Characteristics of nanoparticles emitted from burning of biomass fuels

摘要

The characteristics of the particles of the smoke that is emitted from the burning of biomass fuels were experimentally investigated using a laboratory-scale tube furnace and different types of biomass fuels:rubber wood,whole wood pellets and rice husks.Emitted amounts of particles,particle-bound polycyclic aromatic hydrocarbons(PAHs)and water-soluble organic carbon(WSOC)are discussed relative to the size of the emitted particles,ranging to as small as nano-size(<70 nm),and to the rate of heating rate during combustion.differential thermal analysis(DTA)and thermogravimetric analysis(TG)techniques were used to examine the effect of heating rate and biomass type on combustion behaviors relative to the characteristics of particle emissions.In the present study,more than 30%of the smoke particles from the burning of biomass fuel had a mass that fell within a range of<100 nm.Particles smaller than 0.43μm contributed greatly to the total levels of toxic PAHs and WSOC.The properties of these particles were influenced by the fuel component,the combustion conditions,and the particle size.Although TG–DTA results indicated that the heating rate in a range of 10–20°C did not show a significant effect on the combustion properties,there was a slight increase in the decomposition temperature as heating rate was increased.The nano-size particles had the smallest fraction of particle mass and particle-bound PAHs,but nonetheless these particles registered the largest fraction of particle-bound WSOC.