皇竹草厌氧发酵产沼气特性

STUDY ON THE FERMENTATION CHARACTERISTICS OF HERBA ANDROGRAPHITIS

在中温(35℃)条件下,采用批量厌氧发酵对生长期为35 d和68 d的皇竹草的发酵特性进行研究.实验结果表明,两组不同生产期的皇竹草C/N均较低,分别为14.75和17.52.经过45 d的厌氧发酵处理,生长期为35 d的皇竹草产气率为243.77ml.g-1VS,在第1天和第15天出现两个产气高峰,第45天的产气结束;生长期为68 d的皇竹草产气率为247.06 ml.g-1VS,出现4次产气高峰,第45天日产气量为512ml.生长期为35 d和68 d的皇竹草发酵液中乙酸、丙酸、丁酸含量分别为48.48%—72.71%、5.64%—22.99%、6.84%—26.71%和42.51%—64.17%、5.83%—34.20%、10.98%—34.41%,丙酸型发酵和丁酸型发酵交替进行.发酵液的pH值均先降低后升高最后保持相对稳定.皇竹草适合作为沼气发酵的原料加以利用.

The fermentation characteristics of 35 day and 68 day Herba Andrographitis were studied by batch anaerobic digestion at moderate temperature（35℃ ） . The results show that the C/N of the two different types of Herba Andrographitis are very low, 14.75 and 17.52 respectively. After 45 day treatment of anaerobic fermentation, the rate of gas production of the 35 day Herba Andrographitis is 243.77ml · g-1 VS. Two gas peaks appeared on the 1st and 15th day, and on the 45th day, gas production stopped. The rate of 68 day Herba Andrographitis is 247.06ml · g-1 VS, Four gas production peaks appeared . Gas production on the 45th day is 512ml. The Herba Andrographitis contained acetic acid, propionic acid and butyric acid, accounting for 48.48%--72.71% , 5.64%--22.99% , 6. 84%--26. 71% and 42.51%---64. 17% , 5.83%--34.20% , 10. 98% --34. 41% respectively. Acetic and butyric type fermentation took place alternately. The pH of the fermentation broth first dropped then increased finally maintained a relatively stable level. Herba Andrographitis can be used as a suitable raw material for methane fermentation.