Size Distribution Of Heavy Metals In Particles Emitted From Domestic Coal Burning And The Establishment Of Emission Inventory

Based on a dilution sampling system and domestic burning tests, the particles of different size fractions from three kinds of honeycomb coals and four kinds of raw coals burning were collected by cascade impactors (Andersen- II). The contents of V,Cr,Mn,Co, Ni,Cu,Zn,As,Cd,Sb and Pb were analyzed to get the distribution characteristics and emission factors of them in different particle size fractions. Honeycomb coals were burned under flaming and smoldering condition.Emission factors (EFs) for the eleven heavy metals in fine particulate matter (PM2.1)from raw coal and honeycomb coal burning were calculated, with their contents in raw coals of different provinces used. Then combined the EFs with the consumption amounts of residential coals, total emission amounts of heavy metals from residential coals burning in 2012 of China were calculated. Based on the information of population distribution, 1 km×1 km grid cell-based emission inventories were established. Results showed that:(1) Zn and Pb were the main heavy metal components in the particles from residential coals burning. Zn and Pb accounted for 45.9 - 62.7% of the total heavy metal from four kinds of raw coals burning, and accounted for 60.9 - 85.3% of the total heavy metal from three kinds of honeycomb coals flaming. Zn and Ni were the main components in the smoldering of honeycomb coals, accounting for 63.4 -68.4% of the total heavy metals.(2) PM2.1 were the main components in PM10 from row coals burning and honeycomb coals flaming, and they accounted for 50.8 - 58.5% of PM10. The coarse particles were main components of PM10,for honeycomb coal smoldering and PM2.1 accounted for only 14.1 - 26.9% of PM1O. Zn and Pb are the most important heavy metal components for row coals burning and honeycomb coals flaming. They mainly distributed in the size of 0.65 -1.1?m and ? 0.43?m. The 41.3% of Zn content and 45.4% of Pb content from row coal burning and the 56.0% of Zn content and 67.5% of Pb content from honeycomb coal flaming were in the two size ranges.The emission factors of heavy metals from honeycomb coal smoldering varied less in different particle sizes.(3) The total emissions of V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Sb and Pb in PM2.1 from residential coal burning in 2012 were 46.6?41.4?10.5?1.1?74.1?32.9?709.1?11.0?2.0?0.3 and 98.2t.Zn was the most important heavy metal element in fine particulate matters released from residential coals burning, accounting for 69.0% of the total heavy metals, followed by Pb and Ni, accounting for 9.6% and 7.2% of the total heavy metals respectively.(4) Hebei, Inner Mongolia, Henan, and Shandong held higher emission amounts, which totally accounted for 40.3% of the emission amounts of the whole country. Beijing, Tianjin, Hebei, Henan, Guizhou, Hunan and Inner Mongolia were the regions with higher emission intensities and emission amounts per capita.(5) The spatial distribution showed that the higher emissions per unit area of Zn?V?Cr and Cu mainly distributed in Baoding, Shijiazhuang, Hengshui, Tangshan,which are in Hebei province and most parts regions of Henan province; The higher emissions per unit area of Pb mainly distributed in Shandong province besides the aboved regions; The higher emissions per unit area of Mn,Co, Ni and Cd mainly distributed in Beijing, eastern Sichuan and Chongqing; For As and Sb, the higher emissions per unit area mainly distributed in Guizhou.