Addition of Different Biochars as Catalysts during the Mesophilic Anaerobic Digestion of Mixed Wastewater Sludge

Biochar (BC) recently gained attention as an additive for anaerobic digestion (AD). This work aims at a critical analysis of the effect six BCs, with different physical and chemical properties, on AD mixed wastewater sludge 37 °C, comparing their influence methane production kinetics. batch tests were performed laboratory scale operating 48 reactors (0.25 L working volume) 28 days addition 10 g L−1 BC. Most supplemented BCs exhibited higher (up to 22%) yields than control (0.15 Nm3 kgVS−1). The modified Gompertz model provided maximum rate values, in all lag-phase was equal zero days, indicating good adaptation inoculum substrate. potential correlations between BCs’ properties performance assessed using principal component (PCA). PCA results showed reasonable correlation O–C H–C molar ratios, volatile matter, biogas pore volume, specific surface area, fixed total carbon. In conclusion, physic-chemical BC (specifically, hydrophobicity morphology) key role improving sludge.