Abstract

This study applied granular activated carbon (GAC) to improve the anaerobic digestion of long-chain fatty acid (LCFA). New kinetics were considered to describe the effect of GAC on the LCFA degradation, including i) The adsorption kinetics of GAC for LCFA, ii) The β-oxidation pathway of LCFA, iii) The attached biomass improved by direct interspecies electron transfer (DIET). The developed model simulated the anaerobic digestion of stearic acid, palmitic acid, myristic acid, and lauric acid with 1.00 and 2.00 g l−1 of GAC. The simulation results suggested that adding GAC led to the increase of km,CnGAC and km,acGAC. As the concentration of GAC increased, the values of kinetic parameters increased while the accumulated acetate concentration decreased. Thus, GAC improved the kinetic parameters of the attached syntrophic communities.