Mercury Speciation and Fine Particle Size Distribution on Combustion of Chinese Coals

摘要: Coal combustion is the dominant anthropogenic mercury emission source of world. Electrostatic precipitator (ESP) can remove almost all particulate (Hgp), and wet flue gas desulfurization (WFGD) retain a large part gaseous oxidized (Hg2+). Only small percentage elemental (Hg0) be abated by air pollution control devices (APCDs). Therefore, behavior across APCDs largely depends on speciation in exhausting from coal combustor. To better understand formation process three species, i.e. Hg0, Hg2+ Hgp, phase fine particles, bench-scale measurements for different types drop-tube furnace set-up, were carried out. It was observed that with limitation reaction kinetics, higher concentration will lead to lower proportion. The chlorine has opposite effect, not as significantly though. With increasing, proportion increases. Combusting finer powder results more Hg2+. Mineral composition particle size great impact formation. Al favor formation, while Fe benefit larger particles. coexistence Si strengthen coagulation process. This also improved feeding or powder. oxy-coal condition make both oxidation metal