LAUSR

Abstract In order to grasp the suppression mechanisms of polycyclic aromatic hydrocarbons (PAHs) formation by coarser-sized bed material in the process of solid waste incineration. Medical waste incineration with silica bed materials under three particle sizes (160–180 μm, 180–250 μm and 250–320 μm) was carried out in a fluidized bed combustor (FBC). The distributions and contents of PAHs, monocyclic aromatic hydrocarbons (MAHs) and light hydrocarbons along the vertical direction (0.4, 0.7 and 1.0 m) were also measured. The results showed that the PAHs concentrations in flue gas had a positive correlation with the concentrations of MAHs and light hydrocarbon during medical waste incineration. The suppression of PAHs formation by the coarser-sized silica (250–320 μm) bed material was mainly attributed to the lower heat transfer rate between the bed material and medical wastes, which resulted in slower evolution rates of MAHs and light hydrocarbon, thus inhibiting the formation of MAHs, light hydrocarbon and PAHs.