[Performance and microbial community dynamic characteristics of an internal circulation reactor treating brewery...

A lab-scale internal circulation reactor (IC) fed by artificial brewery wastewater was operated with increasing volumetric loading rate under 35 degrees C continuously. The reactor performance and the relationship between microbial community structure and bioactivity in the anaerobic sludge were investigated during the operation. The COD removal efficiency was above 85%, furthermore, the maximum volumetric loading rate (VLR) and the maximum specific methanogenic activity (SMA) of the reactor could be up to 20 kg x (m3 x d)(-1) and 210 mL x (g x d)(-1) respectively. The results from the dehydrogenase and the bacteria DGGE experiments demonstrated that the dehydrogenase variation tendency was positively correlated to total light intensity of the whole bacteria DGGE bands for each sample. The total light intensity of the whole bacteria DGGE bands can use as a referential index for biomass liveweight in anaerobic system. Moreover, the coenzyme F420 content related to the relative abundance of Methanosaeta based on coenzyme F420 and archaebacteria DGGE analysis. As the volumetric loading rate increased, Methanomsaeta became significantly dominant, which was accompanied by the coenzyme F420 content increasing. The content could be up to 0.16 micromol x g(-1), meanwhile, the superiority of Methanosaeta became significantly obvious; UPGAMA analysis and Shannon index also confirmed the dynamic changes of microbial community structure during the operation.