In this study, a novel process simulation model (PSM) was developed for anaerobic digestion using Aspen Plus® (version 7.3.2). PSM has two parts, one for hydrolysis working based on extent of reaction and the other on kinetics of reactions. A total of 53 reactions were used in the model including inhibitions, rate kinetics, pH, ammonia, volume and HRT. Each reaction set in the kinetic reactor has a FORTRAN program to calculate the kinetics of biogas production. PSM was validated with earlier research studies and industrial experiments in Aspen Plus®. The P-value after statistical analysis was found to be 0.324, which showed there was no significant difference between different validations, even after a change in process conditions, loading rate, HRT and substrate. The sensitivity analysis with a ±10% change in composition and extent of reaction would result in average 4.56% higher value than the experimental value.