Characterization and Lab Tests aimed to the anaerobic digestion of food-processing industrial wastes

In the last decades AD has been extensively functional for energy recovery from biomasses, mainly the organic fraction of municipal solid wastes (OFMSW), manure and livestock wastes, crops and food wastes, besides its traditional application to the treatment of wastewater sludges. AD application to the valorization of organic wastes exceeds the obvious economic and environmental advantages, if compared to the use of raw combustible materials, and it is a milestone of current European regulations. This work is focused on the characterization of food-processing industrial wastes (from coffee and hazelnut processing) meant for the evaluation of their biogas and methane production. The gathered results allowed the estimation of theoretical biogas and methane production values which are in agreement with a technical and economic feasibility of the AD process. Some AD tests were then performed at a laboratory-scale in 6L reactors, considering a 3% w/w Total Solids content, mesophile environment (35°C) and operating in batch conditions. The experimental results were finally discussed and both tested mixtures appeared idoneous for the implementation of the anaerobic process on a larger scale.