Mesophilic Fermentation of SOMW in a Micro Pilot-Scale Anaerobic Digester

One of the most promising processes to exploit Solid Olive-Mill Waste (SOMW) for energy production is anaerobic digestion. An experimental study has been carried out on SOMW and inoculum, consisting of Cattle Slurry Digested (CSD) and coming from an anaerobic digestion plant. A substrate with an optimal supply ratio equal to 2:1 has been investigated in a reactor at 37 C by analysing the biogas production. The Biochemical Methane Potential (BMP) test has been carried out, monitoring pH, biogas production (amount and composition). According to the tests results, SOMWs needed to be diluted and inoculated, moreover the pH control is foundamental in order to obtain a significant biogas production. Anaerobic digestion plant of SOMW should be promoted in Mediterranean countries as an environmentally sound option for waste management and energy production, since olive mills are very widespread ago-industries in this area.