Physicochemical characterization of the industrial tannery sludge

Abstract EN

It is very important that tannery wastes in the form of sludge are managed in an environmentally sound manner.

This study focused on the heavy metal characterization and the influence of changing the physico-chemical properties of the effluent tannery sludge after a sequence of compiand treatment of chemical treatment by Cement Kiln Dust (C.

K.

D) followed by anaerobic treatment by using up-flow anaerobic sludge blanket (UASB), bioavailability or chemical forms of Cr, Cu, Zn, Pb and Cd in tannery sludge.

The physical and chemical properties of the tannery sludge during treatment show the stability and maturity of end product.

Subsequent anaerobic treatment by using UASB was carried out at a division of the experiment into five distinct phases : Phase 1 (days 1-110) corresponds to the starting phase of the reactor.

Phase 2 (days 110-160) corresponds to a rapid hardening of the environmental conditions.

Phase 3 (days 160-210) was characterized, HRT of 14 hr by a return to the conditions of phase 1.

Total metal content in the final compost were much lower than the limit values of composts to be used as good soil fertilizer or in agriculture.

Furthermore, it was observed that the following metals : Cr, Cu, Co, Pb, Mn, Fe, Zn and Ni found in tannery effluent sludge were found to be below the tolerance levels and hence posed no danger to man and livestock.

That lead to the possibility to use the treated effluent of sludge after a combined system in soil fertilizer.