摘要
在两相联合厌氧发酵产氢气-甲烷系统中,采用上清液回流可以避免产氢相中的酸积累现象,但容易导致菌种混合,影响有机质降解。针对该问题,论文将回流液经过曝气处理,研究曝气时间和曝气方式对发酵系统产气及有机质降解特性的影响规律。试验发现,曝气可以有效抑制产氢相中产甲烷菌活性、提高气体产量,经过间歇曝气10 min的处理组,产氢相气体产量最高,比对照组提高29.7%,同时发酵液的VFA浓度峰值也最高,但曝气对产甲烷相气体产量有消极作用。曝气处理对产氢相及产甲烷相的挥发性脂肪酸浓度变化趋势无明显影响。间歇曝气、曝气时间分别为7 min和10 min的试验中发酵系统总COD降解率最高,分别达到82.1%,78.7%,比空白组分别提高了30.1%,26.7%,但连续曝气工艺在提高产气量和COD去除率方面不如间歇曝气效果显著。
In the two-phase anaerobic system producing hydrogen and methane,circulate the supernatant from the methane production phase （CH4-phase） to the hydrogen production phase （H2-phase） could prevent acid accumulation in H2-phase.But this method may cause the mixing of bacteria species in two phase and influence the normal digestion.To solve this problem,the reflux was aerobically treated before backflowing into H2-phase in this study.It was found that aerobic treatment of reflux could inhibit the methanogenic activity in hydrogenic phase and improve the hydrogen yield significantly.The highest hydrogen yield was increased by 29.7％ compared with the control when intermittent aeration was 10 min,and the volatile fatty acids （VFA） reached the peak concentration,while the aeration had a negative effect on the gas yield of CH4-phase.No obvious effect on VFA concentration in both phases.When the intermittent aeration was 7,10 min,respectively,the total COD degradation rate were 82.1％,78.7％,respectively,which was increased by 30.1％,26.7％ comparing with the control.The intermittent aeration had better effect than the continuous aeration on improving gas yield and COD removal.
出处
《中国沼气》
北大核心
2014年第1期61-64,12,共5页
China Biogas
基金
2013年度公益性行业(农业)科研专项(201303099)
湖北省高等学校青年教师深入企业计划(XD20100836)
关键词
两相联合发酵
氢气
甲烷
回流液
曝气处理
two-phase anaerobic fermentation
hydrogen
methane
reflux liquid
aeration treatment
