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Evaluation of trommels for waste-to-energy plants: Phase 1 report of the Doncaster and Byker test series

Description: The performance testing of two commercial scale trommels, used for size separation of bulk municipal waste and the first phase of the testwork carried out are reported. The commercial scale trommels examined during this testwork are sited at Doncaster and at Byker. The major difference between the two plants is that raw refuse is processed in the Doncaster plant trommel and pulverised refuse in the Byker plant trommel. Both plants produce a magnetic ferrous fraction as well as a refuse derived fuel prepared by upgrading the intermediate sized product from the rotary screen using air classification, magnetic separation, further size reduction and pelletization. However, they differ in many respects; the feed to the Byker trommel is preshredded (-7'') while that at Doncaster is treated as received and the latter plant also has additional facilities for glass and paper recovery. The report provides detailed accounts of the Byker and Doncaster tests and compares the two screening operations highlighting the effects of the major variables investigated. These results highlight the current lack of understanding of trommel processes in that both series unequivocally demonstrate considerable errors in the design ratings assigned to each unit. Accordingly, the results of the Byker tests relate largely to overloaded conditions, particularly in the fine screen section, while those from the Doncaster tests represent conditions of considerable underloading.Valuable information relating to the effects of trommel speed, installation of lifters and scrolls, aperture size selection and mode of particle presentation to the screen plante has been reported in addition to the experience and methods of interpreting data resulting from the use of surrogate pulses. (MCW)
Date: December 1, 1981
Creator: Barton, J.
Partner: UNT Libraries Government Documents Department

In-house supervisory program for operations supervisors

Description: Additional lead operators were needed by the LASL computer operations group. The selection process and criteria are briefly described, and an example of the selection matrix is given. The new lead operators (and others) were in need of a brief course in basic supervision; the outline of the course provided is presented. 2 figures. (RWR)
Date: January 1, 1979
Creator: Barton, J.
Partner: UNT Libraries Government Documents Department

Angle-resolved photoemission extended fine structure

Description: Measurements of the Angle-Resolved Photoemission Extended Fine Structure (ARPEFS) from the S(1s) core level of a c(2 x 2)S/Ni(001) are analyzed to determine the spacing between the S overlayer and the first and second Ni layers. ARPEFS is a type of photoelectron diffraction measurement in which the photoelectron kinetic energy is swept typically from 100 to 600 eV. By using this wide range of intermediate energies we add high precision and theoretical simplification to the advantages of the photoelectron diffraction technique for determining surface structures. We report developments in the theory of photoelectron scattering in the intermediate energy range, measurement of the experimental photoemission spectra, their reduction to ARPEFS, and the surface structure determination from the ARPEFS by combined Fourier and multiple-scattering analyses. 202 refs., 67 figs., 2 tabs.
Date: March 1, 1985
Creator: Barton, J.J.
Partner: UNT Libraries Government Documents Department

Uninterruptable power source for a large computer facility

Description: An uninterruptable power source was needed to protect critical elements of a computer complex from short power outages and glitches, many of them lightning related. A consultant was hired to help in this task and proved invaluable. The equipment purchased provides glitch-free power under many fault conditions. Installation proved to be a major problem as far as money and time were concerned. The system is now ready to be switched over to drive the critical load. The project appears to be a success and should pay for itself many times over.
Date: January 1, 1979
Creator: Barton, J. & Tolmie, D.E.
Partner: UNT Libraries Government Documents Department

ARG portable neutron radiography. Final report

Description: In this report all available neutron radiographic data, including results of tests run at LANL, McClellan AFB, and University of Virginia, will be combined to outline specific transportable neutron radiography systems that could achieve the desired results as a complement to x-radiography capabilities for the Accident Response Group (ARG).
Date: April 1, 1995
Creator: Barton, J.P.
Partner: UNT Libraries Government Documents Department

FOURIER ANALYSIS OF EXTENDED FINE STRUCTURE WITH AUTOREGRESSIVE PREDICTION

Description: Autoregressive prediction is adapted to double the resolution of Angle-Resolved Photoemission Extended Fine Structure (ARPEFS) Fourier transforms. Even with the optimal taper (weighting function), the commonly used taper-and-transform Fourier method has limited resolution: it assumes the signal is zero beyond the limits of the measurement. By seeking the Fourier spectrum of an infinite extent oscillation consistent with the measurements but otherwise having maximum entropy, the errors caused by finite data range can be reduced. Our procedure developed to implement this concept applies autoregressive prediction to extrapolate the signal to an extent controlled by a taper width. Difficulties encountered when processing actual ARPEFS data are discussed. A key feature of this approach is the ability to convert improved measurements (signal-to-noise or point density) into improved Fourier resolution.
Date: January 1, 1985
Creator: Barton, J. & Shirley, D.A.
Partner: UNT Libraries Government Documents Department

HIGH RESOLUTION FOURIER ANALYSIS WITH AUTO-REGRESSIVE LINEAR PREDICTION

Description: Auto-regressive linear prediction is adapted to double the resolution of Angle-Resolved Photoemission Extended Fine Structure (ARPEFS) Fourier transforms. Even with the optimal taper (weighting function), the commonly used taper-and-transform Fourier method has limited resolution: it assumes the signal is zero beyond the limits of the measurement. By seeking the Fourier spectrum of an infinite extent oscillation consistent with the measurements but otherwise having maximum entropy, the errors caused by finite data range can be reduced. Our procedure developed to implement this concept adapts auto-regressive linear prediction to extrapolate the signal in an effective and controllable manner. Difficulties encountered when processing actual ARPEFS data are discussed. A key feature of this approach is the ability to convert improved measurements (signal-to-noise or point density) into improved Fourier resolution.
Date: April 1, 1984
Creator: Barton, J. & Shirley, D.A.
Partner: UNT Libraries Government Documents Department

High frame-rate neutron radiography of dynamic events

Description: A system has been developed to perform neutron radiographic analysis of dynamic events having a duration of several milliseconds. The system has been operated in the range of 2000 to 10,000 frames/second. Synchronization has provided high-speed-motion neutron radiographs for evaluation of the firing cycle of 7.62 mm munition rounds within a steel rifle barrel. The system has also been used to demonstrate the ability to produce neutron radiographic movies of two-phase flow. The equipment uses the Oregon State University TRIGA reactor capable of pulsing to 3000 MW peak power, a neutron beam collimator, a scintillator neutron conversion screen coupled to an image intensifier, and a 16 mm high speed movie camera. The peak neutron flux incident at the object position is approximately 4 x 10/sup 11/ n/cm/sup 2/s with a pulse, full width at half maximum, of 9 ms. Special studies have been performed on the scintillator conversion screens and on the effects of statistical limitations on the image quality. Modulation transfer function analysis has been used to assist in the evaluation of the system performance.
Date: November 20, 1981
Creator: Bossi, R.H.; Robinson, A.H. & Barton, J.P.
Partner: UNT Libraries Government Documents Department

Stabilization of Mercury in High pH Tank Sludges

Description: DOE complex contains many tank sludges contaminated with mercury. The high pH of these tank sludges typically fails to stabilize the mercury, resulting in these radioactive wastes also being characteristically hazardous or mixed waste. The traditional treatment for soluble inorganic mercury species is precipitation as insoluble mercuric sulfide. Sulfide treatment and a commercial mercury-stabilizing product were tested on surrogate sludges at various alkaline pH values. Neither the sulfide nor the commercial product stabilized the mercury sufficiently at the high pH of the tank sludges to pass the Toxicity Characteristic Leach Procedure (TCLP) treatment standards of the Resource Conservation and Recovery Act (RCRA). The commercial product also failed to stabilize the mercury in samples of the actual tank sludges.
Date: February 24, 2003
Creator: Spence, R. & Barton, J.
Partner: UNT Libraries Government Documents Department

Multi-purpose neutron radiography system

Description: A conceptual design is given for a low cost, multipurpose radiography system suited for the needs of the Los Alamos National Laboratory (LANL). The proposed neutron source is californium-252. One purpose is to provide an in-house capability for occasional, reactor quality, neutron radiography thus replacing the recently closed Omega-West Reactor. A second purpose is to provide a highly reliable standby transportable neutron radiography system. A third purpose is to provide for transportable neutron probe gamma spectroscopy techniques. The cost is minimized by shared use of an existing x-ray facility, and by use of an existing transport cask. The achievable neutron radiography and radioscopy performance characteristics have been verified. The demonstrated image qualities range from high resolution gadolinium - SR film, with L:D = 100:1, to radioscopy using a LIXI image with L:D = 30:1 and neutron fluence 3.4 x 10{sup 5} n/cm{sup 2}.
Date: July 1, 1996
Creator: Barton, J.P.; Bryant, L.E. & Berry, P.
Partner: UNT Libraries Government Documents Department

A comparison of chilled DI water/ozone and CO{sub 2}-based supercritical fluids as replacements for photoresist-stripping solvents

Description: Part of the Hewlett Packard Components Group`s Product Stewardship program is the ongoing effort to investigate ways to eliminate or reduce as much as possible the use of chemical substances from manufacturing processes. Currently used techniques to remove hard-baked photoresists from semiconductor wafers require the use of inorganic chemicals or organic strippers and associated organic solvents. Environmental, health and safety, as well as cost considerations prompted the search for alternative, more environmentally-benign, and cost-effective solutions. Two promising, emerging technologies were selected for evaluation: the chilled DI water/ozone technique and supercritical fluids based on carbon dioxide (CO{sub 2}). Evaluating chilled DI water/ozone shows this process to be effective for positive photoresist removal, but may not be compatible with all metallization systems. Testing of a closed-loop CO{sub 2}-based supercritical CO{sub 2} Resist Remover, or SCORR, at Los Alamos, on behalf of Hewlett-packard, shows that this treatment process is effective in removing photoresists, and is fully compatible with commonly used metallization systems. In this paper, the authors present details on the testing programs conducted with both the chilled DI H{sub 2}O/ozone and SCORR treatment processes.
Date: October 1998
Creator: Rubin, J. B.; Davenhall, L. B.; Barton, J.; Taylor, C. M. V. & Tiefert, K.
Partner: UNT Libraries Government Documents Department

Estimation of mass transfer and kinetics in operating biofilters for removal of VOCs

Description: Long-term, stable operation of trickle-bed bioreactors remains desirable, but is difficult to achieve for industrial processes, which generate continuous streams of dilute gaseous hydrocarbons. Mass transfer and kinetic parameters are difficult to measure, complicating predictive estimates. Two methods are presented which were used to predict the importance of mass transfer versus kinetics limitations in operating trickle-bed biofilters. Both methods altered the overall kinetic activity of the biofilter and estimated the effective mass transfer coefficient (K{sub 1}a) by varying the VOC (volatile organic contaminant) loading rate and concentration. The first method, used with developing biofilters possessing low biomass, involved addition of cultured biomass to the recirculating liquid to effect an overall change in VOC removal capacity. The second method altered the total bed temperature of a well-established biofilter to effect a change. Results and modeling from these experiments are presented for a mixed culture biofilter which is capable of consuming sparingly soluble alkanes, such as pentane and isobutane. Methods to control overgrowth are discussed which were used to operate one reactor continuously for over 24 months with sustained degradation of VOC alkanes with a rate of 50 g/h/m{sup 3}.
Date: November 18, 1997
Creator: Barton, J.W.; Davison, B.H. & Gable, C.C.
Partner: UNT Libraries Government Documents Department

Photoelectron holography of platinum (111)

Description: Platinum atoms near a (111) single-crystal face have been imaged using photoelectron holography. Electron angular intensity patterns were collected at equally spaced wavenumbers from 6 to 12{Angstrom}{sup {minus}1}. Images of atoms near expected atomic positions are obtained from single-wavenumber analyses over the range of the data set. Positions are detected further from the emitter than we have seen previously, and symmetry assumptions are not required. We have also adopted a three dimensional means of representing the data in order to help understand the results. Twin image suppression and artifact reduction in the holographically reconstructed data are set are obtained when images at different wavenumbers are correctly phase-summed. We are assessing the capability of the technique for rendering true three-dimensional structural information for unknown systems.
Date: April 1, 1993
Creator: Petersen, B.L.; Terminello, L.J.; Barton, J.J. & Shirley, D.A.
Partner: UNT Libraries Government Documents Department

The Los Alamos FEL photoinjector drive laser

Description: The drive laser system of the photoelectric injector for the Los Alamos free -- electron laser (FEL) is described. the bright electron beams required for high performance FELs demand stringnt specifications on drive laser output levels, beam quality, and stability. The laser system generates 7--15 ps (FWHM) Gaussian pulses of 527 nm light at a repetition rate of 21.67 MHz. These micropulses'' are contained within a < 200 microsec long macropulse'' envelope which is emitted from the drive laser at a 1 Hz rate. Micropulse energies as large as 12 microjoules are obtained. The design specifications, laser architecture, and operating performance following the most recent round of upgrades are presented. 10 refs., 15 figs., 1 tab.
Date: January 1, 1991
Creator: Early, J.; Barton, J.; Busch, G.; Wenzel, R. & Remelius, D.
Partner: UNT Libraries Government Documents Department

Mobility and trapping time measurements in HgI/sub 2/

Description: The charge transport parameters of a solid-state radiation detector are of paramount importance in determining its spectrometric performance. In this paper various methods of determining mobilities and trapping times for electrons and holes in mercuric iodide (HgI/sub 2/) are reviewed, including mobility-trapping time products via the Hecht relation, mobility measurements by voltage pulse risetime determination, and mobility and trapping time by current pulse shape analysis. Experimental results for HgI/sub 2/ detectors are presented for the different types of measurements described. Among the experimental results presented are three noteworthy items: (1) trapping times for electrons and holes in a variety of different crystals and detectors were obtained from a combination of ..mu..tau and ..mu.. measurements, (2) a new two-source type of experimental setup was developed which gives both the electron and hole pulse spectra simultaneously, and (3) for a one-centimeter thick HgI/sub 2/ detector studied by means of current pulse shape analysis a value of at least 0.03 cm/sup 2//V was found for the product of electron mobility and trapping time; this is the highest value ever reported for HgI/sub 2/ and indicates the quality of electron charge transport parameters that can be attained for this material. 12 references.
Date: January 1, 1983
Creator: Kusmiss, J.H.; Iwanczyk, J.S.; Barton, J.B.; Dabrowski, A.J. & Seibt, W.
Partner: UNT Libraries Government Documents Department

Biofiltration of volatile pollutants: Engineering mechanisms for improved design, long-term operation, prediction and implementation. 1998 annual progress report

Description: 'Biofiltration systems can be used for treatment of volatile organic compounds (VOCs); however, the systems are poorly understood and are currently operated as black boxes. Common operational problems associated with biofilters include fouling, deactivation, and overgrowth, all of which make them ineffective for continuous, long-term use. The objective of this investigation is to develop generic methods for long-term stable operation, in particular by using selective limitation of supplemental nutrients while maintaining high activity. As part of this effort, the author will provide deeper fundamental understanding of the important biological and transport mechanisms in biodestruction of sparingly soluble VOCs and extend this approach and mathematical models to additional systems of high priority EM relevance--direct degradation and cometabolic degradation of priority pollutants such as BTEX and chlorinated organics. This report summarizes work after 2 years of a 3-year project. Major results are enumerated and discussed'
Date: June 1, 1998
Creator: Davison, B.H.; Klasson, K.T. & Barton, J.W.
Partner: UNT Libraries Government Documents Department

Biofiltration of volatile pollutants: Engineering mechanisms for improved design, long-term operation, prediction, and implementation. 1997 annual progress report

Description: 'Biofiltration systems can be used to treat volatile organic compounds (VOCs); however, the systems are poorly understood and are currently operated as black boxes. Common operational problems associated with biofilters include fouling, deactivation, and overgrowth, all of which make biofilters ineffective for continuous, long-term use. The objective of this investigation is to develop generic methods for long-term stable operation, in particular by using selective limitation of supplemental nutrients while maintaining high activity and the ability to regenerate biofilter activity. As part of this effort, the authors will provide a deeper fundamental understanding of the important biological and transport mechanisms in biodestruction of sparingly soluble VOCs and will extend this engineering approach and developed mathematical models to two additional systems of high-priority environmental management (EM) relevance-direct degradation and cometabolic degradation of priority pollutants such as BTEX (benzene, toluene, ethylbenzene, and xylene) and TCE (trichioroethylene), respectively. Preliminary results indicate that the author can control overgrowth of the biofilm while sustaining high degradation rates and develop basic predictive models that elucidate mass transfer and kinetic limitations in this system for alkanes. The alkanes are degraded into CO, and waterwith minimal biomass (due to the methodology proposed). This system will be used to test and model additional supplemental nutrient feeding strategies as well as methods to increase the fundamental driving forces by modification of the system. Models will be extended to non-steady-state, long-term operation. The author will examine the nature of the mixed microbial community in the VOC-degrading biofilm and test for new degradative activities. He will use cosolvents with surfactant properties to enhance hydrocarbon solubility in the biofilm and evaluate their impact on mass transfer and reaction rate in an operating biofilter. These results will point to further potential improvements in systems of EM priority. Constructed and acclimated three trickling-bed biofilters. Measured kinetic ...
Date: September 1, 1997
Creator: Davison, B.H.; Klasson, K.T. & Barton, J.W.
Partner: UNT Libraries Government Documents Department

Angle-resolved photoemission extended fine structure

Description: Core level angle-resolved photoemission intensity oscillates sinusoidally with increasing photoelectron momentum. Interference between direct and scattered photo-emission causes this angle-resolved photoemission extended fine structure (ARPEFS). We will discuss an analytic single-scattering theory which quantitatively describes the oscillations. The procedures for extracting surface geometry information from photoemission measurements will be illustrated with S(1s) ARPEFS from S on Ni(100) and Cu(100) obtained with the soft X-ray double crystal monochromator at the Stanford Synchrotron Radiation Laboratory. Building on the surface sensitivity and chemical selectivity of photoemission, ARPEFS analysis provides direct geometrical information from the oscillation frequencies (derived with auto-regressive Fourier analysis), from intensity changes with polarization and analyzer position, and from analysis of scattering phase-shift zero-crossings.
Date: September 1, 1983
Creator: Barton, J.J.; Bahr, C.C.; Hussain, Z.; Robey, S.W.; Klebanoff, L.E. & Shirley, D.A.
Partner: UNT Libraries Government Documents Department

Place of HgI/sub 2/ energy-dispersive x-ray detectors

Description: After a review of solid-state conduction counters, in general, and of the history of mercuric iodide, in particular, the theory of operation of solid-state energy-dispersive HgI/sub 2/ detectors is dicusssed. The main factors which limit energy resolution in solid-state compound detectors are considered, including statistical fluctuations in charge generation, the window effect, trapping, inhomogeneities in the detector material, and electronic noise. Potential applications of room-temperature HgI/sub 2/ x-ray detectors are listed, and general considerations are discussed for x-ray fluorescence analysis with HgI/sub 2/. Directions of current investigations are given. (LEW)
Date: January 1, 1982
Creator: Dabrowski, A.J.; Huth, G.C.; Iwanczyk, J.S.; Kusmiss, J.H.; Barton, J.S.; Szymczyk, J.M. et al.
Partner: UNT Libraries Government Documents Department

Predictive mathematical modeling of trickling bed biofilters for elucidating mass transfer and kinetic effects

Description: Mathematical models of varying complexity have been proposed in the open literature for describing uptake of volatile organics in trickling bed biofilters. Many simpler descriptions yield relatively accurate solutions, but are limited as predictive tools by numerous assumptions which decrease the utility of the model. Trickle bed operation on the boundary between mass transfer and kinetic limitation regimes serves as one example in which these models may be insufficient. One-dimensional models may also fail to consider important effects/relationships in multiple directions, limiting their usefulness. This paper discusses the use of a predictive, two-dimensional mathematical model to describe microbial uptake, diffusion through a biofilm, and mass transfer of VOCs from gas to liquid. The model is validated by experimental data collected from operating trickle-bed bioreactors designed for removing sparingly soluble gaseous contaminants. Axial and radial (biofilm) concentration profiles are presented, along with validation results. Operation in regimes in which both mass transfer and kinetic factors play significant roles are discussed, along with predictive modeling implications.
Date: March 1, 1998
Creator: Barton, J.W.; Zhang, X.S.; Klasson, K.T. & Davison, B.H.
Partner: UNT Libraries Government Documents Department

Removal of chlorinated and non-chlorinated alkanes in a trickle-bed biofilter

Description: Increasing restrictions in emissions from a variety of industrial settings demand low cost removal of dilute contaminants in air. Many of these contaminants such as volatile organic components (VOCs) and sulfur compounds are biodegradable and can be removed from air streams via biofiltration. The simplest form of biofiltration consists of compost-based systems. More advanced systems designed for unique contaminants are biofilters with bioactive structured packing operating in trickle-bed mode. These advanced systems rely on a microbial consortium capable of degrading the contaminants of concern and the consortium usually is isolated or enriched from a more complex microbial mixture. This paper describes the use of a trickle-bed reactor seeded with a microbial consortium enriched from a methanotrophic culture. The microbial consortium has been found to degrade chlorinated alkanes as the sole carbon source. Degradation rates of alkane mixtures are presented for the trickle-bed as well as results from batch cultures experiments designed to study degradation of various chlorinated and non-chlorinated VOCs.
Date: January 1, 1998
Creator: Klasson, K.T.; Davison, B.H.; Barton, J.W. & Jacobs, J.E.
Partner: UNT Libraries Government Documents Department

Performance of room temperature mercuric iodide (HgI/sub 2/) detectors in the ultra low energy x-ray region

Description: Performance of room temperature mercuric iodide x-ray spectrometers has been recently improved through new fabrication techniques and further development of low noise associated electronic systems. This progress has extended the range of measurements to the ultra low energy x-ray region at room temperature. This paper reports the study of the effect of contact material on the performance of HgI/sub 2/ detectors in the low energy x-ray region.
Date: January 1, 1980
Creator: Dabrowski, A.J.; Iwanczyk, J.S.; Barton, J.B.; Huth, G.C.; Whited, R.; Ortale, C. et al.
Partner: UNT Libraries Government Documents Department