Biogas production from anaerobic co-digestion by using different inoculums

The treatment of organic solid waste (OW) is a huge problem because a lot of it is disposed of every year and needs to be treated. The anaerobic digestion of organic waste is considered one of the most promising processes. Based on the current research, the anaerobic digestion of (OW) is improved when the substrate is mixed with sewage sludge (SS) or cow manure (CM) during the digestion process. In addition to feedstock, operation parameters such as temperature, pH, and total solids have a significant impact on the rate and quality of biogas production. Experiments were done on the anaerobic digestion of the substrate for OW-SS and OW-CM using a digester with mesophilic conditions (temperature 37℃, and retention time 31 days). The pH value varied from (5.1 - 4.39) and (6.7 - 5.7) for OW-SS and OW-CM, respectively. The accumulation of methane production was recorded as (3409 ml) and (4914 ml), and the higher rate of methane concentration was estimated to be (52%) and (61%) for OW-SS and OW-CM, respectively. It can be concluded that the co-digestion of (OW-CM) gives more volume and quantity of methane generation than OW-SS.