Heavy Metals Removal from Sewage Sludge by Ornamental and Non-Ornamental Plants – Review

Abstract

Increase in sewage sludge production caused by increase in population density rises issue on its disposal in economic and environmental views. It is suggested that the sludge can be used for land application in agricultural field as fertilizers but there is presence of heavy metals in the sludge that may cause harmful effect on the environment and human health. Application of physical, chemical and biological treatment methods to reduce the sludge volume, pathogen and heavy metals content where mechanical equipment is utilized, are not economically friendly. Thus, a cheaper biological method; phytoremediation, is proposed where plants are being utilized to remove heavy metal content from the sludge before being used as fertilizers in agriculture. This review discusses about phytoremediation of sludge to remove heavy metals by using ornamental and non-ornamental plants.