Science.gov

Sample records for stack gas particulate

  1. Cooler and particulate separator for an off-gas stack

    DOEpatents

    Wright, G.T.

    1991-04-08

    This report describes an off-gas stack for a melter, furnace or reaction vessel comprising an air conduit leading to two sets of holes, one set injecting air into the off-gas stack near the melter plenum and the second set injecting air downstream of the first set. The first set injects air at a compound angle, having both downward and tangential components, to create a reverse vortex flow, counter to the direction of flow of gas through the stack and also along the periphery of the stack interior surface. Air from the first set of holes prevents recirculation zones from forming and the attendant accumulation of particulate deposits on the wall of the stack and will also return to the plenum any particulate swept up in the gas entering the stack. The second set of holes injects air in the same direction as the gas in the stack to compensate for the pressure drop and to prevent the concentration of condensate in the stack. A set of sprayers, receiving water from a second conduit, is located downstream of the second set of holes and sprays water into the gas to further cool it.

  2. Cooler and particulate separator for an off-gas stack

    DOEpatents

    Wright, George T.

    1992-01-01

    An off-gas stack for a melter comprising an air conduit leading to two sets of holes, one set injecting air into the off-gas stack near the melter plenum and the second set injecting air downstream of the first set. The first set injects air at a compound angle, having both downward and tangential components, to create a reverse vortex flow, counter to the direction of flow of gas through the stack and also along the periphery of the stack interior surface. Air from the first set of holes pervents recirculation zones from forming and the attendant accumulation of particulate deposits on the wall of the stack and will also return to the plenum any particulate swept up in the gas entering the stack. The second set of holes injects air in the same direction as the gas in the stack to compensate for the pressure drop and to prevent the concentration of condensate in the stack. A set of sprayers, receiving water from a second conduit, is located downstream of the second set of holes and sprays water into the gas to further cool it.

  3. Stack gas treatment

    DOEpatents

    Reeves, Adam A.

    1977-04-12

    Hot stack gases transfer contained heat to a gravity flow of pebbles treated with a catalyst, cooled stacked gases and a sulfuric acid mist is withdrawn from the unit, and heat picked up by the pebbles is transferred to air for combustion or other process. The sulfuric acid (or sulfur, depending on the catalyst) is withdrawn in a recovery unit.

  4. ETR WASTE GAS STACK. ABOVE GROUND DUCTWORK AND ETR STACK, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    ETR WASTE GAS STACK. ABOVE GROUND DUCTWORK AND ETR STACK, CLOSER VIEW. PERSONNEL LADDER AND CIRCULAR WORK PLATFORM MIDWAY UP STACK. CAMERA FACES NORTH. INL NEGATIVE NO. HD42-7-2. Mike Crane, Photographer, 3/2004 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  5. Stack Gas Scrubber Makes the Grade

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1975

    1975-01-01

    Describes a year long test of successful sulfur dioxide removal from stack gas with a calcium oxide slurry. Sludge disposal problems are discussed. Cost is estimated at 0.6 mill per kwh not including sludge removal. A flow diagram and equations are included. (GH)

  6. Stacked rig refurbished for ultradeep gas drilling

    SciTech Connect

    Noevig, T.; Gutsche, W. )

    1995-01-09

    A heavy drilling rig, cold stacked for several years, recently underwent numerous structural, equipment, and computer upgrades for drilling ultradeep (8,000 m) gas wells in Germany. The technical improvements on the rig included supplementary installations and modifications to safety, quality, engineering, noise abatement, and environmental protection systems. With a maximal hook load of 700 tons, the drilling rig is one of the heaviest of its kind in Europe. The rig has a drilling depth range of 7,000--8,000 m, and the top drive system enables horizontal drilling. The paper describes the rig site, mast, top drive, substructure, draw works, power station, mud system, instrumentation, and other equipment.

  7. Simultaneous stack-gas scrubbing and waste water treatment

    NASA Technical Reports Server (NTRS)

    Poradek, J. C.; Collins, D. D.

    1980-01-01

    Simultaneous treatment of wastewater and S02-laden stack gas make both treatments more efficient and economical. According to results of preliminary tests, solution generated by stack gas scrubbing cycle reduces bacterial content of wastewater. Both processess benefit by sharing concentrations of iron.

  8. Removal of Sulfur from Natural Gas to Reduce Particulate Matter Emission from a Turbine Engine

    NASA Astrophysics Data System (ADS)

    Spang, Brent Loren

    The present work investigates the effect of natural gas fuel sulfur on particulate emissions from stationary gas turbine engines used for electricity generation. Fuel sulfur from standard line gas was scrubbed using a system of fluidized reactor beds containing a specially designed activated carbon purpose built for sulfur absorption. A sulfur injection system using sonic orifices was designed and constructed to inject methyl mercaptan into the scrubbed gas stream at varying concentrations. Using these systems, particulate emissions created by various fuel sulfur levels between 0 and 8.3 ppmv were investigated. Particulate samples were collected from a Capstone C65 microturbine generator system using a Horiba MDLT-1302TA micro dilution tunnel and analyzed using a Horiba MEXA-1370PM particulate analyzer. In addition, ambient air samples were collected to determine incoming particulate levels in the combustion air. The Capstone C65 engine air filter was also tested for particulate removal efficiency by sampling downstream of the filter. To further differentiate the particulate entering the engine in the combustion air from particulate being emitted from the exhaust stack, two high efficiency HEPA filters were installed to eliminate a large portion of incoming particulate. Variable fuel sulfur testing showed that there was a strong correlation between total particulate emission factor and fuel sulfur concentration. Using eleven variable sulfur tests, it was determined that an increase of 1 ppmv fuel sulfur will produce an increase of approximately 3.2 microg/m3 total particulate. Also, the correlation also predicted that, for this particular engine, the total particulate emission factor for zero fuel sulfur was approximately 19.1 microg/m3. With the EC and OC data removed, the correlation became 3.1 microg/m3 of sulfur particulate produced for each ppmv of fuel sulfur. The correlation also predicted that with no fuel sulfur present, 6.6 microg/m3 of particulate will

  9. Particulate hot gas stream cleanup technical issues

    SciTech Connect

    Pontius, D.H.; Snyder, T.R.

    1999-09-30

    The analyses of hot gas stream cleanup particulate samples and descriptions of filter performance studied under this contract were designed to address problems with filter operation that have been linked to characteristics of the collected particulate matter. One objective of this work was to generate an interactive, computerized data bank of the key physical and chemical characteristics of ash and char collected from operating advanced particle filters and to relate these characteristics to the operation and performance of these filters. The interactive data bank summarizes analyses of over 160 ash and char samples from fifteen pressurized fluidized-bed combustion and gasification facilities utilizing high-temperature, high pressure barrier filters.

  10. Method for removing particulate matter from a gas stream

    DOEpatents

    Postma, Arlin K.

    1984-01-01

    Particulate matter is removed from a stream of pressurized gas by directing the stream of gas upwardly through a bed of porous material, the porous bed being held in an open ended container and at least partially submerged in liquid. The passage of the gas through the porous bed sets up a circulation in the liquid which cleans the particulate matter from the bed.

  11. Simultaneous stack gas scrubbing wastewater purification

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Variations of a process for removing sulfur dioxide from stack gases and using it to treat municipal waste water are described. The once-through system lowers the pH of the scrubbing water from minor depressions to a pH of about 2.5 under certain conditions. A recycle system uses iron for catalytic oxidation of sulfurous acid to sulfuric acid allowing very large amounts of sulfur dioxide to be absorbed in a small portion of water. The partial recycle system uses municipal wastewater and iron as a scrubbing medium, followed by neutralization of the wastewater with lime to produce an iron hydroxide precipitation which, when removed, produces tertiary quality treated wastewater. The SO2 scrubber is described, test results are analyzed, and a preliminary capital cost estimate for the three processes is included.

  12. Process for off-gas particulate removal and apparatus therefor

    DOEpatents

    Carl, D.E.

    1997-10-21

    In the event of a breach in the off-gas line of a melter operation requiring closure of the line, a secondary vessel vent line is provided with a particulate collector utilizing atomization for removal of large particulates from the off-gas. The collector receives the gas containing particulates and directs a portion of the gas through outer and inner annular channels. The collector further receives a fluid, such as water, which is directed through the outer channel together with a second portion of the particulate-laden gas. The outer and inner channels have respective ring-like termination apertures concentrically disposed adjacent one another on the outer edge of the downstream side of the particulate collector. Each of the outer and inner channels curves outwardly away from the collector`s centerline in proceeding toward the downstream side of the collector. Gas flow in the outer channel maintains the fluid on the channel`s wall in the form of a ``wavy film,`` while the gas stream from the inner channel shears the fluid film as it exits the outer channel in reducing the fluid to small droplets. Droplets formed by the collector capture particulates in the gas stream by one of three mechanisms: impaction, interception or Brownian diffusion in removing the particulates. The particulate-laden droplets are removed from the fluid stream by a vessel vent condenser or mist eliminator. 4 figs.

  13. IET exhaust gas stack. Section, west elevation, foundation plan, access ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    IET exhaust gas stack. Section, west elevation, foundation plan, access ladder, airplane warning light. Ralph M. Parsons 902-5-ANP-712-S 433. Date: May 1954. Approved by INEEL Classification Office for public release. INEEL index code no. 035-0712-60-693-106984 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  14. Particulate Emissions from Gas Turbine Engines. Revision.

    DTIC Science & Technology

    1992-02-01

    with ferrocene additive) Particulate mass emissions from a J79-GE-IOB engine A-48 to A-64 Particulate mass emissions from a J52-P-6B engine A-65 to A...J79-CE-8D engine 4-9 1 with ferrocene additive (Summary of Files 34 through 45) 6 Particulate emissions from the ,J/7-G;E8f) engine 4 - 0l with... ferrocene additive (Summary of Files 46 and 47) 7 Particulate emissions from the J79-GE-8D engine 4-1i with ferrocene additive (Summary of Files 34 through

  15. Experimental analysis of internal gas flow configurations for a polymer electrolyte membrane fuel cell stack

    NASA Astrophysics Data System (ADS)

    Friedl, A.; Fraser, S. D.; Baumgartner, W. R.; Hacker, V.

    The internal gas distribution system utilised for supplying fresh reactants and removing reaction products from the individual cells of a fuel cell stack can be designed in a parallel, a serial or a mixture of parallel and serial gas flow configuration. In order to investigate the interdependence between the internal stack gas distribution configuration and single cell as well as overall stack performance, a small laboratory-scale fuel cell stack consisting of identical unit cells was subject to operation with different gas distribution configurations and different operating parameters. The current/voltage characteristics measured with the different gas distribution configurations are analysed and compared on unit cell- as well as on stack-level. The results show the significant impact of the internal stack gas distribution system on operation and performance of the individual unit cells and the overall stack.

  16. Rotary device for removing particulates from a gas stream

    NASA Technical Reports Server (NTRS)

    Collins, Jr., Earl R. (Inventor)

    1992-01-01

    A rotary particulate separator for removing particulates from a pressurized gas stream such as that emanating from a reactor vessel is disclosed which precharges the particles in the gas stream, and then utilizes the charge on the particles to induce them from the main flow path through an airblock and into the rotary particulate separator. The rotor of the rotary particulate separator has polarized plates which use a first charge opposite that on the charged particles to attract the particles as they enter the rotation chamber, and then use a second charge of the same polarity as the charge on the charged particles to release the particles into a control gas flow vortex which draws the particles radially inwardly into an exit aperture contained in the center of one of the rotor segments and out from the device. Pressure letdown devices are used to drop the pressure of both the control gas flow exiting the separator with the particles and the cleaned gas stream.

  17. Particulate exhaust emissions from an experimental combustor. [gas turbine engine

    NASA Technical Reports Server (NTRS)

    Norgren, C. T.; Ingebo, R. D.

    1975-01-01

    The concentration of dry particulates (carbon) in the exhaust of an experimental gas turbine combustor was measured at simulated takeoff operating conditions and correlated with the standard smoke-number measurement. Carbon was determined quantitatively from a sample collected on a fiberglass filter by converting the carbon in the smoke sample to carbon dioxide and then measuring the volume of carbon dioxide formed by gas chromatography. At a smoke of 25 (threshold of visibility of the smoke plume for large turbojets) the carbon concentration was 2.8 mg carbon/cu m exhaust gas, which is equivalent to an emission index of 0.17 g carbon/kg fuel.

  18. Particulate Hot Gas Stream Cleanup Technical Issues

    SciTech Connect

    Dorchak, T.P.; Pontiu, D.H.; Snyder, T.R.

    1996-12-31

    The nature of the collected ash has been identified as an issue creating barriers to the commercialization of advanced particle control technologies. Since most of the emphasis and extended operation of Hot Gas Stream Cleanup (HGCU) facilities have been with ceramic candle filters, problems with ash characteristics can be understood in terms of their effects on these control devices. This project is designed to identify the ways ash characteristics affect advanced particle control technologies, to construct and maintain a data base of HGCU ashes and their measured characteristics, and to relate these characteristics to the operation and performance of these facilities. The key characteristics of the collected ash are the morphology of the overall ash aggregate (porosity, geometry of the pores, specific surface area, etc.), and the cohesivity of the aggregate. Our data base currently comprises 242 ash samples from 12 combustion and gasification (HGCU) sources.

  19. PARTICULATE HOT GAS STREAM CLEANUP TECHNICAL ISSUES

    SciTech Connect

    1999-02-26

    This quarterly report describes technical activities performed under Contract No. DE-AC21-94MC31160. The analyses of hot gas stream cleanup (HGCU) ashes and descriptions of filter performance studied under Task 1 of this contract are designed to address problems with filter operation that are apparently linked to characteristics of the collected ash. This report includes a description of a device developed to harden a filter cake on a filter element so that the element and cake can subsequently be encapsulated in epoxy and studied in detail. This report also reviews the status of the HGCU data base of ash and char characteristics. Task 1 plans for the remainder of the project include characterization of additional samples collected during site visits to the Department of Energy/Southern Company Services Power Systems Development Facility (PSDF), encapsulation of an intact filter cake from the PSDF, and completion and delivery of the HGCU data bank. Task 2 of this project concerns the testing and failure analyses of new and used filter elements and filter materials. Task 2 work during the past quarter consisted of hoop tensile and axial compressive stress-strain responses of McDermott ceramic composite and hoop tensile testing of Techniweave candle filters as-manufactured and after exposure to the gasification environment.

  20. Workshop on Aerosols and Particulates from Aircraft Gas Turbine Engines

    NASA Technical Reports Server (NTRS)

    Wey, Chown Chou (Compiler)

    1999-01-01

    In response to the National Research Council (NRC) recommendations, the Workshop on Aerosols and Particulates from Aircraft Gas Turbine Engines was organized by the NASA Lewis Research Center and held on July 29-30, 1997 at the Ohio Aerospace Institute in Cleveland, Ohio. The objective is to develop consensus among experts in the field of aerosols from gas turbine combustors and engines as to important issues and venues to be considered. Workshop participants' expertise included engine and aircraft design, combustion processes and kinetics, atmospheric science, fuels, and flight operations and instrumentation.

  1. Measurement of Opacity and Particulate Emissions With an On-Stack Transmissometer

    ERIC Educational Resources Information Center

    Beutner, Heinz P.

    1974-01-01

    An on-stack transmissometer system, that is designed to provide a precision measurement of the opacity of visible emissions, is described. The sources of error in opacity measurements with regard to recent Environmental Protection Agency emission monitoring requirements and planned specifications are discussed. (Author/BT)

  2. Particulate Matter Stack Emission Compliance Test Procedure for Fuel Burning Units.

    ERIC Educational Resources Information Center

    West Virginia Air Pollution Control Commission, Charleston.

    This publication details the particulate matter emissions test procedure that is applicable for conducting compliance tests for fuel burning units required to be tested under Sub-section 7 of Regulation II (1972) as established by the state of West Virginia Air Pollution Control Commission. The testing procedure is divided into five parts:…

  3. Onset of stacking faults in InP nanowires grown by gas source molecular beam epitaxy

    NASA Astrophysics Data System (ADS)

    Cornet, D. M.; Mazzetti, V. G. M.; LaPierre, R. R.

    2007-01-01

    InP nanowires (NWs) were grown by gas source molecular beam epitaxy on InP (111)B substrates, using Au nanoparticles as a growth catalyst. The rod-shaped NWs exhibited hexagonal sidewall facets oriented along the {-211} family of crystal planes for all NW diameters, indicating minimal sidewall growth. Stacking faults, when present, were concentrated near the NW tips, while NWs with lengths less than 300nm were completely free of stacking faults.

  4. Evaluation of gas cooling for pressurized phosphoric acid fuel cell stacks

    NASA Technical Reports Server (NTRS)

    Farooque, M.; Skok, A. J.; Maru, H. C.; Kothmann, R. E.; Harry, R. W.

    1983-01-01

    Gas cooling is a more reliable, less expensive and a more simple alternative to conventional liquid cooling for heat removal from the phosphoric acid fuel cell (PAFC). The feasibility of gas cooling has already been demonstrated in atmospheric pressure stacks. This paper presents theoretical and experimental investigation of gas cooling for pressurized PAFC. Two approaches to gas cooling, Distributed Gas Cooling (DIGAS) and Separated Gas Cooling (SGC) were considered, and a theoretical comparison on the basis of cell performance indicated SGC to be superior to DIGAS. The feasibility of SGC was experimentally demonstrated by operating a 45-cell stack for 700 hours at pressure, and determining thermal response and the effect of other related parameters.

  5. Exposure assessment of particulates of diesel and natural gas fuelled buses in silico.

    PubMed

    Pietikäinen, Mari; Oravisjärvi, Kati; Rautio, Arja; Voutilainen, Arto; Ruuskanen, Juhani; Keiski, Riitta L

    2009-12-15

    Lung deposition estimates of particulate emissions of diesel and natural gas (CNG) fuelled vehicles were studied by using in silico methodology. Particulate emissions and particulate number size distributions of two Euro 2 petroleum based diesel buses and one Euro 3 gas bus were measured. One of the petroleum based diesel buses used in the study was equipped with an oxidation catalyst on the vehicle (DI-OC) while the second had a partial-DPF catalyst (DI-pDPF). The third bus used was the gas bus with an oxidation catalyst on the vehicle (CNG-OC). The measurements were done using a transient chassis dynamometer test cycle (Braunschweig cycle) and an Electric Low Pressure Impactor (ELPI) with formed particulates in the size range of 7 nm to 10 microm. The total amounts of the emitted diesel particulates were 88-fold for DI-OC and 57-fold for DI-pDPF compared to the total amount of emitted CNG particulates. Estimates for the deposited particulates were computed with a lung deposition model ICRP 66 using in-house MATLAB scripts. The results were given as particulate numbers and percentages deposited in five different regions of the respiratory system. The percentages of particulates deposited in the respiratory system were 56% for DI-OC, 51% for DI-pDPF and 77% for CNG-OC of all the inhaled particulates. The result shows that under similar conditions the total lung dose of particulates originating from petroleum diesel fuelled engines DI-OC and DI-pDPF was more than 60-fold and 35-fold, respectively, compared to the lung dose of particulates originating from the CNG fuelled engine. The results also indicate that a majority (35-50%) of the inhaled particulates emitted from the tested petroleum diesel and CNG engines penetrate deep into the unciliated regions of the lung where gas-exchange occurs.

  6. Optical backscatter probe for sensing particulate in a combustion gas stream

    SciTech Connect

    Parks, James E; Partridge, William P

    2013-05-28

    A system for sensing particulate in a combustion gas stream is disclosed. The system transmits light into a combustion gas stream, and thereafter detects a portion of the transmitted light as scattered light in an amount corresponding to the amount of particulates in the emissions. Purge gas may be supplied adjacent the light supply and the detector to reduce particles in the emissions from coating or otherwise compromising the transmission of light into the emissions and recovery of scattered light from the emissions.

  7. 40 CFR 92.117 - Gas meter or flow instrumentation calibration, particulate measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ENGINES Test Procedures § 92.117 Gas meter or flow instrumentation calibration, particulate measurement... practice. (2) Flow air through the calibration system at the sample flow rate used for particulate testing... standard device. (4) Calculate air flow at standard conditions as measured by both the standard device...

  8. 40 CFR 92.117 - Gas meter or flow instrumentation calibration, particulate measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ENGINES Test Procedures § 92.117 Gas meter or flow instrumentation calibration, particulate measurement... practice. (2) Flow air through the calibration system at the sample flow rate used for particulate testing... standard device. (4) Calculate air flow at standard conditions as measured by both the standard device...

  9. 40 CFR 92.117 - Gas meter or flow instrumentation calibration, particulate measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ENGINES Test Procedures § 92.117 Gas meter or flow instrumentation calibration, particulate measurement... practice. (2) Flow air through the calibration system at the sample flow rate used for particulate testing... standard device. (4) Calculate air flow at standard conditions as measured by both the standard device...

  10. 40 CFR 92.117 - Gas meter or flow instrumentation calibration, particulate measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ENGINES Test Procedures § 92.117 Gas meter or flow instrumentation calibration, particulate measurement... practice. (2) Flow air through the calibration system at the sample flow rate used for particulate testing... standard device. (4) Calculate air flow at standard conditions as measured by both the standard device...

  11. 40 CFR 92.117 - Gas meter or flow instrumentation calibration, particulate measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ENGINES Test Procedures § 92.117 Gas meter or flow instrumentation calibration, particulate measurement... practice. (2) Flow air through the calibration system at the sample flow rate used for particulate testing... standard device. (4) Calculate air flow at standard conditions as measured by both the standard device...

  12. 40 CFR 266.105 - Standards to control particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... standard cubic foot) after correction to a stack gas concentration of 7% oxygen, using procedures... particulate matter standard. (c) Oxygen correction. (1) Measured pollutant levels must be corrected for the amount of oxygen in the stack gas according to the formula: ER30SE99.027 Where: Pc is the...

  13. FACTORS INFLUENCING THE DEPOSITION OF A COMPOUND THAT PARTITIONS BETWEEN GAS AND PARTICULATE PHASES

    EPA Science Inventory

    How will atmospheric deposition behave for a compound when it reversibly sorbs between gas and atmospheric particulate phases? Two factors influence the answer. What physical mechanisms occur in the sorption process? What are the concentration and composition of atmospheric par...

  14. Effect on combined cycle efficiency of stack gas temperature constraints to avoid acid corrosion

    NASA Technical Reports Server (NTRS)

    Nainiger, J. J.

    1980-01-01

    To avoid condensation of sulfuric acid in the gas turbine exhaust when burning fuel oils contaning sulfur, the exhaust stack temperature and cold-end heat exchanger surfaces must be kept above the condensation temperature. Raising the exhaust stack temperature, however, results in lower combined cycle efficiency compared to that achievable by a combined cycle burning a sulfur-free fuel. The maximum difference in efficiency between the use of sulfur-free and fuels containing 0.8 percent sulfur is found to be less than one percentage point. The effect of using a ceramic thermal barrier coating (TBC) and a fuel containing sulfur is also evaluated. The combined-cycle efficiency gain using a TBC with a fuel containing sulfur compared to a sulfur-free fuel without TBC is 0.6 to 1.0 percentage points with air-cooled gas turbines and 1.6 to 1.8 percentage points with water-cooled gas turbines.

  15. Observation of exclusively π-stacked heterodimer of indole and hexafluorobenzene in the gas phase

    NASA Astrophysics Data System (ADS)

    Kumar, Sumit; Das, Aloke

    2013-09-01

    In this study, the structure of the indole . . . hexafluorobenzene dimer has been investigated in the gas phase by using resonant two photon ionzation (R2PI) and IR-UV double resonance spectroscopy combined with quantum chemistry calculations. We have confirmed the presence of exclusively π-stacked structure of the dimer from both experimental and theoretical IR spectra in the N-H stretching region. Observation of a single stable structure of the dimer has also been verified through 3D potential energy surface scan of the π-stacked dimer by varying the parallel displacement of the hexafluorobenzene unit simultaneously along the major and minor axes of the indole moiety. π-stacking interaction is present very often between the tryptophan and phenylalanine residues in proteins. But this interaction has not been observed earlier in the gas phase experiment by studying indole . . . benzene dimer because the N-H group of indole predominately directs towards the N-H . . . π hydrogen bonded T-shaped structure. The chosen molecular systems in this study not only rule out the possibility of the formation of the N-H . . . π bound T-shaped dimer but also enable the determination of the structure by probing the N-H group. The π-stacked indole . . . hexafluorobenzene dimer has a unique structure where the center of the hexafluorobenznene ring is aligned with the center of the shared bond of the indole ring. Our work provides useful insight in designing unnatural proteins having strong π-stacking interaction between the tryptophan and phenylalanine residues.

  16. DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS-FIRED COMBUSTION SYSTEMS

    SciTech Connect

    Glenn C. England

    2004-10-20

    In 1997, the United States Environmental Protection Agency (EPA) promulgated new National Ambient Air Quality Standards (NAAQS) for particulate matter, including for the first time particles with aerodynamic diameter smaller than 2.5 micrometers ({micro}m) referred to as PM2.5. PM2.5 in the atmosphere also contributes to reduced atmospheric visibility, which is the subject of existing rules for siting emission sources near Class 1 areas and new Regional Haze rules. There are few existing data regarding emissions and characteristics of fine aerosols from oil, gas and power generation industry combustion sources, and the information that is available is generally outdated and incomplete. Traditional stationary source air emission sampling methods tend to underestimate or overestimate the contribution of the source to ambient aerosols because they do not properly account for primary aerosol formation, which occurs after the gases leave the stack. Primary aerosol includes both filterable particles that are solid or liquid aerosols at stack temperature plus those that form as the stack gases cool through mixing and dilution processes in the plume downwind of the source. These deficiencies in the current methods can have significant impacts on regulatory decision-making. PM2.5 measurement issues were extensively reviewed by the American Petroleum Institute (API) (England et al., 1998), and it was concluded that dilution sampling techniques are more appropriate for obtaining a representative particulate matter sample from combustion systems for determining PM2.5 emission rate and chemical speciation. Dilution sampling is intended to collect aerosols including those that condense and/or react to form solid or liquid aerosols as the exhaust plume mixes and cools to near-ambient temperature immediately after the stack discharge. These techniques have been widely used in recent research studies. For example, Hildemann et al. (1994) and McDonald et al. (1998) used filtered

  17. Adjustment of the flue gas path in small combustion appliances with regard to particulate matter reduction

    NASA Astrophysics Data System (ADS)

    Sulovcová, Katarína; Jandačka, Jozef; Nosek, Radovan

    2014-08-01

    Concentration of solid particles in ambient atmosphere is increasing in many countries nowadays. Particulate matter pollution in higher concentration has harmful impact on human and animal health. Source of particulate matter are not only industry and traffic. Small heat sources with biomass combustion, especially during winter heating season, are also significant producer of particulate matter emission. There is a huge importance to decrease quantities of solid particles which are getting into the atmosphere in every region of their production in order to decrease environmental pollution and improve air quality. The ability of flue gas emission elimination can influence future using of biomass combustion. Therefore effective and affordable solutions are searching for. The paper deals with the reduction of particulate matter in small heat source with biomass combustion by modification of geometric parameters in flue gas path.

  18. 40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Gas meter or flow instrumentation... Procedures § 86.120-94 Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement. (a) Sampling for particulate, methanol and formaldehyde emissions requires the use of gas...

  19. Predicting saturation of gas hydrates using pre-stack seismic data, Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Shelander, Dianna; Dai, Jianchun; Bunge, George

    2010-03-01

    A promising method for gas hydrates exploration incorporates pre-stack seismic inversion data, elastic properties modeling, and seismic interpretation to predict saturation of gas hydrates ( Sgh). The technology can be modified slightly and used for predicting hydrate concentrations in shallow arctic locations as well. Examples from Gulf of Mexico Walker Ridge (WR) and Green Canyon (GC) protraction areas illustrate how Sgh was derived and used to support the selection of well locations to be drilled for gas hydrates in sand reservoirs by the Chevron-led Joint Industry Project (JIP) Leg II cruise in 2009. Concentrations of hydrates were estimated through the integration of seismic inversion of carefully conditioned pre-stack data, seismic stratigraphic interpretation, and shallow rock property modeling. Rock property trends were established by applying principles of rock physics and shallow sediment compaction, constrained by regional geological knowledge. No nearby sonic or density logs were available to define the elastic property trends in the zone of interest. Sgh volumes were generated by inverting pre-stack data to acoustic and shear impedance (PI and SI) volumes, and then analyzing deviations from modeled impedance trends. In order to enhance the quality of the inversion, we stress the importance of maximizing the signal to noise ratio of the offset data by conditioning seismic angle gathers prior to inversion. Seismic interpretation further plays an important role by identifying false anomalies such as hard, compact strata, which can produce apparent high Sgh values, and by identifying the more promising strata and structures for containing the hydrates. This integrated workflow presents a highly promising methodology, appropriate for the exploration of gas hydrates.

  20. Three-dimensional Numerical Simulation of Gas-particulate Flow around Breathing Human and Particulate Inhalation

    NASA Astrophysics Data System (ADS)

    Shimazaki, Yasuhiro; Okubo, Masaaki; Yamamoto, Toshiaki

    2006-05-01

    It is important to predict the environment around the breathing human because inhalation of virus (avian influenza, SARS) is recently severe worldwide problem, and air pollution caused by diesel emission particle (DEP) and asbestos attract a great deal of attention. In the present study, three-dimensional numerical simulation was carried out to predict unsteady flows around a breathing human and how suspended particulate matter (SPM, diameter˜1 μm) reaches the human nose in inhalation and exhalation. In the calculation, we find out smaller breathing angle and the closer distance between the human nose and pollutant region are effective in the inhalation of SPM.

  1. Boiler briquette coal versus raw coal: Part I--Stack gas emissions.

    PubMed

    Ge, S; Bai, Z; Liu, W; Zhu, T; Wang, T; Qing, S; Zhang, J

    2001-04-01

    Stack gas emissions were characterized for a steam-generating boiler commonly used in China. The boiler was tested when fired with a newly formulated boiler briquette coal (BB-coal) and when fired with conventional raw coal (R-coal). The stack gas emissions were analyzed to determine emission rates and emission factors and to develop chemical source profiles. A dilution source sampling system was used to collect PM on both Teflon membrane filters and quartz fiber filters. The Teflon filters were analyzed gravimetrically for PM10 and PM2.5 mass concentrations and by X-ray fluorescence (XRF) for trace elements. The quartz fiber filters were analyzed for organic carbon (OC) and elemental carbon (EC) using a thermal/optical reflectance technique. Sulfur dioxide was measured using the standard wet chemistry method. Carbon monoxide was measured using an Orsat combustion analyzer. The emission rates of the R-coal combustion (in kg/hr), determined using the measured stack gas concentrations and the stack gas emission rates, were 0.74 for PM10, 0.38 for PM2.5, 20.7 for SO2, and 6.8 for CO, while those of the BB-coal combustion were 0.95 for PM10, 0.30 for PM2.5, 7.5 for SO2, and 5.3 for CO. The fuel-mass-based emission factors (in g/kg) of the R-coal, determined using the emission rates and the fuel burn rates, were 1.68 for PM10, 0.87 for PM2.5, 46.7 for SO2, and 15 for CO, while those of the BB-coal were 2.51 for PM10, 0.79 for PM2.5, 19.9 for SO2, and 14 for CO. The task-based emission factors (in g/ton steam generated) of the R-coal, determined using the fuel-mass-based emission factors and the coal/steam conversion factors, were 0.23 for PM10, 0.12 for PM2.5, 6.4 for SO2, and 2.0 for CO, while those of the BB-coal were 0.30 for PM10, 0.094 for PM2.5, 2.4 for SO2, and 1.7 for CO. PM10 and PM2.5 elemental compositions are also presented for both types of coal tested in the study.

  2. Boiler Briquette Coal versus Raw Coal: Part I-Stack Gas Emissions.

    PubMed

    Ge, Su; Bai, Zhipeng; Liu, Weili; Zhu, Tan; Wang, Tongjian; Qing, Sheng; Zhang, Junfeng

    2001-04-01

    Stack gas emissions were characterized for a steam-generating boiler commonly used in China. The boiler was tested when fired with a newly formulated boiler briquette coal (BB-coal) and when fired with conventional raw coal (R-coal). The stack gas emissions were analyzed to determine emission rates and emission factors and to develop chemical source profiles. A dilution source sampling system was used to collect PM on both Teflon membrane filters and quartz fiber filters. The Teflon filters were analyzed gravimetrically for PM10 and PM2.5 mass concentrations and by X-ray fluorescence (XRF) for trace elements. The quartz fiber filters were analyzed for organic carbon (OC) and elemental carbon (EC) using a thermal/optical reflectance technique. Sulfur dioxide was measured using the standard wet chemistry method. Carbon monoxide was measured using an Orsat combustion analyzer. The emission rates of the R-coal combustion (in kg/hr), determined using the measured stack gas concentrations and the stack gas emission rates, were 0.74 for PM10, 0.38 for PM25, 20.7 for SO2, and 6.8 for CO, while those of the BB-coal combustion were 0.95 for PM10, 0.30 for PM2 5, 7.5 for SO2, and 5.3 for CO. The fuel-mass-based emission factors (in g/kg) of the R-coal, determined using the emission rates and the fuel burn rates, were 1.68 for PM10, 0.87 for PM25, 46.7 for SO2, and 15 for CO, while those of the BB-coal were 2.51 for PM10, 0.79 for PM2.5, 19.9 for SO2, and 14 for CO. The task-based emission factors (in g/ton steam generated) of the R-coal, determined using the fuel-mass-based emission factors and the coal/ steam conversion factors, were 0.23 for PM10, 0.12 for PM2.5, 6.4 for SO2, and 2.0 for CO, while those of the BB-coal were 0.30 for PM10, 0.094 for PM2.5, 2.4 for SO2, and 1.7 for CO. PM10 and PM2.5 elemental compositions are also presented for both types of coal tested in the study.

  3. Apparatus for removal of particulate matter from gas streams

    DOEpatents

    Smith, Peyton L.; Morse, John C.

    2000-01-01

    An apparatus for the removal of particulate matter from the gaseous product stream of an entrained flow coal gasifier which apparatus includes an initial screen, an intermediate screen which is aligned with the direction of flow of the gaseous product stream and a final screen transversely disposed to the flow of gaseous product and which apparatus is capable of withstanding at least a pressure differential of about 10 psi (68.95 kPa) or greater at the temperatures of the gaseous product stream.

  4. Speciation of Total Organic Gas and Particulate Matter Emissions from Onroad Vehicles in the Next Version of MOVES

    EPA Science Inventory

    Calculation of organic gas measures used in MOVES (total hydrocarbons, methane, non-methane hydrocarbons, volatile organic compounds, non-methane organic gases, and total organic gases). Incorporation of speciation within MOVES to produce total organic gas and particulate matte...

  5. Aerodynamic improvement of the assembly through which gas conduits are taken into a smoke stack by simulating gas flow on a computer

    NASA Astrophysics Data System (ADS)

    Prokhorov, V. B.; Fomenko, M. V.; Grigor'ev, I. V.

    2012-06-01

    Results from computer simulation of gas flow motion for gas conduits taken on one and two sides into the gas-removal shaft of a smoke stack with a constant cross section carried out using the SolidWorks and FlowVision application software packages are presented.

  6. 40 CFR 86.120-94 - Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Gas meter or flow instrumentation... Procedures § 86.120-94 Gas meter or flow instrumentation calibration; particulate, methanol and formaldehyde... or flow instrumentation to determine flow through the particulate filters, methanol impingers...

  7. An indirect method of measuring gas- and particulate-phase velocities of shock-induced dusty-gas flows

    NASA Astrophysics Data System (ADS)

    Gottlieb, James J.

    1992-03-01

    A method of indirectly measuring the temporally varying velocities of both the particulate and gas phases in the nonequilibrium region of a shock wave moving at constant speed in a dusty-gas mixture is described. This method is implemented by using experimental data from shock-induced air flows containing glass beads 40 microns in diameter in a dusty-gas shock-tube facility featuring a large horizontal channel 197 mm high by 76 mm wide with a special dust-injection device. Simultaneous measurements of the shock-front speed with time-of-arrival gauges, particulate concentration by light extinctiometry, and combined particulate concentration and gas density by beta-ray absorption are used in conjunction with two mass conservation laws to provide these indirect two-phase velocity measurements. Direct measurements of the particulate-phase velocity by laser-Doppler velocimetry are also presented for comparison, and the capability of the indirect velocity-measurement method is assessed.

  8. Electrochemical cell stack assembly

    DOEpatents

    Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2010-06-22

    Multiple stacks of tubular electrochemical cells having a dense electrolyte disposed between an anode and a cathode preferably deposited as thin films arranged in parallel on stamped conductive interconnect sheets or ferrules. The stack allows one or more electrochemical cell to malfunction without disabling the entire stack. Stack efficiency is enhanced through simplified gas manifolding, gas recycling, reduced operating temperature and improved heat distribution.

  9. Probing the gas content of radio galaxies through H I absorption stacking

    NASA Astrophysics Data System (ADS)

    Geréb, K.; Morganti, R.; Oosterloo, T. A.

    2014-09-01

    Using the Westerbork Synthesis Radio Telescope, we carried out shallow H i absorption observations of a flux-selected (S1.4 GHz > 50 mJy) sample of 93 radio active galactic nuclei (AGN), which have available SDSS (Sloan Digital Sky Survey) redshifts between 0.02 < z < 0.23. Our main goal is to study the gas properties of radio sources down to S1.4 GHz flux densities not systematically explored before using, for the first time, stacking of absorption spectra of extragalactic H i. Despite the shallow observations, we obtained a direct detection rate of ~29%, comparable with deeper studies of radio galaxies. Furthermore, detections are found at every S1.4 GHz flux level, showing that H i absorption detections are not biased toward brighter sources. The stacked profiles of detections and non-detections reveal a clear dichotomy in the presence of H i, with the 27 detections showing an average peak τ = 0.02 corresponding to N(H i) ~(7.4 ± 0.2) × 1018 (Tspin/cf) cm-2, while the 66 non-detections remain undetected upon stacking with a peak optical depth upper limit τ < 0.002 corresponding to N(H i) < (2.26 ± 0.06) × 1017 (Tspin/cf) cm-2 (using a FWHM of 62 kms-1, derived from the mean width of the detections). Separating the sample into compact and extended radio sources increases the detection rate, optical depth, and FWHM for the compact sample. The dichotomy for the stacked profiles of detections and non-detections still holds between these two groups of objects. We argue that orientation effects connected to a disk-like distribution of the H i can be partly responsible for the dichotomy that we see in our sample. However, orientation effects alone cannot explain all the observational results, and some of our galaxies must be genuinely depleted of cold gas. A fraction of the compact sources in the sample are confirmed by previous studies as likely young radio sources (compact steep spectrum and gigahertz peaked spectrum sources). These show an even higher

  10. Particulate matter, gaseous and particulate polycyclic aromatic hydrocarbons (PAHs) in an urban traffic tunnel of China: Emission from on-road vehicles and gas-particle partitioning.

    PubMed

    Liu, Ying; Gao, Yi; Yu, Na; Zhang, Chenkai; Wang, Siyao; Ma, Limin; Zhao, Jianfu; Lohmann, Rainer

    2015-09-01

    Traffic vehicles are a main source of polycyclic aromatic hydrocarbon (PAH) emission in urban area. It is vital to understand PAH gas-particle partitioning in real traffic environment and assess PAH vehicular emission factors in developing China. Concentrations of particulate matter, carbonaceous products, gaseous and particulate PAHs were measured during 2011-2012 in a road tunnel of Shanghai, China. Time variation of them reflected basic traffic operation of the tunnel. PAHs approached equilibrium between gas and particle phases and the partitioning was predicted better by a dual sorption model combining absorption into organic matter and adsorption onto black carbon. The influence of black carbon adsorption on the partitioning behavior of PAHs was important. The difference in isomer ratios of gaseous and particulate PAHs was attributed to PAH contributions from different traffic-related PAHs sources. Real-world vehicle emission factors of gaseous and particulate PAHs were quantified based on fuel burned model and vehicle kilometer traveled model.

  11. Gas and particulate phase products from the ozonolysis of acenaphthylene

    NASA Astrophysics Data System (ADS)

    Riva, Matthieu; Healy, Robert M.; Tomaz, Sophie; Flaud, Pierre-Marie; Perraudin, Emilie; Wenger, John C.; Villenave, Eric

    2016-10-01

    Polycyclic aromatic hydrocarbons (PAHs) are recognized as important secondary organic aerosol (SOA) precursors in the urban atmosphere. In this work, the gas-phase ozonolysis of acenaphthylene was investigated in an atmospheric simulation chamber using a proton transfer reaction time-of-flight-mass spectrometer (PTR-TOF-MS) and an aerosol time-of-flight-mass spectrometer (ATOFMS) for on-line characterization of the oxidation products in the gas and particle phases, respectively. SOA samples were also collected on filters and analyzed by ultra performance liquid chromatography/electrospray ionization high-resolution quadrupole time-of-flight mass spectrometry (UPLC/ESI-HR-QTOFMS) and gas chromatography/electron impact ionization-mass spectrometry (GC/EI-MS). The major gas-phase products included a range of oxygenated naphthalene derivatives such as 1,8-naphthalic anhydride, naphthalene 1,8-dicarbaldehyde and naphthaldehyde, as well as a secondary ozonide. Possible reaction mechanisms are proposed for the formation of these products and favoured pathways have been suggested. Many of these products were also found in the particle phase along with a range of oligomeric compounds. The same range of gas and particle phase products was observed in the presence and absence of excess cyclohexane, an OH scavenger, indicating that OH radical production from the ozonolysis of acenaphthylene is negligible. SOA yields in the range 23-37% were determined and indicate that acenaphthylene ozonolysis may contribute to part of the SOA observed in urban areas.

  12. Gas and Particulate Sampling of Airborne Polycyclic Aromatic Compounds

    SciTech Connect

    Lane, D.A.; Gundel, L.A.

    1995-10-01

    The denuder surfaces of the gas and particle (GAP) sampler (developed at the Atmospheric Environment Service of Environment Canada) have been modified by coating with XAD-4 resin, using techniques developed at Lawrence Berkeley National Laboratory (LBNL) for the lower capacity integrated organic vapor/particle sampler (IOVPS). The resulting high capacity integrated organic gas and particle sampler (IOGAPS) has been operated in ambient air at 16.7 L min{sup -1} for a 24-hour period in Berkeley, California, USA. Simultaneous measurements were made at the same collection rate with a conventional sampler that used a filter followed by two sorbent beds. Gas and particle partition measurements were determined for 13 polycyclic aromatic hydrocarbons (PAH) ranging from 2-ring to 6-ring species. The IOGAPS indicated a higher particle fraction of these compounds than did the conventional sampler, suggesting that the conventional sampler suffered from 'blow-off' losses from the particles collected on the filter.

  13. Formation of Secondary Particulate Matter by Reactions of Gas Phase Hexanal with Sulfate Aerosol Particles

    NASA Astrophysics Data System (ADS)

    Zhang, J.

    2003-12-01

    The formation of secondary particulate matter from the atmospheric oxidation of organic compounds can significantly contribute to the particulate burden, but the formation of organic secondary particulate matter is poorly understood. One way of producing organic secondary particulate matter is the oxidation of hydrocarbons with seven or more carbon atoms to get products with low vapor pressure. However, several recent reports suggest that relatively low molecular weight carbonyls can enter the particle phase by undergoing heterogeneous reactions. This may be a very important mechanism for the formation of organic secondary particulate matter. Atmospheric aldehydes are important carbonyls in the gas phase, which form via the oxidation of hydrocarbons emitted from anthropogenic and biogenic sources. In this poster, we report the results on particle growth by the heterogeneous reactions of hexanal. A 5 L Continuous Stirred Tank Reactor (CSTR) is set up to conduct the reactions in the presence of seed aerosol particles of deliquesced ammonia bisulfate. Hexanal is added into CSTR by syringe pump, meanwhile the concentrations of hexanal are monitored with High Pressure Liquid Chromatograph (HPLC 1050). A differential Mobility Analyzer (TSI 3071) set to an appropriate voltage is employed to obtain monodisperse aerosols, and another DMA associated with a Condensation Nuclear Counter (TSI 7610) is used to measure the secondary particle size distribution by the reaction in CSTR. This permits the sensitive determination of particle growth due to the heterogeneous reaction, very little growth occurs when hexanal added alone. Results for the simultaneous addition of hexanal and alcohols will also be presented.

  14. On the method of indirectly measuring gas and particulate phase velocities in shock induced dusty-gas flows

    NASA Astrophysics Data System (ADS)

    Lock, G. D.

    A method of indirectly measuring the temporally varying velocities of the gas and particulate phases in the nonequilibrium region of a shock wave moving at constant speed in a dusty-gas flow is described, and this method is assessed by using experimental data from shock-induced air flows containing 40-micron-diameter glass beads in a dusty-gas shock-tube facility featuring a large horizontal channel (19.7-cm by 7.6-cm in cross section). Simultaneous measurements of the shock-front speed with time-of-arrival gauges, particle concentration by light extinctiometry, and gas-particle mixture density by beta-ray absorption are used in conjunction with two mass conservation laws to obtain the indirect velocity measurements of both phases. A second indirect measurement of the gas-phase velocity is obtained when the gas pressure is simultaneously recorded along with the particle concentration and shock-front speed when used in conjunction with the conservation of mixture momentum. Direct measurements of the particulate-phase velocity by laser-Doppler velocimetry are also presented as a means of assessing the indirect velocity measurement method.

  15. Trace gas and particulate emissions from biomass burning in temperate ecosystems

    NASA Technical Reports Server (NTRS)

    Cofer, Wesley R., III; Levine, Joel S.; Winstead, Edward L.; Stocks, Brian J.

    1991-01-01

    Emissions measured from fires in graminoid wetlands, Mediterranean chaparrals, and boreal forests, suggest that such ecosystemic parameters as fuel size influence combustion emissions in ways that are broadly predictable. The degree of predictability is most noticeable when wetland fire-related results are compared with boreal forest emissions; the inorganic fraction of the particulate emissions is close in composition irrespective of the ecosystem. It is found that both aerosol and trace gas emissions are influenced by the phase of combustion.

  16. Assessment of the Losses Due to Self Absorption by Mass Loading on Radioactive Particulate Air Stack Sample Filters

    SciTech Connect

    Smith, Brian M.; Barnett, J. Matthew; Ballinger, Marcel Y.

    2011-01-18

    This report discusses the effect of mass loading of a membrane filter on the self absorption of radioactive particles. A relationship between mass loading and percent loss of activity is presented. Sample filters were collected from Pacific Northwest National Laboratory (PNNL) facilities in order to analyze the current self absorption correction factor of 0.85 that is being used for both alpha and beta particles. Over an eighteen month period from February 2009 to July 2010, 116 samples were collected and analyzed from eight different building stacks in an effort coordinated by the Effluent Management group. Eleven unused filters were also randomly chosen to be analyzed in order to determine background radiation. All of these samples were collected and analyzed in order to evaluate the current correction factor being used.

  17. High capacity gas storage in corrugated porous graphene with a specific surface area-lossless tightly stacking manner.

    PubMed

    Ning, Guoqing; Xu, Chenggen; Mu, Liang; Chen, Guangjin; Wang, Gang; Gao, Jinsen; Fan, Zhuangjun; Qian, Weizhong; Wei, Fei

    2012-07-11

    We report for the first time an experimental investigation of gas storage in porous graphene with nanomeshes. High capacity methane storage (236 v(STP)/v) and a high selectivity to carbon dioxide adsorption were obtained in the nanomesh graphene with a high specific surface area (SSA) and a SSA-lossless tightly stacking manner.

  18. Analysis of benzo(a)pyrene in airborne particulates by gas chromatography

    NASA Technical Reports Server (NTRS)

    Luedecke, E.

    1976-01-01

    A routine method was developed to measure benzo(a)pyrene in airborne particulates. Samples were collected on a filter and the organic portion was extracted with cyclohexane. The polynuclear hydrocarbon (PNHC) fraction was separated from the aliphatics by column chromatography. An internal standard was added to the extract and a portion of it was injected into a gas chromatograph. Although the gas chromatographic method has often been reported in the literature, satisfactory separation of benzo(a)pyrene and benzo(e)pyrene has not been achieved. With the introduction of a nematic liquid crystal as the stationary phase good separation is now possible.

  19. Porphyrin π-stacking in a heme protein scaffold tunes gas ligand affinity.

    PubMed

    Weinert, Emily E; Phillips-Piro, Christine M; Marletta, Michael A

    2013-10-01

    The role of π-stacking in controlling redox and ligand binding properties of porphyrins has been of interest for many years. The recent discovery of H-NOX domains has provided a model system to investigate the role of porphyrin π-stacking within a heme protein scaffold. Removal of a phenylalanine-porphyrin π-stack dramatically increased O2, NO, and CO affinities and caused changes in redox potential (~40mV) without any structural changes. These results suggest that small changes in redox potential affect ligand affinity and that π-stacking may provide a novel route to engineer heme protein properties for new functions.

  20. Requirements for very high power electron beam systems for utility stack gas treatment

    NASA Astrophysics Data System (ADS)

    Williams, K.; Frutiger, W. A.; Hiley, J.; Nablo, S. V.

    Energetic electrons in gas cause the formation of very reactive free radicals, ions, and excited-state molecules. These can react either with each other, or with oxygen and water in the system, or with some intentionally added chemical component and, thereby, produce removable compounds. Fuel economies and an increasing global interest in improving the environment, have resulted in a resurgence of interest in using very high power electron beam systems to reduce stack gas pollutants (SO 2, NO x, etc.), a process examined at low power levels in the last decade at JAERI. Increasing industrial demands for large width (greater than 2 meters), high dose rate (1 megarad at 1500 meters/minute) electron processors has led to significant advances in high power systems over the past several years. Selfshielded systems capable of up to 1000 mA at 300 kV are now in commercial use. The total electron beam requirements for fossil fuel fired power plants with generating capacities below 500 MWe can be met by a reasonable number of these state-of-the-art 300 kilowatt modules. Electron beam modules with power levels approaching 1 megawatt may ultimately be necessary to provide economy of scale for generating capacities higher than this, unless significant breakthroughs are made in enhancing the formation of stable removable compounds. This paper presents some of the results from the 300 kV, 180 kW electron beam pilot installation in Karlsruhe, West Germany ∗ along with a description of the state-of-the-art 300 kW electron processors. The requirements for very high power electron beam systems approaching 1 MW are discussed and some ideas for optimizing total electron beam system costs through the enhanced formation of stable removable compounds described.

  1. DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS FIRED COMBUSTION SYSTEMS

    SciTech Connect

    Glenn England; Oliver Chang; Stephanie Wien

    2002-02-14

    This report provides results from the second year of this three-year project to develop dilution measurement technology for characterizing PM2.5 (particles with aerodynamic diameter smaller than 2.5 micrometers) and precursor emissions from stationary combustion sources used in oil, gas and power generation operation. Detailed emission rate and chemical speciation tests results for a gas turbine, a process heater, and a commercial oil/gas fired boiler are presented. Tests were performed using a research dilution sampling apparatus and traditional EPA methods. A series of pilot tests were conducted to identify the constraints to reduce the size of current research dilution sampler for future stack emission tests. Based on the test results, a bench prototype compact dilution sampler developed and characterized in GE EER in August 2002.

  2. Hot particulate removal and desulfurization results from the METC integrated gasification and hot gas cleanup facility

    SciTech Connect

    Rockey, J.M.

    1995-06-01

    The Morgantown Energy Technology Center (METC) is conducting experimental testing using a 10-inch diameter fluid-bed gasifier (FBG) and modular hot gas cleanup rig (MGCR) to develop advanced methods for removing contaminants in hot coal gasifier gas streams for commercial development of integrated gasification combined-cycle (IGCC) power systems. The program focus is on hot gas particulate removal and desulfurization technologies that match the temperatures and pressures of the gasifier, cleanup system, and power generator. The purpose of this poster is to present the program objectives and results of the work conducted in cooperation with industrial users and vendors to meet the vision for IGCC of reducing the capital cost per kilowatt to $1050 and increasing the plant efficiency to 52% by the year 2010.

  3. Quenching of Particle-Gas Combustible Mixtures Using Electric Particulate Suspension (EPS) and Dispersion Methods

    NASA Technical Reports Server (NTRS)

    Colver, Gerald M.; Goroshin, Samuel; Lee, John H. S.

    2001-01-01

    A cooperative study is being carried out between Iowa State University and McGill University. The new study concerns wall and particle quenching effects in particle-gas mixtures. The primary objective is to measure and interpret flame quenching distances, flammability limits, and burning velocities in particulate suspensions. A secondary objective is to measure particle slip velocities and particle velocity distribution as these influence flame propagation. Two suspension techniques will be utilized and compared: (1) electric particle suspension/EPS; and (2) flow dispersion. Microgravity tests will permit testing of larger particles and higher and more uniform dust concentrations than is possible in normal gravity.

  4. Development of techniques to characterize particulates emitted from gas turbine exhausts

    NASA Astrophysics Data System (ADS)

    Johnson, M. P.; Hilton, M.; Waterman, D. R.; Black, J. D.

    2003-07-01

    Particles emitted from aircraft play a role in the formation of contrails and it is essential to characterize them to understand the physical and chemical processes that are happening. Current methods for measuring aircraft particulate emissions study the reflectance of samples collected in filter papers. A series of experiments to more fully characterize particulates has been performed on a small-scale gas turbine engine. An intrusive sampling system conforming to current ICAO regulations for aircraft emissions was used with a scanning mobility particle sizer (SMPS). Non-intrusive measurements were made using laser induced incandescence (LII) and samples were taken from the exhaust to analyse using a transmission electron microscope. Results obtained from different techniques showed good agreement with each other. As engine power conditions increased, both the SMPS and LII indicated that the mass of soot had decreased. Differences were observed between measurements of diluted and undiluted samples. The mean particle size decreased with dilution but the size distribution became bi-modal. The study has shown how significant the sampling environment is for measuring particulates and careful techniques need to be used to ensure that accurate, consistent results can be obtained.

  5. Three-dimensional conductive networks based on stacked SiO2@graphene frameworks for enhanced gas sensing.

    PubMed

    Huang, Da; Yang, Zhi; Li, Xiaolin; Zhang, Liling; Hu, Jing; Su, Yanjie; Hu, Nantao; Yin, Guilin; He, Dannong; Zhang, Yafei

    2017-01-07

    Graphene is an ideal candidate for gas sensing due to its excellent conductivity and large specific surface areas. However, it usually suffers from sheet stacking, which seriously debilitates its sensing performance. Herein, we demonstrate a three-dimensional conductive network based on stacked SiO2@graphene core-shell hybrid frameworks for enhanced gas sensing. SiO2 spheres are uniformly encapsulated by graphene oxide (GO) through an electrostatic self-assembly approach to form SiO2@GO core-shell hybrid frameworks, which are reduced through thermal annealing to establish three-dimensional (3D) conductive sensing networks. The SiO2 supported 3D conductive graphene frameworks reveal superior sensing performance to bare reduced graphene oxide (RGO) films, which can be attributed to their less agglomeration and larger surface area. The response value of the 3D framework based sensor for 50 ppm NH3 and 50 ppm NO2 increased 8 times and 5 times, respectively. Additionally, the sensing performance degradation caused by the stacking of the sensing materials is significantly suppressed because the graphene layers are separated by the SiO2 spheres. The sensing performance decays by 92% for the bare RGO films when the concentration of the sensing material increases 8 times, while there is only a decay of 25% for that of the SiO2@graphene core-shell hybrid frameworks. This work provides an insight into 3D frameworks of hybrid materials for effectively improving gas sensing performance.

  6. Real-Time Characterization of Particle and Gas Phase Diesel Emissions - Understanding the Influence of a Diesel Particulate Filter

    NASA Astrophysics Data System (ADS)

    Cross, E. S.; Sappok, A.; Carrasquillo, A. J.; Onasch, T. B.; Fortner, E.; Jayne, J.; Wong, V.; Worsnop, D. R.; Kroll, J. H.

    2010-12-01

    Diesel engine emissions constitute an important source of particulate black carbon (BC) and gas phase organics in the atmosphere. Particles composed of black carbon absorb incoming solar radiation having a net positive radiative forcing effect on the climate. Black carbon also has major air quality implications as BC particles from combustion sources are often coated with poly-aromatic hydrocarbons (PAHs), and are generally emitted in higher concentrations close to population centers. Regulations of diesel emissions target the mass of particulate matter (PM) and concentration of volatile gas phase organic compounds (VOC) produced. A third, potentially important component of diesel exhaust, is low volatility organic compounds (LVOC). Both the VOCs and LVOCs can lead to the formation of ultrafine particles (via homogeneous nucleation) and secondary organic aerosols (via oxidation). Recent development of mass spectrometric techniques to measure particulate black carbon and gas phase organics provide the opportunity to quantify and chemically characterize diesel emissions in real-time. Measurements of both the particulate and gas phase emissions from a medium-duty diesel engine will be presented. The experimental apparatus includes a diesel particulate filter (DPF) integrated in the exhaust line, which is a requirement for all 2007 and newer on-road diesel engines in the U.S. Measurements taken over the regeneration cycle of the DPF provide insight into how this after-treatment technology influences the gas phase and particle phase composition of the emissions. Gas phase measurements were made with a newly developed Total Gas-Phase Organic (TGO) instrument. Particulate species were characterized with a Soot Particle Aerosol Mass Spectrometer (SP-AMS). The combined utility of the TGO and SP-AMS instruments for emissions characterization studies will be demonstrated.

  7. An automatic isokinetic sampler for particulate emissions from aircraft gas turbine engines. Final report Feb 75-Jun 78

    SciTech Connect

    Dehne, H.

    1980-01-01

    An automated isokinetic sampler for evaluating particulate emissions from aircraft gas turbine engines was designed, constructed and tested. The sampler is capable of collecting the particulate mass emitted by an aircraft gas turbine at the exit plane (non-afterburner operation) for gravimetric measurements and permits simultaneous on-line particle size distribution measurements to be performed. The particulate is collected on a fiber glass filter for gravimetric measurement. The size distribution is determined by conditioning the gas turbine exhaust gases and passing them through a mobility particulate size distribution analyzer. The sampler has two-axis traverse capability and a maximum sampling capability of 226 1/min (8 scfm). Test data are automatically recorded. Control of the sampler is by means of 12-bit microprocessor. Preliminary tests were performed at the Naval Air Rework Facility, Alameda, California, at various construction stages of the sampler to evaluate its performance and to measure the effects of fuel additives on particulate emissions on a TF41 gas turbine engine.

  8. Evaluation of a Combined Cyclone and Gas Filtration System for Particulate Removal in the Gasification Process

    SciTech Connect

    Rizzo, Jeffrey J.

    2010-04-30

    The Wabash gasification facility, owned and operated by sgSolutions LLC, is one of the largest single train solid fuel gasification facilities in the world capable of transforming 2,000 tons per day of petroleum coke or 2,600 tons per day of bituminous coal into synthetic gas for electrical power generation. The Wabash plant utilizes Phillips66 proprietary E-Gas (TM) Gasification Process to convert solid fuels such as petroleum coke or coal into synthetic gas that is fed to a combined cycle combustion turbine power generation facility. During plant startup in 1995, reliability issues were realized in the gas filtration portion of the gasification process. To address these issues, a slipstream test unit was constructed at the Wabash facility to test various filter designs, materials and process conditions for potential reliability improvement. The char filtration slipstream unit provided a way of testing new materials, maintenance procedures, and process changes without the risk of stopping commercial production in the facility. It also greatly reduced maintenance expenditures associated with full scale testing in the commercial plant. This char filtration slipstream unit was installed with assistance from the United States Department of Energy (built under DOE Contract No. DE-FC26-97FT34158) and began initial testing in November of 1997. It has proven to be extremely beneficial in the advancement of the E-Gas (TM) char removal technology by accurately predicting filter behavior and potential failure mechanisms that would occur in the commercial process. After completing four (4) years of testing various filter types and configurations on numerous gasification feed stocks, a decision was made to investigate the economic and reliability effects of using a particulate removal gas cyclone upstream of the current gas filtration unit. A paper study had indicated that there was a real potential to lower both installed capital and operating costs by implementing a char

  9. Separation of particulate from flue gas of fossil fuel combustion and gasification

    DOEpatents

    Yang, Wen-Ching; Newby, Richard A.; Lippert, Thomas E.

    1997-01-01

    The gas from combustion or gasification of fossil fuel contains flyash and other particulate. The flyash is separated from the gas in a plurality of standleg moving granular-bed filter modules. Each module includes a dipleg through which the bed media flows into the standleg. The bed media forms a first filter bed having an upper mass having a first frusto-conical surface in a frusto-conical member at the entrance to the standleg and a lower mass having a second frusto-conical surface of substantially greater area than the first surface after it passes through the standleg. A second filter media bed may be formed above the first filter media bed. The gas is fed tangentially into the module above the first surface. The flyash is captured on the first frusto-conical surface and within the bed mass. The processed gas flows out through the second frusto-conical surface and then through the second filter bed, if present. The bed media is cleaned of the captured flyash and recirculated to the moving granular bed filter. Alternatively, the bed media may be composed of the ash from the combustion which is pelletized to form agglomerates. The ash flows through the bed only once; it is not recycled.

  10. Separation of particulate from flue gas of fossil fuel combustion and gasification

    DOEpatents

    Yang, W.C.; Newby, R.A.; Lippert, T.E.

    1997-08-05

    The gas from combustion or gasification of fossil fuel contains fly ash and other particulates. The fly ash is separated from the gas in a plurality of standleg moving granular-bed filter modules. Each module includes a dipleg through which the bed media flows into the standleg. The bed media forms a first filter bed having an upper mass having a first frusto-conical surface in a frusto-conical member at the entrance to the standleg and a lower mass having a second frusto-conical surface of substantially greater area than the first surface after it passes through the standleg. A second filter media bed may be formed above the first filter media bed. The gas is fed tangentially into the module above the first surface. The fly ash is captured on the first frusto-conical surface and within the bed mass. The processed gas flows out through the second frusto-conical surface and then through the second filter bed, if present. The bed media is cleaned of the captured fly ash and recirculated to the moving granular bed filter. Alternatively, the bed media may be composed of the ash from the combustion which is pelletized to form agglomerates. The ash flows through the bed only once; it is not recycled. 11 figs.

  11. Black carbon particulate matter emission factors for buoyancy-driven associated gas flares.

    PubMed

    McEwen, James D N; Johnson, Matthew R

    2012-03-01

    Flaring is a technique used extensively in the oil and gas industry to burn unwanted flammable gases. Oxidation of the gas can preclude emissions of methane (a potent greenhouse gas); however, flaring creates other pollutant emissions such as particulate matter (PM) in the form of soot or black carbon (BC). Currently available PM emissionfactors for flares were reviewed and found to be questionably accurate, or based on measurements not directly relevant to open-atmosphere flares. In addition, most previous studies of soot emissions from turbulent diffusion flames considered alkene or alkyne based gaseous fuels, and few considered mixed fuels in detail and/or lower sooting propensity fuels such as methane, which is the predominant constituent of gas flared in the upstream oil and gas industry. Quantitative emission measurements were performed on laboratory-scale flares for a range of burner diameters, exit velocities, and fuel compositions. Drawing from established standards, a sampling protocol was developed that employed both gravimetric analysis of filter samples and real-time measurements of soot volume fraction using a laser-induced incandescence (LII) system. For the full range of conditions tested (burner inner diameter [ID] of 12.7-76.2 mm, exit velocity 0.1-2.2 m/sec, 4- and 6-component methane-based fuel mixtures representative of associated gas in the upstream oil industry), measured soot emission factors were less than 0.84 kg soot/10(3) m3 fuel. A simple empirical relationship is presented to estimate the PM emission factor as a function of the fuel heating value for a range of conditions, which, although still limited, is an improvement over currently available emission factors.

  12. Characterization of particulate matter emissions from a current technology natural gas engine.

    PubMed

    Thiruvengadam, Arvind; Besch, Marc C; Yoon, Seungju; Collins, John; Kappanna, Hemanth; Carder, Daniel K; Ayala, Alberto; Herner, Jorn; Gautam, Mridul

    2014-07-15

    Experiments were conducted to characterize the particulate matter (PM)-size distribution, number concentration, and chemical composition emitted from transit buses powered by a USEPA 2010 compliant, stoichiometric heavy-duty natural gas engine equipped with a three-way catalyst (TWC). Results of the particle-size distribution showed a predominant nucleation mode centered close to 10 nm. PM mass in the size range of 6.04 to 25.5 nm correlated strongly with mass of lubrication-oil-derived elemental species detected in the gravimetric PM sample. Results from oil analysis indicated an elemental composition that was similar to that detected in the PM samples. The source of elemental species in the oil sample can be attributed to additives and engine wear. Chemical speciation of particulate matter (PM) showed that lubrication-oil-based additives and wear metals were a major fraction of the PM mass emitted from the buses. The results of the study indicate the possible existence of nanoparticles below 25 nm formed as a result of lubrication oil passage through the combustion chamber. Furthermore, the results of oxidative stress (OS) analysis on the PM samples indicated strong correlations with both the PM mass calculated in the nanoparticle-size bin and the mass of elemental species that can be linked to lubrication oil as the source.

  13. An analysis of extinction coefficients of particles and water moisture in the stack after flue gas desulfurization at a coal-fired power plant.

    PubMed

    Tu, Wen-Fu; Lin, Jenn-Der; Wu, Yee-Lin

    2011-08-01

    Two important factors that affect in-stack opacity--light extinction by emitted particles and that by water moisture after a flue gas desulfurization (FGD) unit--are investigated. The mass light extinction coefficients for particles and water moisture, k(p) and k(w), respectively, were determined using the Lambert-Beer law of opacity with a nonlinear least-squares regression method. The estimated k(p) and k(w) values vary from 0.199 to 0.316 m2/g and 0.000345 to 0.000426 m2/g, respectively, and the overall mean estimated values are 0.229 and 0.000397 m2/g, respectively. Although k(w) is 3 orders of magnitude smaller than k(p), experimental results show that the effect on light extinction by water moisture was comparable to that by particles because of the existence of a considerable mass of water moisture after a FGD unit. The mass light extinction coefficient was also estimated using Mie theory with measured particle size distributions and a complex refractive index of 1.5-ni for fly ash particles. The k(p) obtained using Mie theory ranges from 0.282 to 0.286 m2/g and is slightly greater than the averaged estimated k(p) of 0.229 m2/g from measured opacity. The discrepancy may be partly due to a difference in the microstructure of the fly ash from the assumption of solid spheres because the fly ash may have been formed as spheres attached with smaller particles or as hollow spheres that contained solid spheres. Previously reported values of measured k(p) obtained without considering the effects of water moisture are greater than that obtained in this study, which is reasonable because it reflects the effect of extinction by water moisture in the flue gas. Additionally, the moisture absorbed by particulate matter, corresponding to the effect of water moisture on the particulates, was clarified and found to be negligible.

  14. Comparison of different gas-phase mechanisms and aerosol modules for simulating particulate matter formation.

    PubMed

    Kim, Youngseob; Couvidat, Florian; Sartelet, Karine; Seigneur, Christian

    2011-11-01

    The effects of two gas-phase chemical kinetic mechanisms, Regional Atmospheric Chemistry Mechanism version 2 (RACM2) and Carbon-Bond 05 (CB05), and two secondary organic aerosol (SOA) modules, the Secondary Organic Aerosoi Model (SORGAM) and AER/EPRI/Caltech model (AEC), on fine (aerodynamic diameter < or =2.5 microm) particulate matter (PM2.5) formation is studied. The major sources of uncertainty in the chemistry of SOA formation are investigated. The use of all major SOA precursors and the treatment of SOA oligomerization are found to be the most important factors for SOA formation, leading to 66% and 60% more SOA, respectively. The explicit representation of high-NO, and low-NOx gas-phase chemical regimes is also important with increases in SOA of 30-120% depending on the approach used to implement the distinct SOA yields within the gas-phase chemical kinetic mechanism; further work is needed to develop gas-phase mechanisms that are fully compatible with SOA formation algorithms. The treatment of isoprene SOA as hydrophobic or hydrophilic leads to a significant difference, with more SOA being formed in the latter case. The activity coefficients may also be a major source of uncertainty, as they may differ significantly between atmospheric particles, which contain a myriad of SOA, primary organic aerosol (POA), and inorganic aerosol species, and particles formed in a smog chamber from a single precursor under dry conditions. Significant interactions exist between the uncertainties of the gas-phase chemistry and those of the SOA module.

  15. Concept Learning versus Problem Solving: Evaluating a Threat to the Validity of a Particulate Gas Law Question

    ERIC Educational Resources Information Center

    Sanger, Michael J.; Vaughn, C. Kevin; Binkley, David A.

    2013-01-01

    Three different samples of students were asked to answer five multiple-choice questions concerning the properties of a sample of helium gas (particle speed, state of matter, sample volume, sample pressure, and particle distribution), including a particulate question first used by Nurrenbern and Pickering (particle distribution). In the first…

  16. Analysis and modeling of PEM fuel cell stack performance: Effect of in situ reverse water gas shift reaction and oxygen bleeding

    NASA Astrophysics Data System (ADS)

    Karimi, G.; Li, Xianguo

    In this study the performance of a polymer electrolyte membrane (PEM) fuel cell stack is analyzed with a mathematical model when the stack operates on hydrocarbon reformate gas as the anode feed stream. It is shown that the effect of carbon dioxide dilution of the hydrogen dominated reformate gas has a minimal impact on the stack performance. However, the CO-poisoning effect due to the in situ reverse water gas shift reaction in the anode feed stream could have a very serious adverse impact on the stack performance, especially at high current densities. Thermodynamic calculations indicate that the equilibrium concentrations of CO could be as high as 100 ppm, generated by the in situ reverse water gas shift reaction, under the typical conditions of PEM fuel cell operation; and are influenced by the stack operating temperature and water content of the reformate anode feed. This CO-poisoning of the stack performance is shown mitigated effectively by introducing about 0.5-1% oxygen to the anode feed.

  17. Post-test analysis of 20kW molten carbonate fuel cell stack operated on coal gas. Final report, August 1993--February 1996

    SciTech Connect

    1996-05-01

    A 20kW carbonate fuel cell stack was operated with coal gas for the first time in the world. The stack was tested for a total of 4,000 hours, of which 3,900 hours of testing was conducted at the Louisiana Gasification Technology Incorporated, Plaquemine, Louisiana outdoor site. The operation was on either natural gas or coal gas and switched several times without any effects, demonstrating duel fuel capabilities. This test was conducted with 9142 kJ/m{sup 3} (245 Btu/cft) coal gas provided by a slipstream from Destec`s entrained flow, slagging, slurry-fed gasifier equipped with a cold gas cleanup subsystem. The stack generated up to 21 kW with this coal gas. Following completion of this test, the stack was brought to Energy Research Corporation (ERC) and a detailed post-test analysis was conducted to identify any effects of coal gas on cell components. This investigation has shown that the direct fuel cell (DFC) can be operated with properly cleaned and humidified coal-as, providing stable performance. The basic C direct fuel cell component materials are stable and display normal stability in presence of the coal gas. No effects of the coal-borne contaminants are apparent. Further cell testing at ERC 1 17, confirmed these findings.

  18. Characteristics of a Four-Nozzle, Slotted Short Mixing Stack with Shroud, Gas Eductor System.

    DTIC Science & Technology

    1982-03-01

    expansion factor Ffr Wall skin- friction force (lbf) gc Proportionality factor in Newton’s Second Law ( = 32.174 ibm-ft/lbf-sec ) h Enthalpy (Btu/lbm) k...flow rate (Ibm/sec) Y Expansion factor Dimensionless Groupings A* Ratio of secondary flow area to primary flow area AR Area ratio f Friction factor K...the conventional pipe friction factor term based on the bulk-average flow velocity Um and the mixing stack wall area Aw . The following parameters

  19. Ion beam analyses of particulate matter in exhaust gas of a ship diesel engine

    NASA Astrophysics Data System (ADS)

    Furuyama, Yuichi; Fujita, Hirotsugu; Taniike, Akira; Kitamura, Akira

    2011-12-01

    There is an urgent need to reduce emission of the particulate matter (PM) in the exhaust gas from ship diesel engines causing various health hazards and serious environmental pollution. Usually the heavy fuel oil (HFO) for ships is of low quality, and contains various kinds of impurities. Therefore, the emission of PM along with exhaust gas from ship diesel engines is one of the most serious environmental issues. However, the PM fundamental properties are not well known. Therefore, it is important to perform elemental analysis of the PM. The HFO contains sulfur with a relatively high concentration of a few percent. It is important to make quantitative measurements of sulfur in the PM, because this element is poisonous for the human body. In the present work, PM samples were collected from exhaust gas of a test engine, and RBS and PIXE analyses were applied successfully to quantitative analysis of the PM samples. The RBS analysis enabled quantitative analysis of sulfur and carbon in the collected PM, while heavier elements such as vanadium and iron were analyzed quantitatively with the PIXE analysis. It has been found that the concentration ratio of sulfur to carbon was between 0.007 and 0.012, and did not strongly depend on the output power of the engine. The S/ C ratio is approximately equal to the original composition of the HFO used in the present work, 0.01. From the known conversion ratio 0.015 of sulfur in the HFO to sulfates, the conversion ratio of carbon in the HFO to the PM is found to be 0.01-0.02 by the RBS measurements. On the other hand, the PIXE analysis revealed a vanadium enrichment of one order of magnitude in the PM.

  20. Method for monitoring stack gases for uranium activity

    DOEpatents

    Beverly, Claude R.; Ernstberger, Harold G.

    1988-01-01

    A method for monitoring the stack gases of a purge cascade of a gaseous diffusion plant for uranium activity. A sample stream is taken from the stack gases and contacted with a volume of moisture-laden air for converting trace levels of uranium hexafluoride, if any, in the stack gases into particulate uranyl fluoride. A continuous strip of filter paper from a supply roll is passed through this sampling stream to intercept and gather any uranyl fluoride in the sampling stream. This filter paper is then passed by an alpha scintillation counting device where any radioactivity on the filter paper is sensed so as to provide a continuous monitoring of the gas stream for activity indicative of the uranium content in the stack gases.

  1. Method for monitoring stack gases for uranium activity

    DOEpatents

    Beverly, C.R.; Ernstberger, E.G.

    1985-07-03

    A method for monitoring the stack gases of a purge cascade of gaseous diffusion plant for uranium activity. A sample stream is taken from the stack gases and contacted with a volume of moisture-laden air for converting trace levels of uranium hexafluoride, if any, in the stack gases into particulate uranyl fluoride. A continuous strip of filter paper from a supply roll is passed through this sampling stream to intercept and gather any uranyl fluoride in the sampling stream. This filter paper is then passed by an alpha scintillation counting device where any radioactivity on the filter paper is sensed so as to provide a continuous monitoring of the gas stream for activity indicative of the uranium content in the stack gases. 1 fig.

  2. 23. Brick coke quencher, brick stack, metal stack to right, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. Brick coke quencher, brick stack, metal stack to right, coke gas pipe to left; in background, BOF building, limestone piles, Levy's Slag Dump. Looking north/northwest - Rouge Steel Company, 3001 Miller Road, Dearborn, MI

  3. Gas/solid particulate phthalic esters (PAEs) in Masson pine (Pinus massoniana L.) needles and rhizosphere surface soils.

    PubMed

    Wang, Wen-xin; Fan, Chinbay Q

    2014-07-15

    Phthalic acid esters (PAEs) are used in many branches of industry and are produced in huge amounts throughout the world. An investigation on particulate- and gas-phase distribution of PAEs has been conducted between January 2011 and December 2012 in Nanjing (China). Masson pine (Pinus massoniana L.) needles and rhizosphere surface soils were sampled from urban to suburban/remote sites, to investigate the pine needle/soil distribution of PAEs. The results showed that the average total PAE concentration (gas+particle) was 97.0ngm(-3). The six PAE congeners considered predominantly existed in the gas phase and the average contribution of gas phase to total PAEs ranged from 75.0% to 89.1%. The PAE concentrations in rhizosphere soils and pine needles were positively correlated with their particulate- and gas-phase concentrations, respectively, which suggested that surface soils accumulated PAEs mainly through gravity deposition of particles and pine needle stomata absorbed PAEs mainly from the gas phase. The gas/particle partitioning (KP) and soil-pine needle ratio (Rs/n) were determined. Experimentally determined KP values correlated well with the subcooled liquid vapor pressures (PL). A set of interesting relationships of logRs/n-logKP-logPL was employed to explain the experimental findings of PAEs deposition to surface soils and to needles. This data set offered a unique perspective into the influence that Rs/n played in KP and correlated with PL.

  4. Including impacts of particulate emissions on marine ecosystems in life cycle assessment: the case of offshore oil and gas production.

    PubMed

    Veltman, Karin; Huijbregts, Mark A J; Rye, Henrik; Hertwich, Edgar G

    2011-10-01

    Life cycle assessment is increasingly used to assess the environmental performance of fossil energy systems. Two of the dominant emissions of offshore oil and gas production to the marine environment are the discharge of produced water and drilling waste. Although environmental impacts of produced water are predominantly due to chemical stressors, a major concern regarding drilling waste discharge is the potential physical impact due to particles. At present, impact indicators for particulate emissions are not yet available in life cycle assessment. Here, we develop characterization factors for 2 distinct impacts of particulate emissions: an increased turbidity zone in the water column and physical burial of benthic communities. The characterization factor for turbidity is developed analogous to characterization factors for toxic impacts, and ranges from 1.4 PAF (potentially affected fraction) · m(3) /d/kg(p) (kilogram particulate) to 7.0 x 10³ [corrected] for drilling mud particles discharged from the rig. The characterization factor for burial describes the volume of sediment that is impacted by particle deposition on the seafloor and equals 2.0 × 10(-1) PAF · m(3) /d/kg(p) for cutting particles. This characterization factor is quantified on the basis of initial deposition layer characteristics, such as height and surface area, the initial benthic response, and the recovery rate. We assessed the relevance of including particulate emissions in an impact assessment of offshore oil and gas production. Accordingly, the total impact on the water column and on the sediment was quantified based on emission data of produced water and drilling waste for all oil and gas fields on the Norwegian continental shelf in 2008. Our results show that cutting particles contribute substantially to the total impact of offshore oil and gas production on marine sediments, with a relative contribution of 55% and 31% on the regional and global scale, respectively. In contrast, the

  5. Gas-phase and particulate products from the atmospheric degradation of an isoxazole fungicide.

    PubMed

    Tortajada-Genaro, Luis Antonio; Borrás, Esther; Muñoz, Amalia

    2013-08-01

    The isoxazole structure is present in several pesticides. However, there is a lack of information about its degradation products after the release to the atmosphere. The main atmospheric reactions of hymexazol (5-methylisoxazol-3-ol), selected as representative model, were investigated at a large outdoor simulation chamber. The predominant products of atmospheric degradations were gaseous nitrogen derivates (nitric acid, nitrogen dioxide, nitrogen oxide, nitrous acid, and peroxyacetylnitrate), ozone, and small oxygenated compounds (formic acid, formaldehyde, and methylglyoxal). The aerosol yields were lower than 5%, and an OH rate-dependence was observed in the nucleation, particle growth, and size distribution. Also, the chemical composition of minor multi-oxygenated products was studied for OH-photo-oxidations. More than 20 products were detected in the gas or particulate phase. The most abundant were heterocyclic cleavage products with C4-chain and oxygenated moieties at positions 1 and 3, such as 3,4-dioxobutanoic acid, 3-oxobutanoic acid, and 3-oxobutanal. The suggested reaction pathway is the opening of heterocycle ring by the cleavage of N-O bond and C-N bond, releasing nitrogen oxides.

  6. Nonlinear empirical model of gas humidity-related voltage dynamics of a polymer-electrolyte-membrane fuel cell stack

    NASA Astrophysics Data System (ADS)

    Meiler, M.; Andre, D.; Schmid, O.; Hofer, E. P.

    suitable experimental setup to apply fast variations of gas humidity is introduced and is used to investigate a 10 cell PEMFC stack under various operation conditions. Using methods like stepwise multiple-regression a good mathematical description with reduced free parameters is achieved.

  7. Simultaneous determination of aliphatic and aromatic amines in ambient air and airborne particulate matters by gas chromatography-mass spectrometry

    NASA Astrophysics Data System (ADS)

    Akyüz, Mehmet

    2008-05-01

    A gas chromatography-mass spectrometry (GC-MS) method has been proposed for the simultaneous determination of aliphatic and aromatic amines in ambient air and airborne particulate matters (PMs). The method includes collection of the particulate matters (PM2.5 and PM10) using dichotomous Partisol 2025 sampler followed by extraction of the compounds into acidic solution, and pre-concentration of the compounds by percolating the air samples through the acidic solution, then ion-pair extraction of amines with bis-2-ethylhexylphosphate and derivatisation with isobutyl chloroformate prior to their GC-MS analysis in both electron impact and positive and negative ion chemical ionisation mode as their isobutyloxycarbonyl (isoBOC) derivatives. In the present study, ambient air and airborne particulate samples collected in Zonguldak province during summer and winter times of 2006-2007 were analysed for aliphatic and aromatic amines by the proposed method and the method was shown to be suitable for the simultaneous determination of these compounds at the levels of pg m-3 in air and airborne particulate samples. The seasonal distributions of bioactive amines in concentrations in ambient air and airborne PMs were evaluated as they are significant for the estimation of their effects on the environment and human health. The concentration levels of water soluble amines fluctuate significantly within a year with higher means and peak concentrations, probably due to the increased emissions from coal-fired domestic and central heating, in the winter times compared to the summer times. The results indicated that the relative amine content in particulates modulates with molecular mass and time of the year and the relative amine content especially in fine fractions of inhalable airborne particulates increases with the molecular mass of species but decreases with temperature.

  8. Sampling of power plant stacks for air toxic emissions: Topical report for Phases 1 and 2

    SciTech Connect

    1995-02-21

    Under contract with the US Department of Energy (DE-AC22-92PCO0367), Pittsburgh Energy Technology Center, Radian Corporation has conducted a test program to collect and analyze size-fractionated stack gas particulate samples for selected inorganic hazardous air pollutants (HAPS). Specific goals of the program are (1) the collection of one-gram quantities of size-fractionated stack gas particulate matter for bulk (total) and surface chemical charactization, and (2) the determination of the relationship between particle size, bulk and surface (leachable) composition, and unit load. The information obtained from this program identifies the effects of unit load, particle size, and wet FGD system operation on the relative toxicological effects of exposure to particulate emissions.

  9. Simultaneous particulates, NO sub x , SO sub x removal from flue gas by all solid-state electrochemical technology

    SciTech Connect

    Cook, W.J.; Cornell, L.P.; Keyvani, M.; Neyman, M.

    1989-07-21

    The objective is to develop an all solid-state electrochemical technology to control SO{sub x}, NO{sub x}, and particulate emissions from coal combustion flue gases. It is based on a solid-state, electrochemical reactor which reduces NOx and SO{sub 2} to nitrogen, sulfur, and oxygen. The solid electrolyte is a high surface area ceramic oxide-ion conductor such as a stabilized zirconia or ceria. The cell electrodes may be of various electronically conductive materials such as porous, high surface area nickel, silver, or gold. Work was performed in two areas, electrocatalyst preparation and testing and particulate control tests. Transition metal oxide electrocatalysts were tested by applying the electrocatalyst along with gold electrodes to a stabilized ceria solid electrolyte disk and measuring the reduction of NO and SO{sub 2} in gas mixtures containing 0 to 4% oxygen while a voltage was applied to the disk. The high temperature particulate control test apparatus was installed and flyash tests were done. The efficiency of high temperature particulate filters was also tested. 2 refs., 10 figs.

  10. Study of medical isotope production facility stack emissions and noble gas isotopic signature using automatic gamma-spectra analysis platform

    NASA Astrophysics Data System (ADS)

    Zhang, Weihua; Hoffmann, Emmy; Ungar, Kurt; Dolinar, George; Miley, Harry; Mekarski, Pawel; Schrom, Brian; Hoffman, Ian; Lawrie, Ryan; Loosz, Tom

    2013-04-01

    The nuclear industry emissions of the four CTBT (Comprehensive Nuclear-Test-Ban Treaty) relevant radioxenon isotopes are unavoidably detected by the IMS along with possible treaty violations. Another civil source of radioxenon emissions which contributes to the global background is radiopharmaceutical production companies. To better understand the source terms of these background emissions, a joint project between HC, ANSTO, PNNL and CRL was formed to install real-time detection systems to support 135Xe, 133Xe, 131mXe and 133mXe measurements at the ANSTO and CRL 99Mo production facility stacks as well as the CANDU (CANada Deuterium Uranium) primary coolant monitoring system at CRL. At each site, high resolution gamma spectra were collected every 15 minutes using a HPGe detector to continuously monitor a bypass feed from the stack or CANDU primary coolant system as it passed through a sampling cell. HC also conducted atmospheric monitoring for radioxenon at approximately 200 km distant from CRL. A program was written to transfer each spectrum into a text file format suitable for the automatic gamma-spectra analysis platform and then email the file to a server. Once the email was received by the server, it was automatically analysed with the gamma-spectrum software UniSampo/Shaman to perform radionuclide identification and activity calculation for a large number of gamma-spectra in a short period of time (less than 10 seconds per spectrum). The results of nuclide activity together with other spectrum parameters were saved into the Linssi database. This database contains a large amount of radionuclide information which is a valuable resource for the analysis of radionuclide distribution within the noble gas fission product emissions. The results could be useful to identify the specific mechanisms of the activity release. The isotopic signatures of the various radioxenon species can be determined as a function of release time. Comparison of 133mXe and 133Xe activity

  11. Greenhouse Gas and Particulate Emissions and Impacts from Cooking Technologies in Africa

    NASA Astrophysics Data System (ADS)

    Kammen, D. M.; Bailis, R.; Kituyi, E.; Ezzati, M.

    2003-12-01

    In much of Africa, the largest fraction of energy consumption occurs within the residential sector and is derived primarily from woodfuels burned in simple stoves with poor combustion characteristics. Many of the products of incomplete combustion (PICs) are damaging to human health, particularly when they are concentrated in poorly ventilated indoor environments. Incomplete combustion also has potentially harmful impacts on the climate. Prevalent PICs include methane, a potent greenhouse gas (GHG) that is among the pollutants subject to controls under the Kyoto Protocol as well as carbon monoxide (CO), non-methane hydrocarbons (NMHCs) and particulate matter (PM), which can all have an effect on climate, but are not subject to controls under Kyoto. In addition, when woodfuels are used at a rate that reduces standing stocks of trees over the medium or long term, the CO2 released by combustion also has an impact. The choice of stove and fuel technology can have a significant impact on the emission of GHGs as well as on human exposure to health damaging pollutants. In this paper we analyze the emissions of different household energy technologies on a life-cycle basis. We use emission factors to estimate the emissions associated with production, distribution and end-use of common household fuels and assess the likely impacts of these emissions on public health and the global environment. We focus largely on charcoal, a popular fuel in many sub-Saharan African countries. Charcoal is produced by heating wood in the absence of sufficient air for complete combustion to occur. This process removes moisture and most of the volatile compounds. The compounds driven off in the process consist of condensable tars as well as many gaseous hydrocarbons, including ~40 g CH4 per kg of charcoal produced. Combining upstream and end-use emissions, every meal cooked with charcoal has 2-10 times the global warming effect of cooking the same meal with firewood and 5-12 times the effect of

  12. Testing of a Shrouded, Short Mixing Stack Gas Eductor Model Using High Temperature Primary Flow.

    DTIC Science & Technology

    1982-10-01

    underground pipe to building 249. Air enters the test facility through a vertical standpipe which contains an eight inch butterfly valve in parallel with a...bypass globe valve (Figure 6). The butterfly valve is - .- normally closed, flow through the bypass valve only being 48 q sufficient to operate the gas...eight inch butterfly valve and enters a short section of piping which is used by other departments to supply various experiments. The second arm of the

  13. Simultaneous particulates, NO sub x , SO sub x removal from flue gas by all solid-state electrochemical technology

    SciTech Connect

    Cook, W.J.; Hossain, M.S.; Neyman, M. ); Gordon, A.Z. )

    1988-04-20

    The IGR emission control technology controls SOx, NOx, and particulate emissions from coal combustion flue gases. It is based on a solid-state, flow-through, electrochemical reactor which reduces NOx and SO{sub 2} to nitrogen, sulfur, and oxygen. The cell electrolyte is a solid electrolyte, normally a high surface area ceramic oxide-ion conductor. Three tasks were active during this quarter, Task (1) Development of 10 Cubic Feet/Min High Surface Area Electrochemical Reactors, Task (2) Procurement, Construction and Debugging of the Electrochemical Reactors and Particulate Removal System and Task (3) Electrocatalyst Preparation and Screening Studies. Task (3) is the screening of electrocatalysts for high oxygen overpotential and low SO{sub 2} and NO{sub x} overpotential. Electrochemical measurements were made with oxide ion conducting ceramic disks in nitric oxide and sulfur dioxide gas mixtures. 2 refs., 10 figs.

  14. Simultaneous particulates, NO sub x , SO sub x removal from flue gas by all solid-state electrochemcial technology

    SciTech Connect

    Cook, W.J.; Keyvani, M.; Neyman, M. ); Gordon, A.Z. )

    1989-05-22

    The IGR Process emission control technology controls SO{sub 2}/NO{sub x}, and particulate emissions from coal combustion flue gases. The technology uses an electrochemical solid-state reactor which converts SO{sub 2} and NO{sub x} to S, N{sub 2}, and O{sub 2}. The cell electrolyte is a solid electrolyte, namely a high surface area ceramic oxide-ion conductor. Tasks this quarter include: (1) Procurement, Construction and Debugging of the Electrochemical Reactors and Particulate Removal System; (2) Reactor Operation on SO{sub 2}/NO{sub x} Spiked Gas Streams; and (3) Electrocatalysts Preparation and Screening Studies. In Task (1) the particulate control test apparatus has been completely installed and flyash tests have begun. During the tests a voltage is applied across the solid electrolyte and the current is monitored while flyash passes through the cell. In Task (1) electrochemical measurements were made with oxide ion conducting ceramic disks in gases containing NO and SO{sub 2}. In Task (3) the electrochemical measurements are being made using four electrocatalysts in gases containing NO, SO{sub 2}, and oxygen. 3 refs., 4 figs., 2 tabs.

  15. Simultaneous particulates, NO sub x , SO sub x removal from flue gas by all solid-state electrochemical technology

    SciTech Connect

    Cook, W.J.; Hossain, M.S.; Keyvani, M.; Neyman, M. ); Gordon, A.Z. )

    1989-04-14

    The IGR emission control technology controls SO{sub 2}/NO{sub x}, and particulate emissions from coal combustion flue gases. The technology uses an electrochemical solid-state reactor which converts SO{sub 2} and NO{sub X} to S, N{sub 2}, and O{sub 2}. The cell electrolyte is a solid electrolyte, namely a high surface area ceramic oxide-ion conductor. Three tasks were active during this quarter: Task (1), Procurement, Construction and Debugging of the Electrochemical Reactors and Particulate Removal System, Tasks, (2) Reactor Operation on SO{sub 2}/NO{sub X} Spiked Gas Streams, and Task (3) Electrocatalysts Preparation and Screening Studies. In Task (1) the particulate control apparatus has been completely installed and its operation is being examined with respect to filtration materials and solid electrolyte. In Task (2) electrochemical measurements were made with oxide ion conducting ceramic disks in gases containing NO and SO{sub 2}. In Task (3) the electrochemical measurements are being made using a series of electrocatalysts in gases containing NO, SO{sub 2}, and oxygen. 9 figs., 1 tab.

  16. 40 CFR 60.1775 - What types of stack tests must I conduct?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-Stack Testing § 60.1775 What types of stack tests must I conduct? Conduct initial and annual stack tests to measure the emission levels of dioxins/furans, cadmium, lead, mercury, particulate matter,...

  17. 40 CFR 60.1775 - What types of stack tests must I conduct?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-Stack Testing § 60.1775 What types of stack tests must I conduct? Conduct initial and annual stack tests to measure the emission levels of dioxins/furans, cadmium, lead, mercury, particulate matter,...

  18. 40 CFR 60.1775 - What types of stack tests must I conduct?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-Stack Testing § 60.1775 What types of stack tests must I conduct? Conduct initial and annual stack tests to measure the emission levels of dioxins/furans, cadmium, lead, mercury, particulate matter,...

  19. 40 CFR 62.15235 - How are the stack test data used?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., 1999 Stack Testing § 62.15235 How are the stack test data used? You must use results of stack tests for dioxins/furans, cadmium, lead, mercury, particulate matter, opacity, hydrogen chloride, and fugitive...

  20. Statistical analysis of particulate concentration from electrode erosion of gas discharge

    NASA Astrophysics Data System (ADS)

    Zhong, Wei; Liu, Yunlong; Wang, Lei; Jin, Dazhi; Tan, Xiaohua

    2017-01-01

    In discharge processes, electrode erosion is inevitable and may be a primary cause of gap failure. Features generated from electrode erosion, such as particulates and pits, would lead to field distortion and self-breakdown failure, in essence. To quantitatively clarify how these features of erosion are generated as the discharge shot accumulates, this paper introduces a statistical method to analyze particulate concentration in the eroded surface. Based on experimental data from laser confocal microscopy, this method could extract and process the profile of the electrode surface after different discharge shots. Statistical results indicate that conditioning effects have been found in the first 100 shots, where the discharge arc plays a role to polish more prominently, rather than ablate, the electrode surface. After this period, electrode erosion could be found to be increasingly heavier and the number of particulates and pits increases rapidly. The proportion function of the particulates height or pits depth can be fitted by power distribution and the correlations between the two function coefficients a, b and discharge shots number n are roughly linear, positive and negative, respectively.

  1. Emission and distribution of PCDD/Fs, chlorobenzenes, chlorophenols, and PAHs from stack gas of a fluidized bed and a stoker waste incinerator in China.

    PubMed

    Wang, Tianjiao; Chen, Tong; Lin, Xiaoqing; Zhan, Mingxiu; Li, Xiaodong

    2016-12-29

    The concentrations, homologue, and congener profiles, as well as the gas/particle distribution of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), chlorobenzenes (CBzs), chlorophenols (CPhs), and polyaromatic hydrocarbons (PAHs) from stack gas of two different municipal solid waste incinerators in China, were characterized. The incinerators were a stoker furnace incinerator equipped with the advanced air pollution control device (APCD) and a common circulating fluidized bed (CFB) furnace. The concentration of PCDD/Fs in the stack gas of the stoker incinerator ranged 0.011-0.109 ng international toxic equivalent factor (I-TEQ)/Nm(3) and was below the current limit for PCDD/F emissions from the municipal solid waste incinerators (MSWIs) in China (0.1 ng I-TEQ/Nm(3)) in most of the cases. Moreover, the concentration of PCDD/Fs in the stack gas of the stoker incinerator was significantly lower than that of the CFB incinerator (0.734 to 24.6 ng I-TEQ/Nm(3)). In both incinerators, the majority of the total PCDD/F emissions (above 90%) ended up in the gas phase. 2,3,4,7,8-PeCDF, which occupied 24.3-43.6 and 32.5-75.6% of I-TEQ contribution in MSWIs A and B, respectively, was the most abundant congener. However, different types of incinerators and APCDs induced different congener and homologue distributions. The total concentration of CBzs from the stoker incinerator (0.05-3.2 μg/Nm(3)) was also much lower than that formed from the CFB incinerator (10.9-75.2 μg/Nm(3)). The phase distribution of CBzs followed the same pattern as with the PCDD/Fs. Moreover, the emission level of CBz was 100-1000 times higher than that of the PCDD/Fs, which determines the applicability of CBzs as indicators of PCDD/F emissions. High correlations between the emission concentrations of PCDD/Fs, TeCBz, and PCBz in specific ranges were revealed. Furthermore, high concentrations of CPhs (0.6-141.0 μg/Nm(3)) and PAHs (148.6-4986.5 μg/Nm(3)) were detected in the stack gases of MSWI

  2. Carboxylic acids in gas and PM2.5 particulate phase at a rural mountain site in northeastern United States

    NASA Astrophysics Data System (ADS)

    Hussain, M. M.; Khan, A. R.; Khwaja, H. A.

    2009-12-01

    Low molecular weight carboxylic acids are important constituents of the organic fraction of atmospheric particulate matter in rural and polluted regions. The knowledge on their source is sparse, however, and organic aerosols in general need to better characterized. Atmospheric gas- and particle-phase carboxylic acids (formic, acetic, pyruvic, glyoxalic, benzoaic, adipic, succinic, malonic, and oxalic) and related compounds were measured during August 2002 at a rural site, Whiteface Mountain, NY. Formic and acetic acids were present in the PM2.5 fraction and in the gas phase. Other seven carboxylic acids were below the detection limit in all samples. Formic and acetic acid were present in the atmosphere mostly in the gaseous form with less than 10% in the PM2.5 fraction. Concentrations of formic acid and acetic acid were in the 0.5 - 2.4 ppbv and 0.6 - 1.9 ppbv ranges, respectively. Formic-to-acetic acid ratios less than one (0.88) were recorded, likely due to an increase in acetic acid contribution from direct emissions. In the fine particulate mode (PM2.5 ) the concentrations for acetic acid and formic acid were 120 - 400 and 10 - 180 ng/m3 , respectively. Backward trajectory data indicate that air mass originated at midwestern region on August 5th and gradually moved towards north on August 9th. Correlation of formic acid with sulfate was investigated to interpret their possible secondary formation pathways. A strong correlation (0.73) was observed between formic acid and sulfate in PM2.5 particulates. Since the source of sulfate found at Whiteface Mountain widely accepted as anthropogenic, its association with formic acid indicated that the later might have anthropogenic source.

  3. Simultaneous SO[sub 2]/NO/particulate removal from coal combustion gas by solid-state electrochemical technology

    SciTech Connect

    Cornell, L.P.; Cook, W.J.; Keyvani, M.; Neyman, M. ); Helfritch, D.J. . Environmental Services and Technologies Div.)

    1991-01-21

    A solid-state electrochemical process now in an early stage of development converts NO[sub x]and SO[sub x] to nitrogen, oxygen, and sulfur. Process objectives are to remove 90+% of SO[sub x] and NO[sub x] and 99% of particulates from Ohio coal combustion flue gases. The electrochemical reactor cell uses ionically conductive ceramics as electrolyte, and electronically conductive materials (including some ceramics) as electrodes; there are no moving parts, no consumable reagents, no by-product sludges, and no process fluids except the flue gas. Downstream of the electro-chemical cell, particulates are removed with a filter or electrostatic precipitator and elemental sulfur is condensed. This work developed and tested electrocatalysts for their ability to selectively reduce SO[sub 2] and NO[sub x] in the presence of oxygen gas in concentrations typical of coal combustion flue gases. Several solid electrolytes and various electrode materials were also tested for use in the electrochemical cell. Gold was chosen as the electrode in the tests because it is porous, resistant to chemical attack, and conductive. Electrocatalyst coatings containing a single transition metal were applied to one inch diameter yttria stabilized ceria disks and tested for NO and SO[sub 2] reduction.

  4. Exhaust-stack nozzle area and shape for individual cylinder exhaust-gas jet-propulsion system

    NASA Technical Reports Server (NTRS)

    Pinkel, Benjamin; Turner, Richard; Voss, Fred; Humble, Leroy V

    1943-01-01

    This report presents the results of an investigation conducted on the effect of exhaust-stack nozzle area, shape, and length on engine power, jet thrust, and gain in net thrust (engine propeller plus jet). Single-cylinder engine data were obtained using three straight stacks 25, 44, and 108 inches in length; an S-shaped stack, a 90 degree bend, a 180 degree bend, and a short straight stack having a closed branch faired into it. Each stack was fitted with nozzles varying in exit area from 0.91 square inch to the unrestricted area of the stack of 4.20 square inches. The engine was generally operated over a range of engine speeds from 1300 to 2100 r.p.m, inlet-manifold pressures from 22 to 30 inches of mercury absolute, and a fuel-air ratio of 0.08. The loss in engine power, the jet thrust, and the gain in net thrust are correlated in terms of several simple parameters. An example is given for determining the optimum nozzle area and the overall net thrust.

  5. PM2.5 and ultrafine particulate matter emissions from natural gas-fired turbine for power generation

    NASA Astrophysics Data System (ADS)

    Brewer, Eli; Li, Yang; Finken, Bob; Quartucy, Greg; Muzio, Lawrence; Baez, Al; Garibay, Mike; Jung, Heejung S.

    2016-04-01

    The generation of electricity from natural gas-fired turbines has increased more than 200% since 2003. In 2007 the South Coast Air Quality Management District (SCAQMD) funded a project to identify control strategies and technologies for PM2.5 and ultrafine emissions from natural gas-fired turbine power plants and test at pilot scale advanced PM2.5 technologies to reduce emissions from these gas turbine-based power plants. This prompted a study of the exhaust from new facilities to better understand air pollution in California. To characterize the emissions from new natural gas turbines, a series of tests were performed on a GE LMS100 gas turbine located at the Walnut Creek Energy Park in August 2013. These tests included particulate matter less than 2.5 μm in diameter (PM2.5) and wet chemical tests for SO2/SO3 and NH3, as well as ultrafine (less than 100 nm in diameter) particulate matter measurements. After turbine exhaust was diluted sevenfold with filtered air, particle concentrations in the 10-300 nm size range were approximately two orders of magnitude higher than those in the ambient air and those in the 2-3 nm size range were up to four orders of magnitude higher. This study also found that ammonia emissions were higher than expected, but in compliance with permit conditions. This was possibly due to an ammonia imbalance entering the catalyst, some flue gas bypassing the catalyst, or not enough catalyst volume. SO3 accounted for an average of 23% of the total sulfur oxides emissions measured. While some of the SO3 is formed in the combustion process, it is likely that the majority formed as the SO2 in the combustion products passed across the oxidizing CO catalyst and SCR catalyst. The 100 MW turbine sampled in this study emitted particle loadings of 3.63E-04 lb/MMBtu based on Methods 5.1/201A and 1.07E-04 lb/MMBtu based on SMPS method, which are similar to those previously measured from turbines in the SCAQMD area (FERCo et al., 2014), however, the turbine

  6. Simultaneous particulates, NO sub x , SO sub x removal from flue gas by all solid-state electrochemical technology

    SciTech Connect

    Cook, W.J.; Cornell, L.P.; Keyvani, M.; Neyman, M. ); Helfritch, D.J. . Environmental Services and Technologies Div.)

    1990-04-17

    The process control SO{sub x}, NO{sub x}, and particulate emission from coal combustion flue gases. It is based on a solid-state, electrochemical reactor which converts NO{sub x} and SO{sub 2} to nitrogen, sulfur, and oxygen. Sulfur is condensed downstream at a lower temperature. Particulates are removed with a filter or electrostatic precipitator. The process utilizes no other material input (flue gas is the only fluid), has no moving parts, and produces no sludge(s). The reactor consists of an electrochemical cell where the electrolyte is a solid oxygen ion conducting ceramic such as stabilized ceria or zirconia and the electrodes are electronically conductive material(s). Porous metal such as silver or gold were used as electrodes in the experimental work. Acceptable reduction rates and electric power requirements for sulfur dioxide and nitrogen oxide removal were obtained in up to 1% oxygen with ruthenium and strontium ruthenate electrocatalysts. Electrocatalytic improvements are needed for higher oxygen concentrations, with the NO reduction rates and efficiencies being most sensitive to oxygen concentration. The best electrocatalysts were ruthenium and the perovskite strontium ruthenate. 37 refs., 23 figs., 26 tabs.

  7. Limestone/adipic acid FGD and stack opacity reduction pilot plant tests at Big Rivers

    SciTech Connect

    Laslo, D.; Bakke, E.; Chisholm, E.

    1984-01-01

    Big Rivers Electric Corporation (BREC) contracted Peabody Process Systems, Inc. (PPSI) to install a flue gas cleaning (FGC) pilot plant at the BREC R.D. Green Station Unit No. 2 located at Sebree, KY. A six month test program was completed demonstrating technology for: alternatives to using lime as an alkali; methods for improving cake dewatering; identification of the causes of high stack opacity; and methods for the reduction of high stack opacity. This paper presents highlights extracted from the reports submitted by PPSI to BREC on this test program. BREC was primarily interested in reduction of operating costs, if possible, by using an alkali less expensive than lime, and by improving the poor dewatering characteristic inherent in a dolomitic lime system. BREC was also within compliance for particulate emissions and opacity in the duct after the dry electrostatic precipitator, but not in compliance with the stack opacity regulation, and therefore wanted to investigate methods for stack opacity reduction.

  8. Pyrolysis-gas chromatography/mass spectrometry analyses of biological particulates collected during recent space shuttle missions

    NASA Technical Reports Server (NTRS)

    Matney, M. L.; Limero, T. F.; James, J. T.

    1994-01-01

    Biological particulates collected on air filters during shuttle missions (STS-40 and STS-42) were identified using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). A method was developed for identifying the atmospheric particles and their sources through the analysis of standard materials and the selection of "marker" compounds specific to the particle type. Pyrolysis spectra of biological standards were compared with those of airborne particles collected during two space shuttle missions; marker compounds present in the shuttle particle spectra were matched with those of the standards to identify the source of particles. Particles of 0,5--1-mm diameter and weighing as little as 40 micrograms could be identified using this technique. The Py-GC/MS method identified rat food and soilless plant-growth media as two sources of particles collected from the shuttle atmosphere during flight.

  9. Simultaneous particulates, NO sub x , SO sub x removal from flue gas by all solid-state electrochemical technology

    SciTech Connect

    Cook, W.J.; Cornell, L.P.; Keyvani, M.; Neyman, M.

    1989-11-09

    The objective is to develop an all solid-state electrochemical technology to control SOx, NOx, and particulate emissions from coal combustion flue gases. It is based on a solid-state, electrochemical reactor which reduces NOx and SO{sub 2} to nitrogen, sulfur, and oxygen. Work was performed in the area of electrocatalyst preparation and testing. Transition metal oxides (Ru, Cr, V, W, Co, Mo), mixtures of transition metal oxides and transition metal oxide perovskites were tested as electrocatalysts. The electrocatalyst along with gold electrodes were coated and fired on a yittria stabilized ceria solid electrolyte disk. The reduction of NO and SO{sub 2} in gas mixtures containing 0 to 4% oxygen was measured while a voltage was applied to the disk. 3 refs., 5 figs., 4 tabs.

  10. Simultaneous particulates NO sub x , SO sub x removal from flue gas by all solid-state electrochemical technology

    SciTech Connect

    Cook, W.J.; Hossain, M.S.; Neyman, M. ); Gordon, A.Z. )

    1988-03-17

    The IGR emission control technology controls SOx, NOx, and particulate emissions from coal combustion flue gases. It is based on a solid-state, flow-through, electrochemical reactor which reduces NOx and SO{sub 2} to nitrogen, sulfur, and oxygen. The cell electrolyte is a solid electrolyte, normally a high surface area ceramic oxide-ion conductor. Two tasks were active during this quarter, Task (1) Development of 10 Cubic Feet/Min High Surface Area Electrochemical Reactors and Task (2) Electrocatalyst Preparation and Screening Studies. Task (2) is the screening of electrocatalysts for high oxygen overpotential and low SO{sub 2} and NO{sub x} overpotential. Electrochemical measurements were made with oxide ion conducting ceramic disks in nitric oxide and sulfur dioxide gas mixtures. 1 ref., 9 figs.

  11. Sampling of power plant stacks for air toxic emissions: Final report for Phases 1 and 2

    SciTech Connect

    1995-04-28

    A test program to collect and analyze size-fractionated stack gas particulate samples for selected inorganic hazardous air pollutants (HAPs) was conducted . Specific goals of the program are (1) the collection of one-gram quantities of size-fractionated stack gas particulate matter for bulk (total) and surface chemical characterization, and (2) the determination of the relationship between particle size, bulk and surface (leachable) composition, and unit load. The information obtained from this program identifies the effects of unit load, particle size, and wet FGD system operation on the relative toxicological effects of exposure to particulate emissions. Field testing was conducted in two phases. The Phase I field program was performed over the period of August 24 through September 20, 1992, at the Tennessee Valley Authority Widows Creek Unit 8 Power Station, located near Stevenson (Jackson County), Alabama, on the Tennessee River. Sampling activities for Phase II were conducted from September 11 through October 14, 1993. Widows Creek Unit 8 is a 575-megawatt plant that uses bituminous coal averaging 3.7% sulfur and 13% ash. Downstream of the boiler, a venture wet scrubbing system is used for control of both sulfur dioxide and particulate emissions. There is no electrostatic precipitator (ESP) in this system. This system is atypical and represents only about 5% of the US utility industry. However, this site was chosen for this study because of the lack of information available for this particulate emission control system.

  12. Interim Particulate Matter Test Method for the Determination of Particulate Matter from Gas Turbine Engines, SERDP Project WP-1538 Final Report

    EPA Science Inventory

    Under Project No. WP-1538 of the Strategic Environmental Research and Development Program, the U. S. Air Force's Arnold Engineering Development Center (AEDC) is developing an interim test method for non-volatile particulate matter (PM) specifically for the Joint Strike Fighter (J...

  13. Impact of natural gas development in the Marcellus and Utica shales on regional ozone and fine particulate matter levels

    NASA Astrophysics Data System (ADS)

    Roohani, Yusuf H.; Roy, Anirban A.; Heo, Jinhyok; Robinson, Allen L.; Adams, Peter J.

    2017-04-01

    The Marcellus and Utica shale formations have recently been the focus of intense natural gas development and production, increasing regional air pollutant emissions. Here we examine the effects of these emissions on regional ozone and fine particulate matter (PM2.5) levels using the chemical transport model, CAMx, and estimate the public health costs with BenMAP. Simulations were performed for three emissions scenarios for the year 2020 that span a range potential development storylines. In areas with the most gas development, the 'Medium Emissions' scenario, which corresponds to an intermediate level of development and widespread adoption of new equipment with lower emissions, is predicted to increase 8-hourly ozone design values by up to 2.5 ppbv and average annual PM2.5 concentrations by as much as 0.27 μg/m3. These impacts could range from as much as a factor of two higher to a factor of three lower depending on the level of development and the adoption of emission controls. Smaller impacts (e.g. 0.1-0.5 ppbv of ozone, depending on the emissions scenario) are predicted for non-attainment areas located downwind of the Marcellus region such as New York City, Philadelphia and Washington, DC. Premature deaths for the 'Medium Emissions' scenario are predicted to increase by 200-460 annually. The health impacts as well as the changes in ozone and PM2.5 were all driven primarily by NOx emissions.

  14. Particulate and gas-phase products from the atmospheric degradation of chlorpyrifos and chlorpyrifos-oxon

    NASA Astrophysics Data System (ADS)

    Borrás, Esther; Ródenas, Milagros; Vázquez, Mónica; Vera, Teresa; Muñoz, Amalia

    2015-12-01

    The phosphorothioate structure is highly present in several pesticides. However, there is a lack of information about its degradation process in air and the secondary pollutants formed. Herein, the atmospheric reactions of chlorpyrifos, one of the most world-used insecticide, and its main degradation product - chlorpyrifos-oxon - are described. The photo-oxidation under the presence of NOx was studied in a large outdoor simulation chamber for both chlorpyrifos and chlorpyrifos-oxon, observing a rapid degradation (Half lifetime < 3.5 h for both compounds). Also, the photolysis reactions of both were studied. The formation of particulate matter (aerosol mass yield ranged 6-59%) and gaseous products were monitored. The chemical composition of minor products was studied, identifying 15 multi-oxygenated derivatives. The most abundant products were ring-retaining molecules such as 3,5,6-trichloropyridin-2-ol and ethyl 3,5,6-trichloropyridin-2-yl hydrogen phosphate. An atmospheric degradation mechanism has been amplified based on an oxidation started with OH-nucleophilic attack to Pdbnd S bond.

  15. Evaluation of methods for measuring particulate matter emissions from gas turbines.

    PubMed

    Petzold, Andreas; Marsh, Richard; Johnson, Mark; Miller, Michael; Sevcenco, Yura; Delhaye, David; Ibrahim, Amir; Williams, Paul; Bauer, Heidi; Crayford, Andrew; Bachalo, William D; Raper, David

    2011-04-15

    The project SAMPLE evaluated methods for measuring particle properties in the exhaust of aircraft engines with respect to the development of standardized operation procedures for particulate matter measurement in aviation industry. Filter-based off-line mass methods included gravimetry and chemical analysis of carbonaceous species by combustion methods. Online mass methods were based on light absorption measurement or used size distribution measurements obtained from an electrical mobility analyzer approach. Number concentrations were determined using different condensation particle counters (CPC). Total mass from filter-based methods balanced gravimetric mass within 8% error. Carbonaceous matter accounted for 70% of gravimetric mass while the remaining 30% were attributed to hydrated sulfate and noncarbonaceous organic matter fractions. Online methods were closely correlated over the entire range of emission levels studied in the tests. Elemental carbon from combustion methods and black carbon from optical methods deviated by maximum 5% with respect to mass for low to medium emission levels, whereas for high emission levels a systematic deviation between online methods and filter based methods was found which is attributed to sampling effects. CPC based instruments proved highly reproducible for number concentration measurements with a maximum interinstrument standard deviation of 7.5%.

  16. CRADA opportunities in removal of particulates from hot-gas streams by filtration

    SciTech Connect

    Smith, D H

    1995-06-01

    Our analyses of samples and operating data from the Pressurized Fluidized Bed Combustion (PFBC), cyclone, and filtration units of the Tidd Clean Coal demonstration facility show that calcined dolomitic sorbent reacted with SO{sub 2} (and O{sub 2}) to form Sulfates (CaSO{sub 4} and CaMgn [SO{sub 4}]n+1) not only in the PFBC bed, but also in the filtration vessel. Analyses of limited data from the journal literature suggest that the filter-vessel reactions may have produced sulfate {open_quotes}necks,{close_quotes} which bonded the particles together, thus substantially increasing the critical angle of repose and shear tensile strengths of the filtered powders. This proposed mechanism rationalizes the {open_quotes}bridging{close_quotes} and other particle-accumulation problems that caused filter breakage. Engineering services potentially available to resolve these problems include elucidation and modeling of ex-situ and in-situ filter-vessel chemistry, measurement and modeling of particulate materials properties, and measurement and modeling of cleaning back-pulse aerodynamics and cleaning efficiencies.

  17. Water tank experiment of gas diffusion from a stack in stably and unstably stratified layers under calm conditions

    NASA Astrophysics Data System (ADS)

    Ohba, R.; Kakishima, S.; Ito, S.

    Water tank experiments were conducted to investigate plume rrise and diffusion of gases discharged from a stack under calm conditions with stable and unstable thermal stratifications. First, tracer liquid with fluorescent dye and salt was emitted from a model of a stack in a stably stratified layer and the behavior of a plume was recorded by video camera. Using these results. we obtained formulae for plume rise height, and horizontal and vertical width of a plume as a function of thedensimetric Froude number, stability ratio and time. After the completion of these experiments under stable conditions, an unstably stratified layer was developed from a ground surface by heating a floor and the resulting concentration distribution was measured with electric conductivity probes. Using these results, we analyzed the height of the convection layer and concentration distribution as a function of the overall Richardson number and time.

  18. Particulate Scrubbing Performance of the High Level Caves Off-Gas System

    SciTech Connect

    Wright, G.T.

    2001-08-16

    Performance tests were conducted at the ETF using off-gas from the Small Cylindrical Melter (SCM) -2. The purpose of these tests was to develop data for comparing small and full scale equipment performance. This reports discusses those test results.

  19. Tailor Made Synthesis of T-Shaped and π-STACKED Dimers in the Gas Phase: Concept for Efficient Drug Design and Material Synthesis

    NASA Astrophysics Data System (ADS)

    Kumar, Sumit; Das, Aloke

    2013-06-01

    Non-covalent interactions play a key role in governing the specific functional structures of biomolecules as well as materials. Thus molecular level understanding of these intermolecular interactions can help in efficient drug design and material synthesis. It has been found from X-ray crystallography that pure hydrocarbon solids (i.e. benzene, hexaflurobenzene) have mostly slanted T-shaped (herringbone) packing arrangement whereas mixed solid hydrocarbon crystals (i.e. solid formed from mixtures of benzene and hexafluorobenzene) exhibit preferentially parallel displaced (PD) π-stacked arrangement. Gas phase spectroscopy of the dimeric complexes of the building blocks of solid pure benzene and mixed benzene-hexafluorobenzene adducts exhibit similar structural motifs observed in the corresponding crystal strcutures. In this talk, I will discuss about the jet-cooled dimeric complexes of indole with hexafluorobenzene and p-xylene in the gas phase using Resonant two photon ionzation and IR-UV double resonance spectroscopy combined with quantum chemistry calculations. In stead of studying benzene...p-xylene and benzene...hexafluorobenzene dimers, we have studied corresponding indole complexes because N-H group is much more sensitive IR probe compared to C-H group. We have observed that indole...hexafluorobenzene dimer has parallel displaced (PD) π-stacked structure whereas indole...p-xylene has slanted T-shaped structure. We have shown here selective switching of dimeric structure from T-shaped to π-stacked by changing the substituent from electron donating (-CH3) to electron withdrawing group (fluorine) in one of the complexing partners. Thus, our results demonstrate that efficient engineering of the non-covalent interactions can lead to efficient drug design and material synthesis.

  20. EPRI wet stacks design guide

    SciTech Connect

    Weilert, C.V.; Pattison, D.C.; Richart, S.D.

    1995-06-01

    Because of the high cost of reheat, wet stacks are being considered for new or retrofit applications of wet FGD systems in the United States. All retrofit systems designed for compliance with Phase I of the Acid Rain Control program under the Clean Air Act have utilized wet stacks. For Phase II, utilities with existing wet FGD systems would benefit from overscrubbing. For those units which currently use bypass reheat, this could be accomplished by closing the bypass to treat the entire boiler flue gas stream. This would require conversion to wet stack operation. Due to the level of interest in these wet stack scenarios for future FGD applications, EPRI, in a tailored collaboration with NYSEG, retained Bums & McDonnell and DynaFlow Systems to prepare a design guide for wet stacks. This paper provides a brief summary of the wet stacks design guide.

  1. Potential health hazards from thermal degradation events - Particulate vs. gas phase effects

    NASA Technical Reports Server (NTRS)

    Oberdorster, Gunter; Ferin, Juraj; Finkelstein, Jacob; Baggs, Raymond; Stavert, D. M.; Lehnert, Bruce E.

    1992-01-01

    The effect of instillation of ultrafine TiO2 particles (10-nm anatase-TiO2 and 12-nm rutile-TiO2 (administered in doses from 60 to 1000 microg/rat and 500 microg/rat, respectively) on the respiratory tract of exposed rats was compared to the effects of larger (250 nm anatase-TiO2 and 220-nm rutile-TiO2 particles (given in doses 500 or 1000 microg/rat and 500 microg/rat, respectively). These effects were also compared to the effects of inhalation of 20-nm and 250-nm anatase-TiO2 particles and inhalation with surrogate gas phase components (HF and HCl). It was found that ultrafine TiO2 particles induced greater inflammatory reaction in the lung, had greater adverse effect on alveolar macrophage-mediated clearance function, and had a greater potential to induce mediators which can adversely affect other lung cells than did larger-sized particles. Inhalation of surrogate gas phase components caused injury only to the upper respiratory tract, in contrast to the ultrafine particles, which affected the deep lung.

  2. The Direct FuelCell™ stack engineering

    NASA Astrophysics Data System (ADS)

    Doyon, J.; Farooque, M.; Maru, H.

    FuelCell Energy (FCE) has developed power plants in the size range of 300 kW to 3 MW for distributed power generation. Field-testing of the sub-megawatt plants is underway. The FCE power plants are based on its Direct FuelCell™ (DFC) technology. This is so named because of its ability to generate electricity directly from a hydrocarbon fuel, such as natural gas, by reforming it inside the fuel cell stack itself. All FCE products use identical 8000 cm 2 cell design, approximately 350-400 cells per stack, external gas manifolds, and similar stack compression systems. The difference lies in the packaging of the stacks inside the stack module. The sub-megawatt system stack module contains a single horizontal stack whereas the MW-class stack module houses four identical vertical stacks. The commonality of the design, internal reforming features, and atmospheric operation simplify the system design, reduce cost, improve efficiency, increase reliability and maintainability. The product building-block stack design has been advanced through three full-size stack operations at company's headquarters in Danbury, CT. The initial proof-of-concept of the full-size stack design was verified in 1999, followed by a 1.5 year of endurance verification in 2000-2001, and currently a value-engineered stack version is in operation. This paper discusses the design features, important engineering solutions implemented, and test results of FCE's full-size DFC stacks.

  3. Effects of Fuel Aromatic Content on Nonvolatile Particulate Emissions of an In-Production Aircraft Gas Turbine.

    PubMed

    Brem, Benjamin T; Durdina, Lukas; Siegerist, Frithjof; Beyerle, Peter; Bruderer, Kevin; Rindlisbacher, Theo; Rocci-Denis, Sara; Andac, M Gurhan; Zelina, Joseph; Penanhoat, Olivier; Wang, Jing

    2015-11-17

    Aircraft engines emit particulate matter (PM) that affects the air quality in the vicinity of airports and contributes to climate change. Nonvolatile PM (nvPM) emissions from aircraft turbine engines depend on fuel aromatic content, which varies globally by several percent. It is uncertain how this variability will affect future nvPM emission regulations and emission inventories. Here, we present black carbon (BC) mass and nvPM number emission indices (EIs) as a function of fuel aromatic content and thrust for an in-production aircraft gas turbine engine. The aromatics content was varied from 17.8% (v/v) in the neat fuel (Jet A-1) to up to 23.6% (v/v) by injecting two aromatic solvents into the engine fuel supply line. Fuel normalized BC mass and nvPM number EIs increased by up to 60% with increasing fuel aromatics content and decreasing engine thrust. The EIs also increased when fuel naphthalenes were changed from 0.78% (v/v) to 1.18% (v/v) while keeping the total aromatics constant. The EIs correlated best with fuel hydrogen mass content, leading to a simple model that could be used for correcting fuel effects in emission inventories and in future aircraft engine nvPM emission standards.

  4. Gas Turbine Engine Nonvolatile Particulate Matter Mass Emissions: Correlation with Smoke Number for Conventional and Alternative Fuel Blends.

    PubMed

    Christie, Simon; Lobo, Prem; Lee, David; Raper, David

    2017-01-17

    This study evaluates the relationship between the emissions parameters of smoke number (SN) and mass concentration of nonvolatile particulate matter (nvPM) in the exhaust of a gas turbine engine for a conventional Jet A-1 and a number of alternative fuel blends. The data demonstrate the significant impact of fuel composition on the emissions and highlight the magnitude of the fuel-induced uncertainty for both SN within the Emissions Data Bank as well as nvPM mass within the new regulatory standard under development. Notwithstanding these substantial differences, the data show that correlation between SN and nvPM mass concentration still adheres to the first order approximation (FOA3), and this agreement is maintained over a wide range of fuel compositions. Hence, the data support the supposition that the FOA3 is applicable to engines burning both conventional and alternative fuel blends without adaptation or modification. The chemical composition of the fuel is shown to impact mass and number concentration as well as geometric mean diameter of the emitted nvPM; however, the data do not support assertions that the emissions of black carbon with small mean diameter will result in significant deviations from FOA3.

  5. Application of multicriteria decision making methods to compression ignition engine efficiency and gaseous, particulate, and greenhouse gas emissions.

    PubMed

    Surawski, Nicholas C; Miljevic, Branka; Bodisco, Timothy A; Brown, Richard J; Ristovski, Zoran D; Ayoko, Godwin A

    2013-02-19

    Compression ignition (CI) engine design is subject to many constraints, which present a multicriteria optimization problem that the engine researcher must solve. In particular, the modern CI engine must not only be efficient but must also deliver low gaseous, particulate, and life cycle greenhouse gas emissions so that its impact on urban air quality, human health, and global warming is minimized. Consequently, this study undertakes a multicriteria analysis, which seeks to identify alternative fuels, injection technologies, and combustion strategies that could potentially satisfy these CI engine design constraints. Three data sets are analyzed with the Preference Ranking Organization Method for Enrichment Evaluations and Geometrical Analysis for Interactive Aid (PROMETHEE-GAIA) algorithm to explore the impact of (1) an ethanol fumigation system, (2) alternative fuels (20% biodiesel and synthetic diesel) and alternative injection technologies (mechanical direct injection and common rail injection), and (3) various biodiesel fuels made from 3 feedstocks (i.e., soy, tallow, and canola) tested at several blend percentages (20-100%) on the resulting emissions and efficiency profile of the various test engines. The results show that moderate ethanol substitutions (~20% by energy) at moderate load, high percentage soy blends (60-100%), and alternative fuels (biodiesel and synthetic diesel) provide an efficiency and emissions profile that yields the most "preferred" solutions to this multicriteria engine design problem. Further research is, however, required to reduce reactive oxygen species (ROS) emissions with alternative fuels and to deliver technologies that do not significantly reduce the median diameter of particle emissions.

  6. Comparative study for hardwood and softwood forest biomass: chemical characterization, combustion phases and gas and particulate matter emissions.

    PubMed

    Amaral, Simone Simões; de Carvalho, João Andrade; Costa, Maria Angélica Martins; Soares Neto, Turíbio Gomes; Dellani, Rafael; Leite, Luiz Henrique Scavacini

    2014-07-01

    Two different types of typical Brazilian forest biomass were burned in the laboratory in order to compare their combustion characteristics and pollutant emissions. Approximately 2 kg of Amazon biomass (hardwood) and 2 kg of Araucaria biomass (softwood) were burned. Gaseous emissions of CO2, CO, and NOx and particulate matter smaller than 2.5 μm (PM2.5) were evaluated in the flaming and smoldering combustion phases. Temperature, burn rate, modified combustion efficiency, emissions factor, and particle diameter and concentration were studied. A continuous analyzer was used to quantify gas concentrations. A DataRam4 and a Cascade Impactor were used to sample PM2.5. Araucaria biomass (softwood) had a lignin content of 34.9%, higher than the 23.3% of the Amazon biomass (hardwood). CO2 and CO emissions factors seem to be influenced by lignin content. Maximum concentrations of CO2, NOx and PM2.5 were observed in the flaming phase.

  7. Stacking Up

    ERIC Educational Resources Information Center

    Naylor, Jim

    2005-01-01

    Chimneys and stacks appear to be strong and indestructible, but chimneys begin to deteriorate from the moment they are built. Early on, no signs are apparent; but deterioration accelerates in subsequent years, and major repairs are soon needed instead of minor maintenance. With proper attention, most structures can be repaired and continue to…

  8. Field studies: Test method for on-line continuous measurement of total hydrocarbons (THC) and non-methane hydrocarbons (NMHC) in stack gas

    SciTech Connect

    Hsiao, H.H.; Lai, C.C.; Chu, H.W.; Cheng, H.

    1999-07-01

    A new method for on-line monitoring of total hydrocarbons and non-methane hydrocarbons in stack gas simultaneously was developed in this study. Based on the principle of on-line GC/FID, the method was developed and can be considered as a new modification of the Method 25 and 25A of US EPA. Major advantages of the method included (1) capability of distinguishing methane as Method 25; (2) near-real-time results; (3) broad species coverage; (4) monitoring methane in straightforward manner; (5) low operation and maintenance costs. In the proposed method, test samples were continuously pumped from detection sources and loaded with a two-loop sampling valve. The samples were then injected into two GC columns-empty and molecular sieve columns. The empty column was used for detection of THC, and the molecular sieve column was for methane. The detector in this GC was FID. NMHC concentration was obtained by subtracting methane from THC. The tests were carried out to measure the THC and methane in waste gas in various industries, including surface coating, semiconductor manufacturing, synthetic leather industries. Recovery rates of THC in the samples were between 86% to 114% for about 100 m of transfer line of samples. For the standard gas, the recovery rate was about 101%, 6.6 % of measurement precision, and 88%--114% of accuracy. The results showed the promising and reliable measurement of the test method for THC and methane in waste gas.

  9. 40 CFR 60.1285 - What types of stack tests must I conduct?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Modification or Reconstruction is Commenced After June 6, 2001 Stack Testing § 60.1285 What types of stack.../furans, cadmium, lead, mercury, particulate matter, opacity, hydrogen chloride, and fugitive ash....

  10. 40 CFR 60.1285 - What types of stack tests must I conduct?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Modification or Reconstruction is Commenced After June 6, 2001 Stack Testing § 60.1285 What types of stack.../furans, cadmium, lead, mercury, particulate matter, opacity, hydrogen chloride, and fugitive ash....

  11. 40 CFR 60.1285 - What types of stack tests must I conduct?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Modification or Reconstruction is Commenced After June 6, 2001 Stack Testing § 60.1285 What types of stack.../furans, cadmium, lead, mercury, particulate matter, opacity, hydrogen chloride, and fugitive ash....

  12. Characterization of polycyclic aromatic hydrocarbon emissions in the particulate and gas phase from smoldering mosquito coils containing various atomic hydrogen/carbon ratios.

    PubMed

    Yang, Tzu-Ting; Lin, Shaw-Tao; Lin, Tser-Sheng; Chung, Hua-Yi

    2015-02-15

    The polycyclic aromatic hydrocarbon emissions in particulate and gas phases generated from smoldering mosquito coils containing various atomic H/C ratios were examined. Five types of mosquito coils were burned in a test chamber with a total airflow rate of 8.0 L/min at a constant relative humidity and temperature. The concentrations of individual PAHs were determined using the GC/MS technique. Among the used mosquito coils, the atomic H/C ratio ranged from 1.23 to 1.57, yielding total mass, gaseous, and particulate PAH emission factors of 28.17-78.72 mg/g, 26,139.80-35,932.98 and 5735.22-13,431.51 ng/g, respectively. The various partitions of PAHs in the gaseous and particulate phases were in the ranges, 70.26-83.70% and 16.30-29.74% for the utilized mosquito coils. The carcinogenic potency of PAH emissions in the particulate phase (203.82-797.76 ng/g) was approximately 6.92-25.08 times higher than that of the gaseous phase (26.27-36.07 ng/g). Based on the analyses of PAH emissions, mosquito coils containing the lowest H/C ratio, a low oxygen level, and additional additives (i.e., CaCO3) are recommended for minimizing the production of total PAH emission factors and carcinogenic potency.

  13. Composition, toxicity, and mutagenicity of particulate and semivolatile emissions from heavy-duty compressed natural gas-powered vehicles.

    PubMed

    Seagrave, JeanClare; Gigliotti, Andrew; McDonald, Jacob D; Seilkop, Steven K; Whitney, Kevin A; Zielinska, Barbara; Mauderly, Joe L

    2005-09-01

    Particulate matter (PM) and vapor-phase semivolatile organic compounds (SVOC) were collected from three buses fueled by compressed natural gas. The bus engines included a well-functioning, conventional engine; a "high emitter" engine; and a new technology engine with an oxidation catalyst. Chemical analysis of the emissions showed differences among these samples, with the high emitter sample containing markers of engine oil constituents. PM + SVOC samples were also collected for mutagenicity and toxicity testing. Extraction efficiencies from the collection media were lower than for similarly collected samples from gasoline or diesel vehicles. Responses to the recovered samples were compared on the basis of exhaust volume, to incorporate the emission rates into the potency factors. Mutagenicity was assessed by Salmonella reverse mutation assay. Mutagenicity was greatest for the high emitter sample and lowest for the new technology sample. Metabolic activation reduced mutagenicity in strain TA100, but not TA98. Toxicity, including inflammation, cytotoxicity, and parenchymal changes, was assessed 24 h after intratracheal instillation into rat lungs. Lung responses were generally mild, with little difference between the responses to equivalent volumes of emissions from the normal emitter and the new technology, but greater responses for the high emitter. These emission sample potencies are further compared on the basis of recovered mass with previously reported samples from normal and high-emitter gasoline and diesel vehicles. While mutagenic potencies for the CNG emission samples were similar to the range observed in the gasoline and diesel emission samples, lung toxicity potency factors were generally lower than those for the gasoline and diesel samples.

  14. Development of thermal desorption gas chromatography/mass spectrometry as a rapid method for ambient particulate characterization

    NASA Astrophysics Data System (ADS)

    Sheya, Sue Anne N.

    A direct thermal desorption gas chromatography/mass spectrometry (TD GC/MS) method for air particulate matter (PM) analysis of volatile and semivolatile organic compounds was investigated. This technique uses a specially designed microdesorption GC inlet utilizing an inductively heated ferromagnetic foil with a Curie point temperature suitable for desorption, which can accommodate microgram amounts of material deposited on a thin strip of quartz fiber filter. Liquid or solid samples can be rapidly desorbed within 10 s at 315°C, followed by 30--40 min of chromatography time. The results obtained by this technique were found to be statistically equivalent to those obtained by the conventional solvent extraction gas chromatography/mass spectrometry (SX GC/MS) method for analysis of aromatic and n alkane standards, single source soot particles, and PM 10 filter samples. Correlations between injecting an extract, desorbing an extract, and desorbing particles averaged R = 0.94, with a three way correlation averaging R = 0.97. High volume sampling conducted at 12 spatially distributed sites located along the US/Mexican border of the El Paso/Juarez metroplex supplied 24h PM 10 filters for an investigation combining thermal desorption with a rapid online chemical derivatization procedure, and multivariate methods of source attribution using principal component and canonical correlation analysis of the resultant chemical markers. Four major combustion related PM emission sources were revealed at these sites: automotive, waste burning, biomass burning and meat cooking. A second investigation conducted in the same area used mediumvolume sampling to collect 2 h timeresolved PM 10 receptor samples for TD GC/MS analysis. Additionally, 2 h samples for inorganic analysis, multichannel particle size distribution measurements, and meteorological data were collected enabling generation of circadian PM multicharacterization profiles. Factor analysis based receptor modeling using

  15. The use of a housecleaning product in an indoor environment leading to oxygenated polar compounds and SOA formation: Gas and particulate phase chemical characterization

    NASA Astrophysics Data System (ADS)

    Rossignol, S.; Rio, C.; Ustache, A.; Fable, S.; Nicolle, J.; Même, A.; D'Anna, B.; Nicolas, M.; Leoz, E.; Chiappini, L.

    2013-08-01

    This work investigates Secondary Organic Aerosol (SOA) formed by limonene ozonolysis using a housecleaning product in indoor environment. This study combines simulation chamber ozonolysis experiments and field studies in an experimental house allowing different scenarios of housecleaning product use in real conditions. Chemical speciation has been performed using a new method based on simultaneous sampling of both gas and particulate phases on sorbent tubes and filters. This method allowed the identification and quantification of about 35 products in the gas and particulate phases. Among them, products known to be specific from limonene ozonolysis such as limononaldehyde, ketolimonene and ketolimonic acid have been detected. Some other compounds such as 2-methylbutanoic acid had never been detected in previous limonene ozonolysis studies. Some compounds like levulinic acid had already been detected but their formation remained unexplained. Potential reaction pathways are proposed in this study for these compounds. For each experiment, chemical data are coupled together with physical characterization of formed particles: mass and size and number distribution evolution which allowed the observation of new particles formation (about 87,000 particle cm-3). The chemical speciation associated to aerosol size distribution results confirmed that limonene emitted by the housecleaning product was responsible for SOA formation. To our knowledge, this work provides the most comprehensive analytical study of detected compounds in a single experiment for limonene ozonolysis in both gaseous and particulate phases in real indoor environment.

  16. SDSS IV MaNGA: Deep observations of extra-planar, diffuse ionized gas around late-type galaxies from stacked IFU spectra

    NASA Astrophysics Data System (ADS)

    Jones, A.; Kauffmann, G.; D'Souza, R.; Bizyaev, D.; Law, D.; Haffner, L.; Bahé, Y.; Andrews, B.; Bershady, M.; Brownstein, J.; Bundy, K.; Cherinka, B.; Diamond-Stanic, A.; Drory, N.; Riffel, R. A.; Sánchez, S. F.; Thomas, D.; Wake, D.; Yan, R.; Zhang, K.

    2017-03-01

    We have conducted a study of extra-planar diffuse ionized gas using the first year data from the MaNGA IFU survey. We have stacked spectra from 49 edge-on, late-type galaxies as a function of distance from the midplane of the galaxy. With this technique we can detect the bright emission lines Hα, Hβ, [O ii]λλ3726, 3729, [O iii]λ5007, [N ii]λλ6549, 6584, and [S ii]λλ6717, 6731 out to about 4 kpc above the midplane. With 16 galaxies we can extend this analysis out to about 9 kpc, i.e. a distance of 2Re, vertically from the midplane. In the halo, the surface brightnesses of the [O ii] and Hα emission lines are comparable, unlike in the disk where Hα dominates. When we split the sample by specific star-formation rate, concentration index, and stellar mass, each subsample's emission line surface brightness profiles and ratios differ, indicating that extra-planar gas properties can vary. The emission line surface brightnesses of the gas around high specific star-formation rate galaxies are higher at all distances, and the line ratios are closer to ratios characteristic of H ii regions compared with low specific star-formation rate galaxies. The less concentrated and lower stellar mass samples exhibit line ratios that are more like H ii regions at larger distances than their more concentrated and higher stellar mass counterparts. The largest difference between different subsamples occurs when the galaxies are split by stellar mass. We additionally infer that gas far from the midplane in more massive galaxies has the highest temperatures and steepest radial temperature gradients based on their [N ii]/Hα and [O ii]/Hα ratios between the disk and the halo. SDSS IV.

  17. Regenerative process and system for the simultaneous removal of particulates and the oxides of sulfur and nitrogen from a gas stream

    DOEpatents

    Cohen, Mitchell R.; Gal, Eli

    1993-01-01

    A process and system for simultaneously removing from a gaseous mixture, sulfur oxides by means of a solid sulfur oxide acceptor on a porous carrier, nitrogen oxides by means of ammonia gas and particulate matter by means of filtration and for the regeneration of loaded solid sulfur oxide acceptor. Finely-divided solid sulfur oxide acceptor is entrained in a gaseous mixture to deplete sulfur oxides from the gaseous mixture, the finely-divided solid sulfur oxide acceptor being dispersed on a porous carrier material having a particle size up to about 200 microns. In the process, the gaseous mixture is optionally pre-filtered to remove particulate matter and thereafter finely-divided solid sulfur oxide acceptor is injected into the gaseous The government of the United States of America has rights in this invention pursuant to Contract No. DE-AC21-88MC 23174 awarded by the U.S. Department of Energy.

  18. Regenerative process and system for the simultaneous removal of particulates and the oxides of sulfur and nitrogen from a gas stream

    DOEpatents

    Cohen, M.R.; Gal, E.

    1993-04-13

    A process and system are described for simultaneously removing from a gaseous mixture, sulfur oxides by means of a solid sulfur oxide acceptor on a porous carrier, nitrogen oxides by means of ammonia gas and particulate matter by means of filtration and for the regeneration of loaded solid sulfur oxide acceptor. Finely-divided solid sulfur oxide acceptor is entrained in a gaseous mixture to deplete sulfur oxides from the gaseous mixture, the finely-divided solid sulfur oxide acceptor being dispersed on a porous carrier material having a particle size up to about 200 microns. In the process, the gaseous mixture is optionally pre-filtered to remove particulate matter and thereafter finely-divided solid sulfur oxide acceptor is injected into the gaseous mixture.

  19. 40 CFR 60.382 - Standard for particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for particulate matter. 60.382... Processing Plants § 60.382 Standard for particulate matter. (a) On and after the date on which the... stack emissions that: (1) Contain particulate matter in excess of 0.05 grams per dry standard...

  20. A potential instrumental counterpart to Method 5 for the continuous measurement of particulate matter emissions from combustion and other sources using isokinetic sample extraction technology followed by beta ray attenuation mass measurements

    SciTech Connect

    Griguoli, F.T.

    1997-12-31

    For many years opacity and other values available from optical devices have been used in an attempt to assess and often quantify particulate matter emissions from stationary sources, particularly combustion sources using coal. These opacity values have also been used to obtain mass concentration data. Today`s reality is such that pollution abatement technologies have become better and better, dry or wet, and most processes are subject to a variety of conditions no longer suitable, in the author`s opinion, for the use of optical devices or derivatives of them. This paper describes a continuous extractive technique to measure particulate matter which has been used in Europe and around the word for more than 10 years. This technique works very well in changing particulate matter conditions, low particulate concentrations, small diameter stacks, and stacks/ducts with high water vapor content in the flue gas. 2 refs., 2 figs.

  1. Model Beta 5M: A potential instrumental counterpart to Method 5 for the continuous measurement of particulate matter emissions from combustion and other sources using isokinetic sample extraction technology followed by beta ray attenuation mass measurement techniques

    SciTech Connect

    Griguoli, F.T.

    1997-12-31

    For many years opacity and other values available from optical devices have been used in an attempt to assess and often quantify particulate matter emissions from stationary sources, particularly combustion sources using coal. These opacity values have also been used to obtain mass concentration data. Today`s reality is such that pollution abatement technologies have become better and better, dry or wet, and most processes are subject to a variety of conditions no longer suitable, in the author`s opinion, for the use of optical devices or derivatives of them. This paper describes a continuous extractive technique to measure particulate matter which has been used in Europe and around the world for more than 10 years. This technique works very well in changing particulate matter conditions, low particulate concentrations, small diameter stacks, and stacks/ducts with high water vapor content in the flue gas.

  2. Effects of particulates, heavy metals and acid gas on the removals of NO and PAHs by V2O5-WO3 catalysts in waste incineration system.

    PubMed

    Chang, Feng-Yim; Chen, Jyh-Cherng; Wey, Ming-Yen; Tsai, Shih-An

    2009-10-15

    This study investigated the activities of prepared and commercial V(2)O(5)-WO(3) catalysts for simultaneous removals of NO and polycyclic aromatic hydrocarbons (PAHs) and the influences of particulates, heavy metals, SO(2), and HCl on the performances of catalysts. The experiments were carried out in a laboratory-scale waste incineration system equipped with a catalyst reactor. The DREs of PAHs by prepared and commercial V(2)O(5)-WO(3) catalysts were 64% and 72%, respectively. Increasing the particulate concentrations in flue gas suppressed the DRE of PAHs, but increasing the carbon content on surface of catalysts promotes the NO conversions. The DRE of PAHs by the catalysts was significantly decreased by the increased concentrations of heavy metal Cd, but was promoted by high concentration of Pb. The influence level of SO(2) was higher than HCl on the performances of V(2)O(5)-WO(3) catalysts for PAHs removal, but was lower than HCl for NO removal. Prepared and commercial V(2)O(5)-WO(3) catalysts have similar trends on the effects of particulates, heavy metals, SO(2), and HCl. The results of ESCA analysis reveal that the presence of these pollutants on the surface of catalysts did not change the chemical state of V and W.

  3. Probing Temperature Inside Planar SOFC Short Stack, Modules, and Stack Series

    NASA Astrophysics Data System (ADS)

    Yu, Rong; Guan, Wanbing; Zhou, Xiao-Dong

    2017-02-01

    Probing temperature inside a solid oxide fuel cell (SOFC) stack lies at the heart of the development of high-performance and stable SOFC systems. In this article, we report our recent work on the direct measurements of the temperature in three types of SOFC systems: a 5-cell short stack, a 30-cell stack module, and a stack series consisting of two 30-cell stack modules. The dependence of temperature on the gas flow rate and current density was studied under a current sweep or steady-state operation. During the current sweep, the temperature inside the 5-cell stack decreased with increasing current, while it increased significantly at the bottom and top of the 30-cell stack. During a steady-state operation, the temperature of the 5-cell stack was stable while it was increased in the 30-cell stack. In the stack series, the maximum temperature gradient reached 190°C when the gas was not preheated. If the gas was preheated and the temperature gradient was reduced to 23°C in the stack series with the presence of a preheating gas and segmented temperature control, this resulted in a low degradation rate.

  4. Development of a gas chromatography-mass spectrometry method for the determination of pesticides in gaseous and particulate phases in the atmosphere.

    PubMed

    Borrás, E; Sánchez, P; Muñoz, A; Tortajada-Genaro, L A

    2011-08-05

    A reliable multi-residue method for determining gaseous and particulate phase pesticides in atmospheric samples has been developed. This method, based on full scan gas chromatography-mass spectrometry (GC-MS), allowed the proper determination of sixteen relevant pesticides, in a wide range of concentrations and without the influence of interferences. The pesticides were benfluralin, bitertanol, buprofezin, chlorfenvinphos, chlorpyrifos, chlorpyrifos-methyl, ethalfluralin, fenthion, lindane, malathion, methidathion, propachlor, propanil, pyriproxifen, tebuconazol and trifluralin. Comparisons of two types of sampling filters (quartz and glass fibre) and four types of solid-phase cartridges (XAD-2, XAD-4, Florisil and Orbo-49P) showed that the most suitable supports were glass fibre filter for particulate pesticides and XAD-2 and XAD-4 cartridges for gaseous pesticides (>95% recovery). Evaluations of elution solvents for ultrasonic-assisted extraction demonstrated that isooctane is better than ethylacetate, dichloromethane, methanol or a mixture of acetone:hexane (1:1). Recovery assays and the standard addition method were performed to validate the proposed methodology. Moreover, large simulator chamber experiments allowed the best study of the gas-particle partitioning of pesticides for testing the sampling efficiency for the validation of an analytical multiresidue method for pesticides in air. Satisfactory analytical parameters were obtained, with a repeatability of 5±1%, a reproducibility of 13±3% and detection limits of 0.05-0.18 pg m(-3) for the particulate phase and 26-88 pg m(-3) for the gaseous phase. Finally, the methodology was successfully applied to rural and agricultural samples in the Mediterranean area.

  5. Simultaneous SO{sub 2}/NO/particulate removal from coal combustion gas by solid-state electrochemical technology. Final report

    SciTech Connect

    Cornell, L.P.; Cook, W.J.; Keyvani, M.; Neyman, M.; Helfritch, D.J.

    1991-01-21

    A solid-state electrochemical process now in an early stage of development converts NO{sub x}and SO{sub x} to nitrogen, oxygen, and sulfur. Process objectives are to remove 90+% of SO{sub x} and NO{sub x} and 99% of particulates from Ohio coal combustion flue gases. The electrochemical reactor cell uses ionically conductive ceramics as electrolyte, and electronically conductive materials (including some ceramics) as electrodes; there are no moving parts, no consumable reagents, no by-product sludges, and no process fluids except the flue gas. Downstream of the electro-chemical cell, particulates are removed with a filter or electrostatic precipitator and elemental sulfur is condensed. This work developed and tested electrocatalysts for their ability to selectively reduce SO{sub 2} and NO{sub x} in the presence of oxygen gas in concentrations typical of coal combustion flue gases. Several solid electrolytes and various electrode materials were also tested for use in the electrochemical cell. Gold was chosen as the electrode in the tests because it is porous, resistant to chemical attack, and conductive. Electrocatalyst coatings containing a single transition metal were applied to one inch diameter yttria stabilized ceria disks and tested for NO and SO{sub 2} reduction.

  6. A High Volume Stack Sampler

    NASA Technical Reports Server (NTRS)

    Boubel, Richard W.

    1971-01-01

    The stack sampler described in this paper has been developed to overcome the difficulties of particulate sampling with presently available equipment. Its use on emissions from hog fuel fired boilers, back-fired incinerators, wigwam burners, asphalt plants, and seed cleaning cyclones is reported. The results indicate that the sampler is rapid and reliable in its use. It is relatively simple and inexpensive to operate. For most sources it should be considered over the more complicated and expensive sampling trains being used and specified.

  7. Fuel cell stack arrangements

    DOEpatents

    Kothmann, Richard E.; Somers, Edward V.

    1982-01-01

    Arrangements of stacks of fuel cells and ducts, for fuel cells operating with separate fuel, oxidant and coolant streams. An even number of stacks are arranged generally end-to-end in a loop. Ducts located at the juncture of consecutive stacks of the loop feed oxidant or fuel to or from the two consecutive stacks, each individual duct communicating with two stacks. A coolant fluid flows from outside the loop, into and through cooling channels of the stack, and is discharged into an enclosure duct formed within the loop by the stacks and seals at the junctures at the stacks.

  8. Simultaneous particulates, NO sub x , SO sub x removal from flue gas by all solid-state electrochemical technology

    SciTech Connect

    Cook, W.J.; Hossain, M.S.; Neyman, M. ); Gordon, A.Z. )

    1988-08-31

    The IGR emission control technology controls SOx, NOx, and particulate emissions from coal combustion flue gases. It is based on a solid-state, flow-through, electrochemical reactor which reduces NOx and SO{sub 2} to nitrogen, sulfur, and oxygen. The cell electrolyte is a solid electrolyte, normally a high surface area ceramic oxide-ion conductor. Two tasks were active during this quarter: Task (1) Procurement, Construction and Debugging of the Electrochemical Reactors and Particulate Removal System and Task (2) Electrocatalyst Preparation and Screening Studies. In Task (1) a nine element particulate control apparatus has been constructed and ceramic oxygen ion conducting electrolyte reactor elements have been procured and coated with electrode materials on both the high surface area foam cathode and the flat low surface area anode sides. Task (2) is the screening of electrocatalysts for high oxygen overpotential and low SO{sub 2} and NO{sub x} overpotential. Electrochemical measurements were made with oxide ion conducting ceramic disks in gases containing NO{sub x} and oxygen and ex-situ FT-IR was used to verify the electrochemical reduction rates. 1 refs., 10 figs., 6 tabs.

  9. Simultaneous particulates, NO sub x , SO sub x removal from flue gas by all solid-state electrochemical technology

    SciTech Connect

    Cook, W.J.; Hossain, M.S.; Neyman, M. ); Gordon, A.Z. )

    1988-11-21

    The IGR emission control technology controls SOx, NOx, and particulate emissions from coal combustion flue gases. It is based on a solid-state, flow-through, electrochemical reactor which reduces NOx and SO{sub 2} to nitrogen, sulfur, and oxygen. The cell electrolyte is a solid electrolyte, normally a high surface area ceramic oxide-ion conductor. Two tasks were active during this quarter: Task, Procurement, Construction and Debugging of the Electrochemical Reactors and Particulate Removal System and Task, Electrocatalyst Preparation and Screening Studies. In Task a nine element particulate control apparatus is ready for testing with oxide ion conducting pieces and a test apparatus has been setup to test ceramic oxygen ion conducting electrolyte reactor elements. Task is the screening of electrocatalysts for high oxygen overpotential and low SO{sub 2} and NO{sub x} overpotential. Electrochemical measurements were made with oxide ion conducting ceramic disks using a series of electrocatalysts in gases containing NO, SO{sub 2} and oxygen. 1 ref., 3 tabs.

  10. Optimization of manifold design for 1 kW-class flat-tubular solid oxide fuel cell stack operating on reformed natural gas

    NASA Astrophysics Data System (ADS)

    Rashid, Kashif; Dong, Sang Keun; Khan, Rashid Ali; Park, Seung Hwan

    2016-09-01

    This study focuses on optimizing the manifold design for a 1 kW-class flat-tubular solid oxide fuel cell stack by performing extensive three-dimensional numerical simulations on numerous manifold designs. The stack flow uniformity and the standard flow deviation indexes are implemented to characterize the flow distributions in the stack and among the channels of FT-SOFC's, respectively. The results of the CFD calculations demonstrate that the remodeled manifold without diffuser inlets and 6 mm diffuser front is the best among investigated designs with uniformity index of 0.996 and maximum standard flow deviation of 0.423%. To understand the effect of manifold design on the performance of stack, both generic and developed manifold designs are investigated by applying electrochemical and internal reforming reactions modeling. The simulation results of the stack with generic manifold are validated using experimental data and then validated models are adopted to simulate the stack with the developed manifold design. The results reveal that the stack with developed manifold design achieves more uniform distribution of species, temperature, and current density with comparatively lower system pressure drop. In addition, the results also showed ∼8% increase in the maximum output power due to the implementation of uniform fuel velocity distributions in the cells.

  11. Seasonal variation and spatial distribution of atmospheric mercury and its gas-particulate partition in the vicinity of a semiconductor manufacturing complex.

    PubMed

    Jen, Yi-Hsiu; Chen, Wei-Hsiang; Yuan, Chung-Shin; Ie, Iau-Ren; Hung, Chung-Hsuang

    2014-04-01

    This study investigated the tempospatial variation of atmospheric mercury and its gas-particulate partition in the vicinity of a semiconductor manufacturing complex, where a plenty of flat-monitor manufacturing plants using elemental mercury as a light-initiating medium to produce backlight fluorescence tubes and may fugitively emit mercury-containing air pollutants to the atmosphere. Atmospheric mercury speciation, concentration, and the partition of total gaseous mercury (TGM) and particulate mercury (Hgp) were measured at four sites surrounding the semiconductor manufacturing intensive district/complex. One-year field measurement showed that the seasonal averaged concentrations of TGM and Hgp were in the range of 3.30-6.89 and 0.06-0.14 ng/m(3), respectively, whereas the highest 24-h TGM and Hgp concentrations were 10.33 and 0.26 ng/m(3), respectively. Atmospheric mercury apportioned as 92.59-99.01 % TGM and 0.99-7.41 % Hgp. As a whole, the highest and lowest concentrations of TGM were observed in the winter and summer sampling periods, respectively, whereas the concentration of Hgp did not vary much seasonally. The highest TGM concentrations were always observed at the downwind sites, indicating that the semiconductor manufacturing complex was a hot spot of mercury emission source, which caused severe atmospheric mercury contamination over the investigation region.

  12. Analysis of semi-volatile organic compounds in indoor suspended particulate matter by thermal desorption coupled with gas chromatography/mass spectrometry.

    PubMed

    Mercier, Fabien; Glorennec, Philippe; Blanchard, Olivier; Le Bot, Barbara

    2012-09-07

    People are exposed to multiple pollutants, especially indoors. In the perspective of a cumulative risk assessment, a multi-residue analytical method was developed to assess the contamination of indoor suspended particulate matter by 55 semi-volatile organic compounds (SVOCs) including musk fragrances, organochlorines (OCs), organophosphates (OPs), polycyclic aromatic hydrocarbons (PAHs), polybromodiphenylethers (PBDEs), polychlorobiphenyls (PCBs), phthalates and pyrethroids. It is based on thermal desorption (TD) coupled with gas chromatography/mass spectrometry (GC/MS). Once the thermal desorption conditions were optimized, the method was validated in terms of quantification limits and accuracy using a standard reference material (SRM 2585). Instrumental quantification limits were 10 pg (some OCs, some pyrethroids, musk fragrances, OPs, PAHs, PBDEs and PCBs), 100 pg (phthalates and other OCs) and 1000 pg (other pyrethroids) corresponding respectively to method quantification limits of 1, 10, and 100 pg/m³ for a sampled air volume of 20 m³. Calibration quadratic curves for ranges of 10-1000, 100-10,000, and 1000-100,000 pg, depending on the substance, exhibit determination coefficients above 0.999. Recoveries were between 61 and 96% for chlorinated pesticides, PAHs, PBDEs and PCBs present in the SRM 2585. A test of the method on indoor particulate matter samples (PM₁₀) collected on quartz fiber filters in French dwellings demonstrated its ability to quantify SVOCs from a small amount of PM.

  13. Prediction of temperature profile in MCFC stack

    SciTech Connect

    Lee, Kab Soo; Kim, Hwayong; Hong, Seong-An; Lim, Hee Chun

    1996-12-31

    A simple three dimensional model was developed to simulate the temperature distribution and the performance of various flow types of the MCFC stack. The objective of this study was to understand the complicated phenomena occurring in the MCFC stack and to supply the basic data for optimizing the operating condition of the MCFC stack. Assuming that the stack consists of a number of differential elements which have uniform temperature and gas composition, the model was solved by finite difference method. The performance of this model was demonstrated by comparing the calculated value with experimental data of the 1.5kW class co-flow type MCFC stack operated in KIST. This model can be utilized as a simple diagnostic tool in case of the operational abnormality such as the hot spot which often occurs inside the stack.

  14. Gas-phase and particulate products from the atmospheric degradation of the organothiophosphorus insecticide chlorpyrifos-methyl.

    PubMed

    Borrás, Esther; Tortajada-Genaro, Luis Antonio; Ródenas, Milagros; Vera, Teresa; Coscollá, Clara; Yusá, Vicent; Muñoz, Amalia

    2015-11-01

    The phosphorothioate structure is highly present in several organophosphorus pesticides. However, there is insufficient information about its degradation process after the release to the atmosphere and the secondary pollutants formed. Herein, the atmospheric reaction of chlorpyrifos-methyl (o,o-dimethyl o-(3,5,6-trichloropyridin-2-yl) phosphorothioate), is described for semi-urban or rural locations. The photo-oxidation under low NOx conditions (5-55 ppbV) was reproduced in a large outdoor simulation chamber, observing a rapid degradation (lifetime<3.5 h). The formation of gaseous products and particulate matter (aerosol yield 2-8%) was monitored. The chemical composition of minor products (gaseous and particulate) was studied, identifying 15 multi-oxygenated derivatives. The most abundant products were ring-retaining molecules such as o,o-dimethyl o-(3,5,6-trichloropyridin-2-yl) phosphorothioate, dimethyl 3,5,6-trichloropyridin-2-yl phosphate, o-methyl o-(3,5,6-trichloropyridin-2-yl) hydrogen phosphorothioate, 3,5,6-trichloropyridin-2-yl dihydrogen phosphate, 3,5,6-trichloropyridin-2-ol, and 3,5,6-trichloropyridine-2,4-diol. An atmospheric degradation mechanism has been proposed based on an oxidation started with OH-nucleophilic attack to P=S bond. The results have been extrapolated to other organothiophosphorus molecules, such as malathion, parathion, diazinon and methidathion, among many others, to estimate their photo-oxidative degradation and the expected products.

  15. Particulate and trace gas emissions from prescribed burns in southeastern U.S. fuel types: Summary of a 5-year project

    SciTech Connect

    Weise, David; Johnson, Timothy J.; Reardon, James

    2015-03-04

    Management of smoke from prescribed fires requires knowledge of fuel quantity and the amount and composition of the smoke produced by the fire to minimize adverse impacts on human health. A five-year study produced new emissions information for more than 100 trace gases and particulate matter in smoke for fuel types found in the southern United States of America using state-of-the-art instrumentation in both laboratory and field experiments. Emission factors for flaming, smoldering, and residual smoldering were developed. Agreement between laboratory and field-derived emission factors was generally good in most cases. Reference spectra of over 50 wildland fire gas-phase smoke components were added to a publicly-available database to support identification via infrared spectroscopy. Fuel loading for the field experiments was similar to previously measured fuels. This article summarizes the results of a five-year study to better understand the composition of smoke during all phases of burning for such forests.

  16. 40 CFR 86.109-94 - Exhaust gas sampling system; Otto-cycle vehicles not requiring particulate emission measurements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...), and associated valves, pressure and temperature sensors. The PDP-CVS shall conform to the following... and may be required for natural gas-fueled and liquefied petroleum gas-fueled vehicles. Procedures for..., and assorted valves, and pressure and temperature sensors. The CFV sample system shall conform to...

  17. Stack Monitor Operating Experience Review

    SciTech Connect

    L. C. Cadwallader; S. A. Bruyere

    2009-05-01

    Stack monitors are used to sense radioactive particulates and gases in effluent air being vented from rooms of nuclear facilities. These monitors record the levels and types of effluents to the environment. This paper presents the results of a stack monitor operating experience review of the U.S. Department of Energy (DOE) Occurrence Reporting and Processing System (ORPS) database records from the past 18 years. Regulations regarding these monitors are briefly described. Operating experiences reported by the U.S. DOE and in engineering literature sources were reviewed to determine the strengths and weaknesses of these monitors. Electrical faults, radiation instrumentation faults, and human errors are the three leading causes of failures. A representative “all modes” failure rate is 1E-04/hr. Repair time estimates vary from an average repair time of 17.5 hours (with spare parts on hand) to 160 hours (without spare parts on hand). These data should support the use of stack monitors in any nuclear facility, including the National Ignition Facility and the international ITER project.

  18. Simultaneous particulates, NO sub x , SO sub x removal from flue gas by all solid-state electrochemical technology

    SciTech Connect

    Cook, W.J.; Hossain, S.; Neyman, M. ); Gordon, A.Z. )

    1988-02-18

    The IGR emission control technology controls SOx, NOx, and particulate emissions from coal combustion flue gases. It is based on a solid-state, flow-through, electrochemical reactor which reduces NO{sub x} and SO{sub 2} to nitrogen, sulfur, and oxygen cell. The cell electrolyte is a solid-electrolyte, normally a high surface area ceramic oxide-ion conductor. Tasks this quarter include: Project Work Plan and Electrocatalyst Preparation and Screening Studies of electrocatalysts for high oxygen overpotential and low SO{sub 2} and NO{sub x} overpotential. Tests will be conducted with ceramic disks one inch in diameter. The reactor for disk testing has been built and the disks have been aquired. 4 refs., 9 figs.

  19. DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS-FIRED COMBUSTION SYSTEMS

    SciTech Connect

    Glenn C. England; Stephanie Wien; Mingchih O. Chang

    2002-08-01

    This report provides results from the first year of this three-year project to develop dilution measurement technology for characterizing PM2.5 (particles with aerodynamic diameter smaller than 2.5 micrometers) and precursor emissions from stationary combustion sources used in oil, gas and power generation operations. Detailed emission rate and chemical speciation test results for a refinery gas-fired process heater and plans for cogeneration gas turbine tests and pilot-scale tests are presented. Tests were performed using a research dilution sampling apparatus and traditional EPA methods to compare PM2.5 mass and chemical speciation. Test plans are presented for a gas turbine facility that will be tested in the fourth quarter of 2002. A preliminary approach for pilot-scale tests is presented that will help define design constraints for a new dilution sampler design that is smaller, lighter, and less costly to use.

  20. Polycyclic aromatic hydrocarbons in gas and particulate phases of indoor environments influenced by tobacco smoke: Levels, phase distributions, and health risks

    NASA Astrophysics Data System (ADS)

    Castro, Dionísia; Slezakova, Klara; Delerue-Matos, Cristina; Alvim-Ferraz, Maria da Conceição; Morais, Simone; Pereira, Maria do Carmo

    2011-04-01

    As polycyclic aromatic hydrocarbons (PAHs) have a negative impact on human health due to their mutagenic and/or carcinogenic properties, the objective of this work was to study the influence of tobacco smoke on levels and phase distribution of PAHs and to evaluate the associated health risks. The air samples were collected at two homes; 18 PAHs (the 16 PAHs considered by U.S. EPA as priority pollutants, dibenzo[a,l]pyrene and benzo[j]fluoranthene) were determined in gas phase and associated with thoracic (PM 10) and respirable (PM 2.5) particles. At home influenced by tobacco smoke the total concentrations of 18 PAHs in air ranged from 28.3 to 106 ng m -3 (mean of 66.7 ± 25.4 ng m -3), ∑ PAHs being 95% higher than at the non-smoking one where the values ranged from 17.9 to 62.0 ng m -3 (mean of 34.5 ± 16.5 ng m -3). On average 74% and 78% of ∑ PAHs were present in gas phase at the smoking and non-smoking homes, respectively, demonstrating that adequate assessment of PAHs in air requires evaluation of PAHs in both gas and particulate phases. When influenced by tobacco smoke the health risks values were 3.5-3.6 times higher due to the exposure of PM 10. The values of lifetime lung cancer risks were 4.1 × 10 -3 and 1.7 × 10 -3 for the smoking and non-smoking homes, considerably exceeding the health-based guideline level at both homes also due to the contribution of outdoor traffic emissions. The results showed that evaluation of benzo[a]pyrene alone would probably underestimate the carcinogenic potential of the studied PAH mixtures; in total ten carcinogenic PAHs represented 36% and 32% of the gaseous ∑ PAHs and in particulate phase they accounted for 75% and 71% of ∑ PAHs at the smoking and non-smoking homes, respectively.

  1. 40 CFR 86.210-08 - Exhaust gas sampling system; Diesel-cycle vehicles not requiring particulate emissions measurements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... constant mass flow system must be used to ensure a proportional THC measurement. (2) For natural gas-fueled... than 355 °F). This will be determined by a temperature sensor located on a section of the probe wall outside of the walls of the sampling system. The temperature sensor shall be insulated from any...

  2. 40 CFR 86.210-08 - Exhaust gas sampling system; Diesel-cycle vehicles not requiring particulate emissions measurements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Vehicles; Cold Temperature Test Procedures § 86.210-08 Exhaust gas sampling system; Diesel-cycle vehicles... the THC probe be free from cold spots (i.e., free from spots where the probe wall temperature is less... common sample pump is used for all analyzers and the sample line system design reflects good...

  3. 40 CFR 86.210-08 - Exhaust gas sampling system; Diesel-cycle vehicles not requiring particulate emissions measurements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Vehicles; Cold Temperature Test Procedures § 86.210-08 Exhaust gas sampling system; Diesel-cycle vehicles... the THC probe be free from cold spots (i.e., free from spots where the probe wall temperature is less... common sample pump is used for all analyzers and the sample line system design reflects good...

  4. Regenerable particulate filter

    DOEpatents

    Stuecker, John N.; Cesarano, III, Joseph; Miller, James E.

    2009-05-05

    A method of making a three-dimensional lattice structure, such as a filter used to remove particulates from a gas stream, where the physical lattice structure is designed utilizing software simulation from pre-defined mass transfer and flow characteristics and the designed lattice structure is fabricated using a free-form fabrication manufacturing technique, where the periodic lattice structure is comprised of individual geometric elements.

  5. Co-flow planar SOFC fuel cell stack

    DOEpatents

    Chung, Brandon W.; Pham, Ai Quoc; Glass, Robert S.

    2004-11-30

    A co-flow planar solid oxide fuel cell stack with an integral, internal manifold and a casing/holder to separately seal the cell. This construction improves sealing and gas flow, and provides for easy manifolding of cell stacks. In addition, the stack construction has the potential for an improved durability and operation with an additional increase in cell efficiency. The co-flow arrangement can be effectively utilized in other electrochemical systems requiring gas-proof separation of gases.

  6. Application of Ion Mobility Mass Spectrometry for Identification of Gas and Particulate Phase Organic Species in the Atmosphere

    NASA Astrophysics Data System (ADS)

    Canagaratna, M. R.; Krechmer, J.; Groessl, M.; Junninen, H.; Kimmel, J.; Cubison, M.; Massoli, P.; Lin, Y. H.; Zhang, H.; Lambe, A. T.; Zhang, X.; Knochenmuss, R.; Surratt, J. D.; Jimenez, J. L.; Worsnop, D. R.

    2015-12-01

    We present recent results obtained from the application of an ion mobility time-of-flight mass spectrometer (IMS-TOF) to the detection of oxidized organic species in the atmosphere. Ion mobility mass spectrometry separates ions on the basis of their interactions with buffer gases on millisecond time scales and allows for detailed separation and identification of isomeric and isobaric molecules. Detection of highly oxidized gas phase organics is achieved by coupling the IMS-TOF to a chemical ionization scheme that utilized NO3- as the reagent ion. Oxidized gas phase molecules produced from biogenic precursors were chemically characterized with this technique during the Southern Oxidant and Aerosol Study (SOAS) field campaign as well as in laboratory experiments utilizing a potential aerosol mass (PAM) reactor. The application of IMS-TOF to aerosol phase organic species is also presented. While molecular composition of fine aerosol is often obtained by combining gas or liquid chromatography (GC or LC) with mass spectrometric detection, these techniques are limited in their ability to transfer, resolve and identify water soluble organic carbon (WSOC) species which account for a significant portion of aerosol mass. Here we demonstrate IMS as a promising alternative approach for obtaining detailed information about organic aerosol (OA) constituent species. We examine aerosol particles collected on filters during ambient and laboratory measurements. The filter extracts are subjected to electrospray ionization (ESI) before detection with the IMS-TOF. The capability of this technique to resolve WSOC species, isomers, and oligomers is highlighted.

  7. Stacking with stochastic cooling

    NASA Astrophysics Data System (ADS)

    Caspers, Fritz; Möhl, Dieter

    2004-10-01

    Accumulation of large stacks of antiprotons or ions with the aid of stochastic cooling is more delicate than cooling a constant intensity beam. Basically the difficulty stems from the fact that the optimized gain and the cooling rate are inversely proportional to the number of particles 'seen' by the cooling system. Therefore, to maintain fast stacking, the newly injected batch has to be strongly 'protected' from the Schottky noise of the stack. Vice versa the stack has to be efficiently 'shielded' against the high gain cooling system for the injected beam. In the antiproton accumulators with stacking ratios up to 105 the problem is solved by radial separation of the injection and the stack orbits in a region of large dispersion. An array of several tapered cooling systems with a matched gain profile provides a continuous particle flux towards the high-density stack core. Shielding of the different systems from each other is obtained both through the spatial separation and via the revolution frequencies (filters). In the 'old AA', where the antiproton collection and stacking was done in one single ring, the injected beam was further shielded during cooling by means of a movable shutter. The complexity of these systems is very high. For more modest stacking ratios, one might use azimuthal rather than radial separation of stack and injected beam. Schematically half of the circumference would be used to accept and cool new beam and the remainder to house the stack. Fast gating is then required between the high gain cooling of the injected beam and the low gain stack cooling. RF-gymnastics are used to merge the pre-cooled batch with the stack, to re-create free space for the next injection, and to capture the new batch. This scheme is less demanding for the storage ring lattice, but at the expense of some reduction in stacking rate. The talk reviews the 'radial' separation schemes and also gives some considerations to the 'azimuthal' schemes.

  8. Gas-phase ammonia and water-soluble ions in particulate matter analysis in an urban vehicular tunnel.

    PubMed

    Vieira-Filho, Marcelo S; Ito, Debora T; Pedrotti, Jairo J; Coelho, Lúcia H G; Fornaro, Adalgiza

    2016-10-01

    Ammonia is a key alkaline species, playing an important role by neutralizing atmospheric acidity and inorganic secondary aerosol production. On the other hand, the NH3/NH4 (+) increases the acidity and eutrophication in natural ecosystems, being NH3 classified as toxic atmospheric pollutant. The present study aims to give a better comprehension of the nitrogen content species distribution in fine and coarse particulate matter (PM2.5 and PM2.5-10) and to quantify ammonia vehicular emissions from an urban vehicular tunnel experiment in the metropolitan area of São Paulo (MASP). MASP is the largest megacity in South America, with over 20 million inhabitants spread over 2000 km(2) of urbanized area, which faces serious environmental problems. The PM2.5 and PM2.5-10 median mass concentrations were 44.5 and 66.6 μg m(-3), respectively, during weekdays. In the PM2.5, sulfate showed the highest concentration, 3.27 ± 1.76 μg m(-3), followed by ammonium, 1.14 ± 0.71 μg m(-3), and nitrate, 0.80 ± 0.52 μg m(-3). Likewise, the dominance (30 % of total PM2.5) of solid species, mainly the ammonium salts, NH4HSO4, (NH4)2SO4, and NH4NO3, resulted from simulation of inorganic species. The ISORROPIA simulation was relevant to show the importance of environment conditions for the ammonium phase distribution (solid/aqueous), which was solely aqueous at outside and almost entirely solid at inside tunnel. Regarding gaseous ammonia concentrations, the value measured inside the tunnel (46.5 ± 17.5 μg m(-3)) was 3-fold higher than that outside (15.2 ± 11.3 μg m(-3)). The NH3 vehicular emission factor (EF) estimated by carbon balance for urban tunnel was 44 ± 22 mg km(-1). From this EF value and considering the MASP traffic characteristics, it was possible to estimate more than 7 Gg NH3 year(-1) emissions that along with NOx are likely to cause rather serious problems to natural ecosystems in the region.

  9. 40 CFR 60.1780 - How are the stack test data used?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Small Municipal Waste Combustion Units Constructed on or Before August 30, 1999 Model Rule-Stack Testing..., cadmium, lead, mercury, particulate matter, opacity, hydrogen chloride, and fugitive ash to...

  10. Impact of alternative fuels on emissions characteristics of a gas turbine engine - part 1: gaseous and particulate matter emissions.

    PubMed

    Lobo, Prem; Rye, Lucas; Williams, Paul I; Christie, Simon; Uryga-Bugajska, Ilona; Wilson, Christopher W; Hagen, Donald E; Whitefield, Philip D; Blakey, Simon; Coe, Hugh; Raper, David; Pourkashanian, Mohamed

    2012-10-02

    Growing concern over emissions from increased airport operations has resulted in a need to assess the impact of aviation related activities on local air quality in and around airports, and to develop strategies to mitigate these effects. One such strategy being investigated is the use of alternative fuels in aircraft engines and auxiliary power units (APUs) as a means to diversify fuel supplies and reduce emissions. This paper summarizes the results of a study to characterize the emissions of an APU, a small gas turbine engine, burning conventional Jet A-1, a fully synthetic jet fuel, and other alternative fuels with varying compositions. Gas phase emissions were measured at the engine exit plane while PM emissions were recorded at the exit plane as well as 10 m downstream of the engine. Five percent reduction in NO(x) emissions and 5-10% reduction in CO emissions were observed for the alternative fuels. Significant reductions in PM emissions at the engine exit plane were achieved with the alternative fuels. However, as the exhaust plume expanded and cooled, organic species were found to condense on the PM. This increase in organic PM elevated the PM mass but had little impact on PM number.

  11. Impact of alternative fuels on emissions characteristics of a gas turbine engine - part 2: volatile and semivolatile particulate matter emissions.

    PubMed

    Williams, Paul I; Allan, James D; Lobo, Prem; Coe, Hugh; Christie, Simon; Wilson, Christopher; Hagen, Donald; Whitefield, Philip; Raper, David; Rye, Lucas

    2012-10-02

    The work characterizes the changes in volatile and semivolatile PM emissions from a gas turbine engine resulting from burning alternative fuels, specifically gas-to-liquid (GTL), coal-to-liquid (CTL), a blend of Jet A-1 and GTL, biodiesel, and diesel, to the standard Jet A-1. The data presented here, compares the mass spectral fingerprints of the different fuels as measured by the Aerodyne high resolution time-of-flight aerosol mass spectrometer. There were three sample points, two at the exhaust exit plane with dilution added at different locations and another probe located 10 m downstream. For emissions measured at the downstream probe when the engine was operating at high power, all fuels produced chemically similar organic PM, dominated by C(x)H(y) fragments, suggesting the presence of long chain alkanes. The second largest contribution came from C(x)H(y)O(z) fragments, possibly from carbonyls or alcohols. For the nondiesel fuels, the highest loadings of organic PM were from the downstream probe at high power. Conversely, the diesel based fuels produced more organic material at low power from one of the exit plane probes. Differences in the composition of the PM for certain fuels were observed as the engine power decreased to idle and the measurements were made closer to the exit plane.

  12. Application of an automatic thermal desorption-gas chromatography-mass spectrometry system for the analysis of polycyclic aromatic hydrocarbons in airborne particulate matter.

    PubMed

    Gil-Moltó, J; Varea, M; Galindo, N; Crespo, J

    2009-02-27

    The application of the thermal desorption (TD) method coupled with gas chromatography-mass spectrometry (GC-MS) to the analysis of aerosol organics has been the focus of many studies in recent years. This technique overcomes the main drawbacks of the solvent extraction approach such as the use of large amounts of toxic organic solvents and long and laborious extraction processes. In this work, the application of an automatic TD-GC-MS instrument for the determination of particle-bound polycyclic aromatic hydrocarbons (PAHs) is evaluated. This device offers the advantage of allowing the analysis of either gaseous or particulate organics without any modification. Once the thermal desorption conditions for PAH extraction were optimised, the method was verified on NIST standard reference material (SRM) 1649a urban dust, showing good linearity, reproducibility and accuracy for all target PAHs. The method has been applied to PM10 and PM2.5 samples collected on quartz fibre filters with low volume samplers, demonstrating its capability to quantify PAHs when only a small amount of sample is available.

  13. Simulating gas and particulate pollution over the Middle East and the state of Qatar using a 3-D regional air quality modeling system

    NASA Astrophysics Data System (ADS)

    Fountoukis, Christos; Gladich, Ivan; Ayoub, Mohammed; Kais, Sabre; Ackermann, Luis; Skillern, Adam

    2016-04-01

    The rapid urbanization, industrialization and economic expansion in the Middle East have led to increased levels of atmospheric pollution with important implications for human health and climate. We applied the online-coupled meteorological and chemical transport Weather Research and Forecasting/Chemistry (WRF-Chem) model over the Middle Eastern domain, to simulate the concentration of gas and aerosols with a special focus over the state of Qatar. WRF-Chem was set to simulate pollutant concentrations along with the meteorology-chemistry interactions through the related direct, indirect and semi-direct feedback mechanisms. A triple-nested domain configuration was used with a high grid resolution (1x1 km2) over the region of Qatar. Model predictions are evaluated against intensive measurements of meteorological parameters (temperature, relative humidity and wind speed) as well as ozone and particulate matter taken from various measurement stations throughout Doha, Qatar during summer 2015. The ability of the model to capture the temporal and spatial variability of the observations is assessed and possible reasons for the model bias are explored through sensitivity tests. Emissions of both fine and coarse mode particles from construction activities in large urban Middle Eastern environments comprise a major pollution source that is unaccounted for in emission inventories used so far in large scale models for this part of the world.

  14. Environmental assessment of three egg production systems--Part II. Ammonia, greenhouse gas, and particulate matter emissions.

    PubMed

    Shepherd, T A; Zhao, Y; Li, H; Stinn, J P; Hayes, M D; Xin, H

    2015-03-01

    As an integral part of the Coalition for Sustainable Egg Supply (CSES) Project, this study simultaneously monitored air emissions of 3 commercially operated egg production systems at the house level and associated manure storage over 2 single-cycle flocks (18 to 78 wk of age). The 3 housing systems were 1) a conventional cage house (CC) with a 200,000-hen capacity (6 hens in a cage at a stocking density of 516 cm2/hen), 2) an enriched colony house (EC) with a 50,000-hen capacity (60 hens per colony at a stocking density of 752 cm2/hen), and 3) an aviary house (AV) with a 50,000-hen capacity (at a stocking density of 1253 to 1257 cm2/hen). The 3 hen houses were located on the same farm and were populated with Lohmann white hens of the same age. Indoor environment and house-level gaseous (ammonia [NH3] and greenhouse gasses [GHG], including carbon dioxide [CO2], methane [CH4], and nitrous oxide [N2O]) and particulate matter (PM10, PM2.5) emissions were monitored continually. Gaseous emissions from the respective manure storage of each housing system were also monitored. Emission rates (ERs) are expressed as emission quantities per hen, per animal unit (AU, 500 kg live BW), and per kilogram of egg output. House-level NH3 ER (g/hen/d) of EC (0.054) was significantly lower than that of CC (0.082) or AV (0.112) (P<0.05). The house-level CO2 ER (g/hen/d) was lower for CC (68.3) than for EC and AV (74.4 and 74.0, respectively), and the CH4 ER (g/hen/d) was similar for all 3 houses (0.07 to 0.08). The house-level PM ER (mg/hen/d), essentially representing the farm-level PM ER, was significantly higher for AV (PM10 100.3 and PM2.5 8.8) than for CC (PM10 15.7 and PM2.5 0.9) or EC (PM10 15.6 and PM2.5 1.7) (P<0.05). The farm-level (house plus manure storage) NH3 ER (g/hen/d) was significantly lower for EC (0.16) than for CC (0.29) or AV (0.30) (P<0.05). As expected, the magnitudes of GHG emissions were rather small for all 3 production systems. Data from this study enable

  15. Environmental assessment of three egg production systems — Part II. Ammonia, greenhouse gas, and particulate matter emissions

    PubMed Central

    Shepherd, T. A.; Zhao, Y.; Li, H.; Stinn, J. P.; Hayes, M. D.; Xin, H.

    2015-01-01

    As an integral part of the Coalition for Sustainable Egg Supply (CSES) Project, this study simultaneously monitored air emissions of 3 commercially operated egg production systems at the house level and associated manure storage over 2 single-cycle flocks (18 to 78 wk of age). The 3 housing systems were 1) a conventional cage house (CC) with a 200,000-hen capacity (6 hens in a cage at a stocking density of 516 cm2/hen), 2) an enriched colony house (EC) with a 50,000-hen capacity (60 hens per colony at a stocking density of 752 cm2/hen), and 3) an aviary house (AV) with a 50,000-hen capacity (at a stocking density of 1253 to 1257 cm2/hen). The 3 hen houses were located on the same farm and were populated with Lohmann white hens of the same age. Indoor environment and house-level gaseous (ammonia [NH3] and greenhouse gasses [GHG], including carbon dioxide [CO2], methane [CH4], and nitrous oxide [N2O]) and particulate matter (PM10, PM2.5) emissions were monitored continually. Gaseous emissions from the respective manure storage of each housing system were also monitored. Emission rates (ERs) are expressed as emission quantities per hen, per animal unit (AU, 500 kg live BW), and per kilogram of egg output. House-level NH3 ER (g/hen/d) of EC (0.054) was significantly lower than that of CC (0.082) or AV (0.112) (P < 0.05). The house-level CO2 ER (g/hen/d) was lower for CC (68.3) than for EC and AV (74.4 and 74.0, respectively), and the CH4 ER (g/hen/d) was similar for all 3 houses (0.07 to 0.08). The house-level PM ER (mg/hen/d), essentially representing the farm-level PM ER, was significantly higher for AV (PM10 100.3 and PM2.5 8.8) than for CC (PM10 15.7 and PM2.5 0.9) or EC (PM10 15.6 and PM2.5 1.7) (P < 0.05). The farm-level (house plus manure storage) NH3 ER (g/hen/d) was significantly lower for EC (0.16) than for CC (0.29) or AV (0.30) (P < 0.05). As expected, the magnitudes of GHG emissions were rather small for all 3 production systems. Data from this study

  16. Assessing the co-benefits of greenhouse gas reduction: health benefits of particulate matter related inspection and maintenance programs in Bangkok, Thailand.

    PubMed

    Li, Ying; Crawford-Brown, Douglas J

    2011-04-15

    Since the 1990s, the capital city of Thailand, Bangkok has been suffering from severe ambient particulate matter (PM) pollution mainly attributable to its wide use of diesel-fueled vehicles and motorcycles with poor emission performance. While the Thai government strives to reduce emissions from transportation through enforcing policy measures, the link between specific control policies and associated health impacts is inadequately studied. This link is especially important in exploring the co-benefits of greenhouse gas emissions reductions, which often brings reduction in other pollutants such as PM. This paper quantifies the health benefits potentially achieved by the new PM-related I/M programs targeting all diesel vehicles and motorcycles in the Bangkok Metropolitan Area (BMA). The benefits are estimated by using a framework that integrates policy scenario development, exposure assessment, exposure-response assessment and economic valuation. The results indicate that the total health damage due to the year 2000 PM emissions from vehicles in the BMA was equivalent to 2.4% of Thailand's GDP. Under the business-as-usual (BAU) scenario, total vehicular PM emissions in the BMA will increase considerably over time due to the rapid growth in vehicle population, even if the fleet average emission rates are projected to decrease over time as the result of participation of Thailand in post-Copenhagen climate change strategies. By 2015, the total health damage is estimated to increase by 2.5 times relative to the year 2000. However, control policies targeting PM emissions from automobiles, such as the PM-oriented I/M programs, could yield substantial health benefits relative to the BAU scenario, and serve as co-benefits of greenhouse gas control strategies. Despite uncertainty associated with the key assumptions used to estimate benefits, we find that with a high level confidence, the I/M programs will produce health benefits whose economic impacts considerably outweigh

  17. Surface Energy Determined by Inverse Gas Chromatography as a Tool to Investigate Particulate Interactions in Dry Powder Inhalers.

    PubMed

    Das, Shyamal C; Tucker, Ian G; Stewart, Peter J

    2015-01-01

    Dry powder inhalers (DPIs) usually contain drug particles <6 µm which agglomerate and/ or adhere on the surfaces of large carriers particles. The detachment of drug particles from carriers and de-agglomeration of drug particles into primary particles is essential for drug deposition in the deep lung. These processes are influenced by the surface energy of particles. Inverse gas chromatography (IGC) has been used to determine the surface energy of powder particles used in DPI to characterize materials and to understand aerosolization behaviour. Early studies used an infinite dilution technique to determine nonpolar surface energy and free energy of adsorption for polar interactions separately. Although some correlations were observed with the change in nonpolar surface energy before and after micronization, milling and storage, a lack of consistency in the change of free energy of adsorption was common. Moreover, a consistent relationship between complex de-agglomeration behaviour and surface energy has not been established and there are even some examples of negative correlation. In fact, nonpolar surface energy at infinite dilution is an incomplete representation of powder surface characteristics. The techniques for measuring polar surface energy, total surface energy and surface energy distribution have provided more revealing information about surface energetics of powders. Surface energy distributions determined by IGC or surface energy analyser have been successfully used to understand energetic heterogeneity of surfaces, characterize different polymorphs and understand changes due to micronization, structural relaxation, dry coating and storage. Efforts have been made to utilize surface energy distribution data to calculate powder strength distribution and to explain complex de-agglomeration behaviour of DPI formulations.

  18. Particulate hot gas stream cleanup technical issues: Task 1.0, Assessment of ash characteristics. Quarterly report, October-- December 1994

    SciTech Connect

    1995-03-01

    This is the first in a series of quarterly reports describing the activities performed under Task 1. The analyses of Hot Gas Stream Cleanup (HGCU) ashes and descriptions of filter performance presented in this report were designed to address the problems with filter operation that are apparently linked to the characteristics of the collected ash. This task is designed to generate a data base of the key characteristics of ashes collected from operating advanced particle filters (APF`s) and to relate these ash properties to the operation and performance of these filters and their components. Observations of the filter assembly during site visits to the Tidd Demonstration Plant APF have led to the conclusion that that tenacious ash deposits that form in the APF apparently induce stresses that result in bent and/or broken ceramic candle filter elements. A site visit, was made to the Tidd APF on October 27, 1994 to collect ash samples from various locations in the filter vessel and to document the condition of the APF. A variety of laboratory analyses were performed on ash samples collected during this site visit to assess whether recent attempts to introduce larger particles into the ash deposits by derating the cyclone upstream of the APF have been successful. Some particles larger than 45 Jim were identified in various ash samples from the APF, but they account for less than 5 % of the mass of the ash. Although Scanning Electron Microscope EDX spectra and elemental maps lack the resolution to identify the bonds between particles in the ash agglomerates found in the APF, an excellent stereographic image of the structure of an ash nodule collected from the APF was generated with the Scanning Electron Microscope. The stereographic image was very enlightening as to the structure of the nodule.

  19. Advanced particulate matter control apparatus and methods

    DOEpatents

    Miller, Stanley J [Grand Forks, ND; Zhuang, Ye [Grand Forks, ND; Almlie, Jay C [East Grand Forks, MN

    2012-01-10

    Apparatus and methods for collection and removal of particulate matter, including fine particulate matter, from a gas stream, comprising a unique combination of high collection efficiency and ultralow pressure drop across the filter. The apparatus and method utilize simultaneous electrostatic precipitation and membrane filtration of a particular pore size, wherein electrostatic collection and filtration occur on the same surface.

  20. Size Distribution An Gas/particle Partitionig of Particulate Pah and Elements In The Case of The La Defense Road Tunnel Near Paris

    NASA Astrophysics Data System (ADS)

    Quisefit, J.-P.; Garivait, S.; Schwell, M.; Goriaux, M.; Steiner, E.

    The aim of this study is to characterise, in real circulation conditions, the physico- chemistry of the French automotive emissions. Pollutants measured in a road tunnel are not photochemically processed and thus do represent the original emission at its source. Furthermore, the wide distribution of car types encountered in real circula- tion conditions assures representativety of the actual (French) car park. The French automotive emissions are also of particular interest because the proportion of Diesel engines is bigger than in other countries. Particles were sampled in the La Défense Road tunnel using a Dekati 13 stage cascade impactor as well as a total collector with PM10 head. A biphasic collector was used to study the gas/particle partitioning of the PAHs. The concentration of 14 PAHs was determined in each size fraction by using microwave extraction followed by HPLC in connection with a fluorimeter. Par- ticulate concentration of elements (Al,S,Ca,Cl,Pd,Pt,Ce,Rh...) were determined using X-Ray fluorescence. Environmental conditions, such as temperature, pressure, rela- tive humidity, wind speed as well as CO and NOx levels were monitored continuously during the campaign. The results show clearly that light PAHs, such as phenanthrene, acenaphtene or fluorene exhibit a bimodal distribution. They are adsorbed on fine par- ticles (maximum at about 200 nm) as well as on coarse particles (maximum at about 4 micron). In contrast, heavier PAHs, like Benz(a)pyrene or Benzofluoranthene, are found only on fine particles. Due to its elevated vapour pressure, naphtalene is not observed at all in the particulate phase. These results will be discussed in terms of the thermodynamic properties of the compounds and are compared to similar campaigns in other countries.

  1. Automation of the in vitro micronucleus and chromosome aberration assay for the assessment of the genotoxicity of the particulate and gas-vapor phase of cigarette smoke.

    PubMed

    Roemer, Ewald; Zenzen, Volker; Conroy, Lynda L; Luedemann, Kathrin; Dempsey, Ruth; Schunck, Christian; Sticken, Edgar Trelles

    2015-01-01

    Total particulate matter (TPM) and the gas-vapor phase (GVP) of mainstream smoke from the Reference Cigarette 3R4F were assayed in the cytokinesis-block in vitro micronucleus (MN) assay and the in vitro chromosome aberration (CA) assay, both using V79-4 Chinese hamster lung fibroblasts exposed for up to 24 h. The Metafer image analysis platform was adapted resulting in a fully automated evaluation system of the MN assay for the detection, identification and reporting of cells with micronuclei together with the determination of the cytokinesis-block proliferation index (CBPI) to quantify the treatment-related cytotoxicity. In the CA assay, the same platform was used to identify, map and retrieve metaphases for a subsequent CA evaluation by a trained evaluator. In both the assays, TPM and GVP provoked a significant genotoxic effect: up to 6-fold more micronucleated target cells than in the negative control and up to 10-fold increases in aberrant metaphases. Data variability was lower in the automated version of the MN assay than in the non-automated. It can be estimated that two test substances that differ in their genotoxicity by approximately 30% can statistically be distinguished in the automated MN and CA assays. Time savings, based on man hours, due to the automation were approximately 70% in the MN and 25% in the CA assays. The turn-around time of the evaluation phase could be shortened by 35 and 50%, respectively. Although only cigarette smoke-derived test material has been applied, the technical improvements should be of value for other test substances.

  2. Crystalline-state guest-exchange and gas-adsorption phenomenon for a "soft" supramolecular porous framework stacking by a rigid linear coordination polymer.

    PubMed

    Hu, Sheng; He, Kun-Huan; Zeng, Ming-Hua; Zou, Hua-Hong; Jiang, Yi-Min

    2008-06-16

    A 1D rigid, linear coordination polymer, (4,4'-bipyridine)(2-pyridylsulfonate)copper, has been applied for the controlled-assembly of a new porous host that generates 1D channels by an interdigitated packing through the recognition of hydrogen bonding and pi-pi stacking interactions. The porous structure is architecturally robust when it reversibly uptakes water molecules and exchanges guest small molecules (MeOH, i-PrOH) from solution as determined by single-crystal-to-single-crystal transformation studies. Moreover, the open-channel solid displays irreversible benzene and toluene vapor sorption behaviors attributed to a widening of the channel cross-section that fetters the larger guest molecules, resulting from the dynamic, "soft" supramolecular framework.

  3. Short protection device for stack of electrolytic cells

    DOEpatents

    Katz, Murray; Schroll, Craig R.

    1985-10-22

    Electrical short protection is provided in an electrolytic cell stack by the combination of a thin, nonporous ceramic shield and a noble metal foil disposed on opposite sides of the sealing medium in a gas manifold gasket. The thin ceramic shield, such as alumina, is placed between the porous gasket and the cell stack face at the margins of the negative end plate to the most negative cells to impede ion current flow. The noble metal foil, for instance gold, is electrically coupled to the negative potential of the stack to collect positive ions at a harmless location away from the stack face. Consequently, corrosion products from the stack structure deposit on the foil rather than on the stack face to eliminate electrical shorting of cells at the negative end of the stack.

  4. Inorganic hazardous air pollutants before and after a limestone flue gas desulfurization system as a function of <10 micrometer particle sizes and unit load

    SciTech Connect

    Maxwell, D.P.; Williams, W.A.; Flora, H.B. II

    1995-12-31

    Radian Corporation collected size-fractionated particulate samples from stack gas at a unit burning high sulfur coal with a venturi scrubber FGD system. Independent sample fractions were collected under high-load and low-load operating conditions and subjected to various techniques designed to measure the total composition and surface-extractable concentrations of selected trace elements. The relationships between unit load, particle-size distribution, total composition, and surface-extractable inorganic species are reported and compared to show the availability of trace elements relevant to potential health risks from flue gas particulate emissions.

  5. Investigation of time-resolved atmospheric conditions and indoor/outdoor particulate matter concentrations in homes with gas and biomass cook stoves in Nogales, Sonora, Mexico.

    PubMed

    Holmes, Heather A; Pardyjak, Eric R

    2014-07-01

    This paper reports findings from a case study designed to investigate indoor and outdoor air quality in homes near the United States-Mexico border During the field study, size-resolved continuous particulate matter (PM) concentrations were measured in six homes, while outdoor PM was simultaneously monitored at the same location in Nogales, Sonora, Mexico, during March 14-30, 2009. The purpose of the experiment was to compare PM in homes using different fuels for cooking, gas versus biomass, and to obtain a spatial distribution of outdoor PM in a region where local sources vary significantly (e.g., highway, border crossing, unpaved roads, industry). Continuous PM data were collected every 6 seconds using a valve switching system to sample indoor and outdoor air at each home location. This paper presents the indoor PM data from each home, including the relationship between indoor and outdoor PM. The meteorological conditions associated with elevated ambient PM events in the region are also discussed. Results indicate that indoor air pollution has a strong dependence on cooking fuel, with gas stoves having hourly averaged median PM3 concentrations in the range of 134 to 157 microg m(-3) and biomass stoves 163 to 504 microg m(-1). Outdoor PM also indicates a large spatial heterogeneity due to the presence of microscale sources and meteorological influences (median PM3: 130 to 770 microg m(-3)). The former is evident in the median and range of daytime PM values (median PM3: 250 microg m(-3), maximum: 9411 microg m(-3)), while the meteorological influences appear to be dominant during nighttime periods (median PM3: 251 microg m(-3), maximum: 10,846 microg m(-3)). The atmospheric stability is quantified for three nighttime temperature inversion episodes, which were associated with an order of magnitude increase in PM10 at the regulatory monitor in Nogales, AZ (maximum increase: 12 to 474 microg m(-3)). Implications: Regulatory air quality standards are based on outdoor

  6. Development of on-site PAFC stacks

    SciTech Connect

    Hotta, K.; Matsumoto, Y.; Horiuchi, H.; Ohtani, T.

    1996-12-31

    PAFC (Phosphoric Acid Fuel Cell) has been researched for commercial use and demonstration plants have been installed in various sites. However, PAFC don`t have a enough stability yet, so more research and development must be required in the future. Especially, cell stack needs a proper state of three phases (liquid, gas and solid) interface. It is very difficult technology to keep this condition for a long time. In the small size cell with the electrode area of 100 cm{sup 2}, gas flow and temperature distributions show uniformity. But in the large size cell with the electrode area of 4000 cm{sup 2}, the temperature distributions show non-uniformity. These distributions would cause to be shorten the cell life. Because these distributions make hot-spot and gas poverty in limited parts. So we inserted thermocouples in short-stack for measuring three-dimensional temperature distributions and observed effects of current density and gas utilization on temperature.

  7. PAM stack test utility

    SciTech Connect

    Grondona, Mark A.

    2007-08-22

    The pamtest utility calls the normal PAM hooks using a service and username supplied on the command line. This allows an administratory to test any one of many configured PAM stacks as any existing user on the machine.

  8. Stacked Buoyant Payload Launcher

    DTIC Science & Technology

    2013-05-14

    reserved for undersea launched missiles. Underwater deployment of smaller payloads has been limited to ejection from torpedo tubes, the trash disposal...COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE Stacked Buoyant Payload Launcher 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM...1 of 11 STACKED BUOYANT PAYLOAD LAUNCHER STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured and

  9. Radiation Measurements Laboratory (RML) calibration and assessment of the ATR SPING-3 stack effluent monitor

    SciTech Connect

    Koeppen, L.D.; Rogers, J.W.; Simpson, O.D.

    1983-12-01

    An evaluation, calibration and assessment of the Eberline SPING-3 ATR stack effluent monitor was conducted. This unit which monitors particulate, iodine and noble gas effluents was producing abnormal results following the initial installation and operational testing. The purposes of this work were to find the causes of the abnormal results and correct them if possible; check the calibrations and adjust them if necessary; and to provide a better in-depth understanding of what the unit is monitoring and how well it performs under this application. Results have shown that there were some problems associated with the unit as initially installed and tested. These problems have been identified and suggested alternatives shown, the monitor was found to be applicable to some extent under the current conditions. The calibrations have been checked and adjustments made. More operation testing and evaluation is needed to assess how well this works under a variety of ATR operating conditions. 2 references, 10 figures, 3 tables. (ACR)

  10. 76. General view looking east showing Rust Co. boiler stacks ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    76. General view looking east showing Rust Co. boiler stacks at left, Babcock & Wilcox type boiler stacks at right, Dovel horizontal gas washer in foreground, and No. 1 Furnace in distance. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  11. Anisotropic electronic conduction in stacked two-dimensional titanium carbide

    PubMed Central

    Hu, Tao; Zhang, Hui; Wang, Jiemin; Li, Zhaojin; Hu, Minmin; Tan, Jun; Hou, Pengxiang; Li, Feng; Wang, Xiaohui

    2015-01-01

    Stacked two-dimensional titanium carbide is an emerging conductive material for electrochemical energy storage which requires an understanding of the intrinsic electronic conduction. Here we report the electronic conduction properties of stacked Ti3C2T2 (T = OH, O, F) with two distinct stacking sequences (Bernal and simple hexagonal). On the basis of first-principles calculations and energy band theory analysis, both stacking sequences give rise to metallic conduction with Ti 3d electrons contributing most to the conduction. The conduction is also significantly anisotropic due to the fact that the effective masses of carriers including electrons and holes are remarkably direction-dependent. Such an anisotropic electronic conduction is evidenced by the I−V curves of an individual Ti3C2T2 particulate, which demonstrates that the in-plane electrical conduction is at least one order of magnitude higher than that vertical to the basal plane. PMID:26548439

  12. Anisotropic electronic conduction in stacked two-dimensional titanium carbide

    NASA Astrophysics Data System (ADS)

    Hu, Tao; Zhang, Hui; Wang, Jiemin; Li, Zhaojin; Hu, Minmin; Tan, Jun; Hou, Pengxiang; Li, Feng; Wang, Xiaohui

    2015-11-01

    Stacked two-dimensional titanium carbide is an emerging conductive material for electrochemical energy storage which requires an understanding of the intrinsic electronic conduction. Here we report the electronic conduction properties of stacked Ti3C2T2 (T = OH, O, F) with two distinct stacking sequences (Bernal and simple hexagonal). On the basis of first-principles calculations and energy band theory analysis, both stacking sequences give rise to metallic conduction with Ti 3d electrons contributing most to the conduction. The conduction is also significantly anisotropic due to the fact that the effective masses of carriers including electrons and holes are remarkably direction-dependent. Such an anisotropic electronic conduction is evidenced by the I-V curves of an individual Ti3C2T2 particulate, which demonstrates that the in-plane electrical conduction is at least one order of magnitude higher than that vertical to the basal plane.

  13. Anisotropic electronic conduction in stacked two-dimensional titanium carbide.

    PubMed

    Hu, Tao; Zhang, Hui; Wang, Jiemin; Li, Zhaojin; Hu, Minmin; Tan, Jun; Hou, Pengxiang; Li, Feng; Wang, Xiaohui

    2015-11-09

    Stacked two-dimensional titanium carbide is an emerging conductive material for electrochemical energy storage which requires an understanding of the intrinsic electronic conduction. Here we report the electronic conduction properties of stacked Ti3C2T2 (T = OH, O, F) with two distinct stacking sequences (Bernal and simple hexagonal). On the basis of first-principles calculations and energy band theory analysis, both stacking sequences give rise to metallic conduction with Ti 3d electrons contributing most to the conduction. The conduction is also significantly anisotropic due to the fact that the effective masses of carriers including electrons and holes are remarkably direction-dependent. Such an anisotropic electronic conduction is evidenced by the I-V curves of an individual Ti3C2T2 particulate, which demonstrates that the in-plane electrical conduction is at least one order of magnitude higher than that vertical to the basal plane.

  14. 40 CFR 86.110-94 - Exhaust gas sampling system; diesel-cycle vehicles, and Otto-cycle vehicles requiring particulate...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., continuous HFID (required for petroleum-fueled diesel-cycle and optional for methanol-fueled, natural gas... gas dilution function at the vehicle tailpipe exit. (6) For natural gas-fueled and liquefied petroleum...—petroleum-fueled, natural gas-fueled and liquefied petroleum gas-fueled vehicles. The components...

  15. 40 CFR 86.110-94 - Exhaust gas sampling system; diesel-cycle vehicles, and Otto-cycle vehicles requiring particulate...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... heated flame ionization detector (HFID) (375 °±20 °F (191 °±11 °C)) sample for total hydrocarbon (THC... probes (i.e., the particulate probe and the heated THC sample probe). It is recommended that uniform...) Sufficiently distant (radially) from the THC probe (when the THC probe is required) so as to be free from...

  16. Stack filter classifiers

    SciTech Connect

    Porter, Reid B; Hush, Don

    2009-01-01

    Just as linear models generalize the sample mean and weighted average, weighted order statistic models generalize the sample median and weighted median. This analogy can be continued informally to generalized additive modeels in the case of the mean, and Stack Filters in the case of the median. Both of these model classes have been extensively studied for signal and image processing but it is surprising to find that for pattern classification, their treatment has been significantly one sided. Generalized additive models are now a major tool in pattern classification and many different learning algorithms have been developed to fit model parameters to finite data. However Stack Filters remain largely confined to signal and image processing and learning algorithms for classification are yet to be seen. This paper is a step towards Stack Filter Classifiers and it shows that the approach is interesting from both a theoretical and a practical perspective.

  17. Stacked antiaromatic porphyrins

    PubMed Central

    Nozawa, Ryo; Tanaka, Hiroko; Cha, Won-Young; Hong, Yongseok; Hisaki, Ichiro; Shimizu, Soji; Shin, Ji-Young; Kowalczyk, Tim; Irle, Stephan; Kim, Dongho; Shinokubo, Hiroshi

    2016-01-01

    Aromaticity is a key concept in organic chemistry. Even though this concept has already been theoretically extrapolated to three dimensions, it usually still remains restricted to planar molecules in organic chemistry textbooks. Stacking of antiaromatic π-systems has been proposed to induce three-dimensional aromaticity as a result of strong frontier orbital interactions. However, experimental evidence to support this prediction still remains elusive so far. Here we report that close stacking of antiaromatic porphyrins diminishes their inherent antiaromaticity in the solid state as well as in solution. The antiaromatic stacking furthermore allows a delocalization of the π-electrons, which enhances the two-photon absorption cross-section values of the antiaromatic porphyrins. This feature enables the dynamic switching of the non-linear optical properties by controlling the arrangement of antiaromatic π-systems on the basis of intermolecular orbital interactions. PMID:27901014

  18. Stacked antiaromatic porphyrins

    NASA Astrophysics Data System (ADS)

    Nozawa, Ryo; Tanaka, Hiroko; Cha, Won-Young; Hong, Yongseok; Hisaki, Ichiro; Shimizu, Soji; Shin, Ji-Young; Kowalczyk, Tim; Irle, Stephan; Kim, Dongho; Shinokubo, Hiroshi

    2016-11-01

    Aromaticity is a key concept in organic chemistry. Even though this concept has already been theoretically extrapolated to three dimensions, it usually still remains restricted to planar molecules in organic chemistry textbooks. Stacking of antiaromatic π-systems has been proposed to induce three-dimensional aromaticity as a result of strong frontier orbital interactions. However, experimental evidence to support this prediction still remains elusive so far. Here we report that close stacking of antiaromatic porphyrins diminishes their inherent antiaromaticity in the solid state as well as in solution. The antiaromatic stacking furthermore allows a delocalization of the π-electrons, which enhances the two-photon absorption cross-section values of the antiaromatic porphyrins. This feature enables the dynamic switching of the non-linear optical properties by controlling the arrangement of antiaromatic π-systems on the basis of intermolecular orbital interactions.

  19. 40 CFR Table 4 to Subpart Jjjjjj... - Performance (Stack) Testing Requirements

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 19.10-1981. a d. Measure the moisture content of the stack gas Method 4 in appendix A-3 to part 60 of... 19.10-1981. a d. Measure the moisture content of the stack gas Method 4 in appendix A-3 to part 60 of... moisture content of the stack gas Method 4 in appendix A-3 to part 60 of this chapter. d. Measure...

  20. Laser pulse stacking method

    DOEpatents

    Moses, Edward I.

    1992-01-01

    A laser pulse stacking method is disclosed. A problem with the prior art has been the generation of a series of laser beam pulses where the outer and inner regions of the beams are generated so as to form radially non-synchronous pulses. Such pulses thus have a non-uniform cross-sectional area with respect to the outer and inner edges of the pulses. The present invention provides a solution by combining the temporally non-uniform pulses in a stacking effect to thus provide a more uniform temporal synchronism over the beam diameter.

  1. Laser pulse stacking method

    DOEpatents

    Moses, E.I.

    1992-12-01

    A laser pulse stacking method is disclosed. A problem with the prior art has been the generation of a series of laser beam pulses where the outer and inner regions of the beams are generated so as to form radially non-synchronous pulses. Such pulses thus have a non-uniform cross-sectional area with respect to the outer and inner edges of the pulses. The present invention provides a solution by combining the temporally non-uniform pulses in a stacking effect to thus provide a more uniform temporal synchronism over the beam diameter. 2 figs.

  2. Gene stacking by recombinases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Efficient methods of stacking genes into plant genomes are needed to expedite transfer of multigenic traits into diverse crops grown in a variety of environments. Over two decades of research has identified several site-specific recombinases that carry out efficient cis and trans recombination betw...

  3. Stacked Sequential Learning

    DTIC Science & Technology

    2005-07-01

    a constant factor of K + 2. (To see this, note sequential stacking requires training K+2 classifiers: the classifiers f1, . . . , fK used in cross...on the non- sequential learners (ME and VP) but improves per- formance of the sequential learners (CRFs and VPH - MMs) less consistently. This pattern

  4. Performance evaluation of PEFC stack

    SciTech Connect

    Fujita, Jun-ichi; Ohtsuki, Jitsuji; Shindo, Yoshihiko

    1996-12-31

    Polymer electrolyte fuel cells (PEFCs) have many advantages such as high current density, short start-up time and endurance for start-stop cycles. Making use of these advantages, Fuji Electric has been working with the Kansai Electric Power Co., Inc. to explore practical applications of PEFCs for an electric utility use. Since large-sized electrodes are required in the electric utility applications, we have fabricated 600cm{sup 2} membrane-electrode assemblies by using hot-press method. We have also designed a cell structure to realize a uniform reaction over the electrodes. The structure includes a properly-shaped gas flow channel, a temperature-gradient cooling system. Using the 600cm{sup 2} (25x24cm) electrodes, a 30-cell stack (5kW) were constructed and tested.

  5. Particle size distribution characteristics of cotton gin first stage lint cleaning system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  6. Combined mote system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or e...

  7. Master trash system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or ...

  8. Particle size distribution characteristics of cotton gin combined mote system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  9. Overflow system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than...

  10. First stage lint cleaning system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006, Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or equal...

  11. Particle size distribution characteristics of cotton gin unloading system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  12. Particle size distribution characteristics of cotton gin second stage mote system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  13. Particle size distribution characteristics of cotton gin second stage lint cleaning system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  14. Combined lint cleaning system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or e...

  15. Particle size distribution characteristics of cotton gin mote trash system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  16. Second stage mote system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or equal...

  17. Second stage lint cleaning system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or equal...

  18. Mote cleaner system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or ...

  19. Mote trash system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than...

  20. Particle size distribution characteristics of cotton gin combined lint cleaning system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  1. Mote cyclone robber system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than...

  2. Particle size distribution characteristics of cotton gin overflow system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  3. Cyclone robber system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or ...

  4. Particle size distribution characteristics of cotton gin master trash system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  5. First stage mote system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or e...

  6. Particle size distribution characteristics of cotton gin mote cleaner system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  7. Unloading system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than...

  8. Particle size distribution characteristics of cotton gin first stage mote system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  9. Battery condenser system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or e...

  10. Particle size distribution characteristics of cotton gin battery condenser system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  11. Particle size distribution characteristics of cotton gin mote cyclone robber system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  12. Particle size distribution characteristics of cotton gin cyclone robber system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  13. Description of the Process Model for the Technoeconomic Evaluation of MEA versus Mixed Amines for Carbon Dioxide Removal from Stack Gas

    SciTech Connect

    Jones, Dale A.

    2013-11-08

    This model description is supplemental to the Lawrence Livermore National Laboratory (LLNL) report LLNL-TR-642494, Technoeconomic Evaluation of MEA versus Mixed Amines for CO2 Removal at Near- Commercial Scale at Duke Energy Gibson 3 Plant. We describe the assumptions and methodology used in the Laboratory’s simulation of its understanding of Huaneng’s novel amine solvent for CO2 capture with 35% mixed amine. The results of that simulation have been described in LLNL-TR-642494. The simulation was performed using ASPEN 7.0. The composition of the Huaneng’s novel amine solvent was estimated based on information gleaned from Huaneng patents. The chemistry of the process was described using nine equations, representing reactions within the absorber and stripper columns using the ELECTNRTL property method. As a rate-based ASPEN simulation model was not available to Lawrence Livermore at the time of writing, the height of a theoretical plate was estimated using open literature for similar processes. Composition of the flue gas was estimated based on information supplied by Duke Energy for Unit 3 of the Gibson plant. The simulation was scaled at one million short tons of CO2 absorbed per year. To aid stability of the model, convergence of the main solvent recycle loop was implemented manually, as described in the Blocks section below. Automatic convergence of this loop led to instability during the model iterations. Manual convergence of the loop enabled accurate representation and maintenance of model stability.

  14. Thermoacoustics with idealized heat exchangers and no stack.

    PubMed

    Wakeland, Ray Scott; Keolian, Robert M

    2002-06-01

    A model is developed for thermoacoustic devices that have neither stack nor regenerator. These "no-stack" devices have heat exchangers placed close together in an acoustic standing wave of sufficient amplitude to allow individual parcels of gas to enter both exchangers. The assumption of perfect heat transfer in the exchangers facilitates the construction of a simple model similar to the "moving parcel picture" that is used as a first approach to stack-based engines and refrigerators. The model no-stack cycle is shown to have potentially greater inviscid efficiency than a comparable stack model. However, losses from flow through the heat exchangers and on the walls of the enclosure are greater than those in a stack-based device due to the increased acoustic pressure amplitude. Estimates of these losses in refrigerators are used to compare the possible efficiencies of real refrigerators made with or without a stack. The model predicts that no-stack refrigerators can exceed stack-based refrigerators in efficiency, but only for particular enclosure geometries.

  15. Combustor for fine particulate coal

    DOEpatents

    Carlson, L.W.

    1988-01-26

    A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover. 4 figs.

  16. Combustor for fine particulate coal

    DOEpatents

    Carlson, L.W.

    1988-11-08

    A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover. 4 figs.

  17. Combustor for fine particulate coal

    DOEpatents

    Carlson, Larry W.

    1988-01-01

    A particulate coal combustor with two combustion chambers is provided. The first combustion chamber is toroidal; air and fuel are injected, mixed, circulated and partially combusted. The air to fuel ratio is controlled to avoid production of soot or nitrogen oxides. The mixture is then moved to a second combustion chamber by injection of additional air where combustion is completed and ash removed. Temperature in the second chamber is controlled by cooling and gas mixing. The clean stream of hot gas is then delivered to a prime mover.

  18. Energy Expenditure of Sport Stacking

    ERIC Educational Resources Information Center

    Murray, Steven R.; Udermann, Brian E.; Reineke, David M.; Battista, Rebecca A.

    2009-01-01

    Sport stacking is an activity taught in many physical education programs. The activity, although very popular, has been studied minimally, and the energy expenditure for sport stacking is unknown. Therefore, the purposes of this study were to determine the energy expenditure of sport stacking in elementary school children and to compare that value…

  19. Iridium Interfacial Stack (IRIS)

    NASA Technical Reports Server (NTRS)

    Spry, David James (Inventor)

    2015-01-01

    An iridium interfacial stack ("IrIS") and a method for producing the same are provided. The IrIS may include ordered layers of TaSi.sub.2, platinum, iridium, and platinum, and may be placed on top of a titanium layer and a silicon carbide layer. The IrIS may prevent, reduce, or mitigate against diffusion of elements such as oxygen, platinum, and gold through at least some of its layers.

  20. Fuel Cell Stacks

    DTIC Science & Technology

    1975-04-01

    AD-A009 587 FUEL CELL STACKS Bernard S. Baker Energy Research Corporation Prepared for: Army Mobility Equipment Research and Development Center April... Mobility Equipment Research and Development Center Unclassified For- Belvoir, Virginia 22060 [15. DE.CLASSIFICATION/L.TWNOGRADING SCREOUJLE 16...the majority of effort has been directed at translating technoilogy for small comn- ponent manufacture on a laboratory scale into large size components

  1. 30 CFR 250.441 - What are the requirements for a surface BOP stack?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.441 What are the requirements for a surface BOP stack? (a) When you drill with a surface BOP stack, you must install the...

  2. 30 CFR 250.441 - What are the requirements for a surface BOP stack?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.441 What are the requirements for a surface BOP stack? (a) When you drill with a surface BOP stack, you must install the...

  3. 30 CFR 250.441 - What are the requirements for a surface BOP stack?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.441 What are the requirements for a surface BOP stack? (a) When you drill with a surface BOP stack, you must install the...

  4. 40 CFR Table 4 to Subpart Jjjjjj... - Performance (Stack) Testing Requirements

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... Determine velocity and volumetric flow-rate of the stack gas Method 2, 2F, or 2G in appendix A-2 to part 60.... Determine velocity and volumetric flow-rate of the stack gas Method 2, 2F, or 2G in appendix A-2 to part...

  5. Development of internal reforming carbonate fuel cell stack technology

    SciTech Connect

    Farooque, M.

    1990-10-01

    Activities under this contract focused on the development of a coal-fueled carbonate fuel cell system design and the stack technology consistent with the system design. The overall contract effort was divided into three phases. The first phase, completed in January 1988, provided carbonate fuel cell component scale-up from the 1ft{sup 2} size to the commercial 4ft{sup 2} size. The second phase of the program provided the coal-fueled carbonate fuel cell system (CGCFC) conceptual design and carried out initial research and development needs of the CGCFC system. The final phase of the program emphasized stack height scale-up and improvement of stack life. The results of the second and third phases are included in this report. Program activities under Phase 2 and 3 were designed to address several key development areas to prepare the carbonate fuel cell system, particularly the coal-fueled CFC power plant, for commercialization in late 1990's. The issues addressed include: Coal-Gas Related Considerations; Cell and Stack Technology Improvement; Carbonate Fuel Cell Stack Design Development; Stack Tests for Design Verification; Full-Size Stack Design; Test Facility Development; Carbonate Fuel Cell Stack Cost Assessment; and Coal-Fueled Carbonate Fuel Cell System Design. All the major program objectives in each of the topical areas were successfully achieved. This report is organized along the above-mentioned topical areas. Each topical area has been processed separately for inclusion on the data base.

  6. When is stacking confusing? The impact of confusion on stacking in deep H I galaxy surveys

    NASA Astrophysics Data System (ADS)

    Jones, Michael G.; Haynes, Martha P.; Giovanelli, Riccardo; Papastergis, Emmanouil

    2016-01-01

    We present an analytic model to predict the H I mass contributed by confused sources to a stacked spectrum in a generic H I survey. Based on the ALFALFA (Arecibo Legacy Fast ALFA) correlation function, this model is in agreement with the estimates of confusion present in stacked Parkes telescope data, and was used to predict how confusion will limit stacking in the deepest Square Kilometre Array precursor H I surveys. Stacking with LADUMA (Looking At the Distant Universe with MeerKAT) and DINGO UDEEP (Deep Investigation of Neutral Gas Origins - Ultra Deep) data will only be mildly impacted by confusion if their target synthesized beam size of 10 arcsec can be achieved. Any beam size significantly above this will result in stacks that contain a mass in confused sources that is comparable to (or greater than) that which is detectable via stacking, at all redshifts. CHILES (COSMOS H I Large Extragalactic Survey) 5 arcsec resolution is more than adequate to prevent confusion influencing stacking of its data, throughout its bandpass range. FAST (Five hundred metre Aperture Spherical Telescope) will be the most impeded by confusion, with H I surveys likely becoming heavily confused much beyond z = 0.1. The largest uncertainties in our model are the redshift evolution of the H I density of the Universe and the H I correlation function. However, we argue that the two idealized cases we adopt should bracket the true evolution, and the qualitative conclusions are unchanged regardless of the model choice. The profile shape of the signal due to confusion (in the absence of any detection) was also modelled, revealing that it can take the form of a double Gaussian with a narrow and wide component.

  7. Progress report and technology status development of an EG and G Berthold LB-150 alpha/beta particulate monitor for use on the East Tennessee Technology Park Toxic Substances Control Act Incinerator

    SciTech Connect

    Shor, J.T.; Singh, S.P.N.; Gibson, L.V. Jr.

    1998-06-01

    The purpose of this project was to modify and evaluate a commercially available EG and G Berthold LB-150 alpha-beta radionuclide particulate monitor for the high-temperature and moisture-saturation conditions of the East Tennessee Technology Park (formerly K-25 Site) Toxic Substances Control Act (TSCA) Incinerator stack. The monitor was originally outfitted for operation at gas temperatures of 150 F on the defunct Los Alamos National Laboratory (LANL) controlled air incinerator, and the objective was to widen its operating envelope. A laboratory apparatus was constructed that simulated the effects of water-saturated air at the TSCA Incinerator stack-gas temperatures, 183 F. An instrumented set of heat exchangers was constructed to then condition the gas so that the radionuclide monitor could be operated without condensation. Data were collected under the conditions of the elevated temperatures and humidities and are reported herein, and design considerations of the apparatus are provided. The heat exchangers and humidification equipment performed as designed, the Mylar film held, and the instrument suffered no ill effects. However, for reasons as yet undetermined, the sensitivity of the radionuclide detection diminishes as the gas temperature is elevated, whether the gas is humidified or not. The manufacturer has had no experience with (a) the operation of the monitor under these conditions and (b) any commercial market that might exist for an instrument that operates under these conditions. The monitor was not installed into the radiologically contaminated environment of the TSCA Incinerator stack pending resolution of this technical issue.

  8. Stacked Extreme Learning Machines.

    PubMed

    Zhou, Hongming; Huang, Guang-Bin; Lin, Zhiping; Wang, Han; Soh, Yeng Chai

    2015-09-01

    Extreme learning machine (ELM) has recently attracted many researchers' interest due to its very fast learning speed, good generalization ability, and ease of implementation. It provides a unified solution that can be used directly to solve regression, binary, and multiclass classification problems. In this paper, we propose a stacked ELMs (S-ELMs) that is specially designed for solving large and complex data problems. The S-ELMs divides a single large ELM network into multiple stacked small ELMs which are serially connected. The S-ELMs can approximate a very large ELM network with small memory requirement. To further improve the testing accuracy on big data problems, the ELM autoencoder can be implemented during each iteration of the S-ELMs algorithm. The simulation results show that the S-ELMs even with random hidden nodes can achieve similar testing accuracy to support vector machine (SVM) while having low memory requirements. With the help of ELM autoencoder, the S-ELMs can achieve much better testing accuracy than SVM and slightly better accuracy than deep belief network (DBN) with much faster training speed.

  9. Measurement of heat conduction through stacked screens.

    PubMed

    Lewis, M A; Kuriyama, T; Kuriyama, F; Radebaugh, R

    1998-01-01

    This paper describes the experimental apparatus for the measurement of heat conduction through stacked screens as well as some experimental results taken with the apparatus. Screens are stacked in a fiberglass-epoxy cylinder, which is 24.4 mm in diameter and 55 mm in length. The cold end of the stacked screens is cooled by a Gifford-McMahon (GM) cryocooler at cryogenic temperature, and the hot end is maintained at room temperature. Heat conduction through the screens is determined from the temperature gradient in a calibrated heat flow sensor mounted between the cold end of the stacked screens and the GM cryocooler. The samples used for these experiments consisted of 400-mesh stainless steel screens, 400-mesh phosphor bronze screens, and two different porosities of 325-mesh stainless steel screens. The wire diameter of the 400-mesh stainless steel and phosphor bronze screens was 25.4 micrometers and the 325-mesh stainless steel screen wire diameters were 22.9 micrometers and 27.9 micrometers. Standard porosity values were used for the experimental data with additional porosity values used on selected experiments. The experimental results showed that the helium gas between each screen enhanced the heat conduction through the stacked screens by several orders of magnitude compared to that in vacuum. The conduction degradation factor is the ratio of actual heat conduction to the heat conduction where the regenerator material is assumed to be a solid rod of the same cross sectional area as the metal fraction of the screen. This factor was about 0.1 for the stainless steel and 0.022 for the phosphor bronze, and almost constant for the temperature range of 40 to 80 K at the cold end.

  10. Measurement of heat conduction through stacked screens

    NASA Technical Reports Server (NTRS)

    Lewis, M. A.; Kuriyama, T.; Kuriyama, F.; Radebaugh, R.

    1998-01-01

    This paper describes the experimental apparatus for the measurement of heat conduction through stacked screens as well as some experimental results taken with the apparatus. Screens are stacked in a fiberglass-epoxy cylinder, which is 24.4 mm in diameter and 55 mm in length. The cold end of the stacked screens is cooled by a Gifford-McMahon (GM) cryocooler at cryogenic temperature, and the hot end is maintained at room temperature. Heat conduction through the screens is determined from the temperature gradient in a calibrated heat flow sensor mounted between the cold end of the stacked screens and the GM cryocooler. The samples used for these experiments consisted of 400-mesh stainless steel screens, 400-mesh phosphor bronze screens, and two different porosities of 325-mesh stainless steel screens. The wire diameter of the 400-mesh stainless steel and phosphor bronze screens was 25.4 micrometers and the 325-mesh stainless steel screen wire diameters were 22.9 micrometers and 27.9 micrometers. Standard porosity values were used for the experimental data with additional porosity values used on selected experiments. The experimental results showed that the helium gas between each screen enhanced the heat conduction through the stacked screens by several orders of magnitude compared to that in vacuum. The conduction degradation factor is the ratio of actual heat conduction to the heat conduction where the regenerator material is assumed to be a solid rod of the same cross sectional area as the metal fraction of the screen. This factor was about 0.1 for the stainless steel and 0.022 for the phosphor bronze, and almost constant for the temperature range of 40 to 80 K at the cold end.

  11. SOFC cells and stacks for complex fuels

    SciTech Connect

    Edward M. Sabolsky; Matthew Seabaugh; Katarzyna Sabolsky; Sergio A. Ibanez; Zhimin Zhong

    2007-07-01

    Reformed hydrocarbon and coal (syngas) fuels present an opportunity to integrate solid oxide fuel cells into the existing fuel infrastructure. However, these fuels often contain impurities or additives that may lead to cell degradation through sulfur poisoning or coking. Achieving high performance and sulfur tolerance in SOFCs operating on these fuels would simplify system balance of plant and sequestration of anode tail gas. NexTech Materials, Ltd., has developed a suite of materials and components (cells, seals, interconnects) designed for operation in sulfur-containing syngas fuels. These materials and component technologies have been integrated into an SOFC stack for testing on simulated propane, logistic fuel reformates and coal syngas. Details of the technical approach, cell and stack performance is reported.

  12. IAS Stacking Library in IDL

    NASA Astrophysics Data System (ADS)

    Bavouzet, Nicolas; Beelen, Alexandre; Bethermin, Matthieu; Dole, Herve; Ponthieu, Nicolas

    2013-02-01

    This IDL library is designed to be used on astronomical images. Its main aim is to stack data to allow a statistical detection of faint signal, using a prior. For instance, you can stack 160um data using the positions of galaxies detected at 24um or 3.6um, or use WMAP sources to stack Planck data. It can estimate error bars using bootstrap, and it can perform photometry (aperture photometry, or PSF fitting, or other that you can plug). The IAS Stacking Library works with gnomonic projections (RA---TAN), and also with HEALPIX projection.

  13. Stacked insulator induction accelerator gaps

    SciTech Connect

    Houck, T.I.; Westenskow, G.A.; Kim, J.S.; Eylon, S.; Henestroza, E.; Yu, S.S.; Vanecek, D.

    1997-05-01

    Stacked insulators, with alternating layers of insulating material and conducting film, have been shown to support high surface electrical field stresses. We have investigated the application of the stacked insulator technology to the design of induction accelerator modules for the Relativistic-Klystron Two-Beam Accelerator program. The rf properties of the accelerating gaps using stacked insulators, particularly the impedance at frequencies above the beam pipe cutoff frequency, are investigated. Low impedance is critical for Relativistic-Klystron Two-Beam Accelerator applications where a high current, bunched beam is trsnsported through many accelerating gaps. An induction accelerator module designs using a stacked insulator is presented.

  14. Stack Trace Analysis Tool

    SciTech Connect

    2013-02-19

    STAT is a light weight debugging tool that gathers and merges stack traces from all of the processes in a parallell application. STAT uses the MRNet tree based overlay network to broadcast commands from the tool front-end to the STAT daemons and for the front-end to gather the traces from the STAT daemons. As the traces propagate through the MRNet network tree, they are merged across all tasks to from a single call prefix tree. The call prefix tree can be examined to identify tasks with similar function call patterns and to delineate a small set of equivalence slasses. A representative task from each of these classes can then be fed into a full feature debugger like TotalView for root cause analysis.

  15. Diesel particulate control

    SciTech Connect

    Bertelsen, F.I. )

    1988-01-01

    Diesel particulates, because of their chemical composition and extremely small size, have raised health and welfare issues. Health experts have expressed concern that they contribute to or aggravate chronic lung diseases such as asthma, bronchitis and emphysema, and there is the lingering issue about the potential cancer risk from exposure to diesel particulate. Diesel particulates impair visibility, soil buildings, contribute to structural damage through corrosion and give off a pungent odor. Diesel trucks, buses and cars together are such a significant and growing source of particulate emissions. Such vehicles emit 30 to 70 times more particulate matter than gasoline vehicles equipped with catalytic converters. Diesel engines currently power the majority of larger trucks and buses. EPA predicted that, if left uncontrolled, diesel particulate from motor vehicles would increase significantly. Diesel particulate emissions from motor vehicles are particularly troublesome because they frequently are emitted directly into the breathing zone where we work and recreate. The U.S. Congress recognized the risks posed by diesel particulate and as part of the 1977 Clean Air Act Amendments established specific, technology-forcing requirements for controlling these emissions. The U.S. Environmental Protection Agency (EPA) in 1980 established particulate standards for automobiles and light trucks and in 1985, heavy trucks and buses. California, concerned that EPA standards would not adequately protect its citizens, adopted its own set of standards for passenger cars and light trucks. This paper discusses emerging technologies proposed to address the problem.

  16. Results of Self-Absorption Study on the Versapor 3000 Filters for Radioactive Particulate Air Sampling

    SciTech Connect

    Barnett, J. Matthew

    2008-08-22

    Since the mid-1980s the Pacific Northwest National Laboratory (PNNL) has used a value of 0.85 as a correction factor for the self absorption of activity of particulate radioactive air samples. More recently, an effort was made to evaluate the current particulate radioactive air sample filters (Versapor® 3000) used at PNNL for self absorption effects. There were two methods used in the study, 1) to compare the radioactivity concentration by direct gas-flow proportional counting of the filter to the results obtained after acid digestion of the filter and counting again by gas-flow proportional detection and 2) to evaluate sample filters by high resolution visual/infrared microscopy to determine the depth of material loading on or in the filter fiber material. Sixty samples were selected from the archive for acid digestion in the first method and about 30 samples were selected for high resolution visual/infrared microscopy. Mass loading effects were also considered. From the sample filter analysis, large error is associated with the average self absorption factor, however, when the data is compared directly one-to-one, statistically, there appears to be good correlation between the two analytical methods. The mass loading of filters evaluated was <0.2 mg cm-2 and was also compared against other published results. The microscopy analysis shows the sample material remains on the top of the filter paper and does not imbed into the filter media. Results of the microscopy evaluation lead to the conclusion that there is not a mechanism for significant self absorption. The overall conclusion is that self-absorption is not a significant factor in the analysis of filters used at PNNL for radioactive air stack sampling of radionuclide particulates and that an applied correction factor is conservative in determining overall sample activity. A new self absorption factor of 1.0 is recommended.

  17. Particle size distribution characteristics of cotton gin third stage seed-cotton cleaning system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  18. Second stage seed-cotton cleaning system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or equal...

  19. Third stage seed-cotton cleaning system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or equal...

  20. Particle size distribution characteristics of cotton gin second stage seed-cotton cleaning system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  1. Particle size distribution characteristics of cotton gin first stage seed-cotton cleaning system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  2. Particulate filtration for sorbent-based H2 storage

    NASA Astrophysics Data System (ADS)

    van Hassel, Bart A.; Karra, Jagadeswara R.

    2016-01-01

    A method was developed for sizing the particulate filter that can be used inside a sorption-based onboard hydrogen storage system for light-duty vehicles. The method is based on a trade-off between the pressure drop across the particulate filter (during the fill of the H2 storage tank or during its discharge while driving) and the effect of this pressure drop on the usable amount of H2 gas from the H2 storage system. The permeability and filtration efficiency of the particulate filters (in the absence and presence of MOF-5 particulates) was quantified in this study, with an emphasis on meeting DOE's H2 purity requirements.

  3. Zigzag stacks and m-regular linear stacks.

    PubMed

    Chen, William Y C; Guo, Qiang-Hui; Sun, Lisa H; Wang, Jian

    2014-12-01

    The contact map of a protein fold is a graph that represents the patterns of contacts in the fold. It is known that the contact map can be decomposed into stacks and queues. RNA secondary structures are special stacks in which the degree of each vertex is at most one and each arc has length of at least two. Waterman and Smith derived a formula for the number of RNA secondary structures of length n with exactly k arcs. Höner zu Siederdissen et al. developed a folding algorithm for extended RNA secondary structures in which each vertex has maximum degree two. An equation for the generating function of extended RNA secondary structures was obtained by Müller and Nebel by using a context-free grammar approach, which leads to an asymptotic formula. In this article, we consider m-regular linear stacks, where each arc has length at least m and the degree of each vertex is bounded by two. Extended RNA secondary structures are exactly 2-regular linear stacks. For any m ≥ 2, we obtain an equation for the generating function of the m-regular linear stacks. For given m, we deduce a recurrence relation and an asymptotic formula for the number of m-regular linear stacks on n vertices. To establish the equation, we use the reduction operation of Chen, Deng, and Du to transform an m-regular linear stack to an m-reduced zigzag (or alternating) stack. Then we find an equation for m-reduced zigzag stacks leading to an equation for m-regular linear stacks.

  4. 40 CFR 62.15300 - What records must I keep for stack tests?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... of this subpart: (1) Dioxins/furans. (2) Cadmium. (3) Lead. (4) Mercury. (5) Opacity. (6) Particulate... 40 Protection of Environment 9 2012-07-01 2012-07-01 false What records must I keep for stack tests? 62.15300 Section 62.15300 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  5. Face crack reduction strategy for particulate filters

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Bhatia, Garima [Bangalore, IN

    2012-01-31

    A system comprises a particulate matter (PM) filter that comprises an upstream end for receiving exhaust gas, a downstream end and at least one portion. A control module initiates combustion of PM in the PM filter using a heater and selectively adjusts oxygen levels of the exhaust gas to adjust a temperature of combustion adjacent to the at least one portion of the PM filter. A method comprises providing a particulate matter (PM) filter that comprises an upstream end for receiving exhaust gas, a downstream end and at least one portion; initiating combustion of PM in the PM filter using a heater; selectively adjusting oxygen levels of the exhaust gas to adjust a temperature of combustion adjacent to the at least one portion of the PM filter.

  6. Stacking disorder in ice I.

    PubMed

    Malkin, Tamsin L; Murray, Benjamin J; Salzmann, Christoph G; Molinero, Valeria; Pickering, Steven J; Whale, Thomas F

    2015-01-07

    Traditionally, ice I was considered to exist in two well-defined crystalline forms at ambient pressure: stable hexagonal ice (ice Ih) and metastable cubic ice (ice Ic). However, it is becoming increasingly evident that what has been called cubic ice in the past does not have a structure consistent with the cubic crystal system. Instead, it is a stacking-disordered material containing cubic sequences interlaced with hexagonal sequences, which is termed stacking-disordered ice (ice Isd). In this article, we summarise previous work on ice with stacking disorder including ice that was called cubic ice in the past. We also present new experimental data which shows that ice which crystallises after heterogeneous nucleation in water droplets containing solid inclusions also contains stacking disorder even at freezing temperatures of around -15 °C. This supports the results from molecular simulations, that the structure of ice that crystallises initially from supercooled water is always stacking-disordered and that this metastable ice can transform to the stable hexagonal phase subject to the kinetics of recrystallization. We also show that stacking disorder in ice which forms from water droplets is quantitatively distinct from ice made via other routes. The emerging picture of ice I is that of a very complex material which frequently contains stacking disorder and this stacking disorder can vary in complexity depending on the route of formation and thermal history.

  7. Particulate Air Pollution: The Particulars

    ERIC Educational Resources Information Center

    Murphy, James E.

    1973-01-01

    Describes some of the causes and consequences of particulate air pollution. Outlines the experimental procedures for measuring the amount of particulate materials that settles from the air and for observing the nature of particulate air pollution. (JR)

  8. Pitch based foam with particulate

    DOEpatents

    Klett, James W.

    2001-01-01

    A thermally conductive, pitch based foam composite having a particulate content. The particulate alters the mechanical characteristics of the foam without severely degrading the foam thermal conductivity. The composite is formed by mixing the particulate with pitch prior to foaming.

  9. 49 CFR 178.815 - Stacking test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Stacking test. 178.815 Section 178.815... Stacking test. (a) General. The stacking test must be conducted for the qualification of all IBC design types intended to be stacked. (b) Special preparation for the stacking test. (1) All IBCs...

  10. Particulate matter fugitive dusts

    SciTech Connect

    Not Available

    1988-01-01

    Topics covered in this conference include: Review of EPA's cost/benefit analysis for additional regulation of surface coal mines; Particulate monitoring on the Kilauea East Rift, Hawaii, and The MEDUSA sampling system: case histories in the measurement of particulate matter with wide spectrum analysis.

  11. Airborne particulate discriminator

    DOEpatents

    Creek, Kathryn Louise; Castro, Alonso; Gray, Perry Clayton

    2009-08-11

    A method and apparatus for rapid and accurate detection and discrimination of biological, radiological, and chemical particles in air. A suspect aerosol of the target particulates is treated with a taggant aerosol of ultrafine particulates. Coagulation of the taggant and target particles causes a change in fluorescent properties of the cloud, providing an indication of the presence of the target.

  12. Particulate and Trace Gas Emissions from Prescribed Burns in Southeastern U.S. fuel types: Summary of a 5-year Project

    SciTech Connect

    Weise, David; Johnson, Timothy J.; Reardon, James

    2015-05-01

    Prescribed burning is an accepted practice to manage biomass in the United States and throughout the world. It is a particularly important practice in pine forests throughout the world, many of which have evolved in the presence of fire [1]. A recent survey [2] of prescribed fire use reported that 2.62 x 106 ha of forest land in the southeastern U.S. (defined by the National Association of State Foresters) burned in 2011 for silvicultural purposes such as hazardous fuel reduction, wildlife habitat improvement, and forest regeneration. Earlier surveys reported 0.9 to 1.7 x 106 ha of prescribed burning in the southern U.S. [3–5] using different survey techniques. While it is not possible to determine confidence intervals on these estimates, it is clear that the use of prescribed burning has increased since the first published estimate of 1 x 106 ha we were able to locate or the recent survey captured more information. Smoke is an important consequence of prescribed burning that must be managed, [6] and a great deal of research has been performed since the 1970s trying to characterize the composition, production, and transport of smoke from such fires. A recent review of the state of science behind estimation of the contribution of wildland fire to greenhouse gases and black carbon in the U.S. identified several areas of research that must be performed [7]. In particular, two areas of knowledge that still need improvement are fuel characterization and smoke emissions, and the correlation(s) between the two. While many fuel types in the southeastern U.S. have been described for fire behavior and fire danger prediction, characterization of fuel bed components important for smoke production is more limited. Emissions characterization, both chemical and particulate, is needed to determine potential impacts of prescribed burning on nutrient cycling, planetary albedo, human health, and highway visibility [e.g. 8–10].

  13. Radiant zone heated particulate filter

    DOEpatents

    Gonze, Eugene V [Pinckney, MI

    2011-12-27

    A system includes a particulate matter (PM) filter including an upstream end for receiving exhaust gas and a downstream end. A radiant zoned heater includes N zones, where N is an integer greater than one, wherein each of the N zones includes M sub-zones, where M is an integer greater than or equal to one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones, restricts exhaust gas flow in a portion of the PM filter that corresponds to the selected one of the N zones, and deactivates non-selected ones of the N zones.

  14. Impact assessment of respirable suspended particulate matter from diesel generator sets used for pumping station.

    PubMed

    Talwar, B; Pipalatkar, P; Gajghate, D G; Nema, P

    2010-10-01

    Prediction of respirable suspended particulate matter impacts of diesel generator sets used for pumping station has been made using meteorological data, information on stack characteristics and emission rate, baseline ambient particulate matter and Industrial Source Complex Short Term (ISCST-3) model. It is observed that particulate matter emission from pumping station-S workplace diesel generator sets ranged from 2.4 to 436.5 mg Nm⁻³ and while at pumping station-C, it ranged from 23.2 to 186.5 mg Nm⁻³. The predicted and ambient respirable suspended particulate matter concentrations are below the national air quality standard for respirable suspended particulate matter in a mixed industrial area. Metals contents in respirable suspended particulate matter indicate the origin of crustal and mobile sources. Therefore, the impact of diesel generator sets used for pumping of crude oil on local air quality would be acceptable.

  15. Results of Self-Absorption Study on the Versapor 3000 Filters for Radioactive Particulate Air Sampling

    SciTech Connect

    Barnett, J. Matthew; Cullinan, Valerie I.; Barnett, Debra S.; Trang-Le, Truc LT; Bliss, Mary; Greenwood, Lawrence R.; Ballinger, Marcel Y.

    2009-02-17

    Since the mid-1980s, Pacific Northwest National Laboratory (PNNL) has used a value of 0.85 as the correction factor for self absorption of activity for particulate radioactive air samples collected from building exhaust for environmental monitoring. This value accounts for activity that cannot be detected by direct counting of alpha and beta particles. Emissions can be degraded or blocked by filter fibers for particles buried in the filter material or by inactive dust particles collected with the radioactive particles. These filters are used for monitoring air emissions from PNNL stacks for radioactive particles. This paper describes an effort to re-evaluate self-absorption effects in particulate radioactive air sample filters (Versapor® 3000, 47 mm diameter) used at PNNL. There were two methods used to characterize the samples. Sixty samples were selected from the archive for acid digestion to compare the radioactivity measured by direct gas-flow proportional counting of filters to the results obtained after acid digestion of the filter and counting again by gas-flow proportional detection. Thirty different sample filters were selected for visible light microscopy to evaluate filter loading and particulate characteristics. Mass-loading effects were also considered. Filter ratios were calculated by dividing the initial counts by the post-digestion counts with the expectation that post-digestion counts would be higher because digestion would expose radioactivity embedded in the filter in addition to that on top of the filter. Contrary to expectations, the post digestion readings were almost always lower than initial readings and averaged approximately half the initial readings for both alpha and beta activity. Before and after digestion readings appeared to be related to each other, but with a low coefficient of determination (R^2) value. The ratios had a wide range of values indicating that this method did not provide sufficient precision to quantify self

  16. Performance model of a recirculating stack nickel hydrogen cell

    NASA Technical Reports Server (NTRS)

    Zimmerman, Albert H.

    1994-01-01

    A theoretical model of the nickel hydrogen battery cell has been utilized to describe the chemical and physical changes during charge and overcharge in a recirculating stack nickel hydrogen cell. In particular, the movement of gas and electrolyte have been examined as a function of the amount of electrolyte put into the cell stack during cell activation, and as a function of flooding in regions of the gas screen in this cell design. Additionally, a two-dimensional variation on this model has been utilized to describe the effects of non-uniform loading in the nickel-electrode on the movement of gas and electrolyte within the recirculating stack nickel hydrogen cell. The type of nonuniform loading that has been examined here is that associated with higher than average loading near the surface of the sintered nickel electrode, a condition present to some degree in many nickel electrodes made by electrochemical impregnation methods. The effects of high surface loading were examined primarily under conditions of overcharge, since the movement of gas and electrolyte in the overcharging condition was typically where the greatest effects of non-uniform loading were found. The results indicate that significant changes in the capillary forces between cell components occur as the percentage of free volume in the stack filled by electrolyte becomes very high. These changes create large gradients in gas-filled space and oxygen concentrations near the boundary between the separator and the hydrogen electrode when the electrolyte fill is much greater than about 95 percent of the stack free volume. At lower electrolyte fill levels, these gaseous and electrolyte gradients become less extreme, and shift through the separator towards the nickel electrode. Similarly, flooding of areas in the gas screen cause higher concentrations of oxygen gas to approach the platinum/hydrogen electrode that is opposite the back side of the nickel electrode. These results illustrate the need for

  17. Multivariate analysis of mainstream tobacco smoke particulate phase by headspace solid-phase micro extraction coupled with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry.

    PubMed

    Brokl, Michał; Bishop, Louise; Wright, Christopher G; Liu, Chuan; McAdam, Kevin; Focant, Jean-François

    2014-11-28

    A method involving headspace solid-phase microextraction (HS-SPME) and comprehensive two-dimensional gas chromatography (GC×GC) coupled to time-of-flight mass spectrometry (TOFMS) was developed and applied to evaluate profiles of volatile compounds present in mainstream tobacco smoke particulate matter trapped on glass fiber filters. Six SPME fibers were tested for the extraction capacities toward selected compounds, showing the best results for the polyacrylate fiber. The optimization of the extraction conditions was carried out using multivariate response surface methodology. Two cigarette types differing in a filter design were analyzed using optimized conditions. A template was built in order to generate comprehensive chemical information, which conceded obtaining consistent information across 24 chromatograms. Principal component analysis (PCA) allowed a clear differentiation of the studied cigarette types. Fisher ratio analysis allowed identification of compounds responsible for the chemical differences between the cigarette samples. Of the selected 143 most important ones, 134 analytes were reduced by the active carbon filter, while for nine, classical cellulose acetate filter was more efficient.

  18. Monitoring of atmospheric gaseous and particulate polycyclic aromatic hydrocarbons in South African platinum mines utilising portable denuder sampling with analysis by thermal desorption-comprehensive gas chromatography-mass spectrometry.

    PubMed

    Geldenhuys, G; Rohwer, E R; Naudé, Y; Forbes, P B C

    2015-02-06

    Concentrations of diesel particulate matter and polycyclic aromatic hydrocarbons (PAHs) in platinum mine environments are likely to be higher than in ambient air due to the use of diesel machinery in confined environments. Airborne PAHs may be present in gaseous or particle phases each of which has different human health impacts due to their ultimate fate in the body. Here we report on the simultaneous sampling of both phases of airborne PAHs for the first time in underground platinum mines in South Africa, which was made possible by employing small, portable denuder sampling devices consisting of two polydimethylsiloxane (PDMS) multi-channel traps connected in series separated by a quartz fibre filter, which only require small, battery operated portable personal sampling pumps for air sampling. Thermal desorption coupled with comprehensive gas chromatography-mass spectrometry (TD-GC×GC-TofMS) was used to analyse denuder samples taken in three different platinum mines. The samples from a range of underground environments revealed that PAHs were predominantly found in the gas phase with naphthalene and mono-methylated naphthalene derivatives being detected at the highest concentrations ranging from 0.01 to 18 μg m(-3). The particle bound PAHs were found in the highest concentrations at the idling load haul dump vehicle exhausts with a dominance of fluoranthene and pyrene. Particle associated PAH concentrations ranged from 0.47 to 260 ng m(-3) and included benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene and benzo[ghi]perylene. This work highlights the need to characterise both phases in order to assess occupational exposure to PAHs in this challenging sampling environment.

  19. Remote control flare stack igniter for combustible gases

    NASA Technical Reports Server (NTRS)

    Ray, W. L.

    1972-01-01

    Device has been designed and developed for igniting nonrecoverable combustible gases and sustaining combustion of gases evolving from various gas vent stacks. Igniter is superior to existing systems because of simplicity of operation, low cost fabrication, installation, operational and maintainability features, and excellent reliability in all phases of required operations.

  20. Mobile laboratory with rapid response instruments for real-time measurements of urban and regional trace gas and particulate distributions and emission source characteristics.

    PubMed

    Kolb, Charles E; Herndon, Scott C; McManus, J Barry; Shorter, Joanne H; Zahniser, Mark S; Nelson, David D; Jayne, John T; Canagaratna, Manjula R; Worsnop, Douglas R

    2004-11-01

    Recent technological advances have allowed the development of robust, relatively compact, low power, rapid response (approximately 1 s) instruments with sufficient sensitivity and specificity to quantify many trace gases and aerosol particle components in the ambient atmosphere. Suites of such instruments can be deployed on mobile platforms to study atmospheric processes, map concentration distributions of atmospheric pollutants, and determine the composition and intensities of emission sources. A mobile laboratory containing innovative tunable infrared laser differential absorption spectroscopy (TILDAS) instruments to measure selected trace gas concentrations at sub parts-per-billion levels and an aerosol mass spectrometer (AMS) to measure size resolved distributions of the nonrefractory chemical components of fine airborne particles as well as selected commercial fast response instruments and position/velocity sensors is described. Examples of the range of measurement strategies that can be undertaken using this mobile laboratory are discussed, and samples of measurement data are presented.

  1. Fluidizing device for solid particulates

    DOEpatents

    Diebold, J.P.; Scahill, J.W.

    A flexible whip suspended in a hopper is caused to impact against fibrous and irregularly shaped particulates in the hopper to fluidize the particulates and facilitate the flow of the particulates through the hopper. The invention provides for the flow of particulates at a substantially constant mass flow rate and uses a minimum of energy.

  2. Characterizing source confusion in HI spectral line stacking experiments

    NASA Astrophysics Data System (ADS)

    Baker, Andrew J.; Elson, Edward C.; Blyth, Sarah

    2017-01-01

    Forthcoming studies like the Looking At the Distant Universe with the MeerKAT Array (LADUMA) deep HI survey will rely in part on stacking experiments to detect the mean level of HI emission from populations of galaxies that are too faint to be detected individually. Preparations for such experiments benefit from the use of synthetic data cubes built from mock galaxy catalogs and containing model galaxies with realistic spatial and spectral HI distributions over large cosmological volumes. I will present a new set of such synthetic data cubes and show the results of stacking experiments with them. Because the stacked spectra can be accurately decomposed into contributions from target and non-target galaxies, it is possible to characterize the large fractions of contaminant mass that are included in stacked totals due to source confusion. Consistent with estimates extrapolated from z = 0 observational data, we find that the amount of confused mass in a stacked spectrum grows almost linearly with the size of the observational beam, suggesting potential overestimates of the cosmic neutral gas density by some recent HI stacking experiments.

  3. Modeling of Particulate Emissions

    DTIC Science & Technology

    2011-12-01

    coagulation oxidation.... carbonization 14 Modeling Particulate Emissions Soot Formation Kinetics 2 1016 1 ]HC[kdt dS = Inception: Dimerization of...simulated with peak size for surface growth Sectional Conservation Equation 16 Modeling Particulate Emissions Soot Kinetics Based on OH, O2 and...and empirical tuning to NOx, CO emissionsFuel-spray shear layer Recirculation zones Quench zones Burn-out zones Full set of reaction kinetics and

  4. An innovative ultrasound assisted extraction micro-scale cell combined with gas chromatography/mass spectrometry in negative chemical ionization to determine persistent organic pollutants in air particulate matter.

    PubMed

    Beristain-Montiel, E; Villalobos-Pietrini, R; Arias-Loaiza, G E; Gómez-Arroyo, S L; Amador-Muñoz, O

    2016-12-16

    New clean technologies are needed to determine concentration of organic pollutants without generating more pollution. A method to extract Persistent Organic Pollutants (POPs) from airborne particulate matter was developed using a novel technology recently patented called ultrasound assisted extraction micro-scale cell (UAE-MSC). This technology extracts, filters, collects the sample, and evaporates the solvent, on-line. No sample transfer is needed. The cell minimizes sample manipulation, solvent consumption, waste generation, time, and energy; fulfilling most of the analytical green chemistry protocol. The methodology was optimized applying a centred 2(3) factorial experimental design. Optimum conditions were used to validate and determine concentration of 16 organochlorine pesticides (OCls) and 6 polybrominated diphenyl ethers (PBDEs). The best conditions achieved were 2 extractions with 5mL (each) of dichloromethane over 5min (each) at 60°C and 80% ultrasound potency. POPs were determined by gas chromatography/mass spectrometry in negative chemical ionization (GC/MS-NCI). Analytical method validation was carried out on airborne particles spiked with POPs at seven concentration levels between 0.5 and 26.9pgm(-3). This procedure was done by triplicate (N=21). Recovery, ranged between 65.5±2.3% and 107.5±3.0% for OCls and between 79.1±6.5% and 105.2±3.8% for PBDEs. Linearity (r(2)) was ≥0.94 for all compounds. Method detection limits, ranged from 0.5 to 2.7pgm(-3), while limits of quantification (LOQ), ranged from 1.7 to 9.0pgm(-3). A Bias from -18.6% to 9% for PBDEs was observed in the Standard Reference Material (SRM) 2787. SRM 2787 did not contain OCls. OCls recoveries were equivalent by UAE-MSC and Soxhlet methods UAE-MSC optimized extraction conditions reduced 30 times less solvent and decreased the extraction time from several hours to ten minutes, respect to Soxhlet. UAE-MSC was applied to 15 samples of particles less than 2.5μm (PM2.5) from three

  5. Studies on the behavior of ammonia and ammonium salts in the atmosphere (1) - Fractional collection of ammonia gas and particulate ammonium

    NASA Technical Reports Server (NTRS)

    Kiin, K.; Fujimura, M.; Hashimoto, Y.

    1981-01-01

    Methods for the fractional collection of trace amounts of atmospheric ammonia gas and ammonium particles on a two staged glass fiber filter are summarized. A standard glass fiber filter washed with distilled water and dried at 120 to 130 C was used. A second filter was impregnated with a mixture of 3% boric acid and 25% glycerin solution. The blank of glass fiber filters impregnated with a mixture of the above solution was very low for ammonia, i.e. 0.06 micrograms in a filter of 47 mm in diameter. The mean concentrations of ammonia and ammonium in air at Kawasaki, a polluted area, were 7.6 and 2.3 micrograms cu m, and those at Sanriku, an unpolluted area 0.9 and 0.2 micrograms cu m, respectively. Ratios of concentration levels of ammonium to total ammonia in the atmosphere were 0.3 and 0.2 for the polluted and unpolluted areas, respectively. Ammonium salts in air at both areas were not correlated with relative humidity. Variations in time of ammonia concentrations and sources in surrounding areas are also considered.

  6. Studies on the behavior of ammonia and ammonium salts in the atmosphere (1) - Fractional collection of ammonia gas and particulate ammonium

    NASA Astrophysics Data System (ADS)

    Kiin, K.; Fujimura, M.; Hashimoto, Y.

    1981-05-01

    Methods for the fractional collection of trace amounts of atmospheric ammonia gas and ammonium particles on a two staged glass fiber filter are summarized. A standard glass fiber filter washed with distilled water and dried at 120 to 130 C was used. A second filter was impregnated with a mixture of 3% boric acid and 25% glycerin solution. The blank of glass fiber filters impregnated with a mixture of the above solution was very low for ammonia, i.e. 0.06 micrograms in a filter of 47 mm in diameter. The mean concentrations of ammonia and ammonium in air at Kawasaki, a polluted area, were 7.6 and 2.3 micrograms cu m, and those at Sanriku, an unpolluted area 0.9 and 0.2 micrograms cu m, respectively. Ratios of concentration levels of ammonium to total ammonia in the atmosphere were 0.3 and 0.2 for the polluted and unpolluted areas, respectively. Ammonium salts in air at both areas were not correlated with relative humidity. Variations in time of ammonia concentrations and sources in surrounding areas are also considered.

  7. MTCI acoustic agglomeration particulate control

    SciTech Connect

    Chandran, R.R.; Mansour, M.N.; Scaroni, A.W.; Koopmann, G.H.; Loth, J.L.

    1994-10-01

    The overall objective of this project is to demonstrate pulse combination induced acoustic enhancement of coal ash agglomeration and sulfur capture at conditions typical of direct coal-fired turbines and PFBC hot gas cleanup. MTCI has developed an advanced compact pulse combustor island for direct coal-firing in combustion gas turbines. This combustor island comprises a coal-fired pulse combustor, a combined ash agglomeration and sulfur capture chamber (CAASCC), and a hot cyclone. In the MTCI proprietary approach, the pulse combustion-induced high intensity sound waves improve sulfur capture efficiency and ash agglomeration. The resulting agglomerates allow the use of commercial cyclones and achieve very high particulate collection efficiency. In the MTCI proprietary approach, sorbent particles are injected into a gas stream subjected to an intense acoustic field. The acoustic field serves to improve sulfur capture efficiency by enhancing both gas film and intra-particle mass transfer rates. In addition, the sorbent particles act as dynamic filter foci, providing a high density of stagnant agglomerating centers for trapping the finer entrained (in the oscillating flow field) fly ash fractions. A team has been formed with MTCI as the prime contractor and Penn State University and West Virginia University as subcontractors to MTCI. MTCI is focusing on hardware development and system demonstration, PSU is investigating and modeling acoustic agglomeration and sulfur capture, and WVU is studying aerovalve fluid dynamics. Results are presented from all three studies.

  8. Designing wet duct/stack systems for coal-fired plants

    SciTech Connect

    Anderson, D.K.; Maroti, L.A.

    2006-03-15

    A multitude of variables must be accounted for during the design and development of a wet-stack flue gas desulfurization system. The five-phase process detailed in this article has proven effective on more than 60 wet-stack system design studies. The process is the result of studies by EPRI detailed in two reports entitled: entrainment in wet stacks', and 'wet stacks design guide. A basic understanding of these concepts will help inform early design decisions and produce a system amenable to wet operation. 2 refs., 5 figs.

  9. Modeling and Qualification of a Modified Emission Unit for Radioactive Air Emissions Stack Sampling Compliance

    SciTech Connect

    Barnett, J. Matthew; Yu, Xiao-Ying; Recknagle, Kurtis P.; Glissmeyer, John A.

    2016-01-01

    A planned laboratory space and exhaust system modification to the Pacific Northwest National Laboratory Material Science and Technology Building indicated a new evaluation of the mixing at the air sampling system location would be required for compliance to ANSI/HPS N13.1-2011. The modified exhaust system would add a third fan thereby increasing the overall exhaust rate out the stack thus voiding the previous mixing study. Prior to modifying the radioactive air emissions exhaust system, a three-dimensional computational fluid dynamics computer model was used to evaluate the mixing at the sampling system location. Modeling of the new original three-fan system indicated that not all mixing criteria could be met. A second modeling effort was conducted with the addition of an air blender downstream of the confluence of the three fans which then showed satisfactory mixing results. The final installation included an air blender, and the exhaust system underwent full-scale tests to verify velocity, cyclonic flow, gas, and particulate uniformity. The modeling results and those of the full-scale tests show agreement between each of the evaluated criteria. The use of a computational fluid dynamics code was an effective aid in the design process and allowed the sampling system to remain in its original location while still meeting the requirements for sampling at a well-mixed location.

  10. Stable carbon isotope analyses of nanogram quantities of particulate organic carbon (pollen) with laser ablation nano combustion gas chromatography/isotope ratio mass spectrometry

    PubMed Central

    Sluijs, Appy; Laks, Jelmer J.; Reichart, Gert‐Jan

    2016-01-01

    Rationale Analyses of stable carbon isotope ratios (δ 13C values) of organic and inorganic matter remains have been instrumental for much of our understanding of present and past environmental and biological processes. Until recently, the analytical window of such analyses has been limited to samples containing at least several μg of carbon. Methods Here we present a setup combining laser ablation, nano combustion gas chromatography and isotope ratio mass spectrometry (LA/nC/GC/IRMS). A deep UV (193 nm) laser is used for optimal fragmentation of organic matter with minimum fractionation effects and an exceptionally small ablation chamber and combustion oven are used to reduce the minimum sample mass requirement compared with previous studies. Results Analyses of the international IAEA CH‐7 polyethylene standard show optimal accuracy, and precision better than 0.5‰, when measuring at least 42 ng C. Application to untreated modern Eucalyptus globulus (C3 plant) and Zea mays (C4 plant) pollen grains shows a ~ 16‰ offset between these species. Within each single Z. mays pollen grain, replicate analyses show almost identical δ 13C values. Conclusions Isotopic offsets between individual pollen grains exceed analytical uncertainties, therefore probably reflecting interspecimen variability of ~0.5–0.9‰. These promising results set the stage for investigating both δ 13C values and natural carbon isotopic variability between single specimens of a single population of all kinds of organic particles yielding tens of nanograms of carbon. © 2016 The Authors. Rapid Communications in Mass Spectrometry Published by John Wiley & Sons Ltd. PMID:27766694

  11. 49 CFR 178.1055 - Stacking test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Stacking test. 178.1055 Section 178.1055... Containers § 178.1055 Stacking test. (a) General. The stacking test must be conducted for the qualification of all Flexible Bulk Containers design types. (b) Special preparation for the stacking test....

  12. Characterization of flooding and two-phase flow in polymer electrolyte membrane fuel cell stacks

    NASA Astrophysics Data System (ADS)

    Karimi, G.; Jafarpour, F.; Li, X.

    A partially flooded gas diffusion layer (GDL) model is proposed and solved simultaneously with a stack flow network model to estimate the operating conditions under which water flooding could be initiated in a polymer electrolyte membrane (PEM) fuel cell stack. The models were applied to the cathode side of a stack, which is more sensitive to the inception of GDL flooding and/or flow channel two-phase flow. The model can predict the stack performance in terms of pressure, species concentrations, GDL flooding and quality distributions in the flow fields as well as the geometrical specifications of the PEM fuel cell stack. The simulation results have revealed that under certain operating conditions, the GDL is fully flooded and the quality is lower than one for parts of the stack flow fields. Effects of current density, operating pressure, and level of inlet humidity on flooding are investigated.

  13. Center for Advanced Gas Turbine Systems Research

    SciTech Connect

    Golan, L.P.

    1992-12-31

    An unregulated conventional power station based on the Rankine Cycle typically bums pulverized coal in a boiler that exports steam for expansion through a steam turbine which ultimately drives an electric generator. The flue gases are normally cleaned of particulates by an electrostatic precipitator or bag house. A basic cycle such as this will have an efficiency of approximately 35% with 10% of the energy released through the stack and 55% to cooling water. Advanced gas turbine based combustion systems have the potential to be environmentally and commercially superior to existing conventional technology. however, to date, industry, academic, and government groups have not coordinated their effort to commercialize these technologies. The Center for Advanced Gas Turbine Systems Research will provide the medium to support effective commercialization of this technology. Several cycles or concepts for advanced gas turbine systems that could be fired on natural gas or could be adapted into coal based systems have been proposed (for examples, see Figures 4, 5, 6, and 7) (2) all with vary degrees of complexity, research needs, and system potential. Natural gas fired power systems are now available with 52% efficiency ratings; however, with a focused base technology program, it is expected that the efficiency levels can be increased to the 60% level and beyond. This increase in efficiency will significantly reduce the environmental burden and reduce the cost of power generation.

  14. Center for Advanced Gas Turbine Systems Research

    SciTech Connect

    Golan, L.P.

    1992-01-01

    An unregulated conventional power station based on the Rankine Cycle typically bums pulverized coal in a boiler that exports steam for expansion through a steam turbine which ultimately drives an electric generator. The flue gases are normally cleaned of particulates by an electrostatic precipitator or bag house. A basic cycle such as this will have an efficiency of approximately 35% with 10% of the energy released through the stack and 55% to cooling water. Advanced gas turbine based combustion systems have the potential to be environmentally and commercially superior to existing conventional technology. however, to date, industry, academic, and government groups have not coordinated their effort to commercialize these technologies. The Center for Advanced Gas Turbine Systems Research will provide the medium to support effective commercialization of this technology. Several cycles or concepts for advanced gas turbine systems that could be fired on natural gas or could be adapted into coal based systems have been proposed (for examples, see Figures 4, 5, 6, and 7) (2) all with vary degrees of complexity, research needs, and system potential. Natural gas fired power systems are now available with 52% efficiency ratings; however, with a focused base technology program, it is expected that the efficiency levels can be increased to the 60% level and beyond. This increase in efficiency will significantly reduce the environmental burden and reduce the cost of power generation.

  15. Stacking interactions and DNA intercalation

    SciTech Connect

    Li, Dr. Shen; Cooper, Valentino R; Thonhauser, Prof. Timo; Lundqvist, Prof. Bengt I.; Langreth, David C.

    2009-01-01

    The relationship between stacking interactions and the intercalation of proflavine and ellipticine within DNA is investigated using a nonempirical van der Waals density functional for the correlation energy. Our results, employing a binary stack model, highlight fundamental, qualitative differences between base-pair base-pair interactions and that of the stacked intercalator base pair system. Most notable result is the paucity of torque which so distinctively defines the Twist of DNA. Surprisingly, this model, when combined with a constraint on the twist of the surrounding base-pair steps to match the observed unwinding of the sugar-phosphate backbone, was sufficient for explaining the experimentally observed proflavine intercalator configuration. Our extensive mapping of the potential energy surface of base-pair intercalator interactions can provide valuable information for future nonempirical studies of DNA intercalation dynamics.

  16. Assessment of the 296-S-21 Stack Sampling Probe Location

    SciTech Connect

    Glissmeyer, John A.

    2006-09-08

    Tests were performed to assess the suitability of the location of the air sampling probe on the 296-S-21 stack according to the criteria of ANSI N13.1-1999, Sampling and Monitoring Releases of Airborne Radioactive Substances from the Stacks and Ducts of Nuclear Facilities. Pacific Northwest National Laboratory conducted most tests on a 3.67:1 scale model of the stack. CH2MHill also performed some limited confirmatory tests on the actual stack. The tests assessed the capability of the air-monitoring probe to extract a sample representative of the effluent stream. The tests were conducted for the practical combinations of operating fans and addressed: (1) Angular Flow--The purpose is to determine whether the velocity vector is aligned with the sampling nozzle. The average yaw angle relative to the nozzle axis should not be more than 20. The measured values ranged from 5 to 11 degrees on the scale model and 10 to 12 degrees on the actual stack. (2) Uniform Air Velocity--The gas momentum across the stack cross section where the sample is extracted should be well mixed or uniform. The uniformity is expressed as the variability of the measurements about the mean, the coefficient of variance (COV). The lower the COV value, the more uniform the velocity. The acceptance criterion is that the COV of the air velocity must be ?20% across the center two-thirds of the area of the stack. At the location simulating the sampling probe, the measured values ranged form 4 to 11%, which are within the criterion. To confirm the validity of the scale model results, air velocity uniformity measurements were made both on the actual stack and on the scale model at the test ports 1.5 stack diameters upstream of the sampling probe. The results ranged from 6 to 8% COV on the actual stack and 10 to 13% COV on the scale model. The average difference for the eight runs was 4.8% COV, which is within the validation criterion. The fact that the scale model results were slightly higher than the

  17. ADVANCED HYBRID PARTICULATE COLLECTOR

    SciTech Connect

    Stanley Miller; Rich Gebert; William Swanson

    1999-11-01

    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the US Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in a manner that has not been done before. The AHPC concept consists of a combination of fabric filtration and electrostatic precipitation in the same housing, 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 emission with conventional ESPs, and it solves the problem of reentrainment and collection of dust in conventional baghouses. The AHPC is currently being tested at the 2.7-MW scale at the Big Stone power station.

  18. Void/particulate detector

    DOEpatents

    Claytor, Thomas N.; Karplus, Henry B.

    1985-01-01

    Voids and particulates are detected in a flowing stream of fluid contained in a pipe by a detector which includes three transducers spaced about the pipe. A first transducer at a first location on the pipe transmits an ultrasonic signal into the stream. A second transducer detects the through-transmission of the signal at a second location and a third transducer at a third location upstream from the first location detects the back-scattering of the signal from any voids or particulates. To differentiate between voids and particulates a fourth transducer is positioned at a fourth location which is also upstream from the first location. The back-scattered signals are normalized with the through-transmission signal to minimize temperature fluctuations.

  19. Method for immobilizing particulate materials in a packed bed

    DOEpatents

    Even, Jr., William R.; Guthrie, Stephen E.; Raber, Thomas N.; Wally, Karl; Whinnery, LeRoy L.; Zifer, Thomas

    1999-01-01

    The present invention pertains generally to immobilizing particulate matter contained in a "packed" bed reactor so as to prevent powder migration, compaction, coalescence, or the like. More specifically, this invention relates to a technique for immobilizing particulate materials using a microporous foam-like polymer such that a) the particulate retains its essential chemical nature, b) the local movement of the particulate particles is not unduly restricted, c) bulk powder migration and is prevented, d) physical and chemical access to the particulate is unchanged over time, and e) very high particulate densities are achieved. The immobilized bed of the present invention comprises a vessel for holding particulate matter, inlet and an outlet ports or fittings, a loosely packed bed of particulate material contained within the vessel, and a three dimensional porous matrix for surrounding and confining the particles thereby fixing the movement of individual particle to a limited local position. The established matrix is composed of a series of cells or chambers comprising walls surrounding void space, each wall forming the wall of an adjacent cell; each wall containing many holes penetrating through the wall yielding an overall porous structure and allowing useful levels of gas transport.

  20. Method for immobilizing particulate materials in a packed bed

    DOEpatents

    Even, W.R. Jr.; Guthrie, S.E.; Raber, T.N.; Wally, K.; Whinnery, L.L.; Zifer, T.

    1999-02-02

    The present invention pertains generally to immobilizing particulate matter contained in a packed bed reactor so as to prevent powder migration, compaction, coalescence, or the like. More specifically, this invention relates to a technique for immobilizing particulate materials using a microporous foam-like polymer such that (a) the particulate retains its essential chemical nature, (b) the local movement of the particulate particles is not unduly restricted, (c) bulk powder migration and is prevented, (d) physical and chemical access to the particulate is unchanged over time, and (e) very high particulate densities are achieved. The immobilized bed of the present invention comprises a vessel for holding particulate matter, inlet and an outlet ports or fittings, a loosely packed bed of particulate material contained within the vessel, and a three dimensional porous matrix for surrounding and confining the particles thereby fixing the movement of an individual particle to a limited local position. The established matrix is composed of a series of cells or chambers comprising walls surrounding void space, each wall forming the wall of an adjacent cell; each wall containing many holes penetrating through the wall yielding an overall porous structure and allowing useful levels of gas transport. 4 figs.

  1. Microwave regenerated particulate trap

    SciTech Connect

    McDonald, A.C. Jr.; Yonushonis, T.M.; Haberkamp, W.C.; Mako, F.; Len, L.K,; Silberglitt, R.; Ahmed, I.

    1997-12-31

    It has been demonstrated that a fibrous particulate filter can extract particulate matter from the diesel exhaust. However, additional engineering efforts remains to achieve the design target of 90%. It has also be shown that with minor modifications magnetrons produced for home ovens can endure a simulated diesel operating environment. Much work remains to develop a robust product ready to complete extensive engine testing and evaluation. These efforts include: (1) additional environmental testing of magnetrons; (2) vibration testing of the filter in the housing; (3) evaluating alternative methods/designs to seal the center bore; and (4) determining the optimum coating thickness that provides sufficient structural integrity while maintaining rapid heating rates.

  2. Pressurized electrolysis stack with thermal expansion capability

    DOEpatents

    Bourgeois, Richard Scott

    2015-07-14

    The present techniques provide systems and methods for mounting an electrolyzer stack in an outer shell so as to allow for differential thermal expansion of the electrolyzer stack and shell. Generally, an electrolyzer stack may be formed from a material with a high coefficient of thermal expansion, while the shell may be formed from a material having a lower coefficient of thermal expansion. The differences between the coefficients of thermal expansion may lead to damage to the electrolyzer stack as the shell may restrain the thermal expansion of the electrolyzer stack. To allow for the differences in thermal expansion, the electrolyzer stack may be mounted within the shell leaving a space between the electrolyzer stack and shell. The space between the electrolyzer stack and the shell may be filled with a non-conductive fluid to further equalize pressure inside and outside of the electrolyzer stack.

  3. 40 CFR 52.2276 - Control strategy and regulations: Particulate matter.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... on the primary crusher and on the secondary crusher and screens, meeting the requirements of Appendix... crusher and shall not emit particulate matter in excess of 0.03 grains per standard cubic foot from the exhaust stack of the fabric filter on its secondary crusher and screens....

  4. 40 CFR 52.2276 - Control strategy and regulations: Particulate matter.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... on the primary crusher and on the secondary crusher and screens, meeting the requirements of Appendix... crusher and shall not emit particulate matter in excess of 0.03 grains per standard cubic foot from the exhaust stack of the fabric filter on its secondary crusher and screens....

  5. 40 CFR 52.2276 - Control strategy and regulations: Particulate matter.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... on the primary crusher and on the secondary crusher and screens, meeting the requirements of Appendix... crusher and shall not emit particulate matter in excess of 0.03 grains per standard cubic foot from the exhaust stack of the fabric filter on its secondary crusher and screens....

  6. 40 CFR 52.2276 - Control strategy and regulations: Particulate matter.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... on the primary crusher and on the secondary crusher and screens, meeting the requirements of Appendix... crusher and shall not emit particulate matter in excess of 0.03 grains per standard cubic foot from the exhaust stack of the fabric filter on its secondary crusher and screens....

  7. 40 CFR 52.2276 - Control strategy and regulations: Particulate matter.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... on the primary crusher and on the secondary crusher and screens, meeting the requirements of Appendix... crusher and shall not emit particulate matter in excess of 0.03 grains per standard cubic foot from the exhaust stack of the fabric filter on its secondary crusher and screens....

  8. Progress Update: Stack Project Complete

    ScienceCinema

    Cody, Tom

    2016-07-12

    Progress update from the Savannah River Site. The 75 foot 293 F Stack, built for plutonium production, was cut down to size in order to prevent injury or release of toxic material if the structure were to collapse due to harsh weather.

  9. Multibeam collimator uses prism stack

    NASA Technical Reports Server (NTRS)

    Minott, P. O.

    1981-01-01

    Optical instrument creates many divergent light beams for surveying and machine element alignment applications. Angles and refractive indices of stack of prisms are selected to divert incoming laser beam by small increments, different for each prism. Angles of emerging beams thus differ by small, precisely-controlled amounts. Instrument is nearly immune to vibration, changes in gravitational force, temperature variations, and mechanical distortion.

  10. Multilayer Piezoelectric Stack Actuator Characterization

    NASA Technical Reports Server (NTRS)

    Sherrit, Stewart; Jones, Christopher M.; Aldrich, Jack B.; Blodget, Chad; Bao, Xioaqi; Badescu, Mircea; Bar-Cohen, Yoseph

    2008-01-01

    Future NASA missions are increasingly seeking to use actuators for precision positioning to accuracies of the order of fractions of a nanometer. For this purpose, multilayer piezoelectric stacks are being considered as actuators for driving these precision mechanisms. In this study, sets of commercial PZT stacks were tested in various AC and DC conditions at both nominal and extreme temperatures and voltages. AC signal testing included impedance, capacitance and dielectric loss factor of each actuator as a function of the small-signal driving sinusoidal frequency, and the ambient temperature. DC signal testing includes leakage current and displacement as a function of the applied DC voltage. The applied DC voltage was increased to over eight times the manufacturers' specifications to investigate the correlation between leakage current and breakdown voltage. Resonance characterization as a function of temperature was done over a temperature range of -180C to +200C which generally exceeded the manufacturers' specifications. In order to study the lifetime performance of these stacks, five actuators from one manufacturer were driven by a 60volt, 2 kHz sine-wave for ten billion cycles. The tests were performed using a Lab-View controlled automated data acquisition system that monitored the waveform of the stack electrical current and voltage. The measurements included the displacement, impedance, capacitance and leakage current and the analysis of the experimental results will be presented.

  11. Progress Update: Stack Project Complete

    SciTech Connect

    Cody, Tom

    2010-01-01

    Progress update from the Savannah River Site. The 75 foot 293 F Stack, built for plutonium production, was cut down to size in order to prevent injury or release of toxic material if the structure were to collapse due to harsh weather.

  12. Late Pleistocene Sea Level Stack

    NASA Astrophysics Data System (ADS)

    Spratt, R. M.; Lisiecki, L. E.

    2014-12-01

    Sea level reconstructions have been created using wide variety of proxies and models. The accuracy of individual sea level reconstructions is limited by measurement, noise, local variations in salinity and temperature, and the assumptions particular to each reconstruction. To address these limitations, we have created a sea level stack (average) which increases the signal-to-noise ratio of sea level estimates by combining 5-7 sea level reconstructions over the last 800 kyr. Principal Component analysis (PCA) of seven sea level records from 0-430 kyr ago shows that 82% of the variance in these records is explained by their first principal component (i.e., the stack). Additionally, a stack of just the 5 longer records that extends to 800 kyr closely matches the timing and amplitude of our seven-record mean. We find that the mean sea level estimate for Marine Isotope Stage (MIS) 5e is 0-4 m above modern, and that the standard deviation of individual estimates is 11 m. Mean sea level estimates for MIS 11 are 12-16 m above modern with a standard deviation of 30 m. Due to the large variability between individual reconstructions, our sea level stack may provide more robust sea level estimates than any single technique.

  13. Multilayer piezoelectric stack actuator characterization

    NASA Astrophysics Data System (ADS)

    Sherrit, Stewart; Jones, Christopher M.; Aldrich, Jack B.; Blodget, Chad; Bao, Xioaqi; Badescu, Mircea; Bar-Cohen, Yoseph

    2008-03-01

    Future NASA missions are increasingly seeking to use actuators for precision positioning to accuracies of the order of fractions of a nanometer. For this purpose, multilayer piezoelectric stacks are being considered as actuators for driving these precision mechanisms. In this study, sets of commercial PZT stacks were tested in various AC and DC conditions at both nominal and extreme temperatures and voltages. AC signal testing included impedance, capacitance and dielectric loss factor of each actuator as a function of the small-signal driving sinusoidal frequency, and the ambient temperature. DC signal testing includes leakage current and displacement as a function of the applied DC voltage. The applied DC voltage was increased to over eight times the manufacturers' specifications to investigate the correlation between leakage current and breakdown voltage. Resonance characterization as a function of temperature was done over a temperature range of -180°C to +200°C which generally exceeded the manufacturers' specifications. In order to study the lifetime performance of these stacks, five actuators from one manufacturer were driven by a 60volt, 2 kHz sine-wave for ten billion cycles. The tests were performed using a Lab-View controlled automated data acquisition system that monitored the waveform of the stack electrical current and voltage. The measurements included the displacement, impedance, capacitance and leakage current and the analysis of the experimental results will be presented.

  14. Manifold seal structure for fuel cell stack

    DOEpatents

    Collins, William P.

    1988-01-01

    The seal between the sides of a fuel cell stack and the gas manifolds is improved by adding a mechanical interlock between the adhesive sealing strip and the abutting surface of the manifolds. The adhesive is a material which can flow to some extent when under compression, and the mechanical interlock is formed providing small openings in the portion of the manifold which abuts the adhesive strip. When the manifolds are pressed against the adhesive strips, the latter will flow into and through the manifold openings to form buttons or ribs which mechanically interlock with the manifolds. These buttons or ribs increase the bond between the manifolds and adhesive, which previously relied solely on the adhesive nature of the adhesive.

  15. Fluidizing device for solid particulates

    DOEpatents

    Diebold, J.P.; Scahill, J.W.

    1984-06-27

    A flexible whip or a system of whips with novel attachments is suspended in a hopper and is caused to impact against fibrous and irregularly shaped particulates in the hopper to fluidize the particulates and facilitate the flow of the particulates through the hopper. The invention provides for the flow of particulates at a substantially constant mass flow rate and uses a minimum of energy.

  16. Fluidizing device for solid particulates

    DOEpatents

    Diebold, James P.; Scahill, John W.

    1986-01-01

    A flexible whip or a system of whips with novel attachments is suspended in a hopper and is caused to impact against fibrous and irregularly shaped particulates in the hopper to fluidize the particulates and facilitate the flow of the particulates through the hopper. The invention provides for the flow of particulates at a substantially constant mass flow rate and uses a minimum of energy.

  17. Development and Applications of a Stage Stacking Procedure

    NASA Technical Reports Server (NTRS)

    Kulkarni, Sameer; Celestina, Mark L.; Adamczyk, John J.

    2012-01-01

    The preliminary design of multistage axial compressors in gas turbine engines is typically accomplished with mean-line methods. These methods, which rely on empirical correlations, estimate compressor performance well near the design point, but may become less reliable off-design. For land-based applications of gas turbine engines, off-design performance estimates are becoming increasingly important, as turbine plant operators desire peaking or load-following capabilities and hot-day operability. The current work develops a one-dimensional stage stacking procedure, including a newly defined blockage term, which is used to estimate the off-design performance and operability range of a 13-stage axial compressor used in a power generating gas turbine engine. The new blockage term is defined to give mathematical closure on static pressure, and values of blockage are shown to collapse to curves as a function of stage inlet flow coefficient and corrected shaft speed. In addition to these blockage curves, the stage stacking procedure utilizes stage characteristics of ideal work coefficient and adiabatic efficiency. These curves are constructed using flow information extracted from computational fluid dynamics (CFD) simulations of groups of stages within the compressor. Performance estimates resulting from the stage stacking procedure are shown to match the results of CFD simulations of the entire compressor to within 1.6% in overall total pressure ratio and within 0.3 points in overall adiabatic efficiency. Utility of the stage stacking procedure is demonstrated by estimation of the minimum corrected speed which allows stable operation of the compressor. Further utility of the stage stacking procedure is demonstrated with a bleed sensitivity study, which estimates a bleed schedule to expand the compressors operating range.

  18. Analysis of microsize particulates

    NASA Technical Reports Server (NTRS)

    Blanchard, M. B.; Farlow, N. H.; Ferry, G. V.

    1972-01-01

    Unique methods for analyzing individual particles ranging in size from 0.01 to 1000 micrometers have been developed for investigation of nature of cosmic dust. Methods are applicable to particulate aerosols and contaminants characteristically encountered in studies of air pollution and in experiments designed to abate pollution.

  19. Development of a polymer electrolyte membrane fuel cell stack for an underwater vehicle

    NASA Astrophysics Data System (ADS)

    Han, In-Su; Kho, Back-Kyun; Cho, Sungbaek

    2016-02-01

    This paper presents a polymer electrolyte membrane (PEM) fuel cell stack that is specifically designed for the propulsion of an underwater vehicle (UV). The stack for a UV must be continuously operated in a closed space using hydrogen and pure oxygen; it should meet various performance requirements such as high hydrogen and oxygen utilizations, low hydrogen and oxygen consumptions, a high ramp-up rate, and a long lifetime. To this end, a cascade-type stack design is employed and the cell components, including the membrane electrode assembly and bipolar plate, are evaluated using long-term performance tests. The feasibility of a fabricated 4-kW-class stack was confirmed through various performance evaluations. The proposed cascade-type stack exhibited a high efficiency of 65% and high hydrogen and oxygen utilizations of 99.89% and 99.68%, respectively, resulting in significantly lesser purge-gas emissions to the outside of the stack. The load-following test was successfully performed at a high ramp-up rate. The lifetime of the stack was confirmed by a 3500-h performance test, from which the degradation rate of the cell voltage was obtained. The advantages of the cascade-type stack were also confirmed by comparing its performance with that of a single-stage stack operating in dead-end mode.

  20. Gas cleaning system and method

    DOEpatents

    Newby, Richard Allen

    2006-06-06

    A gas cleaning system for removing at least a portion of contaminants, such as halides, sulfur, particulates, mercury, and others, from a synthesis gas (syngas). The gas cleaning system may include one or more filter vessels coupled in series for removing halides, particulates, and sulfur from the syngas. The gas cleaning system may be operated by receiving gas at a first temperature and pressure and dropping the temperature of the syngas as the gas flows through the system. The gas cleaning system may be used for an application requiring clean syngas, such as, but not limited to, fuel cell power generation, IGCC power generation, and chemical synthesis.

  1. Advanced Fine Particulate Characterization Methods

    SciTech Connect

    Steven Benson; Lingbu Kong; Alexander Azenkeng; Jason Laumb; Robert Jensen; Edwin Olson; Jill MacKenzie; A.M. Rokanuzzaman

    2007-01-31

    The characterization and control of emissions from combustion sources are of significant importance in improving local and regional air quality. Such emissions include fine particulate matter, organic carbon compounds, and NO{sub x} and SO{sub 2} gases, along with mercury and other toxic metals. This project involved four activities including Further Development of Analytical Techniques for PM{sub 10} and PM{sub 2.5} Characterization and Source Apportionment and Management, Organic Carbonaceous Particulate and Metal Speciation for Source Apportionment Studies, Quantum Modeling, and High-Potassium Carbon Production with Biomass-Coal Blending. The key accomplishments included the development of improved automated methods to characterize the inorganic and organic components particulate matter. The methods involved the use of scanning electron microscopy and x-ray microanalysis for the inorganic fraction and a combination of extractive methods combined with near-edge x-ray absorption fine structure to characterize the organic fraction. These methods have direction application for source apportionment studies of PM because they provide detailed inorganic analysis along with total organic and elemental carbon (OC/EC) quantification. Quantum modeling using density functional theory (DFT) calculations was used to further elucidate a recently developed mechanistic model for mercury speciation in coal combustion systems and interactions on activated carbon. Reaction energies, enthalpies, free energies and binding energies of Hg species to the prototype molecules were derived from the data obtained in these calculations. Bimolecular rate constants for the various elementary steps in the mechanism have been estimated using the hard-sphere collision theory approximation, and the results seem to indicate that extremely fast kinetics could be involved in these surface reactions. Activated carbon was produced from a blend of lignite coal from the Center Mine in North Dakota and

  2. Helping Students Design HyperCard Stacks.

    ERIC Educational Resources Information Center

    Dunham, Ken

    1995-01-01

    Discusses how to teach students to design HyperCard stacks. Highlights include introducing HyperCard, developing storyboards, introducing design concepts and scripts, presenting stacks, evaluating storyboards, and continuing projects. A sidebar presents a HyperCard stack evaluation form. (AEF)

  3. 49 CFR 178.980 - Stacking test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Stacking test. 178.980 Section 178.980... Packagings § 178.980 Stacking test. (a) General. The stacking test must be conducted for the qualification of... test. (1) All Large Packagings except flexible Large Packaging design types must be loaded to...

  4. 49 CFR 178.606 - Stacking test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Stacking test. 178.606 Section 178.606... Packagings and Packages § 178.606 Stacking test. (a) General. All packaging design types other than bags must be subjected to a stacking test. (b) Number of test samples. Three test samples are required for...

  5. PRECISION COSMOGRAPHY WITH STACKED VOIDS

    SciTech Connect

    Lavaux, Guilhem; Wandelt, Benjamin D.

    2012-08-01

    We present a purely geometrical method for probing the expansion history of the universe from the observation of the shape of stacked voids in spectroscopic redshift surveys. Our method is an Alcock-Paczynski (AP) test based on the average sphericity of voids posited on the local isotropy of the universe. It works by comparing the temporal extent of cosmic voids along the line of sight with their angular, spatial extent. We describe the algorithm that we use to detect and stack voids in redshift shells on the light cone and test it on mock light cones produced from N-body simulations. We establish a robust statistical model for estimating the average stretching of voids in redshift space and quantify the contamination by peculiar velocities. Finally, assuming that the void statistics that we derive from N-body simulations is preserved when considering galaxy surveys, we assess the capability of this approach to constrain dark energy parameters. We report this assessment in terms of the figure of merit (FoM) of the dark energy task force and in particular of the proposed Euclid mission which is particularly suited for this technique since it is a spectroscopic survey. The FoM due to stacked voids from the Euclid wide survey may double that of all other dark energy probes derived from Euclid data alone (combined with Planck priors). In particular, voids seem to outperform baryon acoustic oscillations by an order of magnitude. This result is consistent with simple estimates based on mode counting. The AP test based on stacked voids may be a significant addition to the portfolio of major dark energy probes and its potentialities must be studied in detail.

  6. Particulate contamination removal from wafers using plasmas and mechanical agitation

    DOEpatents

    Selwyn, G.S.

    1998-12-15

    Particulate contamination removal from wafers is disclosed using plasmas and mechanical agitation. The present invention includes the use of plasmas with mechanical agitation for removing particulate matter from the surface of a wafer. The apparatus hereof comprises a mechanical activator, at least one conducting contact pin for transferring the vibration from the activator to the wafer, clamp fingers that maintain the wafer`s position, and means for generating a plasma in the vicinity of the surface of the wafer, all parts of the cleaning apparatus except the mechanical activator and part of the contact pin being contained inside the processing chamber. By exposing a wafer to a plasma and providing motion thereto in a direction perpendicular to its surface, the bonding between the particulate matter and the surface may be overcome. Once free of the wafer surface, the particulates become charged by electrons from the plasma and are drawn into the plasma by attractive forces which keep them from redepositing. The introduction of a flowing gas through the plasma sweeps the particulates away from the wafer and out of the plasma. The entire surface is cleaned during one cleaning step. The use of an rf plasma to accomplish the particulate removal was found to remove more than 90% of the particulates. 4 figs.

  7. Particulate contamination removal from wafers using plasmas and mechanical agitation

    DOEpatents

    Selwyn, Gary S.

    1998-01-01

    Particulate contamination removal from wafers using plasmas and mechanical agitation. The present invention includes the use of plasmas with mechanical agitation for removing particulate matter from the surface of a wafer. The apparatus hereof comprises a mechanical activator, at least one conducting contact pin for transferring the vibration from the activator to the wafer, clamp fingers that maintain the wafer's position, and means for generating a plasma in the vicinity of the surface of the wafer, all parts of the cleaning apparatus except the mechanical activator and part of the contact pin being contained inside the processing chamber. By exposing a wafer to a plasma and providing motion thereto in a direction perpendicular to its surface, the bonding between the particulate matter and the surface may be overcome. Once free of the wafer surface, the particulates become charged by electrons from the plasma and are drawn into the plasma by attractive forces which keep them from redepositing. The introduction of a flowing gas through the plasma sweeps the particulates away from the wafer and out of the plasma. The entire surface is cleaned during one cleaning step. The use of an rf plasma to accomplish the particulate removal was found to remove more than 90% of the particulates.

  8. Experimental performance evaluation of two stack sampling systems in a plutonium facility

    SciTech Connect

    Glissmeyer, J.A.

    1992-04-01

    The evaluation of two routine stack sampling systems at the Z-Plant plutonium facility operated by Rockwell International for USERDA is part of a larger study, sponsored by Rockwell and conducted by Battelle, Pacific Northwest Laboratories, of gaseous effluent sampling systems. The gaseous effluent sampling systems evaluated are located at the main plant ventilation stack (291-Z-1) and at a vessel vent stack (296-Z-3). A preliminary report, which was a paper study issued in April 1976, identified many deficiencies in the existing sampling systems and made recommendations for corrective action. The objectives of this experimental evaluation of those sampling systems were as follows: Characterize the radioactive aerosols in the stack effluents; Develop a tracer aerosol technique for validating particulate effluent sampling system performance; Evaluate the performance of the existing routine sampling systems and their compliance with the sponsor`s criteria; and Recommend corrective action where required. The tracer aerosol approach to sampler evaluation was chosen because the low concentrations of radioactive particulates in the effluents would otherwise require much longer sampling times and thus more time to complete this evaluation. The following report describes the sampling systems that are the subject of this study and then details the experiments performed. The results are then presented and discussed. Much of the raw and finished data are included in the appendices.

  9. Rigid particulate matter sensor

    SciTech Connect

    Hall, Matthew

    2011-02-22

    A sensor to detect particulate matter. The sensor includes a first rigid tube, a second rigid tube, a detection surface electrode, and a bias surface electrode. The second rigid tube is mounted substantially parallel to the first rigid tube. The detection surface electrode is disposed on an outer surface of the first rigid tube. The detection surface electrode is disposed to face the second rigid tube. The bias surface electrode is disposed on an outer surface of the second rigid tube. The bias surface electrode is disposed to face the detection surface electrode on the first rigid tube. An air gap exists between the detection surface electrode and the bias surface electrode to allow particulate matter within an exhaust stream to flow between the detection and bias surface electrodes.

  10. Testing the sampling efficiency of a nuclear power station stack monitor

    SciTech Connect

    Stroem, L.H.

    1997-08-01

    The test method comprises the injection of known amounts of monodisperse particles in the stack air stream, at a suitable point upstream of the sampling installation. To find a suitable injection polls, the gas flow was mapped by means of a tracer gas, released in various points in the stack base. The resulting concentration distributions at the stack sampler level were observed by means of an array of gas detectors. An injection point that produced symmetrical distribution over the stack area, and low concentrations at the stack walls was selected for the particle tests. Monodisperse particles of 6, 10, and 19 {mu}m aerodynamic diameter, tagged with dysprosium, were dispersed in the selected injection point. Particle concentration at the sampler level was measured. The losses to the stack walls were found to be less than 10 %. The particle concentrations at the four sampler inlets were calculated from the observed gas distribution. The amount calculated to be aspirated into the sampler piping was compared with the quantity collected by the sampling train ordinary filter, to obtain the sampling line transmission efficiency. 1 ref., 2 figs.

  11. Stacks

    ERIC Educational Resources Information Center

    Kimber, Lizzie

    2010-01-01

    Linton Waters and Jayne Kranat ran a session on the Nuffield "Applying Mathematical Processes" (AMP) activities at BCME7 in Manchester in April this year. These 1-2 hour activities are revamps of some of the Graded Assessment in Mathematics (GAIM) resources, developed in the 1980s, and are freely available via the Nuffield website and…

  12. Economic recovery and utilization of boiler flue gas pollutants

    SciTech Connect

    Johnson, A.F.; Sackett, R.L.

    1991-10-29

    This patent describes a method of removing unwanted pollutants from flue gas streams from power plants. It comprises passing flue gas containing lime, sulphur dioxide and water in succession through at least three vertically extending beds of particulates, the particulates being disposed in a duct such that the flue gas is passed through substantially all of the particulates, reacting lime, sulphur dioxide and water in the flue gas to form gypsum at a first bed of particulates; reacting sulphur dioxide and water in the flue gas to form sulphuric acid, and collecting sulphuric acid below its condensation temperature at a second bed of particulates; reacting sulphur dioxide in the flue gas with an alkali material to form bisulphites and bisulphates at a third bed of particulates; and removing the pollutants from the particulates of the beds.

  13. Characterisation of particulate matter emissions from the Zimbabwe Mining and Smelting Company (ZIMASCO) Kwekwe Division (Zimbabwe): a ferrochrome smelter.

    PubMed

    Pumure, I; Sithole, S D; Kahwai, S G T

    2003-09-01

    Particulate matter emissions from stack number 2 of a major ferrochrome smelter, Zimbabwe Mining and Smelting Company (ZIMASCO) were characterized and the rates at which the elements Cr, Fe, Cu and Zn and total ferrochrome dust are emitted into the atmosphere were determined. The extent of soil contamination by the dust deposited around the smelter in the generally prevailing southeasterly wind direction around the smelter was carried out. The highest concentrations of Cr and Fe occurred in the fine particulates of sizes less than 59 microm whilst that of Cu and Zn occurred in the coarse particulates of size range 70-100 microm. The emission rates from stack 2 were; total ferrochrome particulates 62.17 kg h(-1), Cr 6.217 kg h(-1), Fe 2.423 kg h(-1), Zn 42 mg h(-1) and 6 mg h(-1) for Cu. Particulate matter was emitted at a rate of 289 mg m(-3) from stack number 2. This value exceeds the legal limit of 200 mg m(-3). Chromium and iron are the metals in the largest amounts. The particles that constitute the largest proportion of the dust were in the range of 58-107.5 microm. This is a characteristic feature of the particulate matter emissions from ZIMASCO. Soils in the downwind direction from the smelter were polluted with Cr up to a distance of about 700 m outward from the perimeter of the boundary of the smelter.

  14. Gas sensor

    SciTech Connect

    Schmid, Andreas K.; Mascaraque, Arantzazu; Santos, Benito; de la Figuera, Juan

    2014-09-09

    A gas sensor is described which incorporates a sensor stack comprising a first film layer of a ferromagnetic material, a spacer layer, and a second film layer of the ferromagnetic material. The first film layer is fabricated so that it exhibits a dependence of its magnetic anisotropy direction on the presence of a gas, That is, the orientation of the easy axis of magnetization will flip from out-of-plane to in-plane when the gas to be detected is present in sufficient concentration. By monitoring the change in resistance of the sensor stack when the orientation of the first layer's magnetization changes, and correlating that change with temperature one can determine both the identity and relative concentration of the detected gas. In one embodiment the stack sensor comprises a top ferromagnetic layer two mono layers thick of cobalt deposited upon a spacer layer of ruthenium, which in turn has a second layer of cobalt disposed on its other side, this second cobalt layer in contact with a programmable heater chip.

  15. Lightweight Stacks of Direct Methanol Fuel Cells

    NASA Technical Reports Server (NTRS)

    Narayanan, Sekharipuram; Valdez, Thomas

    2004-01-01

    An improved design concept for direct methanol fuel cells makes it possible to construct fuel-cell stacks that can weigh as little as one-third as much as do conventional bipolar fuel-cell stacks of equal power. The structural-support components of the improved cells and stacks can be made of relatively inexpensive plastics. Moreover, in comparison with conventional bipolar fuel-cell stacks, the improved fuel-cell stacks can be assembled, disassembled, and diagnosed for malfunctions more easily. These improvements are expected to bring portable direct methanol fuel cells and stacks closer to commercialization. In a conventional bipolar fuel-cell stack, the cells are interspersed with bipolar plates (also called biplates), which are structural components that serve to interconnect the cells and distribute the reactants (methanol and air). The cells and biplates are sandwiched between metal end plates. Usually, the stack is held together under pressure by tie rods that clamp the end plates. The bipolar stack configuration offers the advantage of very low internal electrical resistance. However, when the power output of a stack is only a few watts, the very low internal resistance of a bipolar stack is not absolutely necessary for keeping the internal power loss acceptably low.

  16. 30 CFR 250.442 - What are the requirements for a subsea BOP stack?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations...) When you drill with a subsea BOP stack, you must install the BOP system before drilling below surface casing. The District Manager may require you to install a subsea BOP system before drilling below...

  17. 30 CFR 250.441 - What are the requirements for a surface BOP stack?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations...? (a) When you drill with a surface BOP stack, you must install the BOP system before drilling below... with blind-shear rams. The blind-shear rams must be capable of shearing the drill pipe that is in...

  18. 30 CFR 250.441 - What are the requirements for a surface BOP stack?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... stack? 250.441 Section 250.441 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Blowout Preventer (bop) System Requirements § 250.441 What are...

  19. MERCURY CONTROL WITH ADVANCED HYBRID PARTICULATE COLLECTOR

    SciTech Connect

    Ye Zhuang; Stanley J. Miller

    2005-05-01

    This project was awarded under U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) Program Solicitation DE-PS26-00NT40769 and specifically addressed Technical Topical Area 4-Testing Novel and Less Mature Control Technologies on Actual Flue Gas at the Pilot Scale. The project team included 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 Power 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 & Associates, Inc., and has been marketed as the Advanced Hybrid{trademark} filter by Gore. The Advanced Hybrid{trademark} filter 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 Advanced Hybrid{trademark} filter 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 Advanced Hybrid{trademark} filter also appears to have unique advantages for mercury control over baghouses or ESPs as an excellent gas--solid contactor. The objective of the project was to demonstrate 90% total mercury control in the Advanced Hybrid{trademark} filter at a lower cost than current mercury control estimates. The approach included bench-scale batch tests, larger-scale pilot testing with real flue gas on a coal-fired combustion system, and field demonstration at the 2.5-MW (9000-acfm) scale at a utility power plant to prove scale-up and demonstrate longer-term mercury control

  20. 77 FR 10323 - Revisions to Federal Implementation Plans To Reduce Interstate Transport of Fine Particulate...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-21

    ... Implementation Plans To Reduce Interstate Transport of Fine Particulate Matter and Ozone; Final Rule #0;#0... To Reduce Interstate Transport of Fine Particulate Matter and Ozone AGENCY: Environmental Protection... assumptions regarding flue gas treatment in existing scrubbers at seven units; (4) revise the Arkansas...

  1. QUANTITATION, DETECTION AND MEASUREMENT PRECISION OF ORGANIC MOLECULAR MARKERS IN URBAN PARTICULATE MATTER FROM PHILADELPHIA, PA

    EPA Science Inventory

    This work focuses on analysis of organic molecular markers in airborne particulate matter (PM) by Gas Chromatography/Ion Trap Mass Spectrometry (GC/IT MS). The particulate samples used in the method development were collected as PM10 in metropolitan Philadelphia during...

  2. Scaled tests and modeling of effluent stack sampling location mixing.

    PubMed

    Recknagle, Kurtis P; Yokuda, Satoru T; Ballinger, Marcel Y; Barnett, J Matthew

    2009-02-01

    A three-dimensional computational fluid dynamics computer model was used to evaluate the mixing at a sampling system for radioactive air emissions. Researchers sought to determine whether the location would meet the criteria for uniform air velocity and contaminant concentration as prescribed in the American National Standards Institute standard, Sampling and Monitoring Releases of Airborne Radioactive Substances from the Stacks and Ducts of Nuclear Facilities. This standard requires that the sampling location be well-mixed and stipulates specific tests to verify the extent of mixing. The exhaust system for the Radiochemical Processing Laboratory was modeled with a computational fluid dynamics code to better understand the flow and contaminant mixing and to predict mixing test results. The modeled results were compared to actual measurements made at a scale-model stack and to the limited data set for the full-scale facility stack. Results indicated that the computational fluid dynamics code provides reasonable predictions for velocity, cyclonic flow, gas, and aerosol uniformity, although the code predicts greater improvement in mixing as the injection point is moved farther away from the sampling location than is actually observed by measurements. In expanding from small to full scale, the modeled predictions for full-scale measurements show similar uniformity values as in the scale model. This work indicated that a computational fluid dynamics code can be a cost-effective aid in designing or retrofitting a facility's stack sampling location that will be required to meet standard ANSI/HPS N13.1-1999.

  3. Formation and atomic structure of boron nitride nanotubes with a cup-stacked structure

    NASA Astrophysics Data System (ADS)

    Oku, Takeo; Koi, Naruhiro; Suganuma, Katsuaki; Belosludov, Rodion V.; Kawazoe, Yoshiyuki

    2007-08-01

    Boron nitride (BN) nanotubes were synthesized by annealing Fe 4N/B powder at 1000 ∘C for 1 h in a nitrogen gas atmosphere, and large amounts of BN nanotubes with a cup-stacked structure were obtained after a purification process. The atomic structures of the cup-stacked BN nanotubes were investigated by high-resolution electron microscopy as well as molecular mechanics calculations, and compared with double walled BN nanotubes. The present results indicate that the cup-stacked structure with a cone angle of 20 ∘ is more stable than the structure with an angle of 38 ∘ and ordinary nanotube structures.

  4. Electrostatic precipitator for metal and particulate emission control

    SciTech Connect

    Yang, C.L.; Beltran, M.

    2000-03-01

    Improving air pollution control systems is crucial for incinerators to be an option for sewage sludge disposal. Combinations of venturi and tray tower scrubbers are the most popular air pollution control system for sewage sludge incinerators. Recently wet electrostatic precipitators have been installed downstream of the scrubbing system to ensure the compliance of new regulations. Performance and stack tests were conducted on sludge incinerators at Somerset Raritan Valley Sewage Authority and New England Treatment Company. Efficiencies in terms of heavy metal and particulate removals are presented. This paper also describes sewage sludge incinerators, existing air pollution control systems, design considerations of the wet electrostatic precipitator, as well as sampling and analysis methods.

  5. Status of MCFC stack development at Hitachi

    SciTech Connect

    Takashima, S.; Kahara, T.; Takeuchi, M.

    1996-12-31

    Hitachi, Ltd. has been developing Molten Carbonate Fuel Cells in the New Sunshine project in Japan, and Hitachi is taking part in the development of 1,000kW MCFC pilot plant at Kawagoe. Hitachi is engaged in system planning of the 1,000kW pilot plant, design and manufacturing of the reformer subsystem and the fuel cell subsystem, and design and manufacturing of the 250kW stacks for the 1,000kW plant. The 250kW stacks are developed on the basis of the results of the 100kW stack in 1993 and the following 25kW stack in 1994. In parallel to the stack development, Hitachi is also conducting researches for long endurance cells and stacks. In addition to the researches for anode, cathode, electrolyte, and electrolyte matrix, improvement of temperature distribution in stacks is investigated to extend the stack life. This paper describes the planning status of the 250kW stacks for the 1,000kW MCFC plant and the developing status of stack cooling method for longer life.

  6. Airborne Particulate Threat Assessment

    SciTech Connect

    Patrick Treado; Oksana Klueva; Jeffrey Beckstead

    2008-12-31

    Aerosol threat detection requires the ability to discern between threat agents and ambient background particulate matter (PM) encountered in the environment. To date, Raman imaging technology has been demonstrated as an effective strategy for the assessment of threat agents in the presence of specific, complex backgrounds. Expanding our understanding of the composition of ambient particulate matter background will improve the overall performance of Raman Chemical Imaging (RCI) detection strategies for the autonomous detection of airborne chemical and biological hazards. Improving RCI detection performance is strategic due to its potential to become a widely exploited detection approach by several U.S. government agencies. To improve the understanding of the ambient PM background with subsequent improvement in Raman threat detection capability, ChemImage undertook the Airborne Particulate Threat Assessment (APTA) Project in 2005-2008 through a collaborative effort with the National Energy Technology Laboratory (NETL), under cooperative agreement number DE-FC26-05NT42594. During Phase 1 of the program, a novel PM classification based on molecular composition was developed based on a comprehensive review of the scientific literature. In addition, testing protocols were developed for ambient PM characterization. A signature database was developed based on a variety of microanalytical techniques, including scanning electron microscopy, FT-IR microspectroscopy, optical microscopy, fluorescence and Raman chemical imaging techniques. An automated particle integrated collector and detector (APICD) prototype was developed for automated collection, deposition and detection of biothreat agents in background PM. During Phase 2 of the program, ChemImage continued to refine the understanding of ambient background composition. Additionally, ChemImage enhanced the APICD to provide improved autonomy, sensitivity and specificity. Deliverables included a Final Report detailing our

  7. Particulate deposition from turbulent parallel streams

    SciTech Connect

    Im, Kwan H.; Chung, Paul M.

    1981-02-01

    A theory is developed for particulate deposition rate on surfaces from turbulent gas streams. The three characteristic times, the particle equilibration time, the turbulent fluctuation time, and the particle residence time, control the deposition mode. The larger particles reach the wall across the laminar sublayer because of the momentum imparted to them by the turbulence velocity of the fluid. The smaller particles, on the other hand, diffuse to the wall by thermophoresis which depends on the temperature gradient. The computed results of the theory for pipe flow are compared with the available experimental data and satisfactory agreement is shown.

  8. Electrically heated particulate filter with reduced stress

    DOEpatents

    Gonze, Eugene V.

    2013-03-05

    A system comprises a particulate matter (PM) filter comprising an inlet for receiving exhaust gas. A zoned heater is arranged in the inlet and comprises a resistive heater comprising N zones, where N is an integer greater than one. Each of the N zones comprises M sub-zones, where M is an integer greater than one. A control module selectively activates one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones and deactivates others of the N zones.

  9. Inductively heated particulate matter filter regeneration control system

    SciTech Connect

    Gonze, Eugene V; Paratore Jr., Michael J; Kirby, Kevin W; Phelps, Amanda; Gregoire, Daniel J

    2012-10-23

    A system includes a particulate matter (PM) filter with an upstream end for receiving exhaust gas, a downstream end and zones. The system also includes a heating element. A control module selectively activates the heating element to inductively heat one of the zones.

  10. Ultra-dark graphene stack metamaterials

    NASA Astrophysics Data System (ADS)

    Chugh, Sunny; Man, Mengren; Chen, Zhihong; Webb, Kevin J.

    2015-02-01

    We present a fabrication method to achieve a graphene stack metamaterial, a periodic array of unit cells composed of graphene and a thin insulating spacer, that allows accumulation of the strong absorption from individual graphene sheets and low reflectivity from the stack. The complex sheet conductivity of graphene from experimental data models the measured power transmitted as a function of wavelength and number of periods in the stack. Simulated results based on the extracted graphene complex sheet conductivity for thicker stacks suggest that the graphene stack reflectivity and the per-unit-length absorption can be controlled to exceed the performance of competing light absorbers. Furthermore, the electrical properties of graphene coupled with the stack absorption characteristics provide for applications in optoelectronic devices.

  11. Organic content of particulate matter in turbine engine exhaust

    SciTech Connect

    Robertson, D.J.; Groth, R.H.; Blasko, T.J.

    1980-03-01

    Research report:Solid particulate matter, mainly carbon, emitted during fossil fuels combustion contains a variety of organic species adsorbed onto it. Studies were conducted to identify the organic compounds generated by a gas turbine engine. Total organics were determined by gas chromatography and flame ionization. Polynuclear aromatic hydrocarbons, phenols, and nitrosamines were present in samples collected from exhaust gases. (1 diagram, 4 references, 11 tables)

  12. Hydrogen Embrittlement And Stacking-Fault Energies

    NASA Technical Reports Server (NTRS)

    Parr, R. A.; Johnson, M. H.; Davis, J. H.; Oh, T. K.

    1988-01-01

    Embrittlement in Ni/Cu alloys appears related to stacking-fault porbabilities. Report describes attempt to show a correlation between stacking-fault energy of different Ni/Cu alloys and susceptibility to hydrogen embrittlement. Correlation could lead to more fundamental understanding and method of predicting susceptibility of given Ni/Cu alloy form stacking-fault energies calculated from X-ray diffraction measurements.

  13. Gas scrubbing device

    SciTech Connect

    Perry, G.A.

    1984-04-03

    An improved scrubbing device suitable for use in modular paint spray booths for extracting particulate matter entrained in a gas stream. The device includes an angularly inclined flood sheet adapted to be flooded with a continuous sheet of liquid and formed with a trough having a plurality of removable venturis disposed in spaced relationship through which the gas stream passes in a manner to effect atomization of the liquid flowing therethrough for scrubbing and extracting the particulate matter in the gas stream. Each venturi can be readily removed for periodic cleaning and service as well as replacement by alternative venturi configurations to modify the scrubbing characteristics thereof consistent with changes in the type and loading of particulate matter in the gas stream thereby achieving continuous optimum operating efficiency.

  14. Flexible interconnects for fuel cell stacks

    DOEpatents

    Lenz, David J.; Chung, Brandon W.; Pham, Ai Quoc

    2004-11-09

    An interconnect that facilitates electrical connection and mechanical support with minimal mechanical stress for fuel cell stacks. The interconnects are flexible and provide mechanically robust fuel cell stacks with higher stack performance at lower cost. The flexible interconnects replace the prior rigid rib interconnects with flexible "fingers" or contact pads which will accommodate the imperfect flatness of the ceramic fuel cells. Also, the mechanical stress of stacked fuel cells will be smaller due to the flexibility of the fingers. The interconnects can be one-sided or double-sided.

  15. Film stacking architecture for immersion lithography process

    NASA Astrophysics Data System (ADS)

    Goto, Tomohiro; Sanada, Masakazu; Miyagi, Tadashi; Shigemori, Kazuhito; Kanaoka, Masashi; Yasuda, Shuichi; Tamada, Osamu; Asai, Masaya

    2008-03-01

    In immersion lithography process, film stacking architecture will be necessary due to film peeling. However, the architecture will restrict lithographic area within a wafer due to top side EBR accuracy In this paper, we report an effective film stacking architecture that also allows maximum lithographic area. This study used a new bevel rinse system on RF3 for all materials to make suitable film stacking on the top side bevel. This evaluation showed that the new bevel rinse system allows the maximum lithographic area and a clean wafer edge. Patterning defects were improved with suitable film stacking.

  16. ooi: OpenStack OCCI interface

    NASA Astrophysics Data System (ADS)

    López García, Álvaro; Fernández del Castillo, Enol; Orviz Fernández, Pablo

    In this document we present an implementation of the Open Grid Forum's Open Cloud Computing Interface (OCCI) for OpenStack, namely ooi (Openstack occi interface, 2015) [1]. OCCI is an open standard for management tasks over cloud resources, focused on interoperability, portability and integration. ooi aims to implement this open interface for the OpenStack cloud middleware, promoting interoperability with other OCCI-enabled cloud management frameworks and infrastructures. ooi focuses on being non-invasive with a vanilla OpenStack installation, not tied to a particular OpenStack release version.

  17. Apparatus for particulate matter analysis

    DOEpatents

    Gundel, Lara A.; Apte, Michael G.; Hansen, Anthony D.; Black, Douglas R.

    2007-01-30

    The apparatus described herein is a miniaturized system for particle exposure assessment (MSPEA) for the quantitative measurement and qualitative identification of particulate content in gases. The present invention utilizes a quartz crystal microbalance (QCM) or other mass-sensitive temperature compensated acoustic wave resonator for mass measurement. Detectors and probes and light sources are used in combination for the qualitative determination of particulate matter.

  18. Surface and Interface Chemistry for Gate Stacks on Silicon

    NASA Astrophysics Data System (ADS)

    Frank, M. M.; Chabal, Y. J.

    This chapter addresses the fundamental silicon surface science associated with the continued progress of nanoelectronics along the path prescribed by Moore's law. Focus is on hydrogen passivation layers and on ultrathin oxide films encountered during silicon cleaning and gate stack formation in the fabrication of metal-oxide-semiconductor field-effect transistors (MOSFETs). Three main topics are addressed. (i) First, the current practices and understanding of silicon cleaning in aqueous solutions are reviewed, including oxidizing chemistries and cleans leading to a hydrogen passivation layer. The dependence of the final surface termination and morphology/roughness on reactant choice and pH and the influence of impurities such as dissolved oxygen or metal ions are discussed. (ii) Next, the stability of hydrogen-terminated silicon in oxidizing liquid and gas phase environments is considered. In particular, the remarkable stability of hydrogen-terminated silicon surface in pure water vapor is discussed in the context of atomic layer deposition (ALD) of high-permittivity (high-k) gate dielectrics where water is often used as an oxygen precursor. Evidence is also provided for co-operative action between oxygen and water vapor that accelerates surface oxidation in humid air. (iii) Finally, the fabrication of hafnium-, zirconium- and aluminum-based high-k gate stacks is described, focusing on the continued importance of the silicon/silicon oxide interface. This includes a review of silicon surface preparation by wet or gas phase processing and its impact on high-k nucleation during ALD growth, and the consideration of gate stack capacitance and carrier mobility. In conclusion, two issues are highlighted: the impact of oxygen vacancies on the electrical characteristics of high-k MOS devices, and the way alloyed metal ions (such as Al in Hf-based gate stacks) in contact with the interfacial silicon oxide layer can be used to control flatband and threshold voltages.

  19. Debuncher Cooling Limitations to Stacking

    SciTech Connect

    Halling, Mike

    1991-08-13

    During the January studies period we performed studies to determine the effect that debuncher cooling has on the stacking rate. Two different sets of measurements were made separated by about a week. Most measurements reported here are in PBAR log 16, page 243-247. These measurements were made by changing the accelerator timeline to give about 6 seconds between 29's, and then gating the cooling systems to simulate reduced cycle times. For the measurement of the momentum cooling effectiveness the gating switches could not be made to work, so the timeline was changed for each measurement. The cooling power of all three systems was about 800 watts for the tests reported here. We now regularly run at 1200 watts per system.

  20. Stacked subsea templates accelerate deepwater development

    SciTech Connect

    Ramsey, J.F.; Blincow, R.M.; Pickard, R.D. )

    1991-10-21

    This paper reports on a deepwater project that can be brought on-line more quickly because of stackable drilling and production templates. Historically, one of the primary barriers to the economic development of deepwater reserves has been the long lead time from discovery to first production. Typically, production facilities must be built and often installed before development wells are drilled. The use of three-slot drilling templates allows development drilling to proceed while the production templates, Christmas trees, flow lines, and production platform are constructed. Thus, the time from initial investment to first revenue reduced. Enserch Exploration Inc., along with partners Petrofina Delaware Inc. and AGIP Petroleum, is using a piggy-back or transportable stacked template system to develop deepwater gas reserves in Mississippi Canyon Block 441, approximately 50 miles south of Grand Isle, La. The discovery is located in 1,410-1,520 ft of water. The Louisiana Offshore Oil Port (LOOP) safety fairway running north to south covers the eastern three fourths of Mississippi Canyon Block 441 and rules out surface production facilities over the well locations.

  1. Particulate erosion mechanisms

    NASA Technical Reports Server (NTRS)

    Veerabhadrarao, P.; Buckley, D. H.

    1983-01-01

    Particulate damage and erosion of ductile metals are today plaguing design and field engineers in diverse fields of engineering and technology. It was found that too many models and theories were proposed leading to much speculation from debris analysis and failure mechanism postulations. Most theories of solid particle erosion are based on material removal models which do not fully represent the actual physical processes of material removal. The various mechanisms proposed thus far are: melting, low-cycle fatigue, extrusion, delamination, shear localization, adhesive material transfer, etc. The experimental data on different materials highlighting the observed failure modes of the deformation and cutting wear processes using optical and scanning electron microscopy are presented. The most important mechanisms proved from the experimental observations of the specimens exposed to both spherical and angular particles are addressed, and the validity of the earlier theories discussed. Both the initial stages of damage and advanced stages of erosion were studied to gain a fundamental understanding of the process.

  2. Pressure driven particulate flows

    SciTech Connect

    Ingher, M.S.; Mondy, L.A.

    1996-03-01

    Numerical simulations of pressure-driven particulate Stokes flows are performed in cylindrical and rectangular conduits using a parallel boundary element code. Spherical particles are randomly placed in the conduits and a pressure drop between the ends of the conduits is imposed by the boundary conditions to induce a Poiseuille-like flow field. The instantaneous velocities of the particles are then calculated, as well as the additional pressure drop necessary to maintain a constant flow rate. Because the results depend on the spatial distribution of the particles, several random configurations of particles are examined for each case. Depending on two different interpretations of the numerical results, the solid phase can be represented as either leading or lagging the fluid phase. Both of the analyses and interpretations are presented.

  3. A bundled-stack discotic columnar liquid crystalline phase with inter-stack electronic coupling

    DOE PAGES

    Wang, Bin; Sun, Runkun; Günbaş, Duygu D.; ...

    2015-06-15

    The first compound proving to be capable of forming a bundled-stack discotic columnar liquid crystalline (BSDCLC) phase was designed and synthesized. Finally, the unique perylene anhydride inter-stack interaction was found to be the key to the formation of the BSDCLC structure and inter-stack electronic coupling (ISEC).

  4. Particulate distribution function evolution for ejecta transport

    SciTech Connect

    Hammerberg, James Edward; Plohr, Bradley J

    2010-01-01

    The time evolution of the ejecta distribution function in a gas is discussed in the context of the recent experiments of W. Buttler and M. Zellner for well characterized Sn surfaces. Evolution equations are derived for the particulate distribution function when the dominant gas-particle interaction in is particulate drag. In the approximation of separability of the distribution function in velocity and size, the solution for the time dependent distribution function is a Fredholm integral equation of the first kind whose kernel is expressible in terms of the vacuum time dependent velocity distribution function measured with piezo probes or Asay foils. The solution of this equation in principle gives the size distribution function. We discuss the solution of this equation and the results of the Buttler - Zellner experiments. These suggest that correlations in velocity and size are necessary for a complete description of the transport dala. The solutions presented also represent an analytic test problem for the calculated distribution function in ejecta transport implementations.

  5. EFFECT OF GEOMETRY AND OPERATING PARAMETERS ON SIMULATED SOFC STACK TEMPERATURE UNIFORMITY

    SciTech Connect

    Koeppel, Brian J.; Lai, Canhai; Khaleel, Mohammad A.

    2011-08-10

    A uniform temperature field is desirable in the solid oxide fuel cell stack to avoid local hot regions that contribute to material degradation, thermal stresses, and differences in electrochemical performance. Various geometric and operational design changes were simulated by numerical modeling of co-flow and counter-flow multi-cell stacks, and the effects on stack maximum temperature, stack temperature difference, and maximum cell temperature difference were characterized. The results showed that 40-60% on-cell steam reforming of methane and a reduced reforming rate of 25-50% of the nominal rate was beneficial for a more uniform temperature field. Fuel exhaust recycling up to 30% was shown to be advantageous for reforming fuels and co-flow stacks with hydrogen fuel, but counter-flow stacks with hydrogen fuel showed higher temperature differences. Cells with large aspect ratios showed a more uniform temperature response due to either the strong influence of the inlet gas temperatures or the greater thermal exchange with the furnace boundary condition. Improved lateral heat spreading with thicker interconnects was demonstrated, but greater improvements towards a uniform thermal field for the same amount of interconnect mass could be achieved using thicker heat spreader plates appropriately distributed along the stack height.

  6. Effective Stack Design in Air Pollution Control.

    ERIC Educational Resources Information Center

    Clarke, John H.

    1968-01-01

    Stack design problems fall into two general caterories--(1) those of building re-entry, and (2) those of general area pollution. Extensive research has developed adequate information, available in the literature, to permit effective stack design. A major roadblock to effective design has been the strong belief by architects and engineers that high…

  7. Magnetic characterization of airborne particulates

    NASA Astrophysics Data System (ADS)

    Kim, W.; Doh, S.; Yu, Y.

    2010-12-01

    Burning fossil fuels from vehicles, domestics, industries and power plants in the large urban or industrial areas emit significant quantity of anthropogenic particulates which become a potential threat to human health. Here, we present temporal variability of particulate pollution associated with compositional differences, using magnetic measurements and electron microscopic observations. Six different grain-sizes of airborne particulates have been collected by filtering from 10 precipitation events in Seoul, Korea from February 2009 to June 2009. Magnetic concentration proxies show relatively better (R2 >0.6) and poorer correlations (R2 <0.3) with the masses of samples filtered by >0.45 μm and <0.45 μm sizes, respectively, suggesting the usefulness of magnetic characterization for the >0.45 μm particulates. Temporally, magnetic concentrations are higher in the cold season than the warm season. In particular, a significant increase of magnetic concentration is observed in 3 μm and 1 μm filters after the Chinese wind-blown dust events, indicating additional influx of fine-grained anthropogenic particulates into Seoul. Microscopic observations identify that increase of magnetic concentration is highly linked with the frequent occurrence of combustion derived particulates (i.e., carbon and/or sulfur mixed particles) than natural alumino-silicates. Overall, the present study demonstrates that magnetic measurements efficiently reflect the concentration of particulates produced from fossil-fuel combustion among the airborne particles from various sources.

  8. Status of MCFC stack technology at IHI

    SciTech Connect

    Hosaka, M.; Morita, T.; Matsuyama, T.; Otsubo, M.

    1996-12-31

    The molten carbonate fuel cell (MCFC) is a promising option for highly efficient power generation possible to enlarge. IHI has been studying parallel flow MCFC stacks with internal manifolds that have a large electrode area of 1m{sup 2}. IHI will make two 250 kW stacks for MW plant, and has begun to make cell components for the plant. To improve the stability of stack, soft corrugated plate used in the separator has been developed, and a way of gathering current from stacks has been studied. The DC output potential of the plant being very high, the design of electric insulation will be very important. A 20 kW short stack test was conducted in 1995 FY to certificate some of the improvements and components of the MW plant. These activities are presented below.

  9. Device for equalizing molten electrolyte content in a fuel cell stack

    DOEpatents

    Smith, J.L.

    1985-12-23

    A device for equalizing the molten electrolyte content throughout the height of a fuel cell stack is disclosed. The device includes a passageway for electrolyte return with electrolyte wettable wicking material in the opposite end portions of the passageway. One end portion is disposed near the upper, negative end of the stack where electrolyte flooding occurs. The second end portion is placed near the lower, positive end of the stack where electrolyte is depleted. Heating means are provided at the upper portion of the passageway to increase electrolyte vapor pressure in the upper wicking material. The vapor is condensed in the lower passageway portion and conducted as molten electrolyte in the lower wick to the positive end face of the stack. An inlet is provided to inject a modifying gas into the passageway and thereby control the rate of electrolyte return.

  10. Device for equalizing molten electrolyte content in a fuel cell stack

    DOEpatents

    Smith, James L.

    1987-01-01

    A device for equalizing the molten electrolyte content throughout the height of a fuel cell stack is disclosed. The device includes a passageway for electrolyte return with electrolyte wettable wicking material in the opposite end portions of the passageway. One end portion is disposed near the upper, negative end of the stack where electrolyte flooding occurs. The second end portion is placed near the lower, positive end of the stack where electrolyte is depleted. Heating means are provided at the upper portion of the passageway to increase electrolyte vapor pressure in the upper wicking material. The vapor is condensed in the lower passageway portion and conducted as molten electrolyte in the lower wick to the positive end face of the stack. An inlet is provided to inject a modifying gas into the passageway and thereby control the rate of electrolyte return.

  11. Dynamic behaviour of SOFC short stacks

    NASA Astrophysics Data System (ADS)

    Molinelli, Michele; Larrain, Diego; Autissier, Nordahl; Ihringer, Raphaël; Sfeir, Joseph; Badel, Nicolas; Bucheli, Olivier; Van herle, Jan

    Electrical output behaviour obtained on solid oxide fuel cell stacks, based on planar anode supported cells (50 or 100 cm 2 active area) and metallic interconnects, is reported. Stacks (1-12 cells) have been operated with cathode air and anode hydrogen flows between 750 and 800 °C operating temperature. At first polarisation, an activation phase (increase in power density) is typically observed, ascribed to the cathode but not clarified. Activation may extend over days or weeks. The materials are fairly resistant to thermal cycling. A 1-cell stack cycled five times in 4 days at heating/cooling rates of 100-300 K h -1, showed no accelerated degradation. In a 5-cell stack, open circuit voltage (OCV) of all cells remained constant after three full cycles (800-25 °C). Power output is little affected by air flow but markedly influenced by small fuel flow variation. Fuel utilisation reached 88% in one 5-cell stack test. Performance homogeneity between cells lay at ±4-8% for three different 5- or 6-cell stacks, but was poor for a 12-cell stack with respect to the border cells. Degradation of a 1-cell stack operated for 5500 h showed clear dependence on operating conditions (cell voltage, fuel conversion), believed to be related to anode reoxidation (Ni). A 6-cell stack (50 cm 2 cells) delivering 100 W el at 790 °C (1 kW el L -1 or 0.34 W cm -2) went through a fuel supply interruption and a thermal cycle, with one out of the six cells slightly underperforming after these events. This cell was eventually responsible (hot spot) for stack failure.

  12. ADVANCED HYBRID PARTICULATE COLLECTOR

    SciTech Connect

    Ye Zhuang; Stanley J. Miller; Michelle R. Olderbak; Rich Gebert

    2001-12-01

    A new concept in particulate control, called an advanced hybrid particulate collector (AHPC), is being developed under funding from the U.S. Department of Energy. The AHPC combines the best features of electrostatic precipitators (ESPs) and baghouses in an entirely novel manner. The AHPC concept combines fabric filtration and electrostatic precipitation in the same housing, providing major synergism between the two methods, both in the particulate collection step and in transfer of dust to the hopper. The AHPC provides ultrahigh collection efficiency, overcoming the problem of excessive fine-particle emissions with conventional ESPs, and solves the problem of reentrainment and re-collection of dust in conventional baghouses. Phase I of the development effort consisted of design, construction, and testing of a 5.7-m{sup 3}/min (200-acfm) working AHPC model. Results from both 8-hr parametric tests and 100-hr proof-of-concept tests with two different coals demonstrated excellent operability and greater than 99.99% fine-particle collection efficiency. Since all of the developmental goals of Phase I were met, the approach was scaled up in Phase II to a size of 255 m{sup 3}/min (9000 acfm) (equivalent in size to 2.5 MW) and was installed on a slipstream at the Big Stone Power Plant. For Phase II, the AHPC at Big Stone Power Plant was operated continuously from late July 1999 until mid-December 1999. The Phase II results were highly successful in that ultrahigh particle collection efficiency was achieved, pressure drop was well controlled, and system operability was excellent. For Phase III, the AHPC was modified into a more compact configuration, and components were installed that were closer to what would be used in a full-scale commercial design. The modified AHPC was operated from April to July 2000. While operational results were acceptable during this time, inspection of bags in the summer of 2000 revealed some membrane damage to the fabric that appeared to be

  13. Development of small polymer electrolyte fuel cell stacks

    SciTech Connect

    Paganin, V.A.; Ticianelli, E.A.; Gonzalez, E.R.

    1996-12-31

    The polymer electrolyte fuel cell (PEFC) has been one of the most studied fuel cell systems, because of several advantages for transportation applications. Research involve fundamental aspects related to the water transport and the fuel cell reactions, the practical aspects related to the optimization of the structure and operational conditions of gas diffusion electrodes, and technological aspects related to water management and the engineering of operational sized fuel cell modules. In many of these works it is observed that very satisfactory results regarding the performance of low catalyst loading electrodes (0.15 to 0.4 mg Pt/cm{sup 2}) have been obtained in single cells. However, the use of such electrodes is not yet being considered for building fuel cell stacks and, although not usually mentioned, fuel cell modules are assembled employing electrodes presenting catalyst loadings in the range of 2 to 4 mgPt cm{sup -2}. In this work the results on the research and development of small polymer electrolyte fuel cell stacks employing low catalyst loading electrodes are described. The systems include the assembly of single cells, 6-cell and 21-cell modules. Testing of the stacks was conducted in a specially designed test station employing non-pressurized H{sub 2}/O{sub 2} reactants and measuring the individual and the overall cell voltage versus current characteristics under several operational conditions for the system.

  14. Method and apparatus for transport, introduction, atomization and excitation of emission spectrum for quantitative analysis of high temperature gas sample streams containing vapor and particulates without degradation of sample stream temperature

    DOEpatents

    Eckels, David E.; Hass, William J.

    1989-05-30

    A sample transport, sample introduction, and flame excitation system for spectrometric analysis of high temperature gas streams which eliminates degradation of the sample stream by condensation losses.

  15. Evaluation of distributed gas cooling of pressurized PAFC for utility power generation

    NASA Technical Reports Server (NTRS)

    Farooque, M.; Hooper, M.; Maru, H.

    1981-01-01

    A proof-of-concept test for a gas-cooled pressurized phosphoric acid fuel cell is described. After initial feasibility studies in short stacks, two 10 kW stacks are tested. Progress includes: (1) completion of design of the test stations with a recirculating gas cooling loop; (2) atmospheric testing of the baseline stack.

  16. Electrically heated particulate filter restart strategy

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

    2011-07-12

    A control system that controls regeneration of a particulate filter is provided. The system generally includes a propagation module that estimates a propagation status of combustion of particulate matter in the particulate filter. A regeneration module controls current to the particulate filter to re-initiate regeneration based on the propagation status.

  17. Mechanisms of accelerated degradation in the front cells of PEMFC stacks and some mitigation strategies

    NASA Astrophysics Data System (ADS)

    Li, Pengcheng; Pei, Pucheng; He, Yongling; Yuan, Xing; Chao, Pengxiang; Wang, Xizhong

    2013-11-01

    The accelerated degradation in the front cells of a polymer electrolyte membrane fuel cell(PEMFC) stack seriously reduces the reliability and durability of the whole stack. Most researches only focus on the size and configuration of the gas intake manifold, which may lead to the maldistribution of flow and pressure. In order to find out the mechanisms of the accelerated degradation in the front cells, an extensive program of experimental and simulation work is initiated and the results are reported. It is found that after long-term lifetime tests the accelerated degradation in the front cells occurs in all three fuel cell stacks with different flow-fields under the U-type feed configuration. Compared with the rear cells of the stack, the voltage of the front cells is much lower at the same current densities and the membrane electrode assembly(MEA) has smaller active area, more catalyst particle agglomeration and higher ohmic impedance. For further investigation, a series of three dimensional isothermal numerical models are built to investigate the degradation mechanisms based on the experimental data. The simulation results reveal that the dry working condition of the membrane and the effect of high-speed gas scouring the MEA are the main causes of the accelerated degradation in the front cells of a PEM fuel cell stack under the U-type feed configuration. Several mitigation strategies that would mitigate these phenomena are presented: removing cells that have failed and replacing them with those of the same aging condition as the average of the stack; choosing a Z-type feed pattern instead of a U-type one; putting several air flow-field plates without MEA in the front of the stack; or exchanging the gas inlet and outlet alternately at a certain interval. This paper specifies the causes of the accelerated degradation in the front cells and provides the mitigation strategies.

  18. [Analysis on Mechanism of Rainout Carried by Wet Stack of Thermal Power Plant].

    PubMed

    Ouyang, Li-hua; Zhuang, Ye; Liu, Ke-wei; Chen, Zhen-yu; Gu, Peng

    2015-06-01

    Rainout from wet-stack took placed in many thermal power plants with WFGD system. Research on causes of the rainout is important to solve the problem. The objective of this research is to analyze the mechanism of rainout. Field study was performed to collect experimental data in one thermal power plant, including the amount of desulfurization slurry carried by wet flue gas, liquor condensate from wet duct, and droplets from the wet stack. Source apportionment analysis was carried out based on physical and chemical data of liquid sample and solid sample. The result showed that mist eliminator operated well, which met the performance guarantee value. But the total amount of desulfurization slurry in flue gas and the sulfate concentration in liquid condensate discharge from the wet duct/stack increased. The liquid condensate accumulated in the wet duct/stack led to liquid re-entrainment. In conclusion, the rainout in this power plant was caused by the short of wet ductwork or liquid discharge system, the droplets caused by re-entrainment carried by the saturated gas released from the stack. The main undissolved components of the rainout were composite carbonate and aluminosilicate. Although ash concentration in this WFGD met the regulation criteria, source apportionment analysis showed that fly ash contributed to rainout was accounted for 60%. This percentage value was same as the data of solid particles in the condensate. It is important to optimize the wet ductwork, wet stack liner, liquid collectors and drainage. Avoiding the accumulation from saturated vapor thermal condensation is an effective way to solve the wet stack rainout.

  19. Measurement of vehicle particulate emissions.

    PubMed Central

    Beltzer, M

    1975-01-01

    A constant volume sampler (CVS) compatible auto exhaust particulate sampling system has been built which samples exhaust isokinetically at constant temperature. This system yields internally consistent results and is capable of frequent and convenient operation. PMID:50931

  20. Elevated exhaust temperature, zoned, electrically-heated particulate matter filter

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Bhatia, Garima [Bangalore, IN

    2012-04-17

    A system includes an electrical heater and a particulate matter (PM) filter that is arranged one of adjacent to and in contact with the electrical heater. A control module selectively increases an exhaust gas temperature of an engine to a first temperature and that initiates regeneration of the PM filter using the electrical heater while the exhaust gas temperature is above the first temperature. The first temperature is greater than a maximum exhaust gas temperature at the PM filter during non-regeneration operation and is less than an oxidation temperature of the PM.

  1. Passive stacks in a multifamily housing project

    SciTech Connect

    Saum, D.

    1995-12-31

    The Summerfield multi-family, 1242 unit housing project that has been under construction since 1993 in Prince Georges County Maryland near Washington, DC suggests that passive stacks provides significant radon mitigation in multi-family construction. Random radon tests in these buildings indicate an average indoor ground floor concentration of 0.3 pCi/L with the stacks open, and 1.3 pCi/L with the stacks sealed. These buildings were built with post-tension slabs which should be more airtight than conventional floating slabs, and measurements show that the pressure field extension in these slabs in very good.

  2. Dynamical stability of slip-stacking particles

    SciTech Connect

    Eldred, Jeffrey; Zwaska, Robert

    2014-09-01

    We study the stability of particles in slip-stacking configuration, used to nearly double proton beam intensity at Fermilab. We introduce universal area factors to calculate the available phase space area for any set of beam parameters without individual simulation. We find perturbative solutions for stable particle trajectories. We establish Booster beam quality requirements to achieve 97% slip-stacking efficiency. We show that slip-stacking dynamics directly correspond to the driven pendulum and to the system of two standing-wave traps moving with respect to each other.

  3. Electrical diesel particulate filter (DPF) regeneration

    DOEpatents

    Gonze, Eugene V; Ament, Frank

    2013-12-31

    An exhaust system that processes exhaust generated by an engine includes a diesel particulate filter (DPF) that is disposed downstream of the engine and that filters particulates from the exhaust. An electrical heater is disposed upstream of the DPF and selectively heats the exhaust to initiate combustion of the particulates within the exhaust as it passes therethrough. Heat generated by combustion of the particulates induces combustion of particulates within the DPF.

  4. Modeling the Air Flow in the 3410 Building Filtered Exhaust Stack System

    SciTech Connect

    Recknagle, Kurtis P.; Barnett, J. Matthew; Suffield, Sarah R.

    2013-01-23

    Additional ventilation capacity has been designed for the 3410 Building filtered exhaust stack system. The updated system will increase the number of fans from two to three and will include ductwork to incorporate the new fan into the existing stack. Stack operations will involve running various two-fan combinations at any given time. The air monitoring system of the existing two-fan stack was previously found to be in compliance with the ANSI/HPS N13.1-1999 standard, however it is not known if the modified (three-fan) system will comply. Subsequently, a full-scale three-dimensional (3-D) computational fluid dynamics (CFD) model of the modified stack system has been created to examine the sampling location for compliance with the standard. The CFD modeling results show good agreement with testing data collected from the existing 3410 Building stack and suggest that velocity uniformity and flow angles will remain well within acceptance criteria when the third fan and associated ductwork is installed. This includes two-fan flow rates up to 31,840 cfm for any of the two-fan combinations. For simulation cases in which tracer gas and particles are introduced in the main duct, the model predicts that both particle and tracer gas coefficients of variance (COVs) may be larger than the acceptable 20 percent criterion of the ANSI/HPS N13.1-1999 standard for each of the two-fan, 31,840 cfm combinations. Simulations in which the tracers are introduced near the fans result in improved, though marginally acceptable, COV values for the tracers. Due to the remaining uncertainty that the stack will qualify with the addition of the third fan and high flow rates, a stationary air blender from Blender Products, Inc. is considered for inclusion in the stack system. A model of the air blender has been developed and incorporated into the CFD model. Simulation results from the CFD model that includes the air blender show striking improvements in tracer gas mixing and tracer particle

  5. Stacked vapor fed amtec modules

    DOEpatents

    Sievers, Robert K.

    1989-01-01

    The present invention pertains to a stacked AMTEC module. The invention includes a tubular member which has an interior. The member is comprised of a ion conductor that substantially conducts ions relative to electrons, preferably a beta"-alumina solid electrolyte, positioned about the interior. A porous electrode for conducting electrons and allowing sodium ions to pass therethrough, and wherein electrons and sodium ions recombine to form sodium is positioned about the beta"-alumina solid electrolyte. The electrode is operated at a temperature and a pressure that allows the recombined sodium to vaporize. Additionally, an outer current collector grid for distributing electrons throughout the porous electrode is positioned about and contacts the porous electrode. Also included in the invention is transporting means for transporting liquid sodium to the beta"-alumina solid electrolyte of the tubular member. A transition piece is positioned about the interior of the member and contacts the transporting means. The transition piece divides the member into a first cell and a second cell such that each first and second cell has a beta"-alumina solid electrolyte, a first and second porous electrode and a grid. The transition piece conducts electrons from the interior of the tubular member. There is supply means for supplying sodium to the transporting means. Preferably the supply means is a shell which surrounds the tubular member and is operated at a temperature such that the vaporized sodium condenses thereon. Returning means for returning the condensed sodium from the shell to the transporting means provides a continuous supply of liquid sodium to the transporting means. Also, there are first conducting means for conducting electric current from the transition piece which extends through the shell, and second conducting means for conducting electric current to the grid of the first cell which extends through the shell.

  6. Near-Earth Asteroid Stack - Mission Animation

    NASA Video Gallery

    A possible stack configuration - a deep space habitat, the Orion Multi-Purpose Crew Vehicle and Space Exploration Vehicle - approaches a near-Earth asteroid. During a mission that could take months...

  7. Characterization of Piezoelectric Stacks for Space Applications

    NASA Technical Reports Server (NTRS)

    Sherrit, Stewart; Jones, Christopher; Aldrich, Jack; Blodget, Chad; Bao, Xiaoqi; Badescu, Mircea; Bar-Cohen, Yoseph

    2008-01-01

    Future NASA missions are increasingly seeking to actuate mechanisms to precision levels in the nanometer range and below. Co-fired multilayer piezoelectric stacks offer the required actuation precision that is needed for such mechanisms. To obtain performance statistics and determine reliability for extended use, sets of commercial PZT stacks were tested in various AC and DC conditions at both nominal and high temperatures and voltages. In order to study the lifetime performance of these stacks, five actuators were driven sinusoidally for up to ten billion cycles. An automated data acquisition system was developed and implemented to monitor each stack's electrical current and voltage waveforms over the life of the test. As part of the monitoring tests, the displacement, impedance, capacitance and leakage current were measured to assess the operation degradation. This paper presents some of the results of this effort.

  8. 40 CFR 61.33 - Stack sampling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.33 Stack... Administrator. (d) All samples shall be analyzed and beryllium emissions shall be determined within 30...

  9. 40 CFR 61.33 - Stack sampling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.33 Stack... results reported to the Administrator. (d) All samples shall be analyzed and beryllium emissions shall...

  10. 40 CFR 61.33 - Stack sampling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.33 Stack... Administrator. (d) All samples shall be analyzed and beryllium emissions shall be determined within 30...

  11. 40 CFR 61.33 - Stack sampling.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.33 Stack... Administrator. (d) All samples shall be analyzed and beryllium emissions shall be determined within 30...

  12. 40 CFR 61.33 - Stack sampling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.33 Stack... Administrator. (d) All samples shall be analyzed and beryllium emissions shall be determined within 30...

  13. Wearable solar cells by stacking textile electrodes.

    PubMed

    Pan, Shaowu; Yang, Zhibin; Chen, Peining; Deng, Jue; Li, Houpu; Peng, Huisheng

    2014-06-10

    A new and general method to produce flexible, wearable dye-sensitized solar cell (DSC) textiles by the stacking of two textile electrodes has been developed. A metal-textile electrode that was made from micrometer-sized metal wires was used as a working electrode, while the textile counter electrode was woven from highly aligned carbon nanotube fibers with high mechanical strengths and electrical conductivities. The resulting DSC textile exhibited a high energy conversion efficiency that was well maintained under bending. Compared with the woven DSC textiles that are based on wire-shaped devices, this stacked DSC textile unexpectedly exhibited a unique deformation from a rectangle to a parallelogram, which is highly desired in portable electronics. This lightweight and wearable stacked DSC textile is superior to conventional planar DSCs because the energy conversion efficiency of the stacked DSC textile was independent of the angle of incident light.

  14. Contemporary sample stacking in analytical electrophoresis.

    PubMed

    Šlampová, Andrea; Malá, Zdena; Pantůčková, Pavla; Gebauer, Petr; Boček, Petr

    2013-01-01

    Sample stacking is a term denoting a multifarious class of methods and their names that are used daily in CE for online concentration of diluted samples to enhance separation efficiency and sensitivity of analyses. The essence of these methods is that analytes present at low concentrations in a large injected sample zone are concentrated into a short and sharp zone (stack) in the separation capillary. Then the stacked analytes are separated and detected. Regardless of the diversity of the stacking electromigration methods, one can distinguish four main principles that form the bases of nearly all of them: (i) Kohlrausch adjustment of concentrations, (ii) pH step, (iii) micellar methods, and (iv) transient ITP. This contribution is a continuation of our previous reviews on the topic and brings an overview of papers published during 2010-2012 and relevant to the mentioned principles (except the last one which is covered by another review in this issue).

  15. 40 CFR 63.307 - Standards for bypass/bleeder stacks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... install a bypass/bleeder stack flare system that is capable of controlling 120 percent of the normal gas... system or the alternative control device as described in paragraph (d) of this section. (3) The owner or operator of a brownfield coke oven battery or a padup rebuild shall install such a flare system...

  16. Assaying baseline status of particulate laden polyaromatic hydrocarbon for a grass root level industrial project

    SciTech Connect

    Pandya, G.H.; Chatterjee, N.; Singh, R.; Kashyap, S.; Saheb, S.P.; Wate, S.R.

    2009-02-15

    A study of particulate laden polyaromatic hydrocarbon was conducted at 13 selected locations in a 10 km radial distance of a proposed site for a grass root level industry. Suspended particulate matter samples were continuously monitored for 24 h over a period of 3 months. The Polyaromatic Hydrocarbons (PAHs) were extracted from the particulate samples and analysed using Gas Chromatograph-Mass Spectrometer. Limit of Quantification was also established for individual PAHs. Coal combustion and traffic emission were the major contributors for PAHs in the region. The relative contribution of 2, 3, 4, 5, and 6 ring PAHs in particulates of different sampling sites was also investigated and it is observed that 4 ring (29.76%) and 5 ring (29.06%) compounds are prominent in the particulates measured in the region.

  17. Modified three-dimensional percolation simulation of char fragmentation and particulate formation

    NASA Astrophysics Data System (ADS)

    Wang, Huashan; Li, Huiyi; Chen, Qingjie; Gao, Jianmin; Wang, Chunsheng

    2017-02-01

    The current numerical calculation of particulate formation during char combustion mainly adopts the two-dimensional model. In this paper, based on the introduction of the concept of diffusion depth, the char combustion is simulated with a three-dimensional model. The modified model can simulate the actual situation that the reactant gas dose not diffuse into the char completely. The approach to realize the combustion process of char in chemical controlled zone (zone I) and transitional controlled zone (zone II) is given, and the results are compared with those in the diffusion controlled zone (zone III). The characteristic impact of initial porosity and mineral content on particulate formation in different zones is analyzed through the simulation and comparison. It can be seen from the results that the diffusion depth do put some limits on char fragmentation and mass distribution of ash particulates, which provides theoretical basis for the further study of particulate formation during char combustion and the reduction of particulate emission.

  18. Measuring Structural Parameters Through Stacking Galaxy Images

    NASA Astrophysics Data System (ADS)

    Li, Yubin; Zheng, Xian Zhong; Gu, Qiu-Sheng; Wang, Yi-Peng; Wen, Zhang Zheng; Guo, Kexin; An, Fang Xia

    2016-12-01

    It remains challenging to detect the low surface brightness structures of faint high-z galaxies, which are key to understanding the structural evolution of galaxies. The technique of image stacking allows us to measure the averaged light profile beneath the detection limit and probe the extended structure of a group of galaxies. We carry out simulations to examine the recovery of the averaged surface brightness profile through stacking model Hubble Space Telescope/Advanced Camera for Surveys images of a set of galaxies as functions of the Sérsic index (n), effective radius (R e) and axis ratio (AR). The Sérsic profile best fitting the radial profile of the stacked image is taken as the recovered profile, in comparison with the intrinsic mean profile of the model galaxies. Our results show that, in general, the structural parameters of the mean profile can be properly determined through stacking, though systematic biases need to be corrected when spreads of R e and AR are counted. We find that the Sérsic index is slightly overestimated and R e is underestimated at {AR}\\lt 0.5 because the stacked image appears to be more compact due to the presence of inclined galaxies; the spread of R e biases the stacked profile to have a higher Sérsic index. We stress that the measurements of structural parameters through stacking should take these biases into account. We estimate the biases in the recovered structural parameters from stacks of galaxies when the samples have distributions of {R}{{e}}, AR and n seen in local galaxies.

  19. Stacking fault energy in some single crystals

    NASA Astrophysics Data System (ADS)

    Vora, Aditya M.

    2012-06-01

    The stacking fault energy of single crystals has been reported using the peak shift method. Presently studied all single crystals are grown by using a direct vapor transport (DVT) technique in the laboratory. The structural characterizations of these crystals are made by XRD. Considerable variations are shown in deformation (α) and growth (β) probabilities in single crystals due to off-stoichiometry, which possesses the stacking fault in the single crystal.

  20. Method and apparatus for transport, introduction, atomization and excitation of emission spectrum for quantitative analysis of high temperature gas sample streams containing vapor and particulates without degradation of sample stream temperature

    SciTech Connect

    Eckels, D.E.; Hass, W.J.

    1989-05-30

    A sample transport, sample introduction, and flame excitation system is described for spectrometric analysis of high temperature gas streams which eliminates degradation of the sample stream by condensation losses. 4 figs.

  1. Analyses of Large Coal-Based SOFCs for High Power Stack Block Development

    SciTech Connect

    Recknagle, Kurtis P; Koeppel, Brian J

    2010-10-01

    This report summarizes the numerical modeling and analytical efforts for SOFC stack development performed for the coal-based SOFC program. The stack modeling activities began in 2004, but this report focuses on the most relevant results obtained since August 2008. This includes the latter half of Phase-I and all of Phase-II activities under technical guidance of VPS and FCE. The models developed to predict the thermal-flow-electrochemical behaviors and thermal-mechanical responses of generic planar stacks and towers are described. The effects of cell geometry, fuel gas composition, on-cell reforming, operating conditions, cell performance, seal leak, voltage degradation, boundary conditions, and stack height are studied. The modeling activities to evaluate and achieve technical targets for large stack blocks are described, and results from the latest thermal-fluid-electrochemical and structural models are summarized. Modeling results for stack modifications such as scale-up and component thickness reduction to realize cost reduction are presented. Supporting modeling activities in the areas of cell fabrication and loss of contact are also described.

  2. Solid oxide fuel cell generator with removable modular fuel cell stack configurations

    DOEpatents

    Gillett, James E.; Dederer, Jeffrey T.; Zafred, Paolo R.; Collie, Jeffrey C.

    1998-01-01

    A high temperature solid oxide fuel cell generator produces electrical power from oxidation of hydrocarbon fuel gases such as natural gas, or conditioned fuel gases, such as carbon monoxide or hydrogen, with oxidant gases, such as air or oxygen. This electrochemical reaction occurs in a plurality of electrically connected solid oxide fuel cells bundled and arrayed in a unitary modular fuel cell stack disposed in a compartment in the generator container. The use of a unitary modular fuel cell stack in a generator is similar in concept to that of a removable battery. The fuel cell stack is provided in a pre-assembled self-supporting configuration where the fuel cells are mounted to a common structural base having surrounding side walls defining a chamber. Associated generator equipment may also be mounted to the fuel cell stack configuration to be integral therewith, such as a fuel and oxidant supply and distribution systems, fuel reformation systems, fuel cell support systems, combustion, exhaust and spent fuel recirculation systems, and the like. The pre-assembled self-supporting fuel cell stack arrangement allows for easier assembly, installation, maintenance, better structural support and longer life of the fuel cells contained in the fuel cell stack.

  3. Solid oxide fuel cell generator with removable modular fuel cell stack configurations

    DOEpatents

    Gillett, J.E.; Dederer, J.T.; Zafred, P.R.; Collie, J.C.

    1998-04-21

    A high temperature solid oxide fuel cell generator produces electrical power from oxidation of hydrocarbon fuel gases such as natural gas, or conditioned fuel gases, such as carbon monoxide or hydrogen, with oxidant gases, such as air or oxygen. This electrochemical reaction occurs in a plurality of electrically connected solid oxide fuel cells bundled and arrayed in a unitary modular fuel cell stack disposed in a compartment in the generator container. The use of a unitary modular fuel cell stack in a generator is similar in concept to that of a removable battery. The fuel cell stack is provided in a pre-assembled self-supporting configuration where the fuel cells are mounted to a common structural base having surrounding side walls defining a chamber. Associated generator equipment may also be mounted to the fuel cell stack configuration to be integral therewith, such as a fuel and oxidant supply and distribution systems, fuel reformation systems, fuel cell support systems, combustion, exhaust and spent fuel recirculation systems, and the like. The pre-assembled self-supporting fuel cell stack arrangement allows for easier assembly, installation, maintenance, better structural support and longer life of the fuel cells contained in the fuel cell stack. 8 figs.

  4. Stacking interactions in PUF-RNA complexes

    SciTech Connect

    Yiling Koh, Yvonne; Wang, Yeming; Qiu, Chen; Opperman, Laura; Gross, Leah; Tanaka Hall, Traci M; Wickens, Marvin

    2012-07-02

    Stacking interactions between amino acids and bases are common in RNA-protein interactions. Many proteins that regulate mRNAs interact with single-stranded RNA elements in the 3' UTR (3'-untranslated region) of their targets. PUF proteins are exemplary. Here we focus on complexes formed between a Caenorhabditis elegans PUF protein, FBF, and its cognate RNAs. Stacking interactions are particularly prominent and involve every RNA base in the recognition element. To assess the contribution of stacking interactions to formation of the RNA-protein complex, we combine in vivo selection experiments with site-directed mutagenesis, biochemistry, and structural analysis. Our results reveal that the identities of stacking amino acids in FBF affect both the affinity and specificity of the RNA-protein interaction. Substitutions in amino acid side chains can restrict or broaden RNA specificity. We conclude that the identities of stacking residues are important in achieving the natural specificities of PUF proteins. Similarly, in PUF proteins engineered to bind new RNA sequences, the identity of stacking residues may contribute to 'target' versus 'off-target' interactions, and thus be an important consideration in the design of proteins with new specificities.

  5. Hydrocarbon-enhanced particulate filter regeneration via microwave ignition

    DOEpatents

    Gonze, Eugene V.; Brown, David B.

    2010-02-02

    A regeneration method for a particulate filter includes estimating a quantity of particulate matter trapped within the particulate filter, comparing the quantity of particulate matter to a predetermined quantity, heating at least a portion of the particulate filter to a combustion temperature of the particulate matter, and introducing hydrocarbon fuel to the particulate filter. The hydrocarbon fuel facilitates combustion of the particulate matter to regenerate the particulate filter.

  6. Development and Characterization of a High Performance Thin-Film Planar Solid-Oxide Fuel Cell Stack

    SciTech Connect

    Chung, B W; Chervin, C N; Haslam, J J; Pham, A; Glass, R S

    2004-04-07

    A planar solid oxide fuel cell (SOFC) was fabricated using a tape-cast Ni/yttria-stabilized zirconia (YSZ) anode support, a YSZ thin film electrolyte, and a composite cathode of YSZ and (La{sub 0.85}Sr{sup 0.14}){sub 0.98}MnO{sub 3} (LSM). Using pure hydrogen as the fuel gas, a three cell stack with a cross-flow design and external manifolds produced peak power densities of 0.85 W/cm{sup 2} and 0.41 W/cm{sup 2} at 800 C and 700 C, respectively. Using wet methane as the fuel gas, the stack produced a peak power density of 0.22 W/cm{sup 2} at 700 C. Individual cells in the stack showed identical current-voltage (I -V) characteristics. Stack lifetime was limited because of degradation of the cells from oxidation products coming from the metallic interconnect used.

  7. A polymer electrolyte fuel cell stack for stationary power generation from hydrogen fuel

    SciTech Connect

    Gottesfeld, S.

    1995-09-01

    The fuel cell is the most efficient device for the conversion of hydrogen fuel to electric power. As such, the fuel cell represents a key element in efforts to demonstrate and implement hydrogen fuel utilization for electric power generation. The low temperature, polymer electrolyte membrane fuel cell (PEMFC) has recently been identified as an attractive option for stationary power generation, based on the relatively simple and benign materials employed, the zero-emission character of the device, and the expected high power density, high reliability and low cost. However, a PEMFC stack fueled by hydrogen with the combined properties of low cost, high performance and high reliability has not yet been demonstrated. Demonstration of such a stack will remove a significant barrier to implementation of this advanced technology for electric power generation from hydrogen. Work done in the past at LANL on the development of components and materials, particularly on advanced membrane/electrode assemblies (MEAs), has contributed significantly to the capability to demonstrate in the foreseeable future a PEMFC stack with the combined characteristics described above. A joint effort between LANL and an industrial stack manufacturer will result in the demonstration of such a fuel cell stack for stationary power generation. The stack could operate on hydrogen fuel derived from either natural gas or from renewable sources. The technical plan includes collaboration with a stack manufacturer (CRADA). It stresses the special requirements from a PEMFC in stationary power generation, particularly maximization of the energy conversion efficiency, extension of useful life to the 10 hours time scale and tolerance to impurities from the reforming of natural gas.

  8. Field testing of particulate matter continuous emission monitors at the DOE Oak Ridge TSCA incinerator. Toxic Substances Control Act.

    PubMed

    Dunn, James E; Davis, Wayne T; Calcagno, James A; Allen, Marshall W

    2002-01-01

    A field study to evaluate the performance of three commercially available particulate matter (PM) continuous emission monitors (CEMs) was conducted in 1999-2000 at the US Department of Energy (DOE) Toxic Substances Control Act (TSCA) Incinerator. This study offers unique features that are believed to enhance the collective US experience with PM CEMs. The TSCA Incinerator is permitted to treat PCB-contaminated RCRA hazardous low-level radioactive wastes. The air pollution control system utilizes MACT control technology and is comprised of a rapid quench, venturi scrubber, packed bed scrubber, and two ionizing wet scrubbers in series, which create a saturated flue gas that must be conditioned by the CEMs prior to measurement. The incinerator routinely treats a wide variety of wastes including high and low BTU organic liquids, aqueous, and solid wastes. The various possible combinations for treating liquid and solid wastes may present a challenge in establishing a single, acceptable correlation relationship for individual CEMs. The effect of low-level radioactive material present in the waste is a unique site-specific factor not evaluated in previous tests. The three systems chosen for evaluation were two beta gauge devices and a light scattering device. The performance of the CEMs was evaluated using the requirements in draft Environmental Protection Agency (EPA) Performance Specification 11 (PS11) and Procedure 2. The results of Reference Method 5i stack tests for establishing statistical correlations between the reference method data and the CEMs responses are discussed.

  9. Water transport during startup and shutdown of polymer electrolyte fuel cell stacks.

    SciTech Connect

    Wang, X.; Tajiri, K.; Ahluwalia, R.; Nuclear Engineering Division

    2010-10-01

    A dynamic three-phase transport model is developed to analyze water uptake and transport in the membrane and catalyst layers of polymer electrolyte fuel cells during startup from subfreezing temperatures and subsequent shutdown. The initial membrane water content (?, the number of water molecules per sulfonic acid site) is found to be an important parameter that determines whether a successful unassisted self-start is possible. For a given initial subfreezing temperature at startup, there is a critical ? (?h), above which self-start is not possible because the product water completely engulfs the catalyst layers with ice before the stack can warm-up to 0 C. There is a second value of ? (?l), below which the stack can be self-started without forming ice. Between ?l and ?h, the stack can be self-started, but with intermediate formation of ice that melts as the stack warms up to 0 C. Both ?l and ?h are functions of the initial stack temperature, cell voltage at startup, membrane thickness, catalyst loading, and stack heat capacity. If the stack is purged during the previous shutdown by flowing air in the cathode passages, then depending on the initial amount of water in the membrane and gas diffusion layers and the initial stack temperature, it may not be possible to dry the membrane to the critical ? for a subsequent successful startup. There is an optimum ? for robust and rapid startup and shutdown. Startup and shutdown time and energy may be unacceptable if the ? is much less than the optimum. Conversely, a robust startup from subfreezing temperatures cannot be assured if the ? is much higher than this optimum.

  10. Stacking optimization of compressor blades of gas turbine engines

    NASA Technical Reports Server (NTRS)

    Cheu, Tsu-Chien

    1990-01-01

    A procedure is presented to obtain optimal designs of axial compressor blades with structural design constraints. Coefficients of the polynomials defining the circumferential tilting angles and the axial leaning distances of the airfoil cross sections from the initial design geometry are used as design variables. The compressor blades are modeled by 20-node solid elements. An efficient finite element method is developed for modal analysis and sensitivity analysis with respect to the design variables. Based on this information, a sequential linear programming method is applied to calculate the required change of geometry for the desired structural design constraints.

  11. High strength particulate ceramics

    DOEpatents

    Liles, Kenneth J.; Hoyer, Jesse L.; Mlynarski, Kenneth W.

    1991-01-01

    This invention relates to new and useful hard, dense, composite materials made from metallic nitrides such as titanium nitride when combined with aluminum oxide and aluminum nitride and a process comprising the steps of: (1) mixing constituent materials using kerosene as a mixing medium; (2) screening, settling, filtering, and washing the mixture in acetone; (3) filling and sealing said materials in a latex mold; (4) isostatically pressing the material into a compacted powder; and (5) sintering the compacted powder in a gas atmosphere at 1,850.degree. C. for two hours.

  12. Overlap zoned electrically heated particulate filter

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Chapman, Mark R [Brighton, MI

    2011-07-19

    A system includes a particulate matter (PM) filter that includes an upstream end for receiving exhaust gas and a downstream end. A zoned heater is arranged spaced from the upstream end and comprises N zones, where N is an integer greater than one, wherein each of the N zones comprises M sub-zones, where M is an integer greater than or equal to one, and wherein the N zones and the M sub-zones are arranged in P layers, where P is an integer greater than one. A control module selectively activates at least a selected one of the N zones to initiate regeneration in downstream portions of the PM filter from the one of the N zones and deactivates non-selected ones of the N zones.

  13. Electrically heated particulate matter filter soot control system

    DOEpatents

    Gonze, Eugene V.; Paratore, Jr., Michael J.; Bhatia, Garima

    2016-03-15

    A regeneration system includes a particulate matter (PM) filter with an upstream end for receiving exhaust gas and a downstream end. A control module determines a current soot loading level of the PM filter and compares the current soot loading level to a predetermined soot loading level. The control module permits regeneration of the PM filter when the current soot loading level is less than the predetermined soot loading level.

  14. An Investigation of Particulate Behavior in Solid Rocket Motors

    DTIC Science & Technology

    1981-06-01

    High-Speed Cinematography Metallized Propellants Holography Light Scattering 20. AT~tFT (C.U50us on Fever aide if ft oGo. IF d Ids t I- I IO 1101...Page I. INTRODUCTION ---------------------------------- 10 II. -METHOD OF INVESTIGATION ----------------------- 19 III. HIGH-SPEED CINEMATOGRAPHY ...particulate characteristics within the gas phase. To that purpose four experimental techniques were chosen: a. High speed cinematography for the observation

  15. Cross-flow, filter-sorbent catalyst for particulate, SO sub 2 and NO sub x control

    SciTech Connect

    Benedek, K. , Inc., Cambridge, MA ); Flytzani-Stephanopoulos, M. )

    1991-08-01

    This report describes a new concept for integrated pollutant control: a cross-flow filter comprised of layered, gas permeable membranes that act a particulate filter, an SO{sub 2} sorbent, and a NO{sub x} reduction catalyst.

  16. Particulate emissions from diesel engines: correlation between engine technology and emissions

    PubMed Central

    2014-01-01

    In the last 30 years, diesel engines have made rapid progress to increased efficiency, environmental protection and comfort for both light- and heavy-duty applications. The technical developments include all issues from fuel to combustion process to exhaust gas aftertreatment. This paper provides a comprehensive summary of the available literature regarding technical developments and their impact on the reduction of pollutant emission. This includes emission legislation, fuel quality, diesel engine- and exhaust gas aftertreatment technologies, as well as particulate composition, with a focus on the mass-related particulate emission of on-road vehicle applications. Diesel engine technologies representative of real-world on-road applications will be highlighted. Internal engine modifications now make it possible to minimize particulate and nitrogen oxide emissions with nearly no reduction in power. Among these modifications are cooled exhaust gas recirculation, optimized injections systems, adapted charging systems and optimized combustion processes with high turbulence. With introduction and optimization of exhaust gas aftertreatment systems, such as the diesel oxidation catalyst and the diesel particulate trap, as well as NOx-reduction systems, pollutant emissions have been significantly decreased. Today, sulfur poisoning of diesel oxidation catalysts is no longer considered a problem due to the low-sulfur fuel used in Europe. In the future, there will be an increased use of bio-fuels, which generally have a positive impact on the particulate emissions and do not increase the particle number emissions. Since the introduction of the EU emissions legislation, all emission limits have been reduced by over 90%. Further steps can be expected in the future. Retrospectively, the particulate emissions of modern diesel engines with respect to quality and quantity cannot be compared with those of older engines. Internal engine modifications lead to a clear reduction of the

  17. Particulate emissions from diesel engines: correlation between engine technology and emissions.

    PubMed

    Fiebig, Michael; Wiartalla, Andreas; Holderbaum, Bastian; Kiesow, Sebastian

    2014-03-07

    In the last 30 years, diesel engines have made rapid progress to increased efficiency, environmental protection and comfort for both light- and heavy-duty applications. The technical developments include all issues from fuel to combustion process to exhaust gas aftertreatment. This paper provides a comprehensive summary of the available literature regarding technical developments and their impact on the reduction of pollutant emission. This includes emission legislation, fuel quality, diesel engine- and exhaust gas aftertreatment technologies, as well as particulate composition, with a focus on the mass-related particulate emission of on-road vehicle applications. Diesel engine technologies representative of real-world on-road applications will be highlighted.Internal engine modifications now make it possible to minimize particulate and nitrogen oxide emissions with nearly no reduction in power. Among these modifications are cooled exhaust gas recirculation, optimized injections systems, adapted charging systems and optimized combustion processes with high turbulence. With introduction and optimization of exhaust gas aftertreatment systems, such as the diesel oxidation catalyst and the diesel particulate trap, as well as NOx-reduction systems, pollutant emissions have been significantly decreased. Today, sulfur poisoning of diesel oxidation catalysts is no longer considered a problem due to the low-sulfur fuel used in Europe. In the future, there will be an increased use of bio-fuels, which generally have a positive impact on the particulate emissions and do not increase the particle number emissions.Since the introduction of the EU emissions legislation, all emission limits have been reduced by over 90%. Further steps can be expected in the future. Retrospectively, the particulate emissions of modern diesel engines with respect to quality and quantity cannot be compared with those of older engines. Internal engine modifications lead to a clear reduction of the

  18. Gas sampling system for reactive gas-solid mixtures

    DOEpatents

    Daum, Edward D.; Downs, William; Jankura, Bryan J.; McCoury, Jr., John M.

    1990-01-01

    An apparatus and method for sampling gas containing a reactive particulate solid phase flowing through a duct and for communicating a representative sample to a gas analyzer. A sample probe sheath 32 with an angular opening 34 extends vertically into a sample gas duct 30. The angular opening 34 is opposite the gas flow. A gas sampling probe 36 concentrically located within sheath 32 along with calibration probe 40 partly extends in the sheath 32. Calibration probe 40 extends further in the sheath 32 than gas sampling probe 36 for purging the probe sheath area with a calibration gas during calibration.

  19. Gas sampling system for reactive gas-solid mixtures

    DOEpatents

    Daum, Edward D.; Downs, William; Jankura, Bryan J.; McCoury, Jr., John M.

    1989-01-01

    An apparatus and method for sampling a gas containing a reactive particulate solid phase flowing through a duct and for communicating a representative sample to a gas analyzer. A sample probe sheath 32 with an angular opening 34 extends vertically into a sample gas duct 30. The angular opening 34 is opposite the gas flow. A gas sampling probe 36 concentrically located within sheath 32 along with calibration probe 40 partly extend in the sheath 32. Calibration probe 40 extends further in the sheath 32 than gas sampling probe 36 for purging the probe sheath area with a calibration gas during calibration.

  20. The movement of small particulate matter in the early solar system and the formation of satellites

    NASA Technical Reports Server (NTRS)

    Gold, T.

    1974-01-01

    The motions of the abundant small particulate matter in the early solar system are discussed. The effects of gas drag and resonance effects of perturbing forces could have led to accretion and differentiation of the matter. The composition of the moon and the existence of the rings of Saturn can be explained on the basis of the assembly of small particulate matter in satellite orbits around the planets.

  1. Manifold gasket accommodating differential movement of fuel cell stack

    DOEpatents

    Kelley, Dana A.; Farooque, Mohammad

    2007-11-13

    A gasket for use in a fuel cell system having at least one externally manifolded fuel cell stack, for sealing the manifold edge and the stack face. In accordance with the present invention, the gasket accommodates differential movement between the stack and manifold by promoting slippage at interfaces between the gasket and the dielectric and between the gasket and the stack face.

  2. UV PRE-IONIZED RAIL-GAP SWITCH FOR STACKED BLUMLEIN PULSE GENERATORS*

    SciTech Connect

    Rhodes, M A

    2005-05-09

    Stacked Blumlein Pulse Generators comprised of parallel-plate transmission lines are potentially a useful pulse-power architecture for high-gradient, compact, electron-beam accelerators and other applications. Such pulse generators require a low-inductance, fast (<5ns) switch per stage to erect the stack and produce the desired output pulse. We are developing a rail-gap switch tightly integrated with the stack for this application. We employ ultraviolet light (UV) to pre-ionize the switch, which facilitates prompt, low-jitter, and potentially multichannel operation. A novel aspect of our switch is that the source of the UV is a conventional Xenon flashlamp. This allows variation of the switch pressure and gas without affecting the flashlamp operation. We can operate our switch in either triggered or self-breaking mode. Here we present initial results of a two-stage, stacked Blumlein operating in self-break mode. We compare the switch performance to gas-switch scaling laws with respect to resistive-phase risetime and trigger delay as a function of gas density, gap-length, and gap-voltage.

  3. Enhanced dynamical stability with harmonic slip stacking

    NASA Astrophysics Data System (ADS)

    Eldred, Jeffrey; Zwaska, Robert

    2016-10-01

    We develop a configuration of radio-frequency (rf) cavities to dramatically improve the performance of slip stacking. Slip stacking is an accumulation technique used at Fermilab to nearly double proton intensity by maintaining two beams of different momenta in the same storage ring. The two particle beams are longitudinally focused in the Recycler by two 53 MHz 100 kV rf cavities with a small frequency difference between them. We propose an additional 106 MHz 20 kV rf cavity with a frequency at the double the average of the upper and lower main rf frequencies. We show the harmonic rf cavity cancels out the resonances generated between the two main rf cavities and we derive the relationship between the harmonic rf voltage and the main rf voltage. We find the area factors that can be used to calculate the available phase space area for any set of beam parameters without individual simulation. We establish Booster beam quality requirements to achieve 99% slip stacking efficiency. We measure the longitudinal distribution of the Booster beam and use it to generate a realistic beam model for slip stacking simulation. We demonstrate that the harmonic rf cavity can not only reduce particle loss during slip stacking, but also reduce the final longitudinal emittance.

  4. Technical description of Stack 296-B-5

    SciTech Connect

    Ridge, T.M.

    1994-11-15

    Of particular concern to facilities on the Hanford site is Title 40, Code of Federal Regulations, Chapter 40, Part 61, Subpart H, ``National emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities.`` Assessments of facility stacks and potential radionuclide emissions determined whether these stacks would be subject to the sampling and monitoring requirements of 40 CFR 61, Subpart H. Stack 296-B-5 exhausts 221-BB building which houses tanks containing B Plant steam condensate and B Plant process condensate from the operation of the low-level waste concentrator. The assessment of potential radionuclide emissions from the 296-B-5 stack resulted in an effective dose equivalent to the maximally exposed individual of less than 0.1 millirem per year. Therefore, the stack is not subject to the sampling and monitoring requirements of 40 CFR 61, Subpart H. However, the sampling and monitoring system must be in compliance with the Environmental Compliance Manual, WHC-CM-7-5. Currently, 296-B-5 is sampled continuously with a record sampler and continuous air monitor (CAM).

  5. Fungal melanins differ in planar stacking distances.

    PubMed

    Casadevall, Arturo; Nakouzi, Antonio; Crippa, Pier R; Eisner, Melvin

    2012-01-01

    Melanins are notoriously difficult to study because they are amorphous, insoluble and often associated with other biological materials. Consequently, there is a dearth of structural techniques to study this enigmatic pigment. Current models of melanin structure envision the stacking of planar structures. X ray diffraction has historically been used to deduce stacking parameters. In this study we used X ray diffraction to analyze melanins derived from Cryptococcus neoformans, Aspergillus niger, Wangiella dermatitides and Coprinus comatus. Analysis of melanin in melanized C. neoformans encapsulated cells was precluded by the fortuitous finding that the capsular polysaccharide had a diffraction spectrum that was similar to that of isolated melanin. The capsular polysaccharide spectrum was dominated by a broad non-Bragg feature consistent with origin from a repeating structural motif that may arise from inter-molecular interactions and/or possibly gel organization. Hence, we isolated melanin from each fungal species and compared diffraction parameters. The results show that the inferred stacking distances of fungal melanins differ from that reported for synthetic melanin and neuromelanin, occupying intermediate position between these other melanins. These results suggest that all melanins have a fundamental diffracting unit composed of planar graphitic assemblies that can differ in stacking distance. The stacking peak appears to be a distinguishing universal feature of melanins that may be of use in characterizing these enigmatic pigments.

  6. Contemporary sample stacking in analytical electrophoresis.

    PubMed

    Malá, Zdena; Šlampová, Andrea; Křivánková, Ludmila; Gebauer, Petr; Boček, Petr

    2015-01-01

    This contribution is a methodological review of the publications about the topic from the last 2 years. Therefore, it is primarily organized according to the methods and procedures used in surveyed papers and the origin and type of sample and specification of analytes form the secondary structure. The introductory part about navigation in the architecture of stacking brings a brief characterization of the various stacking methods, with the description of mutual links to each other and important differences among them. The main body of the article brings a survey of publications organized according to main principles of stacking and then according to the origin and type of the sample. Provided that the paper cited gave explicitly the relevant data, information about the BGE(s) used, procedure, detector employed, and reached LOD and/or concentration effect is given. The papers where the procedure used is a combination of diverse fragments and parts of various stacking techniques are mentioned in a special section on combined techniques. The concluding remarks in the final part of the review evaluate present state of art and the trends of sample stacking in CE.

  7. Year-round records of gas and particulate carboxylic acids (formate and acetate) in the boundary layer at Dumont d'Urville (coastal Antarctica): Production of carboxylic acids from biogenic NMHC emissions from the Antarctic ocean

    NASA Astrophysics Data System (ADS)

    Legrand, M.; Preunkert, S.; Jourdain, B.

    2003-04-01

    Multiple year-round concentrations of acetic and formic acids were measured both in gas and aerosol phases at Dumont d'Urville (DDU, a coastal Antarctic site: 66^o40'S, 140^o01'E) by using mist chamber and aerosol filter sampling. Aerosol levels of the 2 carboxylates range from less than one ng m-3 in winter to 5--10 ng m-3 in summer. Comparison with gas phase concentrations shows that almost 99% of the 2 carboxylic acids are present in the gas phase. Concentrations of formic acid in the gas phase are minima in June--July (70 ng m-3) and increase regularly towards summer months when levels reach ˜400 ng m-3. Concentrations of acetic acid in the gas phase exhibit a more well-marked seasonal cycle with values remaining close to 50 ng m-3 from April to October and strongly increase during summer months (mean value of 800 ng m-3). Such a strong seasonal cycle of carboxylic acids in the high southern latitude marine boundary layer displays with observations made at numerous continental sites where a more weak seasonality is generally observed. It is suggested that carboxylic acids present at DDU mainly originate from biogenic emissions from the Antarctic ocean which are expected to closely follow annual cycle of the sea ice extent and solar radiation, affecting in particular photochemical production of alkenes from dissolved organic carbon released from phytoplancton. Summer levels of carboxylic acids are discussed in terms of air-sea fluxes of NMHCs and photochemical production of carboxylic acids from ozone-alkene reactions and HO_2 reaction with peroxyacetal radical in these poor NOx environments.

  8. Inflatable containment diaphragm for sealing and removing stacks

    DOEpatents

    Meskanick, G.R.; Rosso, D.T.

    1993-04-13

    A diaphragm with an inflatable torus-shaped perimeter is used to seal at least one end of a stack so that debris that might be hazardous will not be released during removal of the stack. A diaphragm is inserted and inflated in the lower portion of a stack just above where the stack is to be cut such that the perimeter of the diaphragm expands and forms a seal against the interior surface of the stack.

  9. PARTICULATE EMISSION MEASUREMENTS FROM CONTROLLED CONSTRUCTION ACTIVITIES

    EPA Science Inventory

    The report summarized the results of field testing of the effectiveness of control measures for sources of fugitive particulate emissions found at construction sites. The effectiveness of watering temporary, unpaved travel surfaces on emissions of particulate matter with aerodyna...

  10. Fuel gas desulfurization

    DOEpatents

    Yang, Ralph T.; Shen, Ming-Shing

    1981-01-01

    A method for removing sulfurous gases such as H.sub.2 S and COS from a fuel gas is disclosed wherein limestone particulates containing iron sulfide provide catalytic absorption of the H.sub.2 S and COS by the limestone. The method is effective at temperatures of 400.degree. C. to 700.degree. C. in particular.

  11. Low exhaust temperature electrically heated particulate matter filter system

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Paratore, Jr., Michael J.; Bhatia, Garima [Bangalore, IN

    2012-02-14

    A system includes a particulate matter (PM) filter, a sensor, a heating element, and a control module. The PM filter includes with an upstream end that receives exhaust gas, a downstream end and multiple zones. The sensor detects a temperature of the exhaust gas. The control module controls current to the heating element to convection heat one of the zones and initiate a regeneration process. The control module selectively increases current to the heating element relative to a reference regeneration current level when the temperature is less than a predetermined temperature.

  12. A novel optical scattering collection system for particulate monitoring applications

    SciTech Connect

    Bernacki, B.E.; Miller, A.C. Jr.; Nuspliger, R.J.

    1996-05-01

    Light collecting systems often require radically different optical surfaces than those commonly found in optical imaging systems. An optical particulate monitor must probe a volume in emission stacks to obtain a good statistical distribution of suspended particles. However, ideal imaging systems map object planes into conjugate image planes and can probe only small volumes. The authors describe the design, fabrication and performance of a novel optical scattering collection system that exploits precision-engineered reflective conical surfaces (axicons) in a telescopic arrangement that maps a line in object space onto the detector plane in image space. Such non-spherical surfaces are nearly impossible to fabricate using traditional methods, but can readily be made using the deterministic method of single-point diamond turning. In addition to complex optical surfaces, single-point diamond turning also makes possible the precision engineering of reference surfaces useful for built-in alignment of multiple surfaces and rapid assembly of the finished system.

  13. Method and apparatus for the separation of a gas-solids mixture in a circulating fluidized bed reactor

    DOEpatents

    Vimalchand, Pannalal; Liu, Guohai; Peng, WanWang

    2010-08-10

    The system of the present invention includes a centripetal cyclone for separating particulate material from a particulate laden gas solids stream. The cyclone includes a housing defining a conduit extending between an upstream inlet and a downstream outlet. In operation, when a particulate laden gas-solids stream passes through the upstream housing inlet, the particulate laden gas-solids stream is directed through the conduit and at least a portion of the solids in the particulate laden gas-solids stream are subjected to a centripetal force within the conduit.

  14. TESTING FOR CPT VIOLATION IN Bstack">0stack">s SEMILEPTONIC DECAYS

    NASA Astrophysics Data System (ADS)

    Kooten, R. Van

    2014-01-01

    A DØ analysis measuring the charge asymmetry Astack">bstack">sl of like-sign dimuon events due to semileptonic b-hadron decays at the Fermilab Tevatron Collider has shown indications of possible anomalous CP violation in the mixing of neutral B mesons. This result has been used to extract the first senstivity to CPT violation in the Bstack">0stack">s system. An analysis to explore further this anomaly by specifically measuring the semileptonic charge asymmetry, astack">sstack">sl, in Bstack">0stack">s decays is described, as well as how a variant of this analysis can be used to explore a larger set of CPT-violating parameters in the Bstack">0stack">s system for the first time.

  15. Particulate matter and preterm birth

    EPA Science Inventory

    Particulate matter (PM) has been variably associated with preterm birth (PTB) (gestation <37 weeks), but the role played by specific chemical components of PM has been little studied. We examined the association between ambient PM <2.5 micrometers in aerodynamic diameter (PM2.S) ...

  16. Source Testing for Particulate Matter.

    ERIC Educational Resources Information Center

    DeVorkin, Howard

    Developed for presentation at the 12th Conference on Methods in Air Pollution and Industrial Hygiene Studies, University of Southern California, April, 1971, this outline covers procedures for the testing of particulate matter. These are: (1) basic requirements, (2) information required, (3) collection of samples, (4) processing of samples, (5)…

  17. MODELING PARTICULATE CHARGING IN ESPS

    EPA Science Inventory

    In electrostatic precipitators there is a strong interaction between the particulate space charge and the operating voltage and current of an electrical section. Calculating either the space charge or the operating point when the other is fixed is not difficult, but calculating b...

  18. Electrochemical Detection in Stacked Paper Networks.

    PubMed

    Liu, Xiyuan; Lillehoj, Peter B

    2015-08-01

    Paper-based electrochemical biosensors are a promising technology that enables rapid, quantitative measurements on an inexpensive platform. However, the control of liquids in paper networks is generally limited to a single sample delivery step. Here, we propose a simple method to automate the loading and delivery of liquid samples to sensing electrodes on paper networks by stacking multiple layers of paper. Using these stacked paper devices (SPDs), we demonstrate a unique strategy to fully immerse planar electrodes by aqueous liquids via capillary flow. Amperometric measurements of xanthine oxidase revealed that electrochemical sensors on four-layer SPDs generated detection signals up to 75% higher compared with those on single-layer paper devices. Furthermore, measurements could be performed with minimal user involvement and completed within 30 min. Due to its simplicity, enhanced automation, and capability for quantitative measurements, stacked paper electrochemical biosensors can be useful tools for point-of-care testing in resource-limited settings.

  19. Progress of MCFC stack technology at Toshiba

    SciTech Connect

    Hori, M.; Hayashi, T.; Shimizu, Y.

    1996-12-31

    Toshiba is working on the development of MCFC stack technology; improvement of cell characteristics, and establishment of separator technology. For the cell technology, Toshiba has concentrated on both the restraints of NiO cathode dissolution and electrolyte loss from cells, which are the critical issues to extend cell life in MCFC, and great progress has been made. On the other hand, recognizing that the separator is one of key elements in accomplishing reliable and cost-competitive MCFC stacks, Toshiba has been accelerating the technology establishment and verification of an advanced type separator. A sub-scale stack with such a separator was provided for an electric generating test, and has been operated for more than 10,000 hours. This paper presents several topics obtained through the technical activities in the MCFC field at Toshiba.

  20. Fuel cell stack monitoring and system control

    DOEpatents

    Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

    2005-01-25

    A control method for monitoring a fuel cell stack in a fuel cell system in which the actual voltage and actual current from the fuel cell stack are monitored. A preestablished relationship between voltage and current over the operating range of the fuel cell is established. A variance value between the actual measured voltage and the expected voltage magnitude for a given actual measured current is calculated and compared with a predetermined allowable variance. An output is generated if the calculated variance value exceeds the predetermined variance. The predetermined voltage-current for the fuel cell is symbolized as a polarization curve at given operating conditions of the fuel cell. Other polarization curves may be generated and used for fuel cell stack monitoring based on different operating pressures, temperatures, hydrogen quantities.

  1. High frequency model of stacked film capacitors

    NASA Astrophysics Data System (ADS)

    Talbert, T.; Joubert, C.; Daude, N.; Glaize, C.

    2001-11-01

    Polypropylene metallized capacitors are of general use in power electronics because of their reliability, their self-healing capabilities, and their low price. Though the behavior of metallized coiled capacitors has been discussed, no work has been carried out on stacked and flattened metallized capacitors. The purpose of this article is to suggest an analytical model of resonance frequency, stray inductance and impedance of stacked capacitors. We first solve the equation of propagation of the magnetic potential vector (A) in the dielectric of an homogeneous material. Then, we suggest an original method of resolution, like the one used for resonant cavities, in order to present an analytical solution of the problem. Finally, we give some experimental results proving that the physical knowledge of the parameters of the capacitor (dimension of the component, and material constants), enables us to calculate an analytical model of resonance frequency, stray inductance and impedance of stacked capacitors.

  2. Particulate emissions from concentrated animal feeding operations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Concentrated animal feeding operations (CAFOs), including open beef cattle feedlots, swine facilities, and poultry facilities, can emit large amounts of particulate matter, including TSP (total suspended particulates), PM10 (particulate matter with equivalent aerodynamic diameter of 10 mm or less) a...

  3. The Morgantown Energy Technology Center`s particulate cleanup program

    SciTech Connect

    Dennis, R.A.

    1995-12-01

    The development of integrated gasification combined cycle (IGCC) and pressurized fluidized-bed combustion (PFBC) power systems has made it possible to use coal while still protecting the environment. Such power systems significantly reduce the pollutants associated with coal-fired plants built before the 1970s. This superior environmental performance and related high system efficiency is possible, in part, because particulate gas-stream cleanup is conducted at high-temperature and high-pressure process conditions. A main objective of the Particulate Cleanup Program at the Morgantown Energy Technology Center (METC) is to ensure the success of the CCT demonstration projects. METC`s Particulate Cleanup Program supports research, development, and demonstration in three areas: (1) filter-system development, (2) barrier-filter component development, and (3) ash and char characterization. The support is through contracted research, cooperative agreements, Cooperative Research And Development Agreements (CRADAs), and METC`s own in-house research. This paper describes METC`s Particulate Cleanup Program.

  4. Electrification of particulate entrained fluid flows-Mechanisms, applications, and numerical methodology

    NASA Astrophysics Data System (ADS)

    Wei, Wei; Gu, Zhaolin

    2015-10-01

    Particulates in natural and industrial flows have two basic forms: liquid (droplet) and solid (particle). Droplets would be charged in the presence of the applied electric field (e.g. electrospray). Similar to the droplet charging, particles can also be charged under the external electric field (e.g. electrostatic precipitator), while in the absence of external electric field, tribo-electrostatic charging is almost unavoidable in gas-solid two-phase flows due to the consecutive particle contacts (e.g. electrostatic in fluidized bed or wind-blown sand). The particle charging may be beneficial, or detrimental. Although electrostatics in particulate entrained fluid flow systems have been so widely used and concerned, the mechanisms of particulate charging are still lack of a thorough understanding. The motivation of this review is to explore a clear understanding of particulate charging and movement of charged particulate in two-phase flows, by summarizing the electrification mechanisms, physical models of particulate charging, and methods of charging/charged particulate entrained fluid flow simulations. Two effective methods can make droplets charged in industrial applications: corona charging and induction charging. The droplet charge to mass ratio by corona charging is more than induction discharge. The particle charging through collisions could be attributed to electron transfer, ion transfer, material transfer, and/or aqueous ion shift on particle surfaces. The charges on charged particulate surface can be measured, nevertheless, the charging process in nature or industry is difficult to monitor. The simulation method might build a bridge of investigating from the charging process to finally charged state on particulate surface in particulate entrained fluid flows. The methodology combining the interface tracking under the action of the applied electric with the fluid flow governing equations is applicable to the study of electrohydrodynamics problems. The charge

  5. Three wafer stacking for 3D integration.

    SciTech Connect

    Greth, K. Douglas; Ford, Christine L.; Lantz, Jeffrey W.; Shinde, Subhash L.; Timon, Robert P.; Bauer, Todd M.; Hetherington, Dale Laird; Sanchez, Carlos Anthony

    2011-11-01

    Vertical wafer stacking will enable a wide variety of new system architectures by enabling the integration of dissimilar technologies in one small form factor package. With this LDRD, we explored the combination of processes and integration techniques required to achieve stacking of three or more layers. The specific topics that we investigated include design and layout of a reticle set for use as a process development vehicle, through silicon via formation, bonding media, wafer thinning, dielectric deposition for via isolation on the wafer backside, and pad formation.

  6. Fuel cell stack monitoring and system control

    DOEpatents

    Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

    2004-02-17

    A control method for monitoring a fuel cell stack in a fuel cell system in which the actual voltage and actual current from the fuel cell stack are monitored. A preestablished relationship between voltage and current over the operating range of the fuel cell is established. A variance value between the actual measured voltage and the expected voltage magnitude for a given actual measured current is calculated and compared with a predetermined allowable variance. An output is generated if the calculated variance value exceeds the predetermined variance. The predetermined voltage-current for the fuel cell is symbolized as a polarization curve at given operating conditions of the fuel cell.

  7. Effects of Endwall Geometry and Stacking on Two-Stage Supersonic Turbine Performance

    NASA Technical Reports Server (NTRS)

    Dorney, Daniel J.; Griffin, Lisa W.; Huber, Frank W.; Sondak, Douglas L.; Turner, Jim (Technical Monitor)

    2002-01-01

    The drive towards high-work turbines has led to designs which can be compact, transonic, supersonic, counter rotating, or use a dense drive gas. These aggressive designs can lead to strong secondary flows and airfoil flow separation. In many cases the secondary and separated flows can be minimized by contouring the hub/shroud endwalls and/or modifying the airfoil stacking. In this study, three-dimensional unsteady Navier-Stokes simulations were performed to study three different endwall shapes between the first-stage vanes and rotors, as well as two different stackings for the first-stage vanes. The predicted results indicate that changing the stacking of the first-stage vanes can significantly impact endwall separation (and turbine performance) in regions where the endwall profile changes.

  8. Comparative studies on performance of single cell and PEMFC stack

    NASA Astrophysics Data System (ADS)

    Onggo, Holia; Irmawati, Yuyun; Yudianti, Rike

    2016-02-01

    Single-cell, 2-cell and 3-cell of polymer electrolyte membrane fuel cells (PEMFCs) with an active area of 9 cm2 per cell have been fabricated and characterized its performance and electrochemical properties. The membrane electrode assembly (MEA) was prepared by hot pressing commercial gas diffusion electrodes (Pt loading 0.5 mg/cm2) on pre-treated Nafion 117 membrane. The experimental results are presented as polarization and power output curves which show the effects of varying H2/O2 back pressures on the PEMFC performance. Three varying H2/O2 volumetric flow-rates for three different cell stacks were employed based on the optimal condition to produce good performance of stack. Cell performances for single cell, 2-cell, or 3-cell PEMFCs are slightly comparable with the power output 1.2 - 1.3 W in average. Enhancing back pressure induces increasing performance PEMFCs as indicated by changing the power from 1.19 W (open end) to 1.33W (15 psi).

  9. A thermal stack structure for measurement of fluid flow

    NASA Astrophysics Data System (ADS)

    Zhao, Hao; Mitchell, S. J. N.; Campbell, D. H.; Gamble, Harold S.

    2003-03-01

    A stacked thermal structure for fluid flow sensing has been designed, fabricated, and tested. A double-layer polysilicon process was employed in the fabrication. Flow measurement is based on the transfer of heat from a temperature sensor element to the moving fluid. The undoped or lightly doped polysilicon temperature sensor is located on top of a heavily doped polysilicon heater element. A dielectric layer between the heater and the sensor elements provides both thermal coupling and electrical isolation. In comparison to a hot-wire flow sensor, the heating and sensing functions are separated, allowing the electrical characteristics of each to be optimized. Undoped polysilicon has a large temperature coefficient of resistance (TCR) up to 7 %/K and is thus a preferred material for the sensor. However, heavily doped polysilicon is preferred for the heater due to its lower resistance. The stacked flow sensor structure offers a high thermal sensitivity making it especially suitable for medical applications where the working temperatures are restricted. Flow rates of various fluids can be measured over a wide range. The fabricated flow sensors were used to measure the flow rate of water in the range μl - ml/min and gas (Helium) in the range 10 - 100ml/min.

  10. Velocity model optimization for surface microseismic monitoring via amplitude stacking

    NASA Astrophysics Data System (ADS)

    Jiang, Haiyu; Wang, Zhongren; Zeng, Xiaoxian; Lü, Hao; Zhou, Xiaohua; Chen, Zubin

    2016-12-01

    A usable velocity model in microseismic projects plays a crucial role in achieving statistically reliable microseismic event locations. Existing methods for velocity model optimization rely mainly on picking arrival times at individual receivers. However, for microseismic monitoring with surface stations, seismograms of perforation shots have such low signal-to-noise ratios (S/N) that they do not yield sufficiently reliable picks. In this study, we develop a framework for constructing a 1-D flat-layered a priori velocity model using a non-linear optimization technique based on amplitude stacking. The energy focusing of the perforation shot is improved thanks to very fast simulated annealing (VFSA), and the accuracies of shot relocations are used to evaluate whether the resultant velocity model can be used for microseismic event location. Our method also includes a conventional migration-based location technique that utilizes successive grid subdivisions to improve computational efficiency and source location accuracy. Because unreasonable a priori velocity model information and interference due to additive noise are the major contributors to inaccuracies in perforation shot locations, we use velocity model optimization as a compensation scheme. Using synthetic tests, we show that accurate locations of perforation shots can be recovered to within 2 m, even with pre-stack S/N ratios as low as 0.1 at individual receivers. By applying the technique to a coal-bed gas reservoir in Western China, we demonstrate that perforation shot location can be recovered to within the tolerance of the well tip location.

  11. Pressurized Testing of Solid Oxide Electrolysis Stacks with Advanced Electrode-Supported Cells

    SciTech Connect

    J. E. O'Brien; X. Zhang; G. K. Housley; K. DeWall; L. Moore-McAteer; G. Tao

    2012-06-01

    A new facility has been developed at the Idaho National Laboratory for pressurized testing of solid oxide electrolysis stacks. Pressurized operation is envisioned for large-scale hydrogen production plants, yielding higher overall efficiencies when the hydrogen product is to be delivered at elevated pressure for tank storage or pipelines. Pressurized operation also supports higher mass flow rates of the process gases with smaller components. The test stand can accommodate cell dimensions up to 8.5 cm x 8.5 cm and stacks of up to 25 cells. The pressure boundary for these tests is a water-cooled spool-piece pressure vessel designed for operation up to 5 MPa. The stack is internally manifolded and operates in cross-flow with an inverted-U flow pattern. Feed-throughs for gas inlets/outlets, power, and instrumentation are all located in the bottom flange. The entire spool piece, with the exception of the bottom flange, can be lifted to allow access to the internal furnace and test fixture. Lifting is accomplished with a motorized threaded drive mechanism attached to a rigid structural frame. Stack mechanical compression is accomplished using springs that are located inside of the pressure boundary, but outside of the hot zone. Initial stack heatup and performance characterization occurs at ambient pressure followed by lowering and sealing of the pressure vessel and subsequent pressurization. Pressure equalization between the anode and cathode sides of the cells and the stack surroundings is ensured by combining all of the process gases downstream of the stack. Steady pressure is maintained by means of a backpressure regulator and a digital pressure controller. A full description of the pressurized test apparatus is provided in this paper.

  12. Stack and fugitive emissions of major air pollutants from typical brick kilns in China.

    PubMed

    Chen, Yuanchen; Du, Wei; Zhuo, Shaojie; Liu, Weijian; Liu, Yuanlong; Shen, Guofeng; Wu, Shuiping; Li, Jianjun; Zhou, Bianhong; Wang, Gehui; Zeng, Eddy Y; Cheng, Hefa; Liu, Wenxin; Tao, Shu

    2017-02-22

    Little information exists on emission factors (EFs, quantities of pollutants emitted per unit of fuel consumed) for brick kilns in China, although brick kilns are important emission sources of many air pollutants, and 45% of the world's bricks are produced in China. In this study, EFs of carbon dioxide (CO2), carbon monoxide (CO), sulfur dioxide (SO2), nitrogen oxides (NOx), particulate matters (PMs), black carbon (BC), organic carbon (OC), and polycyclic aromatic hydrocarbons (PAHs) for brick kilns were derived based on field measurements of a total of 18 brick kilns of major types in China. This was the first study to quantify EFs of both stack and fugitive sources based on a modified carbon balance method that was developed for this study. The EFs of most pollutants, especially the incomplete combustion products in fugitive emissions, were much higher than those for stack emissions, indicating a substantial underestimation of total emissions when leakage is not taken into consideration. This novel method can be applied to quantify emissions from other similar sources with both stack and fugitive emissions.

  13. Asymmetrical reverse vortex flow due to induced-charge electro-osmosis around carbon stacking structures

    NASA Astrophysics Data System (ADS)

    Sugioka, Hideyuki

    2011-05-01

    Broken symmetry of vortices due to induced-charge electro-osmosis (ICEO) around stacking structures is important for the generation of a large net flow in a microchannel. Following theoretical predictions in our previous study, we herein report experimental observations of asymmetrical reverse vortex flows around stacking structures of carbon posts with a large height (~110 μm) in water, prepared by the pyrolysis of a photoresist film in a reducing gas. Further, by the use of a coupled calculation method that considers boundary effects precisely, the experimental results, except for the problem of anomalous flow reversal, are successfully explained. That is, unlike previous predictions, the precise calculations here show that stacking structures accelerate a reverse flow rather than suppressing it for a microfluidic channel because of the deformation of electric fields near the stacking portions; these structures can also generate a large net flow theoretically in the direction opposite that of a previous prediction for a standard vortex flow. Furthermore, by solving the one-dimensional Poisson-Nernst-Plank (PNP) equations in the presence of ac electric fields, we find that the anomalous flow reversal occurs by the phase retardation between the induced diffuse charge and the tangential electric field. In addition, we successfully explain the nonlinearity of the flow velocity on the applied voltage by the PNP analysis. In the future, we expect to improve the pumping performance significantly by using stacking structures of conductive posts along with a low-cost process.

  14. Zero-line modes at stacking faulted domain walls in multilayer graphene

    NASA Astrophysics Data System (ADS)

    Lee, Changhee; Kim, Gunn; Jung, Jeil; Min, Hongki

    2016-09-01

    Rhombohedral multilayer graphene is a physical realization of the chiral two-dimensional electron gas that can host zero-line modes (ZLMs), also known as kink states, when the local gap opened by inversion symmetry breaking potential changes sign in real space. Here we study how the variations in the local stacking coordination of multilayer graphene affects the formation of the ZLMs. Our analysis indicates that the valley Hall effect develops whenever an interlayer potential difference is able to open up a band gap in stacking faulted multilayer graphene, and that ZLMs can appear at the domain walls separating two distinct regions with imperfect rhombohedral stacking configurations. Based on a tight-binding formulation with distant hopping terms between carbon atoms, we first show that topologically distinct domains characterized by the valley Chern number are separated by a metallic region connecting AA and AA' stacking line in the layer translation vector space. We find that gapless states appear at the interface between the two stacking faulted domains with different layer translation or with opposite perpendicular electric field if their valley Chern numbers are different.

  15. Gaseous and particulate emissions from thermal power plants operating on different technologies.

    PubMed

    Athar, Makshoof; Ali, Mahboob; Khan, Misbahul Ain

    2010-07-01

    This paper presents the assessment of gaseous and particulate emissions from thermal power plants operating on different combustion technologies. Four thermal power plants operating on heavy furnace oil were selected for the study, among which three were based on diesel engine technology, while the fourth plant was based on oil-fired steam turbine technology. The stack emissions were monitored for critical air pollutants carbon monoxide, carbon dioxide, oxides of nitrogen, sulfur dioxide, particulate matter, lead, and mercury. The pollutant emissions were measured at optimum load conditions for a period of 6 months with an interval of 1 month. The results of stack emissions were compared with National Environmental Quality Standards of Pakistan and World Bank guidelines for thermal power plants, and few parameters were found higher than the permissible limits of emissions. It was observed that the emissions carbon monoxide, oxides of nitrogen, and particulate matters from diesel engine-based power plants were comparatively higher than the turbine-based power plants. The emissions of sulfur dioxide were high in all the plants, even the plants with different technologies, which was mainly due to high sulfur contents in fuel.

  16. TEST RESULTS OF HIGH TEMPERATURE STEAM/CO2 CO-ELECTROLYSIS IN A 10-CELL STACK

    SciTech Connect

    James E. O'Brien; Joseph J. Hartvigsen

    2007-06-01

    High temperature coelectrolysis experiments with CO2 / H2O mixtures were performed in a 10-cell planar solid oxide stack. Results indicated that stack apparent ASR values were shown not to vary significantly between pure steam electrolysis and steam / CO2 coelectrolysis values. Product gas compositions measured via an online micro gas chromatograph (GC) showed excellent agreement to predictions obtained from a chemical equilibrium coelectrolysis model developed for this study. Experimentally determined open cell potentials and thermal neutral voltages for coelectrolysis compared favorably to predictions obtained from a chemical equilibrium coelectrolysis and energy balance model, also developed for this study.

  17. Arrays of stacked metal coordination compounds

    DOEpatents

    Bulkowski, John E.

    1986-01-01

    A process is disclosed for preparing novel arrays of metal coordination compounds characterized by arrangement of the metal ions, separated by a linking agent, in stacked order one above the other. The process permits great flexibility in the design of the array. For example, layers of different composition can be added to the array at will.

  18. 49 CFR 178.606 - Stacking test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... converts the static load of the stacking test into a load suitable for dynamic compression testing. 2.2 is...)(1) of this subpart; or (ii) The packaging may be tested using a dynamic compression testing machine... transportation. For the dynamic compression test, a container passes the test if, after application of...

  19. 49 CFR 178.606 - Stacking test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... converts the static load of the stacking test into a load suitable for dynamic compression testing. 2.2 is...)(1) of this subpart; or (ii) The packaging may be tested using a dynamic compression testing machine... transportation. For the dynamic compression test, a container passes the test if, after application of...

  20. Explosive demolition of K East Reactor Stack

    SciTech Connect

    2010-07-26

    Using $420,000 in Recovery Act funds, the Department of Energy and contractor CH2M HILL Plateau Remediation Company topped off four months of preparations when they safely demolished the exhaust stack at the K East Reactor and equipment inside the reactor building on July 23, 2010.

  1. 49 CFR 178.815 - Stacking test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... test IBC; (ii) The calculated superimposed test load weight loaded on either a flat plate or a... their base on level, hard ground and subjected to a uniformly distributed superimposed test load for a..., 11HH2, 21HH1, 21HH2, 31HH1 and 31HH2) which bear the stacking load must be subjected to the test for...

  2. 49 CFR 178.815 - Stacking test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... test IBC; (ii) The calculated superimposed test load weight loaded on either a flat plate or a... their base on level, hard ground and subjected to a uniformly distributed superimposed test load for a..., 11HH2, 21HH1, 21HH2, 31HH1 and 31HH2) which bear the stacking load must be subjected to the test for...

  3. 49 CFR 178.980 - Stacking test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... of their capacity and to their maximum net mass, with the load being evenly distributed. (c) Test... uniformly distributed superimposed test load for a period of at least five minutes (see paragraph (c)(5) of.... (3) Rigid plastic Large Packagings which bear the stacking load must be subjected to the test for...

  4. 49 CFR 178.980 - Stacking test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... of their capacity and to their maximum net mass, with the load being evenly distributed. (c) Test... uniformly distributed superimposed test load for a period of at least five minutes (see paragraph (c)(5) of.... (3) Rigid plastic Large Packagings which bear the stacking load must be subjected to the test for...

  5. 49 CFR 178.815 - Stacking test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... test IBC; (ii) The calculated superimposed test load weight loaded on either a flat plate or a... their base on level, hard ground and subjected to a uniformly distributed superimposed test load for a..., 11HH2, 21HH1, 21HH2, 31HH1 and 31HH2) which bear the stacking load must be subjected to the test for...

  6. 49 CFR 178.980 - Stacking test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of their capacity and to their maximum net mass, with the load being evenly distributed. (c) Test... uniformly distributed superimposed test load for a period of at least five minutes (see paragraph (c)(5) of.... (3) Rigid plastic Large Packagings which bear the stacking load must be subjected to the test for...

  7. 49 CFR 178.980 - Stacking test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... subjected to a uniformly distributed superimposed test load for a period of at least five minutes (see... test for 28 days at 40 °C (104 °F). (4) For all Large Packagings, the load must be applied by one of... permissible gross mass and stacked on the test Large Packaging; (ii) The calculated superimposed test...

  8. 40 CFR 61.53 - Stack sampling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Mercury § 61.53 Stack sampling. (a) Mercury ore processing facility. (1) Unless a waiver of emission testing is obtained under § 61.13, each owner or operator processing mercury ore shall test emissions from the source...

  9. 40 CFR 61.53 - Stack sampling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Mercury § 61.53 Stack sampling. (a) Mercury ore processing facility. (1) Unless a waiver of emission testing is obtained under § 61.13, each owner or operator processing mercury ore shall test emissions from the source...

  10. Explosive demolition of K East Reactor Stack

    ScienceCinema

    None

    2016-07-12

    Using $420,000 in Recovery Act funds, the Department of Energy and contractor CH2M HILL Plateau Remediation Company topped off four months of preparations when they safely demolished the exhaust stack at the K East Reactor and equipment inside the reactor building on July 23, 2010.

  11. Average Transmission Probability of a Random Stack

    ERIC Educational Resources Information Center

    Lu, Yin; Miniatura, Christian; Englert, Berthold-Georg

    2010-01-01

    The transmission through a stack of identical slabs that are separated by gaps with random widths is usually treated by calculating the average of the logarithm of the transmission probability. We show how to calculate the average of the transmission probability itself with the aid of a recurrence relation and derive analytical upper and lower…

  12. 49 CFR 178.606 - Stacking test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... with specific gravities different from that of the liquid to be transported, the force must be calculated based on the specific gravity that will be marked on the packaging. The minimum height of the... number of containers that, when stacked, reach a height of 3 meters. s = specific gravity of lading....

  13. Arrays of stacked metal coordination compounds

    DOEpatents

    Bulkowski, J.E.

    1986-10-21

    A process is disclosed for preparing novel arrays of metal coordination compounds characterized by arrangement of the metal ions, separated by a linking agent, in stacked order one above the other. The process permits great flexibility in the design of the array. For example, layers of different composition can be added to the array at will. 3 figs.

  14. Removing Sulphur Dioxide From Stack Gases

    ERIC Educational Resources Information Center

    Slack, A. V.

    1973-01-01

    Process types, process concepts, claims and counterclaims, cost factors, and the level of developed technology for sulfur dioxide control in stack gases are focused upon and evaluated. Wet and dry processes as well as recovery and throwaway processes are compared. (BL)

  15. Filtration of Carbon Particulate Emissions from a Plasma Pyrolysis Assembly

    NASA Technical Reports Server (NTRS)

    Agui, Juan H.; Green, Robert; Vijayakumar, R.; Berger, Gordon; Greenwood, Zach; Abney, Morgan; Peterson, Elspeth

    2016-01-01

    NASA is investigating plasma pyrolysis as a candidate technology that will enable the recovery of hydrogen from the methane produced by the ISS Sabatier Reactor. The Plasma Pyrolysis Assembly (PPA) is the current prototype of this technology which converts the methane product from the Carbon Dioxide Reduction Assembly (CRA) to acetylene and hydrogen with 90% or greater conversion efficiency. A small amount of solid carbon particulates are generated as a side product and must be filtered before the acetylene is removed and the hydrogen-rich gas stream is recycled back to the CRA. We discuss developmental work on several options for filtering out the carbon particulate emissions from the PPA exit gas stream. The filtration technologies and concepts investigated range from fibrous media to monolithic ceramic and sintered metal media. This paper describes the different developed filter prototypes and characterizes their performance from integrated testing at the Environmental Chamber (E-Chamber) at MSFC. In addition, characterization data on the generated carbon particulates, that help to define filter requirements, are also presented.

  16. Dynamic model of a micro-tubular solid oxide fuel cell stack including an integrated cooling system

    NASA Astrophysics Data System (ADS)

    Hering, Martin; Brouwer, Jacob; Winkler, Wolfgang

    2017-02-01

    A novel dynamic micro-tubular solid oxide fuel cell (MT-SOFC) and stack model including an integrated cooling system is developed using a quasi three-dimensional, spatially resolved, transient thermodynamic, physical and electrochemical model that accounts for the complex geometrical relations between the cells and cooling-tubes. The modeling approach includes a simplified tubular geometry and stack design including an integrated cooling structure, detailed pressure drop and gas property calculations, the electrical and physical constraints of the stack design that determine the current, as well as control strategies for the temperature. Moreover, an advanced heat transfer balance with detailed radiative heat transfer between the cells and the integrated cooling-tubes, convective heat transfer between the gas flows and the surrounding structures and conductive heat transfer between the solid structures inside of the stack, is included. The detailed model can be used as a design basis for the novel MT-SOFC stack assembly including an integrated cooling system, as well as for the development of a dynamic system control strategy. The evaluated best-case design achieves very high electrical efficiency between around 75 and 55% in the entire power density range between 50 and 550 mW /cm2 due to the novel stack design comprising an integrated cooling structure.

  17. FEASIBILITY OF A STACK INTEGRATED SOFC OPTICAL CHEMICAL SENSOR

    SciTech Connect

    Michael A. Carpenter

    2004-03-30

    The work performed during the UCR Innovative Concepts phase I program was designed to demonstrate the chemical sensing capabilities of nano-cermet SPR bands at solid oxide fuel cell operating conditions. Key to this proposal is that the materials choice used a YSZ ceramic matrix which upon successful demonstration of this concept, will allow integration directly onto the SOFC stack. Under the Innovative Concepts Program the University at Albany Institute for Materials (UAIM)/UAlbany School of NanoSciences and NanoEngineering synthesized, analyzed and tested Pa, and Au doped YSZ nano-cermets as a function of operating temperature and target gas exposure (hydrogen, carbon monoxide and 1-dodecanethiol). During the aforementioned testing procedure the optical characteristics of the nano-cermets were monitored to determine the sensor selectivity and sensitivity.

  18. Fade to Green: A Biodegradable Stack of Microbial Fuel Cells.

    PubMed

    Winfield, Jonathan; Chambers, Lily D; Rossiter, Jonathan; Stinchcombe, Andrew; Walter, X Alexis; Greenman, John; Ieropoulos, Ioannis

    2015-08-24

    The focus of this study is the development of biodegradable microbial fuel cells (MFCs) able to produce useful power. Reactors with an 8 mL chamber volume were designed using all biodegradable products: polylactic acid for the frames, natural rubber as the cation-exchange membrane and egg-based, open-to-air cathodes coated with a lanolin gas diffusion layer. Forty MFCs were operated in various configurations. When fed with urine, the biodegradable stack was able to power appliances and was still operational after six months. One useful application for this truly sustainable MFC technology includes onboard power supplies for biodegradable robotic systems. After operation in remote ecological locations, these could degrade harmlessly into the surroundings to leave no trace when the mission is complete.

  19. 3-D CFD MODEL OF A MULTI-CELL HIGH TEMPERATURE ELECTROLYSIS STACK

    SciTech Connect

    Grant Hawkes; James O'Brien; Carl Stoots; Brian Hawkes

    2009-05-01

    A three-dimensional computational fluid dynamics (CFD) electrochemical model has been created to model high-temperature electrolysis stack performance and steam electrolysis in the Idaho National Laboratory (INL) Integrated Lab Scale (ILS) experiment. The model is made of 60 planar cells stacked on top of each other operated as Solid Oxide Electrolysis Cells (SOEC). Details of the model geometry are specific to a stack that was fabricated by Ceramatec, Inc. and tested at INL. Inlet and outlet plenum flow and distribution are considered. Mass, momentum, energy, and species conservation and transport are provided via the core features of the commercial CFD code FLUENT. A solid-oxide fuel cell (SOFC) model adds the electrochemical reactions and loss mechanisms and computation of the electric field throughout the cell. The FLUENT SOFC user defined subroutine was modified for this work to allow for operation in the SOEC mode. Model results provide detailed profiles of temperature, Nernst potential, operating potential, activation over-potential, anode-side gas composition, cathode-side gas composition, current density, and hydrogen production over a range of stack operating conditions. Variations in flow distribution and species concentration are discussed. End effects of flow and per-cell voltage are also considered.

  20. Polarization signatures of airborne particulates

    NASA Astrophysics Data System (ADS)

    Raman, Prashant; Fuller, Kirk A.; Gregory, Don A.

    2013-07-01

    Exploratory research has been conducted with the aim of completely determining the polarization signatures of selected particulates as a function of wavelength. This may lead to a better understanding of the interaction between electromagnetic radiation and such materials, perhaps leading to the point detection of bio-aerosols present in the atmosphere. To this end, a polarimeter capable of measuring the complete Mueller matrix of highly scattering samples in transmission and reflection (with good spectral resolution from 300 to 1100 nm) has been developed. The polarization properties of Bacillus subtilis (surrogate for anthrax spore) are compared to ambient particulate matter species such as pollen, dust, and soot. Differentiating features in the polarization signatures of these samples have been identified, thus demonstrating the potential applicability of this technique for the detection of bio-aerosol in the ambient atmosphere.

  1. Particulate problem solutions for rod pumped producing wells

    SciTech Connect

    Williams, S.J.

    1995-12-31

    Sand and other fluid entrained particulates can cause substantial operational problems for rod pumped producing wells. These problems take the form of down-hole pump wear, plunger sticking, and/or catastrophic breakage of pump components. A six year study of 600+ pump investigations shows that problems with particulates account for a substantial number of the total barrel and plunger failures. Many of these failures could have been avoided through the proper application of API and special pump designs as well as certain choices of pump variables. These pump variables and designs will be addressed along with operating parameters. How hard is sand? How large is it? Should plunger and barrel choices take these variables into account? Also, metal plungers must {open_quotes}slip{close_quotes} fluid for proper lubrication. Too much slippage leads to pump inefficiencies. However, down-hole pump efficiencies based on slippage need to be balanced against pump longevity due to proper selection for particulate production. Some time-proven rules of thumb can be applied to make these choices, and an included chart will make plunger slippage calculations simple and straightforward. Scale which sticks to pump surfaces dictates the choice of a different style down-hole pump. A straight-forward modification of an RH style API pump has proved successful in these conditions. Fluid and particulate production with and without attendant gas production requires a different approach to down-hole pump selection. Several successful older pump designs as well as some recently proven new designs will be described. A test program has been completed and actual applications have shown that an API Tubing Pump derivative can pump large volumes of particulate laden fluid without characteristic sticking of the plunger.

  2. Comparative analysis between the alveolar recruitment maneuver and breath stacking technique in patients with acute lung injury

    PubMed Central

    Porto, Elias Ferreira; Tavolaro, Kelly Cristiani; Kumpel, Claudia; Oliveira, Fernanda Augusta; Sousa, Juciaria Ferreira; de Carvalho, Graciele Vieira; de Castro, Antonio Adolfo Mattos

    2014-01-01

    Objective To compare the effectiveness of the alveolar recruitment maneuver and the breath stacking technique with respect to lung mechanics and gas exchange in patients with acute lung injury. Methods Thirty patients were distributed into two groups: Group 1 - breath stacking; and Group 2 - alveolar recruitment maneuver. After undergoing conventional physical therapy, all patients received both treatments with an interval of 1 day between them. In the first group, the breath stacking technique was used initially, and subsequently, the alveolar recruitment maneuver was applied. Group 2 patients were initially subjected to alveolar recruitment, followed by the breath stacking technique. Measurements of lung compliance and airway resistance were evaluated before and after the use of both techniques. Gas analyses were collected before and after the techniques were used to evaluate oxygenation and gas exchange. Results Both groups had a significant increase in static compliance after breath stacking (p=0.021) and alveolar recruitment (p=0.03), but with no significant differences between the groups (p=0.95). The dynamic compliance did not increase for the breath stacking (p=0.22) and alveolar recruitment (p=0.074) groups, with no significant difference between the groups (p=0.11). The airway resistance did not decrease for either groups, i.e., breath stacking (p=0.91) and alveolar recruitment (p=0.82), with no significant difference between the groups (p=0.39). The partial pressure of oxygen increased significantly after breath stacking (p=0.013) and alveolar recruitment (p=0.04), but there was no significant difference between the groups (p=0.073). The alveolar-arterial O2 difference decreased for both groups after the breath stacking (p=0.025) and alveolar recruitment (p=0.03) interventions, and there was no significant difference between the groups (p=0.81). Conclusion Our data suggest that the breath stacking and alveolar recruitment techniques are effective in

  3. Material Instabilities in Particulate Systems

    NASA Technical Reports Server (NTRS)

    Goddard, J. D.

    1999-01-01

    Following is a brief summary of a theoretical investigation of material (or constitutive) instability associated with shear induced particle migration in dense particulate suspensions or granular media. It is shown that one can obtain a fairly general linear-stability analysis, including the effects of shear-induced anisotropy in the base flow as well as Reynolds dilatancy. A criterion is presented here for simple shearing instability in the absence of inertia and dilatancy.

  4. SOUTHERN FINE PARTICULATE MONITORING PROJECT

    SciTech Connect

    Ashley D. Williamson

    2001-07-01

    This is the third quarterly progress report of the ''Southern Fine Particulate Monitoring Project'', funded by the U.S. Department of Energy's National Energy Technology Laboratory under DOE Cooperative Agreement No. DE-FC26-00NT40770 to Southern Research Institute (SRI). In this two year project SRI will conduct detailed studies of ambient fine particulate matter in the Birmingham, AL metropolitan area. Project objectives include: Augment existing measurements of primary and secondary aerosols at an established urban southeastern monitoring site; Make a detailed database of near-continuous measurements of the time variation of fine particulate mass, composition, and key properties (including particle size distribution); Apply the measurements to source attribution, time/transport properties of fine PM, and implications for management strategies for PM{sub 2.5}; and Validate and compare key measurement methods used in this study for applicability within other PM{sub 2.5} research by DOE-FE, EPA, NARSTO, and others. During the third project quarter, the new SRI air monitoring shelter and additional instruments were installed at the site. Details include: Installation of Radiance Research M903 Nephelometer; Installation of SRI air monitoring shelter at North Birmingham Site; Relocation of instruments from SEARCH shelter to SRI shelter; Installation of Rupprecht & Patashnick 8400 Sulfate Monitor; Assembly and initial laboratory testing for particulate sulfate monitor of Harvard design; Efficiency testing of particle sizing instrument package at SRI lab; Preparation for the Eastern Supersite July measurement intensive program; and Continued monitoring with TEOM and particle sizing instruments.

  5. Gaseous and particulate emissions from a DC arc melter.

    PubMed

    Overcamp, Thomas J; Speer, Matthew P; Griner, Stewart J; Cash, Douglas M

    2003-01-01

    Tests treating soils contaminated with metal compounds and radionuclide surrogates were conducted in a DC arc melter. The soil melted, and glassy or ceramic waste forms with a separate metal phase were produced. Tests were run in the melter plenum with either air or N2 purge gases. In addition to nitrogen, the primary emissions of gases were CO2, CO, oxygen, methane, and oxides of nitrogen (NO(x)). Although the gas flow through the melter was low, the particulate concentrations ranged from 32 to 145 g/m3. Cerium, a nonradioactive surrogate for plutonium and uranium, was not enriched in the particulate matter (PM). The PM was enriched in cesium and highly enriched in lead.

  6. Particulate gravity currents on Venus

    NASA Astrophysics Data System (ADS)

    Waltham, Dave; Pickering, Kevin T.; Bray, Veronica J.

    2008-02-01

    Canali are moderately sinuous channels, typically a few kilometers wide and hundreds of kilometers long, that occur principally on the plains of Venus. Plausible hypotheses for their formation include the following: open channels cut by exotic, low-viscosity lavas; roofed-over basaltic lava channels; or water on a cooler, wetter ancient Venus. Although it is accepted that a fluid cut these channels, none of these hypotheses are entirely satisfactory. It is therefore prudent to investigate other explanations. A particulate gravity current is a rapidly moving, sediment-laden flow that moves downslope as a result of its high density compared to the ambient fluid. This high density is produced by suspension of dense particles in a lower-density fluid. As these flows are largely driven by slope, rather than by momentum, they are potentially capable of traveling great distances, producing extensive channel systems. We apply this process to Venus, exploring its channel-forming potential via mathematical modeling and morphological comparison of submarine channels on Earth to canali on Venus. Results of our modeling show that atmospheric particulate gravity currents are physically and geologically plausible on Venus. The potential of this process to form channels of great length is such that particulate gravity currents can be considered as an alternate explanation for canali genesis.

  7. ADVANCED FLUE GAS CONDITIONING AS A RETROFIT UPGRADE TO ENHANCE PM COLLECTION FROM COAL-FIRED ELECTRIC UTILITY BOILERS

    SciTech Connect

    Kenneth E. Baldrey

    2003-02-01

    The U.S. Department of Energy and ADA Environmental Solutions are engaged in a project to develop commercial flue gas conditioning additives. The objective is to develop conditioning agents that can help improve particulate control performance of smaller or under-sized electrostatic precipitators on utility coal-fired boilers. The new chemicals will be used to control both the electrical resistivity and the adhesion or cohesivity of the fly ash. There is a need to provide cost-effective and safer alternatives to traditional flue gas conditioning with SO{sub 3} and ammonia. During this reporting quarter, two cohesivity-specific additive formulations, ADA-44C and ADA-51, were evaluated in a full-scale trial at the American Electric Power Conesville plant. Ammonia conditioning was also evaluated for comparison. ADA-51 and ammonia conditioning significantly reduced rapping and non-rapped particulate re-entrainment based on stack opacity monitor data. Based on the successful tests to date, ADA-51 will be evaluated in a long-term test.

  8. Determination of polycyclic aromatic hydrocarbons in diesel exhaust particulate matter and diesel fuel oil.

    PubMed

    Obuchi, A; Aoyama, H; Ohi, A; Ohuchi, H

    1984-11-16

    Clean-up procedures were developed for a method for determining the amount of polycyclic aromatic hydrocarbons (PAHs) in diesel exhaust particulate matter and in diesel fuel oils using reversed-phase high-performance liquid chromatography (HPLC). They were based mainly on the elimination of insoluble matter and aliphatic compounds that affect the performance of HPLC, from the dichloromethane extracts of particulate matter or from oils, with the aid of a disposable preparation column containing reversed-phase packings (Sep-Pak C18). Using these procedures, it is possible to detect 1 ng of benzo(a)pyrene in 30 mg of particulate matter with more than a 97% recovery or 0.5 ng in 50 microliters of oil with 91% recovery. Examples of analyses are given for particulate matter emitted from a diesel test engine and for diesel fuel oils, such as gas oil, residual oil and coal-liquefied oil.

  9. Computational model to predict thermal dynamics of planar solid oxide fuel cell stack during start-up process

    NASA Astrophysics Data System (ADS)

    Ki, Jeongpill; Kim, Daejong

    Solid oxide fuel cell (SOFC) systems have been recognized as the most advanced power generation system with the highest thermal efficiency with a compatibility with wide variety of hydrocarbon fuels, synthetic gas from coal, hydrogen, etc. However, SOFC requires high temperature operation to achieve high ion conductivity of ceramic electrolyte, and thus SOFC should be heated up first before fuel is supplied into the stack. This paper presents computational model for thermal dynamics of planar SOFC stack during start-up process. SOFC stack should be heated up as quickly as possible from ambient temperature to above 700 °C, while minimizing net energy consumption and thermal gradient during the heat up process. Both cathode and anode channels divided by current-collecting ribs were modeled as one-dimensional flow channels with multiple control volumes and all the solid structures were discretized into finite volumes. Two methods for stack-heating were investigated; one is with hot air through cathode channels and the other with electric heating inside a furnace. For the simulation of stack-heating with hot air, transient continuity, flow momentum, and energy equation were applied for discretized control volumes along the flow channels, and energy equations were applied to all the solid structures with appropriate heat transfer model with surrounding solid structures and/or gas channels. All transient governing equations were solved using a time-marching technique to simulate temporal evolution of temperatures of membrane-electrode-assembly (MEA), ribs, interconnects, flow channels, and solid housing structure located inside the insulating chamber. For electrical heating, uniform heat flux was applied to the stack surface with appropriate numerical control algorithm to maintain the surface temperature to certain prescribed value. The developed computational model provides very effective simulation tool to optimize stack-heating process minimizing net heating energy

  10. MERCURY CONTROL WITH THE ADVANCED HYBRID PARTICULATE COLLECTOR

    SciTech Connect

    Ye Zhuang; Stanley J. Miller; Grant E. Dunham; Michelle R. Olderbak

    2002-02-01

    Since 1995, DOE has supported development of a new concept in particulate control, called the advanced hybrid particulate collector (AHPC). 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 emission with conventional ESPs, and it solves the problem of reentrainment and re-collection of dust in conventional baghouses. The AHPC appears to have unique advantages for mercury control over baghouses or ESPs as an excellent gas-solid contactor. The objective of the three-task project is to demonstrate 90% total mercury control in the AHPC at a lower cost than current mercury control estimates. The approach includes bench-scale batch testing that ties the new work to previous results and links results with larger-scale pilot testing with real flue gas on a coal-fired combustion system, pilot-scale testing on a coal-fired combustion system with both a pulse-jet baghouse and an AHPC to prove or disprove the research hypotheses, and field demonstration pilot-scale testing at a utility power plant to prove scaleup and demonstrate longer-term mercury control. This project, if successful, will demonstrate at the pilot-scale level a technology that would provide a cost-effective technique to accomplish control of mercury emissions and, at the same time, greatly enhance fine particulate collection efficiency. The technology can be used to retrofit systems currently employing inefficient ESP technology as well as for new construction, thereby providing a solution to a large segment of the U.S. utility industry as well as other industries requiring mercury control.

  11. 40 CFR 52.2384 - Stack height review.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... affected by stack height credits greater than good engineering practice or any other prohibited dispersion... ‘good engineering practice’ stack height or from using ‘other dispersion techniques.’ ” Thus,...

  12. VIEW OF STACK WITH AUTOMOBILE AND TRACTOR REPAIR SHOP TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF STACK WITH AUTOMOBILE AND TRACTOR REPAIR SHOP TO THE FAR RIGHT. WAREHOUSE WITH ITS RIDGELINE ROTARY VENTS TO RIGHT OF STACK. VIEW FROM THE WEST - Kekaha Sugar Company, Sugar Mill Building, 8315 Kekaha Road, Kekaha, Kauai County, HI

  13. Potential radionuclide emissions from stacks on the Hanford site, Part 2: Dose assessment methodology using portable low-resolution gamma spectroscopy

    SciTech Connect

    Barnett, J.M.

    1995-02-01

    In September 1992, the Westinghouse Hanford Company began developing an in situ measurement method to assess gamma radiation emanating from high-efficiency particulate air filters using portable low-resolution gamma spectroscopy. The purpose of the new method was to assess radioactive exhaust stack air emissions from empirical data rather than from theoretical models and to determine the potential unabated dose to an offsite theoretical maximally exposed individual. In accordance with Title 40, Code of Federal Regulations, Part 61, Subpart H, {open_quotes}National Emission Standards for Hazardous Air Pollutants{close_quotes}, stacks that have the potential to emit {ge} 1 {mu}Sv y{sup {minus}1} (0.1 mrem y{sup {minus}1}) to the maximally exposed individual are considered {open_quotes}major{close_quotes} and must meet the continuous monitoring requirements. After the method was tested and verified, the U.S. Environmental Protection Agency, Region 10, approved its use in June 1993. Of the 125 stacks operated by the Westinghouse Hanford Company, 22 were targeted for evaluation by this method, and 15 were assessed. (The method could not be applied at seven stacks because of excessive background radiation or because no gamma emitting particles appear in the emission stream.) The most significant result from this study was the redesignation of the T Plant main stack. The stack was assessed as being {open_quotes}minor{close_quotes}, and it now only requires periodic confirmatory measurements and meets federally imposed sampling requirements.

  14. Mercury Control With The Advanced Hybrid Particulate Collector

    SciTech Connect

    Stanley J. Miller; Ye Zhuang; Jay C. Almlie

    2004-12-31

    This project was awarded under U.S. Department of Energy (DOE) National Energy Technology Laboratory Program Solicitation DE-FC26-01NT41184 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 included the Energy & Environmental Research Center 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 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 also appears to have unique advantages for mercury control over baghouses or ESPs as an excellent gas--solid contactor. The objective of the original five-task project was to demonstrate 90% total mercury control in the AHPC at a lower cost than current mercury control estimates. The approach included benchscale batch tests, larger-scale pilot testing with real flue gas on a coal-fired combustion system, and field demonstration at the 2.5-MW scale at a utility power plant to prove scale-up and demonstrate longer-term mercury control. The scope of work was modified to include an additional sixth task, initiated in April 2003. The objective of this task was to

  15. 40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 9 2014-07-01 2014-07-01 false How do I monitor the temperature of....15270 How do I monitor the temperature of flue gases at the inlet of my particulate matter control... temperature of the flue gas stream at the inlet of each particulate matter control device....

  16. 40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false How do I monitor the temperature of....15270 How do I monitor the temperature of flue gases at the inlet of my particulate matter control... temperature of the flue gas stream at the inlet of each particulate matter control device....

  17. 40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 9 2012-07-01 2012-07-01 false How do I monitor the temperature of....15270 How do I monitor the temperature of flue gases at the inlet of my particulate matter control... temperature of the flue gas stream at the inlet of each particulate matter control device....

  18. 40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 8 2011-07-01 2011-07-01 false How do I monitor the temperature of....15270 How do I monitor the temperature of flue gases at the inlet of my particulate matter control... temperature of the flue gas stream at the inlet of each particulate matter control device....

  19. 40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 9 2013-07-01 2013-07-01 false How do I monitor the temperature of....15270 How do I monitor the temperature of flue gases at the inlet of my particulate matter control... temperature of the flue gas stream at the inlet of each particulate matter control device....

  20. Adjustable cutting guide aligns and positions stacks of material

    NASA Technical Reports Server (NTRS)

    Thiel, A. M.

    1966-01-01

    Adjustable guide tool aligns and positions stacks of material for cutting at various angles. The device adapts its shape to stacks of any corner angle, adjusts to any cutting angle, and quickly aligns the stacks for repeated cutting. With this device, an operator need not place his hands under the knife during alignment.