蒸汽爆破预处理玉米秸秆厌氧发酵实验研究

Study on Anaerobic Digestion of Steam-explosion Pretreated Cornstalk

2.0 Mpa压力下,保留时间60 s,90 s和120 s对玉米秸秆汽爆预处理后进行厌氧发酵生产沼气实验,研究汽爆预处理秸秆厌氧发酵规律,探讨提高秸秆厌氧发酵产气量的新工艺。结果表明:蒸汽爆破预处理后的秸秆比未经预处理秸秆中温厌氧发酵的产气量296.8 mL.g-1提高16.8%～63.2%,保压时间为120 s时,秸秆厌氧发酵沼气产量达到最大值428.5 mL.g-1干物质。汽爆处理玉米秸秆厌氧发酵沼气中CH4含量在60%以上,发酵第20d累积产气量达到总产气量的80%,未发生结壳现象,主发酵周期比未汽爆秸秆大大缩短。

To study the regularity of anaerobic digestion of steam-explosion pretreated cornstalk and find the new technics improving the biogas production of cornstalk, the cornstalk were pretreated by steam-explosion under the condition of pressure of 2.0 Mpa for 60 s, 90 s and 120 s. The results showed that at the temperature of 35℃, the steam-explosion treated cornstalk was digested more easily than the untreated cornstalk. The untreated cornstalk had a biogas production rate of 296.8 mL · g-1, and that for treated cornstalk increased by 16.8% - 63.2%. The largest biogas production rate of 428.5 mL · g-1 could be obtained for treated cornstalk with steam-explosion treating time of 120 s. The methane content in the biogas of pretreated cornstalk was above 60%, the biogas production could reach 80% of total yield within 20 days and no crusting was found in the whole fermentation process. And the fermentation for the pretreatcd cornstalk was significantly shorter than the untreated.