Impact of Mechanical Stirring and Percolate Recirculation on the Performances of Dry Anaerobic Digestion

Dry anaerobic digestion (DAD) is an attractive method for simultaneous organic waste disposal and bioenergy recovery. DAD has the problems of low methane yields, reaction rates, easy inhibition due to its limited mass transfer heat transfer. In this work, two methods mechanical stirring percolate recirculation were compared regarding their capacities improving enhancing performances in batch experiments with sorghum stalks as a substrate. The cumulative biogas yield system stability investigated when linear velocity was 0 cm/s, 22 44 66 88 cm/s. When content highest. computational fluid dynamics (CFD) simulation indicated that shearing force near shaft largest. paddle at radial distance close center about −140 N/m2. ratio material stacking height reactor diameter (H/D) 3:2, AD showed best performance. A higher promoted contact between microorganisms substrate enhanced production. By combining stirring, increased by 28% static process because promotion DAD.