高底物浓度纤维乙醇同步糖化发酵工艺的比较

引言日益加剧的能源危机和环境污染,正迫使人们寻求新的可再生替代能源。纤维乙醇作为一种重要的生物质替代能源,经过近40多年的发展,已经具备了实现工业化生产的潜力。为了进一步降低纤

Comparative study on processes of simultaneous saccharification and fermentation with high solid concentration for cellulosic ethanol production

The effects of various simultaneous saccharification fermentation(SSF) technologies on ethanol yield from cellulose were investigated.Using steam-exploded corn stalks as raw materials,five SSF technologies,including traditional SSF,SSF combined with preliminary enzymatic hydrolysis,fed-batch SSF coupled with preliminary enzymatic hydrolysis,SSF united with preliminary enzymatic hydrolysis coupling with vacuum separation and fed-batch SSF associated with preliminary enzymatic hydrolysis coupling with vacuum separation,were used for decomposition of the stalks.By comparing the fermentation process with higher solid concentration including 15%(mass) and 30%(mass),it was found that the fed-batch SSF combined with preliminary enzymatic hydrolysis is an effective way for raising substrate concentration.However,higher substrate concentration may lead to decrease of final ethanol yield.Moreover,SSF coupled with vacuum separation can weaken the product inhibition,and increase the ethanol yield.The ethanol productivity by the fed-batch SSF associated with preliminary enzymatic hydrolysis coupling with vacuum separation is 0.40 g·L-1·h-1,the highest value obtained,indicating that this technology can be a potential new technology.