CHLORINATED DIOXINS AND DIBENZOTHIOPHENES IN FLY-ASH SAMPLES FROM COMBUSTION OF FEAT, WOOD CHIPS, REFUSE DERIVED FUEL AND LIQUID PACKAGING BOARDS

Peat, wood chips, refuse derived fuel and liquid packaging board in di fferent combinations were burned at a temperature of at least 850 degr ees C. Fly ash samples from these combustions were analyzed for polych lorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzothiophe nes (PCDBTs) by high resolution GC/MS. The concentrations of tri- and tetrachloro-dibenzothiophenes and tri-, tetra- and pentachlorodioxins were highest when mixtures of wood chips and refuse derived fuel (RDF) were burned. The fly ash from the combustion of pure peat pellets did not contain any polychlorinated dibenzothiophenes. When wood chips an d RDF were burned the concentrations of chlorinated compounds in fly a sh were found to increase with increasing concentration of chlorine in the fuel.