两相厌氧发酵互花米草的特性

Anaerobic digestion of smooth cordgrass by two-phase process

利用两相(固态水解酸化相+湿式发酵产甲烷相)发酵互花米草,通过尿素的添加来调整厌氧发酵互花米草的碳氮比,考察两相厌氧发酵互花米草的特性;并利用FTIR考察水解发酵前后互花米草结构的变化.研究结果表明,由于固态水解渗滤液对尿素的淋滤,产生高浓度的氨氮溶液,抑制了湿式发酵产甲烷反应器中的甲烷菌;通过53 d的两相发酵互花米草,单位挥发性固体(VS)累积产气量仅为98.6 mL.g-1(0℃),转化率是理论产气量的17.5%;游离性氨(FA)浓度超过55 mg.L-1,就会严重抑制高温甲烷菌;红外光谱分析表明,石灰堆沤预处理对互花米草结构改变较小;只有大幅度的强化预处理,才能显著提高互花米草发酵的产气量.

Anaerobic digestion of smooth cordgrass by two-phase process was investigated with urea supplement for adjusting the ratio of carbon and nitrogen.The changes of lignocellulosic structure were investigated by FTIR analysis during lime compost and anaerobic hydrolysis.The results showed that methanogenic bacteria was exposed to FA（free ammonia） inhibition due to high ammonia content from leaching urea by leachate of solid-state hydrolysis,and the cumulative biogas yield added up to 98.6 mL·g-1VS（0 ℃） during 53 day two-phase digestion,only 17.5% of the theoretical value.When FA value was over 55 mg·L-1,methanogenic bacteria of thermophilic conditions suffered from serious inhibition.FTIR results showed that lime compost had a slight change in the lignocellulosic structure of smooth cordgrass.Pretreatment must be enhanced,to bring greater structural breakage for higher biogas production.