有机溶剂预处理对麦秆厌氧发酵产气的影响

目前,通过对秸秆进行化学预处理后产沼气的研究越来越多,其中以酸碱作为预处理试剂最为常见,但酸碱试剂对设备腐蚀较严重且对环境造成二次污染,故试验选择在厌氧发酵过程中可以被微生物分解的有机溶剂甲醇、丙酮进行预处理。为此,利用自行设计的可控性恒温发酵装置,以小麦秸秆为发酵原料,通过p H值、VFA、甲烷含量、还原糖等指标分析了秸秆经不同浓度的甲醇、丙酮处理后其厌氧发酵产气效率的变化。结果表明:浓度为3%、4%、5%的甲醇、丙酮预处理后的秸秆的累积产气量较对照组均有所提高。其中,5%丙酮处理秸秆后的发酵效果最好,较对照产气量增加了81%;经5%甲醇处理组的秸秆甲烷含量达到68%。

Effect of Organic Solvents Pretreatment on Biogas Production of Anaerobic Fermentation of Wheat Straw

Recently, studies on biogas generated by chemical pretreatment of straw are increasing, varieties of pretreat-ment reagents, including the most widly used acid and alkaline, have showed up.Those two, however, show heavy cor-rosion of equipment and cause secondary pollution to the whole environment.On the base of this, organic solvents which can be broken down by microorganisms in the anaerobic fermentation process, such as methanol and acetone, are selected in this study.With the raw material of wheat straw, anaerobic fermentation gas rate in different concentrations of methanol and acetone was analyzed through indicators such as pH, VFA, methane content and reducing sugar, by using an own-designed controllable thermostat fermentation equipment.The results indicated that straw cumulative gas production under pretreatments of methanol and acetone in the concentration of 3%, 4%and 5%were higher than the control group, the best was found in pretreatment of the 5% acetone which produced 81% gas more than control group did, and the methane content under 5% methanol reached 68% at the same time.Thus, the pretreatment of organic solvents has a significant promotion on anaerobic fermentation biogas.