| Based on a dilution sampling system and domestic burning tests, emission factors (EFs) for eleven heavy metals of V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Sb and Pb in PM2.5 from raw coal and honeycoal burning were calculated, using their contents in raw coals of different provinces. Then the total emission amounts of heavy metals from residential coals burning in 2012 were calculated and 30 km×30 km grid cell-based emission inventories were established. The results showed that the EFs of Pb, Zn, As and Cu were higher from honeycomb coal burning. They were 27.1, 16.8, 0.99 and 0.97 mg·kg-1, which were 56, 6, 10 and 2 times of those for raw coal, respectively. The total emissions of V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Sb and Pb in PM2.5 from residential coal burning in 2012 were 0.5, 30.1, 59.5, 1.1, 29.3, 20.0, 188.9, 64.9, 1.6, 3.4 and 176.7 t. Hunan, Hebei, Inner Mongolia, Henan, and Shandong held higher emission amounts, which were 12.4%, 12.3%, 10.4%, 9.9% and 9.3% of the total emissions of the whole country. Beijing, Henan, Shandong, Hunan, Jiangxi, Guizhou and Inner Mongolia were the regions with higher emission intensities and emission amounts per capita. The spatial distribution showed that the regions with higher annual emissions of Zn and Pb distributed widely, mainly in Inner Mongolia, Hebei, Beijing, Tianjin, Shandong, Henan, Gansu, Hunan and Jiangxi. The emission inventories for heavy metals in fine particles established here are important for regional air quality modeling and human health risk assessment. |
