Abstract:The complicated fibrousnetwork structure of lignocellulose has adverse impact on the starting time of biomass dry anaerobic digestion. According to the pyrolytic properties of lignin, thermochemical pretreatment by using fluidized bed was put forward to pretreat the biomass. The present work was aim to investigate the influences of the thermochemical pretreatment technique on the biogas production via biomass dry anaerobic digestion. Experiments for the biogas production via biomass dry anaerobic digestion using the corn stalk samples treated at 150℃, 170℃, 190℃, 210℃ in a fluidized bed and untreated sample were carried out at 35℃ for 42d, respectively. Obviously, the results showed that thermochemical pretreatment could change the fibrousnetwork structure of lignocellulose. It resulted 5.98%~22.25% and 1.75%~20.99% decrease on hemicellulose and lignin, and enhanced the methane production ranging in a certain temperature. The digestion time T80 mirrored the efficiency of fermentation, 190℃ and 210℃ pretreatments got the shortest digestion time which were shorter 3d than the untreated of 30d. The highest methane yield of 30d was obtained at 190℃ pretreatment biomass sample which was 16.30% higher and the startup time was 2.10d less than the untreated. Other pretreatments also improved the methane yield by 1.67%~9.78% and resulted the startup time less than the untreated. Although 210℃ pretreatment could destroy the structure of lignocellulose more seriously, it also led methane production reduction due to the more wastage of hemicellulose and cellulose. The conclusions could be made that thermochemical pretreatment technique is one of the effective methods to improve the methane production and accelerate the startup time of dry anaerobic digestion observably.