生物质秸秆静态与动态厌氧消化产甲烷潜能对比研究

中温(32~35℃)环境下,通过对固含率为15%三种不同粒径的发酵物料(0.5 cm以下、1~2 cm、3~5 cm)的厌氧消化过程分析,并且对固含率20%、25%、30%与带消化液回流的厌氧发酵实验研究,结果表明:三种不同粒径发酵物料产气量最大的是<0.5 cm,其次依次为1~2 cm,3~5 cm,考虑到粒径小容易酸化的原因,选择秸秆厌氧消化的粒径范围0.5~2.0 cm;小麦秸秆无回流间歇发酵的产气率可达到每立方米发酵物料2~3 m3/d,带消化液回流的厌氧发酵产气率达到2.2 m3/(m3.d);初始固含率8%的发酵物料经过消化液回流、排剩,最终发酵物的固含率为16.4%;小麦秸秆无回流间歇发酵产甲烷潜能最大达249.0 m3/t,对应的固含率为25%,带消化液回流的厌氧发酵产甲烷潜能达223.06 m3/t。

COMPARISON OF METHANOGENESIS POTENTIAL WITH STATIC AND DYNAMIC ANAEROBIC DIGESTION OF BIOMASS STRAW STALK

In this paper,anaerobic digestion states of wheat straw stalk with different solid holdups under thermophilic temperature(32~35℃)were studied,and anaerobic digestion processes of a fermented matter with a solid holdup of 15% having different particle sizes(<0.5cm,1~2cm,3~5cm) were analyzed,and three different solid holdups(20%,25%,30%) and digest fluid backflow of anaerobic fermentation were studied by the experiment.The results showed that the highest gas production of the fermente matter with a solid holdup of 15% had the particle size of below 0.5 cm,followed by 1~2 cm and 3~5 cm.Based on the consideration of acidification,particle size of 0.5~2 cm was chosen for anaerobic digestion.Gas yield of the fermented matter/m3 could reach 2~3 m3/d with no reflow intermittent anaerobic fermentation,and gas yield of the one with digestive backflow of anaerobic fermentation of the fermented mattar was as 2.2 m3/d.After digested fluid backflow,the solid content rate hanged from 8% to 16.4%.Maximum methanogenesis potential of the fermeated matter with solid content rate of 25% was 249.0 m3/t with no reflow intermittent fermentation,and maximum methanogenesis potential of the one with digested fluid backflow of anaerobic fermentation was 223.06 m3/t.