Removal of heavy metals from leachates using organic/inorganic permeable reactive barriers

ABSTRACT

In the present experimental study, the efficiency of permeable reactive barriers (PRBs) containing organic material mixed with zero-valent iron, fly ash or red mud to remove heavy metals from leachates was assessed. Upflow laboratory column experiments were carried out to assess system efficiency in terms of Cu, Zn, Ni and Mn removal. The initial concentration of each metal ion in the feed was 50 mg/L. X-ray diffraction as well as scanning electron microscopy and energy dispersive spectrometry were used to identify new mineral phases and to identify metal removal mechanisms. Results and analyses show that sorption and precipitation of metals as sulphides, hydroxides and other hydrated phases are the dominant metal removal mechanisms.

Keywords:

• Heavy metals
• Permeable reactive barriers
• Organic material

Acknowledgements

This study was carried out in the frame of Greece–Turkey bilateral cooperation project GSRT 10 TUR/1-38-1 “Treatment of Acid Mine Drainage Using Permeable Reactive Barriers (In-Situ Treatment) and Anaerobic Baffled Reactors (Ex-Situ Treatment)”.

Notes

Third International Conference on Environmental Management, Engineering, Planning and Economics (CEMEPE 2011) & SECOTOX Conference, 19–24 June 2011, Skiathos Island, Greece