利用酵母菌发酵水稻秸秆与甘薯生产燃料乙醇条件的响应面法优化
时间:2019-09-18 21:05 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：本课题采用响应面分析的方法,获得发酵生产乙醇的最佳条件。首先，通过Plackett-Burman（PB）Design筛选得到显著地影响乙醇产量的两个因子：pH，甘薯与水稻的含量的比值。然后，通过最陡爬坡设计试验以逼近最大乙醇产量区间：pH值是3，甘薯与水稻的含量的比值是2:1。最后通过Center-Composite Design (CCD)设计及其响应面分析确定酵母菌发酵水稻秸秆与甘薯生产燃料乙醇的重要参数的最佳条件是：pH值为5.5，甘薯与水稻的含量的比值为20:5.3，经过优化乙醇产量预测最大值是14.35%。39223 毕业论文关键词：酵母菌，燃料乙醇，响应面分析，水稻秸秆，甘薯 Optimization of Ethanol Fermentation Conditions by Yeast from Rice Stalks and Sweet Potato through Response Surface Methodology Abstract: In this research, the conditions of ethanol fermentation by yeast were optimized through response surface methodology. The Plackett-Burman (PB) design was adopted to find the significant factors which affected the ethanol yield, including the pH and the ratio of rice stalks to sweet potato. The steepest ascent experiment was conducted to approach the optimal area of ethanol producing conditions. The important parameters of optimal production conditions were reached by Central-composite design (CCD) and the results of response surface analysis as follows: the pH was 5.5, the ratio of rice stalks to sweet potato was 20:5.3, the medium containing 0.5% ammonium sulfate of the total, the fermentation time was 4 days, the ratio of soybean meal was 1%, the medium containing 5% glucose in total, the amount of yeast in total was 500OD, as the total amount was 50g, yeast was cultured at 30℃ for 2 days. At last, the predictive value of the ethanol production with optimization is 14.35%. Key words: ethanol; yeast; Response Surface Methodology; rice stalks; sweet potato 引言 1 1 材料与方法 1 1.1供试材料 1 1.1.1试剂及其配制 1 1.1.2菌株 2 1.1.3培养基 2 1.1.4仪器设备 2 1.2试验方法 2 1.2.1复苏菌种的方法 2 1.2.2配制培养基 2 1.2.3接入菌种 2 1.2.4酵母菌的扩培 3 1.2.5酵母菌OD值的测算 3 1.3实验设计 3 1.3.1 Plackett-Burman设计 3 1.3.2 最陡爬坡实验 4 1.3.3 Central-Composite 设计 4 2 结果与分析 4 2.1 Plackett-Burman（PB）设计的结果 4 2.2 最陡爬坡试验 6 2.3 中心复合设计（CCD）结果 6 结果 9 3.讨论 9 致谢： 9 参考文献： 9 引言 能源短缺问题一直是本世纪以来面临的重大难题之一，全球各国都在为如何开发新的环境友好型可再生生物能源而不懈努力，特别是作为汽油的替代品。之前一直消耗的是石油及煤炭这些不可再生能源的，然而据不完全估计，已经被探明的不可再生资源的储量是只能文持我们人类使用大约50年。开发可以重复使用的能源是人类现在所面对的难题之中最为严重的且紧急的了。研究发现，目前乙醇是最有希望成为未来的石油替代能源的生物能源之一，怎样去更为有效且合理地生产和利用这一潜在的资源，已成为世界上各个国家所关注的关键的领域之一。水稻秸秆和甘薯这些纤文质原料是利用酵母菌发酵法生产乙醇可利用的丰富原料。我国是农作物产量的大国，所以水稻秸秆和甘薯来源充沛，所以生产乙醇的成本会相应的降低。 (责任编辑：qin) |