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Brian K Gullett - One of the best experts on this subject based on the ideXlab platform.

  • pcdd f and aromatic emissions from simulated forest and grassland fires
    Atmospheric Environment, 2008
    Co-Authors: Brian K Gullett, Abderrahmane Touati, Lukas Oudejans
    Abstract:

    Abstract Emissions of Polychlorinated Dibenzodioxin and Polychlorinated dibenzofuran (PCDD/F) from simulated grassland and forest fires were quantitatively sampled to derive emission factors in support of PCDD/F inventory development. Grasses from Kentucky and Minnesota; forest shrubs from California and Florida; and pine forest biomass from the Piedmont region of North Carolina, western North Carolina, and coastal Oregon were collected and tested in a burn facility that mimicked a prescribed fire in the natural environment scenario. Ambient sampling methods for PCDD/F were variously accompanied by real-time measurements of major aromatic species, including benzene, toluene, naphthalene, and styrene. Emission factors in mass of toxic equivalent (TEQ) of PCDD/F per kg of carbon burned (kgCb) for the two grasses averaged 0.32 ng TEQ/kgCb. Burn tests (n = 27) on forest biomass from the five sources show PCDD/F emission factors ranging from 0.3 to 26.3 ng TEQ/kgCb, with a mean and median of 5.8 and 3.3 ng TEQ/kgCb, respectively. Variation of the forest green/brown needle content, sample size, burn scenario, and facility ventilation rate showed no consistent effects on PCDD/F emissions. For forest burns, 30–35% of the PCDD and 50-55% of the PCDF emissions occurred during the flaming period from 0 to 5 min, while the highest emission factors (per mass of carbon burned) were recorded during the smoldering period from 5 to 60 min. Emissions of PCDD/F exceeded those present in the raw biomass by a factor of four, confirming PCDD/F formation from combustion rather than from simple surface volatilization. The majority of the PCDD/F partitions to the emissions rather than the ash.

  • PCDD/F and aromatic emissions from simulated forest and grassland fires
    Atmospheric Environment, 2008
    Co-Authors: Brian K Gullett, Abderrahmane Touati, Lukas Oudejans
    Abstract:

    Abstract Emissions of Polychlorinated Dibenzodioxin and Polychlorinated dibenzofuran (PCDD/F) from simulated grassland and forest fires were quantitatively sampled to derive emission factors in support of PCDD/F inventory development. Grasses from Kentucky and Minnesota; forest shrubs from California and Florida; and pine forest biomass from the Piedmont region of North Carolina, western North Carolina, and coastal Oregon were collected and tested in a burn facility that mimicked a prescribed fire in the natural environment scenario. Ambient sampling methods for PCDD/F were variously accompanied by real-time measurements of major aromatic species, including benzene, toluene, naphthalene, and styrene. Emission factors in mass of toxic equivalent (TEQ) of PCDD/F per kg of carbon burned (kgCb) for the two grasses averaged 0.32 ng TEQ/kgCb. Burn tests (n = 27) on forest biomass from the five sources show PCDD/F emission factors ranging from 0.3 to 26.3 ng TEQ/kgCb, with a mean and median of 5.8 and 3.3 ng TEQ/kgCb, respectively. Variation of the forest green/brown needle content, sample size, burn scenario, and facility ventilation rate showed no consistent effects on PCDD/F emissions. For forest burns, 30–35% of the PCDD and 50-55% of the PCDF emissions occurred during the flaming period from 0 to 5 min, while the highest emission factors (per mass of carbon burned) were recorded during the smoldering period from 5 to 60 min. Emissions of PCDD/F exceeded those present in the raw biomass by a factor of four, confirming PCDD/F formation from combustion rather than from simple surface volatilization. The majority of the PCDD/F partitions to the emissions rather than the ash.

  • emissions of pcdd f from uncontrolled domestic waste burning
    Chemosphere, 2001
    Co-Authors: Brian K Gullett, Paul M. Lemieux, Christopher C. Lutes, Chris K. Winterrowd, Dwain Winters
    Abstract:

    Abstract Emissions of Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) result from inefficiencies of combustion processes, most typically waste combustion. Uncontrolled combustion, such as occurs during so-called “backyard burning” of domestic waste, may therefore produce optimal conditions for formation and emission of PCDD/F. However, few assessments of PCDD/F emissions are available from these sources. This work describes the first known comprehensive assessment of PCDD/F emissions from uncontrolled, domestic waste burning. Emissions were copious, but highly variable, ranging over several orders of magnitude. The potential for emissions appears to be related primarily to combustion parameters and concentrations of various gas-phase species, the latter which may be affected by changes in waste composition, waste orientation, and/or combustion conditions.

  • Emissions of PCDD/F from uncontrolled, domestic waste burning
    Chemosphere, 2001
    Co-Authors: Brian K Gullett, Paul M. Lemieux, Christopher C. Lutes, Chris K. Winterrowd, Dwain Winters
    Abstract:

    Abstract Emissions of Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) result from inefficiencies of combustion processes, most typically waste combustion. Uncontrolled combustion, such as occurs during so-called “backyard burning” of domestic waste, may therefore produce optimal conditions for formation and emission of PCDD/F. However, few assessments of PCDD/F emissions are available from these sources. This work describes the first known comprehensive assessment of PCDD/F emissions from uncontrolled, domestic waste burning. Emissions were copious, but highly variable, ranging over several orders of magnitude. The potential for emissions appears to be related primarily to combustion parameters and concentrations of various gas-phase species, the latter which may be affected by changes in waste composition, waste orientation, and/or combustion conditions.

  • formation of chlorinated dioxins and furans in a hazardous waste firing industrial boiler
    Environmental Science & Technology, 2000
    Co-Authors: Brian K Gullett, And Abderrahmane Touati
    Abstract:

    This research examined the potential for emissions of Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) from industrial boilers that cofire hazardous waste. PCDD/F emissions were sampled from a 732 kW (2.5 × 106 Btu/h), 3-pass, firetube boiler using #2 fuel oil cofired with 2,4-dichlorophenol or 1,2-dichlorobenzene and a copper naphthenate mixture. PCDD/F levels were significantly elevated when improved combustion conditions (reduced carbon monoxide, increased carbon dioxide) followed periods of flame wall-impingement and soot formation/deposition on the boiler tubes. Boiler tube deposits became a sink and source for PCDD/F reactants (copper and chlorine) and PCDD/F, resulting in continued formation and emissions long after waste cofiring ceased. The role of deposits in PCDD/F formation makes emissions dependent on current as well as previous firing conditions, resulting in uncertainty regarding prediction of emissions based solely on the type and rate of cofired hazardous waste.

Gerard Cornelissen - One of the best experts on this subject based on the ideXlab platform.

  • a large scale field trial of thin layer capping of pcdd f contaminated sediments sediment to water fluxes up to 5 years post amendment
    Integrated Environmental Assessment and Management, 2016
    Co-Authors: Gerard Cornelissen, Morten Schaanning, Jonas S Gunnarsson, Espen Eek
    Abstract:

    The longer-term effect (3–5 y) of thin-layer capping on in situ sediment-to-surface water fluxes was monitored in a large-scale field experiment in the Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) contaminated Grenlandfjords, Norway (4 trial plots of 10 000 to 40 000 m2 at 30 to 100 m water depth). Active caps (designed thickness 2.5 cm) were established in 2 fjords, consisting of dredged clean clay amended with powdered activated carbon (PAC) from anthracite. These active caps were compared to 2 nonactive caps in one of the fjords (designed thickness 5 cm) consisting of either clay only (i.e., without PAC) or crushed limestone. Sediment-to-water PCDD/F fluxes were measured in situ using diffusion chambers. An earlier study showed that during the first 2 years after thin-layer capping, flux reductions relative to noncapped reference fields were more extensive at the fields capped with nonactive caps (70%–90%) than at the ones with PAC-containing caps (50%–60%). However, the present work shows that between 3 and 5 years after thin-layer capping, this trend was reversed and cap effectiveness in reducing fluxes was increasing to 80% to 90% for the PAC caps, whereas cap effectiveness of the nonactive caps decreased to 20% to 60%. The increasing effectiveness over time of PAC-containing “active“ caps is explained by a combination of slow sediment-to-PAC mass transfer of PCDD/Fs and bioturbation by benthic organisms. The decreasing effectiveness of “nonactive“ limestone and clay caps is explained by deposition of contaminated particles on top of the caps. The present field data indicate that the capping efficiency of thin active caps (i.e., enriched with PAC) can improve over time as a result of slow diffusive PCDD/F transfer from sediment to PAC particles and better mixing of the PAC by bioturbation. Integr Environ Assess Manag 2015;X:000–000. © 2015 SETAC

  • large scale field study on thin layer capping of marine pcdd f contaminated sediments in grenlandfjords norway physicochemical effects
    Environmental Science & Technology, 2012
    Co-Authors: Gerard Cornelissen, Katja Amstaetter, Audun Hauge, Morten Schaanning, Bjornar Beylich, Jonas S Gunnarsson, Gijs D Breedveld, Amy M P Oen, Espen Eek
    Abstract:

    A large-scale field experiment on in situ thin-layer capping was carried out in the Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) contaminated Grenlandsfjords, Norway. The main focus of the trial was to test the effectiveness of active caps (targeted thickness of 2.5 cm) consisting of powdered activated carbon (AC) mixed into locally dredged clean clay. Nonactive caps (targed thickness of 5 cm) consisting of clay without AC as well as crushed limestone were also tested. Fields with areas of 10 000 to 40 000 m2 were established at 30 to 100 m water depth. Auxiliary shaken laboratory batch experiments showed that 2% of the applied powdered AC substantially reduced PCDD/F porewater concentrations, by >90% for tetra-, penta- and hexa-clorinated congeners to 60–70% for octachlorinated ones. In-situ AC profiles revealed that the AC was mixed into the sediment to 3 to 5 cm depth in 20 months. Only around 25% of the AC was found inside the pilot fields. Sediment-to-water PCDD/F fluxes measured by in sit...

  • Large-Scale Field Study on Thin-Layer Capping of Marine PCDD/F-Contaminated Sediments in Grenlandfjords, Norway: Physicochemical Effects
    2012
    Co-Authors: Gerard Cornelissen, Katja Amstaetter, Audun Hauge, Morten Schaanning, Bjornar Beylich, Gijs D Breedveld, Amy M P Oen, Jonas S. Gunnarsson, Espen Eek
    Abstract:

    A large-scale field experiment on in situ thin-layer capping was carried out in the Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) contaminated Grenlandsfjords, Norway. The main focus of the trial was to test the effectiveness of active caps (targeted thickness of 2.5 cm) consisting of powdered activated carbon (AC) mixed into locally dredged clean clay. Nonactive caps (targed thickness of 5 cm) consisting of clay without AC as well as crushed limestone were also tested. Fields with areas of 10 000 to 40 000 m2 were established at 30 to 100 m water depth. Auxiliary shaken laboratory batch experiments showed that 2% of the applied powdered AC substantially reduced PCDD/F porewater concentrations, by >90% for tetra-, penta- and hexa-clorinated congeners to 60–70% for octachlorinated ones. In-situ AC profiles revealed that the AC was mixed into the sediment to 3 to 5 cm depth in 20 months. Only around 25% of the AC was found inside the pilot fields. Sediment-to-water PCDD/F fluxes measured by in situ diffusion chambers were significantly lower at the capped fields than at reference fields in the same fjord, reductions being largest for the limestone (50–90%) followed by clay (50–70%), and the AC + clay (60%). Also reductions in overlying aqueous PCDD/F concentrations measured by passive samplers were significant in most cases (20–40% reduction), probably because of the large size of the trial fields.The AC was less effective in the field than in the laboratory, probably due to prolonged sediment-to-AC mass transfer times for PCDD/Fs and field factors such as integrity of the cap, new deposition of contaminated sediment particles, and bioturbation. The present field data indicate that slightly thicker layers of limestone and dredged clay can show as good physicochemical effectiveness as thin caps of AC mixed with clay, at least for PCDD/Fs during the first two years after cap placement

  • Freely dissolved PCDD/F concentrations in the Frierfjord, Norway: comparing equilibrium passive sampling with “active” water sampling
    Journal of Soils and Sediments, 2010
    Co-Authors: Gerard Cornelissen, Dag Broman, Kristoffer Næs
    Abstract:

    Introduction Equilibrium passive samplers consisting of 55-µm polyoxymethylene (POM) and 170-µm polydimethylsiloxane were tested for the analysis of Polychlorinated Dibenzodioxin/furan (PCDD/F) in the pore water and overlying water of the Frierfjord, a bay in southern Norway. This fjord is heavily polluted with PCDD/Fs due to emissions from a former Mg smelter. Results and Discussion Field exposures of both equilibrium passive sampler types yielded similar results for freely dissolved PCDD/F concentrations ( C _W,free) in the overlying water. In addition, the passive sampling data deviated less than an order of magnitude from C _W,free obtained with conventional “active” sampling through pumping/filtration over glass fiber filters and polyurethane foam. A similar comparison was done for the pore water, where POM passive samplers also proved to yield freely dissolved pore water concentrations ( C _PW,free) that deviated less than an order of magnitude from earlier published values measured by direct pore water extraction. The data were also used to derive sediment–water activity ratios, which indicate the diffusive flux direction. High sediment-to-water activity ratios (median value of 160 for 17 congeners) indicated a strong diffusion gradient between the sediment pore water and the overlying water, probably due to deposition of particle-bound PCDD/Fs in combination with low sedimentation rates.

  • Freely dissolved PCDD/F concentrations in the Frierfjord, Norway: comparing equilibrium passive sampling with “active” water sampling
    Journal of Soils and Sediments, 2009
    Co-Authors: Gerard Cornelissen, Dag Broman, Kristoffer Næs
    Abstract:

    Introduction Equilibrium passive samplers consisting of 55-µm polyoxymethylene (POM) and 170-µm polydimethylsiloxane were tested for the analysis of Polychlorinated Dibenzodioxin/furan (PCDD/F) in the pore water and overlying water of the Frierfjord, a bay in southern Norway. This fjord is heavily polluted with PCDD/Fs due to emissions from a former Mg smelter.

Dwain Winters - One of the best experts on this subject based on the ideXlab platform.

  • emissions of pcdd f from uncontrolled domestic waste burning
    Chemosphere, 2001
    Co-Authors: Brian K Gullett, Paul M. Lemieux, Christopher C. Lutes, Chris K. Winterrowd, Dwain Winters
    Abstract:

    Abstract Emissions of Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) result from inefficiencies of combustion processes, most typically waste combustion. Uncontrolled combustion, such as occurs during so-called “backyard burning” of domestic waste, may therefore produce optimal conditions for formation and emission of PCDD/F. However, few assessments of PCDD/F emissions are available from these sources. This work describes the first known comprehensive assessment of PCDD/F emissions from uncontrolled, domestic waste burning. Emissions were copious, but highly variable, ranging over several orders of magnitude. The potential for emissions appears to be related primarily to combustion parameters and concentrations of various gas-phase species, the latter which may be affected by changes in waste composition, waste orientation, and/or combustion conditions.

  • Emissions of PCDD/F from uncontrolled, domestic waste burning
    Chemosphere, 2001
    Co-Authors: Brian K Gullett, Paul M. Lemieux, Christopher C. Lutes, Chris K. Winterrowd, Dwain Winters
    Abstract:

    Abstract Emissions of Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) result from inefficiencies of combustion processes, most typically waste combustion. Uncontrolled combustion, such as occurs during so-called “backyard burning” of domestic waste, may therefore produce optimal conditions for formation and emission of PCDD/F. However, few assessments of PCDD/F emissions are available from these sources. This work describes the first known comprehensive assessment of PCDD/F emissions from uncontrolled, domestic waste burning. Emissions were copious, but highly variable, ranging over several orders of magnitude. The potential for emissions appears to be related primarily to combustion parameters and concentrations of various gas-phase species, the latter which may be affected by changes in waste composition, waste orientation, and/or combustion conditions.

Chris K. Winterrowd - One of the best experts on this subject based on the ideXlab platform.

  • emissions of pcdd f from uncontrolled domestic waste burning
    Chemosphere, 2001
    Co-Authors: Brian K Gullett, Paul M. Lemieux, Christopher C. Lutes, Chris K. Winterrowd, Dwain Winters
    Abstract:

    Abstract Emissions of Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) result from inefficiencies of combustion processes, most typically waste combustion. Uncontrolled combustion, such as occurs during so-called “backyard burning” of domestic waste, may therefore produce optimal conditions for formation and emission of PCDD/F. However, few assessments of PCDD/F emissions are available from these sources. This work describes the first known comprehensive assessment of PCDD/F emissions from uncontrolled, domestic waste burning. Emissions were copious, but highly variable, ranging over several orders of magnitude. The potential for emissions appears to be related primarily to combustion parameters and concentrations of various gas-phase species, the latter which may be affected by changes in waste composition, waste orientation, and/or combustion conditions.

  • Emissions of PCDD/F from uncontrolled, domestic waste burning
    Chemosphere, 2001
    Co-Authors: Brian K Gullett, Paul M. Lemieux, Christopher C. Lutes, Chris K. Winterrowd, Dwain Winters
    Abstract:

    Abstract Emissions of Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) result from inefficiencies of combustion processes, most typically waste combustion. Uncontrolled combustion, such as occurs during so-called “backyard burning” of domestic waste, may therefore produce optimal conditions for formation and emission of PCDD/F. However, few assessments of PCDD/F emissions are available from these sources. This work describes the first known comprehensive assessment of PCDD/F emissions from uncontrolled, domestic waste burning. Emissions were copious, but highly variable, ranging over several orders of magnitude. The potential for emissions appears to be related primarily to combustion parameters and concentrations of various gas-phase species, the latter which may be affected by changes in waste composition, waste orientation, and/or combustion conditions.

  • PCDD/F emissions from uncontrolled, domestic waste burning. Presented at Dioxin ’00
    2000
    Co-Authors: Brian K Gullett, Paul M. Lemieux, Christopher C. Lutes, Chris K. Winterrowd, Dwain L
    Abstract:

    Considerable uncertainty exists in the inventory of Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) emissions from uncontrolled combustion sources such as “backyard” burning of domestic waste. The contribution from these sources to the worldwide PCDD/F balance may be significant, but few quantitative sampling programs have yet assessed th

Christopher C. Lutes - One of the best experts on this subject based on the ideXlab platform.

  • emissions of pcdd f from uncontrolled domestic waste burning
    Chemosphere, 2001
    Co-Authors: Brian K Gullett, Paul M. Lemieux, Christopher C. Lutes, Chris K. Winterrowd, Dwain Winters
    Abstract:

    Abstract Emissions of Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) result from inefficiencies of combustion processes, most typically waste combustion. Uncontrolled combustion, such as occurs during so-called “backyard burning” of domestic waste, may therefore produce optimal conditions for formation and emission of PCDD/F. However, few assessments of PCDD/F emissions are available from these sources. This work describes the first known comprehensive assessment of PCDD/F emissions from uncontrolled, domestic waste burning. Emissions were copious, but highly variable, ranging over several orders of magnitude. The potential for emissions appears to be related primarily to combustion parameters and concentrations of various gas-phase species, the latter which may be affected by changes in waste composition, waste orientation, and/or combustion conditions.

  • Emissions of PCDD/F from uncontrolled, domestic waste burning
    Chemosphere, 2001
    Co-Authors: Brian K Gullett, Paul M. Lemieux, Christopher C. Lutes, Chris K. Winterrowd, Dwain Winters
    Abstract:

    Abstract Emissions of Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) result from inefficiencies of combustion processes, most typically waste combustion. Uncontrolled combustion, such as occurs during so-called “backyard burning” of domestic waste, may therefore produce optimal conditions for formation and emission of PCDD/F. However, few assessments of PCDD/F emissions are available from these sources. This work describes the first known comprehensive assessment of PCDD/F emissions from uncontrolled, domestic waste burning. Emissions were copious, but highly variable, ranging over several orders of magnitude. The potential for emissions appears to be related primarily to combustion parameters and concentrations of various gas-phase species, the latter which may be affected by changes in waste composition, waste orientation, and/or combustion conditions.

  • PCDD/F emissions from uncontrolled, domestic waste burning. Presented at Dioxin ’00
    2000
    Co-Authors: Brian K Gullett, Paul M. Lemieux, Christopher C. Lutes, Chris K. Winterrowd, Dwain L
    Abstract:

    Considerable uncertainty exists in the inventory of Polychlorinated Dibenzodioxin and dibenzofuran (PCDD/F) emissions from uncontrolled combustion sources such as “backyard” burning of domestic waste. The contribution from these sources to the worldwide PCDD/F balance may be significant, but few quantitative sampling programs have yet assessed th