| A lab-scale EGSB reactor fed by artificial brewery wastewater was operated under 20℃ continuously, and its process performance, characteristics of granular sludge, microbial community structure were investigated. The results indicated that:①after 184 days' operation, the organic loading rate of EGSB reactor could reach 10 kg/(m3·d) at HRT of about 18 h, the COD removal efficiencies were above 85%, and the specific biogas production was about 0.58 m3 per kilogram COD removed. ②As the organic loading rate increased, the average diameter of the granule increased, and the settling velocity increased too, but when the loading rate reached about 10 kg/(m3·d), the granular average diameter decreased slightly. Compared with the granular sludge operated at mesophilic condition, the ECP contents especially the protein contents in the granular sludge operated at 20℃ increased obviously. ③Compared with the seed sludge, the main Archaea (methanogenes) species in the sludge samples operated at different loading rates under 20℃ did not change greatly, but the dominant methanogenes in the sludge operated under 15℃ for 6 months seeded with the same mesophilic sludge changed obviously. |
