Evaluation of industrial wastes as active materials in permeable reactive barrier for acid mine drainage remediation

The aim of this work was to evaluate the use of agricultural and industrial waste materials as reactive agents into Permeable Reactive Barriers (PRB) for Acid Mine Drainage (AMD) remediation. Laboratory-scale columns containing Volcanic Scoria (VS) as porous fill material and approximately 18% w/w of industrial wastes used as reactive materials were used as PRB under up-flow continuous mode treating 1.9 L AMD d-1. Drinking water sludge (DWS) clearly enhanced AMD remediation because of chemical neutralization and biological sulphate reduction, which produced metals precipitation. The removal yields obtained when using DWS as reactive material ranged from 60 to 90%. Because of these results, the use of the DWS in PRBs would allow to simultaneously carry out the management of an industrial waste and the remediation of AMD through a low-cost and environmentally sustainable procedure.