摘要
以混合秸秆为唯一原料,混合接种瘤胃液与污泥,在半连续固态进料反应器中研究不同回流比和有机负荷组合对甲烷产率、发酵特性的影响。结果表明,在6个阶段中,当有机负荷(OLR)为4 g/(L·d),回流比为1∶1时,甲烷平均产率达到了768 m L/(L·d);单位秸秆TS产甲烷量为202 m L/g,具有明显成本优势。当OLR升高到6 g/(L·d)时,VFA积累明显,丙酸质量浓度高达6.54 g/L,并且出现丁酸的积累;该阶段氨氮质量浓度明显升高,达到了632.51 mg/L。固渣中纤维素和半纤维素在第2阶段降解程度最高,降解率达到了88.81%,而水解酶活和产甲烷效率的变化相关。通过三维荧光光谱分析,发现沼液中类酪氨酸产物、辅酶F420及腐殖酸类有机物的变化受回流比和有机负荷的影响,能直接反映产甲烷和发酵特性,而且腐殖酸类物质的积累是产甲烷作用受到抑制的重要原因。因此,合适的回流比和有机负荷对秸秆沼气工程长期稳定运行尤为关键。
After co-inoculation of rumen fluid with sludge, the methanogenic efficiency and anaerobic fermentation characteristics of straw which were influenced by combination of different digestate recirculation ratios and organic loading rates （OLR） at six stages, were studied in a semi-continuous reactor with solid-feeding device. The results showed that methane yield reached 768 mL/（ L. d） at 4 g/（L. d） of OLR and 1：1 of digestate recireulation ratio. Methane production was 202 mL/g （217 mL/g） at this stage, which had obvious cost advantage. However, VFAs were accumulated significantly with propionate concentration being as high as 6.54 g/L while ammonia nitrogen concentration reached 632.51 mg/L at 6 g/（L＇d） of OLR. Degradation degree of cellulose and hemicellulose in solid residues reached 88.81% at phase 2 whereas hydrolytic activities correlated with methanogenie efficiency. Through the analysis of three dimensional fluorescence spectrum, it was found that dissolved organic matters of tyrosine-like component, coenzyme F420 and humic acid were affected by digestate recirculation ratio and OLR. The changes of the components could directly reflect the methane-producing activities and fermentation characteristics. Moreover, accumulation of humic acid was responsible for decrease of methanogenic activity. Therefore, proper digestate recirculation ratio and OLR were indispensable to long-term stable operation of biogas engineering from straw by avoiding the accumulation of harmful components in liquid digestate.
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2016年第11期198-206,133,共10页
Transactions of the Chinese Society for Agricultural Machinery
基金
国家自然科学基金项目(21276114
21506076)
"十二五"国家科技支撑计划项目(2014BAC25B01)
关键词
秸秆
厌氧发酵
沼液回流比
有机负荷
发酵特性
straw
anaerobic fermentation
digestate recirculation ratio
organic loading rate
fermentation characteristics
作者简介
邓玉营（1978-），男，博士生，常州工程职业技术学院讲师，主要从事秸秆厌氧发酵研究，E-mail：8000000577@czie．edu．cn
通信作者：阮文权（1966-），男，教授，博士生导师，主要从事大型厌氧工程设计及运行研究，E-mail：wqruanjn@gmail．com
