Abstract:The improved particle swarm optimization (PSO) algorithm was used to estimate the key parameters of ADM1model. Through sensitivity analysis of key parameters, the Monod maximum uptake rate parameters km,i, half saturation constant Ks,i and the products yield from substrate fi were proved to be significant impact on the volatile fatty acids (VFAs) production. The revised kinetic parameters were integrated into the ADM1to modeling the VFAs production from anaerobic fermentation of sewage sludge by C/N regulation. The results indicated that the errors were low between the estimated and experimental determined VFAs production data, suggesting that the modified ADM1 model can be used to describe the effects of C/N regulation on the VFAs production from anaerobic digestion of sewage sludge well.