agreement. For example, noble metals, such as Pd, Rh, and Ru, catalyze hydrogen generation from formic acid and formate ions, and more acid …
Date: December 31, 2004
Creator: Koopman, D. C.
Object Type: Report
System: The UNT Digital Library
T-R Cycle Characterization and Imaging: Advanced Diagnostic Methodology for Petroleum Reservoir and Trap Detection and Delineation (open access)

T-R Cycle Characterization and Imaging: Advanced Diagnostic Methodology for Petroleum Reservoir and Trap Detection and Delineation

None
Date: March 31, 2004
Creator: Mancini, Ernest A.
Object Type: Report
System: The UNT Digital Library
Deep Blue No.2 Geothermal Test Well GRED II Phase II - Drilling Report (open access)

Deep Blue No.2 Geothermal Test Well GRED II Phase II - Drilling Report

Geothermal slim well driling
Date: October 31, 2004
Creator: Fairbank, Brian; Niggemann, Kim & Technology), Susan Petty (Black Mountain
Object Type: Report
System: The UNT Digital Library
Effect of Mercury-Noble Metal Interactions on SRAT Processing of SB3 Simulants (U) (open access)

Effect of Mercury-Noble Metal Interactions on SRAT Processing of SB3 Simulants (U)

Controlling hydrogen generation below the Defense Waste Processing Facility (DWPF) safety basis constrains the range of allowable acid additions in the DWPF Chemical Processing Cell. This range is evaluated in simulant tests at the Savannah River National Laboratory (SRNL). A minimum range of allowable acid additions is needed to provide operational flexibility and to handle typical uncertainties in process and analytical measurements used to set acid additions during processing. The range of allowable acid additions is a function of the composition of the feed to DWPF. Feed changes that lead to a smaller range of allowable acid additions have the potential to impact decisions related to wash endpoint control of DWPF feed composition and to the introduction of secondary waste streams into DWPF. A limited program was initiated in SRNL in 2001 to study the issue of hydrogen generation. The program was reinitiated at the end of fiscal year 2004. The primary motivation for the study is that a real potential exists to reduce the conservatism in the range of allowable acid additions in DWPF. Increasing the allowable range of acid additions can allow decisions on the sludge wash endpoint or the introduction of secondary waste streams to DWPF to …
Date: December 31, 2004
Creator: Koopman, D. C. & Baich, M. A.
Object Type: Report
System: The UNT Digital Library
Multiple Lines Of Evidence Supporting Natural Attenuation: Lines Of Inquiry Supporting Monitored Natural Attenuation And Enhanced Attenuatin Of Chlorinated Solvents (open access)

Multiple Lines Of Evidence Supporting Natural Attenuation: Lines Of Inquiry Supporting Monitored Natural Attenuation And Enhanced Attenuatin Of Chlorinated Solvents

The Department of Energy (DOE) is sponsoring an initiative to facilitate efficient, effective and responsible use of Monitored Natural Attenuation (MNA) and Enhanced Attenuation (EA) for chlorinated solvents. This Office of Environmental Management (EM) ''Alternative Project,'' focuses on providing scientific and policy support for MNA/EA. A broadly representative working group of scientists supports the project along with partnerships with regulatory organizations such as the Interstate Technology Regulatory Council (ITRC) and the United States Environmental Protection Agency (USEPA). The initial product of the technical working group was a summary report that articulated the conceptual approach and central scientific tenants of the project, and that identified a prioritized listing of technical targets for field research. This report documented the process in which: (1) scientific ground rules were developed, (2) lines of inquiry were identified and then critically evaluated, (3) promising applied research topics were highlighted in the various lines of inquiry, and (4) these were discussed and prioritized. The summary report will serve as a resource to guide management and decision making throughout the period of the subject MNA/EA Alternative Project. To support and more fully document the information presented in the summary report, the DOE is publishing a series of supplemental …
Date: December 31, 2004
Creator: Vangelas, Karen; Widemeirer, T. H.; Barden, M.J.; Dickson, W. Z. & Major, David
Object Type: Report
System: The UNT Digital Library
Stimulation Technologies for Deep Well Completions: Technical Progress Report 3 (open access)

Stimulation Technologies for Deep Well Completions: Technical Progress Report 3

The Department of Energy (DOE) is sponsoring the Deep Trek Program targeted at improving the economics of drilling and completing deep gas wells. Under the DOE program, Pinnacle Technologies is conducting a study to evaluate the stimulation of deep wells. The objective of the project is to assess U.S. deep well drilling and stimulation activity, review rock mechanics and fracture growth in deep, high-pressure/temperature wells and evaluate stimulation technology in several key deep plays. An assessment of historical deep gas well drilling activity and forecast of future trends was completed during the first six months of the project; this segment of the project was covered in Technical Progress Report No. 1. During the next six months, efforts were primarily split between summarizing rock mechanics and fracture growth in deep reservoirs and contacting operators about case studies of deep gas well stimulation as documented in Technical Progress Report No. 2. This report details work done with Anadarko and ChevronTexaco in the Table Rock Field in Wyoming.
Date: March 31, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Port of Tillamook Bay (POTB); Methane Energy Agriculture Development (MEAD); Dairy Digester Project (open access)

Port of Tillamook Bay (POTB); Methane Energy Agriculture Development (MEAD); Dairy Digester Project

The Tillamook Digester is a fully operational demonstration project that will identify the components necessary to bring the concept to a financially viable alternative for handling waste manure from dairy operations in Tillamook County.
Date: December 31, 2004
Creator: Crider, Jack
Object Type: Report
System: The UNT Digital Library
Ceramic Membrane Enabling Technology for Improved IGCC Efficiency, Quarterly Technical Progress Report: January 1 - March 31, 2004 (open access)

Ceramic Membrane Enabling Technology for Improved IGCC Efficiency, Quarterly Technical Progress Report: January 1 - March 31, 2004

This quarterly technical progress report will summarize work accomplished for Phase 2 Program during the quarter January to March 2004. In task 1 OTM development has led to improved strength and composite design for lower temperatures. In task 2, the measurement system of OTM element dimensions was improved. In task 3, a 10-cycle test of a three-tube submodule was reproduced successfully. In task 5, sizing of several potential heat recovery systems was initiated. In task 7, advanced OTM and cryogenic IGCC cases for near-term integration were developed.
Date: March 31, 2004
Creator: Prasad, Ravi
Object Type: Report
System: The UNT Digital Library
Southeast Regional Carbon Sequestration Partnership (SECARB) (open access)

Southeast Regional Carbon Sequestration Partnership (SECARB)

Work during the first six months of the project mainly concentrated on contracts execution and collection of data to characterize the region and input of that data into the geographical information system (GIS) system. Data was collected for source characterization, transportation options and terrestrial options. In addition, discussions were held to determine the extent of the geologic information that would be needed for the project. In addition, activities associated with the regulatory, permitting and safety issues were completed. Outreach activities are in the formative stages.
Date: March 31, 2004
Creator: Baskin, Kathryn A.
Object Type: Report
System: The UNT Digital Library
Hydrogen Production for Fuel Cells Via Reforming Coal-Derived Methanol (open access)

Hydrogen Production for Fuel Cells Via Reforming Coal-Derived Methanol

None
Date: December 31, 2004
Creator: Erickson, Paul A.
Object Type: Report
System: The UNT Digital Library
METHANE de-NOX for Utility PC Boilers (open access)

METHANE de-NOX for Utility PC Boilers

Preparations for conducting large-scale combustion tests with caking bituminous coal continued during the start of this quarter. Major project accomplishments related to bituminous coal testing included: a CFD preheat model and evaluation, an update of the process flow diagram and a detailed preheat burner mechanical design (suitable for construction) for firing bituminous coal. Installation and testing of the 85 MMBtu/h bituminous coal preheating system was planned to take place before the end of December. Based on the inability to conduct testing in Riley's Commercial Burner Test Facility (CBTF) during freezing weather, a schedule review indicated required site work for testing bituminous coal at the CBTF could not be completed before freezing weather set in at the site. Further bituminous preheat modification work was put on hold and efforts turned to securing the test facility over the winter season. Bituminous coal tests are therefore delayed; April-May 2005 is earliest estimate of when testing can resume. A request for a time extension was submitted to DOE to extend the project through September 2005 to allow time to secure additional funding and complete the bituminous coal testing. Removal of the PRB PC Preheater from the CBTF burner deck was completed. Decommissioning of the …
Date: December 31, 2004
Creator: Bryan, Bruce; Rabovitser, Joseph; Nester, Serguei & Wohadlo, Stan
Object Type: Report
System: The UNT Digital Library
Ceramic Coatings for Corrosion Resistant Nuclear Waste Container Evaluated in Simulated Ground Water at 90?C (open access)

Ceramic Coatings for Corrosion Resistant Nuclear Waste Container Evaluated in Simulated Ground Water at 90?C

Ceramic materials have been considered as corrosion resistant coatings for nuclear waste containers. Their suitability can be derived from the fully oxidized state for selected metal oxides. Several types of ceramic coatings applied to plain carbon steel substrates by thermal spray techniques have been exposed to 90 C simulated ground water for nearly 6 years. In some cases no apparent macroscopic damage such as coating spallation was observed in coatings. Thermal spray processes examined in this work included plasma spray, High Velocity Oxy Fuel (HVOF), and Detonation Gun. Some thermal spray coatings have demonstrated superior corrosion protection for the plain carbon steel substrate. In particular the HVOF and Detonation Gun thermal spray processes produced coatings with low connected porosity, which limited the growth rate of corrosion products. It was also demonstrated that these coatings resisted spallation of the coating even when an intentional flaw (which allowed for corrosion of the carbon steel substrate underneath the ceramic coating) was placed in the coating. A model for prediction of the corrosion protection provided by ceramic coatings is presented. The model includes the effect of the morphology and amount of the porosity within the thermal spray coating and provides a prediction of the …
Date: March 31, 2004
Creator: Haslam, J J & Farmer, J C
Object Type: Article
System: The UNT Digital Library
Combustion Turbine (CT) Hot Section Coating Life Management (open access)

Combustion Turbine (CT) Hot Section Coating Life Management

The integrity of coatings used in hot section components of combustion turbines is crucial to the reliability of the buckets. This project was initiated in recognition of the need for predicting the life of coatings analytically, and non-destructively; correspondingly, three principal tasks were established. Task 1, with the objective of analytically developing stress, strain and temperature distributions in the bucket and thereby predicting thermal fatigue (TMF) damage for various operating conditions; Task 2 with the objective of developing eddy current techniques to measure both TMF damage and general degradation of coatings and, Task 3 with the objective of developing mechanism based algorithms. Task 4 would be aimed at verifying analytical predictions from Task 1 and the NDE predictions from Task 3 against field observations. Task 5 would develop a risk-based decision analysis model to make run/repair decisions. This report is a record of the progress to date on these four tasks.
Date: March 31, 2004
Creator: Viswanathan, R.; Gandy, D.; Krzywosz, K.; Cheruvu, S. & Wan, E.
Object Type: Report
System: The UNT Digital Library
T-R Cycle Characterization and Imaging: Advanced Diagnostic Methodology for Petroleum Reservoir and Trap Detection and Delineation (open access)

T-R Cycle Characterization and Imaging: Advanced Diagnostic Methodology for Petroleum Reservoir and Trap Detection and Delineation

None
Date: December 31, 2004
Creator: Mancini, Ernest A.
Object Type: Report
System: The UNT Digital Library
Coal Integrated Gasification Fuel Cell System Study (open access)

Coal Integrated Gasification Fuel Cell System Study

This study analyzes the performance and economics of power generation systems based on Solid Oxide Fuel Cell (SOFC) technology and fueled by gasified coal. System concepts that integrate a coal gasifier with a SOFC, a gas turbine, and a steam turbine were developed and analyzed for plant sizes in excess of 200 MW. Two alternative integration configurations were selected with projected system efficiency of over 53% on a HHV basis, or about 10 percentage points higher than that of the state-of-the-art Integrated Gasification Combined Cycle (IGCC) systems. The initial cost of both selected configurations was found to be comparable with the IGCC system costs at approximately $1700/kW. An absorption-based CO2 isolation scheme was developed, and its penalty on the system performance and cost was estimated to be less approximately 2.7% and $370/kW. Technology gaps and required engineering development efforts were identified and evaluated.
Date: January 31, 2004
Creator: Balan, Chellappa; Dey, Debashis; Eker, Sukru-Alper; Peter, Max; Sokolov, Pavel & Wotzak, Greg
Object Type: Report
System: The UNT Digital Library
IEMDC - In-Line Electric Motor Driven Compressor (open access)

IEMDC - In-Line Electric Motor Driven Compressor

This report covers the fifth quarter (01/01/04 to 03/31/04) of the In-Line Electric Motor Driven Compressor (IEMDC) project. Design efforts on the IEMDC continued with compressor efforts focused on performing aerodynamic analyses. These analyses were conducted using computational fluid dynamics. Compressor efforts also entailed developing mechanical designs of components through the use of solid models and working on project deliverables. Electric motor efforts focused on the design of the magnetic bearing system, motor pressure housing, and the motor-compressor interface. The mechanical evaluation of the main interface from both the perspective of the compressor manufacturer and electric motor manufacturer indicates that an acceptable design has been achieved. All mechanical and aerodynamic design efforts have resulted in considerable progress being made towards the completion of the compressor and electric motor design and towards the successful completion of the IEMDC unit.
Date: March 31, 2004
Creator: Crowley, Michael J.
Object Type: Report
System: The UNT Digital Library
Mercury Control With The Advanced Hybrid Particulate Collector (open access)

Mercury Control With The Advanced Hybrid Particulate Collector

This project was awarded under U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) Program Solicitation DE-PS26-00NT40769 and specifically addresses Technical Topical Area 4 - Testing Novel and Less Mature Control Technologies on Actual Flue Gas at the Pilot Scale. The project team includes the Energy & Environmental Research Center (EERC) as the main contractor; W.L. Gore & Associates, Inc., as a technical and financial partner; and the Big Stone Plant operated by Otter Tail Power Company, host for the field-testing portion of the research. Since 1995, DOE has supported development of a new concept in particulate control called the advanced hybrid particulate collector (AHPC). The AHPC has been licensed to W.L. Gore and Associates, Inc., and is now marketed as the Advanced Hybrid{trademark} filter by Gore. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a unique configuration, providing major synergism between the two collection methods, both in the particulate collection step and in the transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and it solves the problem of reentrainment and re-collection of dust in conventional baghouses. The AHPC appears …
Date: March 31, 2004
Creator: Benson, Steven A.; Miller, Stanley J.; Crocker, Charlene R.; Galbreath, Kevin C.; Laumb, Jason D.; Zola, Jill M. et al.
Object Type: Report
System: The UNT Digital Library
Architectural and engineering design work for the Nevada Cancer Institute facility (open access)

Architectural and engineering design work for the Nevada Cancer Institute facility

The purpose of this project was to complete the architectural and engineering design, program planning, and other preliminary work necessary to construct the new Nevada Cancer Institute facility. These goals were accomplished with the construction of a new building of approximately 119,000 gross square feet. The facility houses the diagnostic and radio therapeutic treatment laboratories, radiation oncology treatment facility, physician offices, and clinical research areas.
Date: December 31, 2004
Creator: Murren, Heather
Object Type: Report
System: The UNT Digital Library
Enhancement of Terrestrial Carbon Sinks through the Reclamation of Abandoned Mined Lands (open access)

Enhancement of Terrestrial Carbon Sinks through the Reclamation of Abandoned Mined Lands

This project will determine the optimal forest management method to employ for each of the major commercial tree species so that profitability of timber production only or the combination of timber production and carbon sequestration is maximized. The goal of this project is to achieve DOE's long-term cost goal of sequestering carbon at $10 or less per ton. Because the potential of a forest ecosystem to sequester carbon depends on the species, site quality and management regimes utilized, this project will determine how to optimize carbon sequestration by determining how to optimally manage each species, given a range of site qualities and economic variables. This project also will determine the effects of a carbon credit market on the method and profitability of forest management, the cost of sequestering carbon, and the amount of carbon that can be sequestered. Information from this project will be used to produce user-friendly manuals which will contain economic and biological data for each of the species. These manuals will inform landowners and forest managers how to manage forests for timber and/or carbon credits, how to maximize financial returns, how much money can be earned, and how much carbon can be stored. Manuals will be disseminated …
Date: October 31, 2004
Creator: Kronrad, Gary
Object Type: Report
System: The UNT Digital Library
Novel Binders and Methods for Agglomeration of Ore (open access)

Novel Binders and Methods for Agglomeration of Ore

Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily. A primary example of this is copper heap leaching, where there are no binders that will work in the acidic environment encountered in this process. As a result, operators of acidic heap-leach facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy …
Date: March 31, 2004
Creator: Kawatra, S. K.; Eisele, T. C. & Gurtler, J. A.
Object Type: Report
System: The UNT Digital Library