Abstract: In order to investigate the effects of different total solids content（4%, 6%, 8%）and inoculation ratio （rI/S=1.5, 2.0, 3.0）on the mesophilic anaerobic digestion of swine manure, batch experiments were conducted using the Automatic Methane Potential Test System. Results showed that total solids content and inoculation ratio had a significant effect on daily and accumulated biogas production, and total solids content played a much more role than inoculation ratio. On the basis of the experimental parameters, the cumulative methane yield increases with the increase of the inoculation ratio, while with the increase of total solids content decreases after increasing first. The highest cumulative biogas yield and methane yield (469.1mL·g-1VS and 333.2mL·g-1VS) was achieved with total solids content of 6% and rI/S of 3.0. In addition, the kinetic model shows that the lower total solids content and the higher inoculation ratio increased the average daily methane production rate and shortened the lag phase of methanogenesis. The first-order kinetic model showed a better fit to the experimental results than the modified Gompertz model, and to a certain extent, the fit accuracy was improved with the increase in total solids content and inoculum rate.

Key words: Swine manure, Anaerobic digestion, Total solids content, Biochemical methane potential, Inoculation ratio, Kinetic