甘蔗渣高温同步糖化发酵制取燃料乙醇研究

BIO-ETHANOL PRODUCTION BY HIGH TEMPERATURE SIMULTANEOUS SACCHARIFICATION AND FERMENTATION OF BAGASSE

研究添加不同量纤维素酶对甘蔗渣酶解效果的影响,结果表明葡萄糖浓度随加酶量增加而增加,最优的添加量为30FPU/(g原料)。利用克鲁维氏酵母(Kluyveromyces marxianus)NCYC 587,在42℃下进行甘蔗渣高温同步水解糖化发酵实验,发现额外添加β-葡萄糖苷酶能有效提高乙醇的质量浓度,经48h发酵,添加30IU/(g葡聚糖)的β-葡萄糖苷酶可提高乙醇浓度30%。通过分批补料方式提高固体浓度至20%,比较SSF和SHF两种工艺,发现前者经72h可产生36.2g/L乙醇,发酵效率为0.50g/(L·h),后者经120h可获得41.2g/L乙醇,发酵效率为0.34g/(L·h)。

The effects of adding cellulase on sugarcane bagasse hydrolysation and β-glucosidase on ethanol concentration were investigated. It was found that the concentration of concentration of cellulase, and 30FPU/g substrate was the optimum glucose was improved with increasing feeding feeding concentration. Thermotolerant yeast, Kluyveromyces marxianus NCYC 587, was used in the simultaneous saccharification and fermentation （SSF） of alkali pre-treated sugarcane bagasse. After 48 hours of fermentation at 42℃, 30% of ethanol was obtained with the adding amount of β-glucosidase of 30IU/g glucan, which meant that the additional adding of β-glucosidase would improve ethanol concentration efficiently. The content of dry matter was increased to 20% through fed-batch enzymatic hydrolysis, and two processes, simultaneous saccharification ＆ fermentation and separate hydrolysis and fermentation were compared. It was found that the ethanol concentration of SSF process could attain 36. 2g/L after 72 hours of fermentation and the ethanol productivity was 0. 50g/（ L·h）, and for comparison, the SHF process could attain 41.2g/L after 120 hours of fermentationm and the ethanol productivity was about O. 34g/（L·h）.