Anaerobic co-digestion of rabbit manure and sorghum crops in a bench-scale biodigester

ADROVER, MARÍA ESPERANZA; COTABARREN, IVANA; MADIES, EZEQUIEL; RAYES, MANUEL; RODRIGUEZ REARTES, SABRINA BELÉN; PEDERNERA, MARISA

Bioresources and Bioprocessing

SpringerOpen

Año: 2020 vol. 7

Any type of biomass can be used as substrate for biogas production, but theperformance of the biodigestion depends on the composition of the feed, and no directextrapolation of the yield of the process from one substrate to another can be made.In this work, the performance of a bench-scale anaerobic biodigester of 93 L installedat ambient conditions is studied. The biodigester was set up in a region wheretemperature varies significantly during the year, and was operated under semi-batchconditions with non-thermal control for 16 months with a feed of rabbit manure andground sorghum grains. To our knowledge, this is the first time the co-digestion ofrabbit manure with sorghum grains is considered. To evaluate the biodigestionperformance, critical operational variables (pH, temperature, biogas flowrate) weremonitored, and composition of substrate, digestate and produced biogas wasdetermined. Moreover, the following variables were quantified: a) the theoreticalmethane potential, b) the specific methane yield and c) the degree of degradation ofthe substrate. A 1-D non-stationary model was formulated and validated withexperimental data in order to analyze, in a theoretical form, the impact of incorporatingthermal insulation to the unit.