Emission Characteristics of Particulate Matter from Rural Household Biofuel Combustion in China

Field measurements in rural households were conducted in three Chinese municipalities/provinces (Beijing, Chongqing, and Henan) to determine the emission characteristics of particulate matter from biofuel combustion. The selected biofuel types and stove types are representative of local rural areas. Particle number concentration, size distribution, and mass size distribution were determined. Both the particle number and mass of these emissions were dominated by submicrometer particles. The emission factor of PM2.5 from combustion is between 1.80 and 7.00 g/kg of biofuel (dry basis) and 0.84−2.40 g/MJ of delivered energy and is averaged to 4.21 g/kg of biofuel (dry basis) and 1.46 g/MJ delivered energy. In this study, it appears that particle emissions can be correlated with combustion conditions and stove configuration. Particle emissions are the highest during the high power phase. Unfortunately, the more thermally efficient stove has higher per kilogram fuel particulate matter (PM) emissions than the less thermally efficient stoves, that is, the increase in thermal efficiency cannot offset the increase in particle emissions.