The aim of the work was to determine influence of time on organic matter content, nutrients concentrations as well as speciation of selected heavy metals (Cd, Pb, Ni, Cr, Cu and Zn) in sewage sludge stabilized in reed basins during 7-15 years. The analyzed sewage sludge was collected from reed basins from four municipal WWTPs located in Denmark serving from 9 000 to 40 000 pe in Vallo, Rudkøbing, Nakskov and Helsinge. Sewage sludge was collected along the vertical profile which was divided into 10 cm layers.Based on obtained results it was found that there were no significant changes in speciation of the heavy metals during long-term treatment in reed basins. The most important is that the analyzed heavy metals (except for Zn) were mostly bounded with the most stable - residual fraction. The most stable metals were: Pb and Cr where the share of residual fraction exceed 80% (concentration of residual fraction for Pb was average 11.75 mg/g d.s and for Cr 17.60 mg/g d.s.). The most mobile metal was Zn where the share of mobile fractions exceed 85% concentration of residual fraction was average 217.5 mg/g d.s.).
Authors
Additional information
- Category
- Aktywność konferencyjna
- Type
- publikacja w wydawnictwie zbiorowym recenzowanym (także w materiałach konferencyjnych)
- Language
- angielski
- Publication year
- 2008
