Size-resolved Emission Factors of Carbonaceous Particles from Domestic Coal Combustion in China

Abstract

China is one of the most important contributors to the global burden of carbonaceous aerosols, of which domestic coal combustion occupies a large fraction. Uncertainty in the emission factors (EFs) directly influences the accuracy of corresponding emission inventories. In the present study, based on domestic burning tests with a dilution sampling system, nine size-segregated particle classes emitted from the burning of three kinds of honeycomb coals (under flaming and smoldering burning conditions) and four kinds of chunk coals, including bituminous and lignite, were collected via a cascade impactor (FA-3). Organic and elemental carbon (OC and EC, respectively) were analyzed using the thermal-optical method. The EFs of particulate matter (PM), OC, and EC for nine size ranges were obtained. For honeycomb coals, the EFs of OC and EC in PM2.1 were 0.07 g·kg-1 and 0.002 g·kg-1, respectively, under flaming burning conditions and 0.10 g·kg-1 and 0.001 g·kg-1, respectively, under smoldering burning conditions. Carbonaceous particles exhibited higher EFs under flaming burning conditions. For chunk coals, the EFs of OC and EC in PM2.1 were 1.4 g·kg-1 and 0.02 g·kg-1, respectively, which are about one magnitude higher than those for honeycomb coal burning. Particulate matter and its associated carbonaceous components preferred to concentrate in fine particles. The EFs of carbonaceous components peaked at the size of ≤ 0.43 μm and 0.43-0.65 μm for honeycomb coal burning and chunk coal burning, respectively.