Brominated aromatics from combustion
Öberg, T.
Proceedings from Workshop on Brominated Aromatic Flame Retardants, Skokloster, 24-26 oktober, 1989. Kemikalieinspektionen, 1990.

Abstract
I will review the results from investigations carried out during 1987 and 1988 (1-3).

All groups of halogenated aromatics, also brominated can be correlated to two basic factors in combustion processes: combustion efficiency and halogen input. The first factor determines the amount of organics present and the second the amount of reactive halogen.

In 1987 and 1988 several tests were completed at the SAKAB hazardous waste incinerator with different input levels of bromine. The results show that bromine load and combustion conditions clearly influences the production of brominated aromatics. Monobromotrichloro-p-dioxins and dibenzofurans were found in the flue gas samples.

These measurement results also show significantly higher yield of brominated compounds comparing the input of bromine with chlorine. The same results were found in our previous investigations of municipal waste combustion.

Recent measurements show that the concentrations of HBr in the flue gas from MSW incinerators are around 25 mg/m³ std dry gas at 10% CO₂, or 3.5% (w/w) relative to chlorine. This is twice the relative concentration in "normal" hazardous waste. A likely source for much of the bromine present in municipal waste is flame retardants in plastics.

Brominated aromatics can also be expected from other industrial processes contaminated with flame retardants and other brominated compounds, e.g. scrap metal re-melting.

The emissions of brominated and mixed halogenated aromatics, and limiting factors for the production, should therefore be evaluated carefully. The enormous analytical problems connected with mixed halogenated dioxins and dibenzofurans may be overcome using halogenated benzenes and phenols as indicator parameters (4-6).

References:

1. Öberg, T., Warman, K., Bergström, J. Chemoshere 16, 2451-2465 (1987).
2. Öberg, T., Bergström, J. Presented at AFRC International Symposium on Incineration Hazardous, Municipal, and Other Wastes, Palm Springs, November 2-4, 1987.
3. Öberg, T., Warman, K., Bergström, J. Chemosphere, in press.
4. Öberg, T., Bergström, J. Chemosphere 16, 1221-1230 (1987).
5. Öberg, T. Presented at the First Scandinavian Symposium on Chemometrics in Lappeenranta, October 6-8, 1988.
6. Öberg, T., Bergström, J. Chemosphere, in press.

Mass flow calc for Swedish waste incinerators
approx. 25 mg/m³ std dry gas at 10% CO₂
5000 m³/ton MSW
1.6 Mton incinerated/year
-->
approx. 200 ton Br₂/year