The effect of transient operations on the levels and congener profiles of PCBz, PCPh and PCDD/F in raw flue gases of MSWI plant

The concentrations and congener profiles of polychlorinated benzenes, phenols, dibenzo-p-dioxin and dibenzofurans, measured in raw flue gases of a real MSWI plant, are discussed in this paper. The data covers steady-state and transient operation conditions, including the memory effect period close to two shutdowns. The highest levels of concentrations of the pollutants were observed the first day after the shutdown with subsequent gradual decrease towards steady-state values. The conditions of the steady-state period prior to shutdown are decisive for the increase of start-up values, memory effect values and memory effect length. We found that the above-mentioned pollutants had a different length of the memory effect period. It can be concluded that under plant transient operation the formation of pollutants by the de novo synthesis is higher than under steady-state conditions.