Residential biomass combustion aerosols - influence of combustion conditions on physical and chemical particle characteristics

INTRODUCTION Combustion of biomass occurs on many scales from small residential fire places indoors to well controlled large boilers for energy production and biomass burning during deforestation. Particle emissions from such sources may affect both human health and global climate. It is well established that the particle emissions during less optimised combustion in small scale fire places and during deforestation are most often dominated by products of incomplete combustion, i.e. organic and elemental carbon (OC/EC). In contrast during optimised combustion in large boilers and modern domestic pellets combustion systems the aerosol can be dominated by ash compounds, especially KCl and K2SO4 formed via heterogeneous reactions in the gas-phase. However, surprisingly little research has focused on the variations in physical and chemical particle properties between different combustion technologies or when varying the combustion conditions within the same unit. The aim of this work was to study the physical and chemical properties of particles emitted during combustion of woody biomass pellets at different operation conditions.