Bio-Methane Production Potential Assays of Organic Waste by Anaerobic Digestion and Co-Digestion

The present study was conducted to investigate biochemical methane production potential (BMP) of the most abundant feed-stocks i.e., dairy manure (DM) and food wastes (FW) in agrarian countries by anaerobic digestion (AD) and co-digestion (Co-AD) under mesophilic (35 +/- 2 degrees C) settings at substrate to microorganism (S / M) ratio of 1.0 based on volatile solids (VS) for 30 days. Solids [Total solids (TS), volatile solids (VS), fixed solids (FS) and their ratios as (VS / TS)] determinations were also carried out for process monitoring. The highest cumulative biogas yield of 459.4 mL /g VS was observed in the co-digestion of DM + FW with 58.63 and 41.36 % CH4 and CO2 contents. BMP of the microcrystalline cellulose (MCC), FW and DM were observed as 401.2, 389.61 and 358.7 mL /g VS with CH4 and CO2 contents of 54.1 and 35.9, 51.13 and 42.2, 56.66 and 40 %, respectively. The volatile solids reductions were 82, 79, 59 and 71 % for MCC, FW, DM and FW + DM, respectively. These results indicate that FW and DM are very desirable substrates for AD and their Co-AD upturns the biogas generation efficiency. Thus, we can conclude that BMP assays are extremely useful to determine the amount of bio-methane and bio-degradability of the organic substrates and would facilitate in the preliminary selection systems for the field scale applications especially in framework of developing countries.