Agricultural biomass is considered a preferred renewable energy source in
Serbia because of its availability and suitability to limit the use of
fossil fuel resources and reduce greenhouse gas emissions. Therefore,
constant work has been done to develop technologies that enable its
utilization for energy purposes. As an example of these efforts, in the
Agricultural Corporation PKB, the soybean straw cigarette-type combustion
system has been applied for greenhouse heating for over a decade. However,
many volatile and semivolatile organic compounds are emitted directly into
the atmosphere or concentrated in ash particles during agricultural biomass
combustion. Since some of the emitted compounds, such as polycyclic aromatic
hydrocarbons (PAHs), are toxic, monitoring their concentrations in fly ash
is recommended. Literature data regarding PAHs content in agricultural
biomass ashes are insubstantial, especially in Serbia. For that purpose,
PAHs contents in the cyclone (CB) and stack (SB) fly ashes of soybean straw
were investigated and compared. In addition, the emission factors, toxicity,
carcinogenicity and benzo[a]pyrene equivalence concentrations were
determined and used to estimate the potential environmental impact of these
ashes. As a result, SB ash has been shown to have a higher potential
environmental risk than CB ash. Hence, an assessment of using soybean straw
as a feed fuel in a real cigarette-type combustion plant regarding PAHs
emission is given. These results provide important information for
optimizing combustion conditions and assisting the local entities in
managing air pollution and control policies in Serbia.