ANAEROBIC CO-DIGESTION OF ORGANIC WASTE: INFLUENCES PARTICLE SIZE AND CONCENTRATION TOTAL SOLIDS

摘要

In this investigation we studied the influence of particle size and concentration of total solids in the process of anaerobic co-digestion of vegetable solid waste with anaerobic sludge of sanitary sewage, in the proportion of 80 and 20% (weight percent) respectively. The experimental system consisted of nine batch anaerobic reactors with unit volume capacity of two liters. The particle sizes of the waste investigated were 1.68, 2.00, 3.36 mm and total solids concentration of 30.0, 40.0 and 50.5 gTS.L~(-1) with an experimental design consisting of three different treatments and three repetitions and 200-day monitoring period. The most representative efficiency of transformation of carbonaceous and nitrogenous material was observed in the treatment with substrate with particle size of 1.68 and concentration of total solids of 30.0 gTS.L~(-1) Therefore, it was evidenced that the biogas production rate was inversely proportional to the particle size and the concentration of total solids of the substrate when submitted to the anaerobic co-digestion process.