NaOH预处理对杂交狼尾草厌氧发酵产沼气的影响

Anaerobic fermentation of hybrid pennisetum for biogas under NaOH pretreatment

研究了Na OH预处理对杂交狼尾草厌氧消化制沼气的影响。采用质量分数分别为0%、2%、4%、6%和8%的Na OH溶液对杂交狼尾草进行碱预处理,在中温(35℃)、TS质量分数6%、接种率20%及初始p H为7.0条件下,进行厌氧发酵实验。对比了处理前后原料木质纤维素含量,探讨了不同浓度预处理对发酵过程沼气产量、甲烷浓度、p H以及产气速率的影响。结果表明,Na OH预处理有助于提高杂交狼尾草厌氧发酵的产气量和产气速率,其中4%Na OH预处理为较优条件。经4%Na OH溶液常温浸润24 h后,杂交狼尾草木质素降解率最大,比未处理实验组提高了31.2%;厌氧发酵总产气量比未处理实验组提高了31.6%。

In order to study the effect of alkali pretreatment on anaerobic fermentation of hybrid pennisetum( Pennisetum americanum × P. purpureum),Na OH solution with the concentrations of 0%,2%,4%,6% and 8%was used for material pretreatment,and the anaerobic fermentation was carried out at 35℃,with mass proportion of total solid( TS) being 6%,vaccination being 20% and the original p H being 7. 0. Combined with the measurement of the lignocellulose in hybrid pennisetum,the effect of Na OH pretreatment in different mass fractions on biogas yield,methane concentration,p H value and biogas producing rate was investigated during the fermentation process. The data showed that Na OH pretreatment can efficiently improve both of the biogas yield and biogas producing rate,with 4% being the optimum treating concentration which led to an increase of 31. 2% in lignin degradation degree and an increase of 31. 6% in biogas yield per unit mass of TS,as compared with control group.