秸秆分层多级转化液体燃料新工艺的研究进展

Studies on multi-level conversion of liquid fuel with straw

目前,秸秆主要作为性质单一组分的纤维素原料而采用生物转化法或快速热解法加以利用。生物转化法主要利用纤维素,而利用木质素和半纤维素较困难;快速热解生物质又使部分组分低值利用,而且得到的生物油品质低。为解决单一的生物或热转化方式存在的问题,提出秸秆分层多级转化液体燃料的新构思,即以秸秆“组分分离、分级定向转化”为核心,将生物转化和热转化有机结合多级转化生产燃料酒精与生物油。研究结果表明,秸秆经过汽爆处理后,采用高浓度发酵 分离乙醇耦合系统,可降低纤维素酶用量,提高了纤维素酶解效率,而且简化操作过程,使蒸馏前乙醇浓度达到6 0 %以上。发酵乙醇剩余物再经热解后,不但热解温度较原秸秆明显降低,而且所得生物油品质有了明显改观。

Straw characterized as the raw material of simplex cellulase is used mainly by biological conversion or fast pyrolysis.However,the former focuses on the cellulose utilization,with low wtilization rate of lignin and hemicellulose.In addition,biological oils obtained from fast pyrolysis are of low quality.A new notion of bio-liquid fuels production was advanced in the present paper to solve above problems e.g the bioful yielded through directional multi-level conversion.For steam-exploded straw,through coupling system of high-density fermentation and ethanol extraction,the cellulase loading can be decreased to a certain extent and the ethanol concentration yielded reaches 60%.Moreover,biological oil obtained through pyrolysis of fermented residue is of better quality than that directly yielded form straw.