Chemical composition and morphology of particles emitted from a wet flue gas desulfurization (WFGD) system

•Particles emitted from WFGD system are mainly carried from the SiO2 inlet gas flow.•The inlet particle characteristics and the L/G ratio affect the particle emissions.•Ca and S are the dominant elements in particles that are carried from slurry.•The particles emitted from the WFGD system were dominated by fine particles.•The mean diameter of the emitted particles were between 0.6 and 1.2 μm. The chemical composition and morphology of particles emitted from a WFGD system were analyzed. The inlet particle diameter, inlet particle concentration and liquid/gas ratio (L/G), were all found to affect particle emissions. Smaller diameter particles and higher inlet particle concentrations resulted in increases Si and total particle mass concentrations. The elemental mass concentrations of the emitted particles were mainly derived from inlet components, along with low levels of Ca, S, AL, Mg and other trace elements carried from slurry in the spray scrubber, with the Ca and S content of emitted particles predominantly being carried from the slurry. The particles emitted from WFGD were mainly fine particles, with up to 96% and 50% of particles being below 2.5μm and 1μm, respectively. Particles with a diameter below 0.5μm accounted for only 8.89%, 7.6% and 16.4% of particle emissions when the inlet particles sizes were 38.55μm 13.42μm and 6.16, respectively. The mean diameter of particles emitted from the WFGD system ranged between 0.6 and 1.2μm. These results confirm the particle removal ability of the WFGD system and improve our understanding of the chemical composition and morphology of particles emitted from WFGD systems, as well as their impact on the atmospheric environment.