Thermophilic anaerobic treatment of wastewater from lignocellulosic bioethanol distillation with microbial community analysis

Abstract:

[Objective] To develop efficient anaerobic treatment of wastewater from lignocellulosic bioethanol production, a laboratory-scale thermophilic anaerobic digestion in a fluidized bed reactor with activated carbon was developed. [Methods] After gradient domestication for 65 days, the operating parameters of the reactor have been optimized and dominant bacteria of the thermophilic anaerobic sludge were investigated based on 16S rRNA. [Results] The COD removal rate of 90% and methane yield of 290 mL/g COD were obtained at 55±1 °C, organic loading rate (OLR) of 13.8 g COD/(L?d) and hydraulic retention time (HRT) of 48 h in the anaerobic fluidized bed reactor (AFBR). The identification and analysis of bacteria showed that Clostridia accounts for the largest proportion of all microorganism and methanogen were dominated by Methanoculleus and Methanosarcina in thermophilic anaerobic sludge. [Conclusion] Bioethanol distilled wastewater can be degraded efficiently by abundant microbial species with methane production in AFBR.