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Advanced, Low/Zero Emission Boiler Design and Operation
In partnership with the U.S. Department of Energy's National Energy Technology Laboratory, B&W and Air Liquide are developing and optimizing the oxy-combustion process for retrofitting existing boilers as well as new plants. The main objectives of the project is to: (1) demonstrate the feasibility of the oxy-combustion technology with flue gas recycle in a 5-million Btu/hr coal-fired pilot boiler, (2) measure its performances in terms of emissions and boiler efficiency while selecting the right oxygen injection and flue gas recycle strategies, and (3) perform technical and economic feasibility studies for application of the technology in demonstration and commercial scale boilers. This document summarizes the work performed during the period of performance of the project (Oct 2002 to June 2007). Detailed technical results are reported in corresponding topical reports that are attached as an appendix to this report. Task 1 (Site Preparation) has been completed in 2003. The experimental pilot-scale O{sub 2}/CO{sub 2} combustion tests of Task 2 (experimental test performance) has been completed in Q2 2004. Process simulation and cost assessment of Task 3 (Techno-Economic Study) has been completed in Q1 2005. The topical report on Task 3 has been finalized and submitted to DOE in Q3 2005. The calculations …
Date:
June 30, 2007
Creator:
/Wilcox, Babcock; Geological, Illinois State; Parsons, Worley & Group, Parsons Infrastructure /Technology
System:
The UNT Digital Library
Prediction of Corrosion of Alloys in Mixed-Solvent Environments
Corrosion is much less predictable in organic or mixed-solvent environments than in aqueous process environments. As a result, US chemical companies face greater uncertainty when selecting process equipment materials to manufacture chemical products using organic or mixed solvents than when the process environments are only aqueous. Chemical companies handle this uncertainty by overdesigning the equipment (wasting money and energy), rather than by accepting increased risks of corrosion failure (personnel hazards and environmental releases). Therefore, it is important to develop simulation tools that would help the chemical process industries to understand and predict corrosion and to develop mitigation measures. To create such tools, we have developed models that predict (1) the chemical composition, speciation, phase equilibria, component activities and transport properties of the bulk (aqueous, nonaqueous or mixed) phase that is in contact with the metal; (2) the phase equilibria and component activities of the alloy phase(s) that may be subject to corrosion and (3) the interfacial phenomena that are responsible for corrosion at the metal/solution or passive film/solution interface. During the course of this project, we have completed the following: (1) Development of thermodynamic modules for calculating the activities of alloy components; (2) Development of software that generates stability diagrams …
Date:
June 5, 2003
Creator:
A. Anderko, P. Wang, R. D. Young, D. P. Riemer, P. McKenzie and M. M. Lencka (OLI Systems Inc.) & Laboratory), S. S. Babu and P. Angelini (Oak Ridge National
System:
The UNT Digital Library
Gordon Conference - Cluster, Nanocrystals and Nanostructures - July 29th - August 3rd, 2007
None
Date:
June 14, 2007
Creator:
A. Welford Castleman, Jr.
System:
The UNT Digital Library
Parallel Ion Energy Spread Due to Interaction With an Electron Bunch in the RHIC Electron Beam Cooling Solenoid
N/A
Date:
June 1, 2003
Creator:
A., Hershcovitch
System:
The UNT Digital Library
Feasibility Study of a 1.5-GeV Proton FFAG in the AGS Tunnel
N/A
Date:
June 1, 2004
Creator:
A., Ruggiero
System:
The UNT Digital Library
Local shielding requirements for the STAR detector
None
Date:
June 1, 1992
Creator:
A., Stevens
System:
The UNT Digital Library
Prediction of atmospheric δ13CO2 using fossil plant tissues. Reviews of Geophysics, 46/2006RG0002.(view/download pdf)
To summarize the content: we presented the results of laboratory experiments designed to quantify the relationship between plant tissue δ13C and δ13CO2 values under varying environmental conditions, including differential pCO2 ranging from 1 to 3 times today’s levels. As predicted, plants grown under elevated pCO2 showed increased average biomass compared to controls grown at the same temperature. Across a very large range in δ13Ca (≈ 24 ‰) and pCO2 (≈ 740 ppmv) we observed a consistent correlation between δ13Ca and δ13Cp (p<0.001). We show an average isotopic depletion of −25.4 ‰ for above-ground tissue and −23.2 ‰ for below-ground tissue of Raphanus sativus L. relative to the composition of the atmosphere under which it formed. For both above- and below-ground tissue, grown at both ~23 ˚C and ~29 ˚C, correlation was strong and significant (r2 ≥ 0.98, p<0.001); variation in pCO2 level had little or no effect on this relationship.
Date:
June 30, 2008
Creator:
A.H. Jahren, N.C. Arens and S.A. Harbeson
System:
The UNT Digital Library
Evolution of Stress in ScD{sub 2}/Cr Thin Films Fabricated by Evaporation and High Temperature Reaction
The stress of scandium dideuteride, ScD{sub 2}, thin films is investigated during each stage of vacuum processing including metal deposition via evaporation, reaction and cooldown. ScD{sub 2} films with thin Cr underlayers are fabricated on three different substrate materials: molybdenum-alumina cermet, single crystal sapphire and quartz. In all experiments, the evaporated Cr and Sc metal is relatively stress-free. However, reaction of scandium metal with deuterium at elevated temperature to form a stoichiometric dideuteride phase leads to a large compressive in-plane film stress. Compression during hydriding results from an increased atomic density compared with the as-deposited metal film. After reaction with deuterium, samples are cooled to ambient temperature, and a tensile stress develops due to mismatched coefficients of thermal expansion (CTE) of the substrate-film couple. The residual film stress and the propensity for films to crack during cooldown depends principally on the substrate material when using identical process parameters. Films deposited onto quartz substrates show evidence of stress relief during cooldown due to a large CTE misfit; this is correlated with crack nucleation and propagation within films. All ScD{sub 2} layers remain in a state of tension when cooled to 30 C. An in-situ, laser-based, wafer curvature sensor is designed and …
Date:
June 1, 2001
Creator:
ADAMS,DAVID P.; BROWN,LAURENCE E.; GOEKE,RONALD S.; ROMERO,JUAN A. & SILVA,ANDREW D.
System:
The UNT Digital Library
Power Technologies Data Book 2003 Edition
The 2003 edition of this report, prepared by NREL's Energy Analysis Office, includes up-to-date information on power technologies, including complete technology profiles. The data book also contains charts on electricity restructuring, power technology forecasts and comparisons, electricity supply, electricity capability, electricity generation, electricity demand, prices, economic indicators, environmental indicators, conversion factors, and selected congressional questions and answers.
Date:
June 1, 2004
Creator:
Aabakken, J.
System:
The UNT Digital Library
Accelerator Beam Pulsing System With Extremely Wide Range of Pulse Lengths and Pulse Repetition Rates
The following document describes the usage and results of sending pulsed beams of electrically charged particles with electrically wide range of pulse lengths and pulse repetition rates.
Date:
June 28, 1960
Creator:
Aaland, Kristian
System:
The UNT Digital Library
Temperature tests of high frequency SLIFER oscillator, LEA73-2176. [For monitoring underground nuclear detonations at Nevada Test Site]
SLIFER (Short Location Indication by Frequency of Electrical Resonance) systems measure stress wave velocity in solid or liquid materials. They monitor underground nuclear detonations at the Nevada Test Site (NTS). A shorted length of coaxial cable is a component in an oscillator's tank circuit. This sensor cable is inductive when less than one-fourth wavelength long at the oscillator's resonant frequency. The stress wave from a detonation crushes and shorts this sensor cable. As the short proceeds, inductance decreases and oscillator frequency increases. Later we convert frequency vs time to shock-front position vs time. Some doubt existed about the reliable operation of the oscillators in cold weather. Therefore these tests were conducted to check their reliability under several conditions: (1) at temperatures from -40/sup 0/ to 60/sup 0/C; (2) with three sensor cable lengths; (3) with sensor cables shorted or open at the far end; and (4) at two input power voltages. Results are presented.
Date:
June 7, 1976
Creator:
Aaron, Carl C., Jr.
System:
The UNT Digital Library
International linear collider reference design report
The International Linear Collider will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. A proposed electron-positron collider, the ILC will complement the Large Hadron Collider, a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, together unlocking some of the deepest mysteries in the universe. With LHC discoveries pointing the way, the ILC -- a true precision machine -- will provide the missing pieces of the puzzle. Consisting of two linear accelerators that face each other, the ILC will hurl some 10 billion electrons and their anti-particles, positrons, toward each other at nearly the speed of light. Superconducting accelerator cavities operating at temperatures near absolute zero give the particles more and more energy until they smash in a blazing crossfire at the centre of the machine. Stretching approximately 35 kilometres in length, the beams collide 14,000 times every second at extremely high energies -- 500 billion-electron-volts (GeV). Each spectacular collision creates an array of new particles that could answer some of the most fundamental questions of all time. The current baseline design allows for an upgrade to a 50-kilometre, 1 trillion-electron-volt (TeV) machine during the second stage of …
Date:
June 22, 2007
Creator:
Aarons, G.
System:
The UNT Digital Library
BIGFLOW: A numerical code for simulating flow in variably saturated, heterogeneous geologic media. Theory and user`s manaual, Version 1.1
This report documents BIGFLOW 1.1, a numerical code for simulating flow in variably saturated heterogeneous geologic media. It contains the underlying mathematical and numerical models, test problems, benchmarks, and applications of the BIGFLOW code. The BIGFLOW software package is composed of a simulation and an interactive data processing code (DATAFLOW). The simulation code solves linear and nonlinear porous media flow equations based on Darcy`s law, appropriately generalized to account for 3D, deterministic, or random heterogeneity. A modified Picard Scheme is used for linearizing unsaturated flow equations, and preconditioned iterative methods are used for solving the resulting matrix systems. The data processor (DATAFLOW) allows interactive data entry, manipulation, and analysis of 3D datasets. The report contains analyses of computational performance carried out using Cray-2 and Cray-Y/MP8 supercomputers. Benchmark tests include comparisons with other independently developed codes, such as PORFLOW and CMVSFS, and with analytical or semi-analytical solutions.
Date:
June 1, 1993
Creator:
Ababou, R. & Bagtzoglou, A. C.
System:
The UNT Digital Library
Combined approach to the inverse protein folding problem. Final report
The main scientific contribution of the project ''Combined approach to the inverse protein folding problem'' submitted in 1996 and funded by the Department of Energy in 1997 is the formulation and development of the idea of the multilink recognition method for identification of functional and structural homologues of newly discovered genes. This idea became very popular after they first announced it and used it in prediction of the threading targets for the CASP2 competition (Critical Assessment of Structure Prediction).
Date:
June 1, 2000
Creator:
Abagyan, Ruben A.
System:
The UNT Digital Library
Federal Environmental activities
This report presents the Environmental activities of all units of the federal government except the supreme court and the committees of congress.
Date:
June 1, 1972
Creator:
Abbasi, Susan R.
System:
The UNT Digital Library
Development of novel copper-based sorbents for hot-gas cleanup. [Quarterly] technical report, December 1, 1993--February 28, 1994
The objective of this investigation is to evaluate two novel copper-based sorbents, namely copper-chromium and copper-cerium, for their effectiveness in removing hydrogen sulfide from fuel gas in the temperature range of 650{degree} to 850{degree}. Such high temperatures will be required for the new generation of gas turbines (inlet >750{degree}C) in Integrated Gasification Combined Cycle (IGCC) systems. The effect of pre-reduction with H{sub 2}, in the presence of H{sub 2}O on the performance of the sorbents in cyclic sulfidation/regeneration, was studied in a thermogravimetric analyzer (TGA) and in a fixed-bed reactor at 750{degree}C. The results of the TGA tests indicate that pre-reduction of the sorbents is very fast in either 10% or 30% H{sub 2}. Without sorbent pre-reduction, sulfidation consists of two-stages, a reduction-dominating and a sulfidation-dominating stage. Sulfidation apparently takes place before reduction is complete. During regeneration some copper/cerium sulfates may have formed and Cu{sub 2}O may have formed in addition to CuO. The fixed-bed reactor tests show that at 750{degree}C: (1) prereducing the CuO-Cr{sub 2}O{sub 3} with H{sub 2} does not effect the reactivity of the sorbent towards H{sub 2}S at either the high or low H{sub 2} feed gas concentrations and (2) when 30% H{sub 2} was used …
Date:
June 1, 1994
Creator:
Abbasian, J.; Hill, A. H.; Flytzani-Stephanopoulos, M. & Li, Zhijiang
System:
The UNT Digital Library
Sulfur removal in advanced two-stage fluidized-bed combustion. [Quarterly] technical report, December 1, 1993--February 28, 1994
The objective of this study is to obtain data on the rates of reaction between, hydrogen sulfide (H{sub 2}S) and uncalcined calcium-based sorbents under operating conditions relevant to first stage (carbonizer) of Advanced Two-Stage Pressurized Fluidized-Bed Combustors (PFBC). In these systems the CO{sub 2} partial pressure in the first stage generally exceeds the equilibrium value for calcium carbonate decomposition. Therefore, removal of sulfur compounds takes place through the reaction between H{sub 2}S and calcium carbonate. To achieve this objective the rates of reaction between hydrogen sulfide and uncalcined calcium-based sorbents will be determined by conducting tests in pressurized thermogravimetric analyzer (TGA) and high-pressure/high-temperature fluidized-bed reactor (HPTR) units. The effects of sorbent type, sorbent particle size, reactor temperature and pressure, and CO{sub 2} and H{sub 2}S partial pressures on the sulfidation reaction rate will be determined. During this quarter, the high-pressure thermogravimetric analyzer (HPTGA) unit was installed and the shakedown process was completed. Several tests were conducted in the HPTGA unit to establish the operating procedure and the repeatability of the experimental results. Sulfidation by conducting the baseline sulfidation tests. The results are currently being analyzed.
Date:
June 1, 1994
Creator:
Abbasian, J.; Hill, A. H.; Wangerow, J. R. & Rue, D. M.
System:
The UNT Digital Library
Development of Highly Durable and Reactive Regenerable Magnesium-Based Sorbents for CO2 Separation in Coal Gasification Process
The specific objective of this project was to develop physically durable and chemically regenerable MgO-based sorbents that can remove carbon dioxide from raw coal gas at operating condition prevailing in IGCC processes. A total of sixty two (62) different sorbents were prepared in this project. The sorbents were prepared either by various sol-gel techniques (22 formulations) or modification of dolomite (40 formulations). The sorbents were prepared in the form of pellets and in granular forms. The solgel based sorbents had very high physical strength, relatively high surface area, and very low average pore diameter. The magnesium content of the sorbents was estimated to be 4-6 % w/w. To improve the reactivity of the sorbents toward CO{sub 2}, The sorbents were impregnated with potassium salts. The potassium content of the sorbents was about 5%. The dolomite-based sorbents were prepared by calcination of dolomite at various temperature and calcination environment (CO{sub 2} partial pressure and moisture). Potassium carbonate was added to the half-calcined dolomite through wet impregnation method. The estimated potassium content of the impregnated sorbents was in the range of 1-6% w/w. In general, the modified dolomite sorbents have significantly higher magnesium content, larger pore diameter and lower surface area, resulting …
Date:
June 1, 2005
Creator:
Abbasian, Javad; Khayyat, Armin Hassanzadeh & Slimane, Rachid B.
System:
The UNT Digital Library
Design considerations for the development of a space qualification Short Wavelength Imaging Fourier Transform Spectrometer (SWIFTS)
This document is the final report on work performed at Sandia National Laboratories during FY 1992 and 1993 for a Laboratory Directed Research and Development (LDRD) program to look at problems associated with the design and long term operation of a short wavelength imaging Fourier Transform (FT) spectrometer for use in space. In attempts to answer two fundamental questions: is a FT spectrometer with a resolution of 1 cm{sup {minus}1} covering the silicon detector wavelength range of 0.4 to 1.1 microns feasible in a long life space instrument and, if so, is it the best method of obtaining the desired information? Emphasis has been on identifying methods which minimize reliance on precision mechanical alignment and precise velocity control. An important consideration has also been to develop methods which will be compatible with a variety of self-scanning solid state imaging devices. A breadboard instrument was constructed using cube corner retroreflectors and a laser diode position reference. Some preliminary results are reported. This work is primarily intended to act as an aid to engineers at Sandia who wish to pursue the fabrication of a flight qualified instrument. The theoretical parts are intended to be somewhat tutorial in nature to aid the engineer …
Date:
June 1, 1997
Creator:
Abbink, R. E.
System:
The UNT Digital Library
Tests of four models representing intermediate sections of the XB-33 airplane including sections with slotted flap and ailerons
Report presenting testing in the two-dimensional tunnel of four models submitted by the Glenn L. Martin Company as intermediate sections of the wing of the XB-33 airplane. Each airfoil model had different types of flaps or no flaps at all. Results regarding the lift and drag data, lift coefficients, effect of flap positions, aileron effects, drag coefficients, and hinge-moment coefficients are provided.
Date:
June 1942
Creator:
Abbott, Ira H.
System:
The UNT Digital Library
AGR-2 Data Qualification Report for ATR Cycles 149B, 150A, 150B, 151A, and 151B
This report provides the data qualification status of AGR-2 fuel irradiation experimental data from Advanced Test Reactor (ATR) cycles 149B, 150A, 150B, 151A, and 151B), as recorded in the Nuclear Data Management and Analysis System (NDMAS). The AGR-2 data streams addressed include thermocouple temperatures, sweep gas data (flow rate, pressure, and moisture content), and fission product monitoring system (FPMS) data for each of the six capsules in the experiment. A total of 3,307,500 5-minute thermocouple and sweep gas data records were received and processed by NDMAS for this period. There are no AGR-2 data for cycle 150A because the experiment was removed from the reactor. Of these data, 82.2% were determined to be Qualified based on NDMAS accuracy testing and data validity assessment. There were 450,557 Failed temperature records due to thermocouple failures, and 138,528 Failed gas flow records due to gas flow cross-talk and leakage problems that occurred in the capsules after cycle 150A. For FPMS data, NDMAS received and processed preliminary release rate and release-to-birth rate ratio (R/B) data for the first three reactor cycles (cycles 149B, 150B, and 151B). This data consists of 45,983 release rate records and 45,235 R/B records for the 12 radionuclides reported. The …
Date:
June 1, 2012
Creator:
Abbott, Michael L. & Pham, Binh T.
System:
The UNT Digital Library
Critical-fluid extraction of organics from water. Volume II. Experimental. Final report, 1 October 1979-30 November 1983
Critical fluid extraction has been tested at the pilot plant scale as a method of separating organics from water. The process employed resembles a liquid-liquid extraction in which the solvent is near-critical carbon dioxide and the feed is an organic in aqueous solution. Carbon dioxide's solvent and other thermodynamic properties, and the effective utilization of a vapor recompression cycle in the process design have significantly reduced the energy required for these separations. This process is an energy-conserving alternative to the distillation processes which are currently employed. The objectives of this portion of the project were to demonstrate the feasibility of this technology and to gather the engineering data required to evaluate the process. Three alcohols were tested in these experiments - ethanol, isopropanol and sec-butanol - and were all successfully extracted.
Date:
June 1, 1984
Creator:
Abboud, O. K.; de Filippi, R. P.; Goklen, K. E. & Moses, J. M.
System:
The UNT Digital Library
Colloid-Facilitated Plutonium Transport in Saturated Alluvium
Natural groundwater colloids have been recognized as possible agents for enhancing the subsurface transport of strongly-sorbing radionuclides. To evaluate this mechanism, packed-bed column experiments were conducted comparing the simultaneous transport of dissolved plutonium (Pu), Pu sorbed onto natural colloids, 190-nm and 500-nm diameter fluorescent CML microspheres, and tritiated water in saturated alluvium. Experiments were conducted in two columns having slightly different porosities at two flow rates, resulting in average linear velocities (v{sub z}) of 0.6 to 3.65 cm/hr in one column and 0.57 to 2.85 cm/hr in the other. In all experiments, Pu associated with natural colloids transported through alluvium essentially unretarded, while dissolved Pu was entirely retained. These results were consistent with the strong sorption of Pu to alluvium and the negligible desorption from natural colloids, observed in separate batch experiments, over time scales exceeding those of the column experiments. Breakthroughs of natural colloids preceded tritiated water in all experiments, indicating a slightly smaller effective pore volume for the colloids. The enhancement of colloids transport over tritiated water decreased with v{sub z}, implying {approx} 40% enhancement at v{sub z} = 0. The 500-nm CML microspheres were significantly attenuated in the column experiments compared to the 190-nm microspheres, which exhibited …
Date:
June 1, 2004
Creator:
Abdel-Fattah, A.; Reimus, P.; Ware, S. & Haga, M.
System:
The UNT Digital Library
Hazardous materials in Aquatic environments of the Mississippi River basin. Quarterly project status report, 1 January 1994--30 March 1994
Projects associated with this grant for studying hazardous materials in aquatic environments of the Mississippi River Basin are reviewed and goals, progress and research results are discussed. New, one-year initiation projects are described briefly.
Date:
June 1, 1994
Creator:
Abdelghani, A.
System:
The UNT Digital Library