Formation of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) during the combustion of impregnated wood
T Salthammer, H Klipp, R-D Peek
Wood waste and industrial wood residues often contain various preservatives. The waste management for these residuals can be recycling, deposition or combustion. Among the three possibilities, combustion seems to be the most efficient way of disposal. To obtain detailed information about emissions of organic compounds with environmental impact, especially polychlorinated dibenzo-p-dioxins (PCDD) and furans (PCDF), different impregnated wood materials were incinerated in two furnaces after mixing with non-treated wood in a ratio of 1:4. The combustion process of residues containing organic or inorganic preservatives is influenced by the elementary composition of the preservative and the thermal and oxidative reaction paths in the flame. It was found that the concentrations of PCDD and PCDF in the exhaust gas can be kept low under good combustion conditions. However, a non-regular incineration process strongly supports increased emissions of PCDD and PCDF.