木质纤维素燃料乙醇蒸馏废水的高温厌氧处理及菌群结构分析

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

摘要:

【目的】为开发高效的高浓度木质纤维素燃料乙醇蒸馏废水厌氧处理及资源化利用工艺，以活性炭为载体，在实验室规模上对高温厌氧流化床反应器处理木质纤维素燃料乙醇蒸馏废水进行研究。【方法】反应器经65 d梯度驯化后启动，对工艺参数进行一系列优化，并通过基于16S rRNA基因的分子生态学技术分析厌氧污泥中的优势菌群。【结果】实验获得了最优的反应条件和处理效果：厌氧流化床反应器(Anaerobic fluidized bed reactor，AFBR)在温度55±1 °C、有机负荷率(OLR) 13.8 g COD/(L·d)及水力停留时间(HRT) 48 h操作时，COD去除率达到90%以上，同时甲烷产率达到290 mL/g COD；菌群鉴定分析结果显示高温厌氧活性污泥中Clostridia所占比例最大，产甲烷菌属以Methanoculleus和Methanosarcina为主，其它功能菌群主要为Alphaproteobacteria等。【结论】AFBR反应器可高效降解木质纤维素燃料乙醇蒸馏废水并产生生物能源甲烷，其反应体系内微生物种类丰富。

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.