Atmospheric trace element pollutants from coal combustion

In summary, analyses have been obtained for approximately 60 elements for sized flyash particles from two coal-fired steam plants. Evaluation of data from the elemental analyses, including the concentration dependence upon particle size, electron microscopy, ESCA, and mass spectrometry suggests a mechanism for formation of the submicron particles in some coal-fired plants. This mechanism involves bursting of larger particles during gas expansion and production of a very large number of very small particles which ultimately form particles in the 0.1 ..mu..m to 1.0 ..mu..m size range by coagulation. The condensation of volatilized material would then proceed concurrently with the bursting and coagulation process. The factors which determine the volatility of trace elements during coal combustion have been examined. While the organic affinities of individual trace elements in coal are likely to play a role, we have been unable to obtain clear verification of this point in initial studies