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  • 1.
    Aurell, Johanna
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Haglund, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Effects of sulfur on PCDD/F formation under stable and transient combustion conditions during MSW incineration2009Ingår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 76, nr 6, s. 767-773Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    SO2 levels in the flue gas from a laboratory-scale fluidized bed reactor combusting artificial municipal solid waste (MSW) were varied (resulting in four different SO2:HCl ratios 0, 0.2, 0.7 and 2.7 (by mass)) to study the effects of sulfur on the formation of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzothiophenes (PCDTs). Sampling was performed simultaneously at three fixed points in the post-combustion zone with temperatures of 400, 300 and 200 °C, under normal combustion conditions and both during and after transient combustion conditions. The findings indicate that sulfur has a greater inhibitory effect on PCDF formation than on PCDD formation and that the PCDD/PCDF ratio in the flue gas depends on both the SO2:HCl ratio in the flue gas and memory effects arising from transient combustion conditions. The results also indicate that the relative importance of different pathways shifts in the post-combustion zone; condensation products increasing with reductions in temperature and increases in residence time. However, these changes appear to depend on the SO2:HCl ratio in the flue gas and combustion conditions. Sulfur seems to inhibit the chlorination of PCDFs. A tendency for increased SO2 levels in the flue gas to increase levels of PCDTs was also detected, but the increases were much less significant than the reductions in PCDF levels.

  • 2.
    Aurell, Johanna
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Effects of transient combustion conditions on the formation of polychlorinated dibenzo-p-dioxins, dibenzofurans, and benzenes, and polycyclic aromatic hydrocarbons during municipal solid waste incineration2009Ingår i: Environmental Engineering Science, ISSN 1092-8758, E-ISSN 1557-9018, Vol. 26, nr 3, s. 509-520Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study investigated the effects of transient combustion conditions on formation of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) along the postcombustion zone. Polychlorinated benzenes (PCBz) and polycyclic aromatic hydrocarbons (PAH) were also studied. The study was conducted in a laboratory fluidized-bed reactor fed with an artificial municipal solid waste (MSW) under controllable but realistic combustion conditions. PCDD/Fs, PCBz, and PAHs were monitored under normal, transient, and posttransient combustion conditions and simultaneously sampled at three different sampling points/temperatures (400°C, 300°C, and 200°C). Substantially higher PCDD/F, PCBz, and PAH concentrations were found during transient combustion than during normal combustion. Elevated concentrations were found to decrease with time. PCDD/F concentrations were similar at all points during normal and transient combustion conditions, but were found in higher concentrations at 200°C than 400°C under the posttransient combustion periods. Higher concentrations of the sum PAH and PCBz were also found at 200°C than 400°C in the posttransient combustion periods. Transient combustion conditions induced changes in both PCDD/F homologue profile and PCDD/F congener patterns compared to normal combustion. PCDD/PCDF ratios indicated an increase of the de novo synthesis during transient combustion conditions. Although, the PCDD/F congeners found to be most strongly affected by the transient combustion conditions indicated different reactions pathways active for formation of PCDF and PCDD, de novo synthesis and precursors, respectively. The most strongly affected PCDD/F congeners of transient combustion were identified and are presented.

  • 3.
    Aurell, Johanna
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Jansson, Stina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Effects of quench time profiles on PCDD/F formation in the postcombustion zone during municipal solid waste incineration2009Ingår i: Environmental Engineering Science, ISSN 1092-8758, E-ISSN 1557-9018, Vol. 26, nr 3, s. 541-550Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Effects of postcombustion zone temperatures and flue gas residence times on monochlorinated to octachlorinated dibenzo-p-dioxins and -furans (PCDD/F) in a laboratory-scale reactor combusting municipal solid waste were investigated. Four different quench time profiles were investigated, falling from 400°C to 200°C, 300°C to 100°C, 450°C to 200°C and 460°C to 260°C, with corresponding residence times of 1.4 to 4.4sec, 1.4 to 5.4sec, 1.3 to 4.3sec, and 1.3 to 4.0sec, respectively. Flue gas samples were collected simultaneously at three fixed sampling points, with an additional sampling of flue gas entering the postcombustion zone (640°C). The quench time profiles resulted in different total PCDD/F yields, as well as differences in homologue profiles and congener patterns. Thus, the formation pathways seem to be dependent on sufficient residence time within a specific temperature region. Formation of PCDD/F was shown to be rapid and mainly located to the 640°C to 400°C temperature region, with non-detectable levels at 640°C and concentrations at 400°C that did not increase or decrease significantly downstream. Furthermore, a prolonged residence time at and above 450°C/ 460°C showed low yields even downstream the postcombustion zone compared to the 400°C to 200°C and 300°C to 100°C profiles. The 460°C to 260°C profile resulted in increased abundance at the last two sampling points of PCDD congeners known to correlate with 2,4,6-trichlorophenols, suggesting that chlorophenol condensation reactions were promoted by this quench time profile.

  • 4.
    Aurell, Johanna
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Jansson, Stina
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Formation of Dioxins in a Modified Laboratory-Scale Fluidize-Bed Reactor During a Long-Term MSW Combustion Experiment2006Ingår i: Organohalogen Compounds, Vol. 68, s. 1205-8Artikel i tidskrift (Refereegranskat)
  • 5.
    Aurell, Johanna
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Effects of varying combustion conditions on PCDD/F emissions and formation during MSW incineration2009Ingår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 75, nr 5, s. 667-673Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Process, combustion and fuel parameters were varied to elucidate factors that substantially affect the formation and emissions of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) arising from municipal solid waste (MSW) incineration. The combustion conditions were varied by changing the: freeboard temperatures; quench time in the post-combustion zone; fuel load; chlorine and copper levels in the fuel; and the water, sulfur dioxide, carbon monoxide and oxygen levels in the combustion gases. The study was performed using a 5 kW laboratory-scale fluidized-bed reactor and PCDD/Fs were sampled at a point at 300 °C in the post-combustion zone. The results showed that increasing the SO2 level (from 0 to 130 ppm) substantially reduced the PCDD/F emissions, by up to 60%. In contrast, increasing the CO levels (due to transient combustion conditions), raising the Cl level (from 0.7% to 1.7%) and reducing the freeboard temperature (from 800 °C to 660 °C) all substantially increased the emission levels (more than 3-fold). Changes in PCDD/F profiles associated with increases in Cl, SO2 or CO levels and increasing the freeboard temperature (from 800 °C to 950 °C) indicate that the PCDFs were mainly formed by chlorination. In addition, increasing the Cl level increased the chlorination activity in the formation of PCDDs. Increasing the SO2 level appeared to be less effective in reducing the amount of PCDDs formed via the precursor pathway. While increased CO levels induced PCDD formation via the precursor pathway, although this was found to depend on the O2 level in the flue gas.

  • 6. Broz, J
    et al.
    Grabic, R
    Kilian, J
    Lojkasek, M
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Ocelka, T
    Pekarek, V
    Pribyl, J
    Tydlitat, V
    Vyska, J
    The effect of oils on PAH, PCDD, PCDF, and PCB emissions from a spark engine fueled with leaded gasoline2000Ingår i: Chemosphere, Vol. 41, nr 12, s. 1905-11Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The effect of synthetic and mineral oils on the formation of polyaromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) in emissions from a spark ignition engine was studied on a Skoda Favorit engine fueled with leaded gasoline. The test cycle simulated urban traffic conditions on a chassis dynamometer, in accordance with the ECC 83.00 test. The data for selected PAHs as well as PCDDs, PCDFs, and PCBs congener profiles are presented. PCDD/Fs emissions for an unused oil and the oil after 10000-km operation varied from 300 to 2000 fmol/m3, PCBs emissions from 75 to 178 pmol/m3, and PAHs emissions from 150 to 420 g/m3. The content of PCBs in oils varied from 2 to 920 mg/kg.

  • 7.
    Börjeson, L
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Löfvenius, G
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Hjelt, Maria
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Johansson, S
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Characterization of automotive shredder residues from two shredding facilities with different refining processes in Sweden2000Ingår i: Waste Management & Research, Vol. 18, nr 4, s. 358-66Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Strict legislation imposing producer responsibility on car manufacturers, introduced in 1998 in Sweden, has prompted a search for new alternatives for recycling organic materials In end-of-life vehicles (ELVs), i.e. the automotive shredder residue (ASR). The recovery of materials from ELVs must increase from the present 70 to 75%, to 95% by 2015. The aim of this study was to characterize material other than ferrous components, i.e. the (automotive) shredder residue [(A)SR] and the non-ferrous (NF), material in order to investigate its suitability for energy recovery. The results show that the good heat value of the material gives it potential, but high levels of metals and chlorinated compounds may cause problems. Levels of elements, metals and polychlorinated dibenzodioxins/furans (PCDD/F), polychlorinated biphenyls (PCB) and polychlorinated benzenes (PCBz) in the ASR were also analysed, and the results are described and discussed.

  • 8. Cieplik, Mariusz K
    et al.
    Carbonell, Jose Pastor
    Muñoz, Christina
    Baker, Sarah
    Krüger, Sophie
    Liljelind, Per
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Louw, Robert
    On Dioxin Formation in Iron Ore Sintering2003Ingår i: Environmental Science & Technology, Vol. 37, nr 15, s. 3323-31Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Iron ore sintering is an important source of "dioxins", polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). This paper reports on attempts to identify materials, conditions, and mechanisms responsible for PCDD/F formation (i) by investigating salient properties of ores (viz., with respect to oxidation, condensation, and chlorination of model organics) and (ii) by mimicking the industrial process on a microscale with real-life materials. Principles of Design of Experiments (DOE) are employed. The reactivities of iron ores differ greatly. Limonite/goethite "soft" ore is a very active oxidation catalyst (e.g., for benzene and phenol), a property that may be useful in cleaning up crude sintering process offgases, whereas hematite/magnetite "hard" ore is not. The latter, however strongly promotes condensation of phenol to dibenzofuran. A newly built lab-microscale sintering facility could satisfactorily imitate the large-scale process, in part or as a whole. Results obtained with realistic feed mixtures point at dioxin formation in the sinter bed at levels significant enough to explain a major part of the outputs observed in the real-life process. With ~8 ppm (wt) of chloride added as NaCl, the PCDD/F output doubled, but with the same proportion of chlorine administered as C2Cl4, the dioxin output was over 2 orders of magnitude larger. The use of process reverts, etc. containing chlorinated organics should therefore be avoided. PCDD/F congener patterns are also reported and compared with those observed in practice.

  • 9. Cieplik, M.K.
    et al.
    De Jong, V.
    Bozovic, J.
    Liljelind, Per
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Louw, R.
    Formation of dioxins from combustion micropollutants over MSWI fly ash.2006Ingår i: Environmental Science and Technology, ISSN 0013-936X, Vol. 40, nr 4, s. 1263-9Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Formation of polychlorinated dibenzofurans and dibenzo-p-dioxins (PCDD/Fs) from a model mixture of products of incomplete combustion (PICs) representative of municipal solid waste incineration (MSWI) flue gases, over a fixed bed of MSWI fly ash has been investigated. For comparison, a single model compound (chlorobenzene) was also briefly studied. A newly developed lab-scale system enabled the application of (very) low and stable concentrations of organic substances--of 10(-6) M or less-to approach realistic conditions. Samples taken at several time intervals allowed the observation of changes in rates and patterns due to depletion of the carbon in fly ash. The model flue gas continuously produced PCDDs and PCDFs after the de novo reaction had ceased to occur. Dioxin output levels are comparable to those of "old" MSW incinerators. Replacing the PIC trace constituent phenol by its fully 13C-labeled analogue led to, e.g., PCDD with one labeled ring as prominent product, meaning that the formation is about first order in phenol, contrary to earlier assumptions. The meaning of the results for the formation of dioxins in the MSWI boiler is discussed.

  • 10.
    Duong Phan, Ngoc Chau
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Weidemann, Eva
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Lundin, Lisa
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Jansson, Stina
    Swedish University of Agricultural Sciences.
    Accurate sampling of PCDD/F in high temperature flue-gas using cooled sampling probes2012Ingår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 88, nr 7, s. 832-836Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In a laboratory-scale combustion reactor, flue-gas samples were collected at two temperatures in the post-combustion zone, 700 °C and 400 °C, using two different water-cooled sampling probes. The probes were the cooled probe described in the European Standard method EN-1948:1, referred to as the original probe, and a modified probe that contained a salt/ice mixture to assist the cooling, referred to as the sub-zero probe. To determine the efficiency of the cooling probes, internal temperature measurements were recorded at 5 cm intervals inside the probes. Flue-gas samples were analyzed for polychlorinated dibenzo-p-dioxin and dibenzofurans (PCDD/Fs). Samples collected at 700 °C using the original cooling probe showed higher concentrations of PCDD/Fs compared to samples collected using the sub-zero probe. No significant differences were observed between samples collected at 400 °C. The results indicated that artifact formation of PCDD/Fs readily occurs during flue-gas sampling at high temperatures if the cooling within the probe is insufficient, as found for the original probe at 700 °C. It was also shown that this problem could be alleviated by using probes with an enhanced cooling capacity, such as the sub-zero probe.

    Although this may not affect samples collected for regulatory purposes in exit gases, it is of great importance for research conducted in the high-temperature region of the post-combustion zone. 

  • 11. Gönczi, M
    et al.
    Gunnarsson, M
    Hedman, B
    Johansson, N
    Näslund, M
    Marklund, Stellan
    Umeå universitet.
    Emissions of PCDD/F and PCB from uncontrolled combustion of domestic waste in Sweden2005Ingår i: Organohalogen Compounds, s. 2033-6Artikel i tidskrift (Refereegranskat)
  • 12.
    Hedman, Björn
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Burvall, Jan
    Nilsson, Calle
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Emissions from small-scale energy production using co-combustion of biofuel and the dry fraction of household waste2005Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 25, nr 3, s. 311-321Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In sparsely populated rural areas, recycling of household waste might not always be the most environmentally advantageous solution due to the total amount of transport involved. In this study, an alternative approach to recycling has been tested using efficient small-scale biofuel boilers for co-combustion of biofuel and high-energy waste. The dry combustible fraction of source-sorted household waste was mixed with the energy crop reed canary-grass (Phalaris Arundinacea L.), and combusted in both a 5-kW pilot scale reactor and a biofuel boiler with 140–180 kW output capacity, in the form of pellets and briquettes, respectively. The chlorine content of the waste fraction was 0.2%, most of which originated from plastics. The HCl emissions exceeded levels stipulated in new EU-directives, but levels of equal magnitude were also generated from combustion of the pure biofuel. Addition of waste to the biofuel did not give any apparent increase in emissions of organic compounds. Dioxin levels were close to stipulated limits. With further refinement of combustion equipment, small-scale co-combustion systems have the potential to comply with emission regulations.

  • 13.
    Hedman, Björn
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Burvall, Jan
    Nilsson, Calle
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    PCDD/F in source-sorted waste fractions and emissions from their co-combustion with reed canary-grass2007Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 27, nr 11, s. 1580-1592Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The dry combustible fraction of source-sorted household waste, including material that would otherwise be recycled, was mixed with the energy crop reed canary-grass (Phalaris arundinacea L.), and combusted as briquettes in 150 and 600 kW biofuel-boilers without advanced cleaning systems. The source-sorted waste was further sorted and characterized according to its material and chemical contents. The bulk of the waste’s chlorine content came from the non-package plastic fraction, whereas 90–95% of ∑PCDD/F (74–90% of WHO-TEQ) originated from the textile fraction. The sources of the dioxins in the waste fractions are discussed. The balance of dioxin levels was negative, i.e., the amounts of dioxins output in the flue gas were lower than those input in the fuel, except when there were operational disturbances in the combustion. In one of the combustion trials the total levels of dioxins in the flue-gas and ashes were also lower than the input levels. The use of additional cleaning equipment will be needed to ensure that emissions of dioxins and hydrochloric acid will be below legal limits.

  • 14.
    Hedman, Björn
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Näslund, Morgan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Emission of PCDD/F, PCB, and HCB from combustion of firewood and pellets in residential stoves and boilers2006Ingår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 40, nr 16, s. 4968-4975Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To assess potential emissions of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and hexachlorobenzene (HCB) from residential combustion of biofuels, experiments were performed in which various types of pellets and firewood were combusted in four types of stoves and boilers, with both full and reduced rates of air supply. Intermittent combustion of wood pellets resulted in emissions of 11 ng-(WHO-TEQ)/kg combusted fuel (dry weight). A modern, environmentally certified boiler yielded somewhat lower emissions of PCCD/F and PCB than a wood stove. Both gave <0.1 ng(WHO-TEQ)/m3n (1.3-6.5 ng(WHO-TEQ)/kg) and considerably lower emissions than an old boiler (7.0-13 ng(WHO-TEQ)/kg). No positive effect on emissions could be observed in full air combustion (simulating the use of a heat storage tank) compared to combustion with reduced air. Two of the wood combustion experiments included paper and plastic waste fuels. Chlorine-containing plastic waste gave rise to high emissions: ca. 310 ng(WHO-TEQ)/ kg over the whole combustion cycle. The homologue profiles of PCDD/Fs show characteristic differences between ashes and flue gas from combustions with different levels of air supply. These differences do not, however, seem to have any correlation to the relative amount of toxic congeners.

  • 15.
    Hedman, Björn
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Näslund, Morgan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Nilsson, Calle
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Emissions of polychlorinated dibenzodioxins and dibenzofurans and polychlorinated biphenyls from uncontrolled burning of garden and domestic waste (backyard burning)2005Ingår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 39, nr 22, s. 8790-8796Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To assess emissions of dioxins (chlorinated dibenzodioxins and dibenzofurans) and PCB from uncontrolled domestic combustion of waste ("backyard burning"),test combustions in barrels and open fires were monitored. The waste fuels used were garden waste, paper, paper and plastic packaging, refuse-derived fuel (RDF), PVC, and electronic scrap. Combustions including PVC and electronic scrap emitted several orders of magnitude more dioxins than the other waste fuels. Emissions from the other fuels had considerable variations, but the levels were difficult to relate to waste composition. Emission factors of PCDD/F and PCB from the backyard burning ranged from 2.2 to 13 000 ng (WHO-TEQ)/kg. The levels found in ash usually were less than 5% of the total. For assessment of total emissions of dioxins and PCB from backyard burning of low and moderately contaminated wastes, an emission factor range of 4-72 ng (WHO-TEQ)/kg is suggested. These figures imply that combusting waste in the backyard could contribute substantially to total emissions, even if the amounts of fuel involved are equivalent to just a few tenths of a percent of the amounts combusted in municipal waste incinerators.

  • 16.
    Jansson, Stina
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Antti, Henrik
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Correlations of PCDD/F isomer distribution patterns from MSW combustion with physicochemical variables and chlorine substitution descriptorsManuskript (preprint) (Övrig (populärvetenskap, debatt, mm))
  • 17.
    Jansson, Stina
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Antti, Henrik
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Multivariate Relationships between Molecular Descriptors and Isomer Distribution Patterns of PCDD/Fs Formed during MSW Combustion2009Ingår i: Environmental Science & Technology, Vol. 43, nr 18, s. 7032-8Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The isomer distribution patterns of mono- to hepta-chlorinated dibenzo-p-dioxins (PC1−7DD) and dibenzofurans (PC1−7DF) in postcombustion zone flue gas during incineration of an artificial municipal solid waste in a laboratory-scale fluidized-bed reactor were evaluated. Bidirectional orthogonal projections to latent structures (O2PLS) was used to correlate a set of physicochemical properties and chlorine substitution descriptors with the objective to identify parameters correlated with postcombustion zone PCDD and PCDF formation. The most influential variable for the distribution of PCDD congeners was chlorine substitution in positions 1 and 3 (Cl1 + 3), and overall the chlorine substitution descriptors exerted a larger impact on PCDDs than on PCDFs. For the PCDF, chlorination of the 9-position was the most influential X-variable. Distinct clustering was observed and was most pronounced for PCDFs, dividing most of the homologues into two or three subgroups of congeners. These subgroups seemed to correspond to the probability of formation by chlorophenol condensation. The sterically crowded dibenzofuran bay-sites (1- and 9-positions) were found to negatively influence PCDF formation, with chlorination of the 9-position having the greatest impact. Since PCDD/F toxicity is related to the lateral positions, elucidating the factors governing chlorination may be of great importance for detoxification of incineration byproducts.

  • 18.
    Jansson, Stina
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Aurell, Johanna
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Formation of Non-to Octachlorinated PCDD/F During MSW Combustion in a Laboratory-Scale Fluidized-Bed Reactor2006Ingår i: Organohalogen Compounds, Vol. 68, s. 165-8Artikel i tidskrift (Refereegranskat)
  • 19.
    Jansson, Stina
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Formation and chlorination of polychlorinated naphthalenes (PCNs) in the post-combustion zone during MSW combustion2008Ingår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 72, nr 8, s. 1138-1144Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Non- to octa-chlorinated naphthalenes (PCNs) were analyzed in flue gas samples collected simultaneously at three different temperatures (450 °C, 300 °C and 200 °C, respectively) in the post-combustion zone during waste combustion experiments using a laboratory-scale fluidized-bed reactor. PCN homologue profiles in all samples were dominated by the lower chlorinated homologues (mono- to triCN), with successive reductions in abundance with each additional degree of chlorination. The isomer distribution patterns reflected ortho-directionality behavior of the first chlorine substituent, and the β-positions, i.e. the 2,3,6,7-substitution sites, seemed to be favored for chlorination. Injection of naphthalene into the post-combustion zone resulted in increased PCN levels at 200 °C, demonstrating the occurrence of chlorination reactions in the post-combustion zone. However, the increases were restricted to the least-chlorinated homologue (monoCN), probably because there was insufficient residence time for further chlorination. In addition, an episode of poor combustion (manifested by high CO levels) was accompanied by extensive formation of 1,8-diCN, 1,2,3- and 1,2,8-triCN; congeners with substitution patterns that are not thermodynamically favorable. These are believed to be products of PAH breakdown reactions and/or chlorophenol condensation. Overall, PCN formation is likely to occur via more than one pathway, including chlorination of naphthalene that is already present, de novo synthesis from PAHs and, possibly, chlorophenol condensation.

  • 20.
    Jansson, Stina
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Post-combustion formation of PCDD, PCDF, PCBz, and PCPh in a laboratory-scale reactor: Influence of dibenzo-p-dioxin injection2009Ingår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 76, nr 6, s. 818-25Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Formation of polychlorinated dibenzo-p-dioxins (PCDD), dibenzofurans (PCDF), benzenes (PCBz), and phenols (PCPh) was studied during combustion of an artificial municipal solid waste (MSW) in a laboratory-scale fluidized-bed reactor with simultaneous collection of flue gas samples at three different temperatures in the post-combustion zone (450 degrees C, 300 degrees C, and 200 degrees C). PCDF, PCBz, and PCPh were predominantly formed at or above the first sampling point (450 degrees C) with a dominance of the lower chlorinated homologues. PCDDs, on the other hand, were dominated by the intermediately chlorinated homologues with concentrations peaking at 300 degrees C. The dominating PCPh congeners clearly displayed the ortho-para directionality, which is indicative of electrophilic aromatic substitution, as did the PCBz isomer distribution patterns to some extent. Comparison of the observed PCBz isomer distribution patterns to prior work may indicate coupling of aliphatic species in chlorobenzene formation. The PCDDs seemed to be largely influenced by chlorophenol condensation reactions and to some extent chlorination reactions, while the PCDFs displayed a chlorination-oriented pattern for the mono- to tri-chlorinated homologues and a PCPh condensation pattern for the higher chlorinated homologues. Injection of non-chlorinated dibenzo-p-dioxin at 650 degrees C resulted in increased formation of Tri-HxCDD and a decrease in the dibenzofuran levels. The affected PCDD and PCDF congeners were not products expected to form from chlorine substitution, but instead are well known chlorophenol condensation products.

  • 21.
    Liljelind, Per
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Söderström, Gunilla
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Hedman, Björn
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Karlsson, Stina
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Lundin, Lisa
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Method for Multiresidue Determination of Halogenated Aromatics and PAHs in Combustion-Related Samples2003Ingår i: Environmental Science & Technology, Vol. 37, nr 16, s. 3680-6Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Flue gas and fly ash samples have a complex composition. Thus, thorough extraction and selective cleanup prior to analysis are essential. This paper presents an evaluated method for determining halogenated dibenzo-p-dioxins (PXDD), halogenated dibenzofurans (PXDF), chlorinated biphenyls (PCB), chlorobenzenes (CBz), -phenols (CPh), dibenzo-p-dioxins (DD), dibenzofurans (DF), and polycyclic aromatic hydrocarbons (PAH) in a single sample. Since these combustion byproducts are ubiquitous, harmful environmental contaminants it is very important to obtain reliable assessments of them: especially specific PCDD/F and PCB congeners with Ah-receptor mediated toxicity. The reported method for this purpose includes techniques such as solid-phase extraction, Soxhlet-Dean-Stark extraction, cleanup using open liquid chromatographic columns, and finally GC/MS analysis/determination with quantification by the isotope dilution technique. The validation results presented here show good reproducibility for PXDD/F and PCB and are satisfactory for CPh, CBz, and PAH. An extraction efficiency test revealed that a nonpolar solvent did not completely extract a few analytes, i.e., diCPh and fluorene, which appear to require a more polar extraction agent. To pinpoint and minimize the loss of analytes, specific studies on reductions of their amounts during sample concentration were performed, showing that traditional rotary evaporation and nitrogen blow-down produce equally good results as a novel technique.

  • 22.
    Liljelind, Per
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Unsworth, John
    Maaskant, Onno
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Removal of dioxins and related aromatic hydrocarbons from flue gas streams by adsorption and catalytic destruction2001Ingår i: Chemosphere, Vol. 42, nr 5-7, s. 615-23Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The dioxin removing capacity of the shell dedioxin system (SDDS – a Ti/V oxidative type catalyst) has been tested using the Umeå lab-scale incinerator over the temperature range 100–230°C and at space velocities of 8000 and 40,000 h−1. Other analogous organic compounds, such as PCBs, PAHs, chlorobenzenes and chlorophenols have also been investigated. Results show a high degree of dioxin removal already at 100°C (82%), which occurs mainly by adsorption. When the temperature is raised a transition towards destruction is seen and at 150°C, gas hour space velocity (GHSV) 8000 and at 230°C, GHSV 40,000 virtually all removal is by destruction. High PCDD/F destruction efficiencies are reported (>99.9%, based on I-TEQ); the other dioxin-related species and PAHs are also removed and destroyed to a significant extent. The SDDS has proved to be an effective means of destroying organic compounds in the gas phase, particularly dioxins, at temperatures as low as 150°C.

  • 23.
    Lundin, Lisa
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Aurell, Johanna
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    The behavior of PCDD and PCDF during thermal treatment of waste incineration ash2011Ingår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 84, nr 3, s. 305-310Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) content of three fly ash samples with different elemental compositions from different municipal waste incinerators were analyzed before and after thermal treatment at 300°C or 500°C. Gas phase emissions during the treatments were also collected and analyzed. Substantial reductions in the total PCCD/F content of the ashes were observed after treatment at 500°C, seemingly due to degradation rather than dechlorination. Treatment at 300°C resulted in an increase in the PCDD/F content of the three ashes. Initial concentration of PCDD/F in the untreated ashes did not reflect the outcome of the treatment at the different temperatures. In addition, the composition of the ash was found to influence the rate of decomposition and formation of PCDD and PCDF during thermal treatment; the results showed that Cu, Fe, Ca and S play important roles in these processes.

  • 24.
    Lundin, Lisa
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Gullett, Brian
    Carroll, William F., Jr.
    Touati, Abderrahmane
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Fiedler, Heidelore
    The effect of developing nations' municipal waste composition on PCDD/PCDF emissions from open burning2013Ingår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 79, s. 433-441Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Open burning tests of municipal waste from two countries, Mexico and China, showed composition-related differences in emissions of polychlorinated dibenzodioxins and dibenzofurans (PCDDs/PCDFs). Twenty-six burn tests were conducted, comparing results from two laboratory combustion facilities. Waste was shredded to isolate composition-specific effects from those due to random waste orientation. Emissions ranged from 5 to 780 ng toxic equivalent/kg carbon burned (ng TEQ (kg C-b)(-1)) with an average of 140 ng TEQ (kg C-b)(-1) (stdev = 170). The waste from Mexico (17 ng TEQ (kg C-b)(-1)) had a statistically lower average emission factor than waste from China (240 ng TEQ (kg C-b)(-1). This difference was attributed primarily to waste composition differences, although one time-integrated combustion quality measure, Delta CO/Delta CO2, showed statistical significance between laboratories. However, waste composition differences were far more determinant than which laboratory conducted the tests, illustrated using both statistical techniques and comparison of cross-over samples (wastes tested at both facilities). Comparison of emissions from previous waste combustion tests in Sweden and the U.S.A, showed emission factors within the range of those determined for Mexico and China waste. For laboratory-scale combustion, existing emission factors and test methodologies are generally applicable to both developed and developing countries. Published by Elsevier Ltd.

  • 25.
    Lundin, Lisa
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Distribution of mono- to octa-chlorinated PCDD/F in fly ashes from a municipal solid waste incinerator2004Ingår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 42, nr 4, s. 1245-1250Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have estimated the concentration and distribution of the mono to octa-chlorinated congeners of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) in fly ashes at various sampling points in a large-scale municipal solid waste incinerator at Umeå, Sweden, as they cooled from 700 to 170 °C. Differences between the ashes were observed, the PCDD homologue profile was found to vary with temperature. The total amount of PCDD and PCDF increased as the temperature decreased in the postcombustion zone. The increase was due to both adsorption to the fly ash and formation of PCDD and PCDF. Mono- to trichlorinated PCDD predominated at high temperatures, whereas hepta- and octachlorinated PCDD predominated at temperatures below 400 °C. PCDF predominated over PCDD in the whole temperature range. However, the changes in homologue profile for PCDF were minor. The isomer distribution within the homologue groups was not changed as the temperature decreased in the postcombustion zone.

  • 26.
    Lundin, Lisa
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Distribution of mono to octa-chlorinated PCDD/Fs in fly ash from a municipal solid-waste incinerator.2008Ingår i: Environmental Science & Technology, ISSN 0013-936X, Vol. 42, nr 4, s. 1245-50Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have estimated the concentration and distribution of the mono to octa-chlorinated congeners of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) in fly ashes at various sampling points in a large-scale municipal solid waste incinerator at Umeå, Sweden, as they cooled from 700 to 170 degrees C. Differences between the ashes were observed, the PCDD homologue profile was found to vary with temperature. The total amount of PCDD and PCDF increased as the temperature decreased in the postcombustion zone. The increase was due to both adsorption to the fly ash and formation of PCDD and PCDF. Mono-to trichlorinated PCDD predominated at high temperatures, whereas hepta- and octachlorinated PCDD predominated at temperatures below 400 degrees C. PCDF predominated over PCDD in the whole temperature range. However,the changes in homologue profile for PCDFwere minor. The isomer distribution within the homologue groups was not changed asthetemperature decreased in the postcombustion zone.

  • 27.
    Lundin, Lisa
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Thermal Degradation of PCDD/F in MSW FLY ASH2006Ingår i: Organohalogen Compounds, Vol. 68, s. 147-150Artikel i tidskrift (Refereegranskat)
  • 28.
    Lundin, Lisa
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Thermal degradation of PCDD/F, PCB and HCB in municipal solid waste ash.2007Ingår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 67, nr 3, s. 474-481Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A thermal degradation procedure for reducing the concentrations of mono- to octa-chlorinated PCDD/Fs, PCBs and hexa-chlorobenzenes (HCB) in filter ash from incinerated municipal solid waste (MSW) is described. Thermal treatment of filter ash samples at 500 °C for 60 min in a closed system providing low oxygen conditions resulted in 97% and 99% reductions in the total and I-TEQ concentrations of PCDD/Fs, to 6.8 μg kg−1 ash and <0.05 μg I-TEQ kg−1 ash, respectively. Increasing the thermal treatment time to 480 min, at the same temperature, yielded 99% reductions in both total and I-TEQ concentrations of the mono- to octa-chlorinated PCDD/Fs. Similar effects were observed for HCB and PCBs. The data from this study indicate that PCDD/Fs and other toxic organic compounds in ash from incinerated MSW, can be effectively degraded by this procedure, which combines relatively low-temperatures, short treatment times, and low oxygen conditions.

  • 29. Lönnermark, Anders
    et al.
    Blomqvist, Per
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Emissions from simulated deep-seated fires in domestic waste2008Ingår i: Chemosphere, Vol. 70, nr 4, s. 626-39Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The emissions from deep-seated fires in domestic waste have been investigated. The gas phase yields of PAH, PCDD/F, PCB, HCB, particles, and metals associated to the particulate matter were analysed during a series of simulated deep-seated fires. The method of extinguishment was varied and in cases where water was used for extinguishment, the runoff water was analysed for PAH, PCDD/F, PCB, hexachlorobenzene, and metals. In total six tests were performed. In four of the tests, samples of the fire residue were analysed for PCDD/F, PCBs, and chlorobenzenes.

  • 30.
    Mikkola, Jyri-Pekka
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Jönsson, Leif
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Bio4Energy – The Swedish Quest for Sustainable Society:  FUEL, ENERGY and CHEMICALS2010Konferensbidrag (Övrigt vetenskapligt)
  • 31. Pekárek, V
    et al.
    Grabicb, R
    Marklund, S
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Punochá, M
    Ullrich, J
    Effects of oxygen on formation of PCB and PCDD/F on extracted fly ash in the presence of carbon and cupric salt2001Ingår i: Chemosphere, Vol. 43, nr 4-7, s. 777-82Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The effect of oxygen–nitrogen atmosphere (N2+10%O2,N2+1%O2 and 99.999% N2) on the formation of PCB, PCDD and PCDF by the de novo synthetic reactions in the system consisting of extracted fly ash (from municipal waste incinerators – MWI), activated carbon, CuCl2 · 2H2O and NaCl at 340°C was studied. The content of PCDD/F for systems with 10% O2,1%O2 and 99.999% N2 was decreasing and corresponded to 17304, 5544, and 1437 ng/sample. In all studied systems the isomer OCDD/F was prevailing. The content of PCBs in the same system was also decreasing from 1214 to 166 ng/g. Formation of nonortho PCB was relatively high compared to the system where only nitrogen was present. The possible mechanism of formation is outlined.

  • 32.
    Phan, Duong Ngoc Chau
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Boily, Jean-François
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Jansson, Stina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    A link between fly ash chemistry and the thermal formation of PCDDs, PCDFs, PCBs, and PCNs during waste incinerationManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    The relationship between the properties of fly ash generated during waste incineration and the thermal formation of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), and naphthalenes (PCNs) was investigated using a laboratory incinerator and two artificial wastes that were designed to reflect regional differences in municipal solid waste composition. Flue gas and fly ash samples were collected isokinetically via a sampling port in the post-combustion zone at a flue gas temperature of 300 °C. The mineralogical properties, morphology and sub-surface composition, surface composition and elemental oxidation states of the fly ash samples were determined. The flue gas samples were analyzed for Mo-OCDDs, Mo-OCDFs, Tri-DCBs, and Di-OCNs. Orthogonal Projections to Latent Structures (OPLS) modeling was used to study the relationship between the properties of the fly ash and the post-combustion formation of polychlorinated aromatics. The presence of high levels of ash-forming elements (i.e. Na, Mg, Fe, Ti, etc…) in the waste reduced the S content of the flue gas and thereby promoted the production of Cl2 via the Deacon process. Because this process is vital for the formation of polyaromatic species, wastes with depleted levels of fly ash-building elements should be favored to minimize the release of toxic PCDDs, PCDFs, PCBs, and PCNs during incineration.

  • 33.
    Phan, Duong Ngoc Chau
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Jansson, Stina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Effects of regional differences in waste composition on the thermal formation of polychlorinated aromatics during incineration2013Ingår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 93, nr 8, s. 1586-1592Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Two artificial wastes (A and B) whose contents reflect regional differences in municipal solid waste composition, were used to investigate the thermal formation of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), and naphthalenes (PCNs) during incineration. Flue gas samples were simultaneously collected at three ports in the post-combustion zone corresponding to flue gas temperatures of 400, 300, and 200 °C. The combustion of Waste B, which had a higher chlorine and metal content than Waste A, produced greater levels of highly-chlorinated homologues, as demonstrated by a higher degree of chlorination. The total concentrations of PCDDs, PCDFs, PCBs, and PCNs formed in the combustion of both wastes increased as temperature decreased along the convector. There were no significant differences in total concentrations between Waste A and Waste B combustion at specific temperatures, with exception of PCDFs at 400 °C. Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) modeling, used to evaluate the data for all compound groups, suggest that during flue gas quenching at temperatures of 400 °C low-chlorinated homologues are preferentially formed in the presence of copper, which is known to be a very active catalyst for this process. At 300 and 200 °C, the formation of highly-chlorinated homologues is favored.

  • 34. Redin, LA
    et al.
    Hjelt, Maria
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Co-combustion of shredder residues and municipal solid waste in a Swedish municipal solid waste incinerator2001Ingår i: WASTE MANAGEMENT & RESEARCH, ISSN 0734-242X, Vol. 19, nr 6, s. 518-25Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Incinerating automotive shredder residue (ASR) in order to increase the recovery from end of life vehicles (ELVs) is an attractive option when recycling this material. In this study, incineration combined with energy recovery, was investigated. The incineration experiments, where 20% shredder residue (SR) was burnt with conventional municipal solid waste (MSW), were conducted in a full-scale MSW horizontal grate incinerator. Measurements were made before, during and after the incineration. The results showed some minor increases in the emission levels of raw gases sampled after an electrostatic filter, but almost no significant differences when sampled after a wet scrubber. An increased level of 'non-toxic' metals was detected within the bottom ash. It was concluded that refined SR, in small quantities, is suitable to add to MSW.

  • 35.
    Söderström, Gunilla
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Formation of PBCDD and PBCDF during flue gas cooling2004Ingår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 38, nr 3, s. 825-830Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The presence of bromine and chlorine in combustion, particularly in waste combustion, results in the formation of PBCDD and PBCDF. Formation pathways of PCDD/F are not fully understood, although much is known about them, and they are currently being further investigated. PBCDD/F is likely to be formed in reactions similar to those leading to PCDD/F, but the processes involved have been less intensively studied. In this study a fuel with bromine and chlorine in equal molar amounts was combusted in a pilot-scale fluid bed reactor and the cooling flue gas was sampled at 800, 350, and 250 C. Analysis revealed that levels of PBCDD and PBCDF increased between all sampling ports. The chlorine/bromine ratio also increased with reductions in temperature and increases in residence time for both PBCDD and PBCDF. However, the formation of PBCDD and PBCDF seems to follow different routes with respect to the level and pattern of halogenation.

  • 36.
    Söderström, Gunilla
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    PBCDD and PBCDF from incineration of waste-containing brominated flame retardants2002Ingår i: Environmental science & technology, ISSN 0013-936X, Vol. 36, nr 9, s. 1959-64Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Brominated organic flame retardants comprise a large, heterogeneous group of compounds that are useful but also potentially damaging to the environment. In this investigation, three common brominated flame retardants were co-combusted with an artificial municipal solid waste in a pilot-scale fluidized bed incinerator. Combustion conditions ensured degradation of the flame retardants, but stable brominated organic compounds such as polybrominated dibenzo-p-dioxins and polybrominated dibenzofurans were formed in the cooling flue gases. The incineration of fuels that contain both chlorine and bromine leads to the formation of a complex mixture of polybrominated/ chlorinated dibenzo-p-dioxins and dibenzofurans. More bromination than chlorination was observed in these experiments, and the chlorination levels increased when bromine was added to the fuel. The most favored reactions led to the formation of dibromodichlorodibenzo-p-dioxin and dibromodichlorodibenzofuran. Theoretical calculations show that there is more Br[2] than Cl[2] in the flue gas when the two halogens are present at equimolar levels, because chlorine is mainly found in the form of HCl. This may explain the higher bromination level. BrCl is also present, which drives the chlorination observed when bromine is added.

  • 37.
    Weidemann, Eva
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Andersson, Patrik L.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Bidleman, Terry
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Boman, Christoffer
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för tillämpad fysik och elektronik.
    Carlin, Danielle J.
    Collina, Elena
    Cormier, Stephania A.
    Gouveia-Figueira, Sandra C.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Gullett, Brian K.
    Johansson, Christer
    Lucas, Donald
    Lundin, Lisa
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Lundstedt, Staffan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Nording, Malin L.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Ortuno, Nuria
    Sallam, Asmaa A.
    Schmidt, Florian M.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för tillämpad fysik och elektronik.
    Jansson, Stina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    14th congress of combustion by-products and their health effects-origin, fate, and health effects of combustion-related air pollutants in the coming era of bio-based energy sources2016Ingår i: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 23, nr 8, s. 8141-8159Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The 14th International Congress on Combustion By-Products and Their Health Effects was held in UmeAyen, Sweden from June 14th to 17th, 2015. The Congress, mainly sponsored by the National Institute of Environmental Health Sciences Superfund Research Program and the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning, focused on the "Origin, fate and health effects of combustion-related air pollutants in the coming era of bio-based energy sources". The international delegates included academic and government researchers, engineers, scientists, policymakers and representatives of industrial partners. The Congress provided a unique forum for the discussion of scientific advances in this research area since it addressed in combination the health-related issues and the environmental implications of combustion by-products. The scientific outcomes of the Congress included the consensus opinions that: (a) there is a correlation between human exposure to particulate matter and increased cardiac and respiratory morbidity and mortality; (b) because currently available data does not support the assessment of differences in health outcomes between biomass smoke and other particulates in outdoor air, the potential human health and environmental impacts of emerging air-pollution sources must be addressed. Assessment will require the development of new approaches to characterize combustion emissions through advanced sampling and analytical methods. The Congress also concluded the need for better and more sustainable e-waste management and improved policies, usage and disposal methods for materials containing flame retardants.

  • 38.
    Weidemann, Eva
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Bristav, Henrik
    Umeå Energi AB, Box 224, SE-901 05 Umeå, Sweden.
    Lundin, Lisa
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    In-filter PCDF and PCDD formation at low temperature during MSWI combustion2014Ingår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 102, s. 12-17Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This case study investigated PCDF and PCDD emissions from a 65 MW waste-to-energy plant to identify why an air pollution control system remodeling to accommodate increased production resulted in increased TEQ concentrations. Pre- and post-filter gases were collected simultaneously in four sample sets with varying filter temperatures and with/without activated carbon injection. Samples were analyzed to determine total PCDF and PCDD concentrations, as well as homologue profiles, and concentrations of individual congeners (some remained co-eluted). The total post filter PCDD concentrations where found to increase while the concentrations of PCDF and 2,3,7,8-substituted congeners declined. An investigation of the individual congener concentrations revealed that the increase of PCDD concentrations were due to a few congeners, suggesting a single formation route. The study also concludes that vital information about the formation could be obtained by not restricting the analysis to just the 2,3,7,8-substituted congeners. 

  • 39. Wikström, E
    et al.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Secondary Formation of Chlorinated Dibenzo-p-dioxins, Dibenzofurans, Biphenyls, Benzenes, and Phenols during MSW Combustion2000Ingår i: Environmental Science & Technology, Vol. 34, nr 4, s. 604-609Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this study was to investigate how the levels and homologue profiles of organic micropollutants (OMPs) were effected by the so-called secondary formation between 650 and 200 C. The combustion experiments were performed in a laboratory scale reactor fed with an artificial municipal solid waste fuel. The predominance of higher chlorinated OMP homologues after the secondary reaction shows that further chlorination reactions of OMPs formed at higher temperature reactions (>650 C) are more important in the lower temperature range than formation through the elements C, H, O, and Cl (de novo synthesis). Most of the dibenzofuran (DF), dibenzo-p-dioxin (DD), and the biphenyl (BP) are formed at temperatures higher than 650 C. Simultaneously flue gas sampling was taken in the convector section of the reactor at 650 and 200 C, respectively. The samples were analyzed for mono- to octachlorinated dibenzo-p-dioxins and dibenzofurans, tetra- to decachlorinated biphenyls, di- to hexachlorinated benzenes, and di- to pentachlorinated phenols. In addition to chlorinated OMPs, nonchlorinated DD, DF, and BP were analyzed.

  • 40.
    Wikström, E
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    The influence of level and chlorine source on the formation of mono- to octa-chlorinated dibenzo-p-dioxins, dibenzofurans and coplanar polychlorinated biphenyls during combustion of an artificial municipal waste2001Ingår i: Chemosphere, Vol. 43, nr 2, s. 227-34Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The formation of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and the three coplanar polychlorinated biphenyls (pPCBs) was studied during labscale fludized bed combustion of eight artificial municipal solid waste (MSW) fuel mixtures. The level of chlorine as well as the chlorine source varies within the different fuel mixtures. Four different chlorine sources were studied, viz, an inorgnaic (NaCl) and three organic sources, pure PVC plastic and two products (floor and cable) and the total chlorine level varies between 0.28% and 1.1%. The experiments were performed in a 5 kW laboratory scale fluidized bed reactor. A correlation between the total chlorine in the fuel and the formation of the hepta- and octa-chlorinated PCDD/F homologues was found. However, the most important variable for changes in the PCDDs/Fs and pPCBs formation was disturbance in the combustion condition and not the variation in chlorine content of the fuel. Furthermore, no differences in formation between the chlorine sources could be seen.

  • 41.
    Zhang, Tingting
    et al.
    POPs Research Centre, Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China.
    Fiedler, Heidelore
    UNEP/DTIE Chemicals Branch, 11-13, Chemin des Anémones, CH-1219 Châtelaine (GE), Switzerland.
    Yu, Gang
    POPs Research Centre, Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China.
    Ochoa, Gustavo Solorzano
    Instituto Nacional de Ecología – CENICA, 09340 México DF, Mexico.
    Carroll, William F
    American Chemistry Council, Chlorine Chemistry Division, 700 Second St., NE, Washington, DC 20002, USA.
    Gullett, Brian K
    US Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory (E343-04), Research Triangle Park, NC 27711, USA.
    Marklund, Stellan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Touati, Abderrahmane
    ARCADIS-US, Research Triangle Park, NC 27709, USA.
    Emissions of unintentional persistent organic pollutants from open burning of municipal solid waste from developing countries2011Ingår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 84, nr 7, s. 994-1001Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Open burning of waste is the most significant source of polychlorinated dibenzo-para-dioxins and dibenzofurans (PCDD/PCDF) in many national inventories prepared pursuant to the Stockholm Convention on Persistent Organic Pollutants. This is particularly true for developing countries. Emission factors for POPs such as PCDD/PCDF, dioxin-like polychlorinated biphenyls (dl-PCB) and penta- and hexachlorobenzenes (PeCBz/HCB) from open burning of municipal solid waste in China and Mexico are reported herein. Six different waste sources were studied varying from urban-industrial to semi-urban to rural. For PCDD/PCDF, the emission factors to air ranged from 3.0 to 650ngTEQkg(-1)waste and for dl-PCB from 0.092 to 54ngTEQkg(-1)waste. Emission factors for PeCBz (17-1200ngkg(-1)waste) and HCB (24-1300ngkg(-1)waste) spanned a wide but similar range. Within the datasets there is no indication of significant waste composition effect on emission factor with the exception of significantly higher Mexico rural samples.

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