The combustion of coal, and hydrocarbons generally, leads to the forma
tion of small but significant amounts of volatile organic compounds (V
OCs) and toxic organic micropollutants (TOMPs), as well as methane. Th
ese pollutants are generally considered to be formed in the combustion
zone, although it is known that some pollutants, such as dioxins, are
found in the cooled flue gases. It is shown here that the pollutants
undergo changes in concentration during the cooling process. These cha
nges are mapped for the major pollutants from a propane flame and coal
devolatilization products. (C) 1997 Elsevier Science Ltd.