| 21. |
- Öberg, Tomas, 1956-, et al.
(författare)
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Brominated aromatics from combustion
- 1987
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 16:10-12, s. 2451-2465
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Tidskriftsartikel (refereegranskat)abstract
- The production of brominated aromatics from combustion was shown to be influenced by the operating conditions. Brominated aromatics also showed high yields compared to their chlorinated analogues.
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| 22. |
- Öberg, Tomas, 1956-, et al.
(författare)
-
Bromine and waste incineration : an environmental risk?
- 1990
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Ingår i: Organohalogen Compounds. - 1026-4892. ; 2, s. 339-342
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Tidskriftsartikel (refereegranskat)abstract
- Process factors influencing the production of brominated aromatics in waste incinerators are bromine load and combustion quality. Emission measurements do not indicate unacceptable environmental risks from controlled combustion and advanced flue gas cleaning.
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| 23. |
- Öberg, Tomas, 1956-, et al.
(författare)
-
Catalytic effects by metal oxides on the formation and degradation of chlorinated aromatic compounds in fly ash.
- 2008
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Ingår i: Chemosphere. - Oxford : Pergamnon Press. - 0045-6535 .- 1879-1298. ; 71:6, s. 1135-43
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Tidskriftsartikel (refereegranskat)abstract
- Polychlorinated benzenes, dibenzo-p-dioxins (PCDD), and dibenzofurans (PCDF) may be formed below the combustion temperature in fly ash from municipal solid waste incinerators (MSWI). Copper catalyzes this formation, possibly by the Deacon reaction. Many other elements are also Deacon catalysts or promoters, and here we report results from a statistically designed experiment with 15 metal oxides added to fly ash and heated at 300 degrees C for 2h in an air atmosphere. A resolution IV fractional factorial design with four replicates was completed in 36 runs with the oxides of magnesium, yttrium, titanium, vanadium, niobium, chromium, molybdenum, tungsten, manganese, iron, cobalt, nickel, copper, zinc, and tin. All samples were analyzed for chlorinated benzenes and the results were evaluated by analysis of variance. The addition of copper significantly increased the amounts of the chlorinated benzenes, while cobalt, chromium and vanadium decreased the net formation. The oxides of zinc and iron seemed to have a slightly positive and negative effect respectively. The findings in this study seem to corroborate our previously reported results regarding the different catalytic effects of copper and chromium, and lack of a significant effect by nickel. Besides chromium, it also identifies cobalt and vanadium as potent catalysts for oxidative degradation of the chlorinated aromatic compounds found in MSWI fly ash.
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| 24. |
- Öberg, Tomas, 1956-
(författare)
-
Chemicals in Statistics - Method Development
- 2009
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Statistics on import, manufacture, and export of chemicals can be an important information source to follow up the results of environmental policy and management decisions. In this pilot study we evaluate the use of the official trade and manufacture statistics for the purpose of screening for bioaccumulating and persistent compounds of a particular environmental relevance. An impact index to measure these properties is applied to chemical groupings in the trade statistics. Furthermore, data from the trade statistics for selected chemicals is compared to corresponding data from the Swedish Products Register, at the Swedish Chemical Agency. The results show that the level of detail in the trade statistics does not permit estimation on the impact index using a compound specific index for environmental impact. In the trade statistics, a substantial number of chemicals with different properties are often grouped with the same identifier. However, this study shows that it is possible to use the same index to identify the groups containing the most problematic chemicals. The 100 chemicals identified to rank highest with regard to the potential environmental impact index belong to several groups, but 94 of these were halogenated. The two dominating groups in the trade statistics were halogenated aromatics and hydrochlorofluorocarbons (HCFC), with 25 and 20 members, respectively. A more detailed study of the trade statistics for these high-impact groups revealed substantial deviations between data from Statistics Sweden and Swedish Chemical Agency. Anomalies and an outlier were also observed and some misclassifications discovered. The self-reported statistics thus seems to need further validation to improve their usability for chemical policy purposes. Suggestions are made for further comparisons of databases, but tracing back to primary sources may also prove necessary to ensure relevance and good quality.
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| 25. |
- Öberg, Tomas, 1956-, et al.
(författare)
-
Chlorinated aromatics from metallurgical industries : Process factors influencing production and emissions
- 1989
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Ingår i: Chemosphere. - Oxford : Pergamon Press. - 0045-6535 .- 1879-1298. ; 19:1-6, s. 711-716
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Tidskriftsartikel (refereegranskat)abstract
- The emission and production of chlorinated aromatics from metallurgical industries, e g scrap-metal re-melting, show substantial variations due to a number of process factors. The data evaluated indicates clearly that the production of chlorinated aromatics is combustion controlled.
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| 26. |
- Öberg, Tomas, 1956-, et al.
(författare)
-
Chlorinated aromatics from the combustion of hazardous waste
- 1985
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 14:2, s. 215-221
-
Tidskriftsartikel (refereegranskat)abstract
- The production and emission of chlorinated aromatics from a hazardous waste incinerator were shown to be influenced by the operating conditions. The emissions of chlorinated benzenes, PCDD and PCDF show statistically significant correlations to the chlorine input. Different substance groups also correlate, and the results presented correspond well with a general formation mechanism of chlorophenols via chlorobenzenes as indicated by others.
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| 27. |
- Öberg, Tomas, 1956-, et al.
(författare)
-
Combustion test data from a Swedish hazardous waste incinerator
- 1986
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Ingår i: Chemosphere. - Oxford : Pergamon Press. - 0045-6535 .- 1879-1298. ; 15:9-12, s. 2045-2048
-
Tidskriftsartikel (refereegranskat)abstract
- Here we present results from our tests with PCB-incineration at the SAKAB hazardous waste incinerator in Norrtorp, Sweden. Combustion tests were made with PCB both as a fluid (Arochlor 1242) and as a contaminant of solid waste (Arochlor 1016 in capacitors). A general conclusion was that the incineration of considerable amounts of PCB did not effect the production of PCDD and PCDF in this combustion plant.
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| 28. |
- Öberg, Tomas, 1956-, et al.
(författare)
-
Different catalytic effects by copper and chromium on the formation and degradation of chlorinated aromatic compounds in fly ash.
- 2007
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Ingår i: Environmental Science and Technology. - Washington : American Chemical Society. - 0013-936X .- 1520-5851. ; 41:10, s. 3741-3746
-
Tidskriftsartikel (refereegranskat)abstract
- Fly ash from municipal solid waste incineration may catalytically enhance the formation and degradation of chlorinated aromatic compounds. The activities of three Deacon catalysts in this process were investigated in a statistically designed experiment. Chlorides of copper, chromium, and nickel were added to fly ash samples and the resulting samples heated at 300 degrees C for 2 h in an air atmosphere. The addition of copper increases the formation of all chlorinated aromatic compounds except the low chlorinated congeners of polychlorinated dibenzo-p-dioxins and dibenzofurans. The addition of chromium decreased the formation of most chlorinated aromatic compounds except the highest chlorinated species, where it was without effect. The addition of nickel did not show any significant effect. The outcome of the experiment can be interpreted as two competing processes: the chlorination of aromatic rings and the oxidation of carbon-carbon and carbon-oxygen bonds. The delicate balance between chlorination and oxidation could probably be further exploited to minimize both the emissions and the net production of chlorinated aromatic compounds from combustion.
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| 29. |
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| 30. |
- Öberg, Tomas, 1956-, et al.
(författare)
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Dioxins from Scandinavian waste combustion plants
- 1986
-
Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 15:9-12, s. 2041-2044
-
Tidskriftsartikel (refereegranskat)abstract
- A large quantity of emission data for PCDD and PCDF have been reported to date. Less information is available concerning the controlling parameters for the production of chlorinated aromatics from waste combustion. Here we report results and conclusions from investigations carried out in the Scandinavian countries to date.
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