Valorization of food waste leachates through anaerobic digestion

According to European Union data, on average 173 kg per person of total food waste (organic waste) are produced annually, of which 92 kg per person come from households (organic waste). Food waste is defined the waste from household, restaurants, canteens, food industries as well as markets. The importance of food waste stretches from environmental pressures to economic and social impacts. An Environmental technology for the biodegradation of food waste is Anaerobic digestion. Is a very attractive technique and combines waste treatment and renewable energy recovery. This study investigates the characteristics of food waste leachates from composting buckets and their valorization as substrate for anaerobic digestion process.
A complete characterization of different food waste leachates was conducted (pH, COD, VFAs, heavy metals etc.). Food waste leachates proved to be an ideal feedstock for Anaerobic digestion. In this direction, batch tests were performed to evaluate the methane yield of food waste leachates under different operating conditions. Three different SIR ratios were tested (0,5, 1,0 and 1,5) A SIR equal to 0.5 proved to be the as the higher methane yield was achieved. The removal of COD under all operating conditions was higher than 70% with the higher removal (85,18%) for an SIR equal to 1.5.