Ct. Li et al., PAH EMISSION FROM THE INCINERATION OF WASTE OILY SLUDGE AND PE PLASTIC MIXTURES, Science of the total environment, 170(3), 1995, pp. 171-183
A batch-type, controlled-air incinerator was used for the treatment of
oily sludge and polyethylene (PE) plastic mixtures. The concentration
and composition of 21 individual PAHs (polycyclic aromatic hydrocarbo
ns) in the raw wastes, flue gas (gas and particle phases) and ash were
determined. Stack flue-gas samples were collected by a PAH stack-samp
ling system. Twenty one individual PAHs were analyzed primarily by a g
as chromatograph and a gas chromatography/mass spectrometer. Due to in
complete combustion, PAH content in the feeding wastes have a strong i
nfluence on PAH emission in both stack flue gas and ash residue. With
the oily sludge in the feeding waste mixtures, the input mass of lower
molecular weight PAHs - Nap, AcPy, Acp, Flu, PA, Ant and FL - was con
tributed mainly by liquid diesel, while the input mass of higher molec
ular weight PAHs - Pyr, CYC, CHR, BbF, BkF, BeP, BaP, PER, IND, DBA, B
bC, BghiP and COR - was primarily contributed by the oily sludge. For
the distribution of individual PAH mean output mass, lower molecular w
eight PAHs - Nap, AcPy, Acp and Flu - have > 87% of their mass dischar
ged by the stack flue gas. However, the higher molecular weight PAHs -
Ant, FL, CHR, BbF, BeP, BaP, PER, IND, DBA, BbC, BghiP and COR - have
significant mass fractions (>18%) discharged by the ash residue. The
total-PAH output/input mass ratios were between 0.00103 and 0.00360 an
d averaged 0.00203. This result indicated that the depletion of PAH ma
ss in the combustion process was very significant The PAH content in t
he fuel during the combustion process is the control factor of PAH emi
ssion. The co-combustion of oily sludge with plastic is a potential me
thod of reducing the PAH emission and of saving the consumption of aux
iliary fuel.