The Impact of Combustion Efficiency on the Chemical Composition of Particle-Bound Organics from Residential Heating with Wood and Coal
PATRICK MARTENS, Hendryk Czech, Jürgen Orasche, Mika Ihalainen, Martin Sklorz, Olli Sippula, Ralf Zimmermann, Desert Research Institute
Abstract Number: 551
Working Group: Combustion
Abstract
Small-scale residential heating and cooking appliances fueled with coal are important sources of air pollution in Eastern Europe and China, and consequently fine particulate matter from coal burning is a large burden to public health in these areas. Even though coal has already been recognized as a big contributor to air pollution decades ago, information on the chemical composition of particle-bound organics, beyond some frequently targeted polycyclic aromatic hydrocarbons, alkanes and selected marker species that only make up a small fraction of the organic aerosol, is scarce.
To get further insight into the chemical composition of the unresolved complex mixture, emissions of fine particulate matter from a modern, residential wood stove were sampled on filters, subsequently analyzed with a thermal-optical carbona analyzer that was interfaced with a photo-ionization time-of-flight mass spectrometer and compared to emissions from burning spruce logs in the same stove. The thermal-optical carbon analyzer was used to parametrize the volatility of the organic aerosols using the Improve_A protocol, and the mass spectrometer is used to analyze the chemical composition of the evolving gas mixture.
The chemical nature of particle-bound organic compounds from residential coal burning indicated a tendency towards stronger graphitization with higher combustion quality. It is likely that cracking reactions in the flame were more pronounced at higher combustion quality and led to the stripping of functional moieties and substituents from semi-volatile and low-volatile aromatics, increasing the similarity to the chemical composition of high-quality wood combustion emissions. The change in the chemical nature may also trigger different toxic responses due to their different bioavailability and water solubility.