Title: Effect of composting on sludge contaminated with heavy metals from three different tannery streams and their bioavailability to plants

Authors: EL Mahdi Ahmed Haroun, Azni Bin Idris, Syed Omar Syed Rustan

Addresses: Faculty of Engineering, Department of Chemical and Environmental Engineering, Universiti Putra Malaysia, 43400 UPM, Serdang, Malaysia. ' Faculty of Engineering, Department of Chemical and Environmental Engineering, Universiti Putra Malaysia, 43400 UPM, Serdang, Malaysia. ' Faculty of Agriculture, Department of Land Management, Universiti Putra Malaysia, 43400 UPM, Serdang, Malaysia

Abstract: This research was conducted to study the influence of composting on tannery sludge contaminated by Cr, Cd, Zn, Cu, and Ni. Composting of sludge streams was performed in three different piles for 60 days. The results showed that the total concentration of heavy metals was increased with composting, except in the TT-3 sample where the concentrations of Cd, Cu, and Ni did not increase. The composting led to a loss of weight, Composting rendered part of the metal insoluble. Ni was the most easily extracted by H₂O or CaCI₂ and was therefore the most weakly bound to the organic matrix; in contrast, Zn remained strongly bound.

Keywords: composting; carbon fractions; heavy metals; tannery sludge; sludge contamination; environmental pollution.

DOI: 10.1504/IJEE.2010.035459

International Journal of Environmental Engineering, 2010 Vol.2 No.4, pp.429- 446

Published online: 30 Sep 2010 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article