Characterization of ultrafine particles from CHP Plants < 25 MWe

Key findings were: • The mass emissions from the WTE plants were very low due to the use of efficient bag filters and Electrostatic Precipitators (ESP) for emission control at these plants. • A significant enrichment of metals (e.g. Fe, Mn, Cu) in the PM0.1 and the PM1 fractions were found for particles from both WTE and BM plants. • The high number of particles emitted from the gas engines in the GF plants is most probably caused by the use of lubrication oil. • The FIB-SEM analysis of particles from the gas fired plants showed that the soot particles of a diameter of 150 nm – 1000 nm from these plants may be hollow as well as solid.