Emissions of organic compounds from biofuel combustion and influence of different control parameters using a laboratory scale incinerator

This study aimed at spanning the range of different wood combustion conditions by varying primarily load and airfeed in a controlled fashion, thereby investigating different combustion situations in this system. This was done using an experimental design. The aim was to see how these parameters effected organic emissions of PCDD/F, PCBz and PAH and to what extent their formation could be explained by means of the control parameters and other measured data. These data include inorganic combustion gases such as CO2 and NO and temperatures in the reactor. The results show that under the incineration conditions examined the organic emissions did vary but not in a way explainable by the parameters used here. Two samples were taken in parallel at different locations, before and after the convector region. The formation of PCDD/F and PCBz in the convector could be noted, suggesting similar mechanisms of secondary de novo formation for the two compound classes. This formation is significant, in some experiments up to 1000 % higher than at the furnace exit. Also when using a fuel with bark mixed into it the increase was ten fold.