Safe Reuse of Landfill Leachates for Irrigation Purposes

Abstract

The purpose of the present study was the assessment of the potential reusability of landfill leachates for agricultural irrigation, after advanced oxidation treatments. The UV/Fenton and Fenton processes were applied to the treatment of two different landfill leachate samples, L1 and L2, classified as intermediates, collected from two different landfills located in Macedonia, Greece. Samples were characterized by high COD and TOC values, ranging from 5500-6100 mg/l and 1700-1780 mg/l, respectively. The treatment efficacy and toxicity characteristics were evaluated by conducting phytotoxicity tests. Sorghum saccharatum seeds were used and the germination index (GI) was estimated. The results showed that the UV/Fenton process achieved better organic matter removal rates for both samples. The untreated undiluted leachates L1 and L2 were highly toxic, resulting in GI values of 0. The results of the study showed that Sorghum saccharatum seed germination depends on the nature of the irrigation media and that optimum germination rates were achieved at dilutions of treated leachates with ratios higher than 1:4.