The emission of polycyclic aromatic hydrocarbons from municipal solid waste incinerators during the combustion cycle

The emission of polycyclic aromatic hydrocarbons (PAHs) during start-up, burning, and burn-out were determined for four municipal solid waste MSW incinerators. During start-up conditions, PAH concentrations were shown to be high due to unstable combustion. A positive correlation was seen between PAH concentrations and the organic carbon content of the dust. This study was conducted to examine the emission behaviors of PAHs according to furnace type and to measure emissions during the combustion cycle. The organic carbon in the dust, as well as PAH emissions, during three combustion periods were determined for four MSW incinerators. PAHs were high during start-up because of incomplete combustion at low temperature. In the fluidized-bed incinerator, PAHs were high because combustion in the fluidized bed, was more unstable than in the step grate. A batch fluidized bed showed particularly higher concentrations compared to a continuous fluidized bed; owing to less stable combustion. Organic carbon in the dust was normally highest during start-up and lowest during burning. Continuous incinerators with longer operation periods showed higher emission rates during burning. This parameter for the batch-type fluidized bed increased during start-up and burn-out.