不同品种甘蔗品种选择和工艺优化对乙醇产量的影响。
Impact of cultivar selection and process optimization on ethanol yield from different varieties of sugarcane.
机构信息
Department of Process Engineering, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa.
出版信息
Biotechnol Biofuels. 2014 Apr 12;7:60. doi: 10.1186/1754-6834-7-60. eCollection 2014.
BACKGROUND
The development of 'energycane' varieties of sugarcane is underway, targeting the use of both sugar juice and bagasse for ethanol production. The current study evaluated a selection of such 'energycane' cultivars for the combined ethanol yields from juice and bagasse, by optimization of dilute acid pretreatment optimization of bagasse for sugar yields.
METHOD
A central composite design under response surface methodology was used to investigate the effects of dilute acid pretreatment parameters followed by enzymatic hydrolysis on the combined sugar yield of bagasse samples. The pressed slurry generated from optimum pretreatment conditions (maximum combined sugar yield) was used as the substrate during batch and fed-batch simultaneous saccharification and fermentation (SSF) processes at different solid loadings and enzyme dosages, aiming to reach an ethanol concentration of at least 40 g/L.
RESULTS
Significant variations were observed in sugar yields (xylose, glucose and combined sugar yield) from pretreatment-hydrolysis of bagasse from different cultivars of sugarcane. Up to 33% difference in combined sugar yield between best performing varieties and industrial bagasse was observed at optimal pretreatment-hydrolysis conditions. Significant improvement in overall ethanol yield after SSF of the pretreated bagasse was also observed from the best performing varieties (84.5 to 85.6%) compared to industrial bagasse (74.5%). The ethanol concentration showed inverse correlation with lignin content and the ratio of xylose to arabinose, but it showed positive correlation with glucose yield from pretreatment-hydrolysis. The overall assessment of the cultivars showed greater improvement in the final ethanol concentration (26.9 to 33.9%) and combined ethanol yields per hectare (83 to 94%) for the best performing varieties with respect to industrial sugarcane.
CONCLUSIONS
These results suggest that the selection of sugarcane variety to optimize ethanol production from bagasse can be achieved without adversely affecting juice ethanol and cane yield, thus maintaining first generation ethanol production levels while maximizing second generation ethanol production.
背景
正在开发甘蔗的“能源甘蔗”品种，目标是利用甘蔗汁和蔗渣生产乙醇。本研究通过优化蔗渣的稀酸预处理条件以提高糖产量，对各种“能源甘蔗”品种的蔗汁和蔗渣的组合乙醇产率进行了评估。
方法
采用响应面法中的中心复合设计，研究了稀酸预处理参数对蔗渣样本组合糖产量的影响，然后进行酶解。在不同的固载量和酶用量下，利用最佳预处理条件（最大组合糖产量）产生的压榨浆作为基质，进行分批和分批同时糖化发酵（SSF）过程，旨在达到至少 40 g/L 的乙醇浓度。
结果
不同甘蔗品种的蔗渣预处理-水解的糖产量（木糖、葡萄糖和组合糖产量）存在显著差异。在最佳预处理-水解条件下，最佳品种与工业蔗渣的组合糖产量差异高达 33%。从表现最佳的品种（84.5%至 85.6%）经过预处理蔗渣的 SSF 后，整体乙醇产量也得到了显著提高，而工业蔗渣的乙醇产量仅为 74.5%。乙醇浓度与木质素含量和木糖与阿拉伯糖的比例呈负相关，但与预处理-水解的葡萄糖产量呈正相关。对品种的综合评估表明，与工业甘蔗相比，最佳品种的最终乙醇浓度（26.9%至 33.9%）和每公顷的组合乙醇产量（83%至 94%）都有了更大的提高。
结论
这些结果表明，在不影响果汁乙醇和甘蔗产量的情况下，可以选择甘蔗品种来优化从蔗渣生产乙醇，从而在保持第一代乙醇生产水平的同时，最大限度地提高第二代乙醇的生产。
Zotero 插件