Laboratory Study on Composting of Soil with Combined Pollutants of Phenanthrene and Lead

Soil with combined pollutants of phenanthrene (phe) and lead (Pb) or with either of them were composted in three laboratory reactors to study the degradation of phe and the reduction of the solubility and bioavailability of Pb during composting. The change of the residual ratio of phe, the transformation of Pb, and the parameters of composting including pH and volatile solids (VS) were investigated. The results indicated that Compostings in all the three reactors could be processed without adjusting pH and VS. Above 50% of Pb was bound to the residual fraction and the content of phe could be decreased to 9.5% by composting in the reactor with the combined pollutants. Pb inhibited the biodegradation of phenanthrene to some extent and the effect of phe to the transformation of Pb was small during composting. Keywords-soil; lead; phenanthrene; combined pollution; composting