Influence of the preliminary storage on methane yield of anaerobic digestion of the organic fraction of municipal solid waste

Anaerobic digestion (AD) is a suitable management option for the energy valorization of many wastes, including the organic fraction of municipal solid waste (OFMSW). However, in some cases, long storage after the separate collection of this waste is required for management reasons, especially when the amount of waste to be treated temporarily exceeds the capacity of available AD plants. This study evaluates the biochemical methane potential (BMP) of the OFMSW after preliminary storage of 2, 6, and 10 days, in order to assess whether they are still suitable for AD or not. Moreover, the accuracy of three kinetic models (first order, Gompertz, and logistic models) in estimating the methane yield of stored OFMSW is tested. The resulting methane yield was between about 500 and 650 NmL·gVS−1 and slightly increased with the increase of the storage time after collection. Overall, this study has demonstrated that storage of OFMSW, when the collected amount of solid waste exceeds the treatment capacity of AD plants, a storage time up to 10 days does not impact the methane yield of the process.